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S Haddad

Publications and source records attributed to S Haddad.

At least 55 records · Page 3Linked to original sources
PubMed1998

Low-intensity ultrasound energy applied to the testes of aged rats.

Previous studies from our laboratory have shown that low-intensity ultrasound applied to the scrotum of prepubertal rats causes a 62% increase in plasma testosterone, suggesting a possible stimulation of LH receptors and/or the enzymes controlling the steroidogenic process. The purpose of the present study was to investigate whether low-intensity ultrasound has a stimulatory effect on the androgenic activity of aged testes. In addition to plasma testosterone, LH and FSH, the testicular spermatogenic status was also analysed. Ultrasound applied to the scrotum of aged rats did not stimulate sperm production, which was significantly reduced compared to sexually mature animals, and failed to re-establish the steroidogenic testicular function, which was decreased by 74%, suggesting an inherent loss of gonadal steroidogenic competence.

Aging↗
PubMed1997

Effect of citrate on growth of Lactococcus lactis subsp. lactis in milk.

The effect of citrate on the growth of Lactococcus lactis subsp. lactis var. diacetylactis in milk has been investigated. Five strains of Lactococcus lactis subsp. lactis var. diacetylactis were compared to their citrate-negative variants, which lack the plasmid coding for citrate permease. In most cases, acidification kinetics and the final bacterial concentration of pure cultures of parental and variant strains did not differ significantly. Co-cultures of parental and variant strains, however, systematically tended towards the predominance of parental strains. Citrate metabolism is responsible for this change, since the predominance of citrate-positive strains was not observed in the absence of citrate. Continuous culture in milk enabled the difference in growth rates between the parental strain Lactococcus lactis subsp. lactis var. diacetylactis CDI1 and its citrate-negative variant to be quantified by following changes in the populations of the two co-cultured strains. At 26 degrees C, the growth rate of the parental strain was 7% higher than that of its citrate-negative variant. These results show that citrate metabolism slightly stimulates the growth of lactococci in milk.

Animals↗
PubMed1997

Isolated brain metastases of osteosarcoma in a patient presenting with a patent foramen ovale.

We report the case of a patient in whom brain MR imaging was requested for initial symptoms of intracranial hypertension. The presence of multiple intracranial hemorrhagic lesions suggested brain metastases. Body screening showed periosteal osteosarcoma of the left fibula with no lung metastases, but with a patent foramen ovale which probably allowed neoplastic cells to reach the brain without being filtered through the lungs. The conclusion of this study was that a left-right cardiac communication is to be considered in cases of isolated brain metastases from osteosarcoma.

Bone Neoplasms↗
PubMed1997

Ultrasound stimulation of rat testes damaged by busulfan.

The purpose of the present study was to investigate whether or not low-intensity ultrasound exposure (20 mW/cm2 average intensity) accelerates the repair of rat germinal epithelium damaged by an antispermatogenic agent. The results from analysis of testicular weight and DNA content, sperm production and epididymal sperm concentration showed that the time needed for the reestablishment of the spermatogenic process following busulfan treatment was not reduced by ultrasound energy suggesting that, in contrast to many other mammalian tissues, the seminiferous epithelium is refractory to ultrasound stimulation.

Alkylating Agents↗
PubMed1997

Rate of pyrene metabolism in rat liver post-mitochondrial fractions.

The objective of the present study was to estimate the maximal velocity (Vmax) and Michaelis affinity constant (Km) for the oxidation of pyrene to 1-hydroxypyrene using rat liver post-mitochondrial fractions. The approach involved the determination of the concentrations of 1-hydroxypyrene formed during 5 min incubations of pyrene (initial concentrations: 0.0025-0.5 microM), and correcting for the rate of 1-hydroxypyrene disappearance (2.16 x 10(-5) per (mg protein/l)/min) during the incubation period. The Vmax and Km for pyrene metabolism in the rat corresponded to 0.0577 +/- 0.0108 micromol/min per g liver and 27.73 +/- 13.54 microM, respectively. The intrinsic clearance (CL(int)) of pyrene in the rat estimated in the present study (0.041-0.111 l/min per kg) was within the range of the previously reported CL(int) in humans (0.037-0.125 l/min per kg). The results of this study suggest that CL(int) of pyrene in humans can be predicted from such data obtained in the rat.

Animals↗
PubMed1997

Tetraamelia associated with a syrinx: fortuitous association or clue?

We report a male infant born at 43 weeks of gestation with tetraamelia. The upper limbs consisted of the presence of very short stumps containing a single bone. The lower limbs were totally absent. There were also a facial hemangioma, mild micrognathia, testis ectopia and osseous malformations. A magnetic resonance imaging exam showed no significant abnormality of the brain but disclosed a cervico-dorso-lumbar syringomyelic cord without any other associated spinal malformation. Teratogenic as well as genetic causes are discussed.

Brain↗
PubMed1997

Do work-place smoking bans cause smokers to smoke "harder"? Results from a naturalistic observational study.

The purpose of this study was to investigate whether smokers outside buildings with work-place smoking bans smoke "harder" than those smoking in social settings. An unobtrusive random observational study of smokers followed by structured interview was used, with 143 smokers taking smoking breaks outside their office buildings and 113 smokers in social settings. The main outcome measurements were number of puffs per cigarette and cigarette smoking duration. The mean number of puffs per cigarette for the office building group was 18.7% greater than that for the social settings group (10.7 +/- 3.2 vs. 8.7 +/- 2.7, t = 5.58, df = 253, p < 0.001); 74.8% of smokers outside offices took more than the mean number of puffs for the group compared to 42.5% of smokers in social settings (chi 2 df 1 = 26.31, p < 0.0001). Mean cigarette smoking duration was 30.4% shorter for the work-place group than the social settings group (3.9 +/- 1.2 minutes vs. 5.6 +/- 2.6 minutes). Of smokers outside offices, 55.2% had a cigarette smoking duration between 3 and 4.59 minutes, while 53.1% of smokers in social settings took > or = 5 minutes to smoke the observed cigarette (chi 2 df 2 = 31.55, p < 0.0001). Smokers who scored at the 75th percentile on the Fagerstrom Tolerance Scale took a mean 9.5 +/- 2.6 puffs per cigarette compared to 9.3 +/- 2.7 puffs by those who scored in the 25th percentile on the scale (t = 0.34, df = 145, p = 0.73). Regardless of degree of nicotine dependency, smokers leaving work-stations to smoke outside buildings smoked their cigarettes nearly 19% "harder" than cigarettes smoked in social settings. The individual and public health benefits of reduced smoking frequency engendered by work-place smoking bans may be lessened by policies which allow smokers to take smoking breaks.

Adult↗
PubMed1997

[Imaging aspect of a case of fibrodysplasia ossificans progressiva].

Fibrodysplasia ossificans progressiva is a rare congenital disease that affects children under the age of five years. Soft tissue swelling of the cervical and dorsal regions with local pain, warmth and low grade fever are the early clinical manifestations, usually associated with hallux valgus and microdactily of the fingers and toes. Calcifications of the fascias and muscles cause muscular contractures leading to progressive disability and restrictive lung disease. In the early stage, CT shows edema of the soft tissues and later on, calcifications of muscular fascia. The association of these radiographic and CT findings is specific and should avoid muscular biopsies which are known to be an aggravating factor in this disease.

Calcinosis↗
PubMed1997

[A rare cause of diplopia: a sinus cavernous dural fistula. A case report].

Dural fistulas of the cavernous sinus represent a relatively unknown etiology for diplopia. The authors report on a case where combination of MR and transcranial Doppler (especially transocular) helped in diagnostic and therapeutic approach. They propose a new algorithm for the management of diplopia.

Arteriovenous Fistula↗
PubMed1997

[Digestive manifestations of hereditary angioneurotic edema. Apropos of a case].

We present a case of hereditary angioedema with cutaneous and intestinal manifestations mimicking a small bowel tumor on computed tomography, and in which unnecessary surgery was avoided by follow-up computed tomography. We discuss the pathophysiology, clinical and radiological manifestations of the disease, as well as its computed tomographic appearance.

Adult↗
PubMed1997

[MRI in the diagnosis of osteoid osteoma].

INTRODUCTION: Osteoid osteoma (OO) is a frequently encountered benign bone tumor, seen in young adults with male predominance. MATERIALS AND METHODS: Nine patients complaining of nonspecific extremity pain underwent MRI examination. The sequences obtained were T1 and T2 weighted spin-echo and T2 weighted gradient echo. A CT scan examination followed in all cases, exploring the region of the abnormal signal seen on MRI. The results of both examinations were compared. RESULTS: In six of the nine patients (66.6%) MRI showed evidence suggestive of osteoid osteoma, comparable that seen on CT scan. In three patients (33.3%), MRI showed a nonspecific and ill-defined bone marrow signal abnormality. CT cuts focused on those areas of signal abnormality showed the nidus. DISCUSSION: MRI is more sensitive than CT scan in detecting soft tissue and bone marrow abnormalities adjacent to an osteoid osteoma. This may produce a misleading aggressive appearance on MR images. CT scanning is more specific than MRI, by showing the nidus. In three patients studied, the nidus was only seen by CT, the other six osteoid osteomas were equally seen by CT and by MRI. In our study, MRI revealed abnormalities in all the cases. It was also highly specific for osteoid osteoma in 66.6%. CONCLUSION: MRI is very sensitive in detecting bone marrow and soft tissue abnormalities, and can suggest the diagnosis of OO in a good number of patients. In the remainder cases MRI guides the CT-scan. CT is more accurate and remains the definite examination for the diagnosis of OO, by showing the nidus.

Adolescent↗
PubMed1997

[The effects of aerobic physical training of short duration using upper limbs in paraplegic persons with mild hypertension].

PURPOSE: To study the modifications induced by physical training (PT) using upper limbs in aerobic condition of short duration on cardiovascular and metabolic variables. METHODS: Eleven paraplegic persons, with a mean age of 59 years, 7 men and 4 women with lesions at T9 through T11 and mild hypertension (HAS) were studied. The patients were studied before and after 12 weeks of a supervised program of PT, through exercise tests in a mechanic ergometer (ST) adapted for the arms. We employed an intermittent protocol with stress increments of 125 (20w) and 140 kgm/min (25w) for women and men, respectively every 3 min. The ergometric speed ranged from 83 to 95 rpm. The oxygen consumption (VO2) was estimated according to American College of Sports Medicine equation for arms. The exercise intensity during the TF program was estimated through the Karvonen cardiac frequency reserve, with a variation of 65% to 85% and the Borg stress scale of subjective perception during the stress test. RESULTS: The mean maximal aerobic capacity increased in 22% (930 +/- 349 vs 1138 +/- 290 mL/min; p = 0.003); there was a reduction of systolic and diastolic pressures at rest and after submaximal exercise of 4%, 15% and 5% and 5%, respectively. CONCLUSION: Physical training of mild to moderate intensity using the upper limbs in paraplegic persons, besides inducing functional capacity increment, is an important model of non drug control of the hypertensive response.

Arm↗
PubMed1997

["Mirror" intracavernous aneurysms. Therapeutic dilemma apropos of a case with review of the literature].

"Mirror" cavernous aneurysms are exceptional; only 66 such cases having been published until mid-1996. We report on a 68-year-old woman who presented for left exophthalmos, diplopia and neuralgia. MR and angiography demonstrated a giant symptomatic aneurysm on the left side and an incidental small one on the right side. The patient was treated in two sessions: first, she had selective embolization of her right aneurysm; two weeks later, her left carotid artery was sacrificed with detachable balloons, after a well-tolerated occlusion test. This original and successful approach permitted to achieve a reasonable goal when considering the patient's age, operative morbidity, risk of future complications and final result. A review of the pathophysiology, clinical manifestations and therapeutic indications is presented and discussed.

Aged↗