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1.
BMC Public Health ; 24(1): 453, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38350875

RESUMEN

BACKGROUND: Multimorbidity, the concurrent presence of two or more chronic conditions is an emerging public health challenge. Till date, most of the research have focused on the presence and interaction of selected co-morbidities in tuberculosis (TB). There exist a critical knowledge gap on the magnitude of multimorbidity among TB patients and its impact on health outcomes. METHODS: We undertook a cross-sectional study to assess the prevalence and patterns of multimorbidity among newly diagnosed TB patients in two states of India. A total of 323 patients were interviewed using a structured multimorbidity assessment questionnaire for primary care (MAQ-PC). MAQ-PC is already validated for Indian population and elicits 22 chronic conditions. We defined TB multimorbidity as the co-existence of TB with one or more chronic conditions and identified commonly occurring dyads (TB + single condition) and triads (TB + two conditions). RESULTS: More than half (52%) of TB patients reported multimorbidity. Among dyads, depression, diabetes mellitus (DM), acid peptic disease (APD), hypertension, chronic alcoholism, arthritis and chronic back ache (CBA) were the most common co-occurring conditions while 'DM + arthritis', 'depression + APD', 'depression + DM' were the most commonly occurring triads among TB patients. Factors such as increasing age, low levels of education, alcohol abusers, drug-resistant TB and having health insurance were significantly associated with multimorbidity among TB patients. CONCLUSIONS: Our findings suggest high prevalence of multimorbidity among newly diagnosed TB patients in India. The presence of concordant and discordant conditions with TB may increase the health complexity, thus necessitating appropriate care protocols. Given, the current situation, wherein TB and non-communicable diseases (NCD) services are delivered through collaborative framework between programmes, there is a need for addressing multimorbidity at the healthcare delivery level.


Asunto(s)
Artritis , Diabetes Mellitus , Tuberculosis , Humanos , Multimorbilidad , Estudios Transversales , Tuberculosis/epidemiología , Enfermedad Crónica , Prevalencia , India/epidemiología
2.
Braz J Med Biol Res ; 50(5): e5590, 2017 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-28443987

RESUMEN

Meningococcus serogroup B (MenB), clonal complex 32 (cc 32), was the Brazilian epidemic strain of meningococcal disease (MD) in the 1990's. Currently, meningococcus serogroup C (MenC), cc 103, is responsible for most of the cases of the disease in Brazil. The aim of this study was to investigate the seroprevalence of bactericidal antibody (SBA) against representative epidemic strains of MenC, (N753/00 strain, C:23:P1.22,14-6, cc103) and MenB, (Cu385/83 strain, B:4,7:P1.15,19, cc32) in students and employees of a university hospital in the State of Rio Grande do Sul (RS, Brazil). A second MenC strain (N79/96, C:2b:P1.5-2,10, cc 8) was used as a prototype strain of Rio de Janeiro's outbreak that occurred in the 1990's. Our previous study showed a 9% rate of asymptomatic carriers in these same individuals. A second goal was to compare the SBA prevalence in meningococcal carriers and non-carriers. Fifty-nine percent of the studied population showed protective levels of SBA titers (log2≥2) against at least one of the three strains. About 40% of the individuals had protective levels of SBA against N753/00 and Cu385/83 strains. Nonetheless, only 22% of the individuals showed protective levels against N79/96 strain. Significantly higher antibody levels were seen in carriers compared to non-carriers (P≤0.009). This study showed that, similar to other States in Brazil, a MenC (23:P1.22,14-6, cc103) strain with epidemic potential is circulating in this hospital. Close control by the Epidemiological Surveillance Agency of RS of the number of cases of MD caused by MenC strains in the State is recommended to prevent a new disease outbreak.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Neisseria meningitidis Serogrupo B/inmunología , Neisseria meningitidis Serogrupo C/inmunología , Adulto , Brasil , Femenino , Hospitales Universitarios , Humanos , Immunoblotting/métodos , Masculino , Infecciones Meningocócicas/inmunología , Persona de Mediana Edad , Neisseria meningitidis Serogrupo B/aislamiento & purificación , Neisseria meningitidis Serogrupo C/aislamiento & purificación , Estudios Seroepidemiológicos , Serogrupo , Determinación de Anticuerpos Séricos Bactericidas , Estadísticas no Paramétricas , Adulto Joven
3.
Epidemiol Infect ; 140(5): 906-15, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21875453

RESUMEN

SUMMARYAn outbreak of meningococcal disease (MD) with severe morbidity and mortality was investigated in midwestern Brazil in order to identify control measures. A MD case was defined as isolation of Neisseria meningitidis, or detection of polysaccharide antigen in a sterile site, or presence of clinical purpura fulminans, or an epidemiological link with a laboratory-confirmed case-patient, between June and August 2008. In 8 out of 16 MD cases studied, serogroup C ST103 complex was identified. Five (31%) cases had neurological findings and five (31%) died. The attack rate was 12 cases/100 000 town residents and 60 cases/100 000 employees in a large local food-processing plant. We conducted a matched case-control study of eight primary laboratory-confirmed cases (1:4). Factors associated with illness in single variable analysis were work at the processing plant [matched odds ratio (mOR) 22, 95% confidence interval (CI) 2·3-207·7, P<0·01], and residing <1 year in Rio Verde (mOR 7, 95% CI 1·11-43·9, P<0·02). Mass vaccination (>10 000 plant employees) stopped propagation in the plant, but not in the larger community.


Asunto(s)
Brotes de Enfermedades , Control de Infecciones/métodos , Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo C/aislamiento & purificación , Exposición Profesional , Adolescente , Adulto , Brasil/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/mortalidad , Infecciones Comunitarias Adquiridas/prevención & control , Femenino , Manipulación de Alimentos , Humanos , Lactante , Masculino , Vacunación Masiva/métodos , Infecciones Meningocócicas/mortalidad , Infecciones Meningocócicas/prevención & control , Persona de Mediana Edad , Vacunas Neumococicas/administración & dosificación , Análisis de Supervivencia , Adulto Joven
4.
J Infect ; 59(2): 104-14, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19576638

RESUMEN

OBJECTIVES: To improve the understanding of serogroup Y invasive meningococcal disease (IMD) in Latin America, particularly IMD molecular epidemiology; 166 Y serogroup isolates received at the National Reference Laboratories of Argentina, Brazil, Chile, Colombia, and Costa Rica during 2000-2006 were characterized by their molecular markers. METHODS: This analysis included serological assays to determine serogroup/serotype/serosubtype, DNA sequencing and genotyping of the porB and/or porA genes, multilocus sequence typing (MLST) and fetA allele determination. RESULTS: Sixteen different antigenic combinations were observed. Sixty-two (37.3%) isolates were NT:P1.5 and 36 (21.7%) isolates were 14:NST. Thirty-two different STs appeared, but 3 STs (ST-1624, ST-23, and ST-5770) accounted for 69.9% (116) of the strains. Most of the IMD isolates belonged to the ST-23, ST-167 clonal complexes or the group composed by ST-5770 and related STs. CONCLUSIONS: Isolates obtained in Colombia and Costa Rica were similar to that of the United States, in that most sequence types belonged to the ST-23 clonal complex. IMD isolates found in Argentina appear to be the result of an independent event and did not spread from nearby countries, being the sequence type ST-1624 (ST-167 clonal complex) the most frequently found. We were unable to correlate an antigenic shift of outer membrane proteins with an increase of serogroup Y meningococcal cases in our collection of isolates.


Asunto(s)
Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo Y/clasificación , Neisseria meningitidis Serogrupo Y/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de la Membrana Bacteriana Externa/genética , Técnicas de Tipificación Bacteriana , Niño , Preescolar , Dermatoglifia del ADN , Femenino , Genotipo , Humanos , Lactante , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Neisseria meningitidis Serogrupo Y/genética , Porinas/genética , Análisis de Secuencia de ADN , Serotipificación , Adulto Joven
5.
Mol Genet Genomics ; 271(5): 511-21, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15069639

RESUMEN

Glutathione S-transferases (GSTs) comprise a large family of key defence enzymes against xenobiotic toxicity. Here we describe the comprehensive characterisation of this important multigene family in the model monocot species rice [ Oryza sativa(L.)]. Furthermore, we investigate the molecular evolution of the family based on the analysis of (1) the patterns of within-genome duplication, and (2) the phylogenetic relationships and evolutionary divergence among rice, Arabidopsis, maize and soybean GSTs. By in-silico screening of the EST and genome divisions of the Genbank/EMBL/DDBJ database we have isolated 59 putative genes and two pseudogenes, making this the largest plant GST family characterised to date. Of these, 38 (62%) are represented by genomic and EST sequences and 23 (38%) are known only from their genomic sequences. A preliminary survey of EST collections shows a large degree of variability in gene expression between different tissues and environmental conditions, with a small number of genes (13) accounting for 80% of all ESTs. Rice GSTs are organised in four main phylogenetic classes, with 91% of all rice genes belonging to the two plant-specific classes Tau (40 genes) and Phi (16 genes). Pairwise identity scores range between 17 and 98% for proteins of the same class, and 7 and 21% for interclass comparisons. Rapid evolution by gene duplication is suggested by the discovery of two large clusters of 7 and 23 closely related genes on chromosomes 1 and 10, respectively. A comparison of the complete GST families in two monocot and two dicot species suggests a monophyletic origin for all Theta and Zeta GSTs, and no more than three common ancestors for all Phi and Tau genes.


Asunto(s)
Glutatión Transferasa/genética , Oryza/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Evolución Molecular , Etiquetas de Secuencia Expresada , Duplicación de Gen , Expresión Génica , Genes de Plantas , Familia de Multigenes , Filogenia , Glycine max/genética , Zea mays/genética
6.
Int. j. med. microbiol ; 52(2): 121-125, Feb.2003.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1063571

RESUMEN

A mAb against the NadA protein from Neisseria meningitidis strain 3006 (serosubtype B : 2b : P1.2 : P5.2,8) demonstrated strong bactericidal activity against Brazilian epidemic serogroup B strain N44/89 (B : 4,7 : P1.19,15 : P5.5,7) and a serogroup C strain, IMC 2135 (C : 2a : P1.5,2), but not against another serogroup C strain, N1002/90 (C : 2b : P1.3 : P5.8). The immunogenicity of native NadA in an outer-membrane vesicle (OMV) preparation was also tested. Serum from mice immunized with OMV from serogroup B strain N44/89, which contains the NadA protein, showed bactericidal activity against serogroup B and C strains possessing NadA. In dot-blot analysis of 100 serogroup B and 100 serogroup C isolates from Brazilian patients, the mAb to NadA recognized about 60% of the samples from both serogroups. The molecular mass of the NadA protein from strain N44/89 determined by mass spectrometry was 37 971 Da and the peptide sequences were identical to those of NadA from N. meningitidis strain MC58.


Asunto(s)
Ratones , Neisseria meningitidis Serogrupo B/inmunología , Neisseria meningitidis Serogrupo C/inmunología , Vacunas Meningococicas/inmunología , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/química , Brasil
7.
J Biomech Eng ; 122(5): 498-503, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11091951

RESUMEN

Nonlinear thin film rupture has been analyzed by investigating the stability of tear films to finite amplitude disturbances. The dynamics of the liquid film is formulated using the Navier-Stokes equations, including a body force term due to van der Waals attractions. The governing equation was solved by the finite difference method as part of an initial value problem for spatial periodic boundary conditions. The rupture of the tear film covering the cornea and the formation of dry spots is an important phenomenon in various pathological states associated with a dry eye.


Asunto(s)
Modelos Biológicos , Lágrimas/fisiología , Epitelio Corneal/fisiología , Humanos , Matemática , Tensión Superficial , Lágrimas/química , Viscosidad
8.
FEMS Immunol Med Microbiol ; 28(4): 319-27, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10891656

RESUMEN

We evaluated the bactericidal antibody response to Neisseria meningitidis serogroup B in convalescent patients (n=65) from bacterial meningitis. Patients infected with B meningococci were stratified according to their vaccination status (Cuban BC vaccine) into group 1 (immunized) (n=12) and group 2 (non-immunized) (n=15). The results suggested that antibody titers > or =2 (log(2)) indicate a specific immune response to N. meningitidis. In group 1, 64% of patients had a significant antibody titer (> or =2) in their acute sera against a B:4:P1.15 strain, compared to only 21% of group 2 patients. All patients from group 1 without bactericidal antibodies in their acute sera had a significant increase (at least 2-fold increase in log(2) titers) in antibody titers in their convalescent sera, in contrast, to only 27% of patients from group 2 (P=0.06). Using mutant strains lacking OMP1 or OMP5, it was shown that OMP1 was an important antigen recognized by immunized patients but not by non-immunized patients.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Vacunas Bacterianas/inmunología , Meningitis Meningocócica/inmunología , Neisseria meningitidis/inmunología , Adolescente , Adulto , Proteínas de la Membrana Bacteriana Externa/inmunología , Niño , Preescolar , Humanos , Lactante , Meningitis Meningocócica/prevención & control , Vacunas Meningococicas , Persona de Mediana Edad , Neisseria meningitidis/clasificación , Serotipificación , Vacunación
9.
Mol Ecol ; 9(6): 699-708, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10849286

RESUMEN

The routes through which Norway spruce recolonized the Alps after the last ice age were investigated at the genetic level. Seven populations along the Alpine range plus one Apennine population were characterized for seven sequence-characterized amplified region (SCAR) loci, detecting an overall FST = 0.118. This rather high value for forest species reflects an uneven distribution of genetic variability, and was analysed through different statistical methods. Alternative hypotheses were tested under the isolation-by-distance model and using the analysis of molecular variance (AMOVA) frame. We conclude that the hypothesis of the existence of a glacial refugium in the Apennines should be rejected, while a putative relict population is identified in the Maritime Alps. The Alpine range of Norway spruce appears to be split in two parts across a north-south line. The results are discussed in comparison with data based on morphological markers, isozymes, chloroplast microsatellites and mitochondrial markers.


Asunto(s)
Marcadores Genéticos , Genética de Población , Árboles/genética , Variación Genética , Italia , Desequilibrio de Ligamiento , Modelos Genéticos , Noruega , Lugares Marcados de Secuencia , Árboles/fisiología
10.
Heredity (Edinb) ; 84 ( Pt 3): 303-10, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10866532

RESUMEN

QTL mapping with statistical likelihood-based procedures or asymptotically equivalent regression methods is usually carried out in a univariate way, even if many traits were observed in the experiment. Some proposals for multivariate QTL mapping by an extension of the maximum likelihood method for mixture models or by an application of the canonical transformation have been given in the literature. This paper describes a method of analysis of multitrait data sets, aimed at localization of QTLs contributing to many traits simultaneously, which is based on the linear model of multivariate multiple regression. A special form of the canonical analysis is employed to decompose the test statistic for the general no-QTL hypothesis into components pertaining to individual traits and individual, putative QTLs. Extended linear hypotheses are used to formulate conjectures concerning pleiotropy. A practical mapping algorithm is described. The theory is illustrated with the analysis of data from a study of maize drought resistance.


Asunto(s)
Modelos Genéticos , Análisis Multivariante , Carácter Cuantitativo Heredable , Genes de Plantas , Ligamiento Genético , Marcadores Genéticos , Modelos Estadísticos , Fenotipo , Recombinación Genética , Zea mays/genética
11.
Dev Genet ; 25(3): 237-44, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10528264

RESUMEN

MADS-box genes have been shown to play a major role in defining plant architecture. Recently, several MADS-box genes have been reported that are highly expressed in the ovule. However, only for the Petunia genes FBP7 and FBP11 has a function in defining ovule identity been shown. We have isolated a rice MADS-box gene named OsMADS13. Expression analysis has shown that this gene is highly expressed in developing ovules. In order to facilitate a detailed characterization of rice ovule-expressed genes, a comprehensive morphological description of ovule development in rice has been performed. The predicted amino acid sequence of OsMADS13 shows significant homology with ZAG2, a maize MADS-box gene, which is also expressed mainly in the ovule. Mapping of the gene in the rice genome showed that it is located on chromosome 12, which is syntenic to two maize regions where ZAG2 and its paralogous gene ZMM1 have been mapped. Our results suggest that OsMADS13 is the ortholog of ZAG2 and ZMM1 and might play a role in rice ovule and seed development.


Asunto(s)
Proteínas de Unión al ADN/genética , Oryza/genética , Proteínas de Plantas/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Mapeo Cromosómico , Genoma de Planta , Proteínas de Dominio MADS , Datos de Secuencia Molecular
12.
Vaccine ; 17(23-24): 2951-8, 1999 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-10462229

RESUMEN

Neisseria meningitidis serogroup C polysaccharide (PS C) was conjugated to serogroup B outer membrane vesicles (OMV) in order to test the possibility of obtaining a bivalent group B and C meningococcus vaccine. The conjugate and controls were injected intraperitoneally into groups of ten mice with boosters on days 14 and 28 after the primary immunization. The following groups were used as control: (i) PS C; (ii) PS C plus OMV; (iii) OMV; and (iv) saline. The serum collected on days 0, 14, 28 and 42 were tested by enzyme-linked immunosorbent assay (ELISA) for PS C and OMV, and by complement mediated bactericidal assay against serogroups B and C. ELISA for PS C as well as bactericidal titres against serogroup C meningococci of the conjugated vaccine increased eight-fold (ELISA) and 32 fold (bactericidal) after 42 days in comparison with the PS C control group. ELISA for OMV and bactericidal titre against serogroup B meningococci of the conjugate showed no significant difference in comparison with the OMV containing controls. Furthermore, Western Blot assay of the conjugate immune serum did not bind OMV class four protein which is related to the complement dependent antibody suppressor. The results indicate that the PS C-OMV conjugate could be a candidate for a bivalent vaccine toward serogroups B and C meningococci.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/inmunología , Neisseria meningitidis/inmunología , Polisacáridos Bacterianos/inmunología , Animales , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/aislamiento & purificación , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Vacunas Bacterianas/química , Ensayo de Inmunoadsorción Enzimática , Immunoblotting , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/inmunología , Masculino , Vacunas Meningococicas , Ratones , Ratones Endogámicos C3H , Polisacáridos Bacterianos/aislamiento & purificación , Vacunas Conjugadas/química , Vacunas Conjugadas/inmunología
13.
Surv Ophthalmol ; 43 Suppl 1: S142-50, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10416757

RESUMEN

Most therapy for glaucoma is directed at the management of the intraocular pressure (IOP). Conventional wisdom holds that excessive pressure within the eye leads to the ganglion cell loss/optic nerve damage seen in this disease. Both glutamate and elevated IOP can selectively damage the retinal ganglion cells in the mammalian eye. We have identified an elevated level of glutamate in the vitreous humor of glaucoma patients (27 microM as compared to 11 microM in the control population). This concentration of glutamate suffices--on its own--to kill retinal ganglion cells. It is plausible that the IOP may represent an initial insult that precipitates the production of excessive glutamate. Therefore, even if glutamate elevation is an epiphenomenon associated with the course of the disease, it may contribute to ganglion cell loss in humans. Lowering the IOP may slow down glutamate production, but if nothing is done to block the toxic effects of glutamate as well, visual loss may result despite excellent IOP control. If interventions can be found to retard the production or toxic effects of glutamate, it may be possible to slow glaucomatous visual loss.


Asunto(s)
Glaucoma/metabolismo , Ácido Glutámico/metabolismo , Enfermedades del Nervio Óptico/metabolismo , Animales , Apoptosis/efectos de los fármacos , Inhibidores Enzimáticos/uso terapéutico , Glaucoma/complicaciones , Glaucoma/tratamiento farmacológico , Humanos , Presión Intraocular , N-Metilaspartato/antagonistas & inhibidores , N-Metilaspartato/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Enfermedades del Nervio Óptico/tratamiento farmacológico , Enfermedades del Nervio Óptico/etiología , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Cuerpo Vítreo/metabolismo
14.
Invest Ophthalmol Vis Sci ; 40(5): 983-9, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10102296

RESUMEN

PURPOSE: There is growing evidence that the neuronal pathology seen with HIV-1 is mediated, at least in part, through an excitotoxic/free radical pathway. Nitric oxide (NO) plays a critical role in the nervous system, in both normal and pathologic states, and appears to be involved in a variety of excitotoxic pathways. Whether isoforms of nitric oxide synthase (NOS) are involved in gp120-mediated neuronal loss in the retina was therefore explored. METHODS: To determine which (if any) of the various isoforms of NOS are critical in gp120-mediated damage in the retina, neuronal NOS-deficient [nNOS(-/-)], endothelial NOS-deficient [eNOS(-/ -)], and immunologic NOS-deficient [iNOS(-/-)] mice were subjected to intravitreal injections of gp120. RESULTS: Retinal ganglion cells in the nNOS(-/-) mouse were relatively resistant to gp120, manifesting attenuation of gp120-induced injury compared with wild-type mice. The iNOS(-/-) and eNOS(-/-) mice were as susceptible to gp120 toxicity as control animals. NOS inhibitors were protective against this toxicity. CONCLUSIONS: The presence of nNOS is a prerequisite for the full expression of gp120-mediated loss in the retina; eNOS and iNOS do not appear to play a significant role.


Asunto(s)
Proteína gp120 de Envoltorio del VIH/toxicidad , VIH-1 , Óxido Nítrico Sintasa/fisiología , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Recuento de Células , Muerte Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Mutantes , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo I , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Nitroarginina/farmacología , Células Ganglionares de la Retina/enzimología , Células Ganglionares de la Retina/patología
15.
Invest Ophthalmol Vis Sci ; 40(3): 813-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10067991

RESUMEN

PURPOSE: Muscarinic agents reduce intraocular pressure by enhancing aqueous outflow, probably by stimulating ciliary muscle contraction. However, pilocarpine is a well characterized neurotoxin and is widely used to generate animal seizure models. It was therefore investigated whether pilocarpine was also toxic to retinal ganglion cells. METHODS: Dissociated whole retinal preparations were prepared from postnatal day 16 to 19 rats. Retinal ganglion cells had been previously back-labeled with a fluorescent tracer. Retinal cells were incubated with pilocarpine, lithium, and inositol derivatives, and viability of the retrogradely labeled retinal ganglion cells was assayed after 24 hours. RESULTS: Pilocarpine was toxic to retinal ganglion cells in a dose-dependent fashion. This toxicity was potentiated by lithium and blocked by epi- and myo-inositol. CONCLUSIONS: Pilocarpine is toxic to retinal ganglion cells in a mixed culture assay. This toxicity appears to depend on the inositol pathway and is similar to its mode of action in other neurons. However, 0.4 mM pilocarpine (the lowest concentration that did not affect ganglion cell survival) is roughly 1000-fold higher than the vitreal concentration and 20-fold higher than the scleral concentration that can be obtained with topical administration of 2% pilocarpine in the rabbit eye.


Asunto(s)
Pilocarpina/toxicidad , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inositol/farmacología , Litio/farmacología , Ratas , Ratas Long-Evans
16.
Plant Mol Biol ; 38(6): 1147-60, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9869420

RESUMEN

Hazelnut (Corylus avellana L.) is a species of economic interest that shows a peculiar floral biology. Unlike most of the angiosperms, which produce ovules during floral development such that they are ready for pollen at anthesis, hazelnut ovary development is delayed and triggered by compatible pollination. In order to elucidate the mechanisms regulating this unusual process and the role of the MADS box genes in ovary development, a cDNA library from pollinated styles of hazelnut was screened with a mixture of MADS box genes from different plant species. CaMADS1 (Corylus avellana MADS box), a floral-specific MADS box gene, was isolated, and characterized as belonging to the sub-family of the AGAMOUS genes. Northern blot, RT-PCR analyses and in situ hybridization experiments show a precise correlation between ovary development and CaMADS1 expression, indicating a role of this MADS box gene in the processes of floral organogenesis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas de Homeodominio/genética , Nueces/genética , Filogenia , Secuencia de Aminoácidos , Secuencia de Bases , Cartilla de ADN , Proteínas de Unión al ADN , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/química , Proteínas de Dominio MADS , Datos de Secuencia Molecular , Nueces/crecimiento & desarrollo , Nueces/metabolismo , Proteínas de Plantas , Tallos de la Planta , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Semillas , Factores de Transcripción
17.
Infect Immun ; 66(10): 4755-61, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9746575

RESUMEN

Pre- and postvaccination serum samples from 77 children aged 2 to 6 years, who received the Cuban BC vaccine (B:4:P1.15), were analyzed for bactericidal antibodies against a local B:4:P1.15 strain (N44/89). Sera from 16 individuals with bactericidal antibodies against the B:4:P1.15 strain were tested against 23 Brazilian isolates. These include B:4 strains of distinct serosubtypes: P1.15, P1.7,1, P1.3, P1.9, P1.nt, and a B:8,19,23:P1.16 strain. A Cuban B:4:P1.15 strain (Cu385/83) was also included in the study. The specificities of bactericidal antibodies were analyzed by using mutant strains lacking a class 1 protein (PorA protein) or a class 5 protein or both. The results indicated that PorA and class 5 proteins are the main targets recognized by the bactericidal antibodies of vaccinees. Nonetheless, a complex pattern of recognition by bactericidal antibodies was found, and vaccinees were grouped according to antibody specificity. Antibodies from some individuals recognized PorA of serosubtype P1.15. However, antibodies from these individuals could not kill all P1.15 strains tested. Antibodies from a second group recognized both PorA and class 5 proteins, and antibodies from a third group recognized an as yet unidentified target antigen. The results demonstrate the importance of determining the fine epitope specificity of bactericidal antibodies to improve the existing vaccines against B meningococci.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Especificidad de Anticuerpos , Proteínas de la Membrana Bacteriana Externa/uso terapéutico , Vacunas Bacterianas/uso terapéutico , Infecciones Meningocócicas/prevención & control , Vacunación , Brasil , Niño , Preescolar , Humanos , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas , Datos de Secuencia Molecular , Mutación , Neisseria meningitidis/clasificación , Neisseria meningitidis/genética , Porinas/genética , Serotipificación
18.
Vision Res ; 38(10): 1489-94, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9667013

RESUMEN

Nitrates have been a major part of the internist's pharmacopoeia for more than 100 years, predominantly for the relief of anginal symptoms. The effects of nitroglycerin on the eye and specifically on intraocular pressure has been investigated with diverse results. However, nitroglycerin may also serve to protect retinal ganglion cells against glutamate mediated toxicity--a form of cell death that may be critical in glaucomatous blindness. Consequently, we therefore sought to evaluate whether nitroglycerin preparations, taken for non-ophthalmic reasons, had an effect on glaucomatous damage.


Asunto(s)
Glaucoma de Ángulo Abierto/complicaciones , Nitroglicerina/farmacología , Enfermedades del Nervio Óptico/prevención & control , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Humanos , Presión Intraocular , Masculino , Enfermedades del Nervio Óptico/etiología , Factores de Tiempo , Trastornos de la Visión/etiología , Campos Visuales
19.
Mol Gen Genet ; 253(5): 615-23, 1997 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-9065695

RESUMEN

With the aim of elucidating the complex genetic system controlling flower morphogenesis in cereals, we have characterized two rice and two sorghum MADS box genes isolated from cDNA libraries made from developing inflorescences. The rice clones OsMADS24 and OsMADS45, which share high homology with the Arabidopsis AGL2 and AGL4 MADS box genes, are expressed in the floral meristem, in all the primordia, and in mature floral organs. High expression levels have also been found in developing kernels. The sorghum clone SbMADS1 is also homologous to AGL2 and AGL4: expression analysis and mapping data suggest that it is the ortholog of OsMADS24. The pattern of expression of SbMADS2, the other sorghum MADS box gene, suggests that it may play a role as a meristem identity gene, as does AP1 in Arabidopsis, to which it shows considerable homology. The four genes have been mapped on a rice RFLP genetic map: the results are discussed in terms of synteny among cereals.


Asunto(s)
Grano Comestible/genética , Genes de Plantas , Oryza/genética , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Northern Blotting , Mapeo Cromosómico , Grano Comestible/crecimiento & desarrollo , Expresión Génica , Hibridación in Situ , Datos de Secuencia Molecular , Morfogénesis/genética , Oryza/crecimiento & desarrollo , Polimorfismo de Longitud del Fragmento de Restricción , Homología de Secuencia de Aminoácido
20.
Plant Physiol ; 112(4): 1595-1600, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12226466

RESUMEN

Glutathione S-transferases (GSTs) are a family of isozymes that catalyze the conjugation of glutathione to several xenobiotics, including a number of important herbicides. Several GST isoforms have been identified in maize (Zea mays L.). In this study we focused on three isoforms, GST I, II, and IV, derived from homo-or heterodimerization of two subunits GST-29 and GST-27, which have been shown to be responsible for reactivity to alachlor. The expression of these isoforms was examined in three inbred lines of maize that showed tolerance, susceptibility, and intermediate resistance to alachlor (2-Cl-N-[2,6-diethylphenyl]-N-[methoxymethyl]acetamide) treatment. The different isoforms were separated by anion-exchange chromatography and subunits were quantified by western blot analysis. GST assays were performed against both 1-Cl-2,4-dinitrobenzene and alachlor. This analysis showed that the susceptible and intermediate lines exhibit impaired function in the GST-27 and GST-29 subunits, respectively. In addition, this study suggests that GST IV is the principal, detoxifying enzyme for alachlor, although GST I and II are required to achieve tolerance to high rates of the herbicide.

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