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Y Zohar

Publications and source records attributed to Y Zohar.

At least 55 records · Page 3Linked to original sources
PubMed1995

Internal jugular vein patency after functional neck dissection: venous duplex imaging.

We present a retrospective study performed to determine jugular patency after functional neck dissection (FND). Twenty-six patients, 16 females and 10 males, ranging in age from 16 to 78 were examined. These patients underwent either unilateral FND or bilateral FND for cervical lymph node metastases. Cervical duplex and pulsed Doppler imaging were chosen to determine internal jugular vein (IJV) patency. The examination was performed after a minimum postoperative period of 2 months and a maximum one of 22 years. Thirty-one IJVs were examined. All but 4 IJVs examined were found patent postoperatively. The preservation rate of patency of the IJV in FND was found to be high (27 of 31 or 87%). These results favor the use of FND for IJV preservation, particularly in bilateral neck dissection.

Adolescent↗
PubMed1995

Auditory brainstem response in obstructive sleep apnea patients.

Auditory brainstem responses (ABR) were recorded in 79 patients diagnosed as suffering from obstructive sleep apnea (OSA). The patients were divided into three subgroups (mild, moderate and severe) according to the severity of the syndrome. A statistically significant prolongation was found in the latency values of waves I, III and V in all three subgroups, compared to a control group of 29 healthy subjects. The transmission time between waves I and III and I and V was found to be prolonged in the moderate and severe OSA subgroups, compared to the control group. However, from a clinical point of view only 10% (eight patients) of the OSA group showed a clinically significant prolongation in their ABR latency values compared to the norms (mean +/- 2SD) of the specific ABR recording system used in this study. In addition, 36 of the OSA group underwent uvulopalato-pharyngoplasty (UPPP). There were no statistically significant differences in the ABR recording preoperatively versus post-operatively.

Adult↗
PubMed1995

Molecular cloning and sequence analysis of striped bass (Morone saxatilis) gonadotrophin-I and -II subunits.

Two types of cDNA, each encoding a different beta-subunit of striped bass (Morone saxatilis, Teleostei) gonadotrophins (GTH-I beta and GTH-II beta), as well as the glycoprotein alpha-subunit, were cloned by screening a striped bass pituitary cDNA library. The probes used for screening the library were cloned cDNA fragments, generated by PCR amplification of reverse-transcribed mRNA obtained from two pituitaries. The nucleotide sequences of the alpha-subunit, GTH-I beta and GTH-II beta are 626, 524 and 580 bases long, encoding peptides of 117, 120 and 147 amino acids respectively. Striped bass GTH-I beta and GTH-II beta share a sequence identity of 48% at the nucleic acid level, and 30% at the amino acid level. A cluster analysis of vertebrate pituitary glycoprotein beta-subunits suggests that teleost GTH-II beta is more closely related to tetrapod LH than to FSH. Administration of gonadotrophin-releasing hormone analogue ([D-Ala6,Pro9Net]-LHRH) to juvenile striped resulted in ten-, two- and fivefold increases in the expression of the alpha-subunit, GTH-I beta and GTH-II beta respectively. These results suggest that each of the GTH subunits is differentially regulated, and further corroborate the functional duality of teleost gonadotrophins.

Amino Acid Sequence↗
PubMed1995

Molecular cloning and characterization of a novel gonadotropin-releasing hormone from the gilthead seabream (Sparus aurata).

A novel form of gonadotropin-releasing hormone (GnRH) had been recently isolated and characterized from the gilthead seabream (Sparus aurata). This novel form, designated sbGnRH, was suggested to be the endogenous stimulator of gonadotropin release. This paper reports on the isolation and characterization of a 360-bp cDNA encoding the complete sbGnRH precursor. This precursor is composed of a 25 amino acid leader sequence, the biologically active sbGnRH, the cleavage site (Gly-Lys-Arg), and a 57 amino acid associated peptide (GAP). Comparison of the nucleotide and amino acid sequence of the sbGnRH precursor with precursors of other GnRH forms places the sbGnRH precursor evolutionarily closer to the mammalian GnRH and chicken GnRH-I, which have also been shown to be the relevant forms for gonadotropin release in mammals and birds, respectively. The characterization of the sbGnRH precursor cDNA lays the foundation for future studies aimed toward understanding the neuroendocrine control of reproduction in seabream and other fish species.

Amino Acid Sequence↗
PubMed1994

Three forms of gonadotropin-releasing hormone characterized from brains of one species.

Most vertebrate species have more than one form of gonadotropin-releasing hormone (GnRH) in their brains, but it is not clear whether each form has a distinct function. We report that sea bream (Sparus aurata) brains have three forms of GnRH, one of which is described herein and is called sea bream GnRH (sbGnRH). The primary structures of two forms were determined by Edman degradation and mass spectral analysis. The amino acid sequence of sbGnRH is pGlu-His-Trp-Ser-Tyr-Gly-Leu-Ser-Pro-Gly-NH2. The second peptide is identical to a form originally isolated from chicken brains (cGnRH-II): pGlu-His-Trp-Ser-His-Gly-Trp-Tyr-Pro-Gly-NH2. cGnRH-II is the most ancient form of GnRH identified to date in jawed fish and the most prevalent form throughout the vertebrates. The third form of GnRH has previously been identified as salmon GnRH by cDNA studies and is confirmed here by chromatographic and immunological studies. Phylogenetic distribution of GnRH peptides suggests sbGnRH arose in the perch-like fish as a gene duplication of the existing cGnRH-II or salmon GnRH genes. All three identified GnRH peptides were synthesized and shown to release gonadotropin in vivo in the sea bream. The dominant form of GnRH stored in the pituitary was sbGnRH. Not only was the content of sbGnRH 500-fold greater than that of salmon GnRH but also cGnRH-II was not detected in the pituitary. The latter evidence suggests that sbGnRH is the endogenous releaser of gonadotropin II.

Amino Acid Sequence↗
PubMed1994

[Human fibrin glue in head and neck surgery].

Promoting tissue adhesion is of concern in almost all areas of surgery. Human fibrin, thrombin and clotting factor XIII have important roles in the healing of wounds and in scar formation. The gluing material we use is a prefabricated fibrinogen concentrate produced from pooled human blood plasma (Tisseel Kit, Immuno), obtained from plasmapheresis centers in Central Europe and the US. The gluing solution averages 110 mg/ml of coagulable material. On applying a thrombin solution (by dripping it onto the area), fibrinogen coagulated in 8-10 seconds (quick coagulation) or 30-50 seconds (slow coagulation). Fibrin glue is valuable in tissue synthesis and tissue adhesion, particularly where conventional suture methods would be difficult. We summarize results in 53 patients operated on between 1985-1993. The Tisseel tissue adhesive system was used for coating and sealing during tympanoplasty (18 patients), and for closure of perilymphatic fistulas (18), chylous fistulas (2), oral and pharyngeal fistulas (3), cerebrospinal fluid leaks (4), facial nerve injury (1), and in split-thickness skin graft and local skin flap application in hereditary hemorrhagic telangiectasia (7). Tissue glue is valuable in tissue repair and local hemostasis, facilitates the surgeon's work and may obviate more complicated surgical procedures.

Fibrin Tissue Adhesive↗
PubMed1994

[Thyroidal oxyphilic tumors].

Treatment of thyroidal oxyphilic (Hurthle cell) tumors is controversial due to difficulties in grading tumor malignancy. We classify these tumors into 3 histological subtypes: adenomas, atypical adenomas, and carcinomas. The purpose of this study was to find out whether this classification is a useful criterion for determination of the extent of surgery. Our retrospective study included 5 cases of adenoma, 2 of atypical adenoma and 13 of carcinoma. All histological specimens were revised and were stained immunohistochemically for thyroglobulin. All specimens were positive for thyroglobulin; staining for factor VIII was performed in cases in which the tumor had penetrated into blood vessels. Hemithyroidectomy was used for typical adenomas, while atypical adenomas were treated as carcinomas and total thyroidectomy was performed. 5 patients were treated with radioactive iodine. Taking into account the clinical results, we conclude that histological subtype is a useful guide for proper surgical management. Hemithyroidectomy is proper therapy for adenomas. The management of atypical adenomas was not determined as all were treated as carcinomas.

Adenoma↗
PubMed1994

Adult-onset otitis media with effusion.

OBJECTIVE: To document the prevalence of adult-onset otitis media with effusion (OME), and to determine its causes, diagnostic approach, and therapeutic management. DESIGN: A prospective study of 167 consecutive patients with adult-onset OME. Endoscopic examination of intranasal and nasopharyngeal structures with special attention to the eustachian tube orifices was performed in all patients. In 65 patients computed tomography of the skull base, neck, and paranasal sinuses was also performed. RESULTS: Paranasal sinus disease, predominantly of the ethmoid system, was found to be the dominant causal factor in 110 patients (66%). Smoking-induced nasopharyngeal lymphoid hyperplasia and adult-onset adenoidal hypertrophy, two entities herein described, were the cause of OME in 15 patients (19%). Various other causes were found in 31 patients. Head and neck tumors, mainly nasopharyngeal carcinomas, were found in only eight patients (4.8%). The cause of adult-onset OME could not be determined in three patients (1.8%). CONCLUSIONS: Contrary to common belief, adult-onset OME is not an uncommon disease. Nasendoscopy is the mainstay of diagnostic evaluation in most patients. Computed tomography is also an important tool in most selected cases. Appropriate treatment of sinusitis resulted in resolution of OME in most patients. Sinusitis is the most common causal factor of adult-onset OME, but nasopharyngeal and parapharyngeal space-occupying lesions should be ruled out in all cases.

Adolescent↗
PubMed1994

CT target selection in stereotactic anterior capsulotomy: anatomical considerations.

The first communications concerning stereotactic bilateral anterior capsulotomies were reported by Talairach and Leksell. This procedure has become established for the management of otherwise intractable anxiety neuroses and obsessive compulsive disorders, with a reported success rate of 70% in different series. It has been stressed that results are closely related to the extent of the lesion. The desirable lesion has a tubular shape with a length of 15-18 mm in the coronal axis. This shape is achieved by step withdrawal of a 4- to 5-mm electrode tip along a proper trajectory. A precise angulation of the trajectory is crucial to proceed without lesioning of the adjacent bordering caudate nucleus or putamen in the coronal plane. In the sagittal plane, it has to remain within the limits of the anterior capsula interna and avoid an excessive posteroanterior obliquity to ensure that the entry point through the cortex remains in the prefrontal noneloquent area. To achieve this trajectory, a target 5 mm posterior to the anterior border of the frontal horn, as seen on CT, at the level of the foramen of Monro has been suggested, along with a precoronal burr hole placed 20 degrees from the midline. Following these guidelines we have found the resulting lesions to be excessively anterior, with exclusion of their first 4- to 5-mm deep component. If the same target point is selected at two different axial levels to fix a trajectory, it usually results in an anteriorward trajectory that might require an entry point too close to the motor cortex, because the anterior horn reaches more rostrally as it deepens.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain Mapping↗
PubMed1994

[Endemic goiter in a non-goitrogenic country].

Although goiter is not endemic in Israel, an iodine-rich country due to its bordering on the Mediterranean, we see many adults with massive goiters among immigrants from Afro-Asian and eastern European countries. 702 thyroidectomies were performed between January 1986 and March 1993 and 39 consecutive cases of goiter were studied. The patients ranged in age from 32-83 years (mean, 48); the female/male ratio was 36/3. There were 15 cases (13%) of thyroid carcinoma. In 1 case hyperthyroidism was diagnosed and treated preoperatively (3%) and in 2 others subclinical hypothyroidism was found (5%). The cervical approach was used, including cases with substernal extension. In only 1 was sternal splitting necessary. In our experience enlarged nodular goiter, with or without substernal extension, should be operated before symptoms of tracheal pressure develop and to avoid the risk of neglected malignancy hidden in an enlarged thyroid.

Adult↗
PubMed1993

The otolaryngologist and the patient with velocardiofacial syndrome.

Velocardiofacial syndrome is the most common syndrome associated with clefting of the secondary palate. The endoscopically diagnosed occult submucous cleft palate is the most common palate anomaly associated with this syndrome. Patients with velocardiofacial syndrome present a special challenge to the otolaryngologist, who must be familiar with the diagnostic and therapeutic aspects of this syndrome. We report the findings in 21 patients with velocardiofacial syndrome. Only 11 (52%) had the typical manifestations, and others had only partial phenotype. Adenoidectomy must be avoided in these patients, since undiagnosed occult and overt submucous cleft palate are the most common cause of velopharyngeal insufficiency after adenoidectomy. Three patients had aberrant carotid arteries. This anomaly must be excluded by nasoscopy and computed tomographic scanning before pharyngeal flap surgery is considered in these patients. Criteria for exclusion of high-risk patients from adenoidectomy are presented and discussed.

Abnormalities, Multiple↗
PubMed1993

Surgical treatment of obstructive sleep apnea. Technical variations.

OBJECTIVE: To determine the effectiveness of the two basic surgical types of uvulopalatopharyngoplasty (UPPP), as classified by us. The two basic surgical variations of UPPP differ for the width of the anteroposterior palatal resection, being 1 to 2 cm (type 1) and 0.5 to 1.0 cm (type 2). DESIGN: Randomized, retrospective study. PATIENTS: Eighty-seven patients with obstructive sleep apnea hospitalized in our department from 1983 to 1991. All patients had a complete preoperative and postoperative polysomnographic evaluation. RESULTS: The operation was found to be an effective treatment of obstructive sleep apnea in most patients. Snoring improvement was found in 95% (29/31) of patients with type 1 UPPP and in 96% (54/56) of the patients with type 2 UPPP, whereas, apnea index improvement was detected in 65% (20/31) of the patients with type 1 UPPP vs 64% (36/56) of the patients with type 2 UPPP. Postoperative dysphagia was found in 94% (29/31) vs 79% (44/56), P = .0025; nasal reflux was found in 81% (25/31) vs 11% (6/56), P = .0001; and hypernasality was found in 100% (31/31) vs 13% (7/56), P = .0001, in type 1 and type 2 UPPP operations, respectively. Chi-square analysis shows highly significant differences. CONCLUSIONS: Type 2 UPPP is the recommended surgical procedure of obstructive sleep apnea, mainly due to the minimal postoperative morbidity.

Deglutition Disorders↗
PubMed1993

Nasopharyngeal profile and velopharyngeal valve mechanism.

Proper management of velopharyngeal insufficiency requires an understanding of normal velopharyngeal anatomy and function. The present cephalometric study correlates the nasopharyngeal profile at rest with velopharyngeal function as observed by nasendoscopy and fluorographic and videofluoroscopic studies. Fifty-two normal individuals and 23 patients with insufficient velopharyngeal valves were examined. A correlation was found between nasopharyngeal profiles at rest and the closure patterns of the velopharyngeal valve. It was found that when existent, Passavant's ridge is subsequently formed where thick soft tissue corresponding to the superior constrictor muscle is found beneath the mucosa of the posterior pharyngeal wall at rest. Our conclusion is that Passavant's ridge is formed by the superior constrictor. The present study represents additional confirmation that differences in velopharyngeal closure patterns are the result of differences in anatomy. A biomechanical model of velopharyngeal valving is presented based on individual spatial muscular orientation and the hierarchical recruitment of the velopharyngeal muscles. This recruitment is progressive and is dependent on the effort required to achieve tighter velopharyngeal sealing.

Adult↗
PubMed1993

Endoscopic diagnosis and treatment of persistent halitosis after pharyngeal flap surgery.

A patient presenting with persistent dramatically offensive fetid malodor 1 year after pharyngeal flap surgery is described. Nasendoscopic examination revealed the presence of a foreign body within the nasopharynx lying on the flap. The foreign body was immediately removed by endoscopic telebiopter and revealed itself to be a gauze pad forgotten during the pharyngeal flap surgery. Modern endoscopic equipment allowed both quick diagnosis of this very rare complication and immediate and simple treatment under topical anesthesia.

Adult↗
PubMed1993

Recurrent laryngeal nerve paralysis during transvenous insertion of a permanent endocardial pacemaker.

We present 2 patients with sudden onset of dysphonia due to acute unilateral vocal cord paralysis that occurred during transvenous insertion of a permanent endocardial pacemaker. Acute paralysis of the vocal cord due to this kind of medical intervention is a very unusual complication that has been rarely reported. We believe that traumatic insertion of a pacemaker through the subclavian vein triggered a dynamic process that led to vocal cord paralysis. Three hypothetic explanations are presented: 1) a direct vagus nerve lesion, 2) a direct inferior laryngeal nerve lesion, and 3) a central nervous system lesion caused by a cerebral microembolus. Physicians should be aware of the possibility that associated acute paralysis of the vocal cord may occur after transvenous insertion of an endocardial pacemaker.

Acute Disease↗