RESUMO
Information on causative diarrheal pathogens and their associated antimicrobial susceptibility remains limited for Cambodia. This study describes antimicrobial resistance patterns for Shigella and nontyphoidal Salmonella isolates collected in Cambodia over a 5-year period. Multidrug resistance was shown in 98% of Shigella isolates, with 70%, 11%, and 29% of isolates being resistant to fluoroquinolones, azithromycin, and cephalosporin, respectively. As many as 11% of Shigella isolates were resistant to nearly all oral and parenteral drugs typically used for shigellosis, demonstrating extreme drug resistance phenotypes. Although a vast majority of nontyphoidal Salmonella isolates remained susceptible to cephalosporins (99%) and macrolides (98%), decreased susceptibility to ciprofloxacin was found in 67% of isolates, which is notably higher than previous reports. In conclusion, increasing antimicrobial resistance of Shigella and nontyphoidal Salmonella is a major concern for selecting empirical treatment of acute infectious diarrhea in Cambodia. Treatment practices should be updated and follow local antimicrobial resistance data for the identified pathogens.
Assuntos
Shigella , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camboja , Diarreia/tratamento farmacológico , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana , SalmonellaRESUMO
BACKGROUND/PURPOSE: Betel quid (BQ) chewing is popular in Taiwan and many other countries. There are about 200-600 million BQ chewers in the world. BQ chewing is one major risk factor of oral cancer and oral submucous fibrosis (OSF). While areca nut (AN), a main component of BQ, exhibits genotoxicity, its transformation capacity and its role in the initiation and promotion stages of carcinogenesis are not fully clear. METHODS: Mouse C3H10T1/2 cells were exposed to AN extract (ANE) for 24 hours. Cytotoxicity was evaluated by colony forming efficiency. For the transformation assay, C3H10T1/2 cells were exposed to ANE for 24 hours and then incubated in medium with/without 12-O-tetradecanolylphorbol-13-acetate (TPA; a tumor promoter) for 42 days. Cells were stained with Giemsa and type II and type III transformed foci were counted for analysis of the transformation capacity of ANE. RESULTS: ANE exhibited cytotoxicity to C3H10T/12 cells at concentrations higher than 320 µg/mL as shown by a decrease in colony numbers. ANE (80-640 µg/mL) alone mildly stimulated the transformed foci formation (p > 0.05). In the presence of TPA, ANE (80-640 µg/mL) markedly stimulated the transformed foci formation. The percentage of dishes with foci increased from 0% in controls to 20% in ANE (80 µg/mL and 320 µg/mL)-treated groups and further increased to 65-94% in ANE plus TPA groups. CONCLUSION: These results indicate that ANE is a weak complete carcinogen. ANE is an effective tumor initiator and can induce malignant transformation of C3H10T1/2 cells in the presence of a tumor promoter. ANE may be involved in multistep chemical carcinogenesis by its malignant transformation capacity.
Assuntos
Areca/química , Nozes/química , Extratos Vegetais/toxicidade , Células-Tronco Pluripotentes/efeitos dos fármacos , Animais , Linhagem Celular , Camundongos , Neoplasias Bucais/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo , TaiwanRESUMO
BACKGROUND/PURPOSE: In Taiwan, the combination of betel quid chewing, alcohol consumption, and smoking habits increases oral cancer risk by 123-fold compared to persons without these habits. Lymphocyte populations in patients may potentially affect the malignant transformation of oral precancer. METHODS: A total of 28 patients with oral precancer from our previous cohort were enrolled in this study, and their personal information and oral habits were documented. Their lymphocyte populations (CD4+, CD8+, CD19+, and CD56+) and activation markers (CD25 and CD69) were determined by flow cytometry from 1999 to 2004. After follow up till December 2014, data of patients with/without malignant transformation were recorded, and the relation between oral habits and percentage of initial lymphocyte markers was evaluated using the Student t test and Fisher's exact test. RESULTS: Ten precancer patients developed oral squamous cell carcinoma with a mean period of malignant transformation of 6.8 ± 2.1 years. Patients with malignant transformation had a mean age of 48.4 ± 5.0 years (n = 10), relatively more than that of patients without malignant transformation (41.6 ± 6.3 years, n = 18) (p < 0.05). An increase was noted in the population of peripheral blood mononuclear cells expressing CD4+CD69+, CD19+CD69+, and CD56+CD69+ (p < 0.05) in precancer patients with malignant transformation. Alcohol consumption showed an association with the malignant transformation of patients with precancer (p = 0.030), whereas betel quid and smoking showed little effect. CONCLUSION: These results suggest that age, alcohol consumption, and early activation of T cells, B cells, and natural killer cells are crucial in the malignant transformation of oral precancer. Analysis of patient's lymphocyte populations may help predict the malignant transformation of oral precancer.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Areca/efeitos adversos , Carcinoma de Células Escamosas/epidemiologia , Subpopulações de Linfócitos/imunologia , Neoplasias Bucais/epidemiologia , Fumar/epidemiologia , Adulto , Linfócitos B/imunologia , Biomarcadores/análise , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/etiologia , Taiwan/epidemiologiaRESUMO
Human infections with influenza A(H5N1) virus in Cambodia increased sharply during 2013. Molecular characterization of viruses detected in clinical specimens from human cases revealed the presence of mutations associated with the alteration of receptor-binding specificity (K189R, Q222L) and respiratory droplet transmission in ferrets (N220K with Q222L). Discovery of quasispecies at position 222 (Q/L), in addition to the absence of the mutations in poultry/environmental samples, suggested that the mutations occurred during human infection and did not transmit further.
Assuntos
Marcadores Genéticos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Humana/virologia , Ligação Viral , Adolescente , Adulto , Substituição de Aminoácidos , Camboja , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Lactente , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Filogenia , Análise de Sequência de DNARESUMO
This study compared the pathogenicity of monokaryotic (monokaryon) and dikaryotic (dikaryon) mycelia of the oil palm pathogen Ganoderma boninense via metabolomics approach. Ethyl acetate crude extracts of monokaryon and dikaryon were analysed by liquid chromatography quadrupole/time-of-flight-mass spectrometry (LC-Q/TOF-MS) coupled with multivariate data analysis using MetaboAnalyst. The mummichog algorithm was also used to identify the functional activities of monokaryon and dikaryon without a priori identification of all their secondary metabolites. Results revealed that monokaryon produced lesser fungal metabolites than dikaryon, suggesting that monokaryon had a lower possibility of inducing plant infection. These findings were further supported by the identified functional activities. Monokaryon exhibits tyrosine, phenylalanine, and tryptophan metabolism, which are important for fungal growth and development and to produce toxin precursors. In contrast, dikaryon exhibits the metabolism of cysteine and methionine, arginine and proline, and phenylalanine, which are important for fungal growth, development, virulence, and pathogenicity. As such, monokaryon is rendered non-pathogenic as it produces growth metabolites and toxin precursors, whereas dikaryon is pathogenic as it produces metabolites that are involved in fungal growth and pathogenicity. The LC-MS-based metabolomics approach contributes significantly to our understanding of the pathogenesis of Ganoderma boninense, which is essential for disease management in oil palm plantations.
Assuntos
Ganoderma , Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Virulência , Cromatografia Líquida , FenilalaninaRESUMO
In resource-scarce settings, melioidosis is associated with up to 80% mortality. Studies of melioidosis in Cambodia report primarily on pediatric populations with localized infection; however, literature describing Cambodian adults with severe melioidosis is lacking. We present a case series of 35 adults with sequence-confirmed Burkholderia pseudomallei bacteremia presenting to a provincial referral hospital in rural Cambodia. More than 90% of the patients had diabetes, an important risk factor for developing melioidosis. Inappropriate antimicrobial therapy was significantly associated with lower odds of survival. Improved diagnostic testing and greater access to first-line antibiotics for acute melioidosis treatment present potential targets for intervention to reduce mortality associated with this disease in resource-limited settings.
Assuntos
Antibacterianos , Bacteriemia , Burkholderia pseudomallei , Melioidose , Humanos , Melioidose/tratamento farmacológico , Melioidose/mortalidade , Melioidose/epidemiologia , Melioidose/microbiologia , Burkholderia pseudomallei/isolamento & purificação , Burkholderia pseudomallei/efeitos dos fármacos , Camboja/epidemiologia , Fatores de Risco , Masculino , Feminino , Estudos Retrospectivos , Adulto , Bacteriemia/mortalidade , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Pessoa de Meia-Idade , Antibacterianos/uso terapêutico , Idoso , Adulto JovemRESUMO
The duration of humoral and cellular immune memory following SARS-CoV-2 infection in populations in least developed countries remains understudied but is key to overcome the current SARS-CoV-2 pandemic. Sixty-four Cambodian individuals with laboratory-confirmed infection with asymptomatic or mild/moderate clinical presentation were evaluated for Spike (S)-binding and neutralizing antibodies and antibody effector functions during acute phase of infection and at 6-9 months follow-up. Antigen-specific B cells, CD4+ and CD8+ T cells were characterized, and T cells were interrogated for functionality at late convalescence. Anti-S antibody titers decreased over time, but effector functions mediated by S-specific antibodies remained stable. S- and nucleocapsid (N)-specific B cells could be detected in late convalescence in the activated memory B cell compartment and are mostly IgG+. CD4+ and CD8+ T cell immune memory was maintained to S and membrane (M) protein. Asymptomatic infection resulted in decreased antibody-dependent cellular cytotoxicity (ADCC) and frequency of SARS-CoV-2-specific CD4+ T cells at late convalescence. Whereas anti-S antibodies correlated with S-specific B cells, there was no correlation between T cell response and humoral immune memory. Hence, all aspects of a protective immune response are maintained up to nine months after SARS-CoV-2 infection and in the absence of re-infection.
Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , SARS-CoV-2/imunologia , Linfócitos B/imunologia , COVID-19/patologia , Camboja , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Fosfoproteínas/imunologia , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
INTRODUCTION: The burden of influenza in Cambodia is not well known, but it would be useful for understanding the impact of seasonal epidemics and pandemics and to design appropriate policies for influenza prevention and control. The severe acute respiratory infection (SARI) surveillance system in Cambodia was used to estimate the national burden of SARI hospitalizations in Cambodia. METHODS: We estimated age-specific influenza-associated SARI hospitalization rates in three sentinel sites in Svay Rieng, Siem Reap and Kampong Cham provinces. We used influenza-associated SARI surveillance data for one year to estimate the numerator and hospital admission surveys to estimate the population denominator for each site. A national influenza-associated SARI hospitalization rate was calculated using the pooled influenza-associated SARI hospitalizations for all sites as a numerator and the pooled catchment population of all sites as denominator. National influenza-associated SARI case counts were estimated by applying hospitalization rates to the national population. RESULTS: The national annual rates of influenza-associated hospitalizations per 100 000 population was highest for the two youngest age groups at 323 for < 1 year and 196 for 1-4 years. We estimated 7547 influenza-associated hospitalizations for Cambodia with almost half of these represented by children younger than 5 years. DISCUSSION: We present national estimates of influenza-associated SARI hospitalization rates for Cambodia based on sentinel surveillance data from three sites. The results of this study indicate that the highest burden of severe influenza infection is borne by the younger age groups. These findings can be used to guide future strategies to reduce influenza morbidity.
Assuntos
Efeitos Psicossociais da Doença , Hospitalização/estatística & dados numéricos , Influenza Humana/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Camboja/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Vigilância de Evento Sentinela , Adulto JovemRESUMO
BACKGROUND: In Cambodia, epidemiology and disease burden of leptospirosis were not addressed as they do not have an existing surveillance system and have limitations on their laboratory diagnosis. OBJECTIVE: Define the existence of leptospirosis and determine the antibodies to serovars of leptospires in Cambodia. MATERIAL AND METHOD: One hundred and twenty-one suspected cases of leptospirosis were enrolled in this cross-sectional study, between September 8 and November 30, 2003 from Takeo Provincial Hospital in Doun Keo District, Cambodia. RESULTS: Common clinical manifestations were fever (96%), headache (92%), and myalgia (87%). Common risk behaviors were throwing garbage on the ground (84%), pulling out sprouts (77%), fertilizing (49%), and plowing (47%). Microscopic agglutination test result confirmed four cases and polymerase chain reaction test result confirmed seven cases. Two cases each showed antibodies to serovars Javanica and Australis. An estimated annual incidence of leptospirosis in Takeo province was 7.65 per 100,000 populations. Further studies to define epidemiology and burden of disease are needed. CONCLUSION: Increasing awareness and knowledge on leptospirosis among people are necessary to decrease the impact of leptospirosis in Cambodia.
Assuntos
Leptospirose/epidemiologia , Adolescente , Adulto , Anticorpos/sangue , Camboja/epidemiologia , Feminino , Humanos , Leptospirose/sangue , Masculino , Pessoa de Meia-IdadeRESUMO
In Cambodia, the first detection of HPAI H5N1 virus in birds occurred in January 2004 and since then there have been 33 outbreaks in poultry while 21 human cases were reported. The origin and dynamics of these epizootics in Cambodia remain unclear. In this work we used a range of bioinformatics methods to analyze the Cambodian virus sequences together with those from neighboring countries. Six HA lineages belonging to clades 1 and 1.1 were identified since 2004. Lineage 1 shares an ancestor with viruses from Thailand and disappeared after 2005, to be replaced by lineage 2 originating from Vietnam and then by lineage 3. The highly adapted lineage 4 was seen only in Cambodia. Lineage 5 is circulating both in Vietnam and Cambodia since 2008 and was probably introduced in Cambodia through unregistered transboundary poultry trade. Lineage 6 is endemic to Cambodia since 2010 and could be classified as a new clade according to WHO/OIE/FAO criteria for H5N1 virus nomenclature. We propose to name it clade 1.1A. There is a direct filiation of lineages 2 to 6 with a temporal evolution and geographic differentiation for lineages 4 and 6. By the end of 2011, two lineages, i.e. lineages 5 and 6, with different transmission paths cocirculate in Cambodia. The presence of lineage 6 only in Cambodia suggests the existence of a transmission specific to this country whereas the presence of lineage 5 in both Cambodia and Vietnam indicates a distinct way of circulation of infected poultry.
Assuntos
Virus da Influenza A Subtipo H5N1/classificação , Influenza Aviária/epidemiologia , Animais , Camboja/epidemiologia , Linhagem Celular , Embrião de Galinha , Surtos de Doenças , Evolução Molecular , Genes Virais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/genética , Dados de Sequência Molecular , Mutação , Filogenia , Polimorfismo Genético , Aves Domésticas/virologia , Seleção Genética , Homologia de Sequência de AminoácidosRESUMO
BACKGROUND AND AIMS: Tissue engineering strategy has been considered as an alternative treatment for diabetes mellitus due to lack of permanent pharmaceutical treatment and islet donors for transplantation. Various cell lines have been used to generate functional insulin-producing cells (IPCs) including progenitor pancreatic cell lines, embryonic stem cells (ESCs), umbilical cord blood stem cells (UCB-SCs), adult bone marrow stem cells (BMSCs), and adipose tissue-derived stem cells (ADSCs). METHODS: Human ADSCs from lipoaspirated abdominal fat tissue was differentiated into IPCs following a two-step induction protocol based on a combination of alternating high and low glucose, nicotinamide, activin A and glucagon-like peptide 1 (GLP-1) for a duration of 3 weeks. During differentiation, histomorphological changes of the stem cells towards pancreatic ß-islet characteristics were observed via light microscope and transmission electron microscope (TEM). Dithizone (DTZ) staining, which is selective towards IPCs, was used to stain the new islet-like cells. Production of insulin hormone by the cells was analyzed via enzyme-linked immunosorbent assay (ELISA), whereas its hormonal regulation was tested via a glucose challenge test. RESULTS: Histomorphological changes of the differentiated cells were noted to resemble pancreatic ß-cells, whereas DTZ staining positively stained the cells. The differentiated cells significantly produced human insulin as compared to the undifferentiated ADSCs, and its production was increased with an increase of glucose concentration in the culture medium. CONCLUSIONS: These initial data indicate that human lipoaspirated ADSCs have the potential to differentiate into functional IPCs, and could be used as a therapy to treat diabetes mellitus in the future.
Assuntos
Gordura Abdominal/citologia , Células-Tronco Adultas/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Insulina/metabolismo , Células-Tronco Adultas/ultraestrutura , Proteínas Aviárias/farmacologia , Proteínas Aviárias/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Meios de Cultura , Citocinas/farmacologia , Citocinas/fisiologia , Glucose/farmacologia , Glucose/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/ultraestrutura , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/fisiologia , Vesículas Secretórias/ultraestrutura , Engenharia TecidualRESUMO
BACKGROUND: We conducted investigations in 2 villages in Cambodia where outbreaks of influenza H5N1 occurred among humans and poultry to determine the frequency of and risk factors for H5N1 virus transmission. METHODS: During May 2006, approximately 7 weeks after outbreaks of influenza H5N1 among poultry occurred, villagers living near households of 2 patients with influenza H5N1 were interviewed about potential H5N1 exposures and had blood samples obtained for H5N1 serological testing by microneutralization assay. A seropositive result was defined as an influenza H5N1 neutralizing antibody titer of 1:80, with confirmation by Western blot assay. A case-control study was conducted to identify risk factors for influenza H5N1 virus infection. Control subjects, who had seronegative results of tests, were matched with H5N1-seropositive persons by village residence, households with an influenza H5N1-infected poultry flock, sex, and age. RESULTS: Seven (1.0%) of 674 villagers tested seropositive for influenza H5N1 antibodies and did not report severe illness; 6 (85.7%) were male. The 7 H5N1-seropositive persons, all of whom were agedAssuntos
Virus da Influenza A Subtipo H5N1
, Influenza Humana/epidemiologia
, Influenza Humana/virologia
, Adolescente
, Adulto
, Idoso
, Idoso de 80 Anos ou mais
, Animais
, Anticorpos Antivirais/sangue
, Camboja/epidemiologia
, Estudos de Casos e Controles
, Criança
, Pré-Escolar
, Exposição Ambiental
, Humanos
, Lactente
, Pessoa de Meia-Idade
, Aves Domésticas
, Estudos Retrospectivos
, Fatores de Risco
, Estudos Soroepidemiológicos
, Fatores de Tempo
, Adulto Jovem
RESUMO
To understand transmission of avian influenza A (H5N1) virus, we conducted a retrospective survey of poultry deaths and a seroepidemiologic investigation in a Cambodian village where a 28-year-old man was infected with H5N1 virus in March 2005. Poultry surveys were conducted within a 1-km radius of the patient's household. Forty-two household flocks were considered likely to have been infected from January through March 2005 because >60% of the flock died, case-fatality ratio was 100%, and both young and mature birds died within 1 to 2 days. Two sick chickens from a property adjacent to the patient's house tested positive for H5N1 on reverse transcription-PCR. Villagers were asked about poultry exposures in the past year and tested for H5N1 antibodies. Despite frequent, direct contact with poultry suspected of having H5N1 virus infection, none of 351 participants from 93 households had neutralizing antibodies to H5N1. H5N1 virus transmission from poultry to humans remains low in this setting.