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M Habib

Publications and source records attributed to M Habib.

At least 55 records · Page 3Linked to original sources
PubMed1996

Comparative studies on urethral function.

Urethral pressure profiles (in vivo), opening pressures, and flow rates at opening pressure (in vitro) were determined for female, male, pregnant, ovariectomized (OVX), OVX and then estrogen-treated, and OVX and then progesterone-treated rabbits. Using the isolated whole-urethra preparation, we determined the opening pressures and flow rates as well as the effects of 250 microM phenylephrine, 250 microM bethanechol, and 120 mM KCl on the urethral opening pressure and flow rate. The results demonstrated that (1) the urethral pressure profiles were similar for male and female rabbits, (2) ovariectomy and pregnancy decreased the urethral pressure profiles, (3) estrogen therapy partially reversed the effect of ovariectomy on the urethra, and (4) progesterone therapy had little effect on the urethral pressure profile. With regard to opening pressure and flow, (1) flow at opening pressure was lower in the male than in the female; (2) the opening pressure was increased by ovariectomy; (3) phenylephrine and KCl stimulated a greater response in the male than in the female, whereas the response to bethanechol was significantly lower in the male than in the female; (4) the male had the greatest resistance to flow among all the groups; and (5) ovariectomy increased the resistance to flow and estrogen treatment reversed the effect of ovariectomy. In conclusion, ovariectomy had significant effects on urethral function that were reversed by estrogen therapy but not by progesterone therapy.

Adrenergic alpha-Agonists↗
PubMed1996

Protective effect of Tadenan on bladder function secondary to partial outlet obstruction.

PURPOSE: Tadenan (DEBAT, Paris, France) is a pharmaceutical agent used in the treatment of benign prostatic hyperplasia (BPH). The specific aim of this study was to determine if pretreatment of rabbits with Tadenan reduced either the hypertrophic response of the bladder to partial outlet obstruction or the accompanying contractile dysfunction. MATERIALS AND METHODS: Twenty-five male New Zealand rabbits (3 to 5 kg.) were separated into 5 groups of 5 rabbits each. Each rabbit in groups 1,2, and 3 received Tadenan orally at 1, 10 and 100 mg./kg./day for 3 weeks. Group 4 received vehicle only (peanut oil); Group 5 were controls. The bladders were evaluated (in vitro studies) after 2 weeks of obstruction. RESULTS: 1) Tadenan did not reduce the effect of partial outlet obstruction on bladder mass. 2) Tadenan pretreatment resulted in a significant protective effect on the contractile responses to field stimulation, bethanechol and KCl. CONCLUSIONS: These results clearly demonstrate that Tadenan pretreatment protected the bladder from the contractile dysfunctions induced by partial outlet obstruction.

Adenosine Triphosphate↗
PubMed1996

[Cognitive neuroanatomy of language: contribution of functional cerebral imaging].

This review summarizes the main results obtained to date, concerning the issue of brain/language relationships, from studies using the modern techniques of in vivo functional imaging of the brain, namely Positron Emission Tomography (PET) and, to a lesser extent, the still experimental method of functional Magnetic Resonance Imaging. These studies mostly rely on the so-called cognitive activation paradigm, which consists of recording blood flow variations as measured in PET in normal volunteers during various linguistic tasks compared to reference tasks. Since the late 80's, a great deal of literature has been accumulating, including studies of various aspects of language functions: perceptual (auditory and visual) processing of linguistic materials, expression, verbal memory, semantics... The first few results obtained have already led to challenge some previously widely held dogmas, derived from classical anatomo-clinical studies, such as the role of Wernicke's area in verbal comprehension and the role of Broca's area in language production. The involvement of the left supramarginal gyrus in some aspects of phonological processing has been directly demonstrated. At the same time, some studies have yielded unexpected results suggesting, for instance, a special role for the inferior lateral parts of the left frontal lobe in semantic and/or voluntary aspects of language processing and episodic verbal memory. Among other studies, those concerning the mechanisms of verbal short-term memory have provided interesting parallels with cognitive models. The demonstration, under certain experimental conditions, of an involvement of hitherto unsuspected cortical regions (such as the insular or the temporopolar cortices) is of potential considerable importance. Finally, with current technical improvements of the imaging methods, it will be shortly possible to take into account the important issue of interindividual variations as well as to perform activation studies in brain-damaged patients.

Brain↗
PubMed1995

Diverging asymmetries of temporo-parietal cortical areas: a reappraisal of Geschwind/Galaburda theory.

The general theory on the biological foundations of cerebral dominance formulated in 1985 by Geschwind and Galaburda entirely relies on a postulated causal relationship between anatomical asymmetry of the planum temporale and functional lateralization of the human brain, but does not take into account asymmetry of another cortical region, the parietal operculum. In 40 normal volunteers whose handedness was specified by the Edinburgh Handedness Inventory, we assessed asymmetries of these two regions on MRI sagittal scans. For both measurements, a significantly larger leftward asymmetry was found in the 24 consistent right-handers compared to the 16 non-right-handers. Moreover, the combination, for each subject, of the two indices of asymmetry, yielded four different subtypes between which handedness distribution significantly differed. We conclude that planum temporale and parietal operculum asymmetries may be divergent and that their convergence is strongly associated with right-handedness. Functional and developmental implications of these findings are discussed by reference to the Geschwind/Galaburda theory.

Adolescent↗
PubMed1995

Mutism and auditory agnosia due to bilateral insular damage--role of the insula in human communication.

We report a case of transient mutism and persistent auditory agnosia due to two successive ischemic infarcts mainly involving the insular cortex on both hemispheres. During the 'mutic' period, which lasted about 1 month, the patient did not respond to any auditory stimuli and made no effort to communicate. On follow-up examinations, language competences had re-appeared almost intact, but a massive auditory agnosia for non-verbal sounds was observed. From close inspection of lesion site, as determined with brain resonance imaging, and from a study of auditory evoked potentials, it is concluded that bilateral insular damage was crucial to both expressive and receptive components of the syndrome. The role of the insula in verbal and non-verbal communication is discussed in the light of anatomical descriptions of the pattern of connectivity of the insular cortex.

Adult↗
PubMed1995

The timing of breastfeeding initiation and its correlates in a cohort of rural Egyptian infants.

Recent data on the patterns and correlates of the timing of breastfeeding initiation in newborns are scanty for many countries including Egypt. To obtain such data in four villages in rural Bilbeis, we recruited apparently healthy, single neonates and their apparently healthy mothers within 4 days of child birth, and followed them prospectively during 1987 through 1989. All 150 neonates included in the analyses were breastfed for some duration. At the time of the first breastfeed, 36, 37, and 27 per cent of the neonates were aged < 2, 2-5, and > or = 6 hours, respectively. All neonates had received the first breastfeed by age 72 hours. In a multivariate, polytomous logistic regression model, modern birth attendants and longer ( > 8 hours) duration of labour were significantly associated with deferment of breastfeeding initiation till the neonate was aged > or = 6 hours. Breastfeeding initiation appeared to be unduly delayed in our study mothers and infants given that they were apparently healthy during the early post-partum period. Later initiation of breastfeeding was associated with indiscriminate prelacteal feeding, earlier termination of breastfeeding, and unwelcome supplementation practices. Our findings emphasize the need to initiate and/or strengthen programmes to promote appropriate breastfeeding practices in Bilbeis and other comparable areas.

Breast Feeding↗
PubMed1995

Functional magnetic resonance imaging at 1.5 T during sensorimotor and cognitive task.

Functional activations of the human brain cortex were observed with a standard 1.5-tesla MR imaging system using a long time echo fast low-angle shot sequence. Neural activation increases regional cerebral blood flow resulting in increased capillaries and venous blood oxygenation. Processing requires adapted algorithms because the time course of intensity signal showed fluctuations of the baseline. The use of a 'follow-up' method to generate activation maps is proposed. Brain activation was detected in striate cortex during photic stimulation and in sensorimotor areas while subjects were moving their hands. In mental imagery tasks, we observed a primary and secondary visual cortex activation during memory recall of the flashing light. Motor ideation showed an activation of the rolandic areas.

Adult↗
PubMed1995

Risk factors for development of first symptomatic Giardia infection among infants of a birth cohort in rural Egypt.

Giardia infection is associated with diarrheal diseases among infants and young children in both industrialized and developing countries. A study was conducted to demonstrate the predisposing factors for occurrence of the first symptomatic Giardia infection among infants in rural Egypt. The study cohort was followed from birth through the first year of life. Univariate and multivariate analyses of data revealed that infants less than six months of age were at special risk for developing their first symptomatic infection compared with infants more than six months of age. Analysis of the data, furthermore, revealed an increased risk of infant Giardia infection associated with living in a household without a latrine (relative risk [RR] = 2.63, confidence interval [CI] = 1.4-4.9, P < 0.05), a mud floor in the sleeping rooms (RR = 1.79, CI = 1.O30-3.0, P < 0.05), and household exposure to more than 10 chickens (RR = 2.5, CI = 1.13-5.56, P < 0.05). In contrast, the mother's education beyond the primary level (RR = 0.28, CI = 0.09-0.85, P < 0.05), drinking water stored in metallic containers (RR = 0.33, CI = 0.11-0.98, P < 0.05), and male sex (RR = 0.52, CI = 0.3-0.89, P < 0.05) were associated with decreased risk of Giardia infection. These data suggest that in addition to age of infants, poverty, low education, gender discrimination, and certain environmental conditions potentiated the risk for developing the first symptomatic infection.

Animals↗
PubMed1995

[Characterization of gestural disorders in primary progressive apraxia: diagnostic and nosographic contribution].

Five cases are reported of patients with so-called primary progressive apraxia, defined as a slowly worsening disturbance of gestural abilities, without other major cognitive changes during a long period, in relation to degenerative cortical atrophy. All five cases, as other cases in the literature, share the following common features: 1) asymmetrical onset of upper limb clumsiness, more often involving the left side, later involving the contralateral side and lower limbs; 2) after a variable delay, the occurrence of symptoms suggesting subcortical involvement (akinesia, limb stiffness, various kinds of movement disorders, dystonia, paresis of vertical gaze); 3) diffuse cortical atrophy typically more pronounced in the superior parietal cortex opposite to the first side affected. The unusual nature of apraxia in all these cases is pointed out and referred to as Luria's "kinesthaesic apraxia", ascribed to a loss of "selectivity" of distal elementary movements. This pattern of symptoms and their specific outcome could represent a distinct entity.

Aged↗
PubMed1994

Covert processing of information in hemianesthesia: a case report.

A 69-year-old patient with a cortical lesion of the primary sensory area showed a surprising sensorimotor control of the anesthetized arm. This observation suggested the existence of residual capacities of somesthetic information processing. This hypothesis was tested using a forced choice procedure on four tasks involving discrimination between different characteristics of the tactual-kinaesthetic stimulus. Whereas the patient was unable to identify the direction of movement or to discriminate between different letters, she could detect the occurrence of the stimulation or its dynamic quality significantly well. These results are discussed in reference to an anatomo-functional organization analogous to the one underlying the processing of visual information.

Aged↗
PubMed1994

Breast-feeding in Egypt.

Planning, implementation and evaluation of programmes to promote appropriate infant feeding practices require detailed, current information about these practices in the target populations. To estimate the prevalences and identify the correlates of overall breast-feeding and of exclusive breast-feeding in different age periods during infancy, a cohort of 152 apparently healthy neonates and their mothers were followed during October 1987 through April 1989 in rural Bilbeis, Sharqiya Governorate, Egypt. Feeding data were collected through twice weekly home visits thus reducing the potential for bias in our findings due to respondent recall errors. The prevalence of overall breastfeeding in the infants declined from 100% in age period 0-11 weeks to 89% in age period 36-47 weeks. Mothers with previous living children were associated with significantly higher (odds ratio [OR]: 6.53, 95% confidence interval [CI]: 1.33-32.09) and ownership of refrigerators was associated with significantly lower (OR: 0.18, 95% CI: 0.05-0.67) overall breast-feeding prevalences in age periods 24-35 and 36-47 weeks, respectively. The prevalence of exclusive breast-feeding in breast-fed infants dropped from 20% in age period 0-11 weeks to 0% in age period 36-47 weeks. After multivariate adjustment, prelacteal feeding was significantly negatively (OR: 0.12, 95% CI: 0.04-0.37) associated with exclusive breast-feeding in age period 0-11 weeks. Nearly 90% of Bilbeis infants were breast-fed at age 47 weeks, but the initiation of supplementation at 0-11 weeks in 80% of breast-fed infants is contrary to current recommendations.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Input respiratory impedance to estimate airway hyperreactivity in children: standard method versus head generator.

We previously found that a significant underestimation of respiratory mechanical impedance (Zrs) at high frequency may result from the upper airway artefact in children, when pressure is directly varied at the mouth. To determine the importance of this artefact in estimating lung response to bronchomotor agents with the forced oscillation technique, input respiratory mechanical impedance was measured using 6-32 Hz pseudorandom pressure oscillations applied directly to the mouth (standard generator (SG)) and around the subject's head (head generator (HG)) in 35 children aged 2.5-13 yrs. Changes in resistance were generally larger with HG than SG. The mean +/- SEM changes in resistance of the respiratory system (Rrs) at 20 Hz induced by acetylcholine or allergen challenge were 15 +/- 4% for SG and 67 +/- 12% for HG, and changes induced by bronchodilators were -25 +/- 2% for SG, and -46 +/- 4% for HG (p < 0.01). Challenge induced negative frequency dependence of Rrs with SG and positive frequency dependence with HG. There was significant increase in inertance after salbutamol with SG, but no significant change occurred with HG. With both methods, respiratory compliance decreased significantly after challenge. Computer simulations showed that the difference in change in Rrs induced by airway challenge with HG and SG could be explained by the effect of the upper airway wall impedance (Zuaw). Zuaw could also account for the change in inertance and compliance observed with SG, but not for the change in compliance with HG. The latter could be reproduced by simulating unequal distribution of mechanical time constants within the lung, increased peripheral lung resistance with compliant central airways.(ABSTRACT TRUNCATED AT 250 WORDS)

Airway Resistance↗
PubMed1994

[Functional cerebral neuro-imaging at 1.5 Tesla. The results of visual, sensorimotor and auditory stimulations].

Functional activation of the cerebral cortex can be observed with a standard 1.5 Tesla MRI magnet. We used a repeated FLASH 2D one-section sequence with a long echo (TE = 60 ms) and a small passing band. Modification of regional cerebral oxygenation due to neurone activation seems to be the main source of contrast. Sensorimotor stimulation was effected by an unusual mobilization of the fingers. Visual stimulation was performed by intermittent lightings at a frequency of 8 Hz. Auditory stimulation relied on listening to speech sounds. Signal increases were localized on the cerebral cortex with precise anatomico-functional correlation. Using a clinical 1.5 Tesla magnet requires an adequate treatment of data. Thus, stimulated cerebral activity can be portrayed by MRI therapy opening a new way for anatomico-functional cerebral studies.

Acoustic Stimulation↗
PubMed1993

Functional and magnetic resonance imaging correlates of callosal involvement in multiple sclerosis.

To investigate functional and anatomical features of callosal involvement in multiple sclerosis (MS), performances of 90 patients with definite MS and 25 matched normal control subjects were compared on three tasks exploring interhemispheric transfer of auditory, sensory, and motor information: a verbal dichotic listening task, a crossed tactile finger localization task, and an alternate finger tapping task. Each patient also underwent a magnetic resonance imaging (MRI) scan (1) to appreciate the extent of white-matter changes by a semiquantitative evaluation of hemispheric brain MRI hyperintensities and (2) to measure the degree of total and regional callosal atrophy using an automatized method of partition of the midsagittal callosal area. Interhemispheric transfer and/or integration was impaired in patients with MS for all modalities explored and proportional to both degree of callosal atrophy and diffusion of white-matter lesions. Moreover, in good agreement with data obtained from partial commissurotomy studies, performance on each functional task was predominantly associated with atrophy of one part of the callosum, namely left-ear dichotic suppression with the posterior callosal region, alternate finger tapping with the anterior region, and cross-localization with midanterior and posterior regions. Finally, a subgroup of patients without MRI white-matter hyperintensities also showed significant impairment of callosal function and relative atrophy of the callosum. These findings suggest the potential clinical value of callosal involvement in MS and the usefulness of MS as a model of interhemispheric disconnection.

Adolescent↗
PubMed1993

Non palpable breast carcinomas. Histological and immunohistochemical studies of 160 cases.

A series of 160 impalpable breast carcinomas was collected from 1979 to 1991. Mammographs showed microcalcifications (64%), or opaque images (36%). Surgical specimens were X-rayed during the intervention in order (i) to ascertain that the lesions detected on mammographs were removed, and (ii) to guide the pathologist in sampling tissue fragment for an appropriate microscopic evaluation of the lesions. During the intervention, the peroperation histological diagnosis was correct in 63% of the cases, whereas malignancies were underscored in 37%. No false positive diagnosis was recorded. A large majority (92%) of false diagnoses stated during surgery were in situ carcinomas diagnosed as epitheliosis and invasive carcinomas diagnosed as in situ carcinomas. In 63% of the cases the axillary lymph node could be removed during the first intervention. In 91% of the cases "in sano" margins of resection were evaluated as such during the intervention. The size of tumors ranged from 1 to 60 mm (m = 10 mm - SD = 8.45), 70% measuring less than 10 mm. Carcinomas were in situ (23.75%), microinvasive (13.75%) and invasive (62.5%). Carcinomas were ductal (78.1%), lobular (18.7%) and of other types (14.2%). A majority of intraductal carcinoma (68%) were comedocarcinomas. Invasive carcinomas accounted for grade I in 37% of the cases, grade II in 56%, grade III in 7%, ductal carcinomas and for tubular carcinomas in 15%. Immunodetection could be performed on frozen sections in 78 cases. Tumors were receptor positive in 58% of the cases. The greater growth fraction (Ki-67) and higher detection of HER-2/neu oncogene product were observed in comedocarcinomas. Diploid tumors accounted for 52% of those evaluated (n = 48).

Adult↗
PubMed1993

Paroxysmal pruritus and multiple sclerosis.

We report a patient who presented with paroxysmal pruritus in association with multiple sclerosis. Magnetic resonance imaging of the cervical spinal cord showed a lesion at a level corresponding to the dermatomal location of the pruritus.

Acute Disease↗
PubMed1993

Community-based prevalence profile of arboviral, rickettsial, and Hantaan-like viral antibody in the Nile River Delta of Egypt.

To determine the current prevalence of antibody to arboviruses, rickettsiae, and hantaan-like viruses, a survey was carried out in the Nile River Valley of Egypt, one of the principal foci of the 1977-1978 Rift Valley fever (RVF) outbreak. Blood specimens were obtained from 915 persons representing 190 study households. Enzyme immunoassay testing showed that the overall prevalence of IgG antibody was 4% to sand fly fever Sicilian (SFS), 2% to sandfly fever Naples (SFN), 15% to RVF, 20% to West Nile, and 4% to Hantaan (HTN) viruses. Antibody was demonstrated among 32% of the same study subjects to Coxiella burnetii, 58% to Rickettsia typhi, and 32% to R. conorii. The prevalence of agent-specific antibody tended to increase with age. Particularly notable was the low prevalence of RVF infection in children born after the height of the RVF outbreak. No detectable antibodies were found in the population less than seven years of age and in only 3% of those 7-12 years old. In contrast, 26% of the study population 13-19 years old, who were young children and infants at the time of the outbreak, were found to have RVF antibodies, suggesting that the level of intensity associated with transmission decreased considerably following the documented 1977-1978 outbreak. Geometric mean titers (GMT) ranged from 139 for C. burnetii to 1,305 for RVF, and did not vary significantly by age, except for high titers for RVF in the 20-49-year-old age group. A significant upward trend in GMT was also noted when antibody was detected in the specimen for more than one phlebovirus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗