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1.
Microb Pathog ; 175: 105965, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592640

RESUMO

The release of extracellular vesicles (EV) by pathogenic microbes is considered an alternative cell-to-cell transport of macromolecules transport mechanism. In Gram-negative bacteria, EVs may be formed by outer membrane budding, so-called outer membrane vesicles (OMVs). Previous studies have revealed E. coli constitutively release nano-sized OMVs, which can be potent activators of cellular functions without live bacteria. But the immunomodulatory activity of E. coli OMVs is still relatively poorly understood. Here we investigated the morphological characterization and composition of E.Coli OMVs, kinetics of internalization by Raw 264.7 macrophage cells, and their immunomodulatory activity on cells. By transmission electron microscopy and dynamic light scattering, E.Coli OMVs were identified as typical cup-shaped, bilayered membranous structures, mainly distributed between 72.5 and 212.5 nm. We also demonstrated by confocal fluorescence microscopy that exposure of Raw 264.7 cells to E.Coli OMVs resulted in internalization of these nanoparticles and decreased mitochondrial membrane potential. In addition, E. Coli OMVs treatment induced the production of ROS, iNOS, IL-1ß, IL-6, IL-10 and up-regulation of CD86 and CD206. Taken together, our results indicated that E.Coli OMVs are immunobiologically active, can directly interact with macrophage and participate in immune responses.


Assuntos
Escherichia coli , Vesículas Extracelulares , Macrófagos , Endocitose , Proteínas da Membrana Bacteriana Externa
2.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-293035

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly become a global public health threat due to the lack of effective drugs or vaccines against SARS-CoV-2. The efficacy of several repurposed drugs has been evaluated in clinical trials. Among these drugs, a relatively new antiandrogen agent, enzalutamide, was proposed because it reduces the expression of transmembrane serine protease 2 (TMPRSS2), a key component mediating SARS-CoV-2-driven entry into host cells, in prostate cancer cells. However, definitive evidence for the therapeutic efficacy of enzalutamide in COVID-19 is lacking. Here, we evaluated the antiviral efficacy of enzalutamide in prostate cancer cells, lung cancer cells, human lung organoids and SARS-CoV-2-infected Ad-ACE2-transduced Tmprss2 knockout (Tmprss2-KO) and wild-type (WT) mice. TMPRSS2 knockout significantly inhibited SARS-CoV-2 infection in vivo. Enzalutamide effectively inhibited SARS-CoV-2 infection in human prostate cancer cells (LNCaP) but not in human lung cancer cells or patient-derived lung organoids. Although Tmprss2 knockout effectively blocked SARS-CoV-2 infection in ACE2-transduced mice, enzalutamide showed no antiviral activity due to the AR independence of TMPRSS2 expression in mouse and human lung epithelial cells. Moreover, we observed distinct AR binding patterns between prostate cells and lung cells and a lack of direct binding of AR to TMPRSS2 in human lung cells. Thus, our findings do not support the postulated protective role of enzalutamide in treating COVID-19.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20126201

RESUMO

BackgroundMales and females differ in their immunological responses to foreign pathogens. However, most of the current COVID-19 clinical practices and trials do not take sex as consideration. MethodsWe performed an unbiased sex-based comparative analysis for the clinical outcomes, peripheral immune cells, and SARS-CoV-2 specific antibody levels of 1,558 males and 1,499 females COVID-19 patients from a single center. The lymphocyte subgroups were measured by Flow cytometry. Total antibody, Spike protein (S)-, receptor binding domain (RBD)-, and nucleoprotein (N)-specific IgM and IgG levels were measured by chemiluminescence. ResultsWe found that the mortality and ICU admission rates were approximately 2-fold higher in males than that in females (P<0.005). Survival analysis revealed that sex is an independent prognostic factor for COVID-19 (Hazard ratio=2.2, P=0.003). The concentration of inflammatory factors in peripheral blood was significantly higher in males. Besides, the renal and hepatic abnormality induced by COVID-19 was more common in males during the hospitalization. The analysis of lymphocyte subsets revealed that the percentage of CD19+ B cell and CD4+ T cell was significantly higher in females (P<0.001) during hospitalization, indicating the stronger humoral immunity in females than males. Notably, the protective IgG sharply increased and reached a peak in the fourth week after symptom onset in females, while gradually increased and reached a peak in the seventh week in males. ConclusionsThe unfavorable prognosis of male COVID-19 patients may result from the weak humoral immunity and indolent antibody responses during SARS-CoV-2 infection and recovery. Early medical intervention and close monitoring are important, especially for male COVID-19 patients. Hormonal or convalescent plasma therapy may help improve the immunity of males to fight against SARS-CoV-2 infection.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20172452

RESUMO

The capacity to accurately diagnosis COVID-19 is essential for effective public health measures to manage the ongoing global pandemic, yet no presently available diagnostic technologies or clinical protocols can achieve full positive predictive value (PPV) and negative predictive value (NPV) performance. Two factors prevent accurate diagnosis: the failure of sampling methods (e.g., 40% false negatives from PCR testing of nasopharyngeal swabs) and sampling-time-dependent failures reflecting individual humoral responses of patients (e.g., serological testing outside of the sero-positive stage). Here, we report development of a diagnostic protocol that achieves full PPV and NPV based on a cohort of 500 confirmed COVID-19 cases, and present several discoveries about the sero-conversion dynamics throughout the disease course of COVID-19. The fundamental enabling technology for our study and diagnostic protocol--termed SANE, for Symptom (dpo)-Antibody-Nucleic acid-Epidemiological history--is our development of a peptide-protein hybrid microarray (PPHM) for COVID-19. The peptides comprising PPHMO_SCPLOWCOVIDC_SCPLOWO_SCPCAP-19C_SCPCAP were selected based on clinical sample data, and give our technology the unique capacity to monitor a patients humoral response throughout the disease course. Among other assay-development related and clinically relevant findings, our use of PPHMO_SCPLOWCOVIDC_SCPLOWO_SCPCAP-19C_SCPCAP revealed that 5% of COVID-19 patients are from an "early sero-reversion" subpopulation, thus explaining many of the mis-diagnoses we found in our comparative testing using PCR, CLIA, and PPHMO_SCPLOWCOVIDC_SCPLOWO_SCPCAP-19C_SCPCAP. Accordingly, the full SANE protocol incorporates orthogonal technologies to account for these patient variations, and successfully overcomes both the sampling method and sampling time limitations that have previously prevented doctors from achieving unambiguous, accurate diagnosis of COVID-19.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20129098

RESUMO

The high mortality rate of COVID-19 patients is mainly caused by the progression from mild to critical illness. To identify the key laboratory indicators and stratify high-risk COVID-19 patients with progression to severe/critical illness, we compared 474 moderate patients and 74 severe/critical patients. The laboratory indicators, including lactate dehydrogenase (LDH), monocytes percentage, etc. were significantly higher in the severe/critical patients (P <0.001) and showed a noticeable change at about a week before the diagnosis. Based on these indicators, we constructed a risk-stratification model, which can accurately grade the severity of patients with COVID-19 (accuracy = 0.96, 95% CI: 0.94 - 0.989, sensitivity = 0.98, specificity = 0.84). Also, compared with non-COVID-19 viral pneumonia, we found that COVID-19 had weaker dysfunction to the heart, liver, and kidney. The prognostic model based on laboratory indicators could help to diagnose, monitor, and predict severity at an early stage to those patients with COVID-19.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20105155

RESUMO

Deciphering the dynamic changes of antibodies against SARS-CoV-2 is essential for understanding the immune response in COVID-19 patients. By comprehensively analyzing the laboratory findings of 1,850 patients, we describe the dynamic changes of the total antibody, spike protein (S)-, receptor-binding domain (RBD)-, and nucleoprotein (N)- specific IgM and IgG levels during SARS-CoV-2 infection and recovery. Our results indicate that the S-, RBD-, and N- specific IgG generation of severe/critical COVID-19 patients is one week later than mild/moderate cases, while the levels of these antibodies are 1.5-fold higher in severe/critical patients during hospitalization (P<0.01). The decrease of these IgG levels indicates the poor outcome of severe/critical patients. The RBD- and S-specific IgG levels are 2-fold higher in virus-free patients (P<0.05). Notably, we found that the patients who got re-infected had a low level of protective antibody on discharge. Therefore, our evidence proves that the dynamic changes of antibodies could provide an important reference for diagnosis, monitoring, and treatment, and shed new light on the precise management of COVID-19.

7.
Molecules ; 24(22)2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31698810

RESUMO

Five new meroterpenoids, clavipols A-B (1-2) with a 12-membered ether ring and clavilactones G-I (3-5) having a 10-membered carbocycle connected to a hydroquinone and an α,ß-epoxy/unsaturated lactone, were obtained from the fruiting bodies of the basidiomycete Clitocybe clavipes. Their structures were determined by comprehensive analysis of their spectroscopic data, and the absolute configuration of 1 was established by quantum chemical calculations of electronic circular dichroism (ECD). All the isolated compounds (1-5) were tested for their cytotoxic activity against three human tumor cell lines (Hela, SGC-7901, and SHG-44) in vitro after treatment for 48 h. Compound 4 exhibited moderate cytotoxic activity against Hela and SGC-7901 tumor cell lines, with IC50 values of 23.5 and 14.5 µM, respectively.


Assuntos
Antineoplásicos/farmacologia , Basidiomycota/química , Carpóforos/química , Terpenos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Modelos Moleculares , Estrutura Molecular , Terpenos/química
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-608141

RESUMO

Objective Our purpose was to investigate the pathogenic gene mutation of a Han Chinese family with vitreous amyloidosis.Methods The 9 individuals(proband,1 affected member and 7 unaffected members) of the family were selected and their DNA was extracted from peripheral blood.The 4 exons of transthyretin(TTR) gene were amplified by polymerase chain reaction(PCR) technique.The amplified products of TTR gene were sequencing by Sanger technique.We also selected 100 unrelated healthy individual as the control group.Results By DNA sequencing,a heterozygous mutation was found in 4 of the 9 subjects from the family.The transition of adenine to cytosine(AAG > ACG) was detectable in exon 2 of TTR,which changed the amino acid composition at codon 35 (Lys35Thr).This mutation did not presented in control group.Conclusion The heterozygosis mutation of TTR gene Lys35Thr should be a pathogenic mutation for the family with vitreous amyloidosis.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-594142

RESUMO

Objective To report a familial dentinogenesis imperfecta type Ⅱ (DGI type Ⅱ) with a novel splicing mutation in DSPP (dentin sialophosphoprotein) gene.Methods Based on the result of linkage analysis performed previously to map the candidate gene DSPP in the family, the promoter,the first four exons and exon-intron boundaries of DSPP were directly sequenced for the members of the DGI type Ⅱ family. Denaturing high performance liquid chromatography (DHPLC) analysis was performed to confirm the results of sequencing.Results A novel splicing mutation of 23 bp deletion in intron 2 of DSPP gene was identified by DNA sequence analysis. The mutation changed acceptor site sequence from CAG to AAG, and might result in functional abolition of possible branch point site in intron 2. DHPLC result was consistent with that of sequencing. The mutation may be identified in all affected individuals, but not found in normal members of the family and 50 controls.Conclusion These results suggest the deleted mutation of DSPP gene causes DGI type Ⅱ in the family. The mutation has not been reported before.

10.
National Journal of Andrology ; (12): 925-927, 2004.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-267778

RESUMO

<p><b>OBJECTIVE</b>To acquire purified recombinant human epididymal sperm protein P34H for basic and clinical studies.</p><p><b>METHODS</b>On the basis of cloning of P34H coding region, P34H fragment was subcloned into the pQE-30 expression vector. The recombinant expression vector designated pQE-30/P34H was transformed into E. coli to induce the expression of the recombinant protein P34H on the reduction of IPTG. After sonication, the recombinant protein P34H was purified from the supernatant with Ni-NTA resin under native conditions. It was identified by SDS-PAGE analysis and DNA sequencing.</p><p><b>RESULTS</b>Recombinant expression vector pQE-30/P34H was correctly constructed, identified with PCR and double-enzyme digestion. And the results of SDS-PAGE analysis and DNA sequencing showed that the protein was what we had hoped to acquire.</p><p><b>CONCLUSION</b>Purified recombinant P34H can be acquired successfully with the above mentioned prokaryotic expression method.</p>


Assuntos
Humanos , Masculino , Clonagem Molecular , Expressão Gênica , Vetores Genéticos , Proteínas Recombinantes , Desidrogenase do Álcool de Açúcar , Genética
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-584801

RESUMO

Objective:To investigate a large Chinese family in which 9 patients over 4 generations were diagnosed with a form of autosomal dominant spondyloepimphyseal dysplasia(SEMD).Mothods:X-Ray radiograph of proand at 18-month showed absence of secondary ossification centra of femoral heads.His father at 24-year presented severe spondyloepiphyseal changes that principally involved the vertebral bodies,the femoral necks and femoral heads and characterized by generalized platyspondyly with thoracolumbar scoliosis,irregular femoral necks,absent ossification of femoral heads,flat acetabular roofs and coxa vara.The other patients had similar clinical and radiological features.Haplotyping was performed with leukocyte DNA for 5 micosatellite repeat markers from chromosome 12 and the result showed COL2A1 gene as a candidate gene.A total of 54 exons and promoter of COL2A1 gene were amplified and sequenced from all patients and available normal relatives.In addition,exon 23 of COL2A1 gene was amplified and sequenced from 10 controls simultaneously.Results:All patients were identified a 1510(G→A) transition in exon 23 of COL2A1 gene that caused a change from a COL2A1 coding region in available glycine to serine at amino acid position 504.No mutation was found in the normal relatives and 10 controls. Conclusion:The mutation of COL2A1 gene is responsible for this form of SEDC of the family.This is the first familial report of SEDC relating to 1510G→A mutation of COL2A1 gene.The detailed clinical radiogram data will be useful for extending the phenotypic spectrum of type Ⅱcollagenopathies.

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-588683

RESUMO

Objective:To explore the relationship between DNA ploidy heterogeneity and clinical biological behavior on patients with malignant tumor.Methods:The DNA ploidy heterogeneity of tumor tissue was measured in 163 patients with malignant tumors by flow cytometry.The relations were analyzed between DNA ploidy heterogeneity and clinical stage,pathological grade,metastasis rate of patients with malignant tumors.Results:The rates of DNA ploidy heterogeneity were significantly different in different tumors.The rates of heterogeneity raised with increase of clinical stage and pathological grade(P

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-591943

RESUMO

Objective: To observe the influence of all-trans retinoic acid(ATRA) on the expressions of E-cadherin,heparanase and VEGF in epithelial ovarian carcinoma cell line COC2,and to investigate the anti-metastatic potential and possible action mechanism of ATRA.Methods: We used flow cytometry to examine the expressions of E-cadherin,heparanase and VEGF proteins in the epithelial ovarian carcinoma cell line COC2 treated with different concentrations of ATRA.Results: ATRA significantly increased the expression of E-cadherin and decrease that of VEGF and hepareanse in a dose-dependent manner.Conclusion: ATRA can inhibit cell proliferation,improve cell-cell adhesion and downregulate the expressions of VEGF and heparanse proteins,suggestive of an anti-angiogenic and anti-metastatic potential.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-592660

RESUMO

Objective: To explore the emergency treatment of acute respiratory tract injury caused by inhalation of phosphorus trichloride.Methods: The clinical data of 16 patients with acute respiratory tract injury caused by inhalation of phosphorus trichloride were analyzed.Intratracheal inhalation of salbutamol sulfate solution and pulmicort repules atomized liquid by aerosol rebreathing method was performed immediately after the diagnosis was made.Anti-inflammatory,fluid replacement,and other symptomatic treatment were given at the same time.Treatment lasted for 3-5 days.Results: The symptoms and signs improved significantly after 3-5 times of inhalation.Among the 16 patients,15 were cured and one improved;the cure rate was 93.75%.The shortest observation period was 2 days and the longest 7 days with an average period of 2.38 days.All cases were followed up for 3 months.No complications were found except one with pleural thickening.Conclusion: Early treatment of acute respiratory tract injury with intratracheal corticosteroid and?2 receptor activator is satisfactory for patients with inhalation of phosphorus trichloride.The method is fast-acting,efficient,with less side-effects,convenient,and easily accepted by patients.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-593233

RESUMO

Objective: To report a case of azoospermia with a karyotype of 45,X,der(Y)t(Y;13)(q11.2;q12),-13,accompanied with slight bilateral gynecomastia and multiple nodules.Methods: The karyotype was identified by karyotyping and FISH,and the breakpoints of the Y chromosome and the copy number of the BRCA2 gene in 13q12 determined by PCR-STS and DNA polymorphic analysis.The testis and nodule tissues of the patient were obtained for biopsy.Results: FISH confirmed SRY and centromere of the Y chromosome on the questionable 13 chromosome and the karyotype to be 45,X,der(Y)t(Y;13)(q11.1;q12),-13.ish der(Y)(SRY+,DYZ3+,wcp13+).PCR-STS showed the deletion of regions AZFa,b and C,with a breakpoint located inYq11.1 below sY82.No deletion of the BRCA2 gene was observed.The patient was diagnosed with Sertoli cell-only syndrome by testicular biopsy and with angiolipomata by pathological examination of the nodule tissue.Conclusion: The patient's phenotype of complete masculinization could be attributed to presence of the SRY gene,and his azoospermia with small testis to the absence of a fragment from Yq11.1 to Yqter.However,the molecular mechanism of angiolipoma remains unknown.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-594230

RESUMO

A) in COL1A1 gene resulting in OI in a Chinese family. The detailed molecular and clinical features will be useful for extending the evidence for genetic and phenotypic heterogeneity in OI and exploring the phenotype-genotype correlations in OI.

17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-596467

RESUMO

Spondyloepiphyseal dysplasia(SED) includes a group of disorders that cause deformation of vertebrae and epiphyses following gene mutations.Its main clinical manifestations are short stature(with a disproportionately short-trunk),chest malformation and early-onset joint degeneration.These disorders are broadly categorized into two subtypes: congenita(SEDC) and tarda(SEDT).In the 2006 revision of the International Nosology and Classification of Genetic Skeletal Disorders,372 different conditions were listed,of which 215 were associated with one or more of 140 different genes.SEDC has consistently been shown to correlate with defects in the gene COL2A1 on the long arm of chromosome 12,whose product is needed to form normal type-Ⅱ collagen.The gene responsible for SEDT is SEDL,mapped to the short arm of the X chromosome(Xp22).This paper briefly reviews the progress in the studies of molecular genetics of SEDC,SEDT and other rare forms of SED,which might provide some practical help for genetic and prenatal diagnoses of SED.

18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-589396

RESUMO

Objective To report the prenatal molecular diagnosis for two gravida in a family with spondylepiphyseal dysplasia congenita(SEDC)caused by G504S mutation of COL2A1 gene.Methods DNA of the two fetuses was extracted from amniotic fluid at the 19+3 and 18+6 weeks of gestation respectively.Direct sequencing of two samples were performed after amplifying exon 23 of COL2A1 containing the potential mutation.The femur length and biparietal diameter of the first fetus were measured by sonographic scans every two weeks from 17+3 weeks to 27+3 weeks of gestation,and for the second fetus these parameters were measured from 16+1 to 19+1 weeks of gestation.Results Sequncing analysis revealed the first fetus and his mother presented the same mutation which is specifically associated with SEDC,but the second fetus did not show the mutation of COL2A1 gene.Biparietal diameters of the both fetuses were appropriate for gestational age.Femur length of the second fetus was normal for gestational age but that of the first fetus was shortened evidently after the 23 week of gestation.The parents of the first fetus determined to terminate the pregnancy.A medical termination was carried out at 27+5 weeks of gestation and a male fetus with a relatively large head and short limbs was delivered.The radiological findings of the fetus were consistent with SEDC including generalized platy spondesand shortened long bones.Conclusions Prenatal molecular diagnosis is important for the fetus with risk of SEDC and useful for genetic counseling.Genotype of fetus with risk of SEDC can be identified before sonographic scan.Molecular genetic analysis in conjunction with sonographic monitoring was helpful in prenatal diagnosis of SEDC.

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