Rab3a attenuates spinal cord injury by mediating vesicle release.

BACKGROUND: Rab3a regulates vesicle secretion and transport. Emerging evidences have shown that extracellular vesicles (EVs) can reach target lesions of injured spinal cords and exert a positive effect on these lesions. However, the molecular mechanism by which Rab3a regulates vesicle secretion to ameliorate spinal cord injury (SCI) is not fully understood. METHODS: An SCI rat model was established which was used to examine the pathological changes and Rab3a expression in spinal cord tissue. Rab3a was overexpressed in the model rats to demonstrate its effect on SCI repair. Rab3a was also knocked down in neuronal cells to verify its role in vesicle secretion and neuronal cells. The binding protein of Rab3a was identified by Co-IP and mass spectrometry. RESULTS: Rab3a was significantly downregulated in SCI rats and Rab3a overexpression promoted SCI repair. Rab3a knockdown inhibited the secretion of neuronal cell-derived EVs. Compared to the EVs from the equal number of control neuronal cells, EVs from Rab3a-knockdown neuronal cells promoted M1 macrophage polarization, which in turn, promoted neuronal cell apoptosis. Mechanistically, STXBP1 was identified as a binding protein of Rab3a, and their interaction promoted the secretion of neuronal cell-derived EVs. Furthermore, METTL2b was significantly downregulated in SCI rats, and METTL2b knockdown significantly reduced Rab3a protein expression. CONCLUSION: These results suggest that Rab3a promotes the secretion of neuronal cell-derived EVs by interacting with its binding protein STXBP1. Neuronal cells-derived EVs inhibited the polarization of M1 macrophages in the spinal cord microenvironment, thereby promoting SCI repair. Our findings provide a theoretical basis for the clinical treatment of SCI.

Myopia among children and adolescents: an epidemiological study in Fuzhou City.

Objective: To provide a reference for the prevention and control of myopia by analyzing and discussing the findings of an epidemiological survey of the prevalence of myopia among children and adolescents in Fuzhou City from 2019 to 2021. Methods: Participants for this cross-sectional study were drawn from Gulou District and Minqing County in Fuzhou City using cluster random sampling to account for differences in population density, economic development, and other environmental variables. Results: Myopia was more prevalent in 2020 than in 2019, but by 2021 it had dropped to about the same level as in 2019. Myopia was more prevalent among girls than boys during the course of the study period, with a three-year prevalence of 44.72% for boys and 52.16% for girls. Mild myopia accounted for 24.14% of all cases, followed by moderate myopia at 19.62%, and severe myopia at 4.58%. Students in urban regions had a prevalence of myopia equivalent to that of students in the suburbs, and this prevalence rose with age. Conclusion: Myopia was quite prevalent among children and adolescents in Fuzhou City, and was shown to be steadily rising as students progressed through the school system. This suggests that all levels of government, educational institutions, medical facilities, and concerned parents in Fujian Province should focus on the issue of myopia and collaborate to reduce the risk factors for the development of myopia in school-aged participants.

Rat Bait, Not Healthy Rice!

Bromadiolone, a potent, long-acting anticoagulant rodenticide is frequently tinted to a red or pink color and mixed with cereals as rat bait. Six peoples working in a small factory suffered from a severe bleeding tendency several weeks after consuming a rice meal that was tainted with bromadiolone mistaken to be healthy food. High serum levels of bromadiolone and excessive bleeding were found in these individuals, and they needed vitamin K1 therapy for weeks. These cases indicated that long-acting anticoagulant rodenticide might induce cumulative toxicity in repeated, low-dose exposure, and the blood levels of bromadiolone might be an indicator for antidote therapy if available.

Oral administration of injectable vitamin K1 in brodifacoum intoxication.

Brodifacoum is a highly potent and long-acting anticoagulant rodenticide (LAAR). LAAR poisoning possibly leads to long term bleeding problems and needs vitamin K1 treatment for several months. Due to economic concern, tablet preparation of vitamin K1 was not available in most of the countries, including Taiwan. In literature, few reports had pointed out that injectable form of vitamin K could be used orally in patients on anticoagulant therapy with supratherapeutic state. Here, we reported a family with 3 members suffering from brodifacoum poisoning with severe coagulopathy needed to prolong hospitalization for intravenous vitamin K1 therapy, and successfully managed with injectable formula orally for about 5 months. Oral administration of injectable vitamin K1 might be a suitable substitute for intravenous route in long-term treatment for LAAR poisonings.

Local Cytotoxic Effects in Cobra Envenoming: A Pilot Study.

The cobra (genus Naja (N.)) is one of the most common venomous snakes. Due to its frequency and deadly complications of muscle paralysis, local necrosis, and chronic musculoskeletal disability, it should not be ignored. The pathology of devastating tissue destruction, even though specific antivenoms exist, is not fully clear. Here, we attempted to dig in envenomed tissues to study the clinical toxicology of cobra venom. Four cases of N. atra snake envenomation, in which the subjects developed advanced tissue injury, were involved in this study. We used enzyme-ligand sandwich immunoassay (ELISA) to assay the whole venom, cytotoxin A3 and short-chain neurotoxin (sNTX) in blood, bullae, wound discharge, and debrided tissue. We found that persistently high concentrations of venom and toxins, especially cytotoxin A3, were detected in bullae, wound discharge fluid and necrotic tissue of these patients even after large doses of specific antivenom treatment, and wide excision and advanced debridement could largely remove these toxins, lessen the size of necrosis, and promote wound healing. We also found that the point-of-care apparatus, ICT-Cobra kit, might be used to promptly monitor the wound condition and as one of the indicators of surgical intervention in cases of cobra envenomation in Taiwan.

Clinical and molecular genetic analysis of a Chinese family with hereditary elliptocytosis caused by a novel mutation in the EPB41 gene.

BACKGROUND: Hereditary elliptocytosis (HE) is a heterogeneous red blood cell membrane disorder characterized by the presence of elliptocytes on a peripheral blood smear. Clinical manifestations of HE vary widely from asymptomatic carriers to patients with severe transfusion-dependent anemia. Most patients are asymptomatic or have mild anemia, which hinders diagnosis. The proband in this case had mild anemia and jaundice over a period of 4 years, the etiology of which was unclear. Hence, he was admitted to our hospital for further diagnosis. METHODS: Peripheral blood smears and routine blood tests were performed and biochemical parameters of the proband, and his family members were determined. To confirm the diagnosis, gene mutations were screened in the proband using next-generation sequencing (NGS) and verified by Sanger sequencing in other family members. RESULTS: A novel mutation (c.1294delA, p.Ser432 fs) in exon 15 of the EPB41 gene was detected in the proband and his family members. This mutation results in a frameshift and a premature stop codon at position 455, encoding a truncated protein. The variant was likely pathogenic according to the criteria of the American College of Medical Genetics and Genomics. SWISS-MODEL protein structure prediction indicated partial loss of the spectrin and actin binding and C-terminal domains. CONCLUSION: A heterozygous mutation 1294delA in exon 15 of the EPB41 gene was identified using NGS and Sanger sequencing in members of a Chinese family. This identification expands the spectrum of EPB41 mutations and contributes to the genetic diagnosis of families with HE.

Collocation of avian and mammal antibodies to develop a rapid and sensitive diagnostic tool for Russell's Vipers Snakebite.

Russell's vipers (RVs) envenoming is an important public health issue in South-East Asia. Disseminated intravascular coagulopathy, systemic bleeding, hemolysis, and acute renal injury are obvious problems that develop in most cases, and neuromuscular junction blocks are an additional problem caused by western RV snakebite. The complex presentations usually are an obstacle to early diagnosis and antivenom administration. Here, we tried to produce highly specific antibodies in goose yolks for use in a paper-based microfluidic diagnostic kit, immunochromatographic test of viper (ICT-Viper), to distinguish RVs from other vipers and even cobra snakebite in Asia. We used indirect ELISA to monitor specific goose IgY production and western blotting to illustrate the interaction of avian or mammal antibody with venom proteins. The ICT-Viper was tested not only in prepared samples but also in stored patient serum to demonstrate its preliminary efficacy. The results revealed that specific anti-Daboia russelii IgY could be raised in goose eggs effectively without inducing adverse effects. When it was collocated with horse anti-Daboia siamensis antibody, which broadly reacted with most of the venom proteins of both types of Russell's viper, the false cross-reactivity was reduced, and the test showed good performance. The limit of detection was reduced to 10 ng/ml in vitro, and the test showed good detection ability in clinical snake envenoming case samples. The ICT-Viper performed well and could be combined with a cobra venom detection kit (ICT-Cobra) to create a multiple detection strip (ICT-VC), which broadens its applications while maintaining its detection ability for snake envenomation identification. Nonetheless, the use of the ICT-Viper in the South-East Asia region is pending additional laboratory and field investigations and regional collaboration. We believe that the development of this practical diagnostic tool marks the beginning of positive efforts to face the global snakebite issue.

A Rapid and International Applicable Diagnostic Device for Cobra (Genus Naja) Snakebites.

Cobra snakes (genus Naja) are some of the most dangerous snake species in Asia and Africa, as their bites cause severe life-threatening respiratory failure and local tissue destruction, especially in the case of late diagnosis. The differential diagnosis of snakebite envenomation still mainly relies upon symptomatology, the patient's description, and the experience of physicians. We have designed a rapid test, immunochromatographic test of cobra (ICT-Cobra), which obtained fair results in improving the diagnosis and treatment of Naja (N.) atra snakebites in Taiwan. In this study, we further investigated the feasibility of applying the kit for the detection of other cobra venoms based on the potential interspecies similarity. We firstly demonstrated the cross-reactivity between eight venoms of medically important cobra species and the rabbit anti-N. atra IgG that was used in ICT-Cobra by Western blotting and sandwich enzyme-linked immunosorbent assay. Then, ICT-Cobra was used to detect various concentrations of the eight venoms to elucidate its performance. Noticeable correlations between the cross-reactivity of venoms from genus Naja snakes and existing geographical characteristics were found. ICT-Cobra could detect venoms from other Asian cobras with variable detection limits comparable to those observed for N. atra, but the kit was less successful in the detection of venom from African cobras. The similar but slightly different venom components and the interaction between venom and rabbit anti-N. atra IgG led to variations in the detection limits. The transcontinental usage of ICT-Cobra might be possible due to the cross-reactivity of antibodies and similarities among the larger-sized proteins. This study showed that the close immunological relationships in the genus Naja could be used to develop a venom detection kit for the diagnosis of cobra envenomation in both Asian and African regions. Additional clinical studies and technical adjustments are still needed to improve the efficacy and broadening the application of ICT-Cobra in the future.

Alignment of Cell Lineage Trees Elucidates Genetic Programs for the Development and Evolution of Cell Types.

A full understanding of the developmental process requires fine-scale characterization of cell divisions and cell types, which are naturally organized as the developmental cell lineage tree (CLT). Technological breakthroughs facilitated determination of more CLTs, but complete comprehension of the data remains difficult without quantitative comparison among CLTs. We hereby quantified phenotypic similarity between CLTs using a novel computational method that exhaustively searches for optimal correspondence between individual cells meanwhile retaining their topological relationships. The revealed CLT similarities allowed us to infer functional similarity at the transcriptome level, identify cell fate transformations, predict functional relationships between mutants, and find evolutionary correspondence between cell types of different species. By allowing quantitative comparison between CLTs, our work is expected to greatly enhance the interpretability of relevant data and help answer the myriad of questions surrounding the developmental process.

Patients with Gastric Polyps need Colonoscopy Screening at Younger Age: A Large Prospective Cross-Sectional Study in China.

Background To date, it is not clarified whether patients with gastric polyps without any alarming symptoms for colorectal neoplasia need colonoscopy screening. The objective of this study is to prospectively determine the association between gastric polyps and colorectal neoplasia. Methods A multicenter prospective cross-sectional study was performed from July 2012 to December 2014. We compared patients with and without gastric polyps for prevalence of colorectal adenomas. The odds ratios (OR) were computed by logistic regression analysis after multivariable adjustments. Results Totally 1546 patients were included, with 770 patients in the gastric polyp group and 776 in the age- and sex- matched control group. Patients with gastric polyps had greater odds of having any colorectal adenoma (adjusted OR=2.34, 95% confidence interval [CI]: 1.79 to 3.06, p<0.001) and advanced colorectal adenomas (adjusted OR=2.71, 95% CI: 1.74 to 4.23, p<0.001) than those without. The positive association between gastric polyps and colorectal adenomas remained significant in both women (OR=2.34, 95% CI: 1.66 to 3.29, p<0.001) and men (OR=1.87, 95% CI: 1.31 to 2.66, p=0.001). Patients over the age of 40 with gastric polyps had a higher prevalence of colorectal adenomas than those without (40-49yr: OR=1.81, 95% CI=1.02-3.21, p=0.04; 50-59yr: OR=1.88, 95% CI=1.26-2.81, p<0.001; 60-74yr: OR=2.62, 95% CI=1.73-3.98, p<0.001). Conclusions The presence of gastric polyps is significantly associated with a higher prevalence of colorectal adenomas, especially advanced colorectal adenomas. Colonoscopy might be considered in patients with gastric polyps, of any gender, and over the age of 40.

Continuous Near-Field Electrospraying Using a Glass Capillary Nozzle.

A continuous near-field electrospray process has been developed to deposit micropatterns. Different from traditional electrospray technologies, the nozzle-to-substrate distance was shortened to less than 5 mm, and a glass capillary nozzle with a diameter of tens of microns was used. Steady and continuous ejection was achieved, and patterns with line widths of sub-100 µm were generated. The influence of experimental parameters was investigated. The critical voltage for electrospray increased with nozzle-to-substrate distance and flow rate. The line width of electrosprayed patterns increased with the increases in applied voltage, flow rate, nozzle diameter, and deposition time. This work provides a simple and potential route for on-demand deposition of micro-/nano-patterns in the electrospray process.

Electrospray Deposition of ZnO Thin Films and Its Application to Gas Sensors.

Electrospray is a simple and cost-effective method to fabricate micro-structured thin films. This work investigates the electrospray process of ZnO patterns. The effects of experimental parameters on jet characteristics and electrosprayed patterns are studied. The length of stable jets increases with increasing applied voltage and flow rate, and decreases with increasing nozzle-to-substrate distance, while electrospray angles exhibit an opposite trend with respect to the stable jet lengths. The diameter of electrosprayed particles decreases with increasing applied voltage, and increases with flow rate. Furthermore, an alcohol gas sensor is presented. The ZnAc is calcined into ZnO, which reveals good repeatability and stability of response in target gas. The sensing response, defined as the resistance ratio of R0/Rg, where R0 and Rg are resistance of ZnO in air and alcohol gas, increases with the concentration of alcohol vapors and electrospray deposition time.

Hepcidin expression in anemia of chronic disease and concomitant iron-deficiency anemia.

Hepcidin is a key hormone governing mammalian iron homeostasis and may be directly or indirectly involved in the development of most iron deficiency/overload and inflammation-induced anemia. The objective of this study was to investigate the expression of hepcidin in anemia of chronic disease. To characterize serum hepcidin, iron and inflammatory indicators associated with anemia of chronic disease (ACD), we studied ACD, ACD concomitant iron-deficiency anemia (ACD/IDA), pure IDA and acute inflammation (AcI) patients and analyzed the associations between hepcidin levels and inflammation parameters in various types of anemia. Serum hepcidin levels in patient groups were statistically different, from high to low: ACD, AcI > ACD/IDA > the control > IDA. Serum ferritin levels were significantly increased in ACD and AcI patients but were decreased significantly in ACD/IDA and IDA. Elevated serum EPO concentrations were found in ACD, ACD/IDA and IDA patients but not in AcI patients and the controls. A positive correlation between hepcidin and IL-6 levels only existed in ACD/IDA, AcI and the control groups. A positive correlation between hepcidin and ferritin was marked in the control group, while a negative correlation between hepcidin and ferritin was noted in IDA. The significant negative correlation between hepcidin expression and reticulocyte count was marked in both ACD/IDA and IDA groups. All of these data demonstrated that hepcidin might play role in pathogenesis of ACD, ACD/IDA and IDA, and it could be a potential marker for detection and differentiation of these anemias.

Combination treatment with arsenic trioxide and irradiation enhances cell-killing effects in human fibrosarcoma cells in vitro and in vivo through induction of both autophagy and apoptosis.

The traditional treatments for fibrosarcoma have limited efficacy. Therefore, new therapeutic strategies and/or new adjuvant drugs still need to be explored. Accumulating evidence indicates that programmed cell death (PCD) is closely related to anticancer therapy. Many studies have shown that tumor cells treated with anticancer drugs experience the induction of type I PCD, apoptosis, and type II PCD, autophagy. In the present study, we investigated the anticancer effects of ionizing radiation (IR) combined with arsenic trioxide (ATO) in human fibrosarcoma cells in vitro and in xenograft tumors in SCID mice in vivo. We found that IR increased the population of HT1080 cells in the G2/M phase in a time-dependent manner within 9 h. IR treatment combined with ATO at this time point induced a significantly prolonged G2/M arrest and consequently enhanced cell death. Furthermore, damage of mitochondria membrane potential could be involved in the underlying mechanisms. The enhanced cytotoxic effect of combined treatment occurred due to the increased induction of more autophagy and apoptosis through the inhibition of Akt and the activation of ERK1/2 signaling pathways in HT1080 cells. The combined treatment of HT1080 cells pretreated with Z-VAD or 3-MA resulted in a significant reduction in AO-positive cells, apoptotic cells and cytotoxicity. In in vivo studies, the combination of IR and ATO significantly reduced the tumor volume in SCID mice that had received a subcutaneous injection of HT1080 cells. The data suggest that a combination of IR and ATO could be a new potential therapeutic strategy for the treatment of fibrosarcoma.

Lycorine induces apoptosis and down-regulation of Mcl-1 in human leukemia cells.

Lycorine is an alkaloid isolated from the bulb of the Amaryllidaceae Lycoris. Here, we report that treatment with lycorine resulted in survival inhibition and apoptosis induction in human leukemia cell lines. Lycorine induced apoptosis in human leukemia cells via intrinsic mitochondria pathway and caused a rapid-turnover of protein level of Mcl-1 which occurred before caspases activation. Furthermore, pronounced apoptosis accompanied by the down-regulation of Mcl-1 was also observed in blasts from patients with acute myeloid leukemia. Our findings suggest that lycorine may be a good candidate therapeutic agent against leukemia in worth of further evaluation.

Matrine-induced apoptosis in leukemia U937 cells: involvement of caspases activation and MAPK-independent pathways.

It is reported that matrine, one of the major effective compounds isolated from the root of Sophora flavescens Ait., has anti-leukemia activity. In this study, we find that the treatment of leukemia U937 cells with matrine results in induction of apoptosis. Analysis of the mechanism underling this apoptotic event showed activation of caspases-9, -3, and -7, and release of cytochrome C from mitochondria to cytosol, and cleavage of poly(ADP-ribose) polymerase. Matrine did not alter the level of bcl-2 and bcl-xL as well as bax. In addition, no correlation was found between matrine administration and activation of the three major MAPK subfamilies (Erk1/2, p38, JNK/SAPK). The results indicate that matrine induces apoptosis in U937 cells via a cytochrome C-triggered caspase activation pathway.