Differentiation of closely-related species within Acinetobacter baumannii-calcoaceticus complex via Raman spectroscopy: a comparative machine learning analysis.

Bacterial species within the Acinetobacter baumannii-calcoaceticus (Acb) complex are very similar and are difficult to discriminate. Misidentification of these species in human infection may lead to severe consequences in clinical settings. Therefore, it is important to accurately discriminate these pathogens within the Acb complex. Raman spectroscopy is a simple method that has been widely studied for bacterial identification with high similarities. In this study, we combined surfaced-enhanced Raman spectroscopy (SERS) with a set of machine learning algorithms for identifying species within the Acb complex. According to the results, the support vector machine (SVM) model achieved the best prediction accuracy at 98.33% with a fivefold cross-validation rate of 96.73%. Taken together, this study confirms that the SERS-SVM method provides a convenient way to discriminate between A. baumannii, Acinetobacter pittii, and Acinetobacter nosocomialis in the Acb complex, which shows an application potential for species identification of Acinetobacter baumannii-calcoaceticus complex in clinical settings in near future.

Rapid discrimination of Shigella spp. and Escherichia coli via label-free surface enhanced Raman spectroscopy coupled with machine learning algorithms.

Shigella and enterotoxigenic Escherichia coli (ETEC) are major bacterial pathogens of diarrheal disease that is the second leading cause of childhood mortality globally. Currently, it is well known that Shigella spp., and E. coli are very closely related with many common characteristics. Evolutionarily speaking, Shigella spp., are positioned within the phylogenetic tree of E. coli. Therefore, discrimination of Shigella spp., from E. coli is very difficult. Many methods have been developed with the aim of differentiating the two species, which include but not limited to biochemical tests, nucleic acids amplification, and mass spectrometry, etc. However, these methods suffer from high false positive rates and complicated operation procedures, which requires the development of novel methods for accurate and rapid identification of Shigella spp., and E. coli. As a low-cost and non-invasive method, surface enhanced Raman spectroscopy (SERS) is currently under intensive study for its diagnostic potential in bacterial pathogens, which is worthy of further investigation for its application in bacterial discrimination. In this study, we focused on clinically isolated E. coli strains and Shigella species (spp.), that is, S. dysenteriae, S. boydii, S. flexneri, and S. sonnei, based on which SERS spectra were generated and characteristic peaks for Shigella spp., and E. coli were identified, revealing unique molecular components in the two bacterial groups. Further comparative analysis of machine learning algorithms showed that, the Convolutional Neural Network (CNN) achieved the best performance and robustness in bacterial discrimination capacity when compared with Random Forest (RF) and Support Vector Machine (SVM) algorithms. Taken together, this study confirmed that SERS paired with machine learning could achieve high accuracy in discriminating Shigella spp., from E. coli, which facilitated its application potential for diarrheal prevention and control in clinical settings. Graphical abstract.

Prevalence of diabetes mellitus among Uygur children in Hotan Prefecture of Xinjiang, China. / æ–°ç–†å’Œç”°åœ°åŒºç»´å¾å°”æ—å„¿ç«¥ç³–å°¿ç— æ‚£ç— çŽ‡è°ƒæŸ¥.

OBJECTIVES: To investigate the prevalence of diabetes mellitus (DM) among Uygur children in Hotan Prefecture of Xinjiang, China, as well as the factors influencing the development of DM. METHODS: The cluster random sampling method was used to select 5 308 children, aged 4-18 years, from the middle and primary schools and kindergartens in Hotan Prefecture of Xinjiang. The survey methods included questionnaire survey and the measurement of height and weight. All subjects were tested for fasting fingertip blood glucose to investigate the prevalence of DM and impaired fasting glucose (IFG). RESULTS: A total of 5 184 valid questionnaires were collected. Fourteen children (0.27%) were found to have DM, among whom 8 had type 1 DM, 2 had type 2 DM, and 4 had unclassified DM. Twenty-nine children (0.56%) were found to have IFG. There was no significant difference in the prevalence rate of DM and IFG between boys and girls (P>0.05). The prevalence rate of DM was 0.18% in the 4-<10 years group, 0.47% in the 10-<15 years group, and 0.07% in the 15-18 years group (P=0.072).The prevalence rate of IFG in the above three age groups was 0.18%, 0.94%, and 0.42%, respectively, with a significant difference among groups (P=0.007). The proportion of family history of DM and the proportion of overweight/obesity in children with DM were significantly higher than those in children without DM (P<0.05), while the proportion of children with DM who preferred coarse grains was significantly lower than that in children without DM (P<0.05). CONCLUSIONS: The prevalence of DM and IFG in Uyghur children in Hotan Prefecture of Xinjiang is relatively low. There is no significant difference in the prevalence of DM among children of different genders or age groups, but the prevalence of IFG in children of different age groups is different. A family history of DM, overweight or obesity, and low intake of coarse grains might be associated with the development of DM.

Paclitaxel induces apoptosis through the TAK1-JNK activation pathway.

Paclitaxel (PTX) has previously been used to treat tumours of various tissue origins, such as lung, breast, ovarian, prostate cancers and leukemia. PTX-induced apoptosis is associated with p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), nuclear factor-kappa B (NF-κB) and c-Jun N-terminal kinase or stress-activated protein kinase (JNK/ SAPK) pathways. Transforming growth factor-beta-activated kinase 1 (TAK1) and TAK1-binding protein 1 (TAB1) play an important role in cell apoptosis through the p38, ERK, NF-κB and JNK signal transduction pathways. To investigate the role of TAK1 in PTX-induced cell apoptosis, we treated HEK293 and 8305C cells with 0-20 µM PTX for 6, 12 or 24 h. To investigate whether TAK1 can cooperate with PTX for cancer treatment, we transfected cells with TAK1, TAB1 or control plasmid and treated them with PTX (3-10 µM) for 9-24 h. Apoptosis rates were analysed by flow cytometry (Annexin V/PI). Endogenous TAK1 and TAB1, caspase-7 cleavage, poly ADP-ribose polymerase (PARP) cleavage, Bcl-xL level, phospho-p44/42, phospho-JNK and phospho-p38 were detected by western blot. We show that in HEK293 and 8305C cells, PTX enhanced the endogenous TAK1/TAB1 level and induced cell apoptosis in a dose- and time-dependent manner. Upon TAK1 overexpression in HEK293 cells treated with PTX, apoptosis rate, JNK phosphorylation and PARP cleavage increased contrary to heat-shocked or untreated cells. CRISPR editing of the tak1 gene upon PTX treatment resulted in lower phospho-JNK and PARP cleavage levels than in cells transfected with the control or the TAK1- or TAB1 + TAK1-containing plasmids. TAK1-K63A could not induce JNK phosphorylation or PARP cleavage. We conclude that PTX induces HEK293 and 8305C cell apoptosis through the TAK1-JNK activation pathway, potentially highlighting TAK1's role in chemosensitivity.

A Novel Homozygous Truncating Mutation in LAMB2 Gene in a Chinese Uyghur Patient With Severe Phenotype Pierson Syndrome.

Objective: Pierson syndrome (OMIM 609049) is a rare autosomal recessive disorder characterized by congenital nephrotic syndrome and complex ocular abnormalities. Severe renal symptoms had be associated with truncating mutations. Few Chinese patients from diverse ethnic background had been evaluated and reported with this syndrome. Here we report the first Uyghur patient with typical Pierson syndrome phenotypes and a novel pathogenic homozygous variant in LAMB2 gene. Method: A thirty-nine-day old Uyghur girl was born to consanguineous parents, the girl presented with general edema, severe hypotonia and bilateral microcoria. Laboratory tests revealed severe proteinuria, microscopic haematuria, hypoalbuminaemia. By the age of 74 days, she died of renal failure and respiratory infection. We detected on mutations of LAMB2 gene by the sanger sequencing. Result:Sanger sequencing detected a homozygous 2-bp deletion (c.2044_2045insTT/p.Cys682Phefs*13) in the exon 16 of LAMB2 gene. Both parents are heterozygous carriers. Conclusion: We reported the first Uyghur case of LAMB2 gene homozygous mutation leading to severe phenotype Pierson syndrome. The clinical presentation of the patient and the novel pathogenic variant detected in this patient added to the overall knowledge of this rare condition.

Production of chlorothalonil hydrolytic dehalogenase from agro-industrial wastewater and its application in raw food cleaning.

BACKGROUND: To reduce the fermentation cost for industrialization of chlorothalonil hydrolytic dehalogenase (Chd), agro-industrial wastewaters including molasses, corn steep liquor (CSL) and fermentation wastewater were used to substitute for expensive carbon and nitrogen sources and fresh water for lab preparation. RESULTS: The results showed that molasses and CSL could replace 5% carbon source and 100% organic nitrogen source respectively to maintain the same fermentation level. Re-fermentation from raffinate of ultra-filtered fermentation wastewater could achieve 61.03% of initial Chd activity and reach 96.39% activity when cultured in a mixture of raffinate and 50% of original medium constituent. Typical raw foods were chosen to evaluate the chlorothalonil removal ability of Chd. After Chd treatment for 2 h at room temperature, 97.40 and 75.55% of 30 mg kg-1 chlorothalonil on cherry tomato and strawberry respectively and 60.29% of 50 mg kg-1 chlorothalonil on Chinese cabbage were removed. Furthermore, the residual activity of the enzyme remained at 78-82% after treatment, suggesting its potential for reuse. CONCLUSION: This study proved the cost-feasibility of large-scale production of Chd from agro-industrial wastewater and demonstrated the potential of Chd in raw food cleaning. © 2016 Society of Chemical Industry.

ON THE DISTRIBUTION OF THE GREATEST COMMON DIVISOR OF GAUSSIAN INTEGERS.

For a pair of random Gaussian integers chosen uniformly and independently from the set of Gaussian integers of norm x or less as x goes to infinity, we find asymptotics for the average norm of their greatest common divisor, with explicit error terms. We also present results for higher moments along with computational data which support the results for the second, third, fourth, and fifth moments. The analogous question for integers is studied by Diaconis and Erdös.

[Genotypes and phenotypes in Uygur children with 21-hydroxylase deficiency in Xinjiang, China].

OBJECTIVE: To investigate gene mutations and the relationship between genotypes and clinical phenotypes in Uygur children with 21-hydroxylase deficiency (21-OHD) in Xinjiang, China. METHODS: A total of 20 Uygur children with 21-OHD who visited the hospital between October 2013 and October 2014 were enrolled. Full-length direct sequencing and multiplex ligation-dependent probe amplification (MLPA) were used to detect the mutations of CYP21A2 gene, which encoded 21-hydroxylase. According to the type of mutation, the patients with 21-OHD were divided into different groups to analyze the consistency between predicted clinical phenotypes and actual clinical phenotypes. RESULTS: A total of 9 mutation types were found in the 20 patients, and 8 of them were identified as pathogenic mutations, i.e., Del, conv, I2g, I172N, Cluster E6, 8-bp del, V281L, and R356W. The other mutation is the new mutation occurring in intron 5 (c.648+37A>G), which had not been reported, and its pathological significance remains unknown. Most clinical phenotypes predicted by mutation types had a higher coincidence rate with actual clinical phenotypes (above 67%), and the clinical phenotypes predicted by P30L and V281L had a lower coincidence rate with actual clinical phenotypes (below 33%). CONCLUSIONS: The genotype of 21-OHD has a good correlation with phenotype, and the clinical phenotype can be predicted by detecting the patient′s genotype. The new mutation (c.648+37A>G) may be related to the pathogenesis of 21-OHD.

[Prenatal diagnosis of ß-thalassaemia using cell-free fetal DNA in maternal plasma].

OBJECTIVE: To investigate the clinical feasibility of cell-free fetal DNA (cffDNA)-based noninvasive prenatal diagnosis of ß-thalassemia. METHODS: Nine samples of amniotic fluid were obtained to detect the 8 common and 9 relatively rare mutation sites of ß-thalassaemia in Guangdong Province. The maternal blood samples were also collected for extracting and purification of the cffDNA, and a duplex PCR was performed using 3 pairs of primers and the fetal ß-globin genotype was analyzed by reverse dot-blot hybridization. RESULTS: Among the 9 cases, 5 showed fetal genotypes of ß-thalassemia inherited from the father by examination of the amniotic fluid, and 2 fetuses were identified to have ß-thalassemia genes inherited from the father determined based on the cffDNA in the maternal blood. CONCLUSIONS: The cffDNA-based noninvasive prenatal diagnosis is feasible for ß-thalassemia, but the contamination of the maternal background DNA results in a low detection rate.

Thyrotropin receptor and thyroid transcription factor-1 genes variant in Chinese children with congenital hypothyroidism.

The aim of the present study was to investigate the mutation/variant of thyrotropin receptor (TSHR) and thyroid transcription factor-1 (TTF-1) genes in Chinese children with congenital hypothyroidism (CH). Seventy-nine and forty-nine Chinese children with CH were enrolled for molecular analysis of the TSHR gene and TTF-1 gene, respectively. One hundred normal children were evaluated as control. The coding regions of TSHR and TTF-1 genes were amplified by polymerase chain reaction and sequenced. Sequencing of the TSHR gene revealed a compound heterozygous variants (Pro52Thr/Val689Gly) and a heterozygous variant (Gly245Ser) in 2 of 79 patients. In 30 patients and 33 controls the normal cytosine at position 2181 in exon 10 of TSHR gene was replaced by a guanineCresulting in the replacement of Asp (727) by Glu. In 47 patients and 50 controls, the normal thymidine at position 561 in exon 7 of TSHR gene was replaced by a cytosine. This substitution did not change the amino acid in position 187. Sequencing of the TTF-1 gene revealed no mutation or polymorphism in 49 patients and 100 controls. In conclusion, three heterozygous variants (Pro52Thr, Gly245Ser, Val689Gly) of TSHR gene were firstly detected in Chinese children with CH. There were polymorphisms in exon 10 at nucleotide 2181 (C/G) and in exon 7 at nucleotide 561 (T/C) in TSHR gene. No mutation or polymorphism was detected in the coding region of TTF-1 gene. The mutation/variant of TSHR and TTF-1 genes is relatively rare in Chinese children with CH.

[Thyrotropin receptor gene inactivating mutation in Chinese children with congenital hypothyroidism].

OBJECTIVE: The inactivating mutation of thyrotropin receptor (TSHR) gene results in partial or complete insensitivity of thyrotropin (TSH) and dysfunction of the TSH-TSHR-cAMP cascade. Therefore, it may cause congenital hypothyroidism (CH). Depending on the degree of impairment of TSHR function, patients can present with subclinical hypothyroidism at one extreme of the spectrum, or severe hypothyroidism at the other. This study aimed to understand the relation between inactivating mutations of TSHR gene and Chinese children with CH. METHODS: (1) Seventy-nine Chinese children with CH, including 14 subclinical hypothyroidism patients (8 boys and 6 girls, age 1 - 5.5 years) and 65 hypothyroidism patients (27 boys and 38 girls, age 1.5 - 6 years) were enrolled in this study. Meanwhile, 100 normal children were enrolled as control, 40 were male and 60 were female. The age of the normal children were at a range of 1 - 8 years. (2) Total genomic DNA was extracted from peripheral blood leukocytes of the 79 patients and 100 normal subjects. Exons 1 - 10 of TSHR gene were individually amplified by polymerase chain reaction (PCR) and mutations were detected by direct sequencing. RESULTS: (1) A compound heterozygous missense mutations (Pro52Thr/Val689Gly) and a heterozygous missense mutation (Gly245Ser) were detected in 79 patients. The mutations of Pro52Thr and Gly245Ser were located within the extracellular domain of TSHR, while Val689Gly was located within the intracellular domain of TSHR. In 30 patients the normal cytosine at position 2181 in exon 10 was replaced by a guanine (GAC-->GAG), resulting in the replacement of Glu(727) by Asp. In 47 patients, the normal thymidine at position 561 in exon 7 was replaced by a cytosine (AAT-->AAC). This substitution did not change the amino acid (Asn) at position 187. (2) In 33 normal children the normal cytosine at position 2181 in exon 10 was also replaced by a guanine (GAC-->GAG) and in 50 normal children the normal thymidine at position 561 in exon 7 was replaced by a cytosine (AAT-->AAC). CONCLUSIONS: Three heterozygous missense mutations (Pro52Thr, Gly245Ser, Val689Gly) of TSHR gene were firstly detected in Chinese children with CH. There was a polymorphism in exon 10 at nucleotide 2181 (GAC-->GAG) and in exon 7 at nucleotide 561 (AAT-->AAC) in TSHR gene. The inactivating mutation of TSHR gene is an infrequent pathogeny for CH.

[Follow-up study of mental developments in high-risk children].

OBJECTIVE: To study the mental developments in high risk children and the impact of the high risk factors on neurologic abnormalities, mental defect and long-term outcome. METHODS: The mental development of 122 children who had been exposed to high-risk factors and treated between March 1994 to May 1995 during their newborn periods was evaluated. Gesell development scales were performed when they were at 6 and 12 months old. And Wechsler intelligence scales for children (Chinese version) were performed at 6 approximately 7 years old. RESULTS: The children exposed to hypoglycemia during their newborn period and preterm labor had significantly lower IQ, VIQ and PIQ scores (P <0.05). The other risk factors in order were low birth weight, severe anoxia, asphyxia at birth, erythrocythemia, hyperbilirubinemia. There was significant difference between the children exposed to one risk factor and those exposed to two or more risk factors (P <0.05). And there was significant correlation between developmental assessment at 6 and 12 months and mental development at 6 approximately 7 years old (P<0.01). CONCLUSION: The impact of the high risk factors at birth on children's mental development is not negligible. And the risk of development abnormalities will increase if the children were exposed to multiple risk factors. The evaluation of development at 6 approximately 12 months is of predictive value for long-term outcome.