A current review of pathogenicity determinants of Streptococcus sp.

The genus Streptococcus comprises important pathogens, many of them are part of the human or animal microbiota. Advances in molecular genetics, taxonomic approaches and phylogenomic studies have led to the establishment of at least 100 species that have a severe impact on human health and are responsible for substantial economic losses to agriculture. The infectivity of the pathogens is linked to cell-surface components and/or secreted virulence factors. Bacteria have evolved sophisticated and multifaceted adaptation strategies to the host environment, including biofilm formation, survival within professional phagocytes, escape the host immune response, amongst others. This review focuses on virulence mechanism and zoonotic potential of Streptococcus species from pyogenic (S. agalactiae, S. pyogenes) and mitis groups (S. pneumoniae).

Steatosis caused by experimental periodontitis is reversible after removal of ligature in rats.

BACKGROUND AND OBJECTIVE: Periodontitis may promote harmful systemic effects such as changes in hepatic tissues. The purpose of this study was to investigate whether the steatosis and oxidative stress caused by experimental periodontitis are reversible in the liver. MATERIAL AND METHODS: Twenty-four rats were divided into three groups: control, periodontitis and P20-20 (20 days with experimental periodontitis and 20 days without experimental periodontitis, to verify the reversibility of hepatic injuries). The following parameters were assessed: gingival bleeding index, probing pocket depth, myeloperoxidase activity, alveolar bone loss for periodontal tissues; liver weights, histopathological scores for steatosis, inflammation and necrosis in liver; glutathione, malondialdehyde, total cholesterol and triglyceride concentrations in hepatic tissues; and blood levels of aspartate aminotransferase, alanine aminotransferase, albumin, gamma-glutaryl transferase, total cholesterol and random glucose. RESULTS: Gingival bleeding index, probing pocket depth, myeloperoxidase and alveolar bone loss parameters demonstrated the development of periodontitis. There was a significant reduction in the steatosis score of animals from the P20-20 group when compared with the periodontitis group. P20-20 group presented significantly higher glutathione (11 times) and lower malondialdehyde (nearly 23%), total cholesterol (both in blood and hepatic tissue) and triglyceride concentrations compared with the periodontitis group. For levels of aspartate aminotransferase, alanine aminotransferase, albumin, gamma-glutaryl transferase and random glucose, a significant difference between the groups was not observed. CONCLUSION: Our results demonstrate that the microvesicular steatosis caused by periodontitis in rats is reversible after removal of the ligature, which is associated with the increase in oxidative stress and lipid peroxidation in the liver.

Perceived fatigability and metabolic and energetic responses to 6-minute walk test in older women.

OBJECTIVE: To determine the relationship between perceived fatigability and oxygen consumption, carbon dioxide production, respiratory exchange ratio and the energy cost of walking in older women. DESIGN: Observational, cross-sectional study. PARTICIPANTS: Forty-eight community-dwelling older women were recruited from senior centres in Natal, Rio Grande do Norte, Brazil. MAIN OUTCOME MEASURES: Participants were evaluated in two different sessions. In the first session, sociodemographic and clinical factors were assessed and accelerometers were delivered. In the second session, the 6-minute walking test (6MWT) was performed and expired gases were analysed. Self-reported levels of fatigue were evaluated on a numerical scale from 1 ('extremely energetic') to 7 ('extremely tired'). Severity scores for perceived and performance fatigability were calculated as the ratio of change in performance and fatigue, respectively, with walking distance. The O2 cost of walking was based on the oxygen consumption rate and the 6MWT walking speed. RESULTS: No correlation was found between the severity of perceived fatigability and metabolic measures. However, the severity of perceived fatigability was significantly correlated with greater O2 cost (r=0.579, P<0.01), physical activity (r=-0.654, P<0.01), walking distance (r=-0.712, P<0.01) and severity of performance fatigability (r=0.690, P<0.01). CONCLUSION: Perceived fatigability was not directly associated with metabolic measures; however, greater severity of perceived fatigability was associated with an increase in the O2 cost of walking. Important relationships were also found between greater severity of perceived fatigability and poor functional fitness, high level of energy expenditure and lower level of physical activity.

Frequency of SNP -336A/G in the promoter region of CD209 in a population from northeastern Brazil.

Dendritic cells (DCs) mediate the initiation of the immune response against a variety of pathogens. The DC-SIGN receptor is encoded by the gene CD209 and is expressed on the surface of DCs. It binds to mannose-rich carbohydrates and enables the recognition of bacteria, fungi, parasites, and viruses. SNP -336A/G in the promoter region of CD209 influences the expression of the DC-SIGN receptor. Several studies have associated this SNP with an increased susceptibility to infectious diseases and the development of more severe forms of disease. Therefore, the aim of this study was to determine the prevalence of SNP -336A/G in a population from northeastern Brazil. We analyzed 181 individuals from the general population of Parnaíba, Piauí, Brazil, of which 37% were men and 63% were women. SNP -336A/G was detected by polymerase chain reaction and treatment with the restriction enzyme MscI and visualized by electrophoresis on an 8% polyacrylamide gel stained with silver nitrate. Of the individuals analyzed, 116 (64.1%) were homozygous AA, 57 (31.5%) were heterozygous (AG), and 8 (4.4%) were homozygous GG. The allele frequency of -336G was 20.2%. Genotype frequencies were in Hardy-Weinberg equilibrium. To the best of our knowledge, this is the first report to describe the frequency of the CD209 SNP -336A/G in a population in the State of Piauí. Further studies are needed to determine the relationship between this SNP and the vulnerability of this population to major infectious diseases.

Emergence of azole-resistant Candida albicans in small ruminants.

Small ruminant production is a common agricultural activity worldwide. However, studies on the fungal microbiota of these animals are scarce. Therefore, this study aimed at isolating yeasts from goats and sheep and evaluating the antifungal susceptibility of the recovered Candida albicans. A total of 120 animals from farms in Ceará State, Brazil, were assessed in this study. The samples were collected from nasal, oral and rectal cavities with sterile swabs. Candida spp., Trichosporon spp. and Rhodotorula spp. were isolated from small ruminants. Resistance to three azole drugs was observed in C. albicans. In summary, Candida spp. were predominantly observed as part of the microbiota of the nasal, oral and rectal cavities of small ruminants, including azole-resistant strains of C. albicans.

A novel and efficient and low-cost methodology for purification of Macrotyloma axillare (Leguminosae) seed lectin.

The N-acetyl-galactosamine specific lectin from Macrotyloma axillare seeds (LMA) was purified by precipitation and ion exchange chromatography. The LMA 0.2 mol L(-1) fraction showed hemagglutinating activity on erythrocytes A1. The results for molecular mass determinations were about 28 kDa. The LMA pH-dependent assays showed best hemagglutinating activity at pH 6.0-8.0; being decreased at acidic/alkaline conditions and by EDTA treatment. LMA is a tetramer at pH 8.2 and a dimer at pH 4.0. Human erythrocytes from ABO system confirmed the A1 specificity for LMA. This new methodology is useful and easy, with low costs, for lectin purification in large amounts.

Refractory chronic GVHD emerging after splenectomy in a marrow transplant recipient with accelerated phase CML.

We report a 39-year-old female patient who underwent HLA-identical sibling allogeneic BMT for CML in accelerated phase. Severe pancytopenia refractory to G-CSF associated with progressive splenomegaly and RBC/platelet transfusion dependency were present from day +60 after BMT. MRD assessed by FISH and RT-PCR multiplex for BCR-ABL rearrangement was negative, and complete chimerism was documented by VNTR on days +100, +180, +360 and 2 years after BMT. Splenectomy was performed on day +225 and pancytopenia resolved but chronic extensive graft-versus-host disease developed, with hepatic cholestasis, diffuse scleroderma and sicca-like syndrome. She was sequentially and progressively treated with different immunosuppressive therapy combinations with no clear benefit. On day +940, she presented with infection over the previously present ulcers on both limbs, which culminated in septic shock and death on day +1041. We conclude that, although splenectomy may reverse poor graft function after allogeneic BMT, hyposplenism may trigger or worsen chronic extensive GVHD leading to increased morbidity and mortality.

Prognosis related to staging systems for chronic lymphocytic leukemia.

CONTEXT: Chronic lymphocytic leukemia (CLL) is a clonal lymphoproliferative disorder, characterized by B lymphocytic proliferation. CLL is the most frequent adult leukemia in Western countries, accounting for 25 to 30% of all white leukemic patients. OBJECTIVE: To evaluate clinical and staging characteristics in prognosis of chronic lymphocytic leukemia. DESIGN: Evaluation of clinical-staging data. SETTING: Universidade Federal de São Paulo - Escola Paulista de Medicina / Universidade de Alfenas. SAMPLE: 73 patients diagnosed from 1977 to 1994. MAIN MEASUREMENTS: Sex, ethnic origin, age, lymphadenopathy, splenomegaly, hepatomegaly, three or more areas of lymphoid enlargement, hemoglobin (g/dl), lymphocytes/mm3, Platelets/mm3 RESULTS: Mean survival of patients was 76 months, median age was 65 years, ranging from 33 to 87. Forty-four patients (60.3%) were male and 29 (39.7%) female. CONCLUSION: The Binet system determined a better prognosis than Rai.

[Transfusion-associated graft-versus-host disease guideline on gamma irradiation of blood components]. / Doença do enxerto contra hospedeiro pós-transfusional-guia para irradiação gama de hemocomponentes.

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare and usually fatal syndrome. Clinical manifestations are fever, maculopapular skin rash, nausea, vomiting, diarrhea, hepatitis and pancytopenia owing to bone marrow hypoplasia. It can occur in recipients with severe immunosuppression and in immunocompetent recipients after transfusion of cellular components from HLA homozygous donor to recipients heterozygous for that HLA haplotype. The diagnosis is made by clinical manifestation and skin biopsy. Antithymocyte globulin and high dose systemic corticosteroids are both the most used therapy. The back of knowledge about this syndrome, the rapid evolution and the absence of treatment response are related to patients bad evolution. Gamma irradiation of blood products has been the mainstay of TA-GVHD prevention. Dose of 2500 cGy is required to completely inactivate T cells. Irradiation damage red cells membrane and the red celis units can not be storage for long time after irradiation. High potassium levels is the mainly change in red cells units. White cell-reduction filters do not prevent TA-GVHD and gamma irradiation does not prevent alloimmunization or blood reactions. Only cellular components like whole blood, red cells, platelets and granulocytes need be irradiated. Ali blood components should be irradiated to: first or second-degree relatives, patients need HLA-matched platelets, recipients of allogeneic or autologous bone marrow transplantation, patients with Hodgkin's disease, patients treated with purine analogue drugs, intrauterine transfusion, pre-term infants and when congenítal immunodeficiency states is suspected. It is recommended irrradiated blood to patients with neoplastic disease when they receive intensive chemotherapy.

Granulocytic sarcoma presented as a reactivation of chronic myeloid leukemia after allogenic marrow transplantation.

The authors report the case of a chronic myeloid leukemia (CML) patient submitted to allogenic bone marrow transplantation, who had probably never entered complete remission. The disease was reactivated as a granulocytic sarcoma, next to a platinum plate installed to correct a tibia fracture 11 years earlier. Its final event was a myeloid Ph1 + blastic crisis that was unsuccessfully treated with high doses of sc interferon and citarabine.

Megaesophagus in rats.

The objective of this study was to determine whether myenteric denervation of the abdominal esophagus using benzalkonium chloride (BAC) leads to esophageal achalasia with changes of the muscle propria and epithelial cell proliferation. The treatment led to megaesophagus 3 months after BAC application. Denervation of the esophagus induced muscle hypertrophy and increased epithelial cell proliferation. The imbalance of the neurotransmitters may play a role in these morphokinetic changes.

[Rethinking the question of the favelas]. / Repensando a questao das favelas.

"This article intends to analyze some aspects of the evolution of Rio de Janeiro [Brazil]'s squatter settlements over the last decades with emphasis on: the improvement of its residential conditions, the growing diversification of its socio-economic activities and the consequent valorization of its space." (summary in ENG)