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Biomedical subjects

C Marques

Publications and source records attributed to C Marques.

At least 19 recordsLinked to original sources

A qualitative assessment of long distance truck drivers' vulnerability to HIV/AIDS in Itajaí, southern Brazil.

Itajaí is the largest port in southern Brazil and has one of the nation's highest AIDS incidence rates. Since over 400 truck drivers enter the city daily, they may play a key role in the HIV/AIDS epidemic due to transactions with commercial sex workers (CSWs) and/or substance use. We conducted a rapid assessment to establish the context of HIV vulnerability among truckers and CSWs in Itajaí. Forty three in-depth interviews and eight focus groups were conducted with truckers and CSWs. Two truck-driving routes involving brothels, meeting places and drug-use locations were mapped and field observations were collected. Tapes and field notes were transcribed and analyzed for emerging themes. Truck drivers typically had unprotected sex with several partners, including CSWs and truckstop employees. Both truckers and CSWs had low perceived HIV risk in spite of being engaged in high-risk sex behaviors. Use of alcohol and amphetamine-like drugs was frequent among truckers and appeared to influence unsafe sex practices. Knowledge about amphetamine-related risks was low, as was access to health services and HIV/AIDS behavioral interventions. Interventions, targeting truckers, CSWs and truckstop employees, are needed that traverse cities, states and borders and take into account seasonality, spatial context and workplace conditions.

Alcohol Drinking↗

Leishmania infantum: soluble proteins released by the parasite exert differential effects on host immune response.

The objective of this study was to analyse the modulatory effect of proteins released by cultured Leishmania infantum promastigotes on the cellular immune response of infected susceptible (BALB/c) and more resistant (C57BL/6) mice strains after 30 and 45 days of infection. One month after parasite inoculation, L. infantum released protein fractions (High, Inter, and Low according to molecular weight) stimulated C57BL/6 mice spleen cells to proliferate and to express cytokines. Following the decrease of parasite load only the Low protein fraction induced a considerable release of IL-4. In BALB/c mice, specific immune response to protein fractions was only observed at the higher parasitic level, with the fraction Inter promoting the production of IL-4 and fractions High and Low inducing high levels of IL-12. These results point out to a role of these proteins fractions in the modulation of host immunity, that depending on the host genetic background and parasite magnitude, seem to be critical in the control of parasite replication levels, thus avoiding premature host death.

Animals↗

Mitochondrial dysfunction in autism spectrum disorders: a population-based study.

A minority of cases of autism has been associated with several different organic conditions, including bioenergetic metabolism deficiency. In a population-based study, we screened associated medical conditions in a group of 120 children with autism (current age range 11y 5mo to 14y 4mo, mean age 12y 11mo [SD 9.6mo], male:female ratio 2.9:1). Children were diagnosed using Diagnostic and Statistical Manual of Mental Disorders criteria, the Autism Diagnostic Interview--Revised, and the Childhood Autism Rating Scale; 76% were diagnosed with typical autism and 24% with atypical autism. Cognitive functional level was assessed with the Griffiths scale and the Wechsler Intelligence Scale for Children and was in the normal range in 17%. Epilepsy was present in 19 patients. Plasma lactate levels were measured in 69 patients, and in 14 we found hyperlactacidemia. Five of 11 patients studied were classified with definite mitochondrial respiratory chain disorder, suggesting that this might be one of the most common disorders associated with autism (5 of 69; 7.2%) and warranting further investigation.

Adolescent↗

Tempol, an intracelullar free radical scavenger, reduces liver injury in hepatic ischemia-reperfusion in the rat.

Liver ischemia is of clinical interest because of its role in liver failure and also hepatic graft rejection. The generation of reactive oxygen species contributes to the injury that follows ischemia-reperfusion. One therapy utilizes the administration of antioxidants; however, only limited experience suggests a potential benefit of systemic administration of these compounds. To overcome the limitations of these compounds, small molecules with improved cell membrane permeability characteristics and higher potency, such as tempol, are being tested in vivo. Tempol, a membrane-permeable radical scavenger, interferes with the formation or the effects of many radicals, including superoxide anions, hydroxyl radicals, and peroxynitrite. The aim of this study was to investigate the effects of tempol in an in vivo rat model of liver ischemia-reperfusion injury. Male Wistar rats were pretreated with tempol (30 mg/kg, i.v.) 5 minutes prior to liver ischemia (for 30 minutes) and reperfusion (for 2 hours). The liver injury was assessed by measuring serum levels of transaminases, lactate dehydrogenase, and gamma-glutamyl transferase. Tempol significantly mitigated the increase in transaminases, lactate dehydrogenase, and gamma-glutamyl transferase following liver ischemia-reperfusion, suggesting an improvement in liver function and resistance to injury.

Animals↗

Variants of the serotonin transporter gene (SLC6A4) significantly contribute to hyperserotonemia in autism.

The role of the serotonin system in the etiology and pathogenesis of autism spectrum disorders (ASD) is not clearly defined. High levels of platelet serotonin (5-HT) have been consistently found in a proportion of patients, and it is known that specific 5-HT transporter gene (SLC6A4) variants modulate transporter reuptake function, therefore possibly influencing the occurrence of hyperserotonemia in a subset of autistic patients. We have examined the association of platelet serotonin levels with two SLC6A4 polymorphisms, 5-HTT gene-linked polymorphic region (HTTLPR) in the promoter and intron 2 variable number of tandem repeats (VNTR), in a sample of 105 ASD patients, their parents, and 52 control children. Quantitative transmission disequilibrium test (QTDT) results showed a significant effect on 5-HT levels of each SLC6A4 marker (P=0.017 for HTTLPR; P=0.047 for intron 2 VNTR) and of haplotypes of the two markers (P=0.017), with a major contribution of the L.Stin2.10 haplotype (P=0.0013). A 5-HT mean value in the range of hyperserotonemia was associated with the homozygous L.Stin2.10 haplotype (H (1,N=97)=7.76, P=0.0054), which occurred in 33% of hyperserotonemic patients against 6% of patients with normal 5-HT levels (Fisher's exact test: P=0.013, OR=8). Allele interaction at the HTTLPR locus was found, with a significant dominance variance effect on 5-HT levels. We found no transmission disequilibrium of any of the SLC6A4 variants in ASD. Our results show that the SLC6A4 gene is a significant factor in the determination of 5-HT levels, and that specific SLC6A4 variants are associated with an increased risk for hyperserotonemia in our sample of autistic patients. The biological mechanism, however, is unlikely to involve the SLC6A4 gene solely. The associated SLC6A4 alleles likely interact with other genes or environmental factors to produce the abnormally high 5-HT levels observed in this subset of autistic patients, who possibly represent a separate etiological group.

Adolescent↗

Hepatic elemental contents and antioxidant enzyme activities in Algerian mice (Mus spretus) inhabiting a mine area in central Portugal.

In this study the effects of heavy metals (manganese, iron, copper, zinc) and selenium exposure on the hepatic activity of antioxidant enzymes, superoxide dismutase (SOD) and glutathione S-transferases (GST), were appraised on a seasonal basis in Algerian mice (Mus spretus) inhabiting an active copper mine area. A reference population of the same species was considered for comparative purposes. Different patterns of seasonal variation were found in both populations for the manganese, iron and selenium hepatic concentrations and SOD activity. When the two populations were compared, iron and selenium concentrations were enhanced in mice from the polluted area. In addition, SOD activity was significantly decreased in summer in exposed mice, but no other significant changes in SOD and GST activities between sites throughout the year were recorded. However, when seasonal data within each group of mice were pooled, significant differences were found between sites for the average concentrations of manganese, iron and selenium, which are higher in the polluted site. In addition, significant differences were obtained for the average values of SOD and of GST activities, due to simultaneously higher GST values and slightly lower SOD values in the polluted site. The population from the reference site was more homogeneous for all parameters measured than the population from the polluted area. These results, in particular the higher variability in data collected from mice exposed to heavy metals and selenium, combined with the negative associations between biochemical markers and heavy metals, may suggest, despite the good adaptability of the mice to their habitat, biochemical stress due to diminished environmental quality.

Animals↗

The man with the purple nostrils: a case of rhinotrichotillomania secondary to body dysmorphic disorder.

OBJECTIVE: To describe a different type of self-injurious behavior that may be secondary to body dysmorphic disorder (BDD). METHOD: Single case report. RESULTS: We reported a case of an individual who have developed the self-destructive habit of pulling and severely scraping hairs and debris out of the mucous membrane of his nasal cavities. We have proposed the term rhinotrichotillomania to emphasize the phenomenological overlapping between trichotillomania (TTM) and rhinotillexomania (RTM) exhibited by this case. The main motivation behind the patient's actions was a distressing preoccupation with an imaginary defect in his appearance, which constitutes the core characteristic of BDD. The patient was successfully treated with imipramine. CONCLUSION: The case suggests that certain features of TTM, RTM, and BDD may overlap and produce serious clinical consequences. Patients with this condition may benefit from a trial of tricyclics when other effective medications, such as serotonin reuptake inhibitors, are not available for use.

Adrenergic Uptake Inhibitors↗

Potential therapeutic application of the association of vitamins C and K3 in cancer treatment.

The decision of stressed cells to die or to survive is made by integrating signals at different levels through multiple check points. However, initiation and continued progression toward cell death by apoptosis in cancer cells may be blocked by mutation of the tumor suppressor p53 or overexpression of members of the bcl-2 family of proteins. The existence of such mechanisms indicates that cancer cells lose the controls regulating their cell cycle. Therefore, the activation of their programmed cell death appears as a major therapeutic target. Oxidative stress can stimulate growth, trigger apoptosis, or cause necrosis depending upon the dose and the exposure time of the oxidizing agent. A large body of evidence supports the idea that oxidative stress induced by redox cycling of vitamins C and K(3) in association surpasses cancer cellular defense systems and results in cell death. The molecular mechanisms underlying such a process are, however, still unknown. Indeed, several types of cell death may be produced, namely autoschizis, apoptosis and necrosis. Combined vitamin C and K(3) administration in vitro and in vivo produced tumor growth inhibition and increased the life-span of tumor-bearing mice. CK(3)-treatment selectively potentiated tumor chemotherapy, produced sensitization of tumors resistant to some drugs, potentiated cancer radiotherapy and caused inhibition of the development of cancer metastases without inducing toxicity in the host. We propose the association of vitamins C and K(3) as an adjuvant cancer therapy which may be introduced into human cancer therapy without any change in the classical anticancer protocols, and without any supplementary risk for patients.

Animals↗

Sclerosis of gross cysts of the breast: a three-year study.

Breast cysts can be separated into two types: Type I cyst with a lining epithelium which shows apocrine metaplasia, and Type II cyst with an epithelium which is markedly attenuated or absent. The risk of subsequent breast cancer among patients with Type I cysts can be up to 4. The standard treatment is fine needle aspiration, but 20% of the cysts recur. Pharmacological treatment has been tried, which reduces size and volume, but has side-effects and a high recurrence rate post-treatment occurs. The objectives of this prospective study were to sclerose the cyst, induce its regression and prevent or reduce recurrence rate, with the administration of a sclerosing solution (Sclerovein) within the cyst post-aspiration. Fifty-seven patients were followed in the study, 37 with Type I cysts and 20 with Type II cysts. At the end of six months all patients with Type II cysts had no detectable cyst. On the other hand, two patients still had a residual Type I cyst. At the end of three years our recurrence rate appears to be less than 2%, with one patient with a possible recurrence. No significant side-effects were observed. The use of Sclerovein is a simple and safe alternative in the treatment of recurring cysts.

Adolescent↗

The effect of crop protection strategy on pest and beneficials incidence in protected crops.

This study took place in the Oeste region from 1996-1999 and it intended to analyse if the crop protection strategy followed by the farmer influenced the arthropod incidence and the natural control in protected vegetable crops under Mediterranean conditions. The observations were made fortnightly (Autumn/Winter) or weekly (Spring/Summer) in 30-60 plants/parcel (1 plant/35 m2) in order to evaluate incidences. Samples of pests and natural enemies were collected for systematic identification in two greenhouses for each protection strategy (traditional chemical control (TCC), integrated pest management (IPM) and pest control allowed in organic farming (OF)) in lettuce, tomato, green beans and cucumber. Data on incidence of mites, aphids, caterpillars, leafminers, whiteflies, thrips and respective natural enemies were registered as well as phytosanitary treatments performed (farmers' information and/or in loco traces). The leafminers were the pest whose incidence more often presented significant statistical differences between the studied protection strategies. In relation to this pest, the main results obtained were: a higher feeding punctures incidence in TCC than in IPM; higher incidence of adults, mines and feeding punctures in TCC than in OF; and a higher mines' incidence in IPM than in OF. Both in TCC and IPM high percentages of plants with mines were found although without an adult proportional presence. In the first case this was due to the repeatedly phytosanitary treatments applied; in the second case it was due to the natural control, since in IPM and OF greenhouses the collected larvae were mostly parasitized or dead. In spite of the fact these two strategies have as final result a similar mines and adults incidence, their production and environmental costs are quite different. Significant differences at the beneficials' population level between TCC greenhouses and IPM or OF greenhouses were found. As the farmers did no biological treatments these differences are related to different levels of beneficial populations due to different secondary effects of the pesticides applied.

Animals↗

Elevated vulnerability to oxidative stress-induced cell death and activation of caspase-3 by the Swedish amyloid precursor protein mutation.

The Swedish double mutation (KM670/671NL) of amyloid precursor protein (APPsw) is associated with early-onset familial Alzheimer's disease (FAD) and results in from three- to sixfold increased beta-amyloid production. The goal of the present study was to elucidate the effects of APPsw on mechanisms of apoptotic cell death. Therefore, PC12 cells were stably transfected with human APPsw. Here we report that the vulnerability of APPsw-bearing PC12 cells to undergo apoptotic cell death was significantly enhanced after exposure to hydrogen peroxide compared to human wild-type APP-bearing cells, empty vector-transfected cells, and parent untransfected cells. In addition, we have analyzed the potential influence of several mechanisms that can interfere with the execution of the apoptotic cell death program: the inhibition of cell death by the use of caspase inhibitors and the reduction of oxidative stress by the use of (+/-)-alpha-tocopherol (vitamin E). Interestingly, oxidative stress-induced cell death was significantly attenuated in APPsw PC12 cells by pretreatment with caspase-3 inhibitors but not with caspase-1 inhibitors. In parallel, caspase-3 activity was markedly elevated in APPsw PC12 after stimulation with hydrogen peroxide for 6 hr, whereas caspase-1 activity was unaltered. In addition, oxidative stress-induced cell death could be reduced after pretreatment of APPsw cells with (+/-)-alpha-tocopherol. The protective potency of (+/-)-alpha-tocopherol was even greater than that of caspase-3 inhibitors. Our findings further emphasize the role of mutations in the amyloid precursor protein in apoptotic cell death and may provide the fundamental basis for further efforts to elucidate the underlying processes caused by FAD-related mutations.

Alzheimer Disease↗

Sexual dysfunction: a neglected complication of panic disorder and social phobia.

Little is known about sexual dysfunctions comorbid with anxiety disorder. The aim of this study is to evaluate retrospectively the sexual function of social phobic patients in comparison with a panic disorder sample. Using a semistructured interview (SCID-I), 30 patients with social phobia and 28 patients with panic disorder were examined. The DSM-IV criteria were employed to diagnose sexual dysfunctions in this sample; however, the "C" criterion, which states that "the sexual dysfunction cannot be related to other Axis I disorders," was excluded. Panic disorder patients reported a significantly greater proportion of sexual disorders compared with social phobics: 75% (21/28) vs. 33.3% (10/30) (p = .0034). Sexual aversion disorder was the most common sexual dysfunction in both male (35.7%; 5/14) and female (50%; 7/14) panic disorder patients, and premature ejaculation was the most common sexual dysfunction in male social phobic patients: 47.4% (9/19). These results suggest that sexual dysfunctions are frequent and neglected complications of social phobia and panic disorder.

Adult↗

[Recurrent pericardial effusion --a case of cardiac angiosarcoma].

A case of angiosarcoma of the right atrium in a 59-year-old woman is reported, presenting as a recurrent hematic pericardial effusion. The usefulness of echocardiography in making the diagnosis is emphasized. The tumor was already disseminated at the time of the diagnosis. The patient was on palliative therapy, dying a few months later. The histological examination was done at autopsy. This case highlights the difficulty in diagnosis and the various modalities available for an accurate diagnosis of a rare clinical entity. It has a rapid and aggressive course with a very poor prognosis.

Female↗

Pressure patches for membranes: the induced pinch of a grafted polymer.

Achieving control of membrane shape and topology is of crucial importance to regulate function and performance of many systems in the realms of biology, physics, and chemical sciences. The design of a kit of versatile microscopic tools for tuning the shapes of fluid membranes relies ultimately on the possibility of tailoring molecules for applying a given, well-chosen force, to the self-assembled interfaces. Here we discuss theoretically the ability of grafted polymers to perform as mesoscopic pressure patches. We compute the pressure that a grafted polymer applies to the supporting surface. We also show that this entropic pressure leads to a well-defined pinched form of the membranes. Moreover, new membrane-mediated forces result from the action of these pressure tools, enabling action upon their spatial distribution along the membrane surface.

Elasticity↗

[Quantitative electroencephalography in obsessive-compulsive disorder: preliminary results].

The predictive value of quantitative electroencephalography (EEGq) was investigated with regard to the pharmacological treatment of 10 non-medicated obsessive-compulsive disorder (OCD) patients diagnosed according to DSM-IV criteria. The following variables were selected: bipolar relative power in alpha band for Cz-C3, Cz-C4, T3-T5, T4-T6, T3-F7 and T4-F8; bipolar relative power in theta band for Cz-C3, Cz-C4, T3-T5, T4-T6, T3-F7 and T4-F8; and monopolar relative power in theta band for Fp1, Fp2, F7, F3, Fz, F4 and F8. There was statistically significant deviations in five patients with regard to bipolar relative power in alpha band for central regions when compared to normative data bank (control group). This group of patients had a significantly lower age of OCD onset and worse response to pharmacotherapy with serotonin reuptake inhibitors.

Adolescent↗

[Wertheim-Meigs procedure. 10-year results].

Wertheim-Meigs hysterectomy is used in the treatment of cervical cancer, but since 1988 we have also used it to stage and treat endometrial carcinoma. To evaluate the morbidity of Wertheim Meigs hysterectomy as well as node invasion incidence and its correlation with other prognostic factors, the authors made a retrospective study of 112 patients, from October 1986 to March 1996. Among the 112 cases evaluated, 52% had cervical carcinoma and 48% had endometrial carcinoma; mean ages were 45 +/- 10 and 60 +/- 8 years (p < 0.005). FIGO stage distribution was: I-94.8 and 33.3%; II-5.2 and 51.9%; III-0 and 13%; IV-0 and 1.8%, for cervical and endometrial carcinoma. Hemorrhagic and traumatic accidents happened in 24.3% and 1.7% respectively. We had 15.5% early post operative complications and 1.7% late post operative ones. The mean duration of surgery and hospitalization was 163 +/- 29 minutes and 10 +/- 5 days. Pelvic lymphadenectomy was performed in 70% of patients and para-aortic nodes were also excised in the other 30%. The mean number of lymphatic nodes excised were 17 +/- 9. Pelvic node invasion was found in 9% and in 3.7% of para-aortic ones. When we studied endometrial cancer, we found a positive correlation between external myometrium invasion and lymphovascular invasion and positive node (p < 0.05). From the data available we may conclude that the complication rate of Wertheim Meigs is quite important, even though all but one complication were transitory. It may be possible to make a better selection of patients who need this surgical procedure by correct evaluation of risk factors.

Endometrial Neoplasms↗