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1.
Rev. argent. dermatol ; 101(2): 21-30, jun. 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1125819

RESUMO

Resumen El prurito durante el embarazo, es el síntoma dermatológico más frecuente de consulta en esta población. Cuando esta condición es severa puede interferir en el sueño, alterar el ánimo, afectando seriamente la calidad de vida. Sus causas pueden ser tan variadas como reacciones de hipersensibilidad, enfermedades sistémicas o dermatosis específicas del embarazo, dentro de las cuales destaca el penfigoide gestacional, única enfermedad autoinmune exclusiva del embarazo, ya que puede tener repercusión en el feto y la madre. El objetivo de esta revisión es actualizar el conocimiento actual del penfigoide gestacional a partir de un caso clínico con componentes atípicos que se deben tener en consideración ante la sospecha diagnóstica.


Abstract Pruritus during pregnancy is the most frequent dermatological symptom of consultation in this population. When this condition is severe it can interfere with sleep, alter mood, seriously affecting the quality of life. Its causes can be as varied as hypersensitivity reactions, systemic diseases or specific dermatoses of pregnancy, among which gestational pemphigoid, the only autoimmune disease exclusive of pregnancy, as it can have an impact on the fetus and the mother. The objective of this review is to update the current knowledge of gestational pemphigoid from a clinical case with atypical components that should be taken into consideration in case of diagnostic suspicion.

2.
Actas dermo-sifiliogr. (Ed. impr.) ; 110(3): 220-226, abr. 2019. graf, ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-181712

RESUMO

Antecedentes y objetivo: Las metástasis cutáneas (MC) constituyen el 2% de los tumores cutáneos, y su incidencia varía entre el 0,7% y el 9% de los pacientes con cáncer. El objetivo de este estudio es describir y analizar las características demográficas, clínicas e histopatológicas de las MC en población consultante de 2 hospitales de la Región Metropolitana. Material y método: Estudio retrospectivo, descriptivo, analítico, observacional y transversal. Se revisaron los informes histopatológicos, fichas, láminas histopatológicas y fechas de defunción de los casos con diagnóstico de MC del servicio de anatomía patológica de 2 hospitales de la Región Metropolitana entre los años 2005 y 2017. Resultados: Se incluyeron 96 casos de MC. El 60,42% fueron mujeres y el 39,58% hombres. La edad promedio al momento del diagnóstico fue de 67,95 ± 13,74 años, con un rango de 28 a 96 años. La fuente neoplásica primaria más frecuente fue melanoma en el 27,08% (n = 26), seguido de carcinoma de mama 18,75% (n = 18) y adenocarcinoma 15,63% (n = 15). La mediana de tiempo entre el diagnóstico del tumor y la metástasis cutánea fue de 9 meses. Los pacientes con MC de melanoma presentaron una mayor sobrevida que aquellos con metástasis de otro origen (p < 0,05). El examen histopatológico de 91 láminas mostró con mayor frecuencia una infiltración difusa del tejido con células tumorales y con baja frecuencia la presencia de permeación vascular. Conclusiones: Los resultados obtenidos se asemejan a la realidad internacional. Las MC son poco frecuentes, constituyendo una rara manifestación de neoplasias internas, se presentan principalmente a edades avanzadas y en ambos sexos por igual


Background and objective: Cutaneous metastases (CMs) account for 2% of skin tumors and their incidence varies between 0.7% and 9% in patients with cancer. The objective of this study was to describe and analyze the demographic, clinical, and histopathologic characteristics of CM in patients who visited 2 hospitals in the Santiago de Chile metropolitan region. Material and method: We performed a retrospective, descriptive, analytical, observational, cross-sectional study. We reviewed the pathology reports, patient records, pathology slides, and dates of death for diagnosed cases of CM from the anatomic pathology departments of 2 hospitals in the Santiago de Chile metropolitan region between 2015 and 2017. Results: Ninety-six patients with CM were included in the study; 60.42% were women and 39.58% were men. The mean (SD) age was 67.95 (13.74) years, with a range of 28 to 96 years. The most common primary tumor was melanoma in 27.08% of cases (n = 26), followed by breast cancer (18.75%, n = 18), and adenocarcinoma (15.63%, n = 15). The median time between diagnosis of the tumor and cutaneous metastasis was 9 months. Patients with CM of melanoma had a higher survival rate than patients with metastasis of other primary tumors (P < .05). A histopathologic study of 91 slides showed that diffuse infiltration of the tissue with tumor cells was the most common pattern and vascular invasion was rare. Conclusions: The results are similar to those found worldwide. CM is a rare manifestation of internal tumors. It presents mainly at an advanced age and is equally prevalent in both sexes


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias Cutâneas/epidemiologia , Metástase Neoplásica/patologia , Melanoma/epidemiologia , Neoplasias Cutâneas/patologia , Chile/epidemiologia , Estudos Retrospectivos , Epidemiologia Descritiva , Estudos Transversais
3.
Actas Dermosifiliogr (Engl Ed) ; 110(3): 220-226, 2019 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30577946

RESUMO

BACKGROUND AND OBJECTIVE: Cutaneous metastases (CMs) account for 2% of skin tumors and their incidence varies between 0.7% and 9% in patients with cancer. The objective of this study was to describe and analyze the demographic, clinical, and histopathologic characteristics of CM in patients who visited 2 hospitals in the Santiago de Chile metropolitan region. MATERIAL AND METHOD: We performed a retrospective, descriptive, analytical, observational, cross-sectional study. We reviewed the pathology reports, patient records, pathology slides, and dates of death for diagnosed cases of CM from the anatomic pathology departments of 2 hospitals in the Santiago de Chile metropolitan region between 2015 and 2017. RESULTS: Ninety-six patients with CM were included in the study; 60.42% were women and 39.58% were men. The mean (SD) age was 67.95 (13.74) years, with a range of 28 to 96 years. The most common primary tumor was melanoma in 27.08% of cases (n=26), followed by breast cancer (18.75%, n=18), and adenocarcinoma (15.63%, n=15). The median time between diagnosis of the tumor and cutaneous metastasis was 9 months. Patients with CM of melanoma had a higher survival rate than patients with metastasis of other primary tumors (P<.05). A histopathologic study of 91 slides showed that diffuse infiltration of the tissue with tumor cells was the most common pattern and vascular invasion was rare. CONCLUSIONS: The results are similar to those found worldwide. CM is a rare manifestation of internal tumors. It presents mainly at an advanced age and is equally prevalent in both sexes.


Assuntos
Neoplasias Cutâneas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Chile/epidemiologia , Estudos Transversais , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Fatores de Tempo , População Urbana
4.
Bio sci (En linea) ; 2(3): 1-10, 2019. ilus.
Artigo em Espanhol | LILACS, LIBOCS | ID: biblio-1050347

RESUMO

Se realizó un estudio de picaduras de aracnomrofos en la ciudad de Sucre (Chuquisaca). El método comprendió el uso de encuestas semiestructuradas, donde se consultó sobre la percepción que tienen, sintomatologías y conocimiento local sobre métodos de curación. Los resultados obtenidos evidencian que la mayoría tiene fobia hacia los arácnidos. El conocimiento local, permite conocer los diferentes tipos de arañas y escorpiones que residen en los domicilios. Se describe los síntomas que causan debido al efecto de las picadas, además de los métodos convencionales y naturales de curación.


We study of pitting Arachnomorph´s was held in the city of Sucre (Chuquisaca). The method realized using semistructured interviews, which were consulted on the perception, symptom and local knowledge of healing methods. The results show that most have phobia of arachnids. Local knowledge, allows to know the different types of spiders and scorpions that live in the homes. They are causing symptoms due to the effect of bites and of natural and using the conventional and natural healing methods.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Transtornos Fóbicos , Mordeduras e Picadas , Inquéritos e Questionários , Métodos
5.
Rev. argent. dermatol ; 98(3): 0-0, set. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-897379

RESUMO

El liquen amiloideo es un tipo de amiloidosis cutánea primaria localizada, de etiología desconocida. Generalmente afecta a adultos, siendo más frecuente en ciertos grupos étnicos. Clínicamente se manifiesta por pápulas pruriginosas, frecuentemente localizadas en miembros inferiores. Presentamos el caso de una mujer de 50 años, con un historial de dos años caracterizado por pápulas agminadas en piernas, que tras la realización de una biopsia se diagnosticó liquen amiloideo.


Amyloid lichen is a type of localized primary cutaneous amyloidosis of unknown etiology. It usually affects adults being more frequent in certain ethnic groups. Clinically it is manifested by pruritic papules frequently located in lower limbs. We present the case of a 50-year-old woman, with a two-year history characterized by papules agminated in the legs that diagnosed amyloid lichen after biopsy.

7.
Eur J Microbiol Immunol (Bp) ; 5(2): 164-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26185685

RESUMO

Through a cross-sectional study design, 150 women attending public health centers with a history of stillbirths were examined for anti-Toxoplasma gondii IgG and IgM antibodies in Durango City, Mexico. Bivariate and multivariate analyses were used to assess the association of T. gondii seropositivity with the characteristics of the women with stillbirth history. Of the 150 women (mean age: 32.09 ± 9.16 years) studied, 14 (9.3%) had anti-T. gondii IgG antibodies and six (42.9%) of them were also positive for anti-T. gondii IgM antibodies. Multivariate analysis showed that T. gondii seropositivity was associated with high frequency (4-7 days a week) of eating meat (OR = 5.52; 95% CI: 1.48-20.59; P = 0.01), history of lymphadenopathy (OR = 4.52; 95% CI: 1.14-17.82; P = 0.03), and history of surgery (OR = 8.68; 95% CI: 1.04-72.15; P = 0.04). This is the first study on the seroepidemiology of T. gondii infection in women with a history of stillbirths in Mexico. The association of T. gondii exposure with a history of surgery warrants for further research. Risk factors for T. gondii infection found in the present survey may help to design optimal educational programs to avoid T. gondii infection.

8.
Eur J Microbiol Immunol (Bp) ; 4(2): 117-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24883197

RESUMO

Through a cross-sectional study design, 326 women with a history of miscarriage were examined for anti-Toxoplasma gondii IgG and IgM antibodies in Durango City, Mexico. Prevalence association with sociodemographic, clinical, and behavioral characteristics in women with miscarriage was also investigated. Twenty-two (6.7%) of the 326 women studied had anti-T. gondii IgG antibodies and two (0.6%) were also positive for anti-T. gondii IgM antibodies. Seroprevalence of T. gondii infection was not influenced by age, birth place, occupation, educational level, or socioeconomic status. In contrast, logistic regression showed that T. gondii exposure was associated with consumption of raw or undercooked meat (OR = 6.84; 95% CI: 1.04-44.95; P = 0.04) and consumption of chicken brains (OR = 18.48; 95% CI: 1.26-269.43; P = 0.03). This is the first study on the seroepidemiology of T. gondii infection in women with a history of miscarriage in Northern Mexico. Of interest, we also observed an association of T. gondii exposure with consumption of chicken brains. Contributing factors for T. gondii exposure found in the present study should be taken into consideration for public health measures to avoid infection with T. gondii and its sequelae.

9.
Biotech Histochem ; 86(4): 232-41, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20302548

RESUMO

The first approach to assessing male fertility is to study a spermiogram, where special attention is given to sperm count, motility and morphology, while less attention is given to other cells in the ejaculate. Normal spermatogenesis requires a balance between cell death and proliferation; therefore, the number of germ cells (GC) in the ejaculate is less than the number of sperm. We propose a new index for altered spermatogenesis, i.e., the rate GC/sperm. We investigated a patient with oligozoospermia and a GC/sperm ratio greater than one, which indicated that spermatogenesis had been damaged. Complementary cytological tests were employed to characterized GC status: Papanicolaou stain, transmission electronic microscopy (TEM), vitality test, AgNOR and TUNEL assay. We also correlated cell morphology with ultrastructure studies that showed apoptosis. Nuclear apoptosis is characterized by vacuolization, misshapen nuclei, and "half moon," dispersed, uncondensed, disrupted and smudged chromatin. Cytoplasmic apoptosis is characterized by vacuolization, cytoplasmic protrusions, lamellar bodies, and swollen endoplasmic reticulum and mitochondria. To date, only testicular biopsy has been used to diagnose complete or incomplete testicular arrest. Our investigation is the first to determine a cytological feature in semen samples that could be used as a biological marker for abnormal spermatogenesis and for predicting the transition from oligospermia to azoospermia.


Assuntos
Apoptose/fisiologia , Azoospermia/patologia , Células Germinativas/patologia , Contagem de Espermatozoides/métodos , Motilidade dos Espermatozoides , Espermatozoides/patologia , Tomografia com Microscopia Eletrônica , Células Germinativas/metabolismo , Células Germinativas/ultraestrutura , Humanos , Infertilidade Masculina/patologia , Masculino , Oligospermia/patologia , Espermatogênese , Espermatozoides/metabolismo , Espermatozoides/ultraestrutura
10.
Biotech Histochem ; 84(6): 321-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19634066

RESUMO

We propose that evaluation of protein tyrosine phosphorylation (TP) status in ejaculated spermatozoa under capacitating conditions in an experiment that mimics "in vitro" the physiology of sperm from ejaculation through the female genital tract could potentially be used as a prognostic test for functional competence of sperm in fertilization. Our purpose was to elucidate whether there is a relation between conventional sperm parameters, occurrence of TP and pregnancy outcome obtained from intrauterine insemination (IUI). Semen samples were analyzed according to WHO criteria. TP levels were determined by immunocytochemistry under four different conditions: 1) ejaculated sperm, 2) postselection sperm, 3) postselection sperm incubated 5 h at 37 degrees C and 5% CO(2), and 4) postselection sperm incubated overnight at 37 degrees C and 5% CO(2). Data on sperm tyrosine phosphorylated proteins did not correlate with sperm concentration, progressive motility or normal sperm morphology. TP increased under capacitating conditions and showed a time dependent pattern except for five outlier cases. IUI was performed in 12 selected couples who had neither female nor male infertility factors. The three pregnancies had a time dependent pattern for TP. Of the unsuccessful cases, one had an outlier TP pattern. It appears that a TP time dependent pattern is necessary for fertilization.


Assuntos
Andrologia , Imuno-Histoquímica/métodos , Laboratórios , Espermatozoides/metabolismo , Tirosina/metabolismo , Ejaculação , Feminino , Fertilização in vitro , Humanos , Infertilidade Masculina/metabolismo , Masculino , Fosforilação , Gravidez , Resultado da Gravidez , Prognóstico , Contagem de Espermatozoides , Espermatozoides/citologia , Espermatozoides/fisiologia
11.
Arch Androl ; 49(5): 343-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12893510

RESUMO

Spermatozoa travel a long distance to meet and fertilize the oocyte, so sperm motility is a requisite for normal fertilization. Asthenozoospermia, or low sperm motility, is a common cause of human male infertility. This is a retrospective study (1992-1999) to document the prevalence of this pathology in infertile men and to clarify the probable factors associated to its etiology. The prevalence was 18.71% for asthenozoospermia and 63.13% for asthenozoospermia associated with oligo- and/or teratozoo-spermia; thus, 81.84% of the studied samples had altered motility. Leukocytospermia, the ratio of germ cells/sperm, anti-sperm antibodies, consistency, biochemical markers of accessory sex glands, and sperm response after swim-up were studied in normospermic (N), asthenozoospermic (A), and combined asthenozoospermic (C) samples. No significant difference was found in the frequency of leukocytospermia among groups. The rate of germ cells/(spermatozoa + germ cells) between C and N (p < .01) and C and A (p < .01) was statistically different, while no difference was found on comparing N and A. MAR-test over 40% was found in 6% of the A samples and 7.6% of the C, while no positive values were observed in the N group. The percentage of hyperviscous samples was higher in the low sperm motility samples than in the normal group. Data on concentration of the biochemical markers seem to be decreased in asthenozoospermia. Pure and combined asthenozoo-spermia showed different behavior in sperm recovery after swim-up. Two different asthenozoospermias could be defined: the pure one where sperm environment is involved (immunological factor, hyperviscosity, and secretory gland function) and the combined, where the testis is comprised.


Assuntos
Oligospermia , Maturação do Esperma/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/patologia , Fosfatase Ácida , Anticorpos/imunologia , Argentina/epidemiologia , Ácido Cítrico/análise , Frutose/análise , Humanos , Contagem de Leucócitos , Leucocitose/complicações , Leucocitose/fisiopatologia , Masculino , Oligospermia/epidemiologia , Oligospermia/etiologia , Oligospermia/fisiopatologia , Proteínas Tirosina Fosfatases/análise , Estudos Retrospectivos , Sêmen/química , Espermatozoides/imunologia
12.
Rev Med Chil ; 129(9): 1044-50, 2001 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-11725468

RESUMO

BACKGROUND: Pyoderma gangrenosum is an ulcerative disease of the skin of unknown cause and generally associated to systemic illnesses. It requires an aggressive systemic therapy and there is little information about its long term evolution. AIM: To report the clinical features of patients with pyoderma gangrenosum. PATIENTS AND METHODS: Eleven patients (10 female) aged 27 to 81 years old with pyoderma gangrenosum are reported. All had a pathological study. Patients were followed up for a mean of 60 months. RESULTS: The lesions were located in the lower limbs in 8 patients. Pathological study showed neutrophyl infiltrates in nine patients. Three patients had inflammatory bowel disease [corrected]. During the follow up, the disease recurred in multiple occasions, in six patients, after treatment with steroids or sulphones, and one patient has had permanently active lesions. CONCLUSIONS: Pyoderma gangrenosum appears mostly in the lower limbs and has a high recurrence rate.


Assuntos
Dermatoses da Perna/patologia , Pioderma Gangrenoso/patologia , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Dapsona/uso terapêutico , Feminino , Seguimentos , Humanos , Dermatoses da Perna/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Pioderma Gangrenoso/tratamento farmacológico , Sulfassalazina/uso terapêutico
13.
FEBS Lett ; 456(2): 269-73, 1999 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-10456322

RESUMO

The chaperonins are evolutionarily conserved essential cellular proteins that help folding newly synthesized or translocated proteins, spending ATP. We present here the molecular analysis of the hsp60 gene promoter region and of two Drosophila hsp60 ethyl methane sulfonate embryonic lethal alleles that have an identical phenotype. No heat shock element sequences were found in the 5' region, supporting previous data (Kozlova, T. et al., 1997) which suggests that mitochondrial Drosophila melanogaster HSP60.1 is not heat inducible. By sequencing the lethal allele's entire open reading frame (ORF), we found a C-T transition in the hsp60F409 allele that produces a serine to leucine change, apparently distorting the protein equatorial domain structure. No changes were found in the hsp60G93 ORF. However, an analysis of the heterogeneous nuclear RNA levels showed a reduction of the hsp60 transcript in hsp60G93 flies as compared to the wild-type. These data suggest that although the defects in the hsp60 gene produced by these alleles are at different levels, both behave as null mutations.


Assuntos
Chaperonina 60/genética , Drosophila melanogaster/genética , Genes de Insetos , Alelos , Animais , Sequência de Bases , Chaperonina 60/química , Clonagem Molecular , DNA Complementar/genética , Drosophila melanogaster/metabolismo , Metanossulfonato de Etila , Genes Letais , Modelos Moleculares , Dados de Sequência Molecular , Mutagênicos , Fases de Leitura Aberta , Mutação Puntual , Regiões Promotoras Genéticas , Conformação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Am J Public Health ; 89(7): 1054-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10394315

RESUMO

OBJECTIVES: This study examined the extreme medical unemployment and underemployment in the urban areas of Mexico. The conceptual and methodological approach may be relevant to many countries that have experienced substantial increases in the supply of physicians during the last decades. METHODS: On the basis of 2 surveys carried out in 1986 and 1993, the study analyzed the performance of physicians in the labor market as a function of ascription variables (social origin and gender), achievement variables (quality of medical education and specialty studies), and contextual variables (educational generation). RESULTS: The study reveals, despite some improvement, persistently high levels of open unemployment, qualitative underemployment (i.e., work in activities completely outside of medicine), and quantitative underemployment (i.e., work in medical activities but with very low levels of productivity and remuneration). The growing proportion of female doctors presents new challenges, because they are more likely than men to be unemployed and underemployed. CONCLUSIONS: While corrective policies can have a positive impact, it is clear that decisions regarding physician supply must be carefully considered, because they have long-lasting effects. An area deserving special attention is the improvement of professional opportunities for female doctors.


Assuntos
Emprego/estatística & dados numéricos , Médicos/provisão & distribuição , População Urbana , Feminino , Humanos , Renda , Masculino , Medicina , México , Médicas/provisão & distribuição , Fatores Sexuais , Classe Social , Especialização , Desemprego/estatística & dados numéricos
17.
J Virol ; 71(9): 6749-56, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9261399

RESUMO

The infectivity of most animal rotaviruses is dependent on the interaction of the virus spike protein VP4 with a sialic acid (SA)-containing cell receptor, and the SA-binding domain of this protein has been mapped between amino acids 93 and 208 of its trypsin cleavage fragment VP8. To identify which residues in this region are essential for the SA-binding activity, we performed alanine mutagenesis of the rotavirus RRV VP8 expressed in bacteria as a fusion polypeptide with glutathione S-transferase. Tyrosines were primarily targeted since tyrosine has been involved in the interaction of other viral hemagglutinins with SA. Of the 15 substitutions carried out, 10 abolished the SA-dependent hemagglutination activity of the protein, as well as its ability to bind to glycophorin A in a solid-phase assay. However, only alanine substitutions for tyrosines 155 and 188 and for serine 190 did not affect the overall conformation of the protein, as judged by their interaction with a panel of conformationally sensitive neutralizing VP8 monoclonal antibodies (MAbs). These findings suggest that these three amino acids play an essential role in the SA-binding activity of the protein, presumably by interacting directly with the SA molecule. The predicted secondary structure of VP8 suggests that it is organized as 11 beta-strands separated by loops; in this model, Tyr-155 maps to loop 7 while Tyr-188 and Ser-190 map to loop 9. The close proximity of these two loops is also supported by previous results from competition experiments with neutralizing MAbs directed at RRV VP8.


Assuntos
Capsídeo/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Rotavirus/metabolismo , Alanina/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Capsídeo/química , Capsídeo/genética , Proteínas do Capsídeo , Dissulfetos , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Glicoforinas/metabolismo , Glicoforinas/farmacologia , Testes de Hemaglutinação , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
18.
Mol Vis ; 3: 9, 1997 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-9285773

RESUMO

PURPOSE: micro-Crystallin is a major taxon-specific lens protein in some marsupials. Like other taxon-specific crystallins, it probably has another, non-crystallin role. Here we examine the distribution of mu-crystallin among species and its localization in the eye in placental mammals. We also compare its sequence and ligand binding characteristics with those of known enzymes. METHODS: An antibody (Mup1) was raised against a conserved 21 residue peptide of tammar wallaby mu-crystallin. This was used to detect mu-crystallin immunoreactivity in lens extracts of several species and in the tissues of rat and bovine eyes. PCR methods were used to complete the cDNA sequence of human mu-crystallin. The ability of kangaroo mu-crystallin to bind enzymatic cofactors was tested by blue-sepharose chromatography. RESULTS: Using Mup1, abundant mu-crystallin was observed in soluble whole lens extracts of diurnal Australian marsupials. Although abundant micro-crystallin was not detectable in whole lens of nocturnal marsupials, other mammals or a bird, lower levels of immunoreactivity were detectable in lens epithelium, retinal pigment epithelium and, particularly, retina of bovine eye. In rat eye the highest levels of Mup1 reactivity were found in retinal photoreceptors. Sequence comparisons of human and kangaroo mu-crystallin reveal a superfamily relationship with enzymes of glutamate and ornithine metabolism. Co-factor binding studies indicate that mu-crystallin, like related glutamyl-tRNA reductases, binds NADPH. CONCLUSIONS: These results suggest that mu-crystallin is a normal component of retina and other tissues which underwent gene recruitment to gain an additional structural role in the lens during the evolution of diurnal marsupial species. mu-crystallin may be an enzyme, possibly of amino acid metabolism, with particular importance for photoreceptors.


Assuntos
Cristalinas/metabolismo , Cristalino/enzimologia , Marsupiais/metabolismo , Retina/enzimologia , Sequência de Aminoácidos , Aminoácidos/metabolismo , Animais , Anticorpos/análise , Sequência de Bases , Western Blotting , Bovinos , Cristalinas/genética , Cristalinas/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imuno-Histoquímica , Mamíferos , Dados de Sequência Molecular , NADP/metabolismo , Reação em Cadeia da Polimerase , Ratos , Alinhamento de Sequência , Especificidade da Espécie , Cristalinas mu
19.
Rev Med Chil ; 124(6): 715-9, 1996 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-9041729

RESUMO

BACKGROUND: The frequency of Streptococcus pyogenes infections with deep tissue invasion and toxic shock syndrome has increased in the last decade throughout the world. AIM: To compare antimicrobial susceptibility of S. pyogenes strains isolated during 1986 and during 1994-95. MATERIAL AND METHOD: Eighty two S. pyogenes strains isolated in 1986 and 67 strains isolated in 1994-95, were studied. MIC 50 and 90 were determined by and agar dilution method for penicillin, ampicillin, cefazolin, cefuroxime, erythromycin, roxithromycin and miocamycin. RESULTS: Eighty eight strains came from skin of soft tissues, 19 from surgical wounds, 18 from invasive infections, 15 from pharyngeal swabs and 9 from other locations. All strains were susceptible to penicillin, ampicillin, cefazolin, cefuroxime, roxithromycin and miocamycin. Ninety nine percent of strains were susceptible to erythromycin. Strains isolated in 1995-95 had a higher MIC 50 and 90 for erythromycin than those isolated in 1986. CONCLUSIONS: The changes in susceptibility to erythromycin of recently isolated strains could be due to the widespread use of macrolides in Chile.


Assuntos
Ampicilina/farmacologia , Cefalosporinas/farmacologia , Macrolídeos/farmacologia , Penicilinas/farmacologia , Streptococcus pyogenes/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
20.
Appl Environ Microbiol ; 61(11): 3992-7, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8526514

RESUMO

Two genes encoding citrate synthase, a key enzyme in the Krebs cycle, have been found in Rhizobium tropici. One of them is in the bacterial chromosome, while the other is in the symbiotic plasmid. We sequenced the chromosomal gene and found that it is very similar to the previously reported plasmidic gene sequence in its structural region but not in its regulatory region. The chromosomal gene is able to complement an Escherichia coli citrate synthase mutant. In R. tropici, a mutant in the chromosomal citrate synthase gene has a diminished citrate synthase activity (in free-living bacteria), a diminished nodulation capacity, and forms nitrogen-fixing nodules. In contrast, the citrate synthase double mutant forms ineffective nodules devoid of bacteroids and forms less nodules than the single chromosomal mutant. It is inferred that both genes are functional and required during the nodulation process in R. tropici.


Assuntos
Cromossomos Bacterianos/genética , Citrato (si)-Sintase/genética , Genes Bacterianos , Rhizobium/enzimologia , Rhizobium/genética , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA/genética , DNA Bacteriano/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Teste de Complementação Genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fenótipo , Plasmídeos/genética , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Simbiose
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