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1.
Bioelectromagnetics ; 39(7): 539-546, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30289990

RESUMO

Accumulating evidence does not yet confirm the effect of power line frequency magnetic field (MF) on human health and fertility. We recently reported that, at continuous 60 Hz MF exposure in mice, the dose given as magnetic flux density (tesla; T) and duration of exposure was related to induce testicular germ cell apoptosis. We aimed to characterize the effect of a 20-week continuous exposure to 60 Hz MF on the motility, morphology, and number of sperm as well as the apoptosis of testicular germ cell in rats. Sprague-Dawley rats were exposed for 20 weeks to 60 Hz MF of 2, 20, or 200 µT for 24 h/day with rats exposed to sham conditions, serving as the control. The exposure to 60 Hz MF of 2 and 20 µT had no effects on testicular in this study. The exposure to 60 Hz MF of 200 µT for 20 weeks induced increases of the apoptotic cells (P < 0.001) in germ cells and decreases of sperm numbers (P < 0.05). However, the MF did not significantly affect the body or testis mass, seminiferous tubule diameter, or the motility or morphology of sperm. This study concluded that exposure to 60 Hz MF of 200 µT can increase testicular germ cell apoptosis, especially spermatogonia, and reduce sperm count. Also compared to previous mice studies, rats are less sensitive than mice to exposure to 60 Hz MF. Bioelectromagnetics. 39:539-546, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Campos Magnéticos/efeitos adversos , Testículo/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Fatores de Tempo
2.
J Korean Med Sci ; 31(2): 183-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26839470

RESUMO

Leptospirosis, a zoonotic disease that is caused by many serovars which are more than 200 in the world, is an emerging worldwide disease. Accurate and rapid diagnostic tests for leptospirosis are a critical step to diagnose the disease. There are some commercial kits available for diagnosis of leptospirosis, but the obscurity of a species- or genus-specific antigen of pathogenic Leptospira interrogans causes the reduced sensitivity and specificity. In this study, the polysaccharide derived from lipopolysaccharide (LPS) of nonpathogenic Leptospira biflexa serovar patoc was prepared, and the antigenicity was confirmed by immunoblot and enzyme linked immunosorbent assay (ELISA). The performance of the rapid diagnostic test (RDT) kit using the polysaccharide as a diagnostic antigen was evaluated in Korea, Bulgaria and Argentina. The sensitivity was 93.9%, 100%, and 81.0% and the specificity was 97.9%, 100%, and 95.4% in Korea (which is a rare region occurring with 2 serovars mostly), Bulgaria (epidemic region with 3 serovars chiefly) and Argentina (endemic region with 19 serovars mainly) respectively. These results indicate that this RDT is applicable for global diagnosis of leptospirosis. This rapid and effective diagnosis will be helpful for diagnosis and manage of leptospirosis to use and the polysaccharide of Leptospira may be called as genus specific antigen for diagnosis.


Assuntos
Antígenos de Bactérias/imunologia , Leptospirose/diagnóstico , Polissacarídeos/imunologia , Kit de Reagentes para Diagnóstico/normas , Argentina , Bulgária , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Leptospira/isolamento & purificação , Leptospira/metabolismo , Leptospira interrogans/isolamento & purificação , Leptospira interrogans/metabolismo , Leptospirose/microbiologia , Masculino , República da Coreia , Sensibilidade e Especificidade
3.
J Korean Med Sci ; 31(8): 1190-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27478327

RESUMO

Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.


Assuntos
Tifo por Ácaros/diagnóstico , Anticorpos Antibacterianos/sangue , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Orientia tsutsugamushi/imunologia , Kit de Reagentes para Diagnóstico , Estudos Retrospectivos , Tifo por Ácaros/microbiologia , Sensibilidade e Especificidade
5.
Bioelectromagnetics ; 35(2): 100-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24123080

RESUMO

To evaluate duration- and dose-dependent effects of continuous exposure to a 60 Hz magnetic field (MF) on the testes in mice, BALB/c male mice were exposed to a 60 Hz MF at 100 µT for 24 h a day for 2, 4, 6, or 8 weeks, and at 2, 20, or 200 µT for 24 h a day for 8 weeks. Any exposures to MF did not significantly affect body or testicular masses. However, the apoptotic cells among testicular germ cells were increased duration-dependent at exposures of 100 µT for 6 and 8 weeks and dose-dependent at exposures of 20 and 200 µT for 8 weeks. The number of sperm in epididymis and the diameter of seminiferous tubule decreased in mice exposed to 100 and 200 µT for 8 weeks, respectively. To induce the apoptosis of testicular germ cell in mice, the minimum dose is 20 µT at continuous exposure to a 60 Hz MF for 8 weeks and the minimum duration is 6 weeks at continuous exposure of 100 µT. Taken together, these results suggest that continuous exposure to a 60 Hz MF might affect, duration- and dose-dependent biological processes including apoptotic cell death and spermatogenesis in the male reproductive system of mice.


Assuntos
Apoptose , Campos Magnéticos , Espermatozoides/citologia , Testículo/citologia , Animais , Relação Dose-Resposta à Radiação , Epididimo/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Espermatozoides , Fatores de Tempo
6.
J Korean Med Sci ; 28(5): 672-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23678257

RESUMO

Diagnosis of scrub typhus is difficult because its symptoms are very similar to other acute febrile illnesses, such as leptospirosis, murine typhus, and other viral hemorrhagic fevers. To differentiate scrub typhus from other acute febrile diseases, a rapid and reliable serological diagnosis is important. We have developed a chimeric recombinant antigen cr56 and two other recombinant antigens, r21 and kr56, from various serotypes of Orientia tsutsugamushi. They were tested for the detection of antibodies against O. tsutsugamushi in the patient's serum samples using enzyme-linked immunosorbent assay (ELISA) and dot-blot analyses. As of conventional immunofluorescence assay (IFA), when the mixture of these three recombinant antigens was used, both sensitivity and specificity of the recombinant antigens were increased up to 98% in IgM and IgG at ELISA and dot blotting. Additionally, both sensitivity and specificity by detection of IgM and IgG antibodies at rapid diagnostic test (RDT), using the mixture of three antigens and gold conjugated antibodies, were 99%. Our results suggest the use of mixture of these recombinant antigen proteins in ELISA or RDT is suitable as a diagnostic test for scrub typhus.


Assuntos
Orientia tsutsugamushi/metabolismo , Tifo por Ácaros/diagnóstico , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Ouro/química , Humanos , Imunoensaio , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Orientia tsutsugamushi/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Sensibilidade e Especificidade , Sorotipagem
7.
J Clin Med ; 11(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35683351

RESUMO

Humanized Virus Suppressing Factor-variant 13 (hzVSF-v13), a monoclonal IgG4 antibody against vimentin, was investigated in moderate to severe COVID-19 pneumonia through a Phase II study. Patients were randomized to two different IV doses of the test drug or saline with standard of care. Overall, 64 patients were recruited, and 62 entered the efficacy assessment in the full analysis set. Primary endpoint: The clinical failure rate at day 28 was 15.8% for placebo, 9.1% for low-dose hzVSF-v13 and 9.5% for high-dose hzVSF-v13 (not significant). A trend toward better efficacy was shown in several secondary endpoints, with statistical significance between low-dose hzVSF-v13 and placebo in terms of the rate of improved patients on the ordinal scale for clinical improvement (OSCI): 90.0% vs. 52.63% (p = 0.0116). In the severe stratum, the results of low-dose hzVSF-v13 vs. placebo were 90.0% and 22.2% for OSCI (p = 0.0092), 9 days and 14 days for time to discontinuation of oxygen therapy (p = 0.0308), 10 days and 15 days for both time to clinical improvement (TTCI) and time to recovery (TTR) and p = 0.0446 for both TTCI and TTR. Change from baseline of NEWS2 score at day 28 was -3.4 vs. + 0.4 (p = 0.0441). The results propose hzVSF-v13 as a candidate in the treatment of severe COVID-19.

9.
Cells ; 10(9)2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34571970

RESUMO

Current treatment options for patients infected with hepatitis B virus (HBV) are suboptimal, because the approved drugs rarely induce cure due to the persistence of the viral DNA genome in the nucleus of infected hepatocytes, and are associated with either severe side effects (pegylated interferon-alpha) or require life-long administration (nucleos(t)ide analogs). We report here the evaluation of the safety and therapeutic efficacy of a novel, humanized antibody (hzVSF) in the woodchuck model of HBV infection. hzVSF has been shown to act as a viral entry inhibitor, most likely by suppressing vimentin-mediated endocytosis of virions. Targeting the increased vimentin expression on liver cells by hzVSF after infection with HBV or woodchuck hepatitis virus (WHV) was demonstrated initially. Thereafter, hzVSF safety was assessed in eight woodchucks naïve for WHV infection. Antiviral efficacy of hzVSF was evaluated subsequently in 24 chronic WHV carrier woodchucks by monotreatment with three ascending doses and in combination with tenofovir alafenamide fumarate (TAF). Consistent with the proposed blocking of WHV reinfection, intravenous hzVSF administration for 12 weeks resulted in a modest but transient reduction of viral replication and associated liver inflammation. In combination with oral TAF dosing, the antiviral effect of hzVSF was enhanced and sustained in half of the woodchucks with an antibody response to viral proteins. Thus, hzVSF safely but modestly alters chronic WHV infection in woodchucks; however, as a combination partner to TAF, its antiviral efficacy is markedly increased. The results of this preclinical study support future evaluation of this novel anti-HBV drug in patients.


Assuntos
Alanina/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Antivirais/farmacologia , Vírus da Hepatite B da Marmota/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Fígado/efeitos dos fármacos , Tenofovir/análogos & derivados , Vimentina/antagonistas & inibidores , Internalização do Vírus/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Quimioterapia Combinada , Endocitose/efeitos dos fármacos , Células Hep G2 , Hepatite B/metabolismo , Hepatite B/virologia , Vírus da Hepatite B da Marmota/patogenicidade , Interações Hospedeiro-Patógeno , Humanos , Fígado/metabolismo , Fígado/virologia , Marmota , Tenofovir/farmacologia , Vimentina/metabolismo , Carga Viral , Replicação Viral/efeitos dos fármacos
10.
Mol Cells ; 27(1): 105-11, 2009 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19214440

RESUMO

Gammaherpesvirus infection of the central nervous system (CNS) has been linked to various neurological diseases, including meningitis, encephalitis, and multiple sclerosis. However, little is known about the interactions between the virus and the CNS in vitro or in vivo. Murine gammaherpesvirus 68 (MHV-68 or (gamma)HV-68) is genetically related and biologically similar to human gammaherpesviruses, thereby providing a tractable animal model system in which to study both viral pathogenesis and replication. In the present study, we show the successful infection of cultured neuronal cells, microglia, and astrocytes with MHV-68 to various extents. Upon intracerebroventricular injection of a recombinant virus (MHV-68/LacZ) into 4-5-week-old and 9-10-week-old mice, the 4-5-week-old mice displayed high mortality within 5-7 days, while the majority of the 9-10-week-old mice survived until the end of the experimental period. Until a peak at 3-4 days post-infection, viral DNA replication and gene expression were similar in the brains of both mouse groups, but only the 9-10-week-old mice were able to subdue viral DNA replication and gene expression after 5 days post-infection. Pro-inflammatory cytokine mRNAs of tumor necrosis factor-alpha, interleukin 1beta, and interleukin 6 were highly induced in the brains of the 4-5-week-old mice, suggesting their possible contributions as neurotoxic factors in the agedependent control of MHV-68 replication of the CNS.


Assuntos
Envelhecimento/patologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/virologia , Gammaherpesvirinae/fisiologia , Infecções por Herpesviridae/virologia , Animais , Astrócitos/virologia , Linhagem Celular , Sistema Nervoso Central/metabolismo , Citocinas/genética , Citocinas/metabolismo , Suscetibilidade a Doenças , Gammaherpesvirinae/genética , Regulação Viral da Expressão Gênica , Genes Virais , Mediadores da Inflamação/metabolismo , Injeções Intraventriculares , Camundongos , Camundongos Endogâmicos BALB C , Microglia/virologia , Neurônios/virologia , Ratos , Análise de Sobrevida , Replicação Viral/fisiologia
11.
Bioelectromagnetics ; 30(1): 66-72, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18839413

RESUMO

We recently reported that continuous exposure, for 8 weeks, of extremely low frequency (ELF) magnetic field (MF) of 0.1 or 0.5 mT might induce testicular germ cell apoptosis in BALB/c mice. In that report, the ELF MF exposure did not significantly affect the body weight or testicular weight, but significantly increased the incidence of testicular germ cell death. In the present study, we aimed to further characterize the effect of a 16-week continuous exposure to ELF MF of 14 or 200 microT on testicular germ cell apoptosis in mice. There were no significant effects of MF on body weight and testosterone levels in mice. In TUNEL staining (In situ terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling), germ cells showed a significantly higher apoptotic rate in exposed mice than in sham controls (P < 0.001). TUNEL-positive cells were mainly spermatogonia. In an electron microscopic study, degenerating spermatogonia showed condensation of nuclear chromatin similar to apoptosis. These results indicate that apoptosis may be induced in spermatogenic cells in mice by continuous exposure to 60 Hz MF of 14 microT.


Assuntos
Apoptose/efeitos da radiação , Espermatozoides/fisiologia , Espermatozoides/efeitos da radiação , Testículo/fisiologia , Testículo/efeitos da radiação , Animais , Células Cultivadas , Relação Dose-Resposta à Radiação , Eletricidade , Campos Eletromagnéticos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Doses de Radiação , Espermatozoides/citologia , Testículo/citologia
12.
J Clin Diagn Res ; 10(11): DC07-DC10, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28050364

RESUMO

INTRODUCTION: Scrub Typhus (ST) is being reported from different parts of India in the recent past. However, the diagnosis and confirmation of ST cases require specific serological and molecular diagnostic tests. Both rapid and conventional ELISA tests need to be properly evaluated. AIM: Evaluation of a new ST IgM Immunochromatography (ICT) test kit (InBios Scrub Typhus Detect IgM Rapid Test) and compare it with another rapid kit, conventional ELISA kit and Weil-Felix (WF) test. MATERIALS AND METHODS: This prospective study was carried out in Mahatma Gandhi Medical College and Research Institute, Puducherry, during November 2015 to June 2016. Clinically suspected 220 ST patients were examined by a new kit, InBios Scrub Typhus Detect IgM Rapid Test, taking the conventional InBios Scrub Typhus Detect IgM ELISA as reference. Additional comparison was made with ImmuneMed Scrub Typhus Rapid, and WF test (single OXK titers ≥1:320). Statistical analysis was performed (Chi-square, Spearman's correlation and Kappa) using IBM SPSS Statistics 17 for Windows (SPSS Inc; Chicago, USA). RESULTS: Percentage Sensitivity, Specificity, Positive Predictive and Negative Predictive Values for InBios, ImmuneMed and WF were 99.25, 93.02, 95.68, 98.77; 94.87, 94.19, 96.21, 92.05 and 50.38, 95.51, 94.29, 56.67 respectively. A total of 134 patients were positive in reference standard InBios IgM ELISA. CONCLUSION: This new rapid ST IgM kit validated for the first time in India, showed good sensitivity and specificity. As a Point-of-Care (PoC) test, the kit would be helpful in both urban and remote rural parts of India.

13.
Asian J Androl ; 6(1): 29-34, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15064831

RESUMO

AIM: To evaluate the effects of 60 Hz extremely low frequency (ELF) elelctromagnetic field (EMF) exposure on germ cell apoptosis in the testis of mice. METHODS: Adult male BALB/c mice (7 weeks of age) were exposed to a 60 Hz EMF of 0.1 mT or 0.5 mT for 24 h/day. A sham-exposed group served as the control. After 8 weeks of exposure, the mice were sacrificed. Germ cell apoptosis in the testis was assessed by histopathological examination, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) and flow cytometric examination of isolated spermatogenic cells stained with 7 aminoactinomycin D (7-AAD). RESULTS: EMF exposure did not significantly affect the body and testis weights, but significantly increased the incidence of germ cell death. The distinguishing morphological feature of EMF exposure was a decrement in the number of well organized seminiferous tubules. Quantitative analysis of TUNEL-positive germ cells showed a significantly higher apoptotic rate in the 0.5 mT exposed mice than that in the sham controls (P<0.05), while the difference between the two exposed groups was insignificant. The TUNEL-positive cells were mainly spermatogonia. In flow cytometry analysis, the percentage of live cells [forward scatter count (FSC)(high)7-AAD(-)] was lower in the exposed groups than that in the controls (Figure 5A), but the decrease in viability was not statistically significant. CONCLUSION: Continuous exposure to ELF EMF may induce testicular germ cell apoptosis in mice.


Assuntos
Apoptose , Campos Eletromagnéticos/efeitos adversos , Espermatozoides/citologia , Testículo/citologia , Animais , Peso Corporal , Citometria de Fluxo , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão
14.
Biomed Res Int ; 2014: 567183, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25025060

RESUMO

The energy generated by an extremely low frequency electromagnetic field (ELF-EMF) is too weak to directly induce genotoxicity. However, it is reported that an extremely low frequency magnetic field (ELF-MF) is related to DNA strand breakage and apoptosis. The testes that conduct spermatogenesis through a dynamic cellular process involving meiosis and mitosis seem vulnerable to external stress such as heat, MF exposure, and chemical or physical agents. Nevertheless the results regarding adverse effects of ELF-EMF on human or animal reproductive functions are inconclusive. According to the guideline of the International Commission on Non-Ionizing Radiation Protection (ICNIRP; 2010) for limiting exposure to time-varying MF (1 Hz to 100 kHz), overall conclusion of epidemiologic studies has not consistently shown an association between human adverse reproductive outcomes and maternal or paternal exposure to low frequency fields. In animal studies there is no compelling evidence of causal relationship between prenatal development and ELF-MF exposure. However there is increasing evidence that EL-EMF exposure is involved with germ cell apoptosis in testes. Biophysical mechanism by which ELF-MF induces germ cell apoptosis has not been established. This review proposes the possible mechanism of germ cell apoptosis in testes induced by ELF-MF.


Assuntos
Apoptose/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Células Germinativas/efeitos da radiação , Espermatogênese/efeitos da radiação , Animais , Ciclo Celular/efeitos da radiação , Dano ao DNA/efeitos da radiação , Humanos , Campos Magnéticos , Masculino , Reprodução/efeitos da radiação
15.
J Clin Microbiol ; 41(7): 2952-60, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12843026

RESUMO

The nucleotide sequences (534 to 546 bp) of the groEL gene, which encodes the 60-kDa heat shock protein GroEL, from 15 rickettsial strains were determined and compared. In the phylogenetic tree created by the unweighted pair group method with arithmetic averages and the neighbor-joining method, rickettsial strains could be distinguished from Ehrlichia strains. Five spotted fever group strains, four typhus group strains, and six scrub typhus group (STG) strains were differentiated as distinct entities. Unlike gltA and ompA gene analyses, differentiation between members of the genus Rickettsia and the STG rickettsiae by groEL gene analysis was possible. In comparison with 16S rRNA gene analysis, the groEL gene has a higher degree of divergence among the rickettsiae. We therefore successfully developed rapid differentiation methods, PCR-restriction fragment length polymorphism analysis and a species-specific PCR, based on the groEL gene sequences. Four Korean isolates were identified by these methods and groEL gene analysis. The results suggest that the groEL gene is useful for the identification and characterization of rickettsiae.


Assuntos
Técnicas de Tipagem Bacteriana , Chaperonina 60/genética , Infecções por Rickettsia/microbiologia , Rickettsia/classificação , Análise de Sequência de DNA , DNA Ribossômico/análise , DNA Ribossômico/genética , Humanos , Coreia (Geográfico) , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Rickettsia/genética , Especificidade da Espécie
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