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S Hassid

Publications and source records attributed to S Hassid.

At least 19 recordsLinked to original sources
PubMed2002

Unknown primary detected by FDG-PET. A review of the present indications of FDG-PET in head and neck cancers.

To investigate the indications of 18F-2-fluoro-2-Deoxy-D-glucose (FDG) Positron Emission Tomography (PET) in head and neck cancer, the present study focuses on a case of cervical metastatic lymph node, which is not detected by the routine approach. It discusses the potential role of FDG-PET in the detection of unknown primary tumors, lymph node metastasis and post radiation follow-up, and demonstrates the implications of its findings through a few examples. Based on the literature in the field of head and neck oncology, the paper recommends the following uses for FDG-PET: 1. To guide biopsy or even local resection at the initial stage of examining the unknown primary lesions in case of high clinical suspicion 2. A whole body PET in high-risk patients may prevent unnecessary treatment and reduce the number of examinations 3. To monitor tumor response before full-dose irradiation so as not to delay the salvage surgery when applicable 4. To detect residual, recurrent or secondary neoplasm after definitive radiotherapy at least 4 months post-treatment 5. To revise the necessity of neck treatment in case of a negative PET, in the NO necks; and 6. In cases of clinical suspicion for laryngeal cancer recurrence and absence of objective findings before obtaining biopsy.

Carcinoma, Squamous Cell↗
PubMed2002

Standard ENT clinical evaluation of the sleep-disordered breathing patient; a consensus report.

Sleep disordered breathing (SDB) patients usually undergo an ENT clinical examination before any therapeutic decision. This clinical examination would be predictive about the occurrence of Obstructive Sleep Apnea Syndrome, cost effective, reproducible and would determine the sites of obstruction in the upper airways. To achieve this, ENT specialists from Belgium, representatives of academic hospitals in the country, have tried to establish an updated work-up in the clinical evaluation of the SDB patients. History, risk factors evaluation, excessive daytime sleepiness, static and dynamic evaluation of the upper airways (velopharynx aspect, tonsils grading, Mallampati score, Müller's maneuver, fiberoptic evaluation) have been standardized in a consensus report easily accessible to the vast majority of ENT specialists. This consensus must be understood as a clinical work-up to perform before the monitoring of breathing during sleep.

Belgium↗
PubMed2002

UPPP for snoring: long-term results and patient satisfaction.

We retrospectively survey 57 patients who underwent uvulopalatopharyngoplasty (UPPP) because of habitual snoring over a five-year period. A total of 100 patients were sent questionnaires concerning persistent snoring, excessive daytime sleepiness (EDS), body mass index (BMI) and postoperative complications. After 5 years the success rate was 53%. The mean snoring score was 16.7 preoperatively and decreased to 10.6 postoperatively. There was a relationship between the body mass index (BMI) preoperatively and the efficiency of the surgery. The mean EDS score was 11.1 before and 9.4 after surgery. UPPP in patients complaining of snoring is quite successful but the results decline significantly with time and patients should be warned of the possibility of snoring remaining or returning.

Body Mass Index↗
PubMed2002

Surgical treatment of the sleep-disordered breathing patient; a consensus report.

Sleep disordered breathing patients may undergo surgical treatment after history, clinical examination and polysomnographic study if they demonstrate upper airway obstruction. This article focus on the surgical treatment designed for these patients. Sino-nasal surgery, rhinopharyngeal procedure, velopharyngeal procedures (Uvulopalato-pharyngoplasty, Laser assisted uvulopalatoplasty, Radiofrequency tissue volume reduction) as well as base of the tongue procedures were discussed among a panel of Belgian ENT specialists offering their experience in this field. Algorithm on corrective surgery as well as guidelines for postoperative management are proposed in the management of sleep disordered breathing patients.

Belgium↗
PubMed2001

The levels of retinoid RARbeta receptors correlate with galectin-1, -3 and -8 expression in human cholesteatomas.

Cholesteatoma is a benign disease characterized by the presence of an unrestrained growth and the accumulation of keratin debris in the middle ear cavity. This often recurs, even when surgical resection is thought to be complete. In a previous study we showed that cholesteatomas with the highest apoptotic indices recurred more rapidly and also exhibited a high level of p53 immunopositive cells. In view of their relevance to the characterization of the cell differentiation status, the present study focuses on the expression of retinoid acid receptors (RARs) and galectins in human cholesteatomas. Retinoids control the differentiation processes in keratinocytes while galectins play strikingly modulatory roles at apoptosis and cell adhesion levels in a wide variety of tissue (embryonic, normal and neoplastic). To clarify the expression of these two protein families in human cholesteatomas we examined and quantified the levels of immunohistochemical expression of RARalpha, beta and gamma, and also galectin-1, -3 and -8 in a series of 70 human cholesteatomas. Our data show clearly that predominantly RARbeta and galectin-1 were expressed. The RARgamma concentration was significantly lower than that of the RARalpha; this was also observed for the galectin-8 concentration in comparison with the galectin-3 one. Furthermore, the level of RARbeta expression correlated highly (P=0.00001) with the level of galectin-8 expression, which also correlated significantly with the level of RARalpha and RARgamma expression. In addition, this parameter also correlated with the level of galectin-1 and galectin-3 expression. These data suggest that cholesteatomas may originate in an undifferentiated population of keratinocytes, and that a relation may exist between retinoid activity and galectins.

Adult↗
PubMed2001

The levels of expression of galectin-3, but not of galectin-1 and galectin-8, correlate with apoptosis in human cholesteatomas.

OBJECTIVES: To investigate whether galectins 1, 3, and 8 are expressed in human cholesteatomas and whether any such expression does correlate with the level of apoptosis, which is, as we have previously shown, predictive of recurrence.7 STUDY DESIGN: The analysis of 52 cholesteatomas resected by the same surgeon by means of canal wall up and canal wall down procedures. METHODS: The immunohistochemical levels of expression of galectins 1, 3, and 8 were quantitatively determined (using computer-assisted microscopy) on conventional histological slides by means of specific anti-galectin-1, anti-galectin-3, and anti-galectin-8 antibodies. The level of apoptosis in each cholesteatoma under study had already been determined 7 by means of the in situ labeling of nuclear DNA fragmentation (Tolt-mediated dUTP nick end labeling [TUNEL] staining). RESULTS: Galectin-1 was expressed markedly in both the epithelial and the connective tissue areas of all the cholesteatomas under study. The levels of expression of galectin-3 and galectin-8 were considerably lower than that of galectin-1. The level of expression of galectin-3 correlated both highly and positively with the level of apoptosis. CONCLUSIONS: An upregulation of galectin-3 (known to have an antiapoptotic and antianoikis effect in certain model systems) expression, which is associated with pronounced apoptotic activity, could have a physiologically protective effect against the characteristically substantial apoptotic features occurring in recurrent cholesteatomas.

Antigens, Differentiation↗
PubMed2001

Detection of macrophage migration inhibitory factor (MIF) in human cholesteatomas and functional implications of correlations to recurrence status and to expression of matrix metalloproteinases-3/9, retinoic acid receptor-beta, and anti-apoptotic galectin-3.

OBJECTIVES: To investigate whether the expression of the macrophage migration inhibitory factor (MIF) 1) is detectable, 2) changes in relation to recurrence and infection status, and 3) relates to the levels of expression of growth regulators/differentiation markers, including galectin-1, -3, and -8, retinoid acid receptors (RAR)]-alpha, -beta, and -gamma, binding sites for sarcolectin, and invasion markers (cathepsins -B and -D, and matrix metalloproteinases [MMP]-2, -3, and -9) in human cholesteatomas. STUDY DESIGN: An analysis of 56 cholesteatomas resected by the same surgeon using canal wall up and canal wall down surgical procedures. METHODS: The immunohistochemical levels of expression of MIF and the proteases were quantitatively determined (using computer-assisted microscopy) on routine histologic slides by specific antibodies, and statistically correlated to parameters of the other markers determined previously in conjunction with data on apoptosis/proliferation. RESULTS: MIF expression was detected. It was significantly higher in the epithelium (P =.002) and vessels (P =.04) of the connective tissues (but not in the connective tissue itself) of recurrent as opposed to non-recurrent cholesteatomas. The MIF expression is significantly correlated (P =.006) to the RAR beta expression in non-infected cholesteatomas, and to MMP-3 (P <.01) and anti-apoptotic galectin-3 (P =.01) in infected cholesteatomas. The level of MIF expression was also correlated significantly to MMP-9 (P = 0.003), RAR beta (P <.001), and galectin-8 (P =.003) expression in the cholesteatomas regardless of their infection status. CONCLUSIONS: MIF expression in human cholesteatomas is related to the levels of biologic aggressiveness reflected in their recurrence status and MMP expression, and to the differentiation status reflected in their galactin and RAR beta expressions. Together with galectin-3, it could cooperate to form an anti-apoptotic feedback loop.

Adolescent↗
PubMed2001

[Acute upper respiratory tract infections].

Acute infections of the upper respiratory tract are reviewed from an ENT point of view. Only the most frequent pathologies are taken into account. Clinical presentation and an update of current treatment are presented.

Adult↗
PubMed2000

Glycohistochemical characteristics of nasal polyps from patients with and without cystic fibrosis.

OBJECTIVE: To investigate whether cystic fibrosis (CF)-related nasal polyps exhibit significantly distinct glycohistochemical characteristics when compared with single vs massive nasal polyps obtained from patients without CF. DESIGN: Glycohistochemical characteristics were identified by means of 8 histochemical probes, including 5 plant lectins (peanut, gorse seed, wheat germ, Maackia amurensis, and Sambucus nigra agglutinins), 2 animal lectins (14- and 16-kd galectins), and 1 neoglycoprotein (exposing the Thomsen-Friedenreich antigen). The binding of the 8 glycohistochemical markers was determined by means of computer-assisted microscopy. For each probe, 3 quantitative parameters were computed: the labeling index, which describes the percentage of tissue area specifically stained by a given marker; the mean optical density, which reflects the staining intensity; and the concentrational heterogeneity, which characterizes the level of heterogeneity of the staining intensity. SUBJECTS: A series of 61 nasal mucosa specimens was analyzed, including 6 normal cases, 23 single and 18 massive polyposis cases without CF, and 14 nasal polyps associated with CF. RESULTS: Normal and polyposal nasal mucosa differed in terms of the amounts and linkage types of sialic acids (revealed by the wheat germ, M amurensis, and S nigra agglutinins) rather than the characteristics of galactoside expression (monitored with the peanut agglutinin and 2 animal galectins). In contrast, nasal polyps markedly differed between patients with and without CF with respect to galactoside expression (revealed by the peanut agglutinin and the 14-kd galectin) and the display of binding site(s) for the neoglycoprotein. CONCLUSION: Normal and polyposal nasal mucosa differ essentially in sialic acid presentation, while nasal polyps from patients with CF have a higher level of various lectin-reactive galactoside residues than nasal polyps from those without CF.

Cystic Fibrosis↗
PubMed2000

Synergistic combinatorial stroke therapy: A quantal bioassay of a GABA agonist and a glutamate antagonist.

We sought to prolong the window for stroke treatment using synergistic combinatorial therapy. We used the intraluminal filament occlusion model in rats to cause focal cerebral ischemia and a quantal bioassay to measure efficacy. The GABA agonist muscimol and the glutamate antagonist MK-801 were used alone and in combination at various times after ischemia onset. At progressively longer treatment delay intervals (30, 60, 75, 120, 240, and 360 min), higher doses of the single drugs were required to achieve neuroprotection. In contrast, the combination 1.0 mg/kg muscimol plus 0.5 mg/kg MK-801 was effective at all delay intervals studied except the longest (P < 0.05 at each time). After 240 min from ischemia onset, the combination was more effective than either single agent (P < 0.05 for each drug dose), suggesting synergism. The neuroprotective effect could not be demonstrated using morphometry. The treatment effects were probably not due to hypothermia because brain temperatures recorded in awake, unregulated subjects remained normo- or slightly hyperthermic following all treatments. Awake subjects kept on a heating pad exhibited mild brain hyperthermia. The combination caused a drop and MK-801 caused a significant increase in mean arterial blood pressure (main effects F(5,172) = 29, P < 0.0001). The combination of a GABA agonist and glutamate antagonist appears to possess synergistic neuroprotective effects when treatment is delayed up to 240 min following the onset of cerebral ischemia. Temperature regulation causes hyperthermia in awake subjects. The quantal bioassay is one method suitable for studies of synergistic stroke therapy.

Animals↗
PubMed2000

Correlation of galectin-3/galectin-3-binding sites with low differentiation status in head and neck squamous cell carcinomas.

The accurate determination of levels of differentiation is of prognostic value in human head and neck squamous cell carcinomas (HNSCCs). Because the deliberate selection of biochemical determinants accompanying certain stages of differentiation can refine the predictive power of histochemical assessments, the application of the quantitative evaluation of staining distribution and intensity by computer-assisted microscopy is one prerequisite to potential improvements. We used 2 innovative approaches with peanut agglutinin based on encouraging results with respect to common lectin-histochemistry. First, we used a custom-made neoglycoprotein to monitor the presence of Thomsen-Friedenreich (T) antigen-binding sites. Second, we measured the presence of 2 galectins immunohistochemically and, at the same time, measured lectin-histochemically the presence of accessible ligands for the endogenous lectins. We also monitored the presence of calcyclin, a protein with relevance to cell cycle progression or exocytosis. With 61 cases of HNSCC as their basis, including 31 oral, 20 laryngeal, and 10 hypopharyngeal lesions, the data show that the main modifications observed in connection with a loss of differentiation are related to a modification in the levels of both galectin-3/galectin-3-binding site and T-antigen/T-antigen-binding site expressions. The data obtained also suggest that galectin-3 could act as an acceptor site for the T antigen. Because the level of differentiation is known to be indicative of the recurrence rate in HNSCCs and our data clearly indicate that galectin-3 and the T antigen (and their respective binding sites) are involved in dedifferentiation processes, further investigation is warranted into the roles of galectins in HNSCC tumor progression and recurrence analysis.

Aged↗
PubMed2000

Effect of ganaxolone in a rodent model of cerebral hematoma.

BACKGROUND AND PURPOSE: Therapy with gamma-aminobutyric acid (GABA) agonists appears to improve outcome after experimental hematoma but with unacceptable side effects. We looked to synthetic GABA agonists, or positive GABA modulators, widely developed as anticonvulsants and anxiolytics, to find compounds that may be effective. Ganaxolone is a synthetic neuroactive steroid that positively modulates GABA. We sought to determine whether ganaxolone was beneficial using a model of intracerebral hematoma. METHODS: We stereotaxically injected varying doses of bacterial collagenase into the caudate nucleus of rats to induce blood-brain barrier failure and hematoma formation. Four hours later, we administered intravenously 15 or 30 mg/kg ganaxolone (n=23 each group), 20 mg/kg pregnanolone (n=21), or vehicle (n=30). Forty-eight hours after collagenase injection, we rated each animal using a standard rodent neurological examination. The ratings were compared with the amounts of injected collagenase using the quantal bioassay procedure. Other sets of animals were tested later for visuospatial learning. Brains were then prepared for histomorphometry, and brain volumes were estimated. RESULTS: We found that ganaxolone 30 mg/kg significantly increased the ED(50) in the bioassay, for a potency ratio of 1.8+/-0.41 compared with vehicle (P<0.05). Ganaxolone 15 mg/kg and pregnanolone did not affect neurological outcome. Ganaxolone 30 mg/kg did not clearly improve visuospatial learning several weeks after hemorrhage. Ganaxolone exhibited a weak effect on cerebral volumes 48 hours after stroke, but 3 months after hemorrhage no such effect could be detected. CONCLUSIONS: Ganaxolone improves neurological outcome 48 hours after intracerebral hematoma but not visuospatial learning several weeks after intracerebral hematoma. Histological evidence of damage was reduced at 48 hours but not at 3 months.

Animals↗
PubMed2000

Intranasal endoscopic surgery in traumatic optic neuropathy--the Belgian experience.

The management of traumatic optic neuropathy remains controversial. In this report we present the results of 8 patients treated by means of an intranasal endoscopic approach to the optic canal after at least 12 hours of corticosteroid therapy without improvement. Vision improved in four of the eight patients who underwent the surgery. There was no morbidity or mortality. As the results of the endoscopic optic nerve decompression are comparable to those reported using other surgical procedures, we feel that this approach merits consideration by surgeons.

Adult↗
PubMed2000

Mucins and secreted factors.

Mucin is a large glycoprotein (M up to 4-6.10(6)) with a high content of serine, threonine, and proline residues and numerous O-linked saccharides, often occurring in clusters on the polypeptide. Nine mucin genes exist in humans that encode an apomucin highly modified by O-glycans in forming epithelial mucins. These are variably expressed by epithelial cells of the gastrointestinal, tracheobronchial and reproductive tracts. They may be found either membrane-associated or secreted. As might be imagined from their ubiquitous and complex nature, the biological roles of glycans are quite varied. Protection against infection is an important biological role. Alterations in their carbohydrate moiety have been reported in airway and salivary mucins secreted by patients suffering of cystic fibrosis (CF). Moreover, changes in expression of glycans are also often reported in the setting of transformation and progression to malignancy. Due to the key roles played by glycans of glycoconjugates in both physiological and pathological events, glycobiology and carbohydrate chemistry have become of increasing importance in modern biotechnology.

Carcinoma↗
PubMed1999

The levels of expression of galectin-1, galectin-3, and the Thomsen-Friedenreich antigen and their binding sites decrease as clinical aggressiveness increases in head and neck cancers.

BACKGROUND: The aim of this study was to investigate whether an increase in malignancy level is accompanied by significant modifications of the expression of galectin-1, galectin-3, and Thomsen-Friedenreich antigen (T antigen) as well as the expression of binding sites for these three markers in head and neck squamous cell carcinomas (HNSCCs). METHODS: Immunohistochemical and glycohistochemical staining reactions were carried out with antibodies, labeled lectins, and a custom-made neoglycoprotein on the basis of histologic slides from a retrospective series of 40 normal and 75 HNSCC formalin fixed, paraffin embedded tissues, and were quantitatively described with the aid of computer-assisted microscopy. RESULTS: Whatever the histologic type, the epithelial tissues in HNSCC exhibited very significantly (P < 0.01 to P < 0. 0001) lower amounts of galectin-1, galectin-3, and T antigen and their respective binding sites than their corresponding normal counterparts. The tumors of the larynx differed very significantly (P < 0.0001 to P < 0.000001) from all the other tumor types. A loss of differentiation in the HNSCCs is accompanied first by the loss of expression of galectin-3 and galectin-3-reactive sites and then by that of the T antigen and its binding site(s). The opposite feature was observed when the parameters associated with the TNM classification were taken into account. The negative lymph node HNSCCs could be distinguished (P = 0.02) from the positive lymph node HNSCCs on the basis of a loss of galectin-3 expression. The modifications occurring in the extent of expression of galectin-1 and galectin-1-reactive sites were relatively marginal in comparison with those observed for galectin-3-dependent and T- antigen-dependent staining. CONCLUSIONS: The decrease in the extent of expression of galectin-3 and galectin-3-reactive sites, T antigen and T antigen-binding sites, and, to a lesser extent, galectin-1 and galectin-1-reactive sites correlates significantly with an increasing level of clinically detectable HNSCC aggressiveness.

Adjuvants, Immunologic↗
PubMed1999

[How do physicians evaluate their medical school training. Retrospective survey of 4 groups of medical students 8-11 years after graduation].

A survey was conducted among 250 graduates of the Bobigny School of Medicine (University Paris-Nord) who had completed medical school from 1986 to 1989 in order to ascertain their opinion concerning the training received. Ninety former students (36%) responded. The mean age of the sample was 34 years; 46 women and 44 men. Most (88.9%) were practicing medicine, principally as general practitioners (61.8%). 81.6% felt they had been well prepared to practice medicine. The rate of satisfaction was higher in the area of fundamental science than in clinical science. The responders generally felt that teaching and validation methods should emphasize real situations. The main criticism concerning the curriculum was an insufficient degree of professionalism, particularly in fields currently of particular importance: epide miology, health economics, education, prevention, office management. Training was also considered to be insufficient in medical techniques, communication, priority decision making, team work, emergency care, organization of time and handling stress. The responders suggested that the future curriculum should focus more on information search, research methodology and computer science. The results of this survey collaborate findings of recent retrospective long-term analyses conducted in other European countries.

Education, Medical, Continuing↗
PubMed1999

Prenatal exposure to cigarette smoking is associated with a decrease in arousal in infants.

OBJECTIVE: Sudden infant death syndrome has been related to both exposure to prenatal cigarette smoke and impaired arousability from sleep. We evaluated whether healthy infants born to mothers who smoked during pregnancy had higher auditory arousal thresholds than those born to mothers who did not smoke and whether the effects of smoking occurred before birth. STUDY DESIGN: Twenty-six newborns were studied with polygraphic recordings for 1 night: 13 were born to mothers who did not smoke, and 13 were born to mothers who smoked (>9 cigarettes per day). Other infants with a median postnatal age of 12 weeks were also studied, 21 born to nonsmoking mothers and 21 born to smoking mothers. White noise of increasing intensity was administered during rapid eye movement sleep to evaluate arousal and awakening thresholds. RESULTS: More intense auditory stimuli were needed to induce arousals in newborns (P =.002) and infants (P =. 044) of smokers than in infants of nonsmokers. Behavioral awakening occurred significantly less frequently in the newborns of smokers (P =.002) than of nonsmokers. CONCLUSIONS: Newborns and infants born to smoking mothers had higher arousal thresholds to auditory challenges than those born to nonsmoking mothers. The impact of exposure to cigarette smoke occurred before birth.

Arousal↗