Age and seasonal variation and establishment of reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry.

OBJECTIVES: We aimed to establish reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry to improve the diagnosis of vitamin deficiency and outcomes of associated conditions. METHODS: In this retrospective analysis of 24 810 specimens, we aimed to examine sex-, age-, and season-related variations in vitamin levels in different groups, set reference-value intervals for vitamin levels, and evaluate these reference values against those recommended by manufacturers. RESULTS: Levels of vitamins B3, B5, B6, B7, and B12 were higher, and those of vitamins B2, B9, and C were lower, in men than in women. There were seasonal variations in levels of vitamins B1, B3, B5, B6, B9, B12, and C. Levels of vitamins B1, B2, B3, B5, B6, B7, B9, and C differed across age groups; vitamin B1 displayed significant differences between ages 0 to 14 years and adults compared with reference change values. The lower limits of vitamins B1 (ages 15-100 y), B2, B3, B7, and C were lower, and that of vitamin B5 was higher, than the recommended reference values. Finally, the upper limits of vitamins B1, B3, B5, B6, and B7 were lower than the recommended values. CONCLUSIONS: For values obtained using liquid chromatography tandem mass spectrometry, the lower limits of reference intervals for vitamins B1 (ages 15-100 y), B2, B3, B7, and C should be lowered, that of vitamin B5 should be raised, and the upper limits of reference intervals for vitamins B1, B3, B5, B6, and B7 should be lowered.

Analysis of pathogenic bacteria distribution and drug resistance characteristics of bloodstream infection in patients with neutrophilic deficiency after chemotherapy in acute leukemia / 中国热带医学

@#Abstract: Objective　To investigate the distribution and drug resistance characteristics of pathogenic bacteria in patients with neutropenic acute leukemia (AL) and bloodstream infections (BSI). Methods　The clinical data of 258 neutropenic acute leukemia patients with bloodstream infections, who admitted to Shengjing Hospital of China Medical University from January 2016 to December 2021, were collected and analyzed for pathogenic bacteria and drug resistance. Results A total of 268 strains of pathogenic bacteria were isolated from 258 patients, including 180 strains of gram-negative bacteria (67.16%), 61 strains of gram-positive bacteria (22.76%), and 27 strains of fungi (10.07%). Gram-negative bacteria were mainly Klebsiella pneumoniae (53/268, 19.78%), Escherichia coli (49/268, 18.28%) and Pseudomonas aeruginosa (41/268, 15.30%). Gram-positive bacteria were mainly coagulase negative Staphylococcus (31/268, 11.57%) and Staphylococcus aureus(17/268, 6.34%). The main fungi were Candida tropicalis (25/268, 9.33%). Escherichia coli (33/268, 12.31%) was the most common pathogen isolated from acute myeloid leukemia (AML), followed by Pseudomonas aeruginosa (25/268, 9.33%), coagulase-negative Staphylococcus (18/268, 6.72%) and Candida tropicalis (18/268, 6.72%). Klebsiella pneumoniae (35/268, 13.06%) was the most common pathogen isolated from acute lymphoblastic leukemia (ALL),followed by Pseudomonas aeruginosa (15/268, 5.60%) and Escherichia coli (14/268, 5.22%). The resistance of Gram-negative bacteria to piperacillin/tazobactam, cefoperazone/sulbactam, imipenem, meropenem, ertapenem, amikacin, cefoxitin, amoxicillin/clavulanic acid was low. Gram-positive bacteria were sensitive to linezolid and vancomycin. Candida was sensitive to flucytosine, amphotericin B and itraconazole. Conclusions　In patients with granulosa after AL chemotherapy combined with BSI, the pathogenic bacteria isolated from AML are diverse, and the pathogenic bacteria isolated from ALL are mainly gram-negative bacteria. Pathogenic bacteria have different degrees of drug resistance to commonly used antibacterial drugs, so it is important to strengthen the monitoring of the distribution of pathogenic bacteria and the change of drug resistance and rational use of antibacterial drugs to minimize the death of patients.

Hypofibrinogenemia Caused by Hemocoagulase Injection: A Retrospective Study on Clinical Laboratory Findings.

Objective Hemocoagulase injection based on the venom of Agkistrodon halys Pallas is widely used in the treatment of hemorrhagic disorders. This study aimed to characterize the clinical laboratory findings of hemocoagulase-induced hypofibrinogenemia as the associated adverse reaction of hemocoagulase injection.Methods We retrospectively enrolled 27 in-patients who were treated with hemocoagulase injection for hemoptysis and developed hypofibrinogenemia during the period of January 1, 2015 to March 31, 2018. Clinical data were collected and investigated, including clinical manifestations, hemostatic and fibrinolytic parameters, dosage of hemocoagulase, the medication time, and the cryoprecipitate blood product infusion. Differences in fibrinogen, D-dimer, and fibrin/fibrinogen degradation products (FDP) before, during, and after the application of hemocoagulase injection were analyzed statistically.Results Plasma fibrinogen level during medication of hemocoagulase injection decreased significantly compared to that before the treatment (F=1.80, P<0.001), with the average decrease of 2.28 g/L (0.63-3.9 g/L). After withdrawal, fibrinogen level increased significantly compared to that during the medication (F=-1.20, P<0.001), but was still lower than that before the medication (F=0.59, P=0.03). The D-dimer level and the FDP level after withdrawal decreased significantly compared to the levels during the medication (F=0.83, P=0.002; Wilcoxon-test, Z=-4.54, P<0.001). Spearman's correlation analyses did not find either fibrinogen change during-before the administration or FDP change after-during the administration was associated with the dosage of hemocoagulase (r=-0.17, P=0.40; r=-0.28, P=0.15; respectively) and the time of recovery from hypofibrinogenemia (r=-0.45, P=0.05; r=0.13, P=0.61; respectively).Conclusion Monitoring both clotting and fibrinolysis parameters is essential in the management of hemoptysis patients treated with hemocoagulase injection. Clinicians should be aware of hypofibrinogenemia and consider discontinuation of the administration of hemocoagulase whenever necessary.

Modulation of anti-malaria immunity by vitamin A in C57BL/6J mice infected with heterogenic plasmodium.

Vitamin A (VA) is an anti-inflammatory agent that is important in modulating and balancing the immune system. The present study aimed to investigate the immunoregulatory effects of vitamin A supplement (VAS) in C57BL/6J mice infected with Plasmodium yoelii 17XL (P.y17XL) or Plasmodium berghei ANKA (P.bANKA). Following VA treatment, parasitaemia decreased, but survival rate did not significantly change during P.y17XL infection. However, in P.bANKA infected C57BL/6J mice, VA pretreatment decreased parasitaemia, and a lag in cerebral malaria (CM) was observed during the early stages of infection. Furthermore, VA pretreatment was also demonstrated to upregulate MHCII expression in dendritic cells (DCs), downregulate Th1 and Tregs, and downregulate TNF-α and IFN-γ production. The results of the current study indicated that VAS downregulated the inflammation response in CM, but did not exhibit an immunoregulatory effect against P.y17XL infection. VAS protected the onset of CM by reducing inflammation, and was also correlated with the downregulation of Th1 by modifying the function of DCs and Tregs. However, no significant effect was observed during P.y17XL infection.

[An analysis of GNAS and THRA gene mutations in children with congenital hypothyroidism].

OBJECTIVE: To preliminarily investigate the relationship between stimulatory G protein α subunit (GNAS) and thyroid hormone receptor α (THRA) gene mutations and clinical phenotypes in children with congenital hypothyroidism (CH). METHODS: A total of 70 children with CH diagnosed by neonatal screening were enrolled. Their peripheral blood samples were collected to extract genomic DNA. GNAS and THRA genes were screened for mutations using next-generation sequencing. Bioinformatics software was used to analyze the pathogenicity of gene mutations. RESULTS: Of the 70 children with CH, nine missense mutations (three known mutations and six novel mutations) in the GNAS gene were detected in three patients (4%), and one gene polymorphism, c.508A>G(p.I170V), in the THRA gene was detected in four patients. The analysis results of bioinformatics software and ACMG/AMP guidelines showed that the two GNAS gene mutations [c.301C>T(p.R101C) and c.334G>A(p.E112K)] were more likely to be pathogenic. Three children with GNAS gene mutations showed different degrees of hypothyroidism. CONCLUSIONS: GNAS gene mutations are related to the development of CH, and children with CH have different clinical manifestations. THRA gene mutations may not be associated with CH.

[Advances in genetic research of congenital hypothyroidism in China].

Congenital hypothyroidism (CH), which results from insufficient thyroid hormone biosynthesis, is one of the most common neonatal endocrine disorders. Thyroid dysgenesis and thyroid dyshormonogenesis are the two causes of CH and either one will lead to deficiencies of enzymes during thyroid hormone biosynthesis and insufficient thyroid hormone biosynthesis. Recently, researchers have performed extensive studies on genetics of CH. This paper reviews genes reported to be associated with CH in China.

Variants in the Promoter Region of HLA-DQA1 were Associated with Idiopathic Membranous Nephropathy in a Chinese Han Population.

BACKGROUND: Idiopathic membranous nephropathy (IMN) is an autoimmune disease and the leading cause of adult nephritic syndrome. HLA-DQA1 had been identified to be associated with IMN in Europeans and the result was replicated in Chinese Han population. In this study, six single nucleotide polymorphisms (SNPs) in the promoter of HLA-DQA1 and other two SNPs with IgA nephropathy were included for the association analysis. METHODS: The SNPs were genotyped in 509 patients and 601 controls by the MassArray iPLEX. The quantification of anti-phospholipase A2 receptor (PLA2R) antibodies in sera of IMN patients was performed by anti-PLA2R ELISA (IgG) kit. RESULTS: After analysis, four SNPs were significantly associated with IMN, with rs2187668 and rs28383345 as the top two signals (P = 8.42×10-5 and 2.48×10-5, respectively). Even under dominant model, the two SNPs were still significantly associated with IMN (P = 3.50×10-3 for rs28383345 and P = 6.55×10-5 for rs2187668). After conditional study with rs2187668, rs28383345 was the only variant significantly correlated with IMN after Bonferroni correction (P = 0.016). The minor alleles of the two SNPs were also mutually exclusive in our cohort. This indicated that the two SNPs were independently associated with IMN in Chinese Han population. Levels of anti-PLA2R autoantibodies were correlated with the genotypes of the two SNPs, but not significantly (P>0.05). CONCLUSIONS: Our results revealed that a novel independent variant in the promoter of HLA-DQA1 was associated with IMN in Chinese Han population. The locus possessed regulatory role according to the data of RegulomeDB. The exact role of the SNPs on the expression of HLA-DQA1 needs further investigation.

DBD-F induces apoptosis in gastric cancer-derived cells through suppressing HIF2α expression.

PURPOSE: Gastric cancer is the third leading cause of cancer-related death in China. Accumulating evidence indicates that HIF2α may affect the aggressiveness of gastric cancer. It has also been found that HIF2α C-terminal PAS domains can form complexes with inactive benzoxadiazole antagonists. Here, the anti-tumor effect of 4-(N,Ndimethylaminosulphonyl)-7-fluoro-1,2,3-benzoxadiazole (DBD-F) on human gastric cancer cells was examined using both in vitro and in vivo assays. METHODS AND RESULTS: We found that DBD-F can induce apoptosis and inhibit the mobility of MKN28 and MKN45 gastric cancer-derived cells in vitro. We also found that DBD-F can suppress tumor growth in established gastric cancer-derived xenograft models in vivo. Finally, we found that DBD-F can inhibit HIF2α expression in gastric cancer-derived cells. CONCLUSIONS: From our findings we conclude that DBD-F (i) is cytotoxic to gastric cancer-derived cells and (ii) can induce apoptosis in these cells via the MEK/ERK signaling pathway. In addition, our findings strongly indicate that DBD-F can inhibit HIF2α expression by affecting the phosphorylation status of MEK/ERK in gastric cancer-derived cells.

Phosphorylation of nephrin triggers its internalization by raft-mediated endocytosis.

Proper localization of nephrin determines integrity of the glomerular slit diaphragm. Slit diaphragm proteins assemble into functional signaling complexes on a raft-based platform, but how the trafficking of these proteins coordinates with their signaling function is unknown. Here, we demonstrate that a raft-mediated endocytic (RME) pathway internalizes nephrin. Nephrin internalization was slower with raft-mediated endocytosis than with classic clathrin-mediated endocytosis. Ultrastructurally, the RME pathway consisted of noncoated invaginations and was dependent on cholesterol and dynamin. Nephrin constituted a stable, signaling-competent microdomain through interaction with Fyn, a Src kinase, and podocin, a scaffold protein. Tyrosine phosphorylation of nephrin triggered its own RME-mediated internalization. Protamine-induced hyperphosphorylation of nephrin led to noncoated invaginations predominating over coated pits. These results demonstrate that an RME pathway couples nephrin internalization to its own signaling, suggesting that RME promotes proper spatiotemporal assembly of slit diaphragms during podocyte development or injury.

Predisposition to relapsing nephrotic syndrome by a nephrin mutation that interferes with assembly of functioning microdomains.

Minimal-change disease (MCD) is the most common cause of nephrotic syndrome (NS) and is characterized only by minor morphological alterations in podocytes. A subtype of MCD arises from mutations in nephrin, a major component of the slit diaphragm (SD). Idiopathic MCD is a complex trait where interactions of genetic and immunological factors are implicated. However, the pathogenic mechanisms remain unclear. Here we studied the molecular basis for familial NS characterized by frequent relapses and minimal-change histology. Our previous mutational analysis revealed that the two affected children were compound heterozygotes for nephrin variants C265R and V822M (Kidney Int., 2008). When heterologously expressed, these variants exhibited normal metabolic half-life and raft binding. C265R exhibited substantial ER retention, reflecting an intracellular trafficking defect. In contrast, V822M was able to reach the plasma membrane, but was restricted in lateral diffusion as well as trafficking at the cell surface. Clustering of V822M failed to evoke a maximum tyrosine-phosphorylation and actin reorganization, suggesting the inability to assemble into functioning membrane microdomains. Our results suggest that C265R and V822M compose a dysfunctional SD complex due to their mixed defects comprising reduced cell surface targeting and ineffective assembly of signaling microdomains. The defective SD likely confers a susceptibility to immunogenic stimuli and predisposes to a relapsing phenotype.

Podocin participates in the assembly of tight junctions between foot processes in nephrotic podocytes.

The predominant type of cellular junction between normal podocyte foot processes is the slit diaphragm. Under nephrotic conditions,however, foot process effacement leads to the loss of slit diaphragms and the new formationof tight junctions composed of the proteins coxsackievirus and adenovirus receptor (CAR) and zonula occludens 1 (ZO-1). Podocin, a protein that plays a key role in maintaining the integrity of the slit diaphragm, has also been localized to these tight junctions, but its function at this site is unknown. In this study, we confirmed that podocin colocalizes with CAR and ZO-1 at the tight junction between foot processes in nephrotic rats. Using primary cultures of rat podocytes, as well as cell lines that co-expressed podocin and CAR, we observed that podocin was recruited to sites of cell-cell contact and that it co-localized with CAR and ZO-1. Immunoprecipitation suggested that these three junctional proteins from a multi-protein complex. Consistent with this, we found that podociin facilitated the coalescence of preassembled lipid rafts containing CAR and restricted their lateral mobility, the latter likely a result of dynamic actin reorganization and subsequent tethering of CAR-podocin complexes to the cytoskeleton. In conclusion, in addition to serving as a structural protein of the slit diaphragm of normal podocytes, our data suggest that podocin may also serve as a scaffold that links tight junction proteins to the actin cytoskeleton in nephrotic foot processes.

Effects of extract of Ginkgo biloba with venlafaxine on brain injury in a rat model of depression.

BACKGROUND: Recent studies have indicated that chronic stress may give rise to brain damage, which is related to the genesis of depression. The purpose of this study is to investigate the effects of extract of Ginkgo biloba (EGb) and venlafaxine on depression. METHODS: Rats were treated with chronic and comprehensive stress to create a depression model. Immunohistochemistry was used to detect the expression of brain-derived neurotrophic factor (BDNF) in the hippocampal CA3 neurons of rats treated with different drugs. Behavioral changes of these rats were also examined. RESULTS: The expression of BDNF in the hippocampal CA3 neurons of the depression model decreased with a reduction in exploring behavior and a significant increase in fecal production. The expression of neuron nitric-oxide synthase (nNOS) protein also increased in the rats compared to normal controls. The rats treated with EGb and venlafaxine showed an increase in expression of BDNF and exploring behavior compared to untreated rats, but a decrease in nNOS and fecal production. CONCLUSIONS: Rats sustain damage to the brain after being subjected to chronic and comprehensive stress. Our research has indicated that combined EGb with venlafaxine enhances the protection of neurons and decreases damage to the brain, while relieving the side effects of synthetic antidepressants.