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S Haddad

Publications and source records attributed to S Haddad.

At least 19 recordsLinked to original sources
PubMed2006

[Difficulties of the management of head and neck neurofibromatosis].

INTRODUCTION: Neurofibromatoses represent a group of 7 diseases having the same cutaneous signs due to a common embryologic origin. The types 1 and 2 are the most frequent and the most studied. Neurofibromatosis type 1 (NF1) or Von Recklinghausen's neurofibromatosis is an autosomal dominantly inherited disease, whose prevalence is 1/4500. The cranio-orbitotemporal lesions exist in 1 to 10% of the cases. Neurofibromatosis type 2 (NF2) is also an autosomal dominantly inherited disease, but is ten times less frequent than the NF1 and is characterized by bilateral vestibular schwannomas (former acoustic neurinomas). The purpose of this work was to detail the clinical features, highlighting the diagnostic and therapeutic difficulties. MATERIAL AND METHODS: Nine patients managed between 1990 and 2005 were reviewed retrospectively. Eight patients were found carrier of NF1 and one patient carrier of NF2 according to the diagnostic criteria of the 1988's National Institute of Health consensus. RESULTS: Five women and four men were managed; patient age varied between 13 and 62 years and the mean age was 26 years. Surgical resection of the tumor was carried out among 8 patients with bone reconstruction of the orbit on 3 patients and cutaneous expansion on one other. The results are difficult to appreciate especially that the surgery was iterative. However, all our patients were satisfied with the result and we noted recurrence in a patient presenting a retro-auricular tumor, which filled the external auditory canal requiring a further surgery. The patient having NF2 was treated by neurosurgery and showed a good result. DISCUSSION: The NF1 manifestations are extremely variable. Facial neurofibromatoses are difficult to control given the presence of soft tissues infiltration and the associated osseous dysplasia. The results are modest and recurrence is frequent. Cancer risks and the disease's completely unpredictable evolution urge a regular and multidisciplinary patient follow-up.

Adolescent↗
PubMed2006

[Primary malignant melanoma of the nasal cavity presenting as a large tumor of the cheek].

INTRODUCTION: Malignant melanoma of the nasal cavity is a rare tumor usually causing unilateral nasal obstruction and nasal bleeding. Diagnosis is achieved with immunohistochemistry analysis. Surgery is proposed for curative treatment. CASE REPORT: We report the case of a 60-year-old man with a malignant melanoma of the nasal cavity revealed by an important tumor of the cheek. Epistaxis and nasal obstructive syndrome occurred later. Because of the tumor stage, palliative chemotherapy was performed but the patient died 4 months after the diagnosis. DISCUSSION: This clinical presentation of malignant melanoma of the nasal cavity, related to local spreading, is exceptional. CT scan and MRI are essential for tumor staging and therapeutic decision-making. Prognosis remains poor.

Cheek↗
PubMed2005

[Hypernatremic dehydration in children: retrospective study of 105 cases].

UNLABELLED: The hypernatremic dehydration defined by a serum sodium concentration> or = to 150 mmol/l, is a particular form of acute dehydration and constitutes a medical emergency requiring a prompt and adequate diagnosis and management. PURPOSE: To precise the epidemiological profile, course, causes and therapeutic particularities of hypernatremic dehydration in children. POPULATION AND METHODS: Retrospective review of 105 children admitted in the general Paediatrics department of the Fattouma Bourguiba university hospital in Monastir (Tunisia), for hypernatremic dehydration between January 1st 1990 and December 31 2002. RESULTS: Hypernatremic dehydration represented 11.51% of all kinds of dehydration. The mean age was 6.5 months with a small male predominance. The socio-economic level of the parents was good in 62.8% of cases. Half of the children were in shock. Severe dehydration was present in 87.6% of cases and neurological signs were observed in 77.14% of cases. The initial mean serum sodium concentration was 159 mmol/L. Acidosis and acute renal failure were associated respectively in 97.2% and 76.2% of cases. Prominent cause of hypernatremic dehydration was diarrhoea (94.3%). Intravenous rehydration with 5% glucose solution at the average of 147 ml/kg/day and containing a mean sodium level of 42 mmol/L was performed in 74% of cases. In most cases (84.1%) serum sodium was normalized within the first 72 hours. Complications were noted in 5.7% of cases and mortality rate was 11.4%. CONCLUSION: Hypernatremic dehydration was common in infant and the prominent cause is still dominated by diarrhoea in our country. The management of hypernatremic dehydration is based on oral or intravenous rehydration and plasma expanding fluids when shock is present or imminent. The serum sodium concentration should be gradually corrected and should not exceed 0.5 mmol/L/h. Prevention is based on the pursuit of breastfeeding and the use of oral rehydration solution in infantile diarrhoeas.

Dehydration↗
PubMed2005

The peroxisome proliferator activated receptorgamma2 (PPARgamma2) Pro12Ala variant: lack of association with type 2 diabetes in obese and non obese Tunisian patients.

OBJECTIVES: Peroxisome proliferator activated receptorgamma2 (PPARgamma2) is a nuclear receptor that regulates adipocyte differentiation, lipid metabolism and probably insulin sensitivity. There have been several reports on the relationship between the PPARgamma2 Pro12Ala genotype and the development of obesity or type 2 diabetes. We designed a case-controlled study to investigate the potential association of the genetic variation of the PPARgamma2 gene with type 2 diabetes in Tunisians. METHODS: We used the polymerase chain reaction and restriction enzyme digestion to characterize the variation of the Pro12Ala polymorphism of the PPARgamma2 gene in 242 unrelated Tunisian patients with type 2 diabetes and 246 healthy control subjects. RESULTS: Analysis of the Pro12Ala polymorphism of the PPARgamma2 gene in patients with type 2 diabetes and in control subjects revealed no significant differences in the PPARgamma2 allele frequencies between diabetic patients and control subjects. However the PPARgamma2 Ala12 allele was found significantly associated with a high level of systolic blood pressure in diabetic patients. Stratification of diabetic patients on obese and non obese subjects showed non significant differences in the PPARgamma2 Ala12 frequency between the two groups. CONCLUSION: These results suggest that the PPARgamma2 gene is unlikely a major gene for type 2 diabetes mellitus or obesity in Tunisian subjects.

Amino Acid Substitution↗
PubMed2004

Polymorphism of stress protein HSP70-2 gene in Tunisians: susceptibility implications in type 2 diabetes and obesity.

OBJECTIVES: Tumor necrosis factor alpha (TNFalpha) is expressed primarily in adipocytes and elevated levels of this cytokine have been linked to obesity and insulin resistance. Several studies have shown statistical evidence of linkage between obesity and the chromosomal region encompassing the TNFalpha gene, suggesting that TNF alpha and/or a nearby gene is involved in the pathogenesis of obesity. Recently we analyzed the -308 TNFalpha polymorphism and that of HSP70-2 gene in Tunisian patients with obesity and no significant difference in allele frequencies of the -308 TNFalpha polymorphism was found between obese patients and controls. In contrast, polymorphism in HSP70-2 gene was found to be highly associated with obesity. Both TNFalpha and HSP70-2 genes have been mapped within the major histocompatibility complex (MHC). We designated a case-controlled study to investigate a potential association of genetic variation of the TNFalpha and that of the heat shock protein 70-2 (HSP70-2) with type 2 diabetes. METHODS: We used the polymerase chain reaction and restriction enzyme to characterize the variation of the TNFalpha promoter region and that of the HSP70-2 gene in 280 unrelated Tunisian patients with type2 diabetes and 274 healthy control subjects. RESULTS: Analysis of the -308 TNFalpha polymorphism in patients with type 2 diabetes and in control subjects revealed that the heterozygous TNF1/TNF2 genotype was significantly less frequent in the patient group (p=0.003), suggesting that TNF1/TNF2 may be considered as a protective marker against type 2 diabetes (OR=0.58). In contrast, a significant relative risk of type 2 diabetes was found associated with the P2-HSP70-2 homozygous genotype in non obese diabetic subjects (OR=1.97; p=0.0012). CONCLUSION: These results along with those showing high frequency of P2-HSP70-2 genotype in obese Tunisians, suggest that HSP70-2 polymorphism has susceptibility implications in both obesity and diabetes.

Blood Glucose↗
PubMed2004

Detection of Pneumocystis jiroveci in respiratory specimens by four staining methods.

We examined four staining methods on replicate smears of 313 respiratory specimens submitted for Pneumocystis jiroveci examination. The sensitivity and specificity of Calcofluor white stain (CW) were 73.8 and 99.6%, respectively. The sensitivity and specificity of Grocott-Gomori methenamine silver stain (GMS) were 79.4 and 99.2%, respectively. The sensitivity and specificity of Diff-Quik stain were 49.2 and 99.6%, respectively. The sensitivity and specificity of Merifluor Pneumocystis stain were 90.8 and 81.9%, respectively. Only CW and GMS had positive and negative predictive values of >90%.

Bronchoalveolar Lavage Fluid↗
PubMed2003

Cystic echinococcosis in Algeria: cattle act as reservoirs of a sheep strain and may contribute to human contamination.

In Algeria, cystic echinococcosis (CE) is a serious economic and public health problem. The common sheep/dog cycle is usually considered as the major source of human contamination. But to date the main strain of Echinococcus granulosus involved in the human contamination and the role of other hosts are still unknown. This paper reports an original work performed in northern Algeria combining field observations and molecular analysis. In a first step, examination of 6237 carcasses in slaughterhouses showed high infection and fertility rates in cattle and dromedaries. Then, in a second step, we used a molecular biology approach to identify the E. granulosus strain(s) involved. Forty-six samples from various origins were collected. They were analysed using comparison of PCR-amplified DNA sequences with one genomic (BG 1/3) and two mitochondrial (COI and NDI) targets. Results show the presence of a "sheep" strain of E. granulosus in North Algeria circulating between cattle and ovines and infectious to humans, whereas in South Algeria, a "camel" strain and a "sheep" strain were found to circulate in camels and in sheep, respectively. This study also reports an ambiguous genotype which resembled the "sheep" strain genotype (Gl) on the basis of the partial COI gene sequence, whereas on the basis of the partial NDI gene sequence, it was similar either to the "sheep" strain (Gl) or to the "camel" strain (G6). Besides its basic interest, our study confirms the role of other hosts (mainly cattle) in leading to transmission to humans and suggests that control measures should not only target sheep.

Algeria↗
PubMed2002

Competing phases in the high field phase diagram of (TMTSF)(2)ClO(4).

A model is presented for the high field phase diagram of (TMTSF)(2)ClO(4), taking into account the anion ordering, which splits the Fermi surface into two bands. For strong enough field, the largest metal spin density wave critical temperature corresponds to the N=0 phase, which originates from two intraband nesting processes. At lower temperature, the competition between these processes puts at disadvantage the N=0 phase vs the N=1 phase, which is due to interband nesting. A first order transition then takes place from the N=0 to N=1 phase. We ascribe to this effect the experimentally observed phase diagrams.

Journal Article↗
PubMed2002

Normal cardiac flow velocities at 14-16 weeks of gestation measured by transvaginal ultrasound.

OBJECTIVE: Doppler ultrasound has been used to study the flow velocities through the valves and arteries of the fetal heart. Using transvaginal sonography, we sought to determine normal values for flow velocities through the fetal heart valves at 14-16 weeks of gestation. METHODS: Eighty-seven normal fetuses were examined. The flow velocity waveforms were visualized using Doppler ultrasound with the sample volume calipers placed just distally to the four fetal valves. Peak E- and A-wave velocities were recorded for the tricuspid and mitral valves and peak systolic flow velocities were recorded for the ascending aorta and pulmonary arteries. Linear regression for comparison of flow velocities with gestational age was performed. RESULTS: There was no significant correlation between any of the velocities and gestational age. CONCLUSIONS: Flow velocities through the fetal cardiac valves remain unchanged at 14-16 weeks of gestation as measured by transvaginal Doppler sonography.

Coronary Circulation↗
PubMed2002

Perceived quality of care of primary health care services in Burkina Faso.

INTRODUCTION: Patients' views are being given more and more importance in policy-making. Understanding populations' perceptions of quality of care is critical to developing measures to increase the utilization of primary health care services. OBJECTIVE: Documentation of user's opinion on the quality of care of primary health care services. METHODS: A 20-item scale, including four sub-scales related to health personnel practices and conduct, adequacy of resources and services, health care delivery, and financial and physical accessibility, was administered to 1081 users of 11 health care centres in the health district of Nouna, in rural Burkina Faso. RESULTS: The respondents were relatively positive on items related to health personnel practices and conduct and to health care delivery, but less so on items related to adequacy of resources and services and to financial and physical accessibility. In particular, the availability of drugs for all diseases on the spot, the adequacy of rooms and equipment in the facilities, the costs of care and the access to credit were valued poorly. Overall, the urban hospital was rated poorer than the average rural health care centre. Analysis of variance showed that, overall, health system characteristics explain 29% of all variation of the responses. CONCLUSION: Improving drug availability and financial accessibility to health services have been identified as the two main priorities for health policy action. Policy-makers should respect these patient preferences to deliver effective improvement of the quality of care as a potential means to increase utilization of health care.

Burkina Faso↗
PubMed2001

Characterization of age-related changes in body weight and organ weights from birth to adolescence in humans.

The pharmacokinetics and tissue dose of chemicals may differ among individuals of a population, particularly between adults and children. The adult-children differences in pharmacokinetics arise from age-related changes in the physiological, biochemical, and physicochemical determinants of uptake and disposition of chemicals. The objectives of this study were to review the published literature to assemble data on the human body weight and organ weights as a function of age (specifically between birth and 18 yr old) and to analyze these data, in order to develop regression equations for calculating body weight and organ weights of children using age as the dependent function. The specific organs/tissues for which the data on age-related weight were obtained and analyzed include blood, adipose tissues, liver, lungs, brains, heart, kidneys, spleen, the reproductive organs (male: prostate gland, seminal vesicle, testes, and epididymis; female: ovaries, uterus, and uterine tubes), glands (adrenal, pituitary, thymus, pancreas, and thyroid), bone marrow (total and red), intestinal tract, stomach, muscle, skin (epidermis and dermis), and skeleton. In both male and female children, the sum of these organs is systematically lower than the body weight, and this discrepancy may be resolved with the additional availability and consideration of data on hypodermis weight. The equations and data on body weight and organ weights presented in this article should be useful for constructing age-specific, physiologically based pharmacokinetic models for children.

Adolescent↗
PubMed2001

Cerebral lateral ventricular atrial diameter of male and female fetuses at 20-24 weeks' gestation.

OBJECTIVE: To determine if the lateral ventricular atrial diameter differs between male and female fetuses at 20-24 weeks' gestation. DESIGN: Prospective study. METHODS: The transverse diameter of the ventricular atrium was measured from inner wall to inner wall for a total of 202 pregnant women with 105 male fetuses and 97 female fetuses. RESULTS: The mean diameter of the ventricular atrium for the 202 fetuses was 4.96 +/- 0.96 mm (range, 2.1-8.4 mm). The 105 males had a mean diameter of 4.95 +/- 0.98 mm and the 97 females a mean diameter of 4.97 +/- 0.94 mm. There was no statistical difference between the sexes. CONCLUSIONS: In our population, there was no difference between ventricular atrial diameter in male and female fetuses at 20-24 weeks' gestation.

Cerebral Ventricles↗
PubMed2001

Loyalty to the regular care provider: patients' and physicians' views.

BACKGROUND: Changes in the organization of primary care practices are likely to have repercussions on the manner in which patients and physicians perceive loyalty to a regular source of care. A better understanding of their views will contribute to conceptual reflections on this poorly documented topic and, where needed, will reinforce efforts to adapt services to patient expectations. OBJECTIVES: The aims of this study are to document and compare the views that patients and GPs have of loyalty to the regular care provider. METHODS: This exploratory study uses the focus group technique. In 1997, we set up three groups of patients and three groups of physicians practising in Montreal. A total of 23 patients and 14 physicians participated in the study. The meetings investigated the participants' points of view on various aspects of the notion of loyalty. Analysis was based on transcripts of the meetings. The emerging themes were identified and the viewpoints were coded independently and then revised (when necessary) in order to obtain a consensus. RESULTS: Patients and physicians have a relatively congruent vision of the notion of loyalty. This tendency to use the regular source of care over time appears to be rooted in a formal or informal contract between patients and their physicians and implies a sustained partnership and a strong interpersonal relationship. The relationship established is neither exclusive nor permanent. Patients periodically reconsider it by evaluating their physician's technical and interpersonal skills. CONCLUSIONS: This study highlights the dynamic and multidimensional nature of the notion of loyalty. It shows that patients clearly identify with a particular physician rather than a clinic. The results challenge the prevailing methods of assessing longitudinality of care.

Adult↗
PubMed2001

A PBPK modeling-based approach to account for interactions in the health risk assessment of chemical mixtures.

The objectives of the present study were: (1) to develop a risk assessment methodology for chemical mixtures that accounts for pharmacokinetic interactions among components, and (2) to apply this methodology to assess the health risk associated with occupational inhalation exposure to airborne mixtures of dichloromethane, benzene, toluene, ethylbenzene, and m-xylene. The basis of the proposed risk assessment methodology relates to the characterization of the change in tissue dose metrics (e.g., area under the concentration-time curve for parent chemical in tissues [AUCtissue], maximal concentration of parent chemical or metabolite [Cmax], quantity metabolized over a period of time) in humans, during mixed exposures using PBPK models. For systemic toxicants, an interaction-based hazard index was calculated using data on tissue dose of mixture constituents. Initially, the AUCtarget tissue (AUCtt) corresponding to guideline values (e.g., threshold limit value [TLV]) of individual chemicals were obtained. Then, the AUCtt for each chemical during mixed exposure was obtained using a mixture PBPK model that accounted for the binary and higher order interactions occurring within the mixture. An interaction-based hazard index was then calculated for each toxic effect by summing the ratio of AUCtt obtained during mixed exposure (predefined mixture) and single exposure (TLV). For the carcinogenic constituents of the mixture, an interaction-based response additivity approach was applied. This method consisted of adding the cancer risk for each constituent, calculated as the product of q*tissue dose and AUCtt. The AUCtt during mixture exposures was obtained using an interaction-based PBPK model. The approaches developed in the present study permit, for the first time, the consideration of the impact of multichemical pharmacokinetic interactions at a quantitative level in mixture risk assessments.

Air Pollutants, Occupational↗
PubMed2001

Cloning and expression of the benzoate dioxygenase genes from Rhodococcus sp. strain 19070.

The bopXYZ genes from the gram-positive bacterium Rhodococcus sp. strain 19070 encode a broad-substrate-specific benzoate dioxygenase. Expression of the BopXY terminal oxygenase enabled Escherichia coli to convert benzoate or anthranilate (2-aminobenzoate) to a nonaromatic cis-diol or catechol, respectively. This expression system also rapidly transformed m-toluate (3-methylbenzoate) to an unidentified product. In contrast, 2-chlorobenzoate was not a good substrate. The BopXYZ dioxygenase was homologous to the chromosomally encoded benzoate dioxygenase (BenABC) and the plasmid-encoded toluate dioxygenase (XylXYZ) of gram-negative acinetobacters and pseudomonads. Pulsed-field gel electrophoresis failed to identify any plasmid in Rhodococcus sp. strain 19070. Catechol 1,2- and 2,3-dioxygenase activity indicated that strain 19070 possesses both meta- and ortho-cleavage degradative pathways, which are associated in pseudomonads with the xyl and ben genes, respectively. Open reading frames downstream of bopXYZ, designated bopL and bopK, resembled genes encoding cis-diol dehydrogenases and benzoate transporters, respectively. The bop genes were in the same order as the chromosomal ben genes of P. putida PRS2000. The deduced sequences of BopXY were 50 to 60% identical to the corresponding proteins of benzoate and toluate dioxygenases. The reductase components of these latter dioxygenases, BenC and XylZ, are 201 residues shorter than the deduced BopZ sequence. As predicted from the sequence, expression of BopZ in E. coli yielded an approximately 60-kDa protein whose presence corresponded to increased cytochrome c reductase activity. While the N-terminal region of BopZ was approximately 50% identical in sequence to the entire BenC or XylZ reductases, the C terminus was unlike other known protein sequences.

Benzoates↗