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Christian Weinand


chwscot@yahoo.com

Journal articles

2012
Truong Quang Vu Phan, Weiguo Xu, Gerald Spilker, Christian Weinand (2012)  Technique and indication of Distal Arterial-to-Proximal Venous Anastomosis at an Amputated Distal Phalanx   Hand Surgery 17: 1. 135 - 137 February  
Abstract: Digital finger amputation with soft tissue injury is a frequent accident in Reconstructive Surgery. Several techniques about reconstruction of digital finger amputation are described in literature. However replantation is difficult when large segments of the arteries are missing. This is especially true for distal finger phalanx amputations, where replantation is done in selected patients such as artists or musicians. In this article a microsurgical replantation techniques of a distal artery and proximal vein anastomosis is presented in a distal phalanx amputation, which successfully solved problem of venous reflux without venous anastomosis.
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Truong Quang Vu Phan, Panagiotis Theodorou, Christian Depner, Rolf Lefering, Walter Perbix, Gerald Spilker, Christian Weinand (2012)  Failure of secondary wound closure after sternal wound infection following failed initial operative treatment – Causes and treatment   Annals of Plastic Surgery 23:  
Abstract: Background: Patients transferred to Plastic Surgery Departments for sternum osteomyelitis have a high morbidity of about 3%. Despite several known options for sternal wound coverage and salvage operations, wound dehiscence or wound necrosis can occur, increasing patient morbidity. Patients and Methods: 135 patients admitted from January 2007 to December 2010 were evaluated in a retrospective study for wound dehiscence after salvage wound coverage at our institution. Various flaps were applied such as pectoralis major myocutaneous pedicled flaps, pectoralis major muscle pedicled flaps, latissimus dorsi pedicled flaps, greater omental flaps, VRAM and TRAM flaps. Inclusion criteria were sternal wound infection, bacterial wound infection, previous wound debridement outside our institution, vacuum assisted closure device wound treatment at our institution, and secondary flap closure of the sternal defect at our institution. A multivariate regression analysis was performed. Results: 130 patients met the inclusion criteria. In all patients, bacterial wound colonization was shown. 40 patients showed wound dehiscence after closure at our institution. Reasons for wound dehiscence were attributed to wound size, more than four different species of bacteria colonizing the wound, gram negative bacteria, candida albicans, ICU stay, and female gender. Interestingly wound dehiscence was not significant correlated to obesity, smoking, atherosclerosis, renal insufficiency or type of closure influenced significantly or necrosis. Conclusion: Female patients after CABG with large sternal wounds infected with gram negative bacteria and candida have an 85% risk of wound dehiscence after flap coverage for sternal wound infection.
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Stefan Ehrendorfer, Anil Sethi, Bilal Jamal, Leith Albadran, Christian Weinand, Herwig Drobetz (2012)  Mini invasive open Surgery Bankart repair for recurrent traumatic shoulder instability a single surgeon/ single institution's experience   European Orthopaedics and Traumatology  
Abstract: Background Primary traumatic anterior dislocations of the shoulder are common injuries which are complicated by persistent instability in a high proportion of patients. Surgery is successful and has been well described in the literature. Current scientific debate centres on the role of open and arthroscopic techniques. We describe the outcomes of a mini-invasive open surgery modified Bankart technique which was developed within our institution. Methods Twenty-six patients with traumatic shoulder instability (one bilateral) were prospectively entered into a database between June 1998 and March 2008. The mean age was 28 years, and the mean follow-up period was 58 months. Twenty-seven shoulders underwent shoulder arthroscopy and mini-invasive open surgery using a delto-pectoral approach with subscapularis muscle split and three bio-absorbable anchor-fixations of the avulsed Bankart–labrum–capsule complex. Results Patients reported no re-dislocation in 24 shoulders (89 %). Three shoulders re-dislocated with additional trauma. Satisfaction was very good in 16 and good in nine shoulders (93 %). Nineteen patients had minimal or no pain. Seven patients experienced moderate shoulder pain, and none complained of severe pain. VAS and QuickDASH (Disability Arm Shoulder Hand) scores were encouraging. Conclusions Our technique combines the ability to appreciate all shoulder pathology arthroscopically with the visualisation and operative tissue handling gained in open Bankart surgery. This technique facilitates to judge the need for anterior capsular shift and perform it in an open procedure without detachment of subscapularis muscle. Functionally, patients do well. The low re-dislocation rate, only reported after significant additional trauma, is encouraging. We feel that long-term outcomes are needed using larger cohorts of patients to identify if this technique will fulfil its promise.
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2011
Christian Weinand, Afshin Nabili, Mohammed Khumar, Joey R Dunn, Jessica Ramella-Roman, James C Jeng, Marion H Jordan, Yasuhiko Tabata (2011)  Factors of Osteogenesis influencing various human stem cells on third generation gelatin/β-TCP scaffold material   Rejuvenation Research 14: 2. 185-194 April  
Abstract: Human bone marrow derived stem cells (hBMSCs) and adipose derived stem cells (hASCs) have been used to regenerate bone. Both sources are claimed to have comparable osteogenic potential but few comparative studies are available. Third generation biomaterials have been developed to reduce steps in regenerating tissues. For osteogenesis gelatin/β-Tricalcium phosphate (β-TCP) scaffolds with incorporated controlled release BMP2 as third generation biomaterials were recently developed. So far, few studies on protein induced osteogenesis versus chemical induced osteogenesis have been performed. This study evaluates osteogenic potential of hBMSCs derived versus hASCs on gelatin/β-TCP scaffolds in vitro under four different conditions. Gelatin/β-TCP scaffolds with and without incorporated controlled release BMP2were seeded with hBMSCs or hASCs under oscillating fluid conditions in osteogenic (OS) or growth media (GM). All were evaluated radiologically (CT scan), histologically, biomechanically and for gene expression at 1, 2, 4 and 6 weeks. Highest radiological densities were seen in specimens at six weeks with controlled release BMP2, close to native bone. HBMSCs, hASCs, OS, GM conditions resulted in similar bone formation with gelatin/ β-TCP scaffolds and incorporated controlled release BMP2. This was confirmed histologically by Toluidine blue and van Kossa staining and biomechanically. Gene expression studies of these specimens showed presence of pre-osteoblasts, transitory osteoblasts and secretory osteoblasts. Specimens comprised of gelatin/β-TCP scaffolds without incorporated controlled release BMP2 in OS showed lesser bone formation. HASCs and hBMSCs have similar osteogenic potential. HASCs are an attractive alternative to hBMSCs for bone regeneration using third generation gelatin/β-TCP scaffolds with incorporated controlled release BMP2.
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Borut Banic, Andrej Banic, Esther Vögelin, Harald M Bonel, Christian Weinand (2011)  Large ulcerating metastasizing basal cell carcinoma of the back   Zdravniski Vestnik 80: 137 - 141  
Abstract: So far, computed tomography (CT) and magnetic resonance imaging (MRI) have been employed for the search of metastasis of basal cell carcinomas (BCC). We have used PET-CT to detect metastases of BCC not yet visible with other techniques. BCC of the trunk are reportedly larger than those located at the head and neck region. These tumors have also a higher incidence to metastasize. Although it has been proposed in literature the TNM (Tumor-Nodes-Metastases) system is not being used routinely for metastasizing BCC. There have been 19 reports of metastasizing BCC of the trunk. We present a case of a 78- year old male patient with large ulcerating metastasizing BCC of the trunk. Literature is reviewed for similar cases and the TNM system is applied.
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Borut Banic, Bernhard Meier, Andrej Banic, Christian Weinand (2011)  Thoracic Radionecrosis Following Repeated Cardiac Catheterization   Radiology Research and Practice 2011:  
Abstract: Radiodermatitis is a known complication in patients having undergone radiotherapy. It usually appears 2 to 5 years after irradiation. We are reporting on a case of radiodermatitis that occurred within months after coronary dilatation and stenting. It started with painful swelling, followed by a typical appearance on the skin surface. Histological finding confirmed the diagnosis. However, magnetic resonance imaging showed changes in the subcutaneous tissue extending into the ribs. A radical debridement was performed including removal of a partially necrotic 4th rib. The defect was closed with a latissimus dorsi transposition flap. Our findings are compared with the literature reports.
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Panagiotis Theodorou, Truong Quang Vu Phan, Christian Weinand, Marc Maegele, Christoph Andreas Maurer, Walter Perbix, Sebastian Leitsch, Rolf Lefering, Gerald Spilker (2011)  Suicide by burning Epidemiological and Clinical Profile   Annals of Plastic Surgery 66: 4. 339-43 April  
Abstract: Self-immolation demonstrates a rare form of suicide in developed countries, though it accounts for unique injury characteristics in the burn intensive care unit. The aim of this study was to present the epidemiological and clinical features of patients burned during a suicidal attempt seen in North Rhine-Westfalia BICU. To address this aim, we undertook a 21-year retrospective study involving patients with termal injuries admitted to the largest burn unit in Germany. A total of 125 suicide-related burn victims were identified in the study period (9.4%). Comparing the self-immolation group with the rest of the burn patient cohort, suicide victims were more likely to be single and to act under the influence of alcohol. The suicidal group had a larger extent of burns, higher incidence of inhalation injury, required more surgical procedures, catecholamines, blood transfusions, and a longer BICU stay. Their clinical course was complicated by prolonged intubation period, higher rate of multiple drug-resistant bacteria aquisitions and sepsis, leading to a higher mortality rate. Although the proportion of self-immolation victims among all burned patients is not high, the markedly higher severity of their burns and their poorer quality of outcomes makes them an important clinical subgroup for further study.
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Truong Q V Phan, Gerald Spilker, Panagiotis Theodorou, Andreas Gossmann, Michael Heiss, Christian Weinand (2011)  Combined latissimus dorsi and serratus anterior flaps for pelvic reconstruction   Microsurgery 31: 7. 529 - 534 October  
Abstract: In recurrent pressure sores, adjacent tissue has already been consumed by multiple surgeries. Additional problems are several co-morbidities of patients. Especially, severe atherosclerosis would be a contraindication for using free flaps. However, microsurgical techniques allow circumventing these limitations and preparing even severely atherosclerotic vessels. We performed a total of 8 sacral pressure sore coverage in our standardized fashion, using the free combined latissimus dorsi and serratus anterior free flap. All patients had severe atherosclerosis and needed large soft tissue coverage of the sacral defects. Five patients presented after bowel resection, 3 with recurrent sacral pressure sores. The average follow up was 12 months. Postoperatively, all patients were allowed to be prone on the operated area. One minor wound dehiscence was sutured in local anesthesia. CT imaging analysis of the pelvis showed complete void space coverage. The combined latissimus dorsi and serratus anterior flap is a valuable tool for pelvic reconstruction in our hands. In addition, severe atherosclerosis should not be considered an obstacle to microsurgery and the use of free flaps.
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Christian Weinand, Cameron Akbari, Sean O'Donnell (2011)  A High Bifurcation of the Dorsal Branch with Dominant Superficial Palmar Branch of the Radial Artery: A Case Report of an Aberrant Radial Artery with Traumatic Aneurysm   Journal of Hand and Microsurgery 3: 2. 78 - 81 October  
Abstract: Anatomical abnormalities such as unusual bifurcations or aberrant arteries of the radial artery are extremely rare and due to malformation or disruption of the vascular net. We present a case of a 64 year old woman with a high bifurcated dorsal branch of the left radial artery, consulting us for a pulsatile mass in the anatomical snuffbox after a fall. The mass measured 3–4 mm in diameter and was located on the dorsal aspect of the wrist over the anatomical snuffbox. Primary imaging studies using Duplex Ultrasound suggested an aneurysm of the radial artery, further imaging with arteriogram revealed a high bifurcation of the dorsal branch of the radial artery, presenting with an aneurysm. The deep palmar branch of the ulnar artery was the dominating vessel, allowing ligation and excision of the aneurysm. Histological evaluation revealed intimal wall hyperplasia within the aneurysm, suggesting an injury as initiating factor. A review of the literature showed that this abnormality of high bifurcation of the dorsal palmar branch of the radial artery has not been previously reported. Management of aneurysms at the wrist is discussed.
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2010
Lan B Van-Buendia, Rebekah R Allely, Ronald Lassiter, Christian Weinand, Marion H Jordan, James C Jeng (2010)  What's Behind the Mask? A Look at Blood Flow Changes With Prolonged Facial Pressure and Expression Using Laser Doppler Imaging   Journal of Burn Care & Research 31: 441-7 May-Jun  
Abstract: Clinically, the initial blanching in burn scar seen on transparent plastic face mask application seems to diminish with time and movement requiring mask alteration. To date, studies quantifying perfusion with prolonged mask use do not exist. This study used a laser Doppler imaging (LDI) to assess perfusion through the transparent face mask and movement in burned and unburned subjects over time. Five subjects fitted with transparent face masks were scanned with the LDI on four occasions. The four unburned subjects were scanned in the following manner: 1) no mask, 2) mask on while at rest, 3) mask on with alternating intervals of sustained facial expression and rest, and 4) after mask removal. Images were acquired every 3 minutes throughout the 85-minute study period. The burned subject underwent a shortened scanning protocol to increase comfort. Each face was divided into five regions of interest for analysis. Compared with baseline, mask application decreased perfusion significantly in all subjects (P < .0001). Perfusion did not change during the rest period. There were no significant differences with changing facial expression in any of the regions of interest. On mask removal, all regions of the face demonstrated a hyperemic effect with the chin (P = .05) and each cheek (P < .0001) reaching statistical significance. Perfusion levels did not return to baseline in the chin and cheeks after 30 minutes of mask removal. Perfusions remain constantly low while wearing the face mask, despite changing facial expressions. Changing facial expressions with the mask on did not alter perfusion. Hyperemic response occurs on removal of the mask. This study exposed methodology and statistical issues worth considering when conducting future research with the face, pressure therapy, and with LDI technology.
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2009
Rose D Baker, Christian Weinand, James C Jeng, Henk Hoeksema, Stan Monstrey, Sarah A Pape, Robert Spence, David Wilson (2009)  Using ordinal logistic regression to evaluate the performance of laser-Doppler predictions of burn-healing time.   BMC Med Res Methodol 9: 1. Feb  
Abstract: ABSTRACT: BACKGROUND: Laser-Doppler imaging (LDI) of cutaneous blood flow is beginning to be used by burn surgeons to predict the healing time of burn wounds; predicted healing time is used to determine wound treatment as either dressings or surgery. In this paper, we do a statistical analysis of the performance of the technique, using data from a study carried out by five burn centers: LDI once between days 2 to 5 post burn, and healing assessed at 14 days and 21 days post burn. Random-effects ordinal logistic regression and other models such as the continuation ratio model were used. RESULTS: Overall performance is that diagnoses are over 90% correct. Related questions addressed were what was the best blood flow summary statistic and whether, given the blood flow measurements, demographic and observational variables had any additional predictive power (age, sex, race, % total body surface area burned (%TBSA), site and cause of burn, day of LDI scan, burn center). It was found that mean laser-Doppler flux over a wound area was the best statistic, and that, given the same mean flux, women recover slightly more slowly than men. Further, the likely degradation in predictive performance on moving to a patient group with larger %TBSA than those in the data sample was studied, and shown to be small. Statistical methods were also used to study the false-color palette, which enables the laser-Doppler imager to be used by clinicians as a decision-support tool. Here the conclusion is that an optimum three-color palette can be chosen 'automatically', but the optimum choice of a 5-color palette cannot be made solely by optimizing the percentage of correct diagnoses. CONCLUSIONS: Modeling healing time is a complex statistical problem, with random effects due to multiple burn areas per individual, and censoring caused by patients missing hospital visits. This analysis applies state-of-the art statistical methods such as the bootstrap and permutation tests to a medical problem of topical interest. New medical findings are that age and %TBSA are not important predictors whereas gender does influence recovery time, even when blood flow is controlled for.
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Christian Weinand, Jian-Wei Xu, Giuseppe M Peretti, Lawrence Bonassar, Thomas J Gill (2009)  Conditions affecting cell seeding onto three-dimensional scaffolds for cellular-based biodegradable implants.   J Biomed Mater Res B Appl Biomater 91: 1. 80-7 Oct  
Abstract: Seeding cells efficiently and uniformly onto three-dimensional scaffolds is a key element for engineering tissues, particularly when only a low-number of cells is available for tissue repair and regeneration. The aim of this study was to evaluate three seeding techniques on two biocompatible scaffolds in vitro using chondrocytes as follows: (1) static; (2) modified centrifugal cell immobilization (CCI); and (3) dynamic oscillating motion. Five milliliters of media containing 5, 10, or 25 million articular, auricular, or costal chondrocytes were used to seed porous PLGA scaffolds and sections of devitalized cartilage. The dynamic oscillating technique resulted in up to 150% higher cellular load at 7 days than CCI seeding. Cell distribution was more homogeneous throughout the scaffold under dynamic conditions versus more sporadic and dispersed cell concentrations on the scaffolds when using either the static or the modified CCI technique. Cell load and distribution, when using a low numbers of chondrocytes at one and two million cells per milliliter, was comparable to that using the much higher number, especially under dynamic seeding conditions. The seeded scaffolds were used as implants to achieve cellular bonding between two devitalized meniscus discs. The constructs were implanted subcutaneously in nude mice for 12 weeks and analyzed histologically. Implants seeded with auricular chondrocytes showed qualitative more integration into native meniscus tissue than articular and costal cell implants. We conclude the dynamic oscillating seeding technique is an efficient technique for seeding low-cell numbers onto scaffolds resulting in consistent and uniform cell distribution throughout porous PLGA scaffolds. (c) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009.
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Christian Weinand (2009)  The Vacuum-Assisted Closure (VAC) Device for Hastened Attachment of a Superficial Inferior-Epigastric Flap to Third-Degree Burns on Hand and Fingers.   J Burn Care Res 30: 2. 362-365 Mar/Apr  
Abstract: The vacuum-assisted closure (VAC) device has a wide range of clinical applications, including treatment of infected surgical wounds, traumatic wounds, pressure ulcers, wounds with exposed bone and hardware, diabetic foot ulcers, and venous stasis ulcers. Increased release of growth factors has been described, leading to improved vascularization and thereby formation of new tissue. The system is also used in burn surgery for reconstructive purposes. In this case report, a patient suffered from a third-degree burn injury to the dorsum of the hand with exposure of tendons, necessitating the use of a flap reconstruction. The patient was treated with a superficial inferior-epigastric artery-based flap and the VAC system was applied in a created glove-like shape. Hastened attachment of the flap onto the exposed fingers was observed after 4 days. The author reports on the additional use of the VAC system to hasten flap attachment in a patient with a burn injury to the dorsum of the hand.
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Christian Weinand, Rajiv Gupta, Eli Weinberg, Ijad Madisch, Craig M Neville, Jesse B Jupiter, Joseph P Vacanti (2009)  Toward regenerating a human thumb in situ.   Tissue Eng Part A 15: 9. 2605-15 Sept  
Abstract: Regenerative technology promises to alleviate the problem of limited donor supply for bone or organ transplants. Most expensive and time consuming is cell expansion in laboratories. We propose a method of magnetically enriched osteoprogenitor stem cells, dispersed in self-assembling hydrogels and applied onto new ultra-high resolution, jet-based 3D printing of living human bone in a single-step for in-situ bone regeneration. Human mesenchymal stem-cells (hBMSCs) were enriched with CD 117+ osteoprogenitor cells, dispersed in different collagen I, RAD 16I hydrogels mixes and applied onto 3-dimensional printed (3DP) beta-TCP/PLGA scaffolds, printed from ultra-high-resolution volumetric CT (VCT) images of a human thumb. Constructs were directly implanted subcutaneously into nude mice for 6 weeks. In-vivo radiographic VCT scanning and histological evaluations were performed at 1, 2, 4 and 6 weeks, expression of bone-specific genes and biomechanical compression-testing at 6 weeks endpoint. Time dependant accumulation of bone-like extracellular matrix was most evident in CD 117+ hBMSCs using collagen I/RAD 16I hydrogel mix. This was shown histologically by Toluidine blue, von Kossa and alkaline-phosphatase staining, paralleled by increased radiological densities within implants approximating that of human bone, and confirmed by high expression of bone-specific osteonectin and biomechanical stiffness at 6 weeks. Human origin of newly formed tissue was established by expression of human GAPDH using RT-PCR. Statistical analysis confirmed high correlations between biomechanical stiffness, radiological densities and bone-markers. Bone tissue can be successfully regenerated in-situ using a single-step procedure with constructs comprised of RAD 16I /collagen I hydrogel, CD 117+ enriched hBMSCs and porous beta-TCP/PLGA scaffolds.
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Christian Weinand, Ananth Murthy (2009)  Liquid silicone breast cosmesis—pros and cons of a conversely discussed material in a case report of silicone pneumonia in a transsexual male   European Journal of Plastic Surgery 32: 4. 209-12 Aug  
Abstract: Despite safe use of medical purity grade silicone, several reports on complications exist in literature. The Food and Drug Administration has issued warnings about health risks involving adultered or impure silicone in the 1960s. However, this potentially lethal practice by not-medical professionals is still widely spread. Most complications concerning liquid silicone injection in breast tissue are in the transgender patient population. Most individuals were seeking low cost– maximum result treatment. Resulting silicone pneumonia is only one possible life-threatening complication that, when diagnosed too late, can lead to death. Early treatment using systemic steroids and antibiotics is mandatory. We are presenting the case of an 18-year-old male to female transgender, presenting with silicone pneumonia after injection of liquid silicone into the breast tissue. The pros and cons of silicone and a short outline of the history of silicone are presented; diagnostic tools and treatment options are illuminated.
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2008
2007
Christian Weinand, Rajiv Gupta, Eli Weinberg, Ijad Madisch, Jesse B Jupiter, Joseph P Vacanti (2007)  Human shaped thumb bone tissue engineered by hydrogel-beta-tricalciumphosphate/poly-epsilon-caprolactone scaffolds and magnetically sorted stem cells.   Ann Plast Surg 59: 1. 46-52; discussion 52 Jul  
Abstract: Traumatic amputation of a thumb with bone loss leaves a patient in severe disability. Reconstructive procedures are restricted by limited shape and have the disadvantage of severe donor-site morbidity. To overcome these limitations, we used a tissue engineering approach to create a distal thumb bone phalanx, combining magnetically sorted 133+ human mesenchymal stem cells (hMSCs) suspended in successful tested hydrogels for bone formation and porous 3-dimensionally printed scaffolds (3DP) in the shape of a distal thumb bone phalanx. Collagen I and fibrin glue hydrogels with suspended hMSCs were first histologically evaluated in vitro for bone formation after 6 weeks.Then 3DP scaffolds, made from a mix of osteoinductive and -conductive beta-tricalciumphosphate (beta-TCP) and poly-epsilon-caprolactone (PCL), with hydrogels and suspended hMSCs, were implanted into nude mice subcutaneously for 15 weeks. Histologic evaluation, high-resolution volumetric CT (VCT) scanning, and biomechanical testing confirmed formation of bonelike tissue. Both hydrogels with CD 133+ hMSCs on 3DP scaffolds supported bone formation. Collagen I resulted in radiologically better bone formation. Bone tissue can be successfully tissue engineered with CD 133+ hMSCs, collagen I hydrogels, and porous 3DP beta-TCP/PCL scaffolds.
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Christian Weinand, Rajiv Gupta, Albert Y Huang, Eli Weinberg, Ijad Madisch, Rameez A Qudsi, Craig M Neville, Irina Pomerantseva, Joseph P Vacanti (2007)  Comparison of hydrogels in the in vivo formation of tissue-engineered bone using mesenchymal stem cells and beta-tricalcium phosphate.   Tissue Eng 13: 4. 757-765 Apr  
Abstract: Availability of grafts and morbidity at the donor site limit autologous transplantation in patients requiring bone reconstruction. A tissue-engineering approach can overcome these limitations by producing bone-like tissue of custom shape and size from isolated cells. Several hydrogels facilitate osteogenesis on porous scaffolds; however, the relative suitability of various hydrogels has not been rigorously assessed. Fibrin glue, alginate, and collagen I hydrogels were mixed with swine bone marrow-derived differentiated mesenchymal stem cells (MSCs), applied to 3-dimensionally printed porous beta-tricalcium phosphate (beta-TCP) scaffolds and implanted subcutaneously in nude mice. Although noninvasive assessment of osteogenesis in 3 dimensions is desirable for monitoring new bone formation in vivo, correlations with traditional histological and mechanical testing need to be established. High-resolution volumetric computed tomography (VCT) scanning, histological examination, biomechanical compression testing, and osteonectin (ON) expression were performed on excised scaffolds after 1, 2, 4, and 6 weeks of subcutaneous implantation in mice. Statistical correlation analyses were performed between radiological density, stiffness, and ON expression. Use of collagen I as a hydrogel carrier produced superior bone formation at 6 weeks, as demonstrated using VCT scanning with densities similar to native bone and the highest compression values. Continued contribution of the seeded MSCs was demonstrated using swine-specific messenger ribonucleic acid probes. Radiological density values correlated closely with the results of histological and biomechanical testing and ON expression. High-resolution VCT is a promising method for monitoring osteogenesis.
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2006
Christian Weinand, Irina Pomerantseva, Craig M Neville, Rajiv Gupta, Eli Weinberg, Ijad Madisch, Frederic Shapiro, Harutsugi Abukawa, Maria J Troulis, Joseph P Vacanti (2006)  Hydrogel-beta-TCP scaffolds and stem cells for tissue engineering bone.   Bone 38: 4. 555-563 Apr  
Abstract: Trabecular bone is a material of choice for reconstruction after trauma and tumor resection and for correction of congenital defects. Autologous bone grafts are available in limited shapes and sizes; significant donor site morbidity is another major disadvantage to this approach. To overcome these limitations, we used a tissue engineering approach to create bone replacements in vitro, combining bone-marrow-derived differentiated mesenchymal stem cells (MSCs) suspended in hydrogels and 3-dimensionally printed (3DP) porous scaffolds made of beta-tricalcium-phosphate (beta-TCP). The scaffolds provided support for the formation of bone tissue in collagen I, fibrin, alginate, and pluronic F127 hydrogels during culturing in oscillating and rotating dynamic conditions. Histological evaluation including toluidine blue, alkaline phosphatase, and von Kossa staining was done at 1, 2, 4, and 6 weeks. Radiographic evaluation and high-resolution volumetric CT (VCT) scanning, expression of bone-specific genes and biomechanical compression testing were performed at 6 weeks. Both culture conditions resulted in similar bone tissue formation. Histologically collagen I and fibrin hydrogels specimens had superior bone tissue, although radiopacities were detected only in collagen I samples. VCT scan revealed density values in all but the Pluronic F127 samples, with Houndsfield unit values comparable to native bone in collagen I and fibrin glue samples. Expression of bone-specific genes was significantly higher in the collagen I samples. Pluronic F127 hydrogel did not support formation of bone tissue. All samples cultured in dynamic oscillating conditions had slightly higher mechanical strength than under rotating conditions. Bone tissue can be successfully formed in vitro using constructs comprised of collagen I hydrogel, MSCs, and porous beta-TCP scaffolds.
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Christian Weinand, Giuseppe M Peretti, Samuel B Adams, Mark A Randolph, Estafios Savvidis, Thomas J Gill (2006)  Healing potential of transplanted allogeneic chondrocytes of three different sources in lesions of the avascular zone of the meniscus: a pilot study.   Arch Orthop Trauma Surg 126: 9. 599-605 Nov  
Abstract: Successful treatment of tears to the avascular region of the meniscus remains a challenge. Current repair techniques, such as sutures and anchors, are effective in stabilizing the peripheral, vascularized regions of the meniscus, but are not adequate for promoting healing in the avascular region. The purpose of this study was to demonstrate the healing ability of a tissue-engineered repair technique using allogenic chondrocytes from three different sources for the avascular zone of the meniscus. MATERIAL AND METHODS: Articular, auricular, and costal chondrocytes were harvested from 3-month-old Yorkshire swine. A 1-cm bucket-handle lesion was created in the avascular zone of each three swine. A cell-scaffold construct, composed of a single chondrocyte cell type and Vicryl mesh, was implanted into the lesion and secured with two vertical mattress sutures. Controls consisted of each three sutured unseeded mesh implants, suture only, and untreated lesions. The swine were allowed immediate post-operative full weight bearing. Menisci and controls were harvested after 12 weeks. RESULTS: In all experimental samples, lesion closure was observed. Gross mechanical testing with two Adson forceps demonstrated bonding of the lesion. Histological analysis showed formation of new tissue in all three experimental samples. None of the control samples demonstrated closure and formation of new matrix. CONCLUSION: We present preliminary data that demonstrates the potential of a tissue-engineered, allogenic cellular repair to provide successful healing of lesions in the avascular zone in a large animal model.
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Christian Weinand, Giuseppe M Peretti, Samuel B Adams, Lawrence J Bonassar, Mark A Randolph, Thomas J Gill (2006)  An allogenic cell-based implant for meniscal lesions.   Am J Sports Med 34: 11. 1779-1789 Nov  
Abstract: BACKGROUND: Meniscal tears in the avascular zones do not heal. Although tissue-engineering approaches using cells seeded onto scaffolds could expand the indication for meniscal repair, harvesting autologous cells could cause additional trauma to the patient. Allogenic cells, however, could provide an unlimited amount of cells. HYPOTHESIS: Allogenic cells from 2 anatomical sources can repair lesions in the avascular region of the meniscus. STUDY DESIGN: Controlled laboratory study. METHODS: Both autologous and allogenic chondrocytes were seeded onto a Vicryl mesh scaffold and sutured into a bucket-handle lesion created in the medial menisci of 17 swine. Controls consisted of 3 swine knees treated with unseeded implants and controls from a previous experiment in which 4 swine were treated with suture only and 4 with no treatment. Menisci were harvested after 12 weeks and evaluated histologically for new tissue and percentage of interface healing surface; they were also evaluated statistically. RESULTS: The lesions were closed in 15 of 17 menisci. None of the control samples demonstrated healing. Histologic analysis of sequential cuts through the lesion showed formation of new scar-like tissue in all experimental samples. One of 8 menisci was completely healed in the allogenic group and 2 of 9 in the autologous group; the remaining samples were partially healed in both groups. No statistically significant differences in the percentage of healing were observed between the autologous and allogenic cell-based implants. CONCLUSION: Use of autologous and allogenic chondrocytes delivered via a biodegradable mesh enhanced healing of avascular meniscal lesions. CLINICAL RELEVANCE: This study demonstrates the potential of a tissue-engineered cellular repair of the meniscus using autologous and allogenic chondrocytes.
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John M Mesa, Victor Zaporojan, Christian Weinand, Timothy S Johnson, Lawrence Bonassar, Mark A Randolph, Michael J Yaremchuk, Peter E Butler (2006)  Tissue engineering cartilage with aged articular chondrocytes in vivo.   Plast Reconstr Surg 118: 1. 41-9; discussion 50-3 Jul  
Abstract: BACKGROUND: Tissue engineering has the potential to repair cartilage structures in middle-aged and elderly patients using their own "aged" cartilage tissue as a source of reparative chondrocytes. However, most studies on tissue-engineered cartilage have used chondrocytes from postfetal or very young donors. The authors hypothesized that articular chondrocytes isolated from old animals could produce neocartilage in vivo as well as articular chondrocytes from young donors. METHODS: Articular chondrocytes from 8-year-old sheep (old donors) and 3- to 6-month-old sheep (young donors) were isolated. Cells were mixed in fibrin gel polymer at 40 x 10 cells/ml until polymerization. Cell-polymer constructs were implanted into the subcutaneous tissue of nude mice and harvested at 7 and 12 weeks. RESULTS: Samples and native articular cartilage controls were examined histologically and assessed biochemically for total DNA, glycosaminoglycan, and hydroxyproline content. Histological analysis showed that samples made with chondrocytes from old donors accumulated basophilic extracellular matrix and sulfated glycosaminoglycans around the cells in a manner similar to that seen in samples made with chondrocytes from young donors at 7 and 12 weeks. Biochemical analysis revealed that DNA, glycosaminoglycan, and hydroxyproline content increased in chondrocytes from old donors over time in a pattern similar to that seen with chondrocytes from young donors. CONCLUSIONS: This study demonstrates that chondrocytes from old donors can be rejuvenated and can produce neocartilage just as chondrocytes from young donors do when encapsulated in fibrin gel polymer in vivo. This study suggests that middle-aged and elderly patients could benefit from cartilage tissue-engineering repair using their own "aged" articular cartilage as a source of reparative chondrocytes.
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2004
Timothy S Johnson, Jian-Wei Xu, Victor V Zaporojan, John M Mesa, Christian Weinand, Mark A Randolph, Lawrence J Bonassar, Jonathan M Winograd, Michael J Yaremchuk (2004)  Integrative repair of cartilage with articular and nonarticular chondrocytes.   Tissue Eng 10: 9-10. 1308-1315 Sep/Oct  
Abstract: Articular chondrocytes can synthesize new cartilaginous matrix in vivo that forms functional bonds with native cartilage. Other sources of chondrocytes may have a similar ability to form new cartilage with healing capacity. This study evaluates the ability of various chondrocyte sources to produce new cartilaginous matrix in vivo and to form functional bonds with native cartilage. Disks of articular cartilage and articular, auricular, and costal chondrocytes were harvested from swine. Articular, auricular, or costal chondrocytes suspended in fibrin glue (experimental), or fibrin glue alone (control), were placed between disks of articular cartilage, forming trilayer constructs, and implanted subcutaneously into nude mice for 6 and 12 weeks. Specimens were evaluated for neocartilage production and integration into native cartilage with histological and biomechanical analysis. New matrix was formed in all experimental samples, consisting mostly of neocartilage integrating with the cartilage disks. Control samples developed fibrous tissue without evidence of neocartilage. Ultimate tensile strength values for experimental samples were significantly increased (p < 0.05) from 6 to 12 weeks, and at 12 weeks they were significantly greater (p < 0.05) than those of controls. We conclude that articular, auricular, and costal chondrocytes have a similar ability to produce new cartilaginous matrix in vivo that forms mechanically functional bonds with native cartilage.
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2000
Christian Weinand, Karl-Josef Prommersberger, Peter Hahn, Ricardo E Giunta, Hermann Krimmer (2000)  Strategy for defect coverage in extensive degloving and crush injuries of 4 fingers   Handchir Mikrochir Plast Chir 32: 6. 424-429 Nov  
Abstract: Severe crush injuries with avulsion require specific treatment strategies. Usually we find complete loss of soft tissue, nerves and vessels, where only tendons and parts of the phalanges are preserved. Primary reconstructive procedures are usually not possible due to the complexity of the injury with severely destroyed structures. Bone shortening should be avoided in order to maintain finger length and motion. Therefore, emergency soft-tissue coverage represents the first step. Later, sensibility and mechanical stability of the skin should be restored. In our clinic, seven patients with this injury pattern were treated. Three cases involved four finger crush-avulsion injuries. In all cases, we performed a primary soft-tissue coverage with a pedicled flap. In a second session, the skin areas of the first web space of both feet were transplanted as neurovascular flaps. With this strategy, a useful hand function could be restored. The functional results are described and advantages and disadvantages of various techniques discussed.
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Christian Weinand, Sylvia Müller, Siegfried Zabransky, Heidi Danker-Hopfe (2000)  Saarland Growth Study: analyses of body composition of children, aged 3 to 11 years. Measurement of height, weight, girth (abdomen, upper arm, calf) and skinfolds (triceps, biceps, subscapular,suprailiacal, abdominal) and bioelectric impedance (BIA)   Wien Med Wochenschr 150: 7. 140-144  
Abstract: This study aimed to set up current reference charts of anthropometric data in the Saarland. Only national and international data were available to be compared but no former Saarland charts could be found. In the period between 1994 and 1995 we investigated children of 3 to 11 years in a cross-sectional study. Therefore we measured body height, weight, circumferences, skinfolds and bioelectrical impedance (BIA). No significant gender differences were found for body height and weight. Boys of all groups of age showed bigger abdominal circumferences than girls of the same age. On the other hand upper-arm and calf-girth of younger girls were larger than that from boys. In higher age groups circumferences become rather equal. The skinfolds of Saarland girls are thicker than those of boys. The urban rural comparison indicated no significant differences. Nor was any social divergence found among the aforementioned parameters. Regarding height Saarland children are seen to be similar or somewhat shorter than those examined in national or international studies. By the way, in higher percentiles the children in our study were heavier. Thus high BMI values of our study are bigger compared with former studies. According to the definition of obesity by the ECOG almost 20 to 30% of our children are obese. The older children become the higher is the percentage of obesity. Comparing girls and boys, bioelectrical impedance shows higher values for girls. In higher age classes resistance levels gets smaller, in boys more so than in girls. Body fat estimated by a formula based on BIA test parameters yielded negative values. So we propose the use of sex- and age-specific raw charts of BIA test parameters.
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Siegfried Zabransky, Christian Weinand, Anke Schmidgen, Caroline Schafmeister, Sylvia Müller, Rita Hollinger-Philipp, Heidi Danker-Hopfe (2000)  Saarland Growth Study: percentile charts for height, weight, and body mass index (BMI) for boys and girls, 4-18 years old, in Saarland   Wien Med Wochenschr 150: 7. 145-152  
Abstract: In a cross-sectional study dating from april 94 to march 96 we have investigated length and weight of 2610 girls and 2865 boys (age 4-18 years) at nursery schools and schools in Saarland. Thus we could provide first normative data for this region of Germany. Compared with data that have been collected between 1968 and 1989 at Dortmund, Bonn, Hamm and Jena, we found an increase in height of 2 cm for girls and boys aged 15-18 years. Apart from this finding, no further differences have been observed. Compared with international data, 18-year-old females and males in Saarland show large body heights: their average heights were 169 and 182 cm, respectively. Unfortunately, body weight of children of the Saarland is high, too. Children in Saarland were on average 1.5-6.6 kg heavier than those of the Dortmund study or other international studies. Studies have revealed that, according to the ECOG criteria, people of the Saarland are more obese than in other European countries. As a consequence of our study we request an institution for auxology to be founded which enables immediate reaction. This not only implies medical view points but also practical aspects of daily life (e.g. height of chairs or tables at schools). It is important to note that no changes have been made so far. Standards for height and weight should be updated every ten years. This should be a collaborative task between public health services and pediatric endocrinologists.
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