A Cadaveric Limb Analysis of the Posterior Tibial Musculotendinous Junction to determine the feasibility of Interosseous Membrane Tendon Transfer.

The transfer of the posterior tibial tendon through the interosseous membrane is potentially an effective treatment to correct the deformity of the foot and ankle. Our study aimed to evaluate the anatomical feasibility of anterior transfer of the posterior tibial tendon through the interosseous membrane route using the musculotendinous junction (MTJ). Eighteen adult cadavers were used. The width and thickness of the tibial posterior MTJ, width of the interosseous membrane at the corresponding level, and the window size of the interosseous membrane were measured. Additionally, the distance between the distal end of the MTJ and the tip of the medial malleolus were recorded. The mean length of the posterior tibial tendon was 83.60 mm, the mean distance of the posterior tibial MTJ to medial malleolus tip was 45.48 mm and the mean length of MTJ was 31.74 mm. The mean width of distal end of MTJ was 7.76 mm, thickness of distal end of MTJ was 4.07 mm and the mean width of the interosseous membrane at the distal end of MTJ was 4.76 mm. We found the mean width of the proximal end of MTJ was 20.68 mm, the mean thickness of proximal end of MTJ was 5.52 mm, and mean width of interosseous membrane at the proximal end of MTJ was 8.76 mm. Our study has demonstrated that a 31 mm length incision made at approximately 45 mm from the proximal end of the medial malleolus can safely reach the MTJ. We recommend an opening length of the interosseous membrane of at least 20 mm.

Identification, characterization and expression profiles of PSEN2 in the Chinese tree shrew (Tupaia belangeri chinensis).

The gene PSEN2 encodes presenilin-2, a subunit of γ-secretase. Mutations in PSEN2 are not only related to Alzheimer's disease but are also involved in other diseases. The Chinese tree shrew (Tupaia belangeri chinensis) is a potential animal model for Alzheimer's disease, although little is known about its cDNA sequence, protein structure, and PSEN2 expression. To better understand PSEN2 in the tree shrew, we cloned this gene by rapid amplification of cDNA ends technology. Hence, we analyzed the sequence and molecular characteristics of PSEN2 mRNA, predicted its spatial structure, and analyzed its expression profiles. We found that tree shrew PSEN2 is 1539 base pairs in length and encodes 330 amino acids. It is homologous and genetically similar to humans (97.64% identity). The protein structure of tree shrew PSEN2 indicated similarities to human PSEN2, both being comprised of numerous transmembrane helices. However, tree shrew PSEN2 possesses seven α-helices, and thus lacks three compared with human PSEN2. Tree shrew PSEN2 mRNAs were ubiquitously detected in all tissues, with a tissue- and temporal-specific pattern. These results pave the way towards the function of tree shrew PSEN2, which will give insights into the mechanisms leading to neurodegenerative and other diseases in humans.

A Novel MEF2C Loss-of-Function Mutation Associated with Congenital Double Outlet Right Ventricle.

Congenital heart defect (CHD) represents the most prevalent birth defect, and accounts for substantial morbidity and mortality in humans. Aggregating evidence demonstrates the genetic basis for CHD. However, CHD is a heterogeneous disease, and the genetic determinants underlying CHD in most patients remain unknown. In the present study, a cohort of 186 unrelated cases with CHD and 300 unrelated control individuals were recruited. The coding exons and flanking introns of the MEF2C gene, which encodes a transcription factor crucial for proper cardiovascular development, were sequenced in all study participants. The functional effect of an identified MEF2C mutation was characterized using a dual-luciferase reporter assay system. As a result, a novel heterozygous MEF2C mutation, p.R15C, was detected in an index patient with congenital double outlet right ventricle (DORV) as well as ventricular septal defect. Analysis of the proband's pedigree showed that the mutation co-segregated with CHD with complete penetrance. The missense mutation, which changed the evolutionarily conserved amino acid, was absent in 300 control individuals. Functional deciphers revealed that the mutant MEF2C protein had a significantly decreased transcriptional activity. Furthermore, the mutation significantly reduced the synergistic activation between MEF2C and GATA4, another transcription factor linked to CHD. This study firstly associates MEF2C loss-of-function mutation with DORV in humans, which provides novel insight into the molecular pathogenesis of CHD, suggesting potential implications for genetic counseling and personalized treatment of CHD patients.

A new nomogram score for predicting surgery-related pressure ulcers in cardiovascular surgical patients.

The aim of this study was to build a new nomogram score for predicting surgery-related pressure ulcers (SRPU) in cardiovascular surgical patients. We performed a prospective cohort study among consecutive patients with cardiovascular surgery between January 2015 and December 2015. Univariate and multivariate logistic regression was used to analyse the risk factors for SRPU. A nomogram-predicting model was built based on the logistic regression model. Then, calibration and discrimination were tested. A total of 149 patients with cardiovascular surgery were included in the study. Thirty-seven patients developed SRPUs, with an incidence rate of 24·8% (95%CI: 18·1-32·6%). The logistic regression model for predicting SRPU with four risk factors was Logit(P) = (1·861 × VDH, OR 2·174 × CAD, OR 1·747 × TAA) - 0·029 × weight + 0·005 × surgery duration + 1·241 × perioperative corticosteroids administration (P = 0·003, R2 = 0·1181). The goodness-of-fit test (Pearson χ2 = 150·69, P = 0·217) indicated acceptable calibration, and the C-index (0·725) indicated moderate discrimination. When the probability cut-off is 0·25 (total score 12), the nomogram model has the best sensitivity and specificity in predicting SRPU. We established a new nomogram model that can provide an individual prediction of SRPU in cardiovascular surgical patients. When the probability is more than 0·25 (total score 12), the cardiovascular surgery patients should be considered at high-risk.

Risk factors analysis and prediction model construction for severe pneumonia in older adult patients.

Objective: Pneumonia is a common and serious infectious disease that affects the older adult population. Severe pneumonia can lead to high mortality and morbidity in this group. Therefore, it is important to identify the risk factors and develop a prediction model for severe pneumonia in older adult patients. Method: In this study, we collected data from 1,000 older adult patients who were diagnosed with pneumonia and admitted to the intensive care unit (ICU) in a tertiary hospital. We used logistic regression and machine learning methods to analyze the risk factors and construct a prediction model for severe pneumonia in older adult patients. We evaluated the performance of the model using accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), and calibration plot. Result: We found that age, comorbidities, vital signs, laboratory tests, and radiological findings were associated with severe pneumonia in older adult patients. The prediction model had an accuracy of 0.85, a sensitivity of 0.80, a specificity of 0.88, and an AUC of 0.90. The calibration plot showed good agreement between the predicted and observed probabilities of severe pneumonia. Conclusion: The prediction model can help clinicians to stratify the risk of severe pneumonia in older adult patients and provide timely and appropriate interventions.

CTHRC1 promotes growth, migration and invasion of trophoblasts via reciprocal Wnt/ß-catenin regulation.

Preeclampsia (PE) is a pregnancy complication that is characterized by high blood pressure and is associated with high maternal and fetal morbidities. At a mechanistic level, PE is characterized by reduced invasion ability of trophoblasts. Collagen triple helix repeat containing-1 (CTHRC1) is a well-known tumor-promoting factor in several malignant tumors, but its role in trophoblasts remains unknown. In this study, we characterized the expression of CTHRC1 in placenta tissue samples from PE pregnancies and from normal pregnancies. We used the trophoblasts cell lines HTR-8/SVneo and JEG-3 to investigate the role of CTHRC1 in cell migration, invasion and proliferation. Western blot, PCR and TOP/FOP luciferase activity assays were used to investigate the molecular mechanisms underlying these cell behaviors. Placenta tissue samples obtained from pregnant women with PE expressed lower levels of CTHRC1 than those of placenta tissues from women with normal pregnancies. Down-regulation of CTHRC1 impaired cell proliferation, migration and invasion of trophoblasts, while CTHRC1 overexpression promoted nuclear translocation of ß-catenin, a result that was further confirmed by TOP/FOP luciferase activity assay. Our findings suggest that CTHRC1 promotes migration and invasion of trophoblasts via reciprocal Wnt/ß-catenin signaling pathway. Down-regulation of CTHRC1 may be a potential mechanism underpinning the development of preeclampsia.

Slack and Slick KNa channels are required for the depolarizing afterpotential of acutely isolated, medium diameter rat dorsal root ganglion neurons.

AIM: Na+-activated K+ (K(Na)) channels set and stabilize resting membrane potential in rat small dorsal root ganglion (DRG) neurons. However, whether K(Na) channels play the same role in other size DRG neurons is still elusive. The aim of this study is to identify the existence and potential physiological functions of K(Na) channels in medium diameter (25-35 microm) DRG neurons. METHODS: Inside-out and whole-cell patch-clamp were used to study the electrophysiological characterizations of native K(Na) channels. RT-PCR was used to identify the existence of Slack and Slick genes. RESULTS: We report that K(Na) channels are required for depolarizing afterpotential (DAP) in medium sized rat DRG neurons. In inside-out patches, K(Na) channels represented 201 pS unitary chord conductance and were activated by cytoplasmic Na+ [the half maximal effective concentration (EC50): 35 mmol/L] in 160 mmol/L symmetrical K+o/K+i solution. Additionally, these K(Na) channels also represented cytoplasmic Cl(-)-dependent activation. RT-PCR confirmed the existence of Slack and Slick genes in DRG neurons. Tetrodotoxin (TTX, 100 nmol/L) completely blocked the DRG inward Na+ currents, and the following outward currents which were thought to be K(Na) currents. The DAP was increased when extracellular Na+ was replaced by Li+. CONCLUSION: We conclude that Slack and Slick K(Na) channels are required for DAP of medium diameter rat DRG neurons that regulate DRG action potential repolarization.

A novel HAND2 loss-of-function mutation responsible for tetralogy of Fallot.

Congenital heart disease (CHD), the most common type of developmental abnormality, is associated with substantial morbidity and mortality in humans worldwide. The basic helix-loop-helix transcription factor, heart and neural crest derivatives expressed 2 (HAND2), has been demonstrated to be crucial for normal cardiovascular development in animal models. However, whether a genetically defective HAND2 contributes to congenital heart disease (CHD) in humans remains to be explored. In this study, the entire coding region and splicing boundaries of the HAND2 gene were sequenced in a cohort of 145 unrelated patients with CHD. A total of 200 unrelated, ethnically-matched healthy individuals used as controls were also genotyped for HAND2. The functional effect of the mutant HAND2 was characterized in contrast to its wild-type counterpart by using a dual-luciferase reporter assay system. As a result, a novel heterozygous HAND2 mutation, p.L47P, was identified in a patient with tetralogy of Fallot (TOF). The misense mutation, which altered the amino acid conserved evolutionarily among species, was absent in 400 control chromosomes. Functional analyses unveiled that the mutant HAND2 had a significantly decreased transcriptional activity. Furthermore, the mutation markedly reduced the synergistic activation between HAND2 and GATA4 or NKX2.5, other two cardiac key transcription factors involved in the pathogenesis of CHD. To the best of our knowledge, this study is the first to report the association of a HAND2 loss-of-function mutation with an increased vulnerability to TOF in humans, which provides novel insight into the molecular mechanism underpinning CHD, suggesting potential implications for the genetic counseling of families with CHD.

DNA sequencing of a plasmid with virulence from marine fish pathogen Vibrio anguillarum.

DNA sequence of a plasmid pEIB1 associated with virulence from the marine fish pathogen Vibrio anguillarum was determined using the methods of restriction endonuclease digestion, subcloning, and primer walking. The whole length of obtained pEIB1 DNA sequence was 66 164 bp, and the overall G+C content of DNA sequence is 42.7%. This sequence encodes 44 open reading frames containing the genes of DNA replication, biosynthesis and regulation of the siderophore anguibactin and transport of ferric-anguibactin complexes.

FOXP3 demethylation as a means of identifying quantitative defects in regulatory T cells in acute coronary syndrome.

OBJECTIVE: The contribution of regulatory T cells (Tregs) to the pathogenesis of acute coronary syndrome (ACS) remains poorly understood. One core obstacle is the lack of Treg-specific markers. A highly conserved CpG enriched element in forkhead box P3 intron 1 (FOXP3 i l) is unmethylated only in Tregs, and measuring the unmethylation of FOXP3 i l can be used to identify the role of Tregs in clinical diseases. This study investigated whether analyzing the demethylation status of FOXP3 i 1 is a more reliable means than using Treg-specific surface markers in ACS. METHODS AND RESULTS: We evaluated circulating Tregs percentages on different levels including cell frequencies (CD4(+)CD25(hi)FOXP3(+)Tregs and CD4(+)CD25(hi)CD45(+)naïve Tregs) or FOXP3 mRNA, FOXP3 i 1 demethylation status and related cytokine secretion in 89 patients with ACS and 35 controls. FOXP3 i 1 demethylation assay showed that the amount of Tregs in ACS patients was significantly reduced than that in controls (p = 0.0005). However, flow cytometry analysis did not identify any reduction of CD4(+)CD25(hi)FOXP3(+)Tregs in ACS patients. Notably, younger patients had higher percentage of CD4(+)CD25(hi)FOXP3(+)Tregs but decreased percentage of CD4(+)CD25(hi)CD45(+)naïve Tregs than either controls or older patients. Furthermore, a DNA hypomethylation agent increased the amount of CD4(+)CD25(hi)FOXP3(+)Tregs and Tregs related cytokine IL-10 and suppressed the production of pro-inflammatory cytokine interferon-γ by inducing FOXP3 i 1 demethylation in vitro. CONCLUSIONS: A quantitative defect of Tregs, suggestive of decreased peripheral tolerance, could be a potential hallmark of ACS disease. Targeting FOXP3 i l demethylation might elevate the inhibitory activity of Tregs in ACS.

[Cloning of full-length coding sequence of tree shrew CD3E and prediction of its molecular characteristics].

The use of tree shrews (Tupaia belangeri) in human disease studies demands essential research tools, in particular cellular markers and their monoclonal antibodies for immunological studies. Here we cloned the full-length cDNAs encoding CD3E from total RNA of the spleen, liver and peripheral blood of tree shrews and analyzed their structural characteristics in comparison with other mammals by Discovery Studio software. The results showed that the open reading frame sequence of tree shrew CD3E was 582 bp, encoding 194 amino acids. The overall structure of tree shrew CD3E protein was similar to its counterparts of other mammals, intracellular and transmembrane domain highly conserved. However, detailed analysis revealed two potential glycosylation sites and different surface charges in the extracellular domain. Availability of the entire open-reading-frame and related sequence information would therefore facilitate the preparation of monoclonal antibodies against tree shrew CD3 and further studies for its function.

[Characteristics of nitrite accumulation in a hydrogenotrophic denitrification system].

A mathematic model for nitrite accumulation in a hydrogenotrophic denitrification system running in a sequencing batch mode was developed and denitrification coefficient alpha was defined to describe the process of nitrite accumulation. The reduction rates of nitrate and nitrite and the nitrite accumulation before/after the nitrite addition were investigated using a sequencing batch reactor. The result showed that in Run 1 the reduction rates of nitrate and nitrite were 6.52 mg/(L x h) and 4.40 mg/(L x h) respectively, accompanied with the remarkable nitrite accumulation. The reduction rate of nitrite increased to 4.89 mg/(L x h) after nitrite addition. In Run 2, the reduction rate of nitrate decreased to 3.94 mg/(L x h) and almost no nitrite accumulation was observed. The addition of nitrite changed both the reduction rates of nitrate and nitrite, and finally showed an effect on the accumulated concentration of nitrite. The process of nitrite accumulation was identical with the theoretical one calculated according to the model. The nitrite accumulation could be exactly reflected by the defined denitrification coefficient alpha. When alpha was less than 1, nitrite accumulation was observed obviously with the maximum concentration 11.06 mg/L. While when alpha was more than 1, accumulated nitrite concentration was lower than 0.30 mg/L.

[Hydrogenotrophic denitrification for the removal of nitrate in drinking water].

Autotrophic denitrification with hydrogen as the electron donor for the removal of nitrate in drinking water was investigated by using a bench-scale sequencing batch reactor in an attached growth system. Gas permeable membrane was employed as the hydrogen diffuser to improve the hydrogen mass transfer and decrease the explosion risk. The results showed that nitrate could be removed efficiently with this technology. The removal rates of NO3(-)-N and TN could achieve 6.45 mg/(L h) and 4.89 mg/(L h) respectively, with the highest accumulation of NO2(-)-N 11.58 mg/L. pH increased to 10.56 and DOC increased 0.91 mg/L. A zero order kinetic model was proposed for NO3(-) and NO2(-) reduction, with the kinetic coefficients in the ranges of 0.33 - 0.60 g/(g d) and 0.37 - 0.45 g/(g d) respectively, The removal rates of NO3(-)-N and TN were not affected with the hydrogen pressure higher than 40 kPa, with the values (5.97 +/- 0.08) mg/(L h) and (4.25 +/- 0.04) mg/(L h) respectively, while decreased remarkably when the hydrogen pressure was 25 kPa. The denitrification reaction was inhibited at pH 6 with the removal rate of NO3(-)-N 1.83 mg/( L h); pH higher than 8 was the favorable condition for denitrification with the removal rate of NO3(-)-N 3.13 mg/(L h).