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1.
Front Public Health ; 11: 1186800, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37724314

RESUMO

Brucellosis is an important zoonosis and a multisystem disease. The signs and symptoms of brucellosis are not specific. In the clinical, brucellosis is often ignored and misdiagnosed. We report a case of brucellosis who was misdiagnosed as coronavirus disease 2019 (COVID-19)/influenza and received delayed treatment during strict COVID-19 control. The neglect of other diseases due to COVID-19 and empirical diagnosis and treatment by medical staff are part of the reasons for misdiagnosis. Otherwise, the normal erythrocyte sedimentation rate (ESR), increased white blood cell count (WBC), and increased neutrophil count (NEUT) of this patient was also a cause of misdiagnosis, which is an important reminder for diagnosis. For patients with the unknown origin of fever and other symptoms related to brucellosis, especially those from endemic areas of brucellosis, brucellosis screening is a priority item, and grassroots doctors should be vigilant and standardize the diagnosis and treatment based on epidemiology history, clinical manifestation, and laboratory tests according to the diagnostic criteria of brucellosis.


Assuntos
Brucelose , COVID-19 , Influenza Humana , Humanos , Animais , Influenza Humana/diagnóstico , COVID-19/diagnóstico , Zoonoses , Brucelose/diagnóstico , China
2.
Ecol Evol ; 13(8): e10387, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37529582

RESUMO

Plague is a typical natural focus disease that circulates in different ecology of vectors and reservoir hosts. We conducted genomic population and phylogenetic analyses of the Yersinia pestis collected from the 12 natural plague foci in China with more than 20 kinds of hosts and vectors. Different ecological landscapes with specific hosts, vectors, and habitat which shape various niches for Y. pestis. The phylogeographic diversity of Y. pestis in different kinds plague foci in China showed host niches adaptation. Most natural plague foci strains are region-and focus-specific, with one predominant subpopulation; but the isolates from the Qinghai-Tibet plateau harbor a higher genetic diversity than other foci. The Y. pestis from Marmota himalayana plague foci are defined as the ancestors of different populations at the root of the evolutionary tree, suggesting several different evolutionary paths to other foci. It has the largest pan-genome and widest SNP distances with most accessory genes enriched in mobilome functions (prophages, transposons). Geological barriers play an important role in the maintenance of local Y. pestis species and block the introduction of non-native strains. This study provides new insights into the control of plague outbreaks and epidemics, deepened the understanding of the evolutionary history of MHPF (M. himalayana plague focus) in China. The population structure and identify clades among different natural foci of China renewed the space cognition of the plague.

3.
Int J Infect Dis ; 135: 91-94, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37595679

RESUMO

Lysinibacillus sphaericus, as an insect pathogen, is a ubiquitous Gram-positive bacterium present in the environment. It is often considered to be contaminating bacteria. L. sphaericus has been reported to cause infectious diseases in humans relatively rarely. We report a rare case of bacteremia due to L. sphaericus in a person living with HIV, which is also the first reported case of bacteremia caused by L. sphaericus in China. L. sphaericus easily causes infection in immunocompromised individuals. We found that L. sphaericus and Lysinibacillus fusiformis could not be distinguished by their 16S ribosomal RNA gene sequence. We performed a genome-wide analysis of the isolated strains of this case and predicted the virulence factors. Finally, L. sphaericus was confirmed. According to antimicrobial susceptibility test, the strain was found to be sensitive to levofloxacin and vancomycin but resistant to penicillin. Greater attention to L. sphaericus infection should be paid and immunocompromised populations should be protected from L. sphaericus infection.

4.
Am J Trop Med Hyg ; 108(6): 1201-1203, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37127273

RESUMO

Brucellosis is a common zoonotic disease. For this study, the residents of Akesai Kazak Autonomous County, located in the high altitude of the Altun Mountains region of Gansu Province, were selected. These people rely on traditional animal husbandry for their main income. The prevalence of brucellosis and the change of antibody titer in this high-risk population were analyzed, and information on the epidemic in animals in the county was obtained from data records. One hundred ninety-nine persons were screened and 240 serum samples were collected. Eight persons and 27 serum samples were positive based on the rose bengal plate test, and seven persons were confirmed positive by standard agglutination test; 16,000 sheep were tested, of which 130 from nine different households were serum antibody positive. The results indicate that brucellosis seroprevalence increased among sheep and high-risk populations, and the occurrence of cases corresponded to the epidemic among animals. The incidence of human brucellosis was closely related to occupation, and the cases were mainly distributed among herdsmen and butchers. Most cases were asymptomatic or mild, and the serum antibody titers showed a high initial titer but a rapid decline in young cases, whereas those in older cases were relatively low but showed a slow decline.


Assuntos
Brucelose , Humanos , Animais , Ovinos , Idoso , Estudos Soroepidemiológicos , Brucelose/diagnóstico , Brucelose/epidemiologia , Brucelose/veterinária , Zoonoses/epidemiologia , Fatores de Risco , China/epidemiologia
5.
Front Public Health ; 10: 990218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466443

RESUMO

The Altun Mountains are among the most active regions of Marmota himalayana plague foci of the Qinghai-Tibet Plateau where animal plague is prevalent, whereas only three human cases have been found since 1960. Animal husbandry is the main income for the local economy; brucellosis appears sometimes in animals and less often in humans. In this study, a retrospective investigation of plague and brucellosis seroprevalence among humans and animals was conducted to improve prevention and control measures for the two diseases. Animal and human sera were collected for routine surveillance from 2018 to 2021 and screened for plague and brucellosis. Yersinia pestis F1 antibody was preliminarily screened by the colloidal gold method at the monitoring site to identify previous infections with positive serology. Previous plague infection was found in 3.2% (14/432) of the studied human population having close contact with livestock, which indicates evidence of exposure to the Yersinia antigen (dead or live pathogenic materials) in the Altun Mountains. Seroprevalence of brucellosis was higher in camels (6.2%) and sheepdogs (1.8%) than in other livestock such as cattle and sheep, suggesting a possible transmission route from secondary host animals to humans.


Assuntos
Brucelose , Peste , Bovinos , Humanos , Animais , Ovinos , Marmota , Peste/epidemiologia , Peste/veterinária , Estudos Soroepidemiológicos , Estudos Retrospectivos , Tibet/epidemiologia , Brucelose/epidemiologia , Brucelose/veterinária
6.
Microbiol Spectr ; 10(6): e0166222, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36219109

RESUMO

This study analyzed the epidemiological characteristics of 3,464 human plague cases and the distribution pattern of 4,968 Yersinia pestis isolates from humans, hosts, and vector insects from 1950 to 2020 among two natural plague foci in Yunnan Province, China. These foci include the Rattus flavipectus plague focus of the Yunnan, Guangdong, and Fujian provinces and the Apodemus chevrieri-Eothenomys miletus plague focus of the highlands of northwestern Yunnan Province. The case fatality rate for plague in humans was 18.39% (637/3,464), and the total isolation rate of Y. pestis was 0.17% (4,968/2,975,288). Despite that the frequency of human cases declined rapidly, the animal plague fluctuated greatly, alternating between activity and inactivity in these foci. The tendency among human cases can be divided into 4 stages, 1950 to 1955, 1956 to 1989, 1990 to 2005, and 2006 to 2020. Bubonic plague accounted for the majority of cases in Yunnan, where pneumonic and septicemic plague rarely occurred. The natural plague foci have been in a relatively active state due to the stability of local ecology. Dense human population and frequent contact with host animals contribute to the high risk of human infection. This study systematically analyzed the epidemic pattern of human plague and the distribution characteristics of Y. pestis in the natural plague foci in Yunnan, providing a scientific basis for further development and adjustment of plague prevention and control strategies. IMPORTANCE Yunnan is the origin of the third plague pandemic. The analysis of human and animal plague characteristics of plague foci in Yunnan enlightens the prevention and control of the next plague pandemics. The plague characteristics of Yunnan show that human plague occurred when animal plague reached a certain scale, and strengthened surveillance of animal plague and reducing the density of host animals and transmission vectors contribute to the prevention and control of human plague outbreaks. The phenomenon of alternation between the resting period and active period of plague foci in Yunnan further proves the endogenous preservation mechanism of plague.


Assuntos
Peste , Yersinia pestis , Ratos , Animais , Humanos , Peste/epidemiologia , Peste/veterinária , China/epidemiologia , Surtos de Doenças , Pandemias
7.
Vector Borne Zoonotic Dis ; 22(8): 410-418, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35787155

RESUMO

In April 2021, a plague outbreak was identified within one Marmota himalayana family shortly after emerging from hibernation, during plague surveillance in the M. himalayana plague foci of the Qinghai-Tibet Plateau. A total of five marmots were found dead of Yersinia pestis near the same burrow; one live marmot was positive of Y. pestis fraction 1 (F1) antibody. Comparative genome analysis shows that few single nucleotide polymorphisms were detected among the nine strains, indicating the same origin of the outbreak. The survived marmot shows a high titer of F1 antibody, higher than the mean titer of all marmots during the 2021 monitoring period (W = 391.00, Z = 2.81, p < 0.01). Marmots live with Y. pestis during hibernation when the pathogen is inhibited by hypothermia. But they wake up during or just after hibernation with body temperature rising to 37°C, when Y. pestis goes through optimal growth temperature, increases virulence, and causes death in marmots. A previous report has shown human plague cases caused by excavating marmots during winter; combined, this study shows the high risk of hibernation marmot carrying Y. pestis. This analysis provides new insights into the transmission of the highly virulent Y. pestis in M. himalayana plague foci and drives further effort upon plague control during hibernation.


Assuntos
Hibernação , Peste , Doenças dos Roedores , Yersinia pestis , Animais , Surtos de Doenças , Humanos , Marmota , Peste/epidemiologia , Peste/veterinária , Doenças dos Roedores/epidemiologia , Yersinia pestis/genética
8.
Front Public Health ; 10: 910872, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692330

RESUMO

Introduction: The Qinghai-Tibet Plateau is considered the most plague-heavy region in China, and skinning and eating marmots (Marmota himalayana) are understood to be the main exposure factors to plague. Yersinia pestis is relatively inactive during marmots' hibernation period. However, this case report shows plague infection risk is not reduced but rather increased during the marmot hibernation period if plague exposure is not brought under control. Case Presentation: The patient was a 45-year-old man who presented with high fever, swelling of axillary lymph nodes, and existing hand wounds on his right side. Y. pestis was isolated from his blood and lymphatic fluid. Hence, the patient was diagnosed with a confirmed case of bubonic plague. Later, his condition progressed to septicemic plague. Plague exposure through wounds and delays in appropriate treatment might have contributed to plague progression. Conclusion: This case report reveals that excavating a hibernating marmot is a significant transmission route of plague. Plague prevention and control measures are priority needs during the marmot hibernation period.


Assuntos
Marmota , Yersinia pestis , Animais , China , Humanos , Masculino , Pessoa de Meia-Idade
9.
BMC Genomics ; 23(1): 335, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35490230

RESUMO

BACKGROUND: Human granulocytic anaplasmosis is a tick-borne zoonotic disease caused by Anaplasma phagocytophilum. Coinfections with A. phagocytophilum and other tick-borne pathogens are reported frequently, whereas the relationship between A. phagocytophilum and flea-borne Yersnia pestis is rarely concerned. RESULTS: A. phagocytophilum and Yersnia pestis were discovered within a Marmota himalayana found dead in the environment, as determined by 16S ribosomal rRNA sequencing. Comparative genomic analyses of marmot-derived A. phagocytophilum isolate demonstrated its similarities and a geographic isolation from other global strains. The 16S rRNA gene and GroEL amino acid sequence identity rates between marmot-derived A. phagocytophilum (JAHLEX000000000) and reference strain HZ (CP000235.1) are 99.73% (1490/1494) and 99.82% (549/550), respectively. 16S rRNA and groESL gene screenings show that A. phagocytophilum is widely distributed in marmots; the bacterium was more common in marmots found dead (24.59%, 15/61) than in captured marmots (19.21%, 29/151). We found a higher Y. pestis isolation rate in dead marmots harboring A. phagocytophilum than in those without it (2 = 4.047, p < 0.05). Marmot-derived A. phagocytophilum was able to live in L929 cells and BALB/c mice but did not propagate well. CONCLUSIONS: In this study, A. phagocytophilum was identified for the first time in Marmota himalayana, a predominant Yersinia pestis host. Our results provide initial evidence for M. himalayana being a reservoir for A. phagocytophilum; moreover, we found with the presence of A. phagocytophilum, marmots may be more vulnerable to plague. Humans are at risk for co-infection with both pathogens by exposure to such marmots.


Assuntos
Anaplasma phagocytophilum , Anaplasmose , Carrapatos , Anaplasma phagocytophilum/genética , Anaplasmose/microbiologia , Animais , Marmota/genética , Camundongos , RNA Ribossômico 16S/genética , Carrapatos/microbiologia
10.
Redox Biol ; 50: 102246, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35086002

RESUMO

Aquaporin-9 (AQP9) is an aquaglyceroporin strongly expressed in the basolateral membrane of hepatocytes facing the sinusoids. AQP9 is permeable to hydrogen peroxide (H2O2) and glycerol as well as to water. Here, we report impaired liver regeneration in AQP9-/- mice which involves altered steady-state H2O2 concentration and glucose metabolism in hepatocytes. AQP9-/- mice showed remarkably delayed liver regeneration and increased mortality following 70% or 90% partial hepatectomy. Compared to AQP9+/+ littermates, AQP9-/- mice showed significantly greater hepatic H2O2 concentration and more severe liver injury. Fluorescence measurements indicated impaired H2O2 transport across plasma membrane of primary cultured hepatocytes from AQP9-/- mice, supporting the hypothesis that AQP9 deficiency results in H2O2 accumulation and oxidative injury in regenerating liver because of reduced export of intracellular H2O2 from hepatocytes. The H2O2 overload in AQP9-/- hepatocytes reduced PI3K-Akt and insulin signaling, inhibited autophagy and promoted apoptosis, resulting in impaired proliferation and increased cell death. In addition, hepatocytes from AQP9-/- mice had low liver glycerol and high blood glycerol levels, suggesting decreased glycerol uptake and gluconeogenesis in AQP9-/- hepatocytes. Adeno-associated virus (AAV)-mediated expression of hepatic expression of aquaglyceroporins AQP9 and AQP3 in AQP9-/- mice, but not water-selective channel AQP4, fully rescued the impaired liver regeneration phenotype as well as the oxidative injury and abnormal glucose metabolism. Our data revealed a pivotal role of AQP9 in liver regeneration by regulating hepatocyte H2O2 homeostasis and glucose metabolism, suggesting AQP9 as a novel target to enhance liver regeneration following injury, surgical resection or transplantation.


Assuntos
Aquaporinas , Regeneração Hepática , Animais , Aquaporinas/genética , Aquaporinas/metabolismo , Hepatectomia , Hepatócitos/metabolismo , Peróxido de Hidrogênio/metabolismo , Fígado/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo
11.
Emerg Infect Dis ; 27(10): 2544-2553, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34545784

RESUMO

We analyzed epidemiologic characteristics and distribution of 1,067 human plague cases and 5,958 Yersinia pestis isolates collected from humans, host animals, and insect vectors during 1950-2019 in 4 Marmota plague foci in China. The case-fatality rate for plague in humans was 68.88%; the overall trend slowly decreased over time but fluctuated greatly. Most human cases (98.31%) and isolates (82.06%) identified from any source were from the Marmota himalayana plague focus. The tendency among human cases could be divided into 3 stages: 1950-1969, 1970-2003, and 2004-2019. The Marmota sibirica plague focus has not had identified human cases nor isolates since 1926. However, in the other 3 foci, Y. pestis continues to circulate among animal hosts; ecologic factors might affect local Y. pestis activity. Marmota plague foci are active in China, and the epidemic boundary is constantly expanding, posing a potential threat to domestic and global public health.


Assuntos
Peste , Yersinia pestis , Animais , China/epidemiologia , Humanos , Insetos Vetores , Marmota , Peste/epidemiologia
12.
Front Cell Infect Microbiol ; 11: 700322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307197

RESUMO

A lytic Yersinia pestis phage vB_YpP-YepMm (also named YepMm for briefly) was first isolated from the bone marrow of a Marmota himalayana who died of natural causes on the Qinghai-Tibet plateau in China. Based on its morphologic (isometric hexagonal head and short non-contractile conical tail) and genomic features, we classified it as belonging to the Podoviridae family. At the MOI of 10, YepMm reached maximum titers; and the one-step growth curve showed that the incubation period of the phage was about 10 min, the rise phase was about 80 min, and the lysis amount of the phage during the lysis period of 80 min was about 187 PFU/cell. The genome of the bacteriophage YepMm had nucleotide-sequence similarity of 99.99% to that of the Y. pestis bacteriophage Yep-phi characterized previously. Analyses of the biological characters showed that YepMm has a short latent period, strong lysis, and a broader lysis spectrum. It could infect Y. pestis, highly pathogenic bioserotype 1B/O:8 Y. enterocolitica, as well as serotype O:1b Y. pseudotuberculosis-the ancestor of Y. pestis. It could be further developed as an important biocontrol agent in pathogenic Yersinia spp. infection.


Assuntos
Bacteriófagos , Peste , Yersinia pestis , Animais , Bacteriófagos/genética , Medula Óssea , China , Marmota , Tibet
13.
Antibiotics (Basel) ; 10(3)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669137

RESUMO

Antibiotic resistance has become a global public health concern. To determine the distribution characteristics of mcr and blaNDM in China, gene screening was conducted directly from gut specimens sourced from livestock and poultry, poultry environments, human diarrhea patients, and wild animals from 10 regions, between 2010-2020. The positive rate was 5.09% (356/6991) for mcr and 0.41% (29/6991) for blaNDM, as detected in gut specimens from seven regions, throughout 2010 to 2019, but not detected in 2020. The detection rate of mcr showed significant differences among various sources: livestock and poultry (14.81%) > diarrhea patients (1.43%) > wild animals (0.36%). The detection rate of blaNDM was also higher in livestock and poultry (0.88%) than in diarrhea patients (0.17%), and this was undetected in wildlife. This is consistent with the relatively high detection rate of multiple mcr genotypes in livestock and poultry. All instances of coexistence of the mcr-1 and blaNDM genes, as well as coexistence of mcr genotypes within single specimens, and most new mcr subtypes came from livestock, and poultry environments. Our study indicates that the emergence of mcr and blaNDM genes in China is closely related to the selective pressure of carbapenem and polymyxin. The gene-based strategy is proposed to identify more resistance genes of concern, possibly providing guidance for the prevention and control of antimicrobial resistance dissemination.

14.
PLoS One ; 16(2): e0247418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33617547

RESUMO

The increasing prevalence of carbapenem-resistant Acinetobacter baumannii (CRAB) caused nosocomial infections generate significant comorbidity and can cause death among patients. Current treatment options are limited. These infections pose great difficulties for infection control and clinical treatment. To identify the antimicrobial resistance, carbapenemases and genetic relatedness of Acinetobacter baumannii isolates from cerebrospinal fluid (CSF) and blood, a total of 50 nonrepetitive CSF isolates and 44 blood isolates were collected. The resistance phenotypes were determined, and polymerase chain reaction (PCR) was performed to examine the mechanisms of carbapenem resistance. Finally, multilocus sequence typing (MLST) was conducted to determine the genetic relatedness of these isolates. It was observed that 88 of the 94 collected isolates were resistant to imipenem or meropenem. Among them, the blaOXA-23 gene was the most prevalent carbapenemase gene, with an observed detection rate of 91.5% (86/94), followed by the blaOXA-24 gene with a 2.1% detection rate (2/94). Among all carbapenem-resistant Acinetobacter baumannii (CRAB) observations, isolates with the blaOXA-23 gene were resistant to both imipenem and meropenem. Interestingly, isolates positive for the blaOXA-24 gene but negative for the blaOXA-23 gene showed an imipenem-sensitive but meropenem-resistant phenotype. The MLST analysis identified 21 different sequence types (STs), with ST195, ST540 and ST208 most frequently detected (25.5%, 12.8% and 11.7%, respectively). 80 of the 94 isolates (85.1%) were clustered into CC92 which showed a carbapenem resistance phenotype (except AB13). Five novel STs were detected, and most of them belong to CRAB. In conclusion, these findings provide additional observations and epidemiological data of CSF and blood A. baumannii strains, which may improve future infection-control measures and aid in potential clinical treatments in hospitals and other clinical settings.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/uso terapêutico , Sangue/microbiologia , Líquido Cefalorraquidiano/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Acinetobacter baumannii/genética , Proteínas de Bactérias/genética , Carbapenêmicos/uso terapêutico , Humanos , Imipenem/uso terapêutico , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana/métodos , beta-Lactamases/genética
15.
Front Microbiol ; 11: 121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117144

RESUMO

Currently, Gram-negative bacteria have developed multidrug and broad-spectrum drug resistance, and the numbers of species and strains carrying mcr or bla NDM genes are increasing. In this study, mcr-1 and bla NDM distribution of 12,858 Gram-negative bacteria isolated from wildlife, patients, livestock, poultry and environment in 14 provinces of China from 2010 to 2019 and the antibiotics resistance in regard to polymyxins (polymyxin B and colistin) and carbapenems of positive strains were investigated. A total of 70 strains of 10 species carried the mcr-1 gene, positive rates of patients, livestock and poultry, and environmental strains were 0.62% (36/5,828), 4.07% (29/712), 5.43% (5/92), respectively. Six strains of 3 species carrying the bla NDM gene all came from patients 0.10% (6/5,828). Two new mcr-1 gene variants (GenBank: MK965883, MK965884) were identified, one of which contains premature stop codon. The drug susceptibility results showed that all mcr-1 carriers were sensitive to carbapenems, among which, 66 strains were resistant and 4 were sensitive to polymyxins. The strains with the bla NDM gene had different degrees of resistance to carbapenems and were sensitive to polymyxins. The findings that species carrying mcr-1 or bla NDM genes were limited and mostly normal flora of opportunistic or low pathogenic organisms indicated that transfer of mcr-1 and bla NDM genes between bacteria was relatively limited in China. The none detection among wildlife compared with other sources supports the speculation that the emergence of and increase in polymyxins and carbapenem-resistant strains was mainly related to the selective pressure of antibiotics.

16.
Onco Targets Ther ; 11: 7031-7040, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410360

RESUMO

BACKGROUND: Sesquiterpene lactones are plant-derived, natural, bioactive molecules often used against inflammatory diseases in traditional Chinese medicines. Recently, sesquiterpene lactones have been reported to exhibit potent anticancer activity. In the present study, we have investigated the anticancer activity of Brevilin A, a sesquiterpene lactone component of Centipeda minima, against U87 glioblastoma cells. MATERIALS AND METHODS: The cell proliferation was determined by MTT assay. Cell morphological changes were observed by phase-contrast microscopy. Flow cytometry was used to measure apoptosis. Glutathione (GSH), ROS generation, and mitochondrial membrane potential were measured using commercially available kits. The expression of proteins was measured by Western blotting analysis. RESULTS: Brevilin A inhibited the proliferation of, and induced severe morphological changes and apoptotic cell death in, U87 glioblastoma cells in a dose-dependent manner. Further mechanistic study revealed that Brevilin A induces oxidative stress, as evident from ROS generation, GSH depletion, and increased phosphorylation of stress-activated proteins p38 and JNK. Furthermore, Brevilin A bcl-xl/bak ratio, decreased mitochondrial membrane potential and induced cytochrome c release from mitochondria into cytosol in a dose-dependent manner. Finally, Brevilin A decreased the expression of Xiap and increased the expression of cleaved forms of caspase-9 and -3 and PARP in a dose-dependent manner. CONCLUSION: Collective findings demonstrated that Brevilin A is a potent, anticancer, bioactive molecule and it effectively induces apoptosis in U87 glioblastoma cells, which is associated with induction of oxidative stress and mitochondrial dysfunction.

17.
Foodborne Pathog Dis ; 14(6): 333-340, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28537439

RESUMO

BACKGROUND: Enterotoxigenic Escherichia coli (ETEC) is one of the major causes of infectious diarrhea in developing countries. This study aimed to characterize the prevalence and phenotypic and genotypic features of ETEC isolates from Shenzhen, China. METHODS: ETEC isolates were obtained from acute diarrheal patients and evaluated for enterotoxin, classical colonization factors (CFs), serotypes, antimicrobial susceptibility, and multilocus sequencing typing (MLST). RESULTS: A total of 168 (1.3%) ETEC strains were isolated from 13,324 diarrheal outpatients during 2009 and 2014. A vast majority of ETEC-infected patients (82.1%) belonged to the age ranging 20-59 years and only six patients were children aged <5 years. Heat-stable toxin (ST) was most frequently detected (81.5%), followed by heat-labile toxin (LT) (13.1%). One or multiple colonization factors (CFs) were identified in 91 ETEC strains (54.2%). The most frequently detected CF was CS6 (with or without other CFs) (84/91), followed by CS21 (14/91). The most common serotype was O159:H34 (n = 36), followed by O148:H28 (n = 25) and O27:H7 (n = 17). High resistant rate was observed to nalidixic acid (77.4%), cephalothin (41.7%), ampicillin (34.5%), and tetracycline (21.4%). Antimicrobial resistance profiles differed among different serogroups. Sequence type (ST) 10 complex, integrated with connected ST218, ST48, ST4, and ST1312 subgroups, covered 73 (43.5%) isolates. CONCLUSIONS: ETEC isolates in Shenzhen of China appeared highly diverse, yet some isolates belonged to well-defined clonal groups sharing a unique set of virulence factors, serotypes, and MLST sequence types. Facing the challenge of ETEC antigenic diversity and geographic variation, novel molecules and/or classical antigens designed by novel strategies might contribute to ETEC vaccine development.


Assuntos
Diarreia/microbiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampicilina/farmacologia , Antibacterianos/farmacologia , Toxinas Bacterianas/isolamento & purificação , Cefalotina/farmacologia , Criança , Pré-Escolar , China/epidemiologia , DNA Bacteriano/genética , Diarreia/epidemiologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli Enterotoxigênica/genética , Feminino , Genes Bacterianos , Técnicas de Genotipagem , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Ácido Nalidíxico/farmacologia , Tetraciclina/farmacologia , Adulto Jovem
18.
Wei Sheng Yan Jiu ; 40(4): 514-6, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21861361

RESUMO

OBJECTIVE: To develop real-time PCR assay based on modified molecular beacon for simultaneous detection of S. choleraesuis and S. paratyphi C. The established method was applied to the rapid detection of S. choleraesuis in food and stool samples of food poisoning, and then was applied to the identification of Salmonella C. METHODS: Based on the sequences (CP000857.1) published in GenBank, Two sets of primers and modified molecular beacon were designed. The Real-time PCR assay for the simultaneous detection of S. paratyphi C and S. choleraesuis was developed with optimized PCR procedures and PCR components, while other 11 different bacterial species were as the control. Then the sensitivity and specificity of the assay were tested using 77 Samonella strains. The assay was applied to the detection of 70 food samples. RESULTS: The limit of detection achieved was 10 fg/reaction or 20 CUF/reaction, Only Salmonella paratyphi C and Salmonella choleraesuis strains generated fluorescent signals. No cross-reaction was observed with other 11 bacterium, the sensitivity and specificity were both 100%. No samples among 70 food samples were found Salmonella positive by both real-time PCR assay and traditional culture method. It could be finished within 2 hours from template preparation to detection and the overall test would be finished within one day. CONCLUSION: The real-time PCR assay was rapid, sensitive and specific. It could be applied to the rapid diagnosis of S. paratyphi C and S. choleraesuis in food and stool samples of food poisoning and the identification of Salmonella C to guarantee food safety.


Assuntos
Microbiologia de Alimentos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Intoxicação Alimentar por Salmonella/microbiologia , Salmonella arizonae/isolamento & purificação , Salmonella paratyphi C/isolamento & purificação , Animais , Contaminação de Alimentos/análise , Salmonella arizonae/genética , Salmonella paratyphi C/genética , Sensibilidade e Especificidade , Suínos
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