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1.
Nat Commun ; 15(1): 7342, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187496

RESUMO

Acetylcholine regulates various cognitive functions through broad cholinergic innervation. However, specific cholinergic subpopulations, circuits and molecular mechanisms underlying recognition memory remain largely unknown. Here we show that Ngfr+ cholinergic neurons in the substantia innominate (SI)/nucleus basalis of Meynert (nBM)-medial prefrontal cortex (mPFC) circuit selectively underlies recency judgements. Loss of nerve growth factor receptor (Ngfr-/- mice) reduced the excitability of cholinergic neurons in the SI/nBM-mPFC circuit but not in the medial septum (MS)-hippocampus pathway, and impaired temporal order memory but not novel object and object location recognition. Expression of Ngfr in Ngfr-/- SI/nBM restored defected temporal order memory. Fiber photometry revealed that acetylcholine release in mPFC not only predicted object encounters but also mediated recency judgments of objects, and such acetylcholine release was absent in Ngfr-/- mPFC. Chemogenetic and optogenetic inhibition of SI/nBM projection to mPFC in ChAT-Cre mice diminished mPFC acetylcholine release and deteriorated temporal order recognition. Impaired cholinergic activity led to a depolarizing shift of GABAergic inputs to mPFC pyramidal neurons, due to disturbed KCC2-mediated chloride gradients. Finally, potentiation of acetylcholine signaling upregulated KCC2 levels, restored GABAergic driving force and rescued temporal order recognition deficits in Ngfr-/- mice. Thus, NGFR-dependent SI/nBM-mPFC cholinergic circuit underlies temporal order recognition memory.


Assuntos
Acetilcolina , Neurônios Colinérgicos , Córtex Pré-Frontal , Animais , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiologia , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/fisiologia , Acetilcolina/metabolismo , Camundongos , Masculino , Camundongos Knockout , Reconhecimento Psicológico/fisiologia , Núcleo Basal de Meynert/metabolismo , Núcleo Basal de Meynert/fisiologia , Camundongos Endogâmicos C57BL , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Hipocampo/metabolismo , Receptores de Fator de Crescimento Neural
2.
Mol Psychiatry ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762692

RESUMO

Autism Spectrum Disorders (ASD) comprise a range of early age-onset neurodevelopment disorders with genetic heterogeneity. Most ASD related genes are involved in synaptic function, which is regulated by mature brain-derived neurotrophic factor (mBDNF) and its precursor proBDNF in a diametrically opposite manner: proBDNF inhibits while mBDNF potentiates synapses. Here we generated a knock-in mouse line (BDNFmet/leu) in which the conversion of proBDNF to mBDNF is attenuated. Biochemical experiments revealed residual mBDNF but excessive proBDNF in the brain. Similar to other ASD mouse models, the BDNFmet/leu mice showed reduced dendritic arborization, altered spines, and impaired synaptic transmission and plasticity in the hippocampus. They also exhibited ASD-like phenotypes, including stereotypical behaviors and deficits in social interaction. Moreover, the plasma proBDNF/mBDNF ratio was significantly increased in ASD patients compared to normal children in a case-control study. Thus, deficits in proBDNF to mBDNF conversion in the brain may contribute to ASD-like behaviors, and plasma proBDNF/mBDNF ratio may be a potential biomarker for ASD.

4.
MedComm (2020) ; 5(5): e532, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38645663

RESUMO

Alzheimer's disease (AD) constitutes a neurodegenerative disorder marked by a progressive decline in cognitive function and memory capacity. The accurate diagnosis of this condition predominantly relies on cerebrospinal fluid (CSF) markers, notwithstanding the associated burdens of pain and substantial financial costs endured by patients. This study encompasses subjects exhibiting varying degrees of cognitive impairment, encompassing individuals with subjective cognitive decline, mild cognitive impairment, and dementia, constituting a total sample size of 82 participants. The primary objective of this investigation is to explore the relationships among brain atrophy measurements derived from magnetic resonance imaging, atypical electroencephalography (EEG) patterns, behavioral assessment scales, and amyloid ß-protein (Aß) indicators. The findings of this research reveal that individuals displaying reduced Aß1-42/Aß-40 levels exhibit significant atrophy in the frontotemporal lobe, alongside irregularities in various parameters related to EEG frequency characteristics, signal complexity, inter-regional information exchange, and microstates. The study additionally endeavors to estimate Aß1-42/Aß-40 content through the application of a random forest algorithm, amalgamating structural data, electrophysiological features, and clinical scales, achieving a remarkable predictive precision of 91.6%. In summary, this study proposes a cost-effective methodology for acquiring CSF markers, thereby offering a valuable tool for the early detection of AD.

5.
NPJ Aging ; 10(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167843

RESUMO

One critical manifestation of neurological deterioration is the sign of cognitive decline. Causes of cognitive decline include but are not limited to: aging, cerebrovascular disease, Alzheimer's disease, and trauma. Currently, the primary tool used to examine cognitive decline is scale. However, scale examination has drawbacks such as its clinician subjectivity and inconsistent results. This study attempted to use resting-state EEG to construct a cognitive assessment model that is capable of providing a more scientific and robust evaluation on cognition levels. In this study, 75 healthy subjects, 99 patients with Mild Cognitive Impairment (MCI), and 78 patients with dementia were involved. Their resting-state EEG signals were collected twice, and the recording devices varied. By matching these EEG and traditional scale results, the proposed cognition assessment model was trained based on Adaptive Boosting (AdaBoost) and Support Vector Machines (SVM) methods, mapping subjects' cognitive levels to a 0-100 test score with a mean error of 4.82 (<5%). This study is the first to establish a continuous evaluation model of cognitive decline on a large sample dataset. Its cross-device usability also suggests universality and robustness of this EEG model, offering a more reliable and affordable way to assess cognitive decline for clinical diagnosis and treatment as well. Furthermore, the interpretability of features involved may further contribute to the early diagnosis and superior treatment evaluation of Alzheimer's disease.

6.
Basic & Clinical Medicine ; (12): 548-552, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1018653

RESUMO

Pulmonary fibrosis is a progressive interstitial fibrotic lung disease with high mortality.Its pathogenesis is complex and involves the reprogramming of fatty acid metabolism.This reprogramming includes changes in de novo fatty acid synthesis,uptake,oxidation,and derivatives.It crucially influences alveolar epithelial cell survival,macrophage polarization,and fibroblast activation,thereby playing a significant role in either exacerbating or miti-gating the disease.Understanding and intervening in the reprogramming of fatty acid metabolism offers potential strategies for prevention,diagnosing and treatment of pulmonary fibrosis.

7.
China Pharmacy ; (12): 1327-1333, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1031708

RESUMO

OBJECTIVE To investigate the effects of Taohong siwu decoction modified granules on podocyte epithelial- mesenchymal-transition (EMT) and renal fibrosis in diabetic kidney disease (DKD) model rats. METHODS Eight rats were selected as normal group (ordinary feed); the remaining rats were given a high-glucose and high-fat diet combined with intraperitoneal injection of streptozotocin (35 mg/kg) to induce the DKD model. Model rats were randomly divided into model group, irbesartan group [positive control, 13.5 mg/(kg·d)] and modified Taohong siwu decoction group [6.48 g/(kg·d)], with 8 rats in each group. All groups were given relevant medicine intragastrically, once a day, for 16 consecutive weeks. Twenty-four- hour urinary total protein (24 h UTP) was detected at the end of the 4th, 8th, 12th and 16th week of administration. After the last medication, the body mass, water intake, food intake, urine output, the levels of fasting blood glucose, serum creatinine (Scr) and blood urea nitrogen (BUN) as well as mRNA and protein expressions of P-cadherin, nephrin, α -smooth muscle actin (α-SMA), Wilms’ tumor gene 1 (WT1), transforming growth factor-β1( TGF-β1) and type Ⅳ collagen (Col-Ⅳ) in renal tissue were determined. The pathological and morphological changes in renal tissue were observed and the thickness of the glomerular basement membrane was determined. RESULTS Compared with the model group, 24 h UTP of rats was significantly decreased in modified Taohong siwu decoction group since the 8th weekend (P<0.05); the body weight of rats increased significantly, but the amount of water intake and urine decreased significantly; Scr and BUN level, mRNA expression of α-SMA, mRNA and protein expressions of TGF-β1 and Col-Ⅳ were significantly reduced, while the mRNA expressions of P-cadherin, nephrin and WT1 were increased significantly (P<0.05); the protein deposition of α-SMA was reduced, protein depositions of P-cadherin, nephrin and WT1 were increased; the pathological damage and fibrosis of renal tissue were relieved; the thickness of glomerular basement membrane was decreased significantly (P<0.05). CONCLUSIONS Taohong siwu decoction modified granules can inhibit the EMT of podocyte in DKD model rats, and alleviate renal pathological damage and podocyte damage, thus protecting renal function, and delaying the process of renal fibrosis.

8.
China Pharmacy ; (12): 1327-1333, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1031730

RESUMO

OBJECTIVE To investigate the effects of Taohong siwu decoction modified granules on podocyte epithelial- mesenchymal-transition (EMT) and renal fibrosis in diabetic kidney disease (DKD) model rats. METHODS Eight rats were selected as normal group (ordinary feed); the remaining rats were given a high-glucose and high-fat diet combined with intraperitoneal injection of streptozotocin (35 mg/kg) to induce the DKD model. Model rats were randomly divided into model group, irbesartan group [positive control, 13.5 mg/(kg·d)] and modified Taohong siwu decoction group [6.48 g/(kg·d)], with 8 rats in each group. All groups were given relevant medicine intragastrically, once a day, for 16 consecutive weeks. Twenty-four- hour urinary total protein (24 h UTP) was detected at the end of the 4th, 8th, 12th and 16th week of administration. After the last medication, the body mass, water intake, food intake, urine output, the levels of fasting blood glucose, serum creatinine (Scr) and blood urea nitrogen (BUN) as well as mRNA and protein expressions of P-cadherin, nephrin, α -smooth muscle actin (α-SMA), Wilms’ tumor gene 1 (WT1), transforming growth factor-β1( TGF-β1) and type Ⅳ collagen (Col-Ⅳ) in renal tissue were determined. The pathological and morphological changes in renal tissue were observed and the thickness of the glomerular basement membrane was determined. RESULTS Compared with the model group, 24 h UTP of rats was significantly decreased in modified Taohong siwu decoction group since the 8th weekend (P<0.05); the body weight of rats increased significantly, but the amount of water intake and urine decreased significantly; Scr and BUN level, mRNA expression of α-SMA, mRNA and protein expressions of TGF-β1 and Col-Ⅳ were significantly reduced, while the mRNA expressions of P-cadherin, nephrin and WT1 were increased significantly (P<0.05); the protein deposition of α-SMA was reduced, protein depositions of P-cadherin, nephrin and WT1 were increased; the pathological damage and fibrosis of renal tissue were relieved; the thickness of glomerular basement membrane was decreased significantly (P<0.05). CONCLUSIONS Taohong siwu decoction modified granules can inhibit the EMT of podocyte in DKD model rats, and alleviate renal pathological damage and podocyte damage, thus protecting renal function, and delaying the process of renal fibrosis.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1024090

RESUMO

Objective To evaluate the clinical application value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)in analyzing the homology of Acinetobacter baumannii(AB).Methods After excluding repetitive strains from multiple specimens of the same patient or environment,a total of 46 AB strains isolated from patients'sputum and environmental specimens of neurological intensive care unit(ICU)in a tertiary first-class general hospital from May 2020 to February 2021 were collected.Strains were detected by VITEK-MS mass spectrometer.Cluster analysis was performed by SARAMIS Premium software,and verified by multilocus sequence typing(MLST).Results Cluster analysis and comparison of MALDI-TOF MS and MLST found that among the 46 AB strains,39 were the type MS-a of MALDI-TOF MS,of which 22 strains were the clus-ter MT-A of MLST,including ST208(n=3),ST540(n=3),ST195(n=8),ST369(n=5),ST136(n=1),ST436(n=1)and ST1893(n=1);16 strains were MT-B,including type ST381(n=4),type ST469(n=11),and type ST938(n=1);one strain was cluster MT-C(ST1821);one strain of type MS-b was ST381;two strains of type MS-c were ST369;one strain of type MS-d was ST195;two strains of type MS-e were ST540 and ST369,respectively;one strain of type MS-f was STN1.Conclusion As a homology analysis method,MALDI-TOF MS still has certain limitations such as low consistency with MLST results,low resolution and specificity,thus cannot replace MLST technology.

10.
Sci Rep ; 13(1): 12110, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495638

RESUMO

To study the basic mechanical behavior and the reloading reinforcement characteristics of fractured coal, conventional triaxial loading tests with different fissure angle were first carried out. On this basis, conventional triaxial loading and unloading tests were conducted to investigate the reloading reinforcement characteristics of fractured coal. The results reveal that when the fissure angle was small, the stress-strain curve exhibited the multi-peak phenomena. As the fissure angle increased, the stress drop phenomenon in the peak region was weakened. With the increase of the fissure angle, the peak stress of the specimens increased and then decreased, while the elastic modulus showed an overall increasing trend, demonstrating the controlling effect of the crack angle. Meanwhile, the cyclic loading exhibited a certain enhancement effect on the strength of the fractured coals when the specimens was unloaded near the crack closure stress. The findings can provide a better understanding of the failure mechanism and reloading reinforcement characteristics of fractured coal.

11.
Biomolecules ; 13(4)2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37189402

RESUMO

The gene encoding brain-derived neurotrophic factor (Bdnf) consists of nine non-coding exons driven by unique promoters, leading to the expression of nine Bdnf transcripts that play different roles in various brain regions and physiological stages. In this manuscript, we present a comprehensive overview of the molecular regulation and structural characteristics of the multiple Bdnf promoters, along with a summary of the current knowledge on the cellular and physiological functions of the distinct Bdnf transcripts produced by these promoters. Specifically, we summarized the role of Bdnf transcripts in psychiatric disorders, including schizophrenia and anxiety, as well as the cognitive functions associated with specific Bdnf promoters. Moreover, we examine the involvement of different Bdnf promoters in various aspects of metabolism. Finally, we propose future research directions that will enhance our understanding of the complex functions of Bdnf and its diverse promoters.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Esquizofrenia , Humanos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Regiões Promotoras Genéticas , Encéfalo/metabolismo , Éxons , Esquizofrenia/metabolismo
12.
Curr Med Sci ; 43(3): 478-488, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37243806

RESUMO

OBJECTIVE: We previously reported that mutations in inner mitochondrial membrane peptidase 2-like (Immp2l) increase infarct volume, enhance superoxide production, and suppress mitochondrial respiration after transient cerebral focal ischemia and reperfusion injury. The present study investigated the impact of heterozygous Immp2l mutation on mitochondria function after ischemia and reperfusion injury in mice. METHODS: Mice were subjected to middle cerebral artery occlusion for 1 h followed by 0, 1, 5, and 24 h of reperfusion. The effects of Immp2l+/- on mitochondrial membrane potential, mitochondrial respiratory complex III activity, caspase-3, and apoptosis-inducing factor (AIF) translocation were examined. RESULTS: Immp2l+/- increased ischemic brain damage and the number of TUNEL-positive cells compared with wild-type mice. Immp2l+/- led to mitochondrial damage, mitochondrial membrane potential depolarization, mitochondrial respiratory complex III activity suppression, caspase-3 activation, and AIF nuclear translocation. CONCLUSION: The adverse impact of Immp2l+/- on the brain after ischemia and reperfusion might be related to mitochondrial damage that involves depolarization of the mitochondrial membrane potential, inhibition of the mitochondrial respiratory complex III, and activation of mitochondria-mediated cell death pathways. These results suggest that patients with stroke carrying Immp2l+/- might have worse and more severe infarcts, followed by a worse prognosis than those without Immp2l mutations.


Assuntos
Ataque Isquêmico Transitório , Traumatismo por Reperfusão , Animais , Camundongos , Caspase 3/genética , Caspase 3/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Ataque Isquêmico Transitório/metabolismo , Membranas Mitocondriais/metabolismo , Mutação , Traumatismo por Reperfusão/metabolismo
13.
Biomolecules ; 13(5)2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37238691

RESUMO

The transcripts for Bdnf (brain-derived neurotrophic factor), driven by different promoters, are expressed in different brain regions to control different body functions. Specific promoter(s) that regulates energy balance remain unclear. We show that disruption of Bdnf promoters I and II but not IV and VI in mice (Bdnf-e1-/-, Bdnf-e2-/-) results in obesity. Whereas Bdnf-e1-/- exhibited impaired thermogenesis, Bdnf-e2-/- showed hyperphagia and reduced satiety before the onset of obesity. The Bdnf-e2 transcripts were primarily expressed in ventromedial hypothalamus (VMH), a nucleus known to regulate satiety. Re-expressing Bdnf-e2 transcript in VMH or chemogenetic activation of VMH neurons rescued the hyperphagia and obesity of Bdnf-e2-/- mice. Deletion of BDNF receptor TrkB in VMH neurons in wildtype mice resulted in hyperphagia and obesity, and infusion of TrkB agonistic antibody into VMH of Bdnf-e2-/- mice alleviated these phenotypes. Thus, Bdnf-e2-transcripts in VMH neurons play a key role in regulating energy intake and satiety through TrkB pathway.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Receptor trkB , Resposta de Saciedade , Animais , Camundongos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hiperfagia/genética , Hiperfagia/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Obesidade/genética , Obesidade/metabolismo , Receptor trkB/genética , Receptor trkB/metabolismo
14.
Antib Ther ; 6(2): 76-86, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37077472

RESUMO

Background: Rapid and efficient strategies are needed to discover neutralizing antibodies (nAbs) from B cells derived from virus-infected patients. Methods: Here, we report a high-throughput single-B-cell cloning method for high-throughput isolation of nAbs targeting diverse epitopes on the SARS-CoV-2-RBD (receptor binding domain) from convalescent COVID-19 patients. This method is simple, fast and highly efficient in generating SARS-CoV-2-neutralizing antibodies from COVID-19 patients' B cells. Results: Using this method, we have developed multiple nAbs against distinct SARS-CoV-2-RBD epitopes. CryoEM and crystallography revealed precisely how they bind RBD. In live virus assay, these nAbs are effective in blocking viral entry to the host cells. Conclusion: This simple and efficient method may be useful in developing human therapeutic antibodies for other diseases and next pandemic.

15.
China Pharmacy ; (12): 1584-1589, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-977846

RESUMO

OBJECTIVE To explore the intervention effect and related mechanism of Tongxinluo capsule on renal fibrosis in rats with diabetic nephropathy (DN). METHODS Eight rats were selected as control group (ordinary feed), the remaining rats were given high-glucose and high-fat diet combined with ip injection of streptozotocin (35 mg/kg) to induce DN model. Model rats were randomly divided into model group (purified water), irbesartan group (positive control, 14.12 mg/kg) and Tongxinluo capsule group (0.3 g/kg), including 12 rats in the model group and 11 rats for each of the other two groups. All groups were given relevant medicine or water intragastrically, once a day, for 16 consecutive weeks. After the last medication, fasting blood glucose and 24 h urinary total protein (24 h UTP) were detected. Pathological changes in renal cortex of rats in each group were observed. Serum levels of tissue-type plasminogen activator (PA) and plasminogen activator inhibitor 1 (PAI-1) were measured. mRNA expressions of transforming growth factor-β(1 TGF-β1), type Ⅳ collagen(COL-Ⅳ), Wnt4 and β-catenin in renal cortex of rats were detected. The protein depositions or expressions of TGF-β1, COL-Ⅳ, focal adhesion kinase (FAK), integrin-linked kinase (ILK), E-cadherin, PA, PAI-1, Wnt4 and β-catenin in renal cortex of rats were observed or determined. RESULTS Compared with model group, 24 h UTP of rats in Tongxinluo capsule group were all significantly reduced (P<0.05); pathological damage and fibrosis of renal cortex were relieved; the expression of PA in serum and renal cortex was significantly increased, while PAI-1 level was significantly reduced (P<0.05); the depositions of COL-Ⅳ and TGF-β1 in renal cortex were all reduced, and corresponding mRNA expression was decreased significantly (P<0.05); the depositions of ILK and FAK were decreased, while the deposition of E-cadherin was increased; protein and mRNA expressions of Wnt4 and β-catenin were significantly reduced (P<0.05). CONCLUSIONS Tongxinluo capsule can relieve pathological damage to renal tissue and renal fibrosis of DN model rats, and reduce extracellular matrix deposition. The mechanism may be related to regulation of fibrinolytic system activity, the decrease of ILK and FAK expression, and inhibition of Wnt/β-catenin signaling pathway.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981381

RESUMO

Rosae Radix et Rhizoma is a herbal medicine in a variety of famous Chinese patent medicines, while the quality standard for this medicine remains to be developed due to the insufficient research on the quality of Rosae Radix et Rhizoma from different sources. Therefore, this study comprehensively analyzed the components in Rosae Radix et Rhizoma of different sources from the aspects of extract, component category content, identification based on thin-lay chromatography, active component content determination, and fingerprint, so as to improve the quality control. The results showed that the content of chemical components varied in the samples of different sources, while there was little difference in the chemical composition among the samples. The content of components in the roots of Rosa laevigata was higher than that in the other two species, and the content of components in the roots was higher than that in the stems. The fingerprints of triterpenoids and non-triterpenoids were established, and the content of five main triterpenoids including multiflorin, rosamultin, myrianthic acid, rosolic acid, and tormentic acid in Rosae Radix et Rhizoma was determined. The results were consistent with those of major component categories. In conclusion, the quality of Rosae Radix et Rhizoma is associated with the plant species, producing area, and medicinal parts. The method established in this study lays a foundation for improving the quality standard of Rosae Radix et Rhizoma and provides data support for the rational use of the stem.


Assuntos
Medicamentos de Ervas Chinesas/química , Rizoma/química , Raízes de Plantas/química , Plantas Medicinais , Controle de Qualidade
17.
Chinese Journal of Epidemiology ; (12): 624-628, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-985537

RESUMO

Objective: We analyze the characteristics of Clostridioides difficile (C. difficile) infection among diarrhea patients in Kunming from 2018 to 2020 and provide evidence for follow-up surveillance and prevention. Methods: A total of 388 fecal samples of diarrhea patients from four sentinel hospitals in Yunnan Province from 2018 to 2020 were collected. Real-time quantitative PCR was used to detect the fecal toxin genes of C. difficile. The positive fecal samples isolated the bacteria, and isolates were identified by mass spectrometry. The genomic DNA of the strains was extracted for multi-locus sequence typing (MLST). The fecal toxin, strain isolation, and clinical patient characteristics, including co-infection with other pathogens, were analyzed. Results: Among the 388 fecal samples, 47 samples with positive reference genes of C. difficile were positive, with a total positive rate of 12.11%. There were 4 (8.51%) non-toxigenic and 43 (91.49%) toxigenic ones. A total of 18 strains C. difficile were isolated from 47 positive specimens, and the isolation rate of positive specimens was 38.30%. Among them, 14 strains were positive for tcdA, tcdB, tcdC, tcdR, and tcdE. All 18 strains of C. difficile were negative for binary toxins. The MLST results showed 10 sequence types (ST), including 5 strains of ST37, accounting for 27.78%; 2 strains of ST129, ST3, ST54, and ST2, respectively; and 1 strain of ST35, ST532, ST48, ST27, and ST39, respectively. Fecal toxin gene positive (tcdB+) results were statistically associated with the patient's age group and with or without fever before the visit; positive isolates were only statistically associated with the patient's age group. In addition, some C. difficile patients have co-infection with other diarrhea-related viruses. Conclusions: The infection of C. difficile in diarrhea patients in Kunming is mostly toxigenic strains, and the high diversity of strains was identified using the MLST method. Therefore, the surveillance and prevention of C. difficile should be strengthened.


Assuntos
Humanos , Toxinas Bacterianas/genética , Enterotoxinas/genética , Clostridioides difficile/genética , Tipagem de Sequências Multilocus , Coinfecção , Proteínas de Bactérias/genética , China/epidemiologia , Infecções por Clostridium/epidemiologia , Diarreia/microbiologia
18.
Chinese Journal of Epidemiology ; (12): 636-642, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-985539

RESUMO

Objective: To establish and optimize PCR methods for the gene encoding of Clostridium perfringens β2 toxin (cpb2) and atypical-cpb2 (aty-cpb2), analyze the epidemiological characteristics and genetic polymorphism of the cpb2 of Clostridium perfringens in 9 Chinese areas from 2016 to 2021. Methods: The cpb2 of 188 Clostridium perfringens strains were examined by PCR; the cpb2 sequences were acquired by whole-genome sequencing to analyze the genetic polymorphism. Using Mega 11 and the Makeblastdb tool, a phylogenetic tree, and cpb2-library based on 110 strains carrying the cpb2 were produced. Using the Blastn technique, a comparison was made to discover sequence similarity between consensus-cpb2 (con-cpb2) and aty-cpb2. Results: The specificity of PCR assay for the cpb2 and aty-cpb2 was verified. The PCR results for cpb2 amplification were highly consistent with the whole-genome sequencing approach (Kappa=0.946, P<0.001). A total of 107 strains from nine regions in China carried cpb2, 94 types A strains carried aty-cpb2, 6 types A strains carried con-cpb2, and 7 types F strains carried aty-cpb2. The nucleotide sequence similarity between the two coding genes was 68.97%-70.97%, and the similarity between the same coding genes was 98.00%-100.00%. Conclusions: In this study, a specific PCR method for cpb2 toxin was developed, and the previous PCR method for detecting aty-cpb2 was improved. aty-cpb2 is the primary gene encoding of β2 toxin. There is a significant nucleotide sequence variance between the various cpb2 genotypes.


Assuntos
Humanos , Clostridium perfringens/genética , Infecções por Clostridium , Toxinas Bacterianas/genética , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Genético
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-985993

RESUMO

Objective: To analyze the efficacy and safety of letermovir in primary prophylaxis of cytomegalovirus (CMV) reactivation in patients receiving haploidentical hematopoietic stem cell transplantation. Methods: This retrospective, cohort study was conducted using data of patients who underwent haploidentical transplantation at Peking University Institute of Hematology and received letermovir for primary prophylaxis between May 1, 2022 and August 30, 2022. The inclusion criteria of the letermovir group were as follows: letermovir initiation within 30 days after transplantation and continuation for≥90 days after transplantation. Patients who underwent haploidentical transplantation within the same time period but did not receive letermovir prophylaxis were selected in a 1∶4 ratio as controls. The main outcomes were the incidence of CMV infection and CMV disease after transplantation as well as the possible effects of letermovir on acute graft versus host disease (aGVHD), non-relapse mortality (NRM), and bone marrow suppression. Categorical variables were analyzed by chi-square test, and continuous variables were analyzed by Mann-Whitney U test. The Kaplan-Meier method was used for evaluating incidence differences. Results: Seventeen patients were included in the letermovir prophylaxis group. The median patient age in the letermovir group was significantly greater than that in the control group (43 yr vs. 15 yr; Z=-4.28, P<0.001). The two groups showed no significant difference in sex distribution and primary diseases, etc. (all P>0.05). The proportion of CMV-seronegative donors was significantly higher in the letermovir prophylaxis group in comparison with the control group (8/17 vs. 0/68, χ2=35.32, P<0.001). Three out of the 17 patients in the letermovir group experienced CMV reactivation, which was significantly lower than the incidence of CMV reactivation in the control group (3/17 vs. 40/68, χ2=9.23, P=0.002), and no CMV disease development observed in the letermovir group. Letermovir showed no significant effects on platelet engraftment (P=0.105), aGVHD (P=0.348), and 100-day NRM (P=0.474). Conclusions: Preliminary data suggest that letermovir may effectively reduce the incidence of CMV infection after haploidentical transplantation without influencing aGVHD, NRM, and bone marrow suppression. Prospective randomized controlled studies are required to further verify these findings.


Assuntos
Humanos , Citomegalovirus , Estudos Retrospectivos , Estudos de Coortes , Estudos Prospectivos , Infecções por Citomegalovirus/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Recidiva , Antivirais/uso terapêutico
20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-990568

RESUMO

Objective:To explore the association between the G71R polymorphism of the UGT1A1 gene and neonatal hyperbilirubinemia. Methods:DNA was extracted from blood samples of 61 neonates with severe neonatal hyperbilirubinemia(severe neonatal hyperbilirubinemia group), 60 neonates with hyperbilirubinemia(hyperbilirubinemia group) and 62 healthy neonates(control group), the G71R mutation of UGT1A1 gene was analyzed by direct sequencing. Results:In severe neonatal hyperbilirubinemia group, there were 17 cases of homozygous mutation(A/A), 23 cases of heterozygous mutation(A/G) , and 21 cases of wild type(G/G) , with 28.87% homozygous mutation rate and 37.70% heterozygous mutation rate.In neonatal hyperbilirubinemia group, there were ten cases of homozygous mutation(A/A), 28 cases of heterozygous mutation(A/G) and 22 cases of wild type(G/G), with 16.67% homozygous mutation rate and 46.67% heterozygous mutation rate.In the control group, there were nine cases of homozygous mutation (A/A), 28 cases of heterozygous mutation(A/G) and 25 cases of wild type(G/G), among which the homozygous mutation rate was 14.52% and the heterozygous mutation rate was 45.16%.The genotype frequency( χ2=4.14, P=0.38)and allele frequency( χ2=2.47, P=0.29)of G71R in severe neonatal hyperbilirubinemia group, neonatal hyperbilirubinemia group and control group were not statistically significant. Conclusion:The G71R polymorphism of the UGT1A1 gene may not be significantly correlated with the prevalence of neonatal hyperbilirubinemia.

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