Alelos de antígeno leucocitario humano (HLA) clase I en pacientes con cáncer de mama y cuello uterino / HLA alleles in patients with breast and cervix neoplasms

Numerosos autores han informado sobre la influencia del polimorfismo del complejo principal de histocompatibilidad en una correcta o defectuosa presentación antígena, y su relación con la posible susceptibilidad o resistencia a desarrollar enfermedades neoplásicas. Objetivos: 1) Determinación de variantes alélicas del HLA clase I, y su posible vinculación a la susceptibilidad o resistencia en el desarrollo de tumores mamarios y de cérvix uterino. 2) Comparar nuestros resultados con los reportados por otros autores. Material y método: evaluamos 78 pacientes (ptes.), 46 con cáncer de mama, 32 con cáncer de cérvix y 94 testigos, los cuales fueron tipificados para los locus A y B del HLA clase I, utilizando amplificación genérica por PCR, y analizados por hibridación con sondas de oligonucleótidos alelo específica...(AU)

Alelos de antígeno leucocitario humano (HLA) clase I en pacientes con cáncer de mama y cuello uterino / HLA alleles in patients with breast and cervix neoplasms

Numerosos autores han informado sobre la influencia del polimorfismo del complejo principal de histocompatibilidad en una correcta o defectuosa presentación antígena, y su relación con la posible susceptibilidad o resistencia a desarrollar enfermedades neoplásicas. Objetivos: 1) Determinación de variantes alélicas del HLA clase I, y su posible vinculación a la susceptibilidad o resistencia en el desarrollo de tumores mamarios y de cérvix uterino. 2) Comparar nuestros resultados con los reportados por otros autores. Material y método: evaluamos 78 pacientes (ptes.), 46 con cáncer de mama, 32 con cáncer de cérvix y 94 testigos, los cuales fueron tipificados para los locus A y B del HLA clase I, utilizando amplificación genérica por PCR, y analizados por hibridación con sondas de oligonucleótidos alelo específica...

Hepatitis A en la infancia. La punta del iceberg infectológico? / Viral Hepatitis A in childhood. The tip of an infections disease iceberg

The objectives of this study were to analyze the seroepidemiologic prevalence of Hepatitis A Virus (HAV) in children of the city of Resistencia by means of specific antibody detection, relate these data with the socio-sanitary conditions, and discuss vaccine strategies. Two hundred and eighty eight children between 2 and 14 years of age, with a mean of 6.6 years, of both sexes and with no patent liver disease were studied. Blood samples were taken, and the presence of total anti-HAV antibodies was determined. A prevalence of 83.3% was found with no significant differences between sexes. When age groups were compared, antibodies were found in 57.3% of children between 2 and 4 years of age, 90.8% in the 5 to 9 group, and 96.6% in the 10 to 14 group. It was seen that the precarious system of excreta elimination, the lack of potable water in the dwellings, and the absence of sanitary devices, were statistically associated with the high prevalence of HAV infection. In view of the high endemicity found in the first years of life, and considering this disease as a marker of other pathologies with a similar pattern of dissemination, these data may represent the tip of an iceberg holding a broad base of accompanying infections with a high impact in the health of the population. A simultaneous approach towards anti HAV vaccination in young children, and the political decision of improving socio-sanitary conditions and decreasing poverty indexes, should be promptly implemented (AU)

Hepatitis A en la infancia. La punta del iceberg infectológico? / Viral Hepatitis A in childhood. The tip of an infections disease iceberg

The objectives of this study were to analyze the seroepidemiologic prevalence of Hepatitis A Virus (HAV) in children of the city of Resistencia by means of specific antibody detection, relate these data with the socio-sanitary conditions, and discuss vaccine strategies. Two hundred and eighty eight children between 2 and 14 years of age, with a mean of 6.6 years, of both sexes and with no patent liver disease were studied. Blood samples were taken, and the presence of total anti-HAV antibodies was determined. A prevalence of 83.3% was found with no significant differences between sexes. When age groups were compared, antibodies were found in 57.3% of children between 2 and 4 years of age, 90.8% in the 5 to 9 group, and 96.6% in the 10 to 14 group. It was seen that the precarious system of excreta elimination, the lack of potable water in the dwellings, and the absence of sanitary devices, were statistically associated with the high prevalence of HAV infection. In view of the high endemicity found in the first years of life, and considering this disease as a marker of other pathologies with a similar pattern of dissemination, these data may represent the tip of an iceberg holding a broad base of accompanying infections with a high impact in the health of the population. A simultaneous approach towards anti HAV vaccination in young children, and the political decision of improving socio-sanitary conditions and decreasing poverty indexes, should be promptly implemented

[Hepatitis A in childhood. The tip of an infectious disease iceberg]. / Hepatitis A en la infancia. La punta del iceberg infectológico?

The objectives of this study were to analyze the seroepidemiologic prevalence of Hepatitis A Virus (HAV) in children of the city of Resistencia by means of specific antibody detection, relate these data with the socio-sanitary conditions, and discuss vaccine strategies. Two hundred and eighty eight children between 2 and 14 years of age, with a mean of 6.6 years, of both sexes and with no patent liver disease were studied. Blood samples were taken, and the presence of total anti-HAV antibodies was determined. A prevalence of 83.3% was found with no significant differences between sexes. When age groups were compared, antibodies were found in 57.3% of children between 2 and 4 years of age, 90.8% in the 5 to 9 group, and 96.6% in the 10 to 14 group. It was seen that the precarious system of excreta elimination, the lack of potable water in the dwellings, and the absence of sanitary devices, were statistically associated with the high prevalence of HAV infection. In view of the high endemicity found in the first years of life, and considering this disease as a marker of other pathologies with a similar pattern of dissemination, these data may represent the tip of an iceberg holding a broad base of accompanying infections with a high impact in the health of the population. A simultaneous approach towards anti HAV vaccination in young children, and the political decision of improving socio-sanitary conditions and decreasing poverty indexes, should be promptly implemented.

Hepatitis A en la infancia. La punta del iceberg infectológico? / [Hepatitis A in childhood. The tip of an infectious disease iceberg]

The objectives of this study were to analyze the seroepidemiologic prevalence of Hepatitis A Virus (HAV) in children of the city of Resistencia by means of specific antibody detection, relate these data with the socio-sanitary conditions, and discuss vaccine strategies. Two hundred and eighty eight children between 2 and 14 years of age, with a mean of 6.6 years, of both sexes and with no patent liver disease were studied. Blood samples were taken, and the presence of total anti-HAV antibodies was determined. A prevalence of 83.3

was found with no significant differences between sexes. When age groups were compared, antibodies were found in 57.3

of children between 2 and 4 years of age, 90.8

in the 5 to 9 group, and 96.6

in the 10 to 14 group. It was seen that the precarious system of excreta elimination, the lack of potable water in the dwellings, and the absence of sanitary devices, were statistically associated with the high prevalence of HAV infection. In view of the high endemicity found in the first years of life, and considering this disease as a marker of other pathologies with a similar pattern of dissemination, these data may represent the tip of an iceberg holding a broad base of accompanying infections with a high impact in the health of the population. A simultaneous approach towards anti HAV vaccination in young children, and the political decision of improving socio-sanitary conditions and decreasing poverty indexes, should be promptly implemented.

HLA class I alleles associated with susceptibility or resistance to human immunodeficiency virus type 1 infection among a population in Chaco Province, Argentina.

Host genetic factors, such as HLA alleles, are important in human immunodeficiency virus (HIV) infection and its progression to AIDS. HLA class I gene products are involved in peptide presentation, and each allele is responsible for presenting a different set of peptides to cytotoxic T lymphocytes. The increase or decrease in the frequency of certain alleles in HIV-1-positive versus control subjects would suggest that alleles play a role in susceptibility to or protection against this viral infection. In the present study, 56 HIV-1-positive patients in Chaco Province, Argentina, were typed for the HLA-A and HLA-B loci, using polymerase chain reaction and sequence-specific oligonucleotide probes. The frequency of alleles A*24, B*18, and B*39 was increased in HIV-1-positive subjects, suggesting that these alleles play a role in susceptibility to HIV-1 infection. Alleles B*44 and B*55 were not found in HIV-1-positive subjects, suggesting that they have a protective effect against the disease. The P values of the alleles B*39 and B*44 were statistically significant (P<.05).

[Frequency of the mutated allele of CCR-5 receptor in HIV-1 positive and negative individuals in the Province of Chaco]. / Frecuencia del alelo mutado del receptor CCR-5 en individuos HIV-1 positivos y negativos en la provincia del Chaco.

The importance of chemokine receptors in the pathophysiology of HIV infection became apparent when it was demonstrated that persons at high risk for HIV-1 infection remain uninfected when they carry a polymorphic variant of CCR5. In individuals who are homozygous for the 32 base-pair deletion in the CCR5 gene, a functional protein cannot be synthesized and such persons are not found in HIV-1 positive cohorts. Furthermore, in individuals heterozygous for that mutation, there is an association with slow disease progression. The mutant allele of CCR-5 is present at high frequency in the Caucasian population, but is absent in the Japanese and black populations. The aim of this study was to assess the frequency of the truncated allele of CCR-5 gene in the cohort of HIV infected and non-infected subjects in the Province of Chaco, Argentina (with Guaraní and Hispanic genetic background). A total of 118 unrelated seronegative healthy blood donors and 80 seropositive HIV-1 subjects were studied. A portion of CCR-5 gene from genomic DNA was amplified by PCR and analyzed on a 3% agarose gel. The frequency of the delta CCR-5 allele was 2.5% for homozygous and 15.3% for heterozygous seronegative subjects, similar to that reported in the Caucasian population; the homozygous CCR-5 allele was absent in HIV-1 positive patients and the frequency of heterozygous was 2.5%, significantly lower than reported in the Caucasian population.

Frecuencia del alelo mutado del receptor CCR-5 en individuos HIV-1 positivos y negativos en la provincia del Chaco. / [Frequency of the mutated allele of CCR-5 receptor in HIV-1 positive and negative individuals in the Province of Chaco]

The importance of chemokine receptors in the pathophysiology of HIV infection became apparent when it was demonstrated that persons at high risk for HIV-1 infection remain uninfected when they carry a polymorphic variant of CCR5. In individuals who are homozygous for the 32 base-pair deletion in the CCR5 gene, a functional protein cannot be synthesized and such persons are not found in HIV-1 positive cohorts. Furthermore, in individuals heterozygous for that mutation, there is an association with slow disease progression. The mutant allele of CCR-5 is present at high frequency in the Caucasian population, but is absent in the Japanese and black populations. The aim of this study was to assess the frequency of the truncated allele of CCR-5 gene in the cohort of HIV infected and non-infected subjects in the Province of Chaco, Argentina (with Guaraní and Hispanic genetic background). A total of 118 unrelated seronegative healthy blood donors and 80 seropositive HIV-1 subjects were studied. A portion of CCR-5 gene from genomic DNA was amplified by PCR and analyzed on a 3

agarose gel. The frequency of the delta CCR-5 allele was 2.5

for homozygous and 15.3

for heterozygous seronegative subjects, similar to that reported in the Caucasian population; the homozygous CCR-5 allele was absent in HIV-1 positive patients and the frequency of heterozygous was 2.5

, significantly lower than reported in the Caucasian population.

[Anti-neutrophil cytoplasmic antibodies (ANCA) in patients with symptomatic and asymptomatic HIV infection]. / Anticuerpos anticitoplasma de neutrófilos (ANCA) en pacientes infectados por HIV sintomáticos y asintomáticos.

The cytopathic effect of HIV on CD4 T cells, as well as the active autoimmune mechanism occurring during infection, have been documented. Of the cytokines involved in the pathogenesis of AIDS, the main one produced by the monocyte-macrophage series is tumor necrosis factor alfa (TNF alpha). This cytokine induces antigens such as proteinase 3 (Pr 3) or mieloperoxidase (MPO). Anti-neutrophil cytoplasmic antibodies (ANCA) are directed against this type of PMN antigens. In the present paper, the role of anti-neutrophil cytoplasmic antibodies (ANCA) in HIV infected patients as responsible for autoimmune phenomena in relation to opportunistic infections, was studied. A total of 88 serum samples belonging to 49 asymptomatic and 39 symptomatic HIV infected patients were tested for ANCA by an indirect immunofluorescence (IIF) test over a neutrophil substrate. ANCA were detected in 53.8% of symptomatic patients as compared to 4.1% in asymptomatic cases (p < 0.0001). A 95.9% correlation was observed between ANCA-positive samples and pulmonary infection (n = 20). In those ANCA (+) samples 95.9% correlation was found with pulmonary infection (n = 20). Pulmonary infection due to Mycobacterium tuberculosis is a frequent finding in HIV infected patients from Northeastern Argentina. When the presence of ANCA in TB(+) HIV(+) and TB(+) HIV(-) patients was studied, it was seen that positive-ANCA significantly correlated with the first group (p < 0.001). The presence of ANCA was not related to viral infections, toxoplasmosis, neurological features of AIDS, vasculitis or malignant diseases. ANCA during pulmonary infection, mostly caused by TB, as well as PMN infiltration in pulmonary parenchyma, and the deregulated immune reaction elicited by HIV, may contribute to the onset of autoimmune phenomena. The presence of human T lymphocytes reactive to heat stress proteins (Hsp), an important target of immune response against certain intracellular auto-antigens such as MPO from PMN, added to the mechanism of molecular mimicry, could explain the association of ANCA and TB in patients with severe alterations of their immune response. According to these results, the limited presence of ANCA in asymptomatic patients HIV(+) and in HIV(-) with pulmonar TB, could indicate that the virus may not be responsible for the induction of these antibodies.

Detection of an atypical rotavirus associated with diarrhoea in Chaco, Argentina.

Recently some unusual human and animal rotaviruses have been described which, although indistinguishable from standard rotaviruses by electron microscopy (EM), fail to react with antibody directed against the rotavirus group antigen. The genome of these viruses is composed of 11 double-stranded (ds) RNA segments; these RNA segments display different patterns when analysed by means of polyacrylamide gel electrophoresis (PAGE). The electrophoretic profile of the ds RNA segments of those human, antigenically different, viruses reported up to now appear to fit into two different patterns. Faecal samples from children with diarrhoea from different geographical areas of Argentina were evaluated for the presence of rotaviruses, using EM, ELISA and PAGE. During this survey a rotavirus-like agent was detected in the faeces of a child with diarrhoea from Chaco province, North-East Argentine. The pattern of the ds RNA segment of this virus on PAGE analysis appeared to be related to one of the atypical rotaviruses. This is the first description of such a virus strain in Argentina.