Biomedical subjects

C Vera

Publications and source records attributed to C Vera.

At least 19 recordsLinked to original sources

PubMed2004

[Long-term impact of a mass treatment by praziquantel on morbidity due to Schistosoma haematobium in two hyperendemic villages of Niger].

Although it is established that the treatment by praziquantel reduces the urinary lesions due to Schistosoma haematobium, the frequency of mass treatment necessary to maintain a low morbidity level remains poorly known. The objective of this work was to study the impact over three years of a single praziquantel mass treatment on schistosomiasis morbidity in two different systems of disease transmission in Niger. The study was performed in 2 villages hyperendemic for schistosomiasis in the South-West of Niger presenting respectively 2 different systems of schistosomiasis transmission: Koutoukalé-Zéno (K Zéno), located close to an irrigated area of the Niger River Valley where the transmission is permanent, and Téguey located along a temporary pond where the transmission is seasonal. After the initial evaluation (1994), we carried out a survey 3 years later (1997) except in K. Zéno where an intermediate evaluation was performed 10 months after the initial survey (1995). Approximately 300 randomised people have been examined as follows: macroscopic examination of urine and reagent sticks for macro- and micro-haematuria, filtration and microscopic examination of urine for Schistosoma eggs, and ultrasound scan of the urinary tract for morbidity. The therapeutic coverage has reached 69.9% in K. Zéno and 78.2% in Téguey. The prevalence of infestation decreased from 74.1% to 56.4 % in K. Zéno (p < 0.001) and from 65.3% to 30.4% in Téguey (p < 0.001) at the end of the 3 years. The prevalence of heavy infestation (eggs > or = 50) went in the same time from 9.9% to 12.8% (p = 0.3) in K. Zéno and from 9.1% to 3.3% in Téguey (p = 0.01). Using ultrasound scan, the prevalence of the bladder lesions reached its previous level in both villages. However the prevalence of hydronephrosis decreased from 21.1% to 3.9% in K. éno (p < 0.001) and from 12.6% to 4.2% in Téguey (p < 0.001). Three years after the single mass treatment, the morbidity did not reach the initial level. The effectiveness of the treatment is better in the pond system where the transmission is seasonal. The lesions of the upper tract decreased more slowly than the bladder lesions, but a long time after the treatment. The re-infestation induced the re-appearance of the bladder lesions sooner than the lesions of the upper tract. The periodicity of the treatment should be variable according to the transmission system. It should occur every 2 years in irrigated areas and could be delayed (3 years) in temporary ponds. The control was beneficial in the pond system and induced a significant reduction of the severe lesions.

Adolescent↗

PubMed2001

[Continued ultrasonic follow-up of children infected with Schistosoma haematobium after treatment with praziquantel].

During a Schistosoma haematobium morbidity control program in Niger, we conducted a survey to describe rhe resolution of lesions after treatment with praziquantel. to determine reinfection rates and to define retreatment schedules. 114 schoolchildren (7-15 years old) living in an hyperendemic village underwent 10 successive examinations over 34 months following an initial evaluation and the administration of 40 mg/kg of praziquantel. All children, whether apparently infected with S. haematobium or not, were treated. Egg output, microhaematuria, visual aspect of urine and abnormalities of the urinary tract by ultrasound were assessed. The initial prevalence tif infection was 74.5%. Reinfection began 5 months after treatment and the final prevalence was 47.1%. Bladder abnormalities decreased rapidly, but incompletely, probably due to reinfestation: initial prevalence: 89.5%). Their prevalence increased 8 months after treatment to 72.4% at month 34. Dilatations of the upper urinary tract regressed more slowly but constantly until the end of the study (initial prevalence: 43%; 4.6% at month 34), Three years after treatment, despite reinfection, the general morbidity level (prevalence and severity of lesions) was lower than at baseline in our cohort, which would suggest the advantage of a long interval between mass treatments in the epidemiological context of our survey.

Adolescent↗

PubMed2000

Tropomodulin-binding site mapped to residues 7-14 at the N-terminal heptad repeats of tropomyosin isoform 5.

Tropomodulin is a globular protein that caps the pointed end of actin filaments by complexing with the N-terminus of a tropomyosin (TM) molecule. TM consists of coiled coils except for the N-terminus, which may be globular. Here we report that human TM isoform 5 (hTM5) lacking the N-terminal 18 residues lost its binding activity toward tropomodulin. We further characterized the tropomodulin-binding site by creating a series of deletion and missense mutations within this region, followed by a solid-phase binding assay. I7, V10, and I14, hydrophobic residues located at the a and d positions of N-terminal heptad repeats involving intertwine, are essential for tropomodulin binding. R12, a positively charged residue at the f position, is also involved in recognition. In contrast, A2R and G3Y mutations, each creating a bulky N-terminus, did not alter the binding. In addition, rat TM5b, which differs from hTM5 in residues 4-6, exhibits a similar binding affinity. The tropomodulin-binding site, therefore, is mapped to residues 7-14 at the beginning of the long heptad repeats. Column chromatography revealed that hTM5 mutants remained capable of dimerization. Results also suggest tropomodulin has a groove-type, rather than a cavity-type, binding site for hTM5. We also mapped the epitope of monoclonal antibody LC1 to residues 4-10 of hTM5 and showed the competition between mAb LC1 and tropomodulin in hTM5 binding. Since the N-terminal residues need to overlap with the C-terminus of TM in their head-to-tail association, this investigation elucidates the mechanisms by which the tropomodulin-hTM5 complex is formed and functions in regulating the actin filaments.

Amino Acid Sequence↗

PubMed2000

Sleep in right hemispherectomized patients: evidence of electrophysiological compensation.

OBJECTIVES: The goal of this study is to provide a better understanding of the role of the cortex in sleep's macro- and microstructure modulation. METHODS: Sleep architecture and phasic events were investigated in 4 patients having undergone right functional or anatomical hemispherectomy and 8 control subjects. Between-groups differences were assessed using the Wilcoxon-Mann-Whitney test. RESULTS: Findings provide evidence for overall similarity between patients' and control subjects' left hemispheric sleep architecture. In addition, results clearly indicate that it is possible to detect electrical activity over the operated side of a hemispherectomized patient's brain, even when resection of the hemi-cortex has been complete. Finally, findings provide evidence for similar left and right hemispheric relative spectral activities and for an increase in fast activity bands over the intact hemisphere in anatomical hemispherectomized patients. CONCLUSIONS: This study provides evidence that right hemispherectomy does not produce significant sleep architecture alterations as recorded over the intact hemisphere. In addition, residual activity detected over the operated side in anatomical hemispherectomized patients is interpreted as resulting from volume conduction originating from generators located in the intact hemisphere. Finally, there is strong evidence for electrophysiological compensation in the intact hemisphere following complete resection of the contralateral hemi-cortex.

Adolescent↗

PubMed2000

[Quality control during ultrasonographic evaluation of morbidity due to Schistosoma haematobium in Niger].

Within the framework of a campaign to control urinary schistosomiasis in Niger, a quality control audit was performed on ultrasonographic assessment of morbidity due to Schistosoma haematobium. The purpose of this audit was to determine variance and reproductibility of epidemiological data provided by two trained independent observers. Three parameters were studied, i.e.,: interobserver variability on matched data, interobserver variance at the community level on the same or different subjects, including some after treatment with praziquantel, and intra-observer variance. A total of 1750 ultrasound examinations were carried out on 1416 inhabitants from 10 hyperendemic villages (70 p. 100 schoolchildren) according to a slightly modified version of the WHO Cairo protocol. Inter-observer variance at the individual level was high for some elementary abnormalities of the bladder. Variance was around 20 p. 100 for the 2 main indicators, i.e. presence of at least one bladder lesion and dilatation of the upper urinary tract. At the community level, inter-observer variance was moderate and the two observers' global assessment of morbidity due to Schistosoma haematobium was the same. Variations of morbidity related to level of endemicity were given perceived in parallel. Similar findings were noted for the intra-observer variability at the individual or community level. Ultrasound examination is supposed to furnish reliable morbidity data for selecting communities at risk and scheduling treatments during schistosomiasis control programs. The results of this study show that the level of inter- and intra-observer variance in ultrasonographic assessment in Niger is compatible with this critical role.

Child↗

PubMed1999

[Preliminary evaluation of usable indicators during a control program for urinary bilharziosis in Niger].

The performance of several indirect screening tests was evaluated during the start-up phase of a urinary schistosomiasis control program in Niger. Urine tests were carried out on a total of 354 children attending 3 primary schools on five consecutive days. Tests included filtration of 10 ml of urine, search for microscopic hematuria using reagent strips, and gross examination of urine. In addition a questionnaire was administered on the first day to identify signs of dysuria and hematuria. Repeat testing had a strong effect on the epidemiological profile of urinary schistosomiasis in the 3 schools. Although day-to-day counts varied greatly, egg excretion could be considered as high in all infected subjects. The screening sensitivity of urine filtration was low when the level of endemicity was moderate (up to 55 p. 100). Microscopic hematuria was common. However the sensitivity of this method was overestimated in comparison with urine filtration alone and use of reagent strips can be inconvenient. Using carefully defined diagnostic criteria, gross examination of urine was as effective as urine filtration and easier to perform. The value of the questionnaire for evaluation of morbidity was low despite relatively good performance of the diagnostic techniques. The children's responses concerning hematuria were not objective and questions concerning dysuria were poorly understood and time-consuming. In the next phase of study, these findings will be validated by ultrasound imaging.

Child↗

PubMed1999

[Community-acquired pneumonia in the elderly requiring hospitalization. Clinical features and prognosis].

We evaluated retrospectively 96 patients older than 64 years admitted with the diagnosis of Community Acquired Pneumonia (CAP) in order to describe the clinical features, evaluate severity and assess prognostic factors. During an 18-month period 100 cases of CAP were included. Average age was 82.3 years +/- 8.3 (+/- SD). By the time of admission, cough and fever were found in 35% of cases and 48% had altered mental status. Fourteen per cent needed mechanical ventilation. Etiology was determined in 21% of cases. Most common pathogens were S. pneumoniae (38.1%), S. aureus (19%) and H. infuenzae (14.3%). Overall mortality was 29%. The most commonly present criteria of severity were tachypnea (respiratory rate > 30) and a PaO2/FIO2 ratio < 250. Severe pneumonia was found in 60% of patients and mortality in that group was 40%. Multivariate analysis demonstrated that some independent prognostic factors were associated with higher mortality: requirement of vasopressors (Odds Ratio [OR] = 22.0; 95% confidence interval [CI] = 1.9-249.5), oliguria (OR = 9.9; CI = 1.5-66.2), previous neurologic disease (OR = 8.2; CI = 1.8-36.6), PaCO2 > 44 mm/Hg (OR = 6.9; CI = 1.1-43.2), and creatinine > 1.4 mg/dl (OR = 4.7; CI = 1.2-19.1). We conclude that CAP features in elderly patients requiring hospitalization are atypical, severe presentations are frequent and mortality is high. Prognostic factors as found in this study can help the evaluating physician to identify those who require special care.

Aged↗

PubMed1997

Two SRY-negative XX male brothers without genital ambiguity.

We report a Mexican family in which two sibs were identified as "classic" XX males without genital ambiguities. Molecular studies revealed that both patients were negative for several Y sequences, including SRY. A review of familial cases disclosed that this is the first family where a complete male phenotype was observed in Y-negative XX male non-twin brothers. These data suggest that an inherited loss-of-function mutation, in a gene participating in the sex-determining cascade, can induce normal male sexual differentiation in the absence of SRY.

Adult↗

PubMed1997

REM sleep dream mentation in right hemispherectomized patients.

Investigations of dream mentation in brain damaged patients have shed some light on the controversial issue of cerebral lateralization of dreaming. To examine further the relationships between brain function and dreaming, we studied REM sleep dream recall and content in four patients having undergone right functional or anatomical hemispherectomy and eight matched control subjects. Patients were found to have the capacity to report dreams to much the same extent as control subjects. Further, the patients' dream content was overall similar to that of the control subjects. The results provide strong evidence that dreaming is not a right-hemisphere function, and that the left hemisphere may be more critical for the generation of dreams. In addition, some characteristics of hemispherectomized patients' dream content (characters, smells) are consistent with the possibility that a history of epilepsy may influence REM sleep imagery over the long term.

Adolescent↗

PubMed1996

Hypotensive effect of crude root extract of Solanum sisymbriifolium (Solanaceae) in normo- and hypertensive rats.

The hypotensive effect of the crude hydroalcoholic extract from root of Solanum sisymbriifolium Lam. (Solanaceae) was investigated both in normotensive and hypertensive rats. The intravenous administration of the extract (50 and 100 mg/kg) produced a significant decrease in blood pressure in anaesthetized hypertensive (adrenal regeneration hypertension + deoxycorticosterone acetate (ARH + DOCA)) rats. Oral administration of the extract (10, 50, 100 and 250 mg/kg) also produced a dose-dependent hypotensive effect in conscious hypertensive animals. In anaesthetized normotensive rats, the extract (50 and 100 mg/kg, i.v.) also induced hypotension in a dose-dependent manner. Lastly, no significant effect on blood pressure was produced by the extract when administered orally (10, 50, 100, 250, 500 and 1000 mg/kg) to conscious normotensive rats.

Administration, Oral↗

PubMed1995

Value of morphometry as an independent prognostic factor in renal cell carcinoma.

Nuclear morphometry was performed in 159 adenocarcinomas of the kidney. The mean and SD of the following nuclear parameters were calculated: area, perimeter, major axis, minor axis and a shape factor. Median survival, including all stages, was 72 months and cumulative survival at 5, 10 and 15 years of 50, 42 and 33%, respectively. Values of morphometric parameters, except for shape factor, tend to increase in proportion to stage. Nuclear area was the best parameter to predict the variability in survival time. The Cox regression model was performed for each stage, and the relationship with length of survival time was studied. For stage T1-2 N0 M0, nuclear area was the only variable chosen as an independent significant predictor of outcome. For the rest of the stages, no variables were selected as predictors at any significant level.

Adult↗

PubMed1992

The mouse as a suitable host for an isolate of Schistosoma haematobium from Niger.

The host-parasite relationships of a Schistosoma haematobium isolate, originating from Niger, and the white mouse are described. Swiss OF1 albino mice were exposed individually to 200 cercariae and worms were recovered 9, 12, 16 and 20 weeks post infection. The mean worm returns ranged between 10.54 and 13.05% and did not alter significantly between 9 and 20 weeks post infection. The sex ratio of worms was always in favour of males; from 7.09:1 at 9 weeks after infection it decreased regularly to 3.28:1 at 20 weeks. Male worms reached a mean length of 8.72 mm at 20 weeks. From the 12th week post infection, a high number of eggs was found in the liver and gut. At 20 weeks, eggs were also found in the bladder. Viable eggs and infective miracidia were obtained. The infection of Bulinus truncatus from Niger succeeded with a mean rate of 61% after the first passage through mice. The isolate of S. haematobium was maintained in the laboratory during 3 successive passages through mice. These entirely new results are very probably linked to genetic characteristics peculiar to the S. haematobium populations from Niger.

Animals↗

PubMed1992

[Prevalence of false seropositivity for syphilis in a population of pregnant women].

A retrospective chart review of 439 pregnant women with positive syphilis serology detected with VDRL was made. One hundred twenty two women (27.7%), aged 17 to 43 years and with a gestational age ranging from 8 to 38 weeks, had false positive VDRL tests. None of these patients had a titer over 1:4 and 65% had a weakly reactive VDRL. Forty percent of women were diagnosed as having an early latent syphilis and 20% as late latent syphilis. Due to the high frequency of these later diagnoses in women with VDRL titers below 1:2, with no risk factors and negative sexual partners, post partum follow up is essential to detect cases with false positive FTA-ABs tests.

Adolescent↗

PubMed1991

Renal cell carcinoma: late recurrence in 2 cases.

We present 2 patients with late recurrence 16 and 11 years after nephrectomy for renal cell carcinoma. Metastases were solitary and their location very uncommon (vastus externo muscle and colon). In the reviewed series of 5,758 patients with renal cell carcinoma only a temporal muscle metastasis and another in the colon were observed but none of them was solitary.

Aged↗

PubMed1990

[Contribution of echography to the study of the andrologic patient].

Our experience in the ultrasonographic evaluation of the prostate and seminal vesicles in prostatitis and male infertility are reported herein. In our view, this noninvasive imaging technique must be performed before recurring to other methods that involve manipulation. Similarly, we discuss the possibilities of duplex Doppler in the diagnosis of vascular disorders in the male consulting for impotence. We believe this simple noninvasive imaging technique can significantly reduce the number of patients that may require cavernosometry and cavernosography.

Erectile Dysfunction↗

PubMed1990

[Urinary schistosomiasis in the Saharan mountain plateau of Air (Republic of Niger)].

In two villages of the Aïr (Republic of Niger) the authors have found a Schistosoma haematobium overall prevalence of 24.1% at Timia and 43.5% at El Meki. At El Meki, the distribution of prevalences by age group accords to that which is usually found. The maximum is found in the 5-14 years age group and highest in men than in women. At Timia, the prevalence among young pupils is low, this seems to be due to the application of sanitary education measures. At El Meki, Bulinus truncatus rohlfsi, present in a permanent pool ("guelta") is the intermediate host of schistosomes. The role of this snail in the transmission of urinary schistosomiasis at Timia has not been demonstrated. The role of Bulinus senegalensis, found in both villages has yet to be proved.

Adolescent↗

PubMed1984

[Factor XII deficiency].

The work presents classical form and variant of F XII deficiency. Although a rare disorder, F XII deficiency can lead to bleeding, particularly after injuries and surgeries. Further laboratory investigation of patients with pathological APTT is required.

Adult↗

PubMed1980

[Copper and zinc levels in nails of children with cystic fibrosis, carriers and healthy controls (author's transl)].

Authors study copper and zinc levels and the ratio zinc/copper, by atomic absorption spectrophotometry, in nails of children with cystic fibrosis, suspected carriers, relatives of patients, and healthy controls, the latest forming two different groups. A significant increase of copper and zinc levels in nails of cystic fibrosis patients compared to the controls is found. However, there were no significant differences with regard to the carriers. It is concluded that, in spite of significant findings, this method should not be used routinely because of the large fluctuations produced by the weight of nails, the sensitivity of the resonance line and the variations in these elements concentration on nails surface.

Adolescent↗