Spatiotemporal Changes of Antibiotic Resistance, Potential Pathogens, and Health Risk in Kindergarten Dust.

The microorganisms present in kindergartens are extremely important for children's health during their three-year preschool education. To assess the risk of outdoor dust in kindergartens, the antibiotic resistome and potential pathogens were investigated in dust samples collected from 59 kindergartens in Xiamen, southeast China in both the winter and summer. Both high-throughput quantitative PCR and metagenome analysis revealed a higher richness and abundance of antibiotic resistance genes (ARGs) in winter (P < 0.05). Besides, the bloom of ARGs and potential pathogens was evident in the urban kindergartens. The co-occurrence patterns among ARGs, mobile genetic elements (MGEs), and potential pathogens suggested some bacterial pathogens were potential hosts of ARGs and MGEs. We found a large number of high-risk ARGs in the dust; the richness and abundance of high-risk ARGs were higher in winter and urban kindergartens compared to in summer and peri-urban kindergartens, respectively. The results of the co-occurrence patterns and high-risk ARGs jointly reveal that urbanization will significantly increase the threat of urban dust to human beings and their risks will be higher in winter. This study unveils the close association between ARGs/mobile ARGs and potential pathogens and emphasizes that we should pay more attention to the health risks induced by their combination.

Movement of protistan trophic groups in soil-plant continuums.

Protists, functionally divided into consumers, phototrophs, and parasites act as integral components and vital regulators of microbiomes in soil-plant continuums. However, the drivers of community structure, assembly mechanisms, co-occurrence patterns, and the associations with human pathogens and different protistan trophic groups remain unknown. Here, we characterized the phyllosphere and soil protistan communities associated with three vegetables under different fertilization treatments (none and organic fertilization) at five growth stages. In this study, consumers were the most diverse soil protist group, had the role of inter-kingdom connector, and were the primary biomarker for rhizosphere soils which were subjected to decreasing deterministic processes during plant growth. In contrast, phototrophs had the greatest niche breadth and formed soil protistan hubs, and were the primary biomarkers for both bulk soils and the phyllosphere. Parasites had minimal input to microbial co-occurrence networks. Organic fertilization increased the relative abundance (RA) of pathogenic protists and the number of pathogen-consumer connections in rhizosphere soils but decreased protistan richness and the number of internal protistan links. This study advances our understanding of the ecological roles and potential links between human pathogens and protistan trophic groups associated with soil-plant continuums, which is fundamental to the regulation of soil-plant microbiomes and maintenance of environmental and human health.

Convolutional neural network based anatomical site identification for laryngoscopy quality control: A multicenter study.

OBJECTIVES: Video laryngoscopy is an important diagnostic tool for head and neck cancers. The artificial intelligence (AI) system has been shown to monitor blind spots during esophagogastroduodenoscopy. This study aimed to test the performance of AI-driven intelligent laryngoscopy monitoring assistant (ILMA) for landmark anatomical sites identification on laryngoscopic images and videos based on a convolutional neural network (CNN). MATERIALS AND METHODS: The laryngoscopic images taken from January to December 2018 were retrospectively collected, and ILMA was developed using the CNN model of Inception-ResNet-v2 + Squeeze-and-Excitation Networks (SENet). A total of 16,000 laryngoscopic images were used for training. These were assigned to 20 landmark anatomical sites covering six major head and neck regions. In addition, the performance of ILMA in identifying anatomical sites was validated using 4000 laryngoscopic images and 25 videos provided by five other tertiary hospitals. RESULTS: ILMA identified the 20 anatomical sites on the laryngoscopic images with a total accuracy of 97.60 %, and the average sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 100 %, 99.87 %, 97.65 %, and 99.87 %, respectively. In addition, multicenter clinical verification displayed that the accuracy of ILMA in identifying the 20 targeted anatomical sites in 25 laryngoscopic videos from five hospitals was ≥95 %. CONCLUSION: The proposed CNN-based ILMA model can rapidly and accurately identify the anatomical sites on laryngoscopic images. The model can reflect the coverage of anatomical regions of the head and neck by laryngoscopy, showing application potential in improving the quality of laryngoscopy.

THz imaging technique for nondestructive analysis of debonding defects in ceramic matrix composites based on multiple echoes and feature fusion.

We propose a THz nondestructive analysis method based on multiple echoes and feature fusion. Conventionally, it is difficult to identify the debonding defects of the glue layer (II) due to the thin adhesive layer. To this end, a THz propagation model is established, and a quantitative method for determining the thickness of debonding defects based on multiple echoes is presented. The measurement error for preset defect thickness of 500 µm was 4%. Further, for determining the area of debonding defects, a feature fusion imaging algorithm is proposed to realize the lateral recognition of defects and quantitative analysis is used to improve the recognition ability of defects.

Copy number variation of MYLK4 gene and its growth traits of Capra hircus (goat).

Copy number variation (CNV) is a form of genetic variation caused by genome rearrangement, with abnormal fragments ranging from 50 bp to Mb. And, CNV is closely related to disease, growth and reproductive shape of livestock. As a member of myosin light chain kinase (MYLK) family with serine/threonine specificity, MYLK4 belongs to an enzyme encoded by MYLK4 gene. Although MYLK4 is a recognized kinase, its function has yet to be revealed in subsequent studies. This study aims to analyze CNV and genetic effects of MYLK4 gene in goats. We used qPCR to detect CNV of MYLK4 gene in African Nubian goat (n = 32), Guizhou black goat (n = 196) and Guizhou white goat (n = 95), respectively, and correlated CNV data of MYLK4 gene with goat growth traits in Chinese goats. The results showed that the effect of MYLK4 gene CNV on body weight, body length and body height of goats had significantly different (p < 0.05, Q < 0.05), in which CNV showed better growth traits in type of deletion. Therefore, CNV of MYLK4 gene can be used as a molecular marker for assisted selection of goat growth traits, which provides a theoretical basis for the genetic improvement of goat breeds in China.

[Effects of Geniposide on the Neuroinflammation in Chronic Cerebral Hypoperfusion Rat Model].

OBJECTIVE: To investigate the effects and the mechanism of geniposide on the neuroinflammation occured in the neurodegeneration course of a chronic cerebral hypoperfusion rat model. METHODS: Permanent bilateral common carotid arteries occlusions was performed to induce gradient cognitive deficit in rats. The sham group was used as control group. Then 18 rats that met the Screening Criteria were randomly selected 8 weeks post surgery, and were randomly divided into three groups, the 2-VO rats with saline solution group (2-VO+saline group), 2-VO rats with 50 mg/kg per day geniposide group (2-VO+G50) and 2-VO rats with 100 mg/kg per day geniposide group (2-VO+G100). All intervention groups were daily administered with geniposide or saline for 4 weeks. The sham-operated rats were administrated with saline. Then the rats were tested for Morris water maze to evaluate the memory and learning ability. Rats were sacrificed to obtain cortex and hippocampus tissues for HE staining and to detect expression level of glial fibrillary acidic protein (GFAP), inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB), and the level of inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin (IL)-6. RESULTS: The 2-VO+saline group rats showed significant longer escape latency and less percent time in target quadrant, compared with sham-operation group ( P<0.05). The escape latency of 2-VO+G50 and 2-VO+G100 groups were shorter than the 2-VO+saline group ( P<0.05), but still longer than the sham group ( P<0.05), the percent time in target quadrant of which were more than the 2-VO+saline group and less than the sham group. However, there was no significant difference between these two groups. HE staining of sham group showed that neurons in the cortex and hippocampus lined up in order, cellar nucleus were big and globular. HE staining results showed that there were obviously neuoral cells loss, severe cytomorphosis, structural disappearance and nuclear fragmentation in the 2-VO+saline group. The 2-VO+G50 and 2-VO+G100 groups showed less neurodamage than the 2-VO+saline group with less neuoral cells loss, cytomorphosis and ambiguous nucleus. GFAP, iNOS, NF-κB were all highly expressed in the process of cognitive dysfunction in rats after chronic cerebral ischemia, however geniposide intervention (50 and 100 mg/kg per day) significantly decreased the expression of the above proteins. In addition, much more TNF-α and IL-6 were released in brain induced by chronic cerebral ischemia, and the levels were decreased after chronic geniposide oral treatment. No significant differences were detected between 2-VO+G50 and 2-VO+G100 groups. CONCLUSION: These findings demonstrated that geniposide significantly prevented cognition deterioration induced by chronic cerebral hypoperfusion in rats. Geniposide inhibited neuroinflammation occurred in the process of chronic cerebral ischemia probably via reducing iNOS and NF-κB expression and suppressing the release of inflammatory factor TNF-α and IL-6.

Spectrums and Outcomes of Adnexal Torsion at Different Ages.

OBJECTIVES: To investigate the role of ultrasound in the preoperative diagnosis of adnexal torsion and describe its histological spectrum and outcomes at different ages. METHODS: This study comprised a retrospective investigation of a data set that included 195 female patients with clinically suspected adnexal torsion between January 2010 and July 2015. Each patient received a detailed pelvic ultrasound examination by an experienced ultrasound examiner, and a definitive diagnosis was achieved via surgery. The accuracy of an ultrasonic diagnosis of adnexal torsion was assessed. The patients were divided into three groups: female children and adolescents, fertile women, and postmenopausal women. The size, type, histological spectrum, and outcome of adnexal torsion in the different groups were also described. RESULTS: The sensitivity, specificity, and accuracy of ultrasound were 0.84, 0.77, and 0.81, respectively. There were significant differences in the presence of ultrasonic hallmarks among the true positive, false positive, and false negative cases of adnexal torsion. Ovarian torsion was identified in 94 cases, and isolated tubal torsion was identified in 15 cases. The most common histologic diagnoses of the pediatric group and the other two groups were a normal ovary and teratoma, respectively. The most common histologic diagnoses in the cases of isolated tubal torsion were mesosalpinx cyst and oviduct inflammation. CONCLUSIONS: Ultrasonography plays an important role in the preoperative diagnosis of adnexal torsion. Despite ovarian involvement in most of the cases, isolated oviduct torsion was not uncommon. The spectrum of histological diagnoses varied among the age groups.

[Expression of PTEN in Myocardial Tissue in Coronary Heart Disease].

OBJECTIVE: To observe the expression of phosphatase and tensin homology deleted on chromosome ten (PTEN) in myocardial tissue in patients with coronary heart disease, and explore the relevance between the expression of PTEN and the occurrence and development of coronary heart disease. METHODS: A total of 16 death cases with pathological diagnosis of coronary heart disease were collected as experimental group, and 19 cases without myocardial lesions were selected as control group. The expression of PTEN protein and its mRNA were detected by immunohistochemistry and real-time fluorescence quantitative PCR respectively. The correlation between the expression of PTEN and the pathogenesis of coronary heart disease was analyzed. RESULTS: The expression of PTEN protein in myocardium in cases with coronary heart disease was significantly lower compared with the control group (P < 0.05). There was no statistical difference of the expression of PTEN mRNA between experimental and control group (P > 0.05). CONCLUSION: PTEN may be involved in the occurrence and development of coronary heart disease.

A sensitive assay for trypsin using poly(thymine)-templated copper nanoparticles as fluorescent probes.

A new, simple and sensitive fluorescence strategy was developed for the trypsin assay based on copper nanoparticles (CuNPs) and its different fluorescence response toward trypsin-catalyzed hydrolysis of cytochrome c (Cyt c). Polythymine (poly T)-templated CuNPs served as effective fluorescent probes. Cyt c is well-known to act as a quencher. However, herein, a low concentration of Cyt c was designed specially to act as the substrate of trypsin to avoid the quenching effects by electron transfer from Cyt c to CuNPs. In the presence of trypsin, Cyt c hydrolyzes to small peptides, releasing free cysteine residues. Nonfluorescent coordination complexes were formed upon exposure to free cysteine residues by a metal-ligand bond between Cu atoms and sulfur atoms, leading to a decreased fluorescence response to CuNPs. This novel method for the quantitative determination of trypsin has a linear detection range from 0.25 µg mL(-1) to 1000 µg mL(-1) and a relatively low detection limit of 42 ng mL(-1). To the best of our knowledge, this is the first application of the trypsin-catalyzed hydrolysis reaction of Cyt c to produce quenching effect in bioanalysis, which provided a novel approach for the biochemical sensing strategy.

Procalcitonin guidance for reduction of antibiotic use in patients hospitalized with severe acute exacerbations of asthma: a randomized controlled study with 12-month follow-up.

INTRODUCTION: Patients with severe acute exacerbations of asthma often receive inappropriate antibiotic treatment. We aimed to determine whether serum procalcitonin (PCT) levels can effectively and safely reduce antibiotic exposure in patients experiencing exacerbations of asthma. METHODS: In this randomized controlled trial, a total of 216 patients requiring hospitalization for severe acute exacerbations of asthma were screened for eligibility to participate and 169 completed the 12-month follow-up visit. Patients were randomized to either PCT-guided (PCT group) or standard (control group) antimicrobial therapy. In the control group, patients received antibiotics according to the attending physician's discretion; in the PCT group, patients received antibiotics according to an algorithm based on serum PCT levels. The primary end point was antibiotic exposure; secondary end points were clinical recovery, length of hospital stay, clinical and laboratory parameters, spirometry, number of asthma exacerbations, emergency room visits, hospitalizations and need for corticosteroid use due to asthma. RESULTS: PCT guidance reduced antibiotic prescription (48.9% versus 87.8%, respectively; P < 0.001) and antibiotic exposure (relative risk, 0.56; 95% confidence interval, 0.44 to 0.70; P < 0.001) compared to standard therapy. There were no significant differences in clinical recovery, length of hospital stay or clinical, laboratory and spirometry outcomes in both groups. Number of asthma exacerbations, emergency room visits, hospitalizations and need for corticosteroid use due to asthma were similar during the 12-month follow-up period. CONCLUSION: A PCT-guided strategy allows antibiotic exposure to be reduced in patients with severe acute exacerbation of asthma without apparent harm. TRIAL REGISTRATION: Chinese Clinical Trial Register ChiCTR-TRC-12002534 (registered 26 September 2012).

Fetal persistent left superior vena cava in cases with and without chromosomal anomalies.

OBJECTIVES: The objectives of this study are to determine and compare the prevalence of persistent left superior vena cava (PLSVC) in chromosomally normal and abnormal fetuses and to evaluate the potential of PLSVC as a screening marker for chromosomal abnormalities. METHODS: Women undergoing routine fetal sonographic examinations were evaluated once for the presence of PLSVC. PLSVC was diagnosed on the basis of the identification of an additional vessel in the left of the pulmonary artery in a three-vessel trachea view. Associated abnormalities, karyotypes, and outcomes were analyzed. RESULTS: A total of 164 (0.7%, 164/25 171) cases of PLSVC were detected and successfully followed-up. The detection rates were 0.5% (81/17 535) and 1.1% (83/7636) in the low-risk and high-risk cases, respectively. The incidence of PLSVC was lower among the chromosomally or clinically normal (0.4%, 110/24 914) compared with chromosomally abnormal fetuses (7.8%, 20/257, p < 0.001). Additional defects were identified in 90% (18/20) of the PLSVC fetuses with chromosomal anomalies, a rate that was higher than those fetuses with chromosomal normal (61.8%, 68/110). CONCLUSIONS: Persistent left superior vena cava is more common among chromosomally abnormal than normal fetuses, and PLSVC fetuses with other defects are more highly associated with chromosomal disorders than isolated PLSVC fetuses. Isolated PLSVC is a benign vascular anomaly and may not affect outcomes.

Prenatal diagnosis of prevalence of the right heart: associated anomalies and outcome predictors.

OBJECTIVES: To analyze the characteristics, associations, and outcomes of prevalence of the right heart and to evaluate the use of sonography to predict the risk of a poor prognosis in fetuses with this condition. METHODS: We conducted a retrospective cohort study of 182 fetuses with prevalence of the right heart. At the initial evaluation, the left ventricle (LV) and right ventricle (RV) sizes, left atrium and right atrium sizes, great artery diameters, appearance of the aortic arch and ductus arteriosus arch, and flow direction across the foramen ovale and aortic arch were documented. Malformations were documented in fetuses with intracardiac anomalies, who were divided into groups with and without coexisting extracardiac defects. The RV-LV diameter ratio and main pulmonary artery-to-aortic root diameter ratio were calculated and compared. The following variables were analyzed: coexisting intracardiac anomalies, associated extracardiac anomalies, diagnosis before 24 gestational weeks, fetal growth restriction, reversed flow across the foramen ovale, reversed flow in the aortic arch, and RV-LV ratio greater than 2.0. Relationships between these sonographic findings and the prognosis were evaluated by multivariable logistic regression. RESULTS: Of the 182 fetuses, 1 (0.5%) had intrauterine death, and 25 (13.7%) had neonatal death; 1 (0.5%) had selective reduction, and 106 (58.2%) underwent termination of pregnancy; 49 (26.9%) survived at this writing. The mean RV-LV ratio was 1.67. Multivariable logistic regression revealed that only 2 sonographic parameters, coexisting intracardiac anomalies (odds ratio, 17.75; 95% confidence interval, 4.18-75.26) and diagnosis before 24 weeks (odds ratio, 17.26; 95% confidence interval, 1.80-165.39) were significantly associated with a poor prognosis. CONCLUSIONS: The sonographic parameters of coexisting intracardiac anomalies and diagnosis before 24 gestational weeks are significant independent predictors of a poor prognosis in fetuses with prevalence of the right heart. Combinations of these risk factors may be useful in prenatal consultation.

[General integral medicine: the strategic direction for complex health interventions].

Nowadays, the simple combination of Western medicine (WM) and complementary and alternative medicine (CAM) cannot resolve all the health problems and various requirements. This article proposed the general integral medicine (GIM) theoretical model, which declares the disease causes analysis, clinical intervention and outcomes assessment should be recognized, managed and evaluated both from physiological, psychological, and spiritual status, and all the four dimensions: orthodox medicine (WM, Chinese medicine, etc.), individual inherent characteristics (emotion, attitude, psychology, etc.), cultural influences (doctors, caregivers, groups care, etc.), and natural environment and social systems (economic status, social security system, environmental pollution, etc). As for health outcomes assessment, a more comprehensive system including biological, doctors, patients, health intimate, social and environmental evaluations were required. The GIM model has individualized, dynamic, standardized, objective, systematic inherent characteristics, and opening and compatible external characteristics. It aims to provide the new theoretical guidance and strategic development direction for complex health interventions, and solve various medical related psychological and social problems.

Psilocybin for major depressive disorder: a systematic review of randomized controlled studies.

Objectives: The purpose of this systematic review of randomized controlled trials (RCTs) was to evaluate the effectiveness, safety, and tolerability of psilocybin in adult patients with major depressive disorder (MDD). Methods: A systematic search (up to September 14, 2023) was conducted for RCTs that examined the efficacy, safety, and tolerability of psilocybin in physically healthy adult patients with MDD. Three independent researchers extracted data from publications where the primary outcome was a change in depressive symptoms, and key secondary outcomes were changes in anxiety symptoms and suicidal ideation, discontinuation rates for any reason, and adverse drug reactions (ADRs). Results: Five RCTs with 472 adult patients with MDD on psilocybin (n = 274) and controls (n = 198) were included. Two of the five RCTs (40%) reported mixed results, while the other three (60%) found that psilocybin had a beneficial effect on MDD treatment. Four RCTs (80%) assessing the anxiolytic effects of psilocybin for treating MDD found that psilocybin was significantly more effective than the control group in improving anxiety symptoms. Psilocybin was more effective than the control group in improving suicidal ideation in one out of five RCTs. Discontinuation rates were similar for any reason between the psilocybin group (2-13%) and the control group (4-21%) (P > 0.05). Four RCTs (80%) reported ADRs in detail. The most common ADR in both groups was headache. Conclusion: Psilocybin was effective in improving depressive symptoms in over half of the included studies and reduced anxiety symptoms in patients with MDD. The long-term efficacy and safety of psilocybin for MDD treatment needs to be further investigated in large RCTs.

High-risk ARGs (HRA) Chip: A high-throughput qPCR-based array for assessment of high-risk ARGs from the environment.

The global surge in antibiotic resistance genes (ARGs) presents a serious public health challenge. While methods like metagenomic analysis and qPCR arrays have been instrumental in investigating ARG distributions and dynamics, the vast diversity of ARGs often complicates effective monitoring and risk assessment. Here, we developed a High-Risk ARGs (HRA) chip based on high-capacity quantitative PCR array targeting previously identified high-risk ARGs. These ARGs are known to be prevalent in human-related environments, exhibit gene mobility, and are present in ESKAPE pathogens. The HRA chip include 101 primer sets and the 16S rRNA gene as a reference. These primer sets consist of 34 obtained from previous studies, and 67 newly designed primer sets which were validated in silico and experimentally. Absolute quantification of targeted ARGs is accomplished by generating standard curves for all ARGs with serially ten-fold diluted mixed plasmids containing targeted ARG sequences. The amplification efficiencies of all ARGs exceed 99% via plasmid template dilution tests, suggesting high reliability in quantification. The performance of HRA chip is further evaluated by practical applications in environmental samples from wastewater treatment plants (WWTPs) and soils with various land use types and fertilization regimes. The results indicate the dynamics of high-risk ARGs during wastewater treatment process, and reveal the profiles of soil high-risk ARGs which is distinct from those derived via metagenomic approaches. These findings highlight the potentials of HRA Chip in the evaluation of anthropogenic impacts on the environmental resistome with a more focused spectrum of high-risk ARGs. Overall, the HRA Chip emerges as a powerful and efficient high-throughput tool for rapid detection and quantification of high-risk ARGs, facilitating comprehensive profiling of high-risk resistomes in environmental samples which is essential for human health risk assessment of ARGs.

Shifts in reproductive strategies in the evolutionary trajectory of plant lineages.

Understanding the maintenance and shift in reproductive strategies is a fundamental question in evolutionary research. Although many efforts have been made to compare different reproductive strategies, the association between reproductive strategies and lineage divergence is largely unknown. To explore the impact of different reproductive strategies on lineage divergence, we investigated the evolution of clonality in Saxifraga sect. Irregulares+Heterisia. By integrating several lines of evidence, we found that the loss of clonality in Irregulares+Heterisia was associated with a progressive increase in diversification rate and intraspecific morphological diversity but with a reduction in species distribution range. Our findings provide insights into the ecological and evolutionary effects of different reproductive strategies, suggesting the necessity of integrating clonality into ecological and evolutional research.

A genetic variant in the promoter region of miR-34b/c is associated with a reduced risk of colorectal cancer.

The miR-34 family members, described as potential tumor suppressors, were downregulated in colorectal cancer (CRC). Loss of miR-34 impairs TP53-mediated cell death, while overexpression of miR-34 induces apoptosis. A potentially functional polymorphism (i.e., rs4938723T/C) in the promoter region of pri-miR-34b/c was predicted to influence the GATA-X binding sites. We aimed to investigate the association between miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms and the risk of CRC. We genotyped the two polymorphisms in 347 CRC patients and 488 healthy controls using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing assay. We found that the CC genotype and C allele of the miR-34b/c rs4938723 were associated with a significantly decreased risk of CRC compared with the TT genotype and T allele (CC vs. TT: adjusted OR=0.56; 95% CI, 0.34-0.91; C vs. T: adjusted OR=0.78; 95% CI, 0.64-0.97). In combined analysis, a borderline significance was also observed in subjects carrying the rs4938723 CT/CC and TP53 GG genotypes (adjusted OR=0.66; 95% CI, 0.43-0.99). These findings indicate that the rs4938723 in the promoter region of pri-miR-34b/c was a protective factor for the development of CRC. As the significance is marginal, further replication studies are warranted to confirm these results.

The reorganization of actin filaments is required for vacuolar fusion of guard cells during stomatal opening in Arabidopsis.

The reorganization of actin filaments (AFs) and vacuoles in guard cells is involved in the regulation of stomatal movement. However, it remains unclear whether there is any interaction between the reorganization of AFs and vacuolar changes during stomatal movement. Here, we report the relationship between the reorganization of AFs and vacuolar fusion revealed in pharmacological experiments, and characterizing stomatal opening in actin-related protein 2 (arp2) and arp3 mutants. Our results show that cytochalasin-D-induced depolymerization or phalloidin-induced stabilization of AFs leads to an increase in small unfused vacuoles during stomatal opening in wild-type (WT) Arabidopsis plants. Light-induced stomatal opening is retarded and vacuolar fusion in guard cells is impaired in the mutants, in which the reorganization and the dynamic parameters of AFs are aberrant compared with those of the WT. In WT, AFs tightly surround the small separated vacuoles, forming a ring that encircles the boundary membranes of vacuoles partly fused during stomatal opening. In contrast, in the mutants, most AFs and actin patches accumulate abnormally around the nuclei of the guard cells, which probably further impair vacuolar fusion and retard stomatal opening. Our results suggest that the reorganization of AFs regulates vacuolar fusion in guard cells during stomatal opening.

[Study on the dendritic cell subsets in peripheral blood and its relationship with the expressions of Gata-3 and T-bet in lymphocytes of patients with immune thrombocytopenia].

OBJECTIVE: To explore the relationship between the dendritic cell (DC) subsets and abnormal expression of transcription factors Gata-3 and T-bet in patients with immune thrombocytopenia (ITP). METHODS: The plasmacytoid DC (pDC) and myeloid DC (mDC) of 33 ITP (16 untreated, 17 remitted) patients and 12 healthy controls were analyzed by flow cytometry (FCM) . The expressions of Gata-3 mRNA and T-bet mRNA in peripheral blood mononuclear cell (PBMNC) were detected by reverse transcription-polymerase chain reaction (RT-PCR) .The levels of interleukin-4 (IL-4) and interferon-gamma (IFN-γ) were measured by FCM in 33 ITP patients and 12 healthy controls. RESULTS: The percentage of pDC in PBMNC was 0.49% ± 0.18% in untreated and it was higher than that in remitted ITP patients (0.27% ± 0.17%) and in controls (0.32% ± 0.13%) (both P < 0.05). The percentage of mDC in PBMNC was 0.23% ± 0.17% in untreated, which was lower than that in remitted ITP patients (0.33% ± 0.18)% and in controls (0.31% ± 0.11%), but no statistic difference in mDC expression existed among 3 groups (P > 0.05). pDC/mDC ratios was (3.15 ± 2.01) in untreated ITP patients and it was higher than that in remitted ITP patients (0.81 ± 0.32) and in controls (1.07 ± 0.44) (both P < 0.05). The relative mRNA expression levels of Gata-3 were 2775 ± 489, 1357 ± 307 and 652 ± 165 respectively. And the expression of Gata-3mRNA in untreated group was higher than that in remission group or healthy controls (both P < 0.05). The relative mRNA expression levels of T-bet were 782 ± 394, 583 ± 176 and 576 ± 120. No statistic difference in T-bet expression existed among 3 groups (P > 0.05). Gata-3mRNA/T-bet mRNA ratio was (4.13 ± 1.69 ) in untreated group and it was higher than that of remission group (2.45 ± 0.69) or controls (1.15 ± 0.27) (both P < 0.05). The level of IL-4 in the untreated group was 9.14% ± 4.34% and it was higher than that of remission group (4.78% ± 1.69%) or controls (4.86% ± 1.41%). The level of IFN-γ in the untreated group was lower than that of controls (P < 0.05). Significant positive correlations existed between Gata-3 and pDC/mDC ratio (r = 0.585, P < 0.01). Significant positive correlations existed between Gata-3 and IL-4 ( r = 0.463, P < 0.05). CONCLUSION: The mechanism of ITP may be due to a disorder of DC subsets and a high expression of Gata-3.

[Inhibitory effects of tacrolimus on effector T cells from patients with severe aplastic anemia].

OBJECTIVE: To explore the inhibitory effects of tacrolimus (FK506) on effector T cells in vitro and examine the relationship between effector T cells and clinical features in patients with severe aplastic anemia (SAA) to elucidate its immune mechanism. METHODS: The CD8(+) HLA-DR(+) cells, sorted by immunomagnetic separation from bone marrow mononuclear cells (BMMNC) of 16 SAA patients, were cultured in different concentrations of interleukin-2 (IL-2) alone or with FK506 for 72 hours. The proliferation effect was measured with methyl thiazolyl tetrazolium (MTT) method. The T lymphocytes were sorted from the SAA patients by lymphocyte separation medium and cultured alone or with IL-2 or with FK506 or FK506 plus cyclosporin A (CsA) for 18 hours. The expression of tumor necrosis factor-ß (TNF-ß) in CD8(+) HLA-DR(+) T cells was analyzed by flow cytometry. The relationship between the expression of TNF-ß and the clinical data, including percentages of reticulocyte and lymphocytes in peripheral blood cell count and ratio of CD4(+) T cells and CD8(+)T cells, was also analyzed. RESULTS: At the concentration of IL-2 greater than or equal to 20 U/ml, the cell proliferation (A values, 0.538 ± 0.142) were significantly higher than that in the blank culture hole (0.505 ± 0.153) (P < 0.05). The A values significantly decreased (0.386 ± 0.124) after the addition of FK506 (P < 0.05). Compared with control group, the expression of TNF-ß was significantly higher in IL-2 group (73.36% ± 16.73% vs 66.61% ± 16.20%, P < 0.05), significantly lower in FK506 and FK506 plus CsA groups (P < 0.05). No significant differences existed between the FK506 and FK506 plus CsA groups (47.78% ± 20.09% and 42.23% ± 21.35%, P > 0.05). The expression of TNF-ß in SAA was negatively correlated with the percentage of reticulocyte and the ratio of CD4(+) T cell and CD8(+) T cell, positively correlated with the percentage of lymphocyte in peripheral blood count (r = -0.86, -0.90, 0.77, all P < 0.05). CONCLUSIONS: IL-2 can enhance the proliferation and expression of TNF-ß of CD8(+)HLA-DR(+)T cells from SAA patients. Such an effect is inhibited by FK506. And FK506 and FK506 plus CsA have similar effects.