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1.
QJM ; 116(3): 205-212, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36222594

RESUMO

BACKGROUND: Genetic predisposition to coronavirus disease 2019 (COVID-19) may contribute to its morbidity and mortality. Because cytokines play an important role in multiple phases of infection, we examined whether commonly occurring, functional polymorphisms in macrophage migration inhibitory factor (MIF) are associated with COVID-19 infection or disease severity. AIM: To determine associations of common functional polymorphisms in MIF with symptomatic COVID-19 or its severity. METHODS: This retrospective case-control study utilized 1171 patients with COVID-19 from three tertiary medical centers in the USA, Hungary and Spain, together with a group of 637 pre-pandemic, healthy control subjects. Functional MIF promoter alleles (-794 CATT5-8,rs5844572), serum MIF and soluble MIF receptor levels, and available clinical characteristics were measured and correlated with COVID-19 diagnosis and hospitalization. Experimental mice genetically engineered to express human high- or low-expression MIF alleles were studied for response to coronavirus infection. RESULTS: In patients with COVID-19, there was a lower frequency of the high-expression MIF CATT7 allele when compared to healthy controls [11% vs. 19%, odds ratio (OR) 0.54 [0.41-0.72], P < 0.0001]. Among inpatients with COVID-19 (n = 805), there was a higher frequency of the MIF CATT7 allele compared to outpatients (n = 187) (12% vs. 5%, OR 2.87 [1.42-5.78], P = 0.002). Inpatients presented with higher serum MIF levels when compared to outpatients or uninfected healthy controls (87 ng/ml vs. 35 ng/ml vs. 29 ng/ml, P < 0.001, respectively). Among inpatients, circulating MIF concentrations correlated with admission ferritin (r = 0.19, P = 0.01) and maximum CRP (r = 0.16, P = 0.03) levels. Mice with a human high-expression MIF allele showed more severe disease than those with a low-expression MIF allele. CONCLUSIONS: In this multinational retrospective study of 1171 subjects with COVID-19, the commonly occurring -794 CATT7MIF allele is associated with reduced susceptibility to symptomatic SARS-CoV-2 infection but increased disease progression as assessed by hospitalization. These findings affirm the importance of the high-expression CATT7MIF allele, which occurs in 19% of the population, in different stages of COVID-19 infection.


Assuntos
COVID-19 , Fatores Inibidores da Migração de Macrófagos , Humanos , Animais , Camundongos , Estudos Retrospectivos , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Fatores Inibidores da Migração de Macrófagos/genética , Teste para COVID-19 , COVID-19/diagnóstico , COVID-19/genética , SARS-CoV-2 , Predisposição Genética para Doença , Oxirredutases Intramoleculares/genética
2.
Trop Anim Health Prod ; 52(6): 3789-3798, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33009586

RESUMO

Leptospirosis is an important economical disease of livestock globally, especially in Asia, the Caribbean, and the African continent. Its presence has been reported in a wide range of livestock. However, information on leptospirosis in South Africa is scanty. We conducted a cross-sectional study in 11 randomly selected abattoirs to determine the seroprevalence and risk factors for leptospirosis in slaughtered cattle in Gauteng province, South Africa. During abattoir visits to selected abattoirs, blood samples were collected from 199 cattle and demographic data obtained on the slaughtered animals. The microscopic agglutination test (MAT) was performed on all sera using a 26-serotype panel using cutoff titer ≥ 1:100. Animal- and abattoir-level risk factors were investigated for their association with seropositivity for leptospirosis. The seroprevalence of leptospirosis in the cattle sampled was 27.6% (55/199). The predominant serogroups detected in seropositive cattle were Sejroe (sv. Hardjo) (38.2%) and Mini sv. Szwajizak) (14.5%) but low to Canicola (sv. Canicola) (1.8%) and Pomona (sv. Pomona) (1.8%). The differences were statistically significant (P < 0.05). Of the five variables investigated, only one (abattoirs) had statistically significantly (P < 0.001) differences in the seroprevalence of leptospirosis among abattoirs. The study documented for the first time in South Africa, the occurrence of serogroups Sejroe (Hardjo bovis strain lely 607), Tarassovi, Hebdomadis, and Medanensis in slaughtered cattle. It was concluded that six of the nine serovars (representing seven serogroups) of Leptospira spp. circulating in cattle population in South Africa are not vaccine serogroups. The clinical, diagnostic, and public health importance of the findings cannot be ignored.


Assuntos
Doenças dos Bovinos/epidemiologia , Leptospirose/veterinária , Matadouros , Testes de Aglutinação/veterinária , Animais , Bovinos , Estudos Transversais , Leptospira/imunologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , Fatores de Risco , Estudos Soroepidemiológicos , Sorogrupo , África do Sul/epidemiologia
3.
Clin Microbiol Infect ; 24(6): 646-652, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29133154

RESUMO

OBJECTIVES: We aimed to report the first 54 cases of pregnant women infected by Zika virus (ZIKV) and their virologic and clinical outcomes, as well as their newborns' outcomes, in 2016, after the emergence of ZIKV in dengue-endemic areas of São Paulo, Brazil. METHODS: This descriptive study was performed from February to October 2016 on 54 quantitative real-time PCR ZIKV-positive pregnant women identified by the public health authority of São José do Rio Preto, São Paulo, Brazil. The women were followed and had clinical and epidemiologic data collected before and after birth. Adverse outcomes in newborns were analysed and reported. Urine or blood samples from newborns were collected to identify ZIKV infection by reverse transcription PCR (RT-PCR). RESULTS: A total of 216 acute Zika-suspected pregnant women were identified, and 54 had the diagnosis confirmed by RT-PCR. None of the 54 women miscarried. Among the 54 newborns, 15 exhibited adverse outcomes at birth. The highest number of ZIKV infections occurred during the second and third trimesters. No cases of microcephaly were reported, though a broad clinical spectrum of outcomes, including lenticulostriate vasculopathy, subependymal cysts, and auditory and ophthalmologic disorders, were identified. ZIKV RNA was detected in 18 of 51 newborns tested and in eight of 15 newborns with adverse outcomes. CONCLUSIONS: Although other studies have associated many newborn outcomes to ZIKV infection during pregnancy, these same adverse outcomes were rare or nonexistent in this study. The clinical presentation the newborns we studied was mild compared to other reports, suggesting that there is significant heterogeneity in congenital Zika infection.


Assuntos
Doenças Fetais/virologia , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/complicações , Zika virus/isolamento & purificação , Adulto , Brasil , Feminino , Humanos , Recém-Nascido , Filogenia , Gravidez , Adulto Jovem , Zika virus/classificação , Zika virus/genética
4.
Epidemiol Infect ; 145(16): 3438-3448, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29173242

RESUMO

Infectious diseases frequently have multiple potential routes of intraspecific transmission of pathogens within wildlife and other populations. For pathogens causing zoonotic diseases, knowing whether these transmission routes occur in the wild and their relative importance, is critical for understanding maintenance, improving control measures and ultimately preventing human disease. The Norway rat (Rattus norvegicus) is the primary reservoir of leptospirosis in the urban slums of Salvador, Brazil. There is biological evidence for potentially three different transmission routes of leptospire infection occurring in the rodent population. Using newly obtained prevalence data from rodents trapped at an urban slum field site, we present changes in cumulative risk of infection in relation to age-dependent transmission routes to infer which intra-specific transmission routes occur in the wild. We found that a significant proportion of animals leave the nest with infection and that the risk of infection increases throughout the lifetime of Norway rats. We did not observe a significant effect of sexual maturity on the risk of infection. In conclusion, our results suggest that vertical and environmental transmission of leptospirosis both occur in wild populations of Norway rats.


Assuntos
Leptospira , Leptospirose , Doenças dos Roedores , Envelhecimento , Animais , Peso Corporal , Brasil/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/transmissão , Portador Sadio/veterinária , Feminino , Transmissão Vertical de Doenças Infecciosas , Leptospirose/epidemiologia , Leptospirose/transmissão , Leptospirose/veterinária , Masculino , Prevalência , Ratos , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/transmissão , Análise de Sobrevida
5.
Epidemiol Infect ; 145(2): 334-338, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780498

RESUMO

Urban slum environments in the tropics are conducive to the proliferation and the spread of rodent-borne zoonotic pathogens to humans. Calodium hepaticum (Brancroft, 1893) is a zoonotic nematode known to infect a variety of mammalian hosts, including humans. Norway rats (Rattus norvegicus) are considered the most important mammalian host of C. hepaticum and are therefore a potentially useful species to inform estimates of the risk to humans living in urban slum environments. There is a lack of studies systematically evaluating the role of demographic and environmental factors that influence both carriage and intensity of infection of C. hepaticum in rodents from urban slum areas within tropical regions. Carriage and the intensity of infection of C. hepaticum were studied in 402 Norway rats over a 2-year period in an urban slum in Salvador, Brazil. Overall, prevalence in Norway rats was 83% (337/402). Independent risk factors for C. hepaticum carriage in R. norvegicus were age and valley of capture. Of those infected the proportion with gross liver involvement (i.e. >75% of the liver affected, a proxy for a high level intensity of infection), was low (8%, 26/337). Sixty soil samples were collected from ten locations to estimate levels of environmental contamination and provide information on the potential risk to humans of contracting C. hepaticum from the environment. Sixty percent (6/10) of the sites were contaminated with C. hepaticum. High carriage levels of C. hepaticum within Norway rats and sub-standard living conditions within slum areas may increase the risk to humans of exposure to the infective eggs of C. hepaticum. This study supports the need for further studies to assess whether humans are becoming infected within this community and whether C. hepaticum is posing a significant risk to human health.


Assuntos
Capillaria/isolamento & purificação , Portador Sadio/veterinária , Infecções por Enoplida/veterinária , Carga Parasitária , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/parasitologia , Animais , Brasil/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/parasitologia , Infecções por Enoplida/epidemiologia , Infecções por Enoplida/parasitologia , Infecções por Enoplida/patologia , Áreas de Pobreza , Prevalência , Ratos , Fatores de Risco , Doenças dos Roedores/patologia
6.
Epidemiol Infect ; 144(11): 2420-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27019024

RESUMO

Leptospirosis is a zoonosis caused by bacteria of the genus Leptospira. The disease is globally distributed and a major public health concern. The Norway rat (Rattus norvegicus) is the main reservoir of the pathogen in urban slums of developing and developed countries. The potential routes of intra-specific leptospire transmission in rats are largely unknown. Herein, we identified pathogenic Leptospira spp. in breast tissue and milk of naturally infected rats. We examined kidney, breast tissue and milk from 24 lactating rats for the presence of leptospires using immunofluorescence, immunohistochemistry, polymerase chain reaction (PCR) and scanning electronic microscopy. All 24 rats had evidence for Leptospira in the kidneys, indicating chronic carriage. The majority of kidney-positive rats had detectable leptospires in milk (18, 75%) and breast tissue (16, 67%), as evidenced by immunofluorescence assay and immunohistochemistry. Four (17%) milk samples and two (8%) breast tissue samples were positive by quantitative real-time PCR. Scanning electron microscopy confirmed the presence of leptospires in breast tissue. No major pathological changes in breast tissue were found. This study, for the first time, identified leptospires in the milk and breast tissue of wild Norway rats, suggesting the possibility of milk-borne transmission of leptospirosis to neonates.


Assuntos
Transmissão Vertical de Doenças Infecciosas/veterinária , Leptospira/isolamento & purificação , Leptospirose/veterinária , Glândulas Mamárias Animais/microbiologia , Leite/microbiologia , Doenças dos Roedores/epidemiologia , Animais , Brasil/epidemiologia , Feminino , Imunofluorescência/veterinária , Imuno-Histoquímica/veterinária , Leptospira/classificação , Leptospirose/epidemiologia , Leptospirose/microbiologia , Microscopia Eletrônica de Varredura/veterinária , Ratos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Roedores/microbiologia
7.
Acta Trop ; 107(3): 255-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18671932

RESUMO

There is scarce data on the burden of leptospirosis and its epidemiological characteristics in Argentina. This study aimed to evaluate distribution of leptospirosis cases and identify risk factors for the disease during national laboratory-based surveillance. From January 1999 to December 2005, 812 suspected cases were referred to the national reference laboratory, of which 182 and 463 had respectively, laboratory confirmed and unconfirmed diagnosis of leptospirosis. The diagnosis of leptospirosis was discarded in 167 cases. The most prevalent presumptive infecting serogroup was Icterohaemorrhagie followed by Pomona, Ballum and Canicola. The majority of cases occurred during the worm and rainy months. Confirmed cases were predominantly adults and males, who presented with fever, headache and myalgias. Severe clinical manifestations included jaundice and acute renal insufficiency. Conjunctival suffusion, a hallmark clinical sign of leptospirosis, was found in 55% of confirmed cases, and 43% of the cases with discarded diagnosis (p=0.036). After multivariate analyses, age >30 years (OR=2.16; 1.05-4.41), occupation in a rural setting (OR=3.41; 1.45-8.06), contact with contaminated surface water (OR=2.17; 1.01-4.68), and contact with floods (OR=4.49; 1.17-17.25) were significantly associated with leptospirosis. In conclusion, although activities associated with rural occupations remain important risk factors in Argentina, exposures occurring during flooding events have emerged to be the major risk factor for leptospirosis.


Assuntos
Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Leptospirose/fisiopatologia , Adulto , Fatores Etários , Argentina/epidemiologia , Feminino , Humanos , Incidência , Leptospira/classificação , Leptospirose/complicações , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estações do Ano , Fatores Sexuais
8.
J Comp Pathol ; 137(4): 231-238, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17996544

RESUMO

Leptospirosis is a widespread anthropozoonosis, with a broad array of mammalian reservoirs, occurring as rural endemics, urban outbreaks related to floods, and emergent disease associated with water sports and recreational exposure in developed countries. Rats are the major source of human infection, particularly in urban areas; however few reports have focused on the pathology of leptospirosis in this host. This study reports pathological changes in 60 kidneys from captured wild rats and compares these with changes in the kidney of Wistar rats experimentally infected with Leptospira interrogans serovar Copenhageni strain FIOCRUZ L1-130. A broad range of morphological alterations were detected in the kidneys from captured rats but interstitial nephritis was the only feature reproduced under experimental conditions. The role of interstitial nephritis in the pathogenesis of leptospirosis is reviewed and it is suggested that rats may provide a potential tool for the study of colonization mechanisms and host resistance in acute leptospiral disease.


Assuntos
Rim/patologia , Leptospira interrogans , Leptospirose/patologia , Leptospirose/veterinária , Doenças dos Roedores/patologia , Animais , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Nefrite Intersticial/microbiologia , Nefrite Intersticial/patologia , Ratos , Ratos Wistar
9.
J Immunoassay Immunochem ; 28(3): 279-88, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17613673

RESUMO

LipL32 is the major lipoprotein in the membrane of pathogenic leptospira. In this work, we report on the production of monoclonal antibodies (MAbs) against recombinant LipL32 (rLipL32) and on the evaluation of their potential for use as reagents in diagnostic tests for leptospirosis. The MAbs were all of the IgG(2b) isotype and reacted specifically with native LipL32 in pathogenic serovars only. MAbs reacted in the same region of the rLipL32 molecule and their affinity constant was between 5x10(7) M(-1) and 6x10(6) M(-1). These results suggest that although the MAbs cannot be used together, they are well suited for diagnostic tests of leptospirosis based on LipL32 detection.


Assuntos
Anticorpos Monoclonais/química , Proteínas da Membrana Bacteriana Externa/imunologia , Leptospirose/diagnóstico , Lipoproteínas/imunologia , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/isolamento & purificação , Especificidade de Anticorpos/imunologia , Proteínas da Membrana Bacteriana Externa/análise , Testes Diagnósticos de Rotina , Humanos , Isotipos de Imunoglobulinas/análise , Testes Imunológicos , Leptospirose/imunologia , Lipoproteínas/análise
10.
Klin Lab Diagn ; (2): 3-6, 2006 Feb.
Artigo em Russo | MEDLINE | ID: mdl-16610621

RESUMO

The investigation quantitatively determined the content of low-molecular-weight aromatic compounds of microbial origin in the sera of 34 individuals by chromatographic mass spectrometry. An "Agilent Technogies 6890N" gas chromatograph with a 5973 mass selective detector was applied; chromatographic separation of components was effected on an Hp-5MS quartz capillary column. Aromatic small molecules originating from microbes (SMOM) were determined in the sera of 7 patients with sepsis. The diagnosis of sepsis was documented by the presence of the systemic inflammation syndrome and by that of bacteriemia and/or artificial ventilation-associated pneumonia along with the level of procalcitonin of higher than 10 ng/ml. The levels of aromatic SMOM were compared in 10 healthy donors, 8 preoperative cardiosurgical patients, and 9 patients with different abnormalities without sepsis treated in an intensive care unit (ICU). Serum phenylacetic and 3-phenylpropionic acids were found to be prevalent in the healthy donors and postoperative cardiosurgical patients. In ICU patients with different complications without sepsis, more than half the compounds under study were undetectable, the others were found in very low concentrations, which may be accounted for by antibiotic therapy. At the same time, almost the whole spectrum of the test compounds (other than 3-phenylpropionic acid) with the highest concentrations of 3-phenyllactic, p-hydroxyphenylacetic, 3-(p-hydroxyphenyl)lactic and 2-hydroxybutanic acids, was detectable in septic patients receiving a more intensive therapy. The differences were statistically significant (by the Mann-Whitney U-test; p < 0.05). By taking into account the potentially high biological activity of the test compounds, studies are to be continued in this area.


Assuntos
Bactérias/química , Fenilacetatos/sangue , Fenilpropionatos/sangue , Sepse/sangue , Cromatografia Líquida/métodos , Feminino , Humanos , Masculino , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Fenilacetatos/química , Fenilpropionatos/química , Valor Preditivo dos Testes , Sepse/microbiologia
12.
J Bacteriol ; 186(7): 2164-72, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15028702

RESUMO

Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in accidental hosts, including humans. Complete genome sequencing of Leptospira interrogans serovar Copenhageni and comparative analysis with the available Leptospira interrogans serovar Lai genome reveal that despite overall genetic similarity there are significant structural differences, including a large chromosomal inversion and extensive variation in the number and distribution of insertion sequence elements. Genome sequence analysis elucidates many of the novel aspects of leptospiral physiology relating to energy metabolism, oxygen tolerance, two-component signal transduction systems, and mechanisms of pathogenesis. A broad array of transcriptional regulation proteins and two new families of afimbrial adhesins which contribute to host tissue colonization in the early steps of infection were identified. Differences in genes involved in the biosynthesis of lipopolysaccharide O side chains between the Copenhageni and Lai serovars were identified, offering an important starting point for the elucidation of the organism's complex polysaccharide surface antigens. Differences in adhesins and in lipopolysaccharide might be associated with the adaptation of serovars Copenhageni and Lai to different animal hosts. Hundreds of genes encoding surface-exposed lipoproteins and transmembrane outer membrane proteins were identified as candidates for development of vaccines for the prevention of leptospirosis.


Assuntos
Genoma Bacteriano , Genômica , Leptospira interrogans/fisiologia , Leptospira interrogans/patogenicidade , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cricetinae , Humanos , Leptospira interrogans/classificação , Leptospira interrogans/genética , Leptospirose/microbiologia , Camundongos , Dados de Sequência Molecular , Análise de Sequência de DNA , Sorotipagem , Virulência/genética
13.
Antibiot Khimioter ; 48(7): 12-5, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14628572

RESUMO

In vitro activity of cefepime against etiologically significant strains of gramnegative microflora of patients treated in the Reanimation and Intensive Care Unit after cardiosurgical operations was evaluated. Sixty four strains of gramnegative aerobic bacteria isolated within the period from October 2001 to April 2002 were tested. The isolates susceptibility was determined by the disk diffusion method. Cefepime had an obvious advantage over the 3rd generation cephalosporins. Low incidence of cefepime resistant strains of the problem organisms in the Reanimation and Intensive Care Unit should be taken into account in empirical therapy of infections due to such pathogens.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Bactérias Aeróbias Gram-Negativas/efeitos dos fármacos , Serviço Hospitalar de Cardiologia , Cefepima , Bactérias Aeróbias Gram-Negativas/isolamento & purificação , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Centro Cirúrgico Hospitalar
14.
Am J Trop Med Hyg ; 65(5): 657-63, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11716133

RESUMO

During heavy seasonal rainfall in 1996, concurrent epidemics of dengue and leptospirosis occurred in an urban center in northeastern Brazil. We interviewed 110 cases of leptospirosis hospitalized a median of seven days after the onset of illness to evaluate the impact of the dengue epidemic on the triage of suspected leptospirosis from ambulatory clinics to the infectious disease reference hospital. Within the first three days of illness, 46 (42%) cases sought their first medical evaluation, and 28 (61% of 46) received a diagnosis of dengue. Dengue diagnoses were associated with a median of five days delay in referral to the infectious disease hospital. Patients who reported initial diagnoses of dengue were more likely than other patients to have required admission to the intensive care unit (odds ratio [OR] = 2.7, 95% confidence interval [CI] = 0.8-9.5) and to have died during hospitalization (OR = 5.1, 95% CI = 0.8-55.0). These findings indicate that diagnostic confusion between the early symptoms of leptospirosis and dengue may have contributed to the high mortality observed during the leptospirosis epidemic.


Assuntos
Dengue/diagnóstico , Leptospirose/diagnóstico , Encaminhamento e Consulta , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Arch Neurol ; 58(9): 1395-402, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559310

RESUMO

OBJECTIVES: To determine whether nondemented subjects with pathological evidence of preclinical Alzheimer disease (AD) demonstrate neuronal loss in the entorhinal cortex and hippocampus, and whether the onset of cognitive deficits in AD coincides with the onset of neuronal degeneration. METHODS: Preclinical AD cases have been defined by the absence of cognitive decline but with neuropathological evidence of AD. The hippocampus and entorhinal cortex were examined in 13 nondemented cases (Clinical Dementia Rating [CDR] 0) with healthy brains, 4 cases with preclinical AD, 8 cases with very mild symptomatic AD (CDR 0.5), and 4 cases with severe AD (CDR 3, hippocampus only). The volume and number of neurons were determined stereologically in 2 areas that are vulnerable to AD--the entorhinal cortex (as a whole and layer II alone) and hippocampal field CA1. RESULTS: There was no significant decrease in neuron number or volume with age in the healthy nondemented group and little or none between the healthy and preclinical AD groups. Substantial decreases were found in the very mild AD group in neuron number (35% in the entorhinal cortex, 50% in layer II, and 46% in CA1) and volume (28% in the entorhinal cortex, 21% in layer II, and 29% in CA1). Greater decrements were observed in CA1 in the severe AD group. CONCLUSIONS: There is little or no neuronal loss in aging or preclinical AD but substantial loss in very mild AD. The findings indicate that AD results in clinical deficits only when it produces significant neuronal loss.


Assuntos
Doença de Alzheimer/patologia , Córtex Entorrinal/patologia , Hipocampo/patologia , Neurônios/patologia , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Transtornos Cognitivos/patologia , Humanos , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia
16.
J Clin Microbiol ; 39(9): 3303-10, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11526167

RESUMO

There is an urgent need for development of new serodiagnostic strategies for leptospirosis, an emerging zoonosis with worldwide distribution. We have evaluated the diagnostic utility of five recombinant antigens in enzyme-linked immunosorbent assays (ELISAs) for serodiagnosis of leptospirosis. Sera from 50 healthy residents of a high-incidence region were used to determine cutoff values for 96% specificity. In paired sera from 50 cases of leptospirosis confirmed by the microscopic agglutination test, immunoglobulin G (IgG) but not IgM reacted with the recombinant leptospiral proteins. The recombinant LipL32 IgG ELISA had the highest sensitivities in the acute (56%) and convalescent (94%) phases of leptospirosis. ELISAs based on recombinant OmpL1, LipL41, and Hsp58 had sensitivities of 16, 24, and 18% during the acute phase and 72, 44, and 32% during convalescence, respectively. Compared to sera from healthy individuals, patient sera did not react significantly with recombinant LipL36 (P > 0.05). Recombinant LipL32 IgG ELISA demonstrated 95% specificity among 100 healthy individuals, and specificities ranging from 90 to 97% among 30 dengue patients, 30 hepatitis patients, and 16 patients with diseases initially thought to be leptospirosis. Among 39 Venereal Disease Research Laboratory test-positive individuals and 30 Lyme disease patients, 13 and 23% of sera, respectively, reacted positively with the rLipL32 antigen. These findings indicate that rLipL32 may be an useful antigen for the serodiagnosis of leptospirosis.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Leptospira/imunologia , Leptospirose/diagnóstico , Antígenos de Bactérias/genética , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Imunoglobulina G/sangue , Lipoproteínas/genética , Lipoproteínas/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
17.
Infect Immun ; 69(8): 4958-68, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11447174

RESUMO

Leptospirosis is an emerging zoonosis caused by pathogenic spirochetes belonging to the genus Leptospira. An understanding of leptospiral protein expression regulation is needed to develop new immunoprotective and serodiagnostic strategies. We used the humoral immune response during human leptospirosis as a reporter of protein antigens expressed during infection. Qualitative and quantitative immunoblot analysis was performed using sera from 105 patients from Brazil and Barbados. Sera from patients with other diseases and healthy individuals were evaluated as controls. Seven proteins, p76, p62, p48, p45, p41, p37, and p32, were identified as targets of the humoral response during natural infection. In both acute and convalescent phases of illness, antibodies to lipopolysaccharide were predominantly immunoglobulin M (IgM) while antibodies to proteins were exclusively IgG. Anti-p32 reactivity had the greatest sensitivity and specificity: positive reactions were observed in 37 and 84% of acute- and convalescent-phase sera, respectively, while only 5% of community control individuals demonstrated positive reactions. Six immunodominant antigens were expressed by all pathogenic leptospiral strains tested; only p37 was inconsistently expressed. Two-dimensional immunoblots identified four of the seven infection-associated antigens as being previously characterized proteins: LipL32 (the major outer membrane lipoprotein), LipL41 (a surface-exposed outer membrane lipoprotein), and heat shock proteins GroEL and DnaK. Fractionation studies demonstrated LipL32 and LipL41 reactivity in the outer membrane fraction and GroEL and DnaK in the cytoplasmic fraction, while p37 appeared to be a soluble periplasmic protein. Most of the other immunodominant proteins, including p48 and p45, were localized to the inner membrane. These findings indicate that leptospiral proteins recognized during natural infection are potentially useful for serodiagnosis and may serve as targets for vaccine design.


Assuntos
Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Leptospirose/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias , Fracionamento Celular , Eletroforese em Gel Bidimensional/métodos , Humanos , Leptospira/imunologia , Leptospirose/sangue , Coelhos
18.
J Clin Microbiol ; 39(1): 191-5, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11136769

RESUMO

A new repetitive DNA element was identified in an isolate of Leptospira interrogans serovar copenhageni from a patient in Salvador, Brazil. A Sau3A genomic library from this strain was constructed and screened for repetitive DNA elements. An insert of 438 bp (Rep1) from one library clone hybridized to multiple chromosomal DNA fragments resolved electrophoretically after digestion with BamHI, HindIII, and MfeI. A single oligonucleotide primer, designated iRepl, was designed to generate multiple PCR amplicons of various electrophoretic mobilities in a PCR typing method. The method distinguished strains belonging to the eight pathogenic and three saprophytic species of the genus Leptospira. Clinical isolates obtained during urban epidemics between 1996 and 1998 in Salvador, Brazil, were analyzed by this PCR method. Although the iRep1 primer was unable to discriminate strains among L. interrogans serovar copenhageni isolates, it was able to differentiate strains belonging to different species and serogroups of Leptospira identified in Salvador. This PCR-based method may provide a faster and less expensive alternative to serologic tests used in reference laboratories.


Assuntos
Leptospira interrogans/classificação , Leptospira interrogans/genética , Leptospira/classificação , Repetições de Trinucleotídeos/genética , Doença de Weil/microbiologia , Animais , Sequência de Bases , DNA Bacteriano/análise , DNA Bacteriano/genética , Dosagem de Genes , Biblioteca Genômica , Humanos , Leptospira/genética , Leptospira interrogans/isolamento & purificação , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Sorotipagem , Doença de Weil/epidemiologia
19.
Clin Infect Dis ; 30(1): 78-86, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10619737

RESUMO

Active hospital-based surveillance in the city of Salvador, Brazil, from December 1995 through October 1998, identified 221 patients with confirmed pneumococcal meningitis. Of these 221 patients, 29 (13%) had isolates with intermediate-level resistance to penicillin. Infection with these penicillin-nonsusceptible isolates was significantly associated with age of <2 years (P<.0019), previous antibiotic use (P<.0006), and coresistance to trimethoprim-sulfamethoxazole (P<.0000). Serotype 14 was the most prevalent serotype (55.2%) of penicillin-nonsusceptible isolates. Strain typing by repetitive element BOX polymerase chain reaction (PCR) analysis showed that penicillin-nonsusceptible serotype 14 isolates had closely related BOX PCR patterns, whereas penicillin-susceptible serotype 14 isolates each had distinct, unrelated patterns. Penicillin-nonsusceptible serotype 14 isolates from Salvador and other Brazilian cities had similar BOX PCR patterns. These observations indicate that in Brazil a large proportion of cases of penicillin-nonsusceptible pneumococcal meningitis appear to be caused by a closely related group of serotype 14 strains that may have disseminated to widely separate geographic areas.


Assuntos
Meningite Pneumocócica/epidemiologia , Meningite Pneumocócica/microbiologia , Resistência às Penicilinas , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Adulto , Antibacterianos/farmacologia , Brasil/epidemiologia , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase/métodos , Vigilância da População , Fatores de Risco , Sorotipagem , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
20.
J Infect Dis ; 180(5): 1735-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10515844

RESUMO

The response to recombinant human granulocyte macrophage colony-stimulating factor (GM-CSF) in the treatment of cutaneous leishmaniasis was evaluated. Twenty patients with cutaneous leishmaniasis who had lesions for 60 days were enrolled in a double-blind placebo trial of GM-CSF with standard parenteral sodium stibogluconate (20 mg/kg-1/day-1) for 20 days. Ten patients were randomized to receive intralesionally injected GM-CSF (200 microgram) at enrollment and 1 week after, and 10 patients received saline as placebo. GM-CSF- and antimony-treated patients healed faster than patients who received antimony alone (49+/-32.8 vs. 110+/-61.6 days, P<.05). Seven of 10 patients were healed of their lesions before 40 days after therapy in the GM-CSF group, compared with only 1 of 10 patients in the placebo group (relative risk, 7; 95% confidence interval, 1.04-47.00). Thus, GM-CSF plus antimony significantly increased the chance of lesion healing in 40 days.


Assuntos
Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Adolescente , Adulto , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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