Metagenomics approach to identify lignocellulose-degrading enzymes in the gut microbiota of the Chinese bamboo rat cecum

BACKGROUND: Lignocellulose is considered a renewable organic material, but the industrial production of biofuel from lignocellulose is challenging because of the lack of highly active hydrolytic enzymes. The guts of herbivores contain many symbiotic microorganisms that have evolved to hydrolyze plant lignocellulose. Chinese bamboo rats mainly consume high-fiber foods, indicating that some members of the intestinal tract microbiota digest lignocellulose, providing these rats with the energy required for growth. RESULTS: Here, we used metagenomics to analyze the diversity and functions of the gut microbiota in Chinese bamboo rats. We identified abundant populations of lignocellulose-degrading bacteria, whose main functions involved carbohydrate, amino acid, and nucleic acid metabolism. We also found 587 carbohydrate-active enzyme genes belonging to different families, including 7 carbohydrate esterase families and 21 glycoside hydrolase families. The glycoside hydrolase 3, glycoside hydrolase 1, glycoside hydrolase 43, carbohydrate esterase 4, carbohydrate esterase 1, and carbohydrate esterase 3 families demonstrated outstanding performance. CONCLUSIONS: The microbes and enzymes identified in our study expand the existing arsenal of proficient degraders and enzymes for lignocellulosic biofuel production. This study also describes a powerful approach for targeting gut microbes and enzymes in numerous industries.

Research progress on the neck management of oral squamous cell carcinoma with clinically node-positive neck / 口腔疾病防治

@#Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the oral and maxillofacial regions. Cervical lymph node metastasis is not only an important biological behavior of oral cancer but also an important factor affecting the prognosis of oral cancer patients. As neck dissection is the most commonly used method of neck management, the appropriate choice of surgical procedure is very important. The current view is that radical neck dissection or modified radical neck dissection can be used for patients with clinically node-positive neck (cN+), while selective neck dissection can be used for patients with clinically node-negative neck (cN0). In recent years, selective neck dissection has been increasingly popularized and applied. Its implications are also gradually expanding from cN0 to cN+. However, there is still no consensus on whether selective neck dissection can also be used in patients with cN+ necks. This article reviews the clinical studies on the neck management of cN+ OSCC patients in recent years, analyzes the effects of different neck dissections on the prognosis of cN+ OSCC patients, and summarizes the treatment principles of neck management.

Evaluation of continuous metabolic syndrome score as a screening tool for metabolic syndrome in Xinjiang urban population aged 15-18 years / 中国学校卫生

Objective@#The purpose of the present study was to evaluate of continuous metabolic syndrome score (cMetS) in screening metabolic syndrome (MetS) and to determine the cut-off values in a representative sample of Xinjiang population aged 15 to 18 years old.@*Methods@#A stratified cluster sampling was used to select participants aged 15-18 years from 13 cities in Xinjiang. cMetS was calculated by summing up the Zscores of standardized waist circumference, mean arterial pressure, high-density lipoprotein, triglyceride, and fasting blood glucose by age and gender.@*Results@#Totally 16.3% of subjects were overweight, and 5.2% were obese. The proportion of overweight and obesity in males was significantly higher than that in females (18.1% vs 13.8%)(6.0% vs. 4.1%)(χ2=15.36，7.89，P<0.05). The prevalence of total MetS was 6.1%, with 6.6% and 5.4% for men and women, respectively. There was a correlation between cMetS and MetS components, and the average cMetS value increased with increasing MetS component(P<0.05). The total cut-off value of cMetS was 0.99 (sensitivity 68.0%, specificity 80.7%), and the area under the ROC curve was 84.9%. The cMetS scores for boys and girls were 0.80 and 1.48, respectively.@*Conclusion@#Compared with MetS, cMetS shows more accuracy in screening MetS among youth aged 15-18 years in both gender.

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 / 华中科技大学学报（医学）（英德文版）

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.

The rare intracellular RET mutation p.S891A in a Chinese Han family with familial medullary thyroid carcinoma.

We report intracellular RET mutation in a Han Chinese pedigree with familial medullary thyroid carcinoma (FMTC). Direct sequencing of RET proto-oncogene identified a missense c.2671T>G (p.S891A) mutation in 6 of 14 family members. The single nucleotide polymorphisms c. 135A>G (p.A45A), IVS4+48A>G, c. 1296A>G (p.A432A), c. 2071G>A (p.G691S), c. 2307T>G (p.L769L) and a variant c. 833C>A (p.T278N) were also found in 6 carriers. Among 5 of the 6 carriers presented medullary thyroid carcinoma (MTC) as an isolated clinical phenotype, with elevated basal serum calcitonin (Ct). Two underwent non-normative thyroidectomy either two or four times without physician awareness or diagnosis of this disease at initial treatment, but with elevated Ct. One with elevated pre-Ct accepted total thyroidectomy (TT) with modified bilateral neck dissection (MBiND), and whose seventh posterior rib MTC metastases was confirmed 5 months after surgery. Moreover, results of two affected individuals with elevated Ct were reduced to normal after TT with MBiND or prophylactic VI compartmental dissection. However, only another carrier with the variant p.T278N had slightly elevated Ct rejected surgery and was strictly monitored. Given these case results, we suggest that screening of RET and pre-surgical Ct levels in the management of MTC patients is essential for earlier diagnosis and more normative initial treatment, that FMTC patients with cervical lymph nodes metastases may be cured by TT with MBiND, and that prophylactic VI compartmental dissection should be avoided when Ct levels are low.

Atypical chronic myeloid leukaemia with trisomy 13: a case report / 中国医学科学杂志(英文版)

A typical chronic myeloid leukaemia (aCML), which shows both myeloproliferative and myelodysplastic features, is a type of myeloproliferative/myelodysplastic disease as defined by the World Health Organisation (WHO) classification of the myeloid neoplasms. Because of the presence of neutrophilic leukocytosis, aCML may resemble chronic myelogenous leukemia (CML). However, in contrast with CML, aCML does not have the Philadelphia chromosome or the bcr/abl fusion gene. With the continuous karotype analysis of aCML, several changes in the karyotype of aCML have been detected. However, few are recurring and no specific cytogenetic changes have been associated with aCML. Nonspecific cytogenetic abnormalities can be observed in 56%~82% of aCML cases. Although the most frequent abnormalities include trisomy 8 and del (20q), abnormalities involving other chromosomes such as 12, 13, 14, 17, and 19 have also been described. In this report we describe a case of aCML with trisomy 13.