Construction of stable membranal CMTM6-PD-L1 full-length complex to evaluate the PD-1/PD-L1-CMTM6 interaction and develop anti-tumor anti-CMTM6 nanobody

CKLF (chemokine-like factor)-MARVEL transmembrane domain containing protein 6 (CMTM6) is a novel regulator to maintain the stability of PD-L1. CMTM6 can colocalize and interact with PD-L1 on the recycling endosomes and cell membrane, preventing PD-L1 from lysosome-mediated degradation and proteasome-mediated degradation thus increasing the half-life of PD-L1 on the cell membrane. The difficulties in obtaining stable full-length PD-L1 and CMTM6 proteins hinder the research on their structures, function as well as related drug development. Using lauryl maltose neopentyl glycol (LMNG) as the optimized detergent and a cell membrane mimetic strategy, we assembled a stable membrane-bound full-length CMTM6-PD-L1 complex with amphipol A8-35. When the PD-1/PD-L1-CMTM6 interactions were analyzed, we found that CMTM6 greatly enhanced the binding and delayed the dissociation of PD-1/PD-L1, thus affecting immunosuppressive signaling and anti-apoptotic signaling. We then used the CMTM6-PD-L1 complex as immunogens to generate immune repertoires in camels, and identified a functional anti-CMTM6 nanobody, called 1A5. We demonstrated that the anti-CMTM6 nanobody greatly decreased T-cell immunosuppression and promoted apoptotic susceptibility of tumor cells in vitro, and mainly relied on the cytotoxic effect of CD8+ T-cells to exert tumor growth inhibitory effects in CT26 tumor-bearing mice. In conclusion, the stable membrane-bound full-length CMTM6-PD-L1 complex has been successfully used in studying PD-1/PD-L1-CMTM6 interactions and CMTM6-targeting drug development, suggesting CMTM6 as a novel tumor immunotherapy target.

[Progress of researches on Fasciola and fascioliasis in Yunnan Province]

Fascioliasis is a zoonotic parasitic disease that seriously endangers human health and hinders socioeconomic development. Fasciola mainly infects ruminants, such as cattle and sheep. However, there has recently been a rise in the number of human cases with fascioliasis with the improvements of diagnostic techniques. During the past decades, sporadic cases of fascioliasis were predominantly identified; however, there were outbreaks of fascioliasis in Yunnan Province, which has been paid much attention. The review summarizes the advances in the distribution of Fasciola species and the progress of researches on fascioliasis in Yunnan Province.

[Investigation on Demodex infections among university students in Kunming City]

OBJECTIVE

To investigate the prevalence of Demodex infection among students in Kunming Medical University, and identify the factors affecting Demodex infections, so as to provide the evidence for the development of the strategy for the prevention of Demodex infections.

METHODS

A total of 1 463 students from Grade 2014 who studied Medical Parasitology in Kunming Medical University were included in the survey. Demodex was examined in students'facial skin using the cellophane tape method, and the species was identified using microscopy. The students'gender, ethnicity, place of origin and skin type were captured using a questionnaire survey.

RESULTS

The overall prevalence of Demodex infections was 19.07% (279/1 463) on the facial skin among the university students, and a higher prevalence was seen in girls (21.16%, 183/865) than in boys (16.05%, 96/598) (χ² =5.965,P <0.05).TheprevalenceofDemodex infectionswas18.33%(66/360)amongminorethnicstudents,andnoethnicity-specific prevalence was seen (P > 0.05). Demodex folliculorum was the predominant species, with a prevalence of 50.54% (141/279), and mild infections were predominant among all infections (96.77%, 270/279), without severe infections seen. Multivariate nonconditional logistic regression analysis revealed that gender and roommates with Demodex infections were risk factors of Demodex infections, and the infection was not associated with ethnicity, place of origin or skin type. There were only 2.53% (37/1 463) of the subjects understanding the knowledge pertaining to the prevention and control of Demodex infection.

CONCLUSIONS

A relatively low prevalence of Demodex infection is detected in the facial skin of students from Kunming Medical University, and Demodex infection is associated with gender and roommates with Demodex infections. Health education pertaining to the prevention of Demodex infections is suggested to be intensified among university students.

Overexpressed VEPH1 inhibits epithelial-mesenchymal transition, invasion, and migration of human cutaneous melanoma cells through inactivating the TGF-β signaling pathway

Malignant melanoma has a profound influence on populations around the world, with the underlying mechanisms controlling this disease yet to be fully identified. Hence, the current study aimed to investigate effects associated with VEPH1 on epithelial-mesenchymal transition (EMT), proliferation, invasion, migration and the apoptosis of human cutaneous melanoma (CM) cells through the TGF-β signaling pathway. Microarray-based gene analysis was initially performed to screen the CM-related differentially expressed genes. The expression of VEPH1, TGF-β signaling pathway- and EMT-related genes in CM tissues and cell lines was subsequently evaluated. Gain-of- and loss-of-function experiments were conducted to examine the effects of VEPH1 and the TGF-β signaling pathway on the expression of EMT-related genes, cell proliferation, migration, invasion, cell cycle and apoptosis in vitro. Finally, tumor formation in nude mice was conducted. VEPH1 was lowly expressed and regulated the progression of CM with involvement in the TGF-β signaling pathway. Human CM tissues were noted to activate the TGF-β signaling pathway and EMT. A375 cells treated with overexpressed VEPH1 plasmids or/and TGF-β signaling pathway inhibitor SB-431542 displayed diminished TGF-β, SMAD4, Vimentin and N-cadherin expression while the expression of E-cadherin was elevated, accompanied by decreased cell proliferation, migration, invasion, inhibited cell cycle entry. However, si-VEPH1 or TGF-β signaling pathway activator contributed to reverse results. Taken together, the key findings of the current study present evidence suggesting that VEPH1 protects against human CM by inhibiting the activation of the TGF-β signaling pathway, highlighting its potential as a target for the prognosis and diagnosis of CM.

Genome sequence compression based on optimized context weighting

Context weighting is an important technology for genome compression. In this study, we discuss the relationship between the weighting of context models and the weighting of the description lengths corresponding to their respective context models. It indicates that weighting of context models is equivalent to the weighting of their description lengths. With these discussions, we present the weights optimization algorithm based on the minimum description length, and suggest implementing the least-square algorithm for the optimization of the weights. The proposed optimization algorithm is used in the compression of bacterial genome sequences. The experiment results indicate that by using the proposed weights optimization method, our context weighting-based genome compression algorithm can achieve better performance than context weighting-based algorithms reported in the literature.

Prevalence and associated factors of induced abortion among rural married women: a cross-sectional survey in Anhui, China

AIM

This study aims to assess the prevalence of and factors associated with induced abortion among married women in rural areas of Anhui Province, China.

MATERIAL AND METHODS

A multistage probability sampling method was used to identify a representative sample of 53,652 married women aged 18-49 years in rural areas of Anhui Province, China. All women were interviewed in the form of a standardized questionnaire.

RESULTS

We found that 32.0% (16,800) of these women had had at least one induced abortion: 21.1% (11,090) of women had had one; 7.6% (3976) of women had had two; and 4.1% (1734) of women had had at least three. The number of induced abortions per 100 pregnancies was found to be 22.0. Multivariate analysis showed that education, the age of a woman at her first marriage, number of total births, number of total pregnancies, and contraceptive methods were significant predictors for induced abortion after controlling for women's current age, employment and family yearly income.

CONCLUSION

The study shows that the prevalence of induced abortion is still very high among married women in rural China, and highly effective methods of contraception (sterilization, intrauterine device) decrease women's recourse to induced abortion.

A systematic review and quantitative assessment of sleep-disordered breathing during pregnancy and perinatal outcomes

PURPOSE

Previous investigations have suggested a strong association between sleep-disordered breathing (SDB) during pregnancy and perinatal outcomes. However, the results of the following replication studies were not always concordant. Therefore, this meta-analysis was conducted to evaluate the more reliable estimate.

METHODS

A systematic literature search was performed on PubMed, Springer Link, and EMBASE to identify all eligible studies published before August 2013. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed or random effects model.

RESULTS

A total of 24 publications met the inclusion criteria and were included in this meta-analysis. Findings demonstrated that moderate-to-severe SDB during pregnancy was associated with gestational diabetes mellitus (OR=1.78; 95% CI, 1.29 to 2.46), pregnancy-related hypertension (OR=2.38; 95% CI, 1.63 to 3.47), preeclampsia (OR=2.19; 95% CI, 1.71 to 2.80), preterm delivery (OR=1.98; 95% CI, 1.59 to 2.48), low birth weight (OR=1.75; 95% CI, 1.33 to 2.32), neonatal intensive care unit (NICU) admission (OR=2.43; 95% CI, 1.61 to 3.68), intrauterine growth restriction (OR=1.44; 95% CI, 1.22 to 1.71), and Apgar score of <7 at 1 min (OR=1.78; 95% CI, 1.10 to 2.91) based on all studies but not gestational age and birth weight.

CONCLUSIONS

This meta-analysis revealed that moderate-to-severe SDB during pregnancy may be associated with most of adverse perinatal outcomes. Further well-designed studies are warranted to confirm our findings.

[Annexin A5 gene polymorphism (-1C/T) and the susceptibility to pneumoconiosis in coal works]

OBJECTIVE

To explore the role of -1C/T single nucleotide polymorphism within Annexin A5 gene in the genetic susceptibility to coal worker's pneumoconiosis (CWP).

METHODS

Four hundred and seventy CWP Han chinese patients and 428 Han chinese controls were enclosed in present case-control study. All subjects were exposed to coal dusts. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the -1C/T SNP in Annexin A5 gene for all subjects. The relationship between the -1C/T SNP in Annexin A5 gene and CWP was analyzed.

RESULTS

CT/TT genotype in -1C/T SNP was associated with a significantly decreased risk of CWP, as compared with the CC genotype among subgroups exposed to coal dusts for ≥ 27 years (adjusted OR = 0.65, 95%CI: 0.44 - 0.98, P = 0.039) and patients with CWP at stage II (adjusted OR = 0.55, 95%CI: 0.34 - 0.90, P = 0.028).

CONCLUSION

The results of present study suggest that the Annexin A5 -1C/T polymorphism may be involved in the development of CWP in Han Chinese coal miners.

Effect of thyroxine on SNARE complex and synaptotagmin-1 expression in the prefrontal cortex of rats with adult-onset hypothyroidism

Thyroid hormone insufficiency in adulthood causes a wide range of brain impairments, including altered synaptic proteins in the prefrontal cortex (PFC). The present study investigated whether adult-onset hypothyroidism altered the expression of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes and synaptotagmin-1 (syt-1) in the PFC of rats. Sprague-Dawley rats were randomly divided into 4 groups: control, hypothyroid, and hypothyroid treated with T(4) [5 or 20 μg/100 g body weight (BW)]. Adult-onset hypothyroidism was induced in rats with the antithyroid drug 6-n-propyl-2-thiouracil (ip injection). PFC levels of synaptosomal-associated protein of 25 kDa (SNAP-25), syntaxin-1, vesicle-associated membrane protein 2 (VAMP-2) and syt-1 were determined by immunohistochemistry and western blot analyses. The results showed that syntaxin-1 and syt-1 were expressed at significantly lower levels in hypothyroid rats, VAMP-2 levels were not altered, and SNAP-25 levels were much higher compared to controls. A 2-week treatment with 5 μg T(4)/100 g BW partially normalized levels of SNARE complex and syt-1, and 20 μg T(4)/100 g BW restored these proteins closer to normal levels. Our findings indicate that dysregulation of SNARE complex and syt-1 in PFC of adult-onset hypothyroidism can be restored by T(4) treatment.

Optimization of a bacterial consortium for nitrobenzene degradation

Three bacterial strains, Arthrobacter sp. NB1, Serratia sp. NB2 and Stenotrophomonas sp. NB3, were isolated from contaminated sludge by using nitrobenzene as a sole source of carbon and nitrogen. It was observed that all three strains could degrade nitrobenzene at 400 mg/L initial concentration and mixed-cultivation of these strains could enhance the degradation of nitrobenzene compared with mono-cultivation. Mixture design was used for adjusting the proportions of each strain and the optimal ratio of inoculation size was NB1:NB2:NB3 = 4:4:5, where the nitrobenzene degradation percentage was two times higher than for by the single strain. The results of Plackett-Burman design indicated that Mg(2+), Ca(2+), Fe(2+), Zn(2+) and Mn(2+) had a positive effect on the degradation of nitrobenzene, while Cu(2+) and Co(2+) had a negative effect on it.

Effect of thyroxine on synaptotagmin 1 and SNAP-25 expression in dorsal hippocampus of adult-onset hypothyroid rats

Adult-onset hypothyroidism causes cognitive dysfunctions of learning and memory, in which many synaptic proteins in hippocampus are involved. In our work, we studied the effect of adult-onset hypothyroidism on the expression of synaptotagmin 1 (syt 1) and SNAP-25 in dorsal hippocampus as well as its recovery by levothyroxine (L-T(4)) replacement therapy. Rats were divided into 4 groups: control, hypothyroidism, and hypothyroid rats treated with 5 μg T(4)/100 g body weight (BW) and 20 μg L-T(4)/100 g BW, respectively. Protein levels of syt 1 and SNAP-25 in dorsal hippocampus were determined by Western blot and immunohistochemistry. The immunoblot analysis indicated that syt 1 was expressed at a significantly lower level in hypothyroid rats, while the level of SNAP-25 was much higher compared to controls. Furthermore, using immunostaining, we found that on the one hand, expression of syt 1 was significantly down-regulated in the examined layers of CA1 and CA3 subregions but not dentate gyrus (DG); however, on the other hand, expression of SNAP-25 was up-regulated in the layers of CA1, CA3, and DG. Two-week treatment with 20 μg LT(4)/ 100 g BW fully restored the levels of syt 1 and SNAP-25 to the normal level, which was more effective than 5 μg LT(4)/ 100 g BW that partially restored the levels of both proteins. These results suggest that adult-onset hypothyroidism caused down-regulation of syt 1 and up-regulation of SNAP- 25 level in dorsal hippocampus, which could be restored by L-T(4) treatment, and the recovery degree is related to the LT(4) dosage.

The decolorisation capacity and mechanism of Shewanella oneidensis MR-1 for methyl orange and acid yellow 199 under microaerophilic conditions

Shewanella oneidensis MR-1 was found to reach 99.36% and 78.25% decolorisation for Methyl Orange and Acid Yellow 199 in solutions, respectively. The suitable pH range for decolorisation of Methyl Orange and Acid Yellow 199 by S. oneidensis MR-1 was 4.0-7.0 and 6.0-8.0, respectively, The azo dyes' removal by S. oneidensis MR-1 was slightly enhanced by addition of Mg(2+), but inhibited by Pb(2+), Cd(2+), Cu(2+), Fe(3+) and Fe(2+). The enzyme activities of NADH-DCIP reductase and azoreductase were 2.67 and 3.0 times higher, and 1.92 and 2.48 times higher, respectively, in the Methyl Orange treatment and in the Acid Yellow 199 treatment as compared to the control treatment. These findings indicated that the azo dyes' decolorisation by S. oneidensis MR-1 was via reduction mechanism.

Candida albicans THI13 disruption affects production of monocytic cytokines

INTRODUCTION

The Candida albicansTHI13 gene was identified by its homology to the Candida tropicalis CtNMT1 gene, which is involved in pyrimidine precursor biosynthesis.

METHODS

Disruption of THI13 revealed that this gene played a minor role in thiamin biosynthesis in C. albicans. Purified human monocytes were incubated with C. albicans at the optimal Candida: monocyte ratio of 0.5 and cytokines in the supernatants were measured by enzyme-linked immunosorbent assay.

RESULTS AND DISCUSSION

This experiment showed that the wild-type strain significantly induced interleukin-10 (IL-10) production but had little effect on IL-12 production, and that THI13 mutants had no significant effect on IL-10 production, though the IL-12 level was increased in the supernatants. These results suggest that THI13 is involved in the host effective immune response by regulating IL-10 and IL-12 production.

[Genetic diversity of Rh haplotypes among Chinese populations]

In the statistic study of Rh blood group system, whole Chinese data were re-calculated for haplotype frequency and linkage ratio, according to Counting Method. All Chinese majority populations and minority populations were divided into different groups, and variety genetic calculations on their gene diversity and gene differentiation were also calculated. The results shown obvious genetic differences between and among Southern and Northern Chinese populations. UPGMA phylogenetic dendrograms was plotted and the tree demonstrated that the genetic relationship among 68 Chinese populations are well corresponded with their geographical and linguistic distribution.

Routine assessment of viability in split-thickness skin

Effective quality control of allograft skin that is cryopreserved for transplantation requires a simple, reproducible technique for the assessment of cell viability. Tetrazolium reduction assays and an oxygen consumption technique have been the two methods of choice to determine the metabolic function of allograft skin after it has been thawed. In this study, we investigated the use of a novel tetrazolium salt, WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzen e disulfonate), that is cleaved to a water-soluble formazan product. Porcine split-thickness skin in minimal essential medium without cryoprotectant was subjected to a graded freezing protocol to generate progressive amounts of cryoinjury. Recovery as determined with WST-1 was compared with measurements made with the use of the oxygen consumption technique. The similarity of the resulting recovery curves indicates that WST-1 is a simple, effective, and convenient technique for the assessment of metabolic function in porcine split-thickness skin. The WST-1 assay is applicable for the routine assessment of tissue viability in cryopreserved allograft skin.

Clinical use of homograft stored by vitrification

Using 20% DMSO and 6% propylene glycol in Kreb' Ringer phosphate solution as cryopotective agent for homograft vitrification storage, the viability of stored homograft (79.2%) was higher than that of slow cooling storage (59.7%). About 540000 cm2 of vitrified homograft were used to cover the wounds after excision of burn eschar in 135 patients with major burns. The take-rate was over 94%. The cryopreservation of skin by vitrification can improve the viability and quality of skin and save time and cost.

[Effects of different cooling rate on the viability of cryopreservation of skin]

The three methods of stored skin by vitrification and slow cooling and vitrification+slow cooling were studied in order to improve the viability of stored skin. The results showed that the viability (oxygen consumptions and succinate dehydrogenase) of skin cryopreserved by vitrification was superior than by slow cooling and vitrification+slow cooling. The viability of homograft stored by vitrification was 61% compared with that for other two groups of 51.7% and 49.2% (P < 0.05). So the skin stored by this vitrification may be suitable for clinical use.

Semi-differential voltammetry with carbon fiber electrodes for in vivo determination of monoamine metabolites and ascorbic acid in rat corpus striatum

Carbon fiber electrodes combined with semi-differential voltammetry were used to determine endogenous monoamine metabolites and ascorbic acid (AA). These electrodes treated by a new electrochemical procedure (30 microA for 30 s, then -2 V for 10 s) showed a significant improvement on the sensitivity and selectivity. In the rat corpus striatum, these electrodes allowed a distinct separation and continuous detection of AA, 3, 4-dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) simultaneously. The normal striatal levels of AA, DOPAC, and 5-HIAA were found to be 168.2 +/- 19.5, 21.4 +/- 3.9, and 3.3 +/- 0.5 mumol.L-1. Our method is credible for detecting the changes of monoamine metabolite contents induced by pharmacologic manipulations.

[Improvement in the method of determination of succinic dehydrogenase in skin]

The authors improved Hershey's measurement of succinic dehydrogenase in the shin. Liquid paraffin was used to replace nitrogen gas sealing. The values of succinic dehydrogenase of guinea pig skin which was kept at 4 degrees C for 2, 4, 6, 8, 10 days were measured by two methods. There were no significant differences between the values measured by two methods (P greater than 0.05). Our method is simpler, more convenient and have good correlation with Hershey's method (r = 0.929).

[Dynamic changes in serum levels of T3 and T4 in burn patients and its clinical significance]

From May 1985 to May 1987, dynamic changes in T3 and T4 in serum of 34 burn patients were measured by radio-immunodiffusion method. Among them, 10 patients died. The normal levels of T3 and T4 in serum of 30 healthy person are presented. The levels of T3 and T4 in every burn groups were lower significantly than in normal healthy person group (P less than 0.01). After 3 days of burn injury, the levels of T3 and T4 in serum were low on 3 days postburn and were lowest on 30 days postburn. T3 in serum was markedly higher before sepsis than after sepsis (P less than 0.01) and T4 in serum was lower before sepsis than after sepsis. But no significant difference was found (P greater than 0.05). It also showed that the levels of T3, T4 were higher in groups of non-sepsis and survival than in those of sepsis and death. The results suggest that determination of T3 and T4 in serum are valuable to diagnose and predict the prognosis of sepsis in burn injuries.

The use of blood in burn shock. Clinical and experimental study

We have given whole blood as one of the main constituents of burn shock resuscitation for the past 28 years. To appraise the value of using whole blood, we have summarized the clinical experience of 2630 burn patients. Overall mortality was 4.18%. The lethal area of the burn were 50% of the population is expected to die was 82.8% total body surface area and 57.4% third-degree burns. The incidence of renal failure, pulmonary edema, and gastrointestinal bleeding was 0.9%, 0.4%, and 0.6% respectively. To confirm the advantage of transfusion of whole blood, we have carried out a series of experimental studies. Two groups of 25 dogs with 25% total body surface area full-thickness burns were treated with two resuscitation regimens. Group I was treated with whole blood, and group II with no blood, during the shock phase. After 48 hours, the infusions were stopped. Measurements were made before the burn and 2, 24, 48, 72, and 144 hours after the burn injury. The animals were then killed for histologic studies. From our data, we concluded that whole blood used in burn shock did not increase hemoconcentration or viscosity; it improved anemia, oncotic pressure, hypoproteinemia, acid-base balance, oxygenation, hemodynamics, and myocardial contractility, promoted cardionatrin secretion, reduced edema of tissue, and protected viscera from degenerative changes and bacterial colonization.

Changes in plasma fibronectin levels in burn patients

Plasma fibronectin was determined in 180 healthy individuals. No significant difference was found between males and females: therefore the values were pooled. The mean value was 286.94 +/- 51.35 micrograms/ml. In 24 patients with burns covering 30-95 per cent of the total body surface area (TBSA), plasma fibronectin was determined sequentially. There was a significant lowering in plasma fibronectin (FN) values in all cases on post-burn day 1 (112.56-185.85 micrograms/ml) and post-burn day 2 (44.03-298.0 micrograms/ml). The concentrations returned to within the normal range in 19 survivors within 3-6 days. In five non-survivors, plasma FN levels fell progressively until death. In another nine patients with burns ranging from 3 per cent to 25 per cent TBSA, plasma FN level was found to be normal on post-burn day 1. The likely causes of the reduced concentrations of plasma fibronectin in patients with burn injuries are briefly discussed. It seems that the level of plasma fibronectin may be used as a prognostic index in burn patients.