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OBJECTIVE: To compare the clinical outcomes of using elastic intramedullary nail and plate to fix fibular fracture. METHODS: The 60 patients with tibiofibular fractures admitted from January 2015 to December 2022 were divided into two groups:intramedullary nail group and plate group, 30 cases each, intramedullary nail group was treated with elastic intramedullary nail fixation group, plate group was treated with steel plate and screw fixation group. Intramedullary nail group, there were 18 males and 12 females, aged from 22 to 75 years old with an average of (39.4±9.8) years old, including 24 cases of traffic accidents injury, 6 cases of falling injury, 23 cases of closed fractures, 7 cases of open fractures. Steel plate group, there were 15 males and 15 females, aged from 24 to 78 years old with an average of (38.6±10.2) years old. The 22 cases were injured by traffic accident, 8 cases were injured by falling. The 24 cases were closed fractures and 6 cases were open fractures. The operation time, intraoperative bleeding, American Orthopedic Foot and Ankle Society (AOFAS) ankle and hind foot scores, clinical healing time of fibula and the incidence of wound complications were compared between the two groups. RESULTS: The patients in both groups were followed up for 6 to 21 months, with an average of (14.0±2.8) months. Compared with plate group, intramedullary nail group had shorter operative time, less bleeding, shorter clinical healing time of fibula, and lower infection rate of incision, and the difference was statistically significant (P<0.05). There were 2 cases of delayed healing in intramedullary nail group, 1 case of nonunion in plate group, and 2 cases of delayed healing in plate group, and there was no statistically significant difference between the two groups (P>0.05). In the last follow-up, according to the AOFAS scoring standard, the ankle function in intramedullary nail group was excellent in 17 cases, good in 12 cases, fair in 1 case, with an average of (88.33±4.57) points, while in plate group, excellent in 16 cases, good in 10 cases, fair in 4 cases, with an average of (87.00±4.14) points;There was no statistical difference between the two groups (P>0.05). CONCLUSION: Elastic intramedullary nail has the advantages of short operation time, less intraoperative bleeding, short fracture healing time and less incision complications in the treatment of fibular fracture, which is worthy of clinical application.
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Clavos Ortopédicos , Placas Óseas , Peroné , Fracturas de la Tibia , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Peroné/lesiones , Peroné/cirugía , Fracturas de la Tibia/cirugía , Titanio , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Adulto Joven , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , AceroRESUMEN
Background and object: Mitotic count (MC) is a critical histological parameter for accurately assessing the degree of invasiveness in breast cancer, holding significant clinical value for cancer treatment and prognosis. However, accurately identifying mitotic cells poses a challenge due to their morphological and size diversity. Objective: We propose a novel end-to-end deep-learning method for identifying mitotic cells in breast cancer pathological images, with the aim of enhancing the performance of recognizing mitotic cells. Methods: We introduced the Dilated Cascading Network (DilCasNet) composed of detection and classification stages. To enhance the model's ability to capture distant feature dependencies in mitotic cells, we devised a novel Dilated Contextual Attention Module (DiCoA) that utilizes sparse global attention during the detection. For reclassifying mitotic cell areas localized in the detection stage, we integrate the EfficientNet-B7 and VGG16 pre-trained models (InPreMo) in the classification step. Results: Based on the canine mammary carcinoma (CMC) mitosis dataset, DilCasNet demonstrates superior overall performance compared to the benchmark model. The specific metrics of the model's performance are as follows: F1 score of 82.9%, Precision of 82.6%, and Recall of 83.2%. With the incorporation of the DiCoA attention module, the model exhibited an improvement of over 3.5% in the F1 during the detection stage. Conclusion: The DilCasNet achieved a favorable detection performance of mitotic cells in breast cancer and provides a solution for detecting mitotic cells in pathological images of other cancers.
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Objective: The objective of this research is to construct a method to alleviate the problem of sample imbalance in classification, especially for arrhythmia classification. This approach can improve the performance of the model without using data enhancement. Methods: In this study, we have developed a new Multi-layer Perceptron (MLP) block and have used a Weight Capsule (WCapsule) network with MLP combined with sequence-to-sequence (Seq2Seq) network to classify arrhythmias. Our work is based on the MIT-BIH arrhythmia database, the original electrocardiogram (ECG) data is classified according to the criteria recommended by the American Association for Medical Instrumentation (AAMI). Also, our method's performance is further evaluated. Results: The proposed model is evaluated using the inter-patient paradigm. Our proposed method shows an accuracy (ACC) of 99.88% under sample imbalance. For Class N, sensitivity (SEN) is 99.79%, positive predictive value (PPV) is 99.90%, and specificity (SPEC) is 99.19%. For Class S, SEN is 97.66%, PPV is 96.14%, and SPEC is 99.85%. For Class V, SEN is 99.97%, PPV is 99.07%, and SPEC is 99.94%. For Class F, SEN is 97.94%, PPV is 98.70%, and SPEC is 99.99%. When using only half of the training sample, our method shows that the SEN of Class N and V is 0.97% and 5.27% higher than the traditional machine learning algorithm. Conclusion: The proposed method combines MLP, weight capsule network with Seq2seq network, effectively addresses the problem of sample imbalance in arrhythmia classification, and produces good performance. Our method also shows promising potential in less samples.
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Diabetes Mellitus Tipo 2 , Contaminantes Ambientales , Ácidos Ftálicos , Humanos , Encuestas Nutricionales , Diabetes Mellitus Tipo 2/inducido químicamente , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Ácidos Ftálicos/toxicidad , Contaminantes Ambientales/toxicidadRESUMEN
BACKGROUND AND OBJECTIVES: Arrhythmia classification based on electrocardiograms (ECG) can enhance clinical diagnostic efficiency. However, due to the significant differences in the number of different categories of heartbeats, the performance of classes with fewer samples in arrhythmia classification have not met expectations under the inter-patient paradigm. This paper aims to mitigate the adverse effects of category imbalance and improve arrhythmia classification performance. METHODS: We constructed a novel dual attention hybrid network (DA-Net) for arrhythmia classification under sample imbalance, based on modified convolutional networks with channel attention (MCC-Net) and sequence-to-sequence network with global attention (Seq2Seq). The refined local features of the input heartbeat are first extracted by MCC-Net and then sent to Seq2Seq for further feature fusion. By applying local and global attention in the feature extraction and fusion parts, respectively, the method fully fuses low-level feature details and high-level context information and enhances the ability to extract discriminative features. RESULTS: Based on the MIT-BIH arrhythmia database, under the inter-patient paradigm without any data augmentation methods, the proposed method achieved 99.98% accuracy (ACC) for five categories. The various performance indicators are as follows: Class N: sensitivity (SEN) = 99.96%, specificity (SPEC) = 99.93%, positive predictive value (PPV) = 99.99%; Class S: SEN = 99.67%, SPEC = 99.98%, PPV = 99.56%; Class V: SEN = 100%, SPEC = 99.99%, PPV = 99.91%; Class F: SEN = 100%, PPV = 99.98%, SPEC = 97.17%. In further experiments simulating extreme cases, the model still achieved ACC of 99.54% and 98.91% in the three-category and five-category categories when the training sample size was much smaller than the test sample. CONCLUSIONS: Without any data augmentation methods, the proposed model not only alleviates the negative impact of class imbalance and achieves excellent performance in all categories but also provides a new approach for dealing with class imbalance in arrhythmia classification. Additionally, our method demonstrates potential in conditions with fewer samples.
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Arritmias Cardíacas , Redes Neurales de la Computación , Humanos , Arritmias Cardíacas/diagnóstico , Electrocardiografía , Frecuencia Cardíaca , Bases de Datos Factuales , Algoritmos , Procesamiento de Señales Asistido por ComputadorRESUMEN
Given that mung beans constitute a significant nutrient source in many cultures, it is worthwhile to investigate ways to improve their nutritional and functional properties. The effect of fermentation of mung beans by Bacillus subtilis subsp. natto was investigated in various reactor designs, including static, shaking flasks, and soft elastic tubular reactors (SETR). The results showed that all three processes might affect the substrate, resulting in changes in the protein and carbohydrate fractions. We noticed an increase in soluble protein and serine levels, which we attribute to the proteases produced during fermentation. Through XRD, FTIR, and DSC analyses, it was also discovered that whereas static and shaking flask fermentation might raise relative crystallinity and peak temperature, fermentation performed on the SETR decreased these values. It was also possible to notice that SETR might induce a change in the particle size distribution of the substrate through a complex impact of mechanical forces, mixing, and microbial activity, which could be helpful to some aspects of the process. To summarize, fermentation of mung beans by Bacillus. subtilis subsp. natto could be an attractive approach for producing a food ingredient with various functional and nutritional properties. Furthermore, the SETR has been shown to be a viable technique for dealing with high solid load substrates, whether as the reactor for the entire process or as a first stage/pre-treatment step, and its applicability in bioprocesses should be explored further.
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Blood cell detection is an essential branch of microscopic imaging for disease diagnosis. TE-YOLOF is an effective model for blood cell detection, and was recently found to have an outstanding trade-off between accuracy and model complexity. However, there is a lack of understanding of whether the dilated encoder in TE-YOLOF works well for blood cell detection. To address this issue, we perform a thorough experimental analysis and find the interesting fact that the dilated encoder is not necessary for TE-YOLOF to perform the blood cell detection task. For the purpose of increasing performance on blood cell detection, in this research, we use the attention mechanism to dominate the dilated encoder place in TE-YOLOF and find that the attention mechanism is effective to address this problem. Based upon these findings, we propose a novel approach, named Enhanced Channel Attention Module (ECAM), based on attention mechanism to achieve precision improvement with less growth on model complexity. Furthermore, we examine the proposed ECAM method compared with other tip-top attention mechanisms and find that the proposed attention method is more effective on blood cell detection task. We incorporate the spatial attention mechanism in CBAM with our ECAM to form a new module, which is named Enhanced-CBAM. We propose a new network named Enhanced Channel Attention Network (ENCANet) based upon Enhanced-CBAM to perform blood cell detection on BCCD dataset. This network can increase the accuracy to 90.3 AP while the parameter is only 6.5 M. Our ENCANet is also effective for conducting cross-domain blood cell detection experiments.
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Recuento de Células Sanguíneas , Humanos , Recuento de Células Sanguíneas/instrumentaciónRESUMEN
BACKGROUND: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare cause of abdominal pain. The aim of the study is to investigate the role of a new parameter, the ratio of the SMA diameter to the superior mesenteric vein (SMV) diameter (SMA/SMV) based on non-enhanced computed tomography (CT), in the early diagnosis of SISMAD. METHODS: In a registry study from December 2013 to June 2021, 97 abdominal pain SISMAD patients (SISMAD group) admitted to our hospital were enrolled. Meanwhile, the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group. Student's t-test, Wilcoxon rank-sum test, and Chi-square test were used to compare differences between the SISMAD and control groups. MedCalc was used to generate receiver operating characteristic (ROC) curve. RESULTS: A total of 291 abdominal pain patients, including 97 SISMAD patients and 194 non-SISMAD patients, were included in the current study. The maximum SMA diameter, perivascular exudation, and SMA/SMV based on non-enhanced CT were significant between the two groups (all P<0.05). ROC curves showed that for the maximum SMA diameter, the area under the curve (AUC), cut-off, sensitivity, and specificity were 0.926, 9.80, 93.8%, and 79.4%, respectively. For SMA/SMV, its AUC, cut-off, sensitivity, and specificity were 0.956, 0.83, 88.7%, and 92.3%, respectively. The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter (P<0.05). The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency (AUC=0.970). CONCLUSION: SMA/SMV may be a potential marker for SISMAD.
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To further prove the advantages of microwave-assisted water bath heating (MWH) in low-value fish processing, the effects of different heating methods (two heating stage method, high temperature section respectively using MWH1, MWH2, MWH3, WH-water heating, MH-microwave heating) on secondary and tertiary myosin structures, SDS-PAGE, surface morphology, scanning electron microscopy (SEM), and particle size distribution were compared and analyzed. The findings revealed that MH and MWH aided in the production of gel formations by promoting myosin aggregation. Myosin from silver carps demonstrated enhanced sulfhydryl group and surface hydrophobicity after MWH treatment, as well as a dense network structure. The distribution of micropores becomes more uniform when the microwave time is increased. Actually, the total effect of microwave time on myosin is not substantially different. The correlation between particle size distribution and protein aggregation was also studied, in terms of time savings, the MWH of short microwave action is preferable since it not only promotes myosin aggregation but also avoids the drawbacks of a rapid warming rate. These discoveries give a theoretical foundation for understanding silver carp myosin under microwave modification, which is critical in the food industry.
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Based on a three-dimensional hydro-biogeochemical model, the compound and individual impacts of two types of human activities, i.e., land reclamation and land-based pollutant input, on coastal water quality were studied. In Qinzhou Bay (QZB), China, a total of 38.90 km2 of tidal flat was reclaimed between 2004 and 2019, and the Chemical Oxygen Demand (COD) in the wastewater was reduced by over 40%. However, the Dissolved Inorganic Nitrogen (DIN) was increased by above 40%, and the Dissolved Inorganic Phosphorus (DIP) was increased by about 17%, leading to the continuous deterioration of water quality in QZB. Correspondingly, the model results show that the bay's average COD decreased by 6.86%, but the DIN and DIP increased by 57.53% and 17.39%, respectively. Considering the individual effects, land reclamation contributed 72.73%, 75.38%, and 25.01% to the changes in the COD, DIN, and DIP concentrations in QZB, respectively; and the remainder was caused by the variations in the land-based pollutant input. By considering the compound effect of these two types of human activities, it was found that land reclamation can hinder the water quality improvement induced by the decrease in land-based pollutant input; and it can intensify the water quality deterioration induced by the increase in land-based pollutant input. These results indicate that the impact of land-based pollutant input on coastal water quality was modulated by land reclamation. However, the modulation did not affect the DIP since the phosphorus was the restrictive element in QZB. The comparison of different experimental results revealed that restoring hydrodynamics to enhance the bay-shelf exchange would be a more effective method of ecological restoration than solely reducing the pollutant input.
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Contaminantes Ambientales , Calidad del Agua , Bahías/química , China , Monitoreo del Ambiente , Humanos , Nitrógeno/análisis , Fósforo/análisisRESUMEN
OBJECTIVE: To investigate the clinical effect of vancomycin bone cement in the treatment of diabetic foot ulcer (DFU) ruptured Wagner gradeâ ¡-â £. METHODS: From March 2019 to April 2021, 32 patients with Wagner gradeâ ¡-â £ diabetic foot were divided into vacuum sealing drainage (VSD) group and bone cement group according to different treatment methods. There were 16 cases in VSD group, 8 males and 8 females;the age ranged from 66 to 81 (70.50±7.20) years, and the course of disease ranged from 8 to 40 (27.56±8.55) months;Wagner gradeâ ¡in 2 cases, grade â ¢in 7 cases and grade â £in 7 cases;debridement and VSD were used. There were 16 cases in the bone cement group, 9 males and 7 females;the age ranged from 63 to 79 (69.56±7.29) years, and the course of disease ranged from 11 to 39(22.75±11.43) months;Wagner gradeâ ¡ in 2 cases, grade â ¢in 5 cases and grade â £ in 9 cases;vancomycin loaded bone cement was used for treatment. The types of bacteria, negative time of bacterial culture, skin healing time, hospital stay, operation times and complications were observed and compared between two groups. RESULTS: All patients were followed up for 3 to 6 (4.00±1.07) months. The bacterial negative time, skin healing time and hospital stay in bone cement group were significantly lower than those in VSD group (P<0.05). The median number of operations in both groups was 2, and there was no significant difference (P>0.05). According to the analysis of pathogens in two groups, there were 13 cases of G+ patients, 14 cases of G- patients and 5 cases of mixed bacteria. The number of G+, G- and mixed bacteria in bone cement group was 6, 7 and 3 cases respectively, and the number of G+, G- and mixed bacteria in VSD group was 7, 7 and 2 cases respectively. The wounds of 32 patientsin two groups healed completely without complications. CONCLUSION: Vancomycin loaded bone cement is effective in the treatment of Wagner grade â ¡-â £ diabetic foot ulceration wounds. It can reduce the length of hospital stay, shorten the healing time of skin and kill pathogens as soon as possible. It is one of the effective methods to treat Wagner gradeâ ¡-â £diabetic foot ulceration.
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Diabetes Mellitus , Pie Diabético , Cementos para Huesos/uso terapéutico , Niño , Preescolar , Pie Diabético/tratamiento farmacológico , Femenino , Humanos , Masculino , Resultado del Tratamiento , Vancomicina , Cicatrización de HeridasRESUMEN
This paper extends robust principal component analysis (RPCA) to nonlinear manifolds. Suppose that the observed data matrix is the sum of a sparse component and a component drawn from some low dimensional manifold. Is it possible to separate them by using similar ideas as RPCA? Is there any benefit in treating the manifold as a whole as opposed to treating each local region independently? We answer these two questions affirmatively by proposing and analyzing an optimization framework that separates the sparse component from the manifold under noisy data. Theoretical error bounds are provided when the tangent spaces of the manifold satisfy certain incoherence conditions. We also provide a near optimal choice of the tuning parameters for the proposed optimization formulation with the help of a new curvature estimation method. The efficacy of our method is demonstrated on both synthetic and real datasets.
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BACKGROUND: X-linked Charcot-Marie-Tooth type 1 (CMT1X) disease is one of the most common forms of inherited neuropathy caused by mutations in the gap junction beta-1 protein (GJB1) gene (also known as connexin 32). This study presented the clinical and genetic features of a series of Chinese patients with GJB1 gene mutations. METHODS: A total of 22 patients from unrelated families, who were referred to Department of Neurology, Peking University First Hospital from January 2005 to January 2016, were identified with GJB1 mutations. Their clinical records and laboratory findings were retrospectively collected and reviewed. Mutations in the GJB1 gene were analyzed by targeted next-generation sequencing (NGS). Nucleotide alternations were confirmed with Sanger sequencing. RESULTS: The CMT1X patients predominantly showed distal muscle weakness of lower limbs with mild sensory disturbance. The mean age of onset was 15.6 ± 8.7 years (ranging from 1 year to 42 years). The sudden onset of cerebral symptoms appeared in four patients (18.2%); two were initial symptoms. One case had constant central nervous system (CNS) signs. There were 19 different heterozygous mutations, including 15 known mutations and four novel mutations (c.115G>T, c.380T>A, c.263C>A, and c.818_819insGGGCT). Among the 22 Chinese patients with CMT1X, the frequency of the GJB1 mutation was 4.5% in transmembrane domain 1 (TM1), 4.5% in TM2, 22.7% in TM3, 9.1% in TM4, 4.5% in extracellular 1 (EC1), 27.3% in EC2, 9.1% in intracellular loop, 13.6% in the N-terminal domain, and 4.5% in the C-terminal domain. CMT1X with CNS impairment appeared in five (22.7%) of these patients. CONCLUSIONS: This study indicated that CNS impairment was not rare in Chinese CMT1X patients. Mutations in the EC2 domain of the GJB1 gene were hotspot in Chinese CMT1X patients.
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Enfermedad de Charcot-Marie-Tooth/genética , Conexinas/genética , Adolescente , Adulto , Sistema Nervioso Central/metabolismo , Enfermedad de Charcot-Marie-Tooth/patología , Niño , Preescolar , Análisis Mutacional de ADN , Electrofisiología , Femenino , Genotipo , Humanos , Lactante , Masculino , Mutación , Fenotipo , Estudios Retrospectivos , Adulto Joven , Proteína beta1 de Unión ComunicanteRESUMEN
BACKGROUND: Dysferlinopathy is caused by mutations in the dysferlin (DYSF) gene. Here, we described the genetic features of a large cohort of Chinese patients with this disease. METHODS: Eighty-nine index patients were included in the study. DYSF gene analysis was performed by Sanger sequencing in 41 patients and targeted next generation sequencing (NGS) in 48 patients. Multiplex ligation-dependent probe amplification (MLPA) was performed to detect exon duplication/deletion in patients with only one pathogenic mutation. RESULTS: Among the 89 index patients, 79 patients were demonstrated to carry two disease-causing (73 cases) or possibly disease-causing mutations (6 cases), including 26 patients with homozygous mutations. We identified 105 different mutations, including 59 novel ones. Notably, in 13 patients in whom only one pathogenic mutation was initially found by Sanger sequencing or NGS, 3 were further identified to carry exon deletions by MLPA. The mutations identified in this study appeared to cluster in the N-terminal region. Mutation types included missense mutations (30.06%), nonsense mutations (17.18%), frameshift mutations (30.67%), in-frame deletions (2.45%), intronic mutations (17.79%), and exonic rearrangement (1.84%). No genotype-phenotype correlation was identified. CONCLUSIONS: DYSF mutations in Chinese patients clustered in the N-terminal region of the gene. Exonic rearrangements were found in 23% of patients with only one pathogenic mutation identified by Sanger sequencing or NGS. The novel mutations found in this study greatly expanded the mutational spectrum of dysferlinopathy.
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Proteínas de la Membrana/genética , Proteínas Musculares/genética , Distrofia Muscular de Cinturas/genética , Adolescente , Adulto , Pueblo Asiatico , Niño , China , Codón sin Sentido/genética , Disferlina , Exones/genética , Femenino , Mutación del Sistema de Lectura/genética , Frecuencia de los Genes/genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Mutación Missense/genética , Fenotipo , Adulto JovenRESUMEN
OBJECTIVE: To explore clinical and muscular pathological features of statin-induced myopathy. METHODS: Nine patients were enrolled in this study, who were diagnosed as statin-induced myopathy by muscle biopsy in Peking University First Hospital from April, 2012 to October, 2014. The clinical data and pathological findings were analyzed. RESULTS: The exposure time to statins varied from 4 days to 4 years in the total of 9 patients, 6 males and 3 females, with the average age of 63 ± 6 (55 to 74) years old. Three patients suffered from myalgia and 6 patients complained of weakness mainly at the proximal limbs, while no symptoms occured in 3 patients. Serum creatine kinase (CK) increased in all patients with the maximum value varied from 468 to 8 000 U/L. Serum myositis antibodies were tested in 7 patients and all were negative. Electromyogram was performed in six patients with myogenic damage found in 2 patients. MRI of bilateral thigh muscle was carried out in six patients with muscle edema and mild fatty infiltration found in 2 patients. All patients underwent skeletal muscle biopsy with histochemical and immunohistochemical staining. The main muscular pathological features were muscle fiber atrophy, necrosis, regeneration and increased lipid droplets. Ragged blue fiber, cytochrome C oxidase-negative muscle fibers and decreased NADH activity were observed in some patients. MHC-I expressed in the sarcolemma of muscle fibers at various levels. Mild C5b-9 staining was found in the endomysium, capillary and cytoplasm. Symptoms and the level of CK were improved in 7 patients after discontinuing statins or changing to another statin, while the immunosuppressive therapy were used in 2 patients and shown to be effective. CONCLUSIONS: Statin induced myopathy is self-limiting in most patients, with improvement after discontinuation of statins. Few patients with autoimmune necrotic myopathy need immunosuppressive therapy.
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Creatina Quinasa/sangre , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Enfermedades Musculares/inducido químicamente , Miositis/sangre , Beijing , Biopsia , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Músculo Esquelético/patología , Enfermedades Musculares/patología , NecrosisRESUMEN
BACKGROUND: Mutations of transthyretin (TTR) cause the most common type of autosomal-dominant hereditary systemic amyloidosis, which occurs worldwide. To date, more and more mutations in the TTR gene have been reported. Some variations in the clinical presentation are often observed in patients with the same mutation or the patients in the same family. The purpose of this study was to find out the clinicopathologic and genetic features of Chinese patients with hereditary TTR amyloidosis. METHODS: Clinical and necessary examination materials were collected from nine patients of eight families with hereditary TTR amyloidosis at Peking University First Hospital from January 2007 to November 2014. Sural nerve biopsies were taken for eight patients and skin biopsies were taken in the calf/upper arm for two patients, for light and electron microscopy examination. The TTR genes from the nine patients were analyzed. RESULTS: The onset age varied from 23 to 68 years. The main manifestations were paresthesia, proximal and/or distal weakness, autonomic dysfunction, cardiomyopathy, vitreous opacity, hearing loss, and glossohypertrophia. Nerve biopsy demonstrated severe loss of myelinated fibers in seven cases and amyloid deposits in three. One patient had skin amyloid deposits which were revealed from electron microscopic examination. Genetic analysis showed six kinds of mutations of TTR gene, including Val30Met, Phe33Leu, Ala36Pro, Val30Ala, Phe33Val, and Glu42Gly in exon 2. CONCLUSIONS: Since the pathological examinations of sural nerve were negative for amyloid deposition in most patients, the screening for TTR mutations should be performed in all the adult patients, who are clinically suspected with hereditary TTR amyloidosis.