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A C Alves

Publications and source records attributed to A C Alves.

At least 19 recordsLinked to original sources
PubMed2006

Malaria parasites can develop stable resistance to artemisinin but lack mutations in candidate genes atp6 (encoding the sarcoplasmic and endoplasmic reticulum Ca2+ ATPase), tctp, mdr1, and cg10.

Resistance of Plasmodium falciparum to drugs such as chloroquine and sulfadoxine-pyrimethamine is a major problem in malaria control. Artemisinin (ART) derivatives, particularly in combination with other drugs, are thus increasingly used to treat malaria, reducing the probability that parasites resistant to the components will emerge. Although stable resistance to artemisinin has yet to be reported from laboratory or field studies, its emergence would be disastrous because of the lack of alternative treatments. Here, we report for the first time, to our knowledge, genetically stable and transmissible ART and artesunate (ATN)-resistant malaria parasites. Each of two lines of the rodent malaria parasite Plosmodium chabaudi chabaudi, grown in the presence of increasing concentrations of ART or ATN, showed 15-fold and 6-fold increased resistance to ART and ATN, respectively. Resistance remained stable after cloning, freeze-thawing, after passage in the absence of drug, and transmission through mosquitoes. The nucleotide sequences of the possible genetic modulators of ART resistance (mdr1, cg10, tctp, and atp6) of sensitive and resistant parasites were compared. No mutations in these genes were identified. In addition we investigated whether changes in the copy number of these genes could account for resistance but found that resistant parasites retained the same number of copies as their sensitive progenitors. We believe that this is the first report of a malaria parasite with genetically stable and transmissible resistance to artemisinin or its derivatives.

Amino Acid Sequence↗
PubMed2005

Relationship between angiogenesis and grade of histologic differentiation in endometrial adenocarcinoma.

The objective of the study was to quantify vessels and to relate them to the degree of histologic differentiation in endometrial adenocarcinoma. We studied 35 cases of which ten were G1, 13 G2 and 12 G3 adenocarcinomas. The control group consisted of 11 atrophic and 10 proliferative endometria. From each case two histologic sections were obtained: one for hematoxylin-eosin staining and the other for immunohistochemical study with anti-CD34. Vessel count was performed by morphometric study. Mean vessel count was 15.3 for G1; 19 for G2 and 22.7 for G3 adenocarcinomas; in the control group it was 11.6 for atrophic and 13.2 for proliferative endometria. Slightly differentiated adenocarcinoma presented greater angiogenesis than normal and well-differentiated carcinoma. In contrast, moderately differentiated carcinoma showed greater angiogenicity as related to normal endometrium, but did not differ from other tumoral endometria.

Carcinoma, Endometrioid↗
PubMed2003

Importance of combined-modality therapy for primary bone lymphoma.

Primary bone lymphoma (PBL) is a rare entity and comprises about 5% of all extranodal non-Hodgkin's lymphomas (NHL) and 7% of all primary bone tumors. To date there is no consensus about the optimal treatment for PBL. We retrospectively reviewed all cases of PBL treated at Hospital São Paulo, Brazil, over a 10-year-period (January 1992-January 2002). Medical records of 7 patients with PBL were reviewed and information on age at diagnosis, sex, NHL clinical staging (CS), treatment and response to treatment were retrieved. Five patients (72%) received combined-modality therapy (CMT) and all of them are in complete remission (CR) with a median follow up of 19 months (ranging from 12 to 144 months). We conclude that PBL is a potentially curable malignancy and treatment should be undertaken in a multiprofessional approach, in order to provide the best support which probably has to include chemotherapy, radiotherapy and, for patients with IPI higher than 2, consolidation with stem-cell transplantation.

Adult↗
PubMed2002

Mycoplasma genitalium is not associated with adverse outcomes of pregnancy in Guinea-Bissau.

OBJECTIVE: To evaluate the impact of Mycoplasma genitalium on the outcome of pregnancy. METHODS: Cervical samples from women who had previously participated in a case-control study (designed to assess the impact of syphilis and HIV-2 on the outcome of pregnancy in Guinea-Bissau) were processed using a PCR assay to detect the presence of M genitalium. Controls were women who had delivered a term neonate with a birth weight over 2500 g. Cases were classified into four groups of mothers according to the outcome of pregnancy: stillbirths, spontaneous abortions, premature deliveries, and small for gestational age (SGA) babies. RESULTS: Among the 1014 women included in this study, 6.2% were infected with M genitalium. M genitalium infection was not significantly associated with any of the adverse outcomes of pregnancy studied. Odds ratios (OR) for premature or SGA delivery in the presence of M genitalium infection were 1.37 (95% CI 0.69 to 2.60) and 0.44 (95% CI 0.01 to 2.75), respectively. For abortions and stillbirths, OR were respectively 0.61 (95% CI 0.07 to 2.51) and 1.07 (95% CI 0.42 to 2.42). CONCLUSION: M genitalium appears not to have a deleterious impact on the outcome of pregnancy.

Adolescent↗
PubMed2001

Modulation of eotaxin formation and eosinophil migration by selective inhibitors of phosphodiesterase type 4 isoenzyme.

1. This study was undertaken to investigate the possible contribution of the blockade of eotaxin generation to the anti-eosinophilotactic effect of phosphodiesterase (PDE) type 4 inhibitors. In some experiments, the putative synergistic interaction between PDE type 4 inhibitors and the beta2-agonist salbutamol was also assessed. 2. Sensitized guinea-pigs aerosolized with antigen (5% ovalbumin, OVA) responded with a significant increase in eotaxin and eosinophil levels in the bronchoalveolar lavage fluid (BALF) at 6 h. Eosinophil recruitment was inhibited by both PDE type 4 inhibitors rolipram (5 mg kg(-1), i.p.) and RP 73401 (5 mg kg(-1), i.p.) treatments. In contrast, only rolipram inhibited eotaxin production. 3. Sensitized rats intrapleurally challenged (i.pl.) with antigen (OVA, 12 microg cavity(-1)) showed a marked eosinophil infiltration at 24 h, preceded by eotaxin generation at 6 h. Intravenous administration of a rabbit anti-mouse eotaxin antibody (0.5 mg kg(-1)) significantly reduced allergen-evoked eosinophilia in this model. 4. Local pretreatment with rolipram (40 microg cavity(-1)) or RP 73401 (40 microg cavity(-1)) 1 h before challenge reduced eosinophil accumulation evaluated in the rat pleural effluent, but only the former was active against eotaxin generation. The inhibitors of PDE type 3 (SK&F 94836) and type 5 (zaprinast) failed to alter allergen-evoked eosinophil recruitment in rats. 5. Local injection of beta2-agonist salbutamol (20 microg cavity(-1)) inhibited both eosinophil accumulation and eotaxin production following pleurisy. The former was better inhibited when salbutamol and rolipram were administered in combination. 6. Treatment with rolipram and RP 73401 dose-dependently inhibited eosinophil adhesion and migration in vitro. These effects were clearly potentiated by salbutamol at concentrations that had no effect alone. 7. Our findings indicate that although rolipram and RP 73401 are equally effective in inhibiting allergen-induced eosinophil infiltration only the former prevents eotaxin formation, indicating that PDE 4 inhibitors impair eosinophil accumulation by mechanisms independent of eotaxin production blockade.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2000

Prognostic factors in non-Hodgkin lymphomas.

CONTEXT: In Hodgkin's disease, each clinical or pathologic stage can be related to the extent of the area involved and predicts the next anatomical region at risk for tumor dissemination. OBJECTIVE: To determine the best prognostic factors that could predict survival in non-Hodgkin lymphoma cases. DESIGN: A retrospective study. LOCATION: Department of Hematology and Transfusion Medicine, Universidade Federal de São Paulo - Escola Paulista de Medicina. PARTICIPANTS: 142 patients with non-Hodgkin lymphoma diagnosed between February 1988 and March 1993. MAIN MEASUREMENTS: Histological subset, Sex, Age, Race, B symptoms, Performance status, Stage, Extranodal disease, Bulk disease, Mediastinal disease, CNS involvement, BM infiltration, Level of DHL, Immunophenotype. RESULTS: In the first study (113 patients), the following variables had a worse influence on survival: yellow race (P<0.1); ECOG II, III e IV (P<0.1) and extranodal disease (P<0.1) for high grade lymphomas; constitutional symptoms (P<0.1), ECOG II, III e IV (P<0.1) and involvement of CNS (P<0.1) for intermediate grade and the subtype lymphoplasmocytoid (P=0.0186) for low grade lymphomas. In the second survey (93 patients), when treatment was included, the variables related to NHL survival were: CNS involvement (P<0.1) for high grade lymphomas, constitutional symptoms (P<0.1), ECOG II, III, IV (P=0.0185) and also CNS involvement (P<0.1) for the intermediate group. There were no variables related to the survival for low-grade lymphomas. CONCLUSIONS: The intermediate grade lymphomas were more compatible with data found in the literature, probably because of the larger number of patients. In this specific case, the treatment did not have an influence on the survival.

Female↗
PubMed2000

Heat shock response reduces mortality after severe experimental burns.

The heat shock response has imparted protective effects in animal models of septic shock and endotoxemia. This study has tested the hypothesis that it could be protective in experimental burns. One hundred and fifteen adult male Fischer rats were randomly divided into four groups. Rats in the first group (n = 12) were anesthetized and shaved. In the second group (n = 15) rats were anesthetized and heated in a 45 degrees C water bath. In the third group (n = 44), rats were anesthetized, shaved and submitted to 26-30% body surface third-degree burns using a brass bar. In the fourth group (n = 44), rats were anesthetized, heated and, 1 day after, they were burnt. Mortality rates were measured at 3, 7, 15 and 25 days. Liver and lung samples were collected from all groups for heat-shock protein 70 detection. Heat-shock protein 70 was positive in heated animals. No animals died in the first or second group. Heated and burnt animals showed significantly decreased mortality at days 3 (p < 0.05, Fischer's exact test) and at days 7, 15 and 25 (p < 0.01) after burns, when compared to unheated burnt animals. In conclusion, eliciting the heat-shock response significantly reduced mortality rates in this model of experimental burns.

Animals↗
PubMed2000

Post-transplant lymphoproliferative disorders (PTLD) after renal transplantation: management and evolution of seven cases among 1002 renal transplants in São Paulo, Brazil.

We reported seven cases (0.7%) of PTLD among 1002 renal transplants performed at Renal Transplant Service from Hospital São Paulo-Universidade Federal de São Paulo/Escola Paulista de Medicina, São Paulo, Brazil, between 1976 and 1997. There were three male and four female patients with median age of 37 year-old. According to Ann Arbor staging system there were four localized extra-nodal intermediate-grade NHL, one disseminated low-grade NHL and two polyclonal lymphoid hyperplasia. Four patients received cadaveric, two received related and one received unrelated renal transplant. PTLD occurred after a median latency period of 36 months (ranging from 5 to 84 months). In situ hybridization for EBER1 was performed in five patients and molecular evidence of EBV was found in 3 cases (two DLCL and one lymphoplasmocytoid lymphoma). All patients were treated with immunosuppression withdrawal, four patients received anthracyclin-based chemotherapy for control of localized or systemic clonal disease and three were treated with resection of primary PTLD. Four of seven patients (57%) are in complete remission 11, 20, 25 and 79 months after PTLD onset. One patient lost follow-up and two patients died due to lymphoma relapse, respectively 4 and 10 months after completion of treatment. In conclusion, our experience with this small group of patients showed that: 1) immunosuppression withdrawal is not necessarily associated with loss of renal transplant and can be used as the only treatment for polyclonal PTLD; 2) chemotherapy can simultaneously lead to clonal PTLD remission and periodic immunosuppression, avoiding graft rejection after immunosuppression withdrawal.

Adult↗
PubMed1999

Insertion of the 5' part of BCR within the ABL gene at 9q34 in a Philadelphia-negative chronic myeloid leukemia.

We report a chronic myeloid leukemia patient without evidence of a Philadelphia (Ph) chromosome in whom RT-PCR analysis performed in blast crisis demonstrated the existence of both common b3a2 and b2a2 BCR/ABL fusion transcripts. In situ hybridization studies with BCR- and ABL-specific probes showed location of the BCR/ABL fusion gene on chromosome 9, band q34, instead of at chromosome 22q11, and that it resulted from an insertion of the 5' side of BCR within the ABL gene on chromosome 9. The vast majority of cells showed a BCR/ABL fusion gene on both chromosomes 9, which is equivalent to a double Ph chromosome, thus reinforcing the notion that the critical event in CML is the formation of a functional BCR/ABL fusion gene.

Chromosomes, Human, Pair 9↗
PubMed1999

Clinical management of six cases of low-risk primary tonsillar non-Hodgkin's lymphoma.

CONTEXT: There have been many reports that favor aggressive systemic treatment with chemotherapy and radiotherapy, even for well-localized lymphomas, avoiding the need for tonsillectomy of the normal tonsil. CASE REPORT: We report six cases of primary tonsillar lymphoma with a median patient age of 42 years. There were two lymphoma cases with diffuse large cells, two cases with mixed small and large cells, one with small cells and one indeterminate. They were treated with six cycles of chemotherapy and cervical radiotherapy. All patients achieved durable complete remission. Our data agree with previous reports that suggested that primary tonsillar high-grade B-cell NHL has a good prognosis if aggressively treated.

Adult↗
PubMed1998

[Accumulation of data about adolescence by nurses: period from 1983 to 1996].

In the last ten years adolescence has been object of study of many researchers and considered by National and International Organizations as an age band with priority to actions of promotion, prevention and protection. Many factors contributed to this concern with adolescence, between them, we can emphasize the importance of this populational contingent that represents 30% of world population, besides the questions of precocious pregnancy, AIDS and drugs. As nurse researchers, we are interested in experiencing and characterizing quantitatively and qualitatively the scientific production about adolescence in nursing, using as source of data collection the national specific nursing periodicals. Data obtained in this research show that the adolescence theme is not explored by the nursing staff, and the most important aspects are related to sexuality.

Adolescent↗
PubMed1997

Effect of selective phosphodiesterase inhibitors on the rat eosinophil chemotactic response in vitro.

In the present study, we have performed a comparative analysis of the effect of selective inhibitors of phosphodiesterase (PDE) type III, IV and V on eosinophil chemotaxis triggered by platelet activating factor (PAF) and leukotriene B4 (LTB4) in vitro. The effect of the analogues N6-2'-O-dibutyryladenosine 3':5'cyclic monophosphate (Bt2 cyclic AMP) and N2-2'-O-dibutyrylguanosine 3':5' cyclic monophosphate (Bt2 cyclic GMP) has also been determined. The eosinophils were obtained from the peritoneal cavity of naive Wistar rats and purified in discontinuous Percoll gradients to 85-95% purity. We observed that pre-incubation of eosinophils with the PDE type IV inhibitor rolipram suppressed the chemotactic response triggered by PAF and LTB4' in association with an increase in the intracellular levels of cyclic AMP. In contrast, neither zaprinast (type V inhibitor) nor type III inhibitors milrinone and SK&F 94836 affected the eosinophil migration. Only at the highest concentration tested did the analogue Bt2 cyclic AMP suppress the eosinophil chemotaxis, under conditions where Bt2 cyclic GMP was ineffective. We have concluded that inhibition of PDE IV, but not PDE III or V, was able to block the eosinophil chemotaxis in vitro, suggesting that the suppressive activity of selective PDE IV inhibitors on tissue eosinophil accumulation may, at least, be partially dependent on their ability to directly inhibit the eosinophil migration.

Analysis of Variance↗
PubMed1996

Selective inhibition of phosphodiesterase type IV suppresses the chemotactic responsiveness of rat eosinophils in vitro.

Previous studies demonstrated that the selective inhibition of phosphodiesterase type IV suppresses antigen-induced eosinophil infiltration and also downregulates certain eosinophil functions assessed in vitro. In the current study, we compared the effect of selective inhibitors of phosphodiesterase IV with the effect of phosphodiesterase III and V inhibitors, focusing on eosinophil chemotaxis stimulated by platelet-activating factor (PAF) and leukotriene B4 in a modified Boyden chamber. The effect of beta 2-adrenoceptor agonists and forskolin as well as the analogue N6-2'-O-dibutyryladenosine 3':5'-cyclic monophosphate (Bt2 cyclic AMP) was also determined. For this purpose eosinophils were obtained by lavage of the peritoneal cavity of normal Wistar rats and purified on Percoll gradients to 85-95% purity. Our results showed that PAF and leukotriene B4 (0.001-10 microM) elicited a concentration-dependent increase in eosinophil migration with maximal responses observed at 1 microM and 0.1 microM respectively. Pre-incubation with the type IV phosphodiesterase inhibitor, rolipram (1-100 microM), suppressed the chemotactic response triggered by PAF and leukotriene B4, in association with elevation of eosinophil cyclic AMP, whereas the compounds milrinone and SK&F 94836 (type III selective) as well as zaprinast (type V selective) were ineffective. The beta 2-adrenoceptor agonists salbutamol and salmeterol (1-100 microM) did not alter the intracellular levels of cyclic AMP and also failed to inhibit the eosinophil response. Moreover, incubation of eosinophils with the adenylate cyclase activator forskolin (1-100 microM), while inducing a discrete increase in cyclic AMP, markedly inhibited PAF- and leukotriene B4-induced eosinophil chemotaxis. Eosinophils treated with a combination of individually inactive amounts of forskolin plus rolipram significantly inhibited the eosinophil migration elicited by PAF and leukotriene B4, but did not change cyclic AMP baseline levels. Though only at the highest concentration tested (100 microM), the analogue Bt2 cyclic AMP abolished the eosinophil chemotaxis. Thus we conclude that the direct inhibitory effect of phosphodiesterase IV inhibitors on eosinophil chemotaxis may account for their suppressive activity on tissue eosinophil accumulation following antigen challenge.

Adrenergic beta-Agonists↗
PubMed1996

Local exposure to salbutamol or Bt2 cyclic AMP inhibits pleural exudation and leukocyte influx caused by antigen in rats.

The local effect of salbutamol and N6,2'-O-dibutyryl adenosine 3':5'-cyclic monophosphate (Bt2 cyclic AMP) on the rat pleural inflammation caused by allergen was investigated. Antigen (ovalbumin, 12 micrograms/cavity) intrathoracically administered to immunized rats led to a marked pleural protein extravasation and leukocyte infiltration, as attested by the quantification of protein and enumeration of leukocytes recovered from the pleural cavity. Salbutamol (10-40 micrograms/cavity) and the cell-permeable cyclic AMP analogue, Bt2 cyclic AMP (20-160 micrograms/cavity), injected 1 h and 5 min before the antigen, respectively, inhibited the exudation occurring within 30 min, and neutrophil and eosinophil accumulation occurring 4 and 24 h, respectively. The late eosinophilia was also markedly attenuated by salbutamol administered 10 min post-challenge, when mast cells had already been degranulated. Pretreatment with the beta-adrenoceptor antagonist propranolol (1 mg/kg, i.v.) failed to modify the inhibitory effect of Bt2 cyclic AMP, but abolished the blockade caused by salbutamol of leukocyte infiltration under conditions where the salbutamol anti-exudatory activity was impaired to about 80%. In another set of experiments, salbutamol (20 and 40 micrograms/cavity) markedly inhibited the exudation caused by histamine and 5-hydroxytryptamine (5-HT) which, though to a lesser extent, was also sensitive to Bt2 cyclic AMP (80 micrograms/cavity). As observed with allergic pleurisy, propranolol impaired the inhibition by salbutamol of histamine- and 5-HT-induced exudation, whereas the Bt2 cyclic AMP inhibition was not affected. We conclude that salbutamol and Bt2 cyclic AMP share the ability to inhibit pleural exudation and leukocyte recruitment caused by allergen in immunized rats, suggesting that the anti-inflammatory effect of salbutamol may be mediated by a cyclic AMP signaling pathway, probably via beta 2-adrenoceptor activation.

Adrenergic beta-Agonists↗
PubMed1996

Alloxan diabetes reduces pleural mast cell numbers and the subsequent eosinophil influx induced by allergen in sensitized rats.

Alloxan damages insulin-producing cells and has been used as an inducer of experimental diabetes in several animal species. In this study, administration of alloxan (40 mg/kg, i.v.) to rats was followed by a selective and time-dependent reduction in the number of pleural mast cells (50 +/- 2.2%, p < 0.01; mean +/- SEM), while mononuclear cell and eosinophil counts were not altered. As compared to naive rats, the reduction in mast cell numbers was first noted 48 h following alloxan administration and remained unaltered for at least 60 days. It is noteworthy, that the depletion in the mast cell population was not accompanied by alterations in the total amount of histamine stored per cell. Sensitized rats turned diabetic by alloxan treatment performed 72 h before challenge showed a less pronounced antigen-induced mast cell degranulation compared to nondiabetic rats. Moreover, rats injected with alloxan 72 and 48 but not 24 h before challenge, reacted to allergenic challenge with 50% reduction in the number of eosinophils recruited to the pleural cavity within 24 h. We found that the less pronounced eosinophil accumulation did not relate to an intrinsic cell locomotor abnormality since eosinophils from diabetic rats presented similar chemotactic responses to LTB4 and PAF in vitro as compared to matching controls. Insulin (3 IU/rat) restored basal levels of mast cells and reversed the subsequent inhibition of allergen-induced pleural eosinophilia, suggesting a causative relationship between these phenomena. Treatment with insulin also significantly increased the number of mast cells in the pleural cavity of naive rats (from 637 +/- 57 to 978 +/- 79 x 10(3) cells/cavity, p < 0.001). Consistently, previous depletion of mast cells by means of local treatment with compound 48/80 significantly reduced the antigen-induced eosinophil recruitment in sensitized animals. We conclude that the reduction in the pleural mast cell population noted in alloxan-treated rats could be directly implicated in the diminished pleural eosinophil influx following allergen challenge. This hyporesponsiveness is independent of an intrinsic abnormality of cell chemotaxis, but can be imitated by local mast cell depletion.

Alloxan↗
PubMed1995

Interruption of breast feeding caused by the presence of neonatal teeth.

The authors report the case of a 6-month old girl treated at the Pediatric Dentistry Clinic at the School of Dentistry of the Federal University of Rio de Janeiro. The patient's breast feeding was interrupted prematurely due to the presence of neonatal teeth. The authors have included a brief review of previous reports of this pathology.

Breast Feeding↗