Improved visualization of median, ulnar nerves, and small branches in the wrist and palm using contrast-enhanced magnetic resonance neurography.

Background: Magnetic resonance imaging of peripheral nerves in the wrist and palm is challenging due to the small size, tortuous course, complex surrounding tissues, and accompanying blood vessels. The occurrence of carpal palmar lesions leads to edema, swelling, and mass effect, which may further interfere with the display and identification of nerves. Objective: To evaluate whether contrast-enhanced magnetic resonance neurography (ceMRN) improves the visualization of the morphology and pathology of the median, ulnar nerves, and their small branches in the wrist and palm. Design: An observational study. Methods: In total 57 subjects, including 36 volunteers and 21 patients with carpal palmar lesions, were enrolled and underwent ceMRN and non-contrast MRN (ncMRN) examination at 3.0 Tesla. The degree of vascular suppression, nerve visualization, diagnostic confidence, and lesion conspicuity was qualitatively assessed by two radiologists. Kappa statistics were obtained for inter-reader agreement. The signal-to-noise ratio, contrast ratio (CR), and contrast-to-noise ratio (CNR) of the median nerve were measured. The subjective ratings and quantitative measurements were compared between ncMRN and ceMRN. Results: The inter-reader agreement was excellent (k > 0.8) for all qualitative assessments and visualization assessment of each nerve segment. Compared with ncMRN, ceMRN significantly improved vascular suppression in volunteers and patients (both p < 0.001). The ceMRN significantly enhanced nerve visualization of each segment (all p < 0.05) and diagnostic confidence in volunteers and patients (both p < 0.05). The ceMRN improved lesion conspicuity (p = 0.003) in patients. Quantitatively, ceMRN had significantly higher CRs of nerve versus subcutaneous fat, bone marrow, and vessels and CNR of nerve versus vessel than ncMRN (all p < 0.05). Conclusion: The ceMRN significantly improves the visualization of peripheral nerves and pathology in the wrist and palm by robustly suppressing the signals of fat, bone marrow, and especially vessels in volunteers and patients.

Study on the improvement of magnetic resonance imaging and lesion display of small nerves in the wrist and palm using contrast agents Why was the study done? Because the nerves and branches in the wrist and palm are numerous, small, tortuous, and surrounded by muscles, fat, bones, blood vessels and other tissues, it is difficult to show their complete shape with conventional magnetic resonance imaging. Hand lesions often lead to swelling, edema and masses, which interfere with the display of nerves. Therefore, it is difficult to directly diagnose the relationship between the lesions and nerves in clinical practice. What did the researchers do? The research team used contrast agent plus three-dimensional high-resolution magnetic resonance sequence to display the nerves of volunteers and patients with hand lesions, and used subjective and objective evaluation methods to compare the display effect of the sequence on the nerves before and after the use of contrast agent. What did the researchers find? The imaging method of contrast agent plus three-dimensional high-resolution magnetic resonance sequence can reduce the interference of fat, blood vessels, etc. on nerve display, improve the display effect of each nerve segment of the wrist and palm, increase readers' confidence in identifying nerves, and improve the detection of lesions. What do the findings mean? This study verified the feasibility and advantages of using contrast agents for magnetic resonance imaging of nerves in the wrist and palm. It provides a new method for clinical and imaging diagnosis of hand lesions, which can simultaneously display the morphological characteristics of nerves and lesions, reducing the difficulty of clinical diagnosis and improving the efficiency of imaging diagnosis.

Comparison of the Short-Term Clinical Effectiveness of 5% Dextrose Water, Platelet-rich Plasma and Corticosteroid Injections for Carpal Tunnel Syndrome: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: To compare the short-term effectiveness of corticosteroids, 5% dextrose (D5W), and platelet-rich plasma (PRP) injections for treating carpal tunnel syndrome (CTS). DATA SOURCES: Four databases (MEDLINE [PubMed], Embase, the Cochrane Controlled Trials Register, and Web of Science [WOS]) were researched from inception to the first of April 2022. STUDY SELECTION: Two authors independently screened the literature to identify the RCTs meeting the included criteria, which involved comparing corticosteroid, 5% dextrose water (D5W), and PRP injection with each other or placebo-controlled for treating CTS. DATA EXTRACTION: The 2 reviewers independently conducted information extraction, the utcomes included were the changes in Symptom Severity Scale, Functional Status Scale, and Visual Analog Scale at short-term follow-up after drug injection treatment and any adverse events reported. DATA SYNTHESIS: Twelve randomized controlled trials with 749 patients (817 hands) were included. The results of this study suggested that PRP injection was the most likely to relieve symptoms, improve functions, and alleviate pain, with the surface under the cumulative ranking curve being 91.5%, 92.7%, and 80.8%, respectively, after D5W injection (74.4%, 72.2%, 72.1%), and corticosteroid injection (33.7%, 31.9%, 46.2%). The injection of 3 drugs was significantly better than that of a placebo. CONCLUSIONS: From the results of the network meta-analysis, PRP injection is the most recommended treatment among the injection of corticosteroid, D5W, and PRP.

Deep learning models for predicting the survival of patients with chondrosarcoma based on a surveillance, epidemiology, and end results analysis.

Background: Accurate prediction of prognosis is critical for therapeutic decisions in chondrosarcoma patients. Several prognostic models have been created utilizing multivariate Cox regression or binary classification-based machine learning approaches to predict the 3- and 5-year survival of patients with chondrosarcoma, but few studies have investigated the results of combining deep learning with time-to-event prediction. Compared with simplifying the prediction as a binary classification problem, modeling the probability of an event as a function of time by combining it with deep learning can provide better accuracy and flexibility. Materials and methods: Patients with the diagnosis of chondrosarcoma between 2000 and 2018 were extracted from the Surveillance, Epidemiology, and End Results (SEER) registry. Three algorithms-two based on neural networks (DeepSurv, neural multi-task logistic regression [NMTLR]) and one on ensemble learning (random survival forest [RSF])-were selected for training. Meanwhile, a multivariate Cox proportional hazards (CoxPH) model was also constructed for comparison. The dataset was randomly divided into training and testing datasets at a ratio of 7:3. Hyperparameter tuning was conducted through a 1000-repeated random search with 5-fold cross-validation on the training dataset. The model performance was assessed using the concordance index (C-index), Brier score, and Integrated Brier Score (IBS). The accuracy of predicting 1-, 3-, 5- and 10-year survival was evaluated using receiver operating characteristic curves (ROC), calibration curves, and the area under the ROC curves (AUC). Results: A total of 3145 patients were finally enrolled in our study. The mean age at diagnosis was 52 ± 18 years, 1662 of the 3145 patients were male (53%), and mean survival time was 83 ± 67 months. Two deep learning models outperformed the RSF and classical CoxPH models, with the C-index on test datasets achieving values of 0.832 (DeepSurv) and 0.821 (NMTLR). The DeepSurv model produced better accuracy and calibrated survival estimates in predicting 1-, 3- 5- and 10-year survival (AUC:0.895-0.937). We deployed the DeepSurv model as a web application for use in clinical practice; it can be accessed through https://share.streamlit.io/whuh-ml/chondrosarcoma/Predict/app.py. Conclusions: Time-to-event prediction models based on deep learning algorithms are successful in predicting chondrosarcoma prognosis, with DeepSurv producing the best discriminative performance and calibration.

One-year mortality and consequences of COVID-19 in cancer patients: A cohort study.

The 1-year mortality and health consequences of COVID-19 in cancer patients are relatively underexplored. In this multicenter cohort study, 166 COVID-19 patients with cancer were compared with 498 non-cancer COVID-19 patients and 498 non-COVID cancer patients. The 1-year all-cause mortality and hospital mortality rates in Cancer COVID-19 Cohort (30% and 20%) were significantly higher than those in COVID-19 Cohort (9% and 8%, both P < .001) and Cancer Cohort (16% and 2%, both P < 0.001). The 12-month all-cause post-discharge mortality rate in survival discharged Cancer COVID-19 Cohort (8%) was higher than that in COVID-19 Cohort (0.4%, P < .001) but similar to that in Cancer Cohort (15%, P = .084). The incidence of sequelae in Cancer COVID-19 Cohort (23%, 26/114) is similar to that in COVID-19 Cohort (30%, 130/432, P = .13). The 1-year all-cause mortality was high among patients with hematologic malignancies (59%), followed by those who have nasopharyngeal, brain, and skin tumors (45%), digestive system neoplasm (43%), and lung cancers (32%). The rate was moderate among patients with genitourinary (14%), female genital (13%), breast (11%), and thyroid tumors (0). COVID-19 patients with cancer showed a high rate of in-hospital mortality and 1-year all-cause mortality, but the 12-month all-cause post-discharge mortality rate in survival discharged cancer COVID-19 patients was similar to that in Cancer Cohort. Comparing to COVID-19 Cohort, risk stratification showed that hematologic, nasopharyngeal, brain, digestive system, and lung tumors were high risk (44% vs 9%, P < 0.001), while genitourinary, female genital, breast, and thyroid tumors had moderate risk (10% vs 9%, P = .85) in COVID-19 Cancer Cohort. Different tumor subtypes had different effects on COVID-19. But if cancer patients with COVID-19 manage to survive their COVID-19 infections, then long-term mortality appears to be similar to the cancer patients without COVID-19, and their long-term clinical sequelae were similar to the COVID-19 patients without cancer.

Skin Epidermis and Adnexa Regrowth Induced by Treatment With Artificial Dermal Template After Full-Thickness Skin Wound.

Full-thickness skin wounds are common accidents. Although healing can be achieved by treatments like autologous skin grafts, donor site morbidity is hardly evitable. In this article, we provide compelling evidence demonstrating that artificial dermal template (ADT)-treated wound healing is achieved by regrowth of skin epidermis as well as adnexa without skin grafts by use of rodent models. First, by fixating a chamber to the wound edge, we confirmed that wound healing was achieved by regeneration instead of contracture. We found highly proliferative cells in adnexa in the newly formed skin. In the distal edge of newly formed skin, we identified immature hair follicles at early developing stages, suggesting they were newly regenerated. Second, we observed that the Lgr5-positive hair follicle stem cells contributed to formation of new hair follicles through a lineage tracing model. Also, Lgr6-positive cells were enriched in distal edge of newly developed skin. Finally, WNT signaling pathway mediators were highly expressed in the new skin epidermis and adnexa, implying a potential role of WNT signaling during ADT treatment-stimulated skin regrowth. Taken together, our findings demonstrated that full skin regrowth can be induced by ADT treatment alone, thus arguing for its wide clinical application in skin wound treatment.

One-stage wound healing of fingertip injuries induced by treatment of artificial dermis.

BACKROUND: Fingertip injuries are common in both adults and children. Many operative and non-operative management techniques have been reported to restore the function and cosmetic shape of fingertips after injuries. Although these methods may be used for different indications in clinical settings, few of them can treat all kinds of fingertip injuries. In addition, there is controversy as to whether the surgical approach or the conservative approach is the optimal management for fingertip injuries. METHODS: Thirty-six fingers of 33 patients with fingertip injuries were included in the study. All wounds were treated with surgical debridement and artificial dermis coverage without further surgical treatment. Follow-up duration was 24.5 months on average. RESULTS: All injuries were categorised into four types - Allen's classification of fingertip injury type II, type III, type IV, and transverse amputations proximal to the lunula and close to the level of the distal interphalangeal (DIP) joint - and 28 of them had bone exposure. The defects of all fingers were restored in one stage within an average of 8 weeks. Although the length and width of the new fingertips were less than those of the contralateral fingertips, almost all patients were satisfied with the functional and cosmetic outcomes of their regenerated fingers. CONCLUSIONS: One-stage wound healing of fingertip injuries induced by artificial dermis treatment is an easy and effective approach to restoring defects after injury with excellent functional and cosmetic results. Nearly all kinds of fingertip injuries can be managed with this method without any further surgical treatment. Therefore, this is a good alternative for the management of fingertip injuries.

Transposition of branches of radial nerve innervating supinator to posterior interosseous nerve for functional reconstruction of finger and thumb extension in 4 patients with middle and lower trunk root avulsion injuries of brachial plexus.

This study aimed to investigate the reconstruction of the thumb and finger extension function in patients with middle and lower trunk root avulsion injuries of the brachial plexus. From April 2010 to January 2015, we enrolled in this study 4 patients diagnosed with middle and lower trunk root avulsion injuries of the brachial plexus via imaging tests, electrophysiological examinations, and clinical confirmation. Muscular branches of the radial nerve, which innervate the supinator in the forearm, were transposed to the posterior interosseous nerve to reconstruct the thumb and finger extension function. Electrophysiological findings and muscle strength of the extensor pollicis longus and extensor digitorum communis, as well as the distance between the thumb tip and index finger tip, were monitored. All patients were followed up for 24 to 30 months, with an average of 27.5 months. Motor unit potentials (MUP) of the extensor digitorum communis appeared at an average of 3.8 months, while MUP of the extensor pollicis longus appeared at an average of 7 months. Compound muscle action potential (CMAP) appeared at an average of 9 months in the extensor digitorum communis, and 12 months in the extensor pollicis longus. Furthermore, the muscle strength of the extensor pollicis longus and extensor digitorum communis both reached grade III at 21 months. Lastly, the average distance between the thumb tip and index finger tip was 8.8 cm at 21 months. In conclusion, for patients with middle and lower trunk injuries of the brachial plexus, transposition of the muscular branches of the radial nerve innervating the supinator to the posterior interosseous nerve for the reconstruction of thumb and finger extension function is practicable and feasible.

Sirtuin 6 prevents matrix degradation through inhibition of the NF-κB pathway in intervertebral disc degeneration.

Intervertebral disc degeneration (IDD) is marked by imbalanced metabolism of the extracellular matrix (ECM) in the nucleus pulposus (NP) of intervertebral discs. This study aimed to determine whether sirtuin 6 (SIRT6), a member of the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases, protects the NP from ECM degradation in IDD. Our study showed that expression of SIRT6 markedly decreased during IDD progression. Overexpression of wild-type SIRT6, but not a catalytically inactive mutant, prevented IL-1ß-induced NP ECM degradation. SIRT6 depletion by RNA interference in NP cells caused ECM degradation. Moreover, SIRT6 physically interacted with nuclear factor-κB (NF-κB) catalytic subunit p65, transcriptional activity of which was significantly suppressed by SIRT6 overexpression. These results suggest that SIRT6 prevented NP ECM degradation in vitro via inhibiting NF-κB-dependent transcriptional activity and that this effect depended on its deacetylase activity.

Common genetic variants in the microRNA biogenesis pathway are associated with malignant peripheral nerve sheath tumor risk in a Chinese population.

PURPOSE: The role of microRNAs (miRNAs) in tumorigenesis has been well established. Genetic variants in the miRNA biogenesis pathway genes may modify cancer development and survival by affecting the miRNA biogenesis. Our aim is to investigate the association of polymorphisms in the miRNA biogenesis pathway genes and malignant peripheral nerve sheath tumor (MPNST) risk among neurofibromatosis type 1 (NF1) patients. METHODS: A case-control study was performed to analyze 53 SNPs in 11 miRNA biogenesis pathway genes in 356 patients (200 patients with NF1 and 156 patients with both NF1 and MPNST) in China. Association analysis was performed in an additive genetic model by logistics regression. RESULTS: Four SNPs (DDX5 rs1991401, OR=1.79, 95% CI, 1.34-2.38, P=7.90 × 10(-5); DROSHA rs10719, OR=1.64, 95% CI, 1.23-2.20, P=8.76 × 10(-4); AGO2 rs7005286, OR=0.48, 95% CI, 0.32-0.72, P=3.46 × 10(-4); GEMIN4 rs7813, OR=0.50, 95% CI, 0.34-0.72, P=2.65 × 10(-4)) were significantly associated with MPNST risk. A strong gene-dose effect with increased MPNST risk (P for trend<0.001) was observed. CONCLUSIONS: Genetic variants in the miRNA biogenesis pathway genes may modify MPNST risk both individually and jointly.

TGF-ß1-induced synthesis of collagen fibers in skeletal muscle-derived stem cells.

The aim of this study was to investigate the mechanism of deposition of extracellular matrix induced by TGF-ß1 in skeletal muscle-derived stem cells (MDSCs). Rat skeletal MDSCs were obtained by using preplate technique, and divided into four groups: group A (control group), group B (treated with TGF-ß1, 10 ng/mL), group C (treated with TGF-ß1 and anti-connective tissue growth factor (CTGF), both in 10 ng/mL), and group D (treated with anti-CTGF, 10 ng/mL). The expression of CTGF, collagen type-I (COL-I) and collagen type-III (COL-III) in MDSCs was examined by using RT-PCR, Western blot and immunofluorescent stain. It was found that one day after TGF-ß1 treatment, the expression of CTGF, COL-I and COL-III was increased dramatically. CTGF expression reached the peak on the day 2, and then decreased rapidly to a level of control group on the day 5. COL-I and COL-III mRNA levels were overexpresed on the day 2 and 3 respectively, while their protein expression levels were up-regulated on the day 2 and reached the peak on the day 7. In group C, anti-CTGF could partly suppress the overexpression of COL-I and COL-II induced by TGF-ß1 one day after adding CTGF antibody. It was concluded that TGF-ß1 could induce MDSCs to express CTGF, and promote the production of COL-I and COL-III. In contrast, CTGF antibody could partially inhibit the effect of TGF-ß1 on the MDSCs by reducing the expression of COL-I and COL-III. Taken together, we demonstrated that TGF-ß1-CTGF signaling played a crucial role in MDSCs synthesizing collagen proteins in vitro, which provided theoretical basis for exploring the methods postponing skeletal muscle fibrosis after nerve injury.

Identification of serum microRNAs in genome-wide serum microRNA expression profiles as novel noninvasive biomarkers for malignant peripheral nerve sheath tumor diagnosis.

Recent studies found that serum microRNAs (miRNAs) could serve as stable and noninvasive biomarkers for disease diagnosis. We used genome-wide serum miRNA expression analysis to investigate the role of serum miRNAs in distinguishing malignant peripheral nerve sheath tumor (MPNST) patients with and without neurofibromatosis type 1 (NF1) from NF1 patients. A total of 100 patients with NF1, 93 sporadic MPNST patients, and 71 NF1 MPNST patients were enrolled in this two-stage, case-control study. Solexa sequencing was used to screen for miRNAs that expressed differentially in three pooled serum samples from 10 NF1 patients, 10 sporadic MPNST patients, and 10 NF1 MPNST patients. The detected serum miRNAs then were validated in 90 patients with NF1, 83 patients with sporadic MPNST, and 61 NF1 MPNST patients by individual quantitative reverse transcriptase polymerase chain reaction assays. Eight serum miRNAs altered more than fivefold by Solexa sequencing between MPNST patients (with and without NF1) and NF1 patients. MiR-801 and miR-214 increased both in sporadic MPNST patients and NF1 MPNST patients when compared with NF1 patients. The sensitivity and the specificity of sporadic MPNST detection by the two-miRNA signature were 0.747 and 0.856, respectively. MiR-24 was only significantly up-regulated in NF1 MPNST patients. The combination of the three miRNAs (MiR-801, miR-214, and miR-24) could distinguish NF1 MPNST patients from NF1 patients with a sensitivity of 0.820 and a specificity of 0.844. The serum-based miRNA expression profiles could serve as novel noninvasive biomarkers in sporadic MPNST and NF1 MPNST detection.

Clinical study of treatment for recalcitrant ingrown toenail by partial distal phalanx removal.

The aim of this study was to identify putative aetiological factors of recalcitrant ingrown toenail and then to introduce a new surgical technique for its treatment on the basis of this identification. We found that many of our patients had an upturned morphology on the distal phalanx beneath the recalcitrant ingrown toenail. We thereby designed a new operative technique to treat this problem. From October 1997 to May 2006, 31 patients (38 toes), who were operated on using the new technique, were assigned to the experimental group. Another 38 patients, who were randomly selected from the population without an ingrown toenail, were assigned to the control group. Briefly, the operation is performed as follows: make an elliptical skin incision distal to the hyponychium. Remove the wedge of tissue through incision, together with the periosteum on the lateral side of the distal phalanx. Expose and then transect the distal part of the distal phalanx. Twenty-nine patients (36 toes) were included in the follow up which varied in length from 8 to 29 months. None of them had recurrent symptoms. In conclusion, an upturned abnormality of the distal phalanx may contribute, at least partly, to the formation of recalcitrant ingrown toenail. The partial distal phalanx removal could be considered as an effective technique in recalcitrant ingrown toenail therapy.

[Effect of transforming growth factor beta1 plasmid on frosted allogenic nerve transplantation].

OBJECTIVE: To study the effect of transforming growth factor beta1 (TGF-beta1) plasmid on poly frosted-defrosted allogenic nerve transplantation. METHODS: Forty Wistar rats were randomly divided into two groups equally. A 2.0 cm sciatic nerve segment, 5 mm away from infrapiriformis muscle space, was removed and the defect was repaired with poly frosted-defrosted allogenic nerve. The TGF-beta1 plasmids were injected into the nerve anastomosis and adjacent muscles in the experimental group, normal saline in the control group. The nerve specimens were sectioned for staining in the 6th and 12th weeks. Axonal count and statistical analyses were done. RESULTS: The grafted and distal nerve segments showed regenerated fibers in both groups. In the experimental group, less edema and more nerve fibers were observed in the 6th week. The grafted nerve segment was filled with regeneration axons, the myelinated nerve fibers arranged regularly, and the axons and the myelin sheaths developed well in the 12th week. There was significant difference in the number of regenerating axons between the experimental group 98.6 +/- 4.8/microm2 and control group 75.8 +/- 5.1/microm2 (P < 0.01). CONCLUSION: Multiple frost-defrost of allogenic nerve can reduce its antigenicity and increase its usefulness in repairing nerve defects. Local use of TGF-beta1 plasmid can enhance immunosuppression to reduce immuno rejection.

Protective effect of interleukin-1beta on motor neurons after sciatic nerve injury in rats.

Protective effect of interleukin-1beta (IL-1beta) on motor neurons was studied after peripheral nerve injury. Twenty Wistar rats were divided into 2 groups randomly. The right sciatic nerve of each rat was resected. After silicon tubulization of sciatic nerve in rat, 15 microl 1 ng/ml IL-1beta and PBS solution were injected into the silicon capsule respectively. Enzyme histochemistry was performed to show acetyle cholesterase (AchE) and nitric oxide staining (NOS) activity of spinal alpha motor neurons in spinal segments 2 weeks later. Neurons were counted and the diameter and cross sectional (c/s) area of neurons were analyzed by using computer image analysis system. The results showed that as compared with the normal side, both enzyme activities significantly changed in motor neurons in PBS group. The diameter and c/s area of both neurons changed significantly too (P < 0.01). These results suggest that exogenous IL-1beta protects alpha-motor neurons from degeneration and necrosis after peripheral nerve injury.

[Combined immunosuppression of FK506 and RS-61443 in rat limb allotransplantation].

OBJECTIVE: To study the immunosuppressive effect of combined therapy with FK506 and RS-61443 in rat limb allotransplantation. METHODS: A total of 101 male SD rats were randomly divided into seven groups and used as recipients, and 101 Wistar rats were used as donors. All SD rats were performed limb allotransplantation without using immunosuppressants in control group. In experimental groups (Groups 1-6), the recipients were immunosuppressed with various dosages of FK506, RS-61443 or FK506 + RS61443, after transplantation for 5 weeks. To evaluate the results, we observed circulation of the transplanted limb, the mean rejection time, the histologic grading of skin rejection of limb grafts and the survival time of limb grafts. RESULTS: The control group showed rejection signs (edema and erythema of the skin) after a mean time of 3.36 +/- 1.15 days, and the mean survival time of the allografts was only 7.00 +/- 0.78 days. In the groups only using FK506 or RS-61443, the survival time were prolonged to varying degrees, but rejection occurred even in the period of using drug. As dosage increased, the rejection could not be prevented and the damage to liver and kidney could be induced. In the group using FK506 in combination with RS-61443, only skin and muscle of limb allografts showed slight rejection sign, function of liver and kidney was not obviously affected, the mean survival time of limb allografts was prolonged to 58.76 +/- 6.81 days. CONCLUSIONS: A combination of FK506 and RS-61443 is a more potent immunosuppressive agent than FK506 oro RS-61443 in preventing the rejection of limb allografts, and it can obviously prolong the survival time of limb allografts.

The characteristics of acute rejection after limb allotransplantation in rats--an experimental study.

To study the characteristics of acute rejection after limb allotransplantation, 29 male Sprague-Dawley rats were randomly divided into 2 groups, with 15 rats in control group and 14 rats in experimental group. Each rat in control group underwent limb replantation. Each rat in experimental group received limb transplantation from Wistar rat. No immunosuppressive drugs were used after operation. The circulation of the transplanted limb, time and signs of rejection, histopathological changes in the tissues of the limb graft when rejected and survival time of limb grafts were evaluated. In the control group, no signs of rejection were observed, the circulation of each replanted limb was normal, it could survive for a longer time. The experimental group showed clinical signs of rejection (sub dermal edema and erythema) after a mean time of 3.36+/-1.15 days, and the mean survival time of the allografts was only 7+/-0.78 days. Histopathological examination showed most violent rejection reaction in skin. It is concluded that with Wistar-to-SD limb transplantation without use of immunosuppression, rejection of the grafts would occur after a mean time of 3.36+/-1.15 days; the earliest signs of rejection were edema and erythema of the skin, skin being the most representative component of limb graft rejection.