Search PubMed⌕ Search

Biomedical subjects

C Moreira

Publications and source records attributed to C Moreira.

At least 37 records · Page 2Linked to original sources
PubMed2000

The barium enema in constipation: comparison with rectal manometry and biopsy to exclude Hirschsprung's disease after the neonatal period.

BACKGROUND: The diagnosis of Hirschsprung's disease is usually made in neonates but often considered in older infants and children with constipation: these children may be referred for barium enema. Since it is widely accepted that a normal barium enema does not exclude Hirschsprung's disease, some children, after a normal enema, undergo more invasive procedures such as rectal manometry or biopsy. Our study asked how frequently a diagnosis of Hirschsprung's disease was made by biopsy or manometry in children who had normal barium enema. MATERIALS AND METHODS: We reviewed the medical records and barium enemas of 54 patients older than 28 days with constipation or difficulty passing stool who had a barium enema followed by manometry and/or biopsy. RESULTS: Forty-eight patients had normal enemas: 24 of those patients had biopsies, 16 had manometry, and 8 both manometry and biopsy. Only 1 had manometry suggestive of Hirschsprung's disease, confirmed by biopsy. Six patients had abnormal enemas. Five had biopsy and manometry compatible with Hirschsprung's disease; one had a normal biopsy and manometry study. CONCLUSION: The barium enema is a good initial screening test for Hirschsprung's disease in severely constipated children since it correlates well with manometry and biopsy. The enema is particularly useful in centers without easy access to pediatric gastroenterology services, and a normal enema in this setting allows the continuation of medical therapy with further evaluation only if there is a lack of response. An abnormal enema, however, requires referral to a facility equipped to perform confirmatory manometry or biopsy.

Adolescent↗
PubMed2000

[Sickle cell disease in children in Dakar, Senegal].

AIM OF THE STUDY: To determine the socioeconomic, clinical and biological aspects of sickle cell disease (SCD) in Senegalese children and adolescents, we retrospectively analysed all records of follow-up attending patients in the Albert Royer Children Hospital of Dakar (Senegal). RESULTS: Homozygous sickle cell (SS) was the most frequent genotype (307 cases). Sickle cell hemoglobin C (13 cases) and sickle cell beta-thalassemia (three cases) were uncommon. Patients were aged from five months to 22 years (mean age: eight years). Most of them came from poor families. The mean number of children was five in patients' families, with at least two cases of SCD in 60% of them. Immunization against hepatitis B virus (10.2%), Haemophilus influenzae b (8.4%), Salmonella (8.7%) and Streptococcus pneumoniae (21.4%) was insufficiently performed, because of its relatively high cost. Only 30% of the patients had received a blood transfusion. Painful crises occurred less than three times a year in 74% of the cases. Complications such as acute chest syndrome (1%), stroke (1%), cholelithiasis (9%), meningitis (0.4%), septicemia (2%) and osteomyelitis (6%) were rare. Mean steady state hemoglobin (Hb) and hemoglobin F(HbF) levels were 8.27 +/- 1.36 g/dL and 6.8 +/- 5.9% respectively among SS patients. No correlations were found neither between Hb and HbF nor between these parameters and the frequency of complications. Eleven patients (1.1% per year of follow-up) died, and infection was the main cause of death (73%). CONCLUSION: In comparison with published data, SCD seems to have mild severity in Senegalese children and adolescents in spite of poor follow-up conditions. In addition to genetic factors, environmental factors might have an important role in disease tolerance.

Adolescent↗
PubMed2000

Tepidimonas ignava gen. nov., sp. nov., a new chemolithoheterotrophic and slightly thermophilic member of the beta-Proteobacteria.

A bacterial isolate with an optimum growth temperature of about 55 degrees C was recovered on a medium composed of one part Kligler's iron agar and four parts of Thermus Agar from the host spring at São Pedro do Sul in central Portugal. Phylogenetic analyses using the 16S rRNA gene sequence of strain SPS-1037T indicated that the new organism represented a new genus and species of beta-Proteobacteria. The major fatty acids of strain SPS-1037T are C16:0 and C17:0. Ubiquinone 8 is the major respiratory quinone, and the major polar lipids are phosphatidylethanolamine and phosphatidylglycerol. The new isolate is aerobic and chemolithoheterotrophic. Thiosulfate and tetrathionate were oxidized to sulfate. The growth yield of the organism was improved by the addition of thiosulfate to media containing organic carbon sources, but the organism did not grow autotrophically under the conditions examined. Heterotrophic growth of strain SPS-1037T occurs on amino acids and organic acids, but this organism does not assimilate carbohydrates. On the basis of the phylogenetic analyses, and physiological and biochemical characteristics, it is proposed that strain SPS-1037T represents a new genus and a new species for which the name Tepidimonas ignava is proposed.

Base Composition↗
PubMed2000

Inverse agonism and constitutive activity as functional correlates of serotonin h5-HT(1B) receptor/G-protein stoichiometry.

This study evaluated the influence of receptor/G-protein (R:G) stoichiometry on constitutive activity and the efficacy of agonists, partial agonists, and inverse agonists at human (h) 5-hydroxytryphamine 1B (5-HT(1B)) receptors. Two Chinese hamster ovary cell lines were used; they expressed 8.5 versus 0.4 pmol h5-HT(1B) receptors/mg (determined by [(3)H]GR125,743 saturation analysis) and 3.0 versus 1.5 pmol receptor-activated G-proteins/mg [determined by guanosine-5'-O-(3-[(35)S]thio)-triphosphate ([(35)S]GTPgammaS) isotopic dilution], respectively. Thus, they displayed R:G ratios of approximately 3.0 (RGhigh) and approximately 0.3 (RGlow), respectively. In competition-binding experiments, the agonists, 5-HT and sumatriptan, displayed fewer high-affinity (HA)-binding sites and the partial agonists, BMS181, 101 and L775,606, displayed decreased affinity in RGhigh versus RGlow membranes. In contrast, the inverse agonists, SB224,289 and, to a lesser extent, methiothepin, showed increased affinity. In G-protein activation experiments, both basal and 5-HT-activated [(35)S]GTPgammaS binding were higher in RGhigh than in RGlow membranes. Constitutive activity (determined by inhibition of basal [(35)S]GTPgammaS binding with GTPgammaS in the absence of receptor ligands) was more pronounced in RGhigh versus RGlow membranes, as revealed by the >5-fold greater proportion of HA sites. Correspondingly, the negative efficacy of inverse agonists was strikingly augmented, inasmuch as they suppressed approximately two-thirds of HA [(35)S]GTPgammaS binding in RGhigh membranes, but only approximately one-third in RGlow membranes. Furthermore, the efficacy of partial agonists was greater at RGhigh versus RGlow membranes, as estimated by their ability to enhance [(35)S]GTPgammaS binding. In conclusion, an increase in R:G ratios at h5-HT(1B) receptors was associated with an increase in relative efficacy of partial agonists and, most notably, an increase in both constitutive G-protein activation and negative efficacy of inverse agonists.

Animals↗
PubMed2000

[Persistent diarrhea]

INTRODUCTION: Persistent diarrhea has high impact on infantile morbidity and mortality rates in developing countries. Several studies have shown that 3 to 20% of acute diarrheal episodes in children under 5 years of age become persistent. DEFINITION: Persistent diarrhea is defined as an episode that lasts more than 14 days. ETIOLOGY: The most important agents isolated in persistent diarrhea are: Enteropathogenic E. coli (EPEC), Salmonella, Enteroaggregative E. coli (EAEC), Klebisiella and Cryptosporidium. CLINICAL ASPECTS: In general, the clinical characteristics of patients with persistent diarrhea do not change with the pathogenic agent. Persistent diarrhea seems to represent the final result of a several insults a infant suffers that predisposes to a more severe episode of diarrhea due to a combination of host factors and high rates of enviromental contamination. Therefore, efforts should be made to promptly treat all episodes of diarrhea with apropriate follow-up. THERAPY: The aim of the treatment is to restore hydroelectrolytic deficits and to replace losses until the diarrheal ceases. It is possible in the majority of the cases, using oral rehydration therapy and erly an appropriate type of diet. PREVENTION: It is imperative that management strategies also focus on preventive aspects. The most effective diarrheal prevention strategy in young infants worldwide is promotion of exclusive breast feeding.

Journal Article↗
PubMed2000

Nocturnal sleep quality and circadian blood pressure variation.

OBJECTIVE: To verify whether non-dipper behavior is associated with poor nocturnal sleep quality and a higher rate of obstructive sleep apnea than dipper behavior. METHODS: A sample of 36 subjects older than 50 years (mean age = 70 +/- 6.49 years), 8 males and 28 females, 27 (75%) hypertensive and 9 (25%) normotensive, was studied. Nocturnal polysomnography was carried out in the patients' homes. 24-hour ambulatory blood pressure was studied with Spacelabs 90,207 device. The statistical tests used were Student's t test, Pearson's correlation and the Chi-square test. RESULTS: In the overall sample, higher rates of apnea, higher rates of arousal and shorter duration of the REM (rapid eye movement) phase were linked to high levels of nocturnal diastolic blood pressure, with statistical significance (p < 0.01, p < 0.01, p < 0.05 respectively). Sleep fragmentation was associated with the lowest percentages of variation in daytime to nighttime systolic blood pressure (p < 0.03). Apnea rates were significantly higher in the hypertensive group compared to the normal blood pressure population (p = 0.04). We also observed that higher rates of nocturnal apnea corresponded to lower variations in daytime to nighttime systolic blood pressure (p = 0.015) and to a lower dipper index (p < 0.05). Higher indexes of arousal and lower REM latency were associated with higher nocturnal blood pressure, both systolic (p = 0.039 and p = 0.008, respectively) and diastolic (p = 0.003 and p = 0.029, respectively). Sleep efficiency was also negatively correlated with mean levels of nocturnal diastolic blood pressure (p = 0.038). CONCLUSIONS: The quality of nocturnal sleep seems to play an important role in blood pressure levels, particularly in the nocturnal blood pressure profile. A poor quality of nocturnal sleep and the rate of obstructive sleep apnea were associated with non-dipper behavior in the hypertensive population. Sleep evaluation is particularly useful in non-dipper subjects with hypertension.

Aged↗
PubMed2000

[Protein-energy malnutrition in children less than five years old in a rural zone in Senegal (Khombole)].

A survey on 400 children less than five years old living in three villages of the sanitary district of Khombole has been realized from 17th to 25th April 1997 in order to evaluate the existence of malnutrition and the hazard factor linked to it. All children have been weighed and measured. The paraclinic assessment made up by a rate of haemoglobin and a parasitical test of the, motions have been realized on 275 children. The emaciation concerns 8% of the children and the statural backwardness 34.7% of them. The malnutrition is variable from one village to another. The percentage of children suffering from a severe malnutrition according to the classification of Gomez concerns 4.5%. Geophagy, intestinal parasitosis, and anaemia are closely related to chronic malnutrition. The results show the existence of a precarious nutritional situation in rural area requiring new policies of struggle against malnutrition.

Acute Disease↗
PubMed2000

[Protein profile of Senegalese children presenting with nephrotic syndrome].

In Senegal, nephrotic syndrome usually occurs upon malnutrition that confers it its specificity and has brought us to establish the proteinic profile of Senegalese children suffering from it, in the aim to improve its treatment. Twenty children on the average of six years, hospitalized for nephrotic syndrome, were chosen. They were compared to 20 healthy children of the same age group, and 20 other children hospitalized for a non-renal inflammatory syndrome. For each subject were dosed total blood proteins and albumin. The protein electrophoresis has permitted to evaluate the alpha-1, alpha-2, beta and gamma globulins. We have observed predominance of boys with a 2.33 sex ratio. Our patients presenting a nephrotic syndrome were about six years old; no case has been noted before two years. Total proteins and albumin have decreased respectively to 52.10 g/l and 16 g/l. This diminishing is essentially linked to the massive urinary escape of plasmatic proteins and would explain partly the increase of lipids. The alpha-1 globulins were equally lowered but the alpha-2 globulins were increased by 40% of total proteins. Beta globulins have decreased, following the evolution of gamma globulins. In Senegal, The early age of nephrotic syndrome occurrence and the biological perturbations of the proteinic profile, recommend global and quick treatment considering food recovery and nutrition. The correction of these parameters being able to constitute in one hand an element of accessible and reliable supervision, and one the other hand the basis of complete treatment.

Adolescent↗
PubMed1999

[Cholelithiasis and homozygote drepanocytosis in children in Dakar (Senegal)].

BACKGROUND: Cholelithiasis is a well recognized complication of sickle-cell anemia (SCA) because of chronic hemolysis. It is usually asymptomatic but may result in acute cholecystitis or cholangitis. The aim of this study was to assess prevalence of cholelithiasis and its associated factors among Senegalese children and adolescents with SCA. PATIENTS AND METHODS: We analyzed the follow-up records and results of systematic clinical, biological and ultrasonographic examinations in 106 patients with SCA aged 11 months to 22 years (median: 10 years, 6 months), followed up in the Albert-Royer Children's Hospital (Dakar). RESULTS: Cholelithiasis was detected in 9.4% of the patients. Gender, ethnic group, geographic origin and socioeconomic conditions did not have any association with cholelithiasis frequency. The youngest patient with cholelithiasis was 7 years old, and prevalence of cholelithiasis increased with age. The mean age at the beginning of SCA follow-up was higher among patients with cholelithiasis. They were more frequently transfused and tended to present more frequent pain crises and other complications of SCA. We found no spontaneous clinical manifestations attributed to cholelithiasis. Nevertheless, provoked right upper quadrant pain was more frequently observed in patients with cholelithiasis. Fetal hemoglobin, steady-state hemoglobin, reticulocytes count, serum bilirubin, alkaline phosphatase and transaminase levels were not significantly different in these patients, compared to the others. However, those with cholelithiasis had significantly higher mean red cell volume. CONCLUSION: Prevalence of cholelithiasis appears relatively low in Senegalese patients with SCA, probably owing to the tolerance of the Senegal haplotype. Advanced age and severe chronic hemolysis are etiologic factors in evidence. We recommend systematic abdominal ultrasound at least once a year for patients older than 5 years, or when right upper quadrant pain is observed. Cholecystectomy should be performed in cases of cholelithiasis in order to prevent complications.

Adolescent↗
PubMed1999

[Postprandial hypotension].

INTRODUCTION: A decrease in blood pressure (BP) 30 to 60 minutes after food ingestion is a physiologic and asymptomatic event, and is about 10 to 16 mm Hg in elderly subjects, but only 3 to 4 mm Hg in youths. PATIENTS AND METHODS: Sixteen women referred to our hospital with complains of lipothymia were studied. They were compared with a control population of 20 healthy subjects. Clinical, laboratory and electrocardiographic (12 leads and 24 hour "Holter" monitoring) evaluation, and 24 hour BP monitoring were performed. In the BP register, the period between the beginning and until 4 hours after the meal was analysed separately. RESULTS: The systolic and diastolic BP between the two populations was not significantly different (120.6 +/- 14.6 mm Hg and 76.5 +/- 8.9 mm Hg in the study group and 126.8 +/- 10.9 mm Hg and 77.8 +/- 7.2 mm Hg in the controls). The average of the mean BP was also not significantly different (78.7 +/- 11.7 mm Hg vs. 86.8 +/- 5 mm Hg, patients and controls). During the 4 hours after the meal there was a significant decrease (p < 0.01) in the average of the mean BP of the patients, which did not occur in the controls (65.4 +/- 7.3 mm Hg vs. 88.5 +/- 2.5 mm Hg, patients and controls). This postprandial decrease in BP correlated with the patients' symptomatology. CONCLUSIONS: Although physiologic in some individuals, the decrease in postprandial BP can be exaggerated and symptomatic. Outpatient BP monitoring can become a useful instrument in the evaluation of syncope/lipothymia.

Adult↗
PubMed1997

Remodelling: therapeutic opportunities.

Restenosis after angioplasty has been recently attributed to a lack of compensatory enlargement and/or chronic constrictive remodelling, rather than neointimal growth. Also, restenosis occurring after stent has been clearly related to neointimal growth. This clarification has dramatically helped in designing strategies targeted against the appropriate mechanisms. The mechanism of stent-related restenosis has been the most studied and several antiproliferative agents including gene therapy and radioactive stents have been successfully tested. Constrictive remodelling has been identified more recently and its pathophysiological mechanism remains poorly understood. Control of extracellular matrix metabolism might be an important pathway. Moreover, detection of the arteries that will 'enlarge' should avoid any preventive strategy including systematic stenting.

Adaptation, Physiological↗
PubMed1996

Sensitivity of ATPase-ADPase activities from synaptic plasma membranes of rat forebrain to lipid peroxidation in vitro and the protective effect of vitamin E.

The in vitro effects of membrane lipid peroxidation on ATPase-ADPase activities in synaptic plasma membranes from rat forebrain were investigated. Treatment of synaptic plasma membranes with an oxidant generating system (H(2)0(2)/Fe(2+)/ascorbate) resulted in lipid peroxidation and inhibition of the enzyme activity. Besides, trolox as a water soluble vitamin E analogue totally prevented lipid peroxidation and the inhibition of enzyme activity. These results demonstrate the susceptibility of ATPase-ADPase activities of synaptic plasma membranes to free radicals and suggest that the protective effect against lipid peroxidation by trolox prevents the inhibition of enzyme activity. Thus, inhibition of ATPase-ADPase activities of synaptic plasma membranes in cerebral oxidative stress probably is related to lipid peroxidation in the brain.

Adenosine Triphosphatases↗
PubMed1995

Use of glycoconjugates for trypanosomatid taxonomy.

Glycoconjugates from five trypanosomatid genera--Crithidia, Herpetomonas, Endotrypanum, Leishmania, and Trypanosoma--were extracted with Triton X-114 and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by periodic acid-Schiff staining. Most of the glycoconjugates were detected in the hydrophobic phase, indicating the presence of anchored glycoconjugates. All the trypanosomatids expressed a glycoconjugate with a low molecular weight (below 20 kDa) in this phase. In each species, however, a characteristic and specific pattern of glycoconjugates was also observed in both phases. In the hydrophobic phase: 14-29 kDa glycoconjugates in C. guilhermei; 24-70 kDa in C. fasciculata, C. luciliae, E. schaudinni, and T. cruzi Y and G strains; 45-66 kDa in C. oncopelti and H. samuelpessoai; above 36 kDa in T. dionisii; 20-24 kDa, 36-45 kDa, and 70 kDa in L. tarentolae and T. mega. In the hydrophilic phase, typical glycoproteins were observed in some trypanosomatids: 60 kDa in T. mega and T. cruzi Y strain; 70 kDa in H. samuelpessoai; 66 kDa in C. oncopelti; 20-70 kDa in C. luciliae. These findings suggest that Triton X-114-extracted glycoconjugates could be useful markers for trypanosomatid taxonomy.

Animals↗
PubMed1995

Introduction of flocculation into industrial yeast, Saccharomyces cerevisiae saké, by protoplast fusion.

Protoplast fusion was applied to obtain intraspecific fusion in yeast strains in order to overcome restrictions imposed by the natural mating system. Acriflavine was used to construct petite mutants from non-flocculent industrial Saccharomyces cerevisiae saké strain. UV radiation was used to construct ura- mutants from a respiratory competent and highly flocculent S. cerevisiae NCYC869 strain. Fusion products were selected by complementation on minimal medium. The frequency of appearance of prototrophic hybrids was five per 10(5) protoplasts. The stable hybrids showed not only the S. cerevisiae saké characteristics but also flocculation ability, thereby confirming the success of the fusion.

Cell Fusion↗