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S Segal

Publications and source records attributed to S Segal.

At least 739 records · Page 41Linked to original sources
PubMedDate not supplied

Brain metastases in epithelial ovarian carcinoma; two case reports.

The cases of two patients with epithelial ovarian carcinoma who had been treated with surgery and cisplatin-containing combination chemotherapy and had developed brain metastases are described. Modern protocols for management of advanced-stage epithelial ovarian carcinoma have resulted in prolonging the lives of the patients sufficiently for central nervous system metastases to become apparent and possible resistence of the 'blood brain' barrier to the currently used chemotherapeutic agents may have left the CNS 'unprotected' from metastases.

Brain Neoplasms↗
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Abrogation of metastatic properties of tumour cells by de novo expression of H-2K antigens following H-2 gene transfection.

H-2 gene transfection was used to restore expression of H-2K antigens in metastatic and non-metastatic subclones of a murine fibrosarcoma that lack their major histocompatibility complex-encoded H-2K antigens. De novo expression of H-2K reduced tumorigenicity and abolished the formation of metastasis in syngeneic mice. Expression of H-2K may lead to effective recognition of the disseminating tumour cells by the host immune system.

Animals↗
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Expression of a transfected human c-myc oncogene inhibits differentiation of a mouse erythroleukaemia cell line.

The Friend-virus-derived mouse erythroleukaemia (MEL) cell lines represent transformed early erythroid precursors that can be induced to differentiate into more mature erythroid cells by a variety of agents including dimethyl sulphoxide (DMSO). There is a latent period of 12 hours after inducer is added, when 80-90% of the cells become irreversibly committed to the differentiation programme, undergoing several rounds of cell division before permanently ceasing to replicate. After DMSO induction, a biphasic decline in steady-state levels of c-myc and c-myb messenger RNAs occurs. Following the initial decrease in c-myc mRNA expression, the subsequent increase occurs in, and is restricted to, the G1 phase of the cell cycle. We sought to determine whether the down-regulation is a necessary step in chemically induced differentiation. Experiments reported here indicate that expression in MEL cells of a transfected human c-myc gene inhibits the terminal differentiation process.

Animals↗
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Aplastic anemia in Isreal: evaluation of the etiological role of chloramphenicol on a community-wide basis.

A nationwide study of aplastic anemia in Israel revealed a mean yearly incidence of 7.1/1,000,000 in males and 8.7/1,000,000 in females. Twenty-five per cent of the cases reported had an apparent chloramphenicol etiology. Ten patients, five treated with chloramphenicol and five without it, developed acute leukemia. The median survival was 11 months in males and 28 in females. Survival was particularly inferior in chloramphenicol-related cases, suggesting that this group constitutes a specific entity.

Acute Disease↗
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The art and science of teaching rounds. A strategy for staff development.

Teaching rounds can be a highly interactive, fluid process for developing staff nurses' critical thinking, assessment, and interpersonal skills. In this article, the authors describe how to conduct and evaluate teaching rounds using the example of Pain Management Teaching Rounds conducted by an advanced practice nurse on medical-surgical units of a large medical center. Qualitative and quantitative outcomes of the pain management rounds are discussed.

Adult↗
PubMedDate not supplied

The use of technetium in evaluation of the male accessory glands activity.

This study was performed with the purpose to elucidate the possibility of using Technetium 99m (Tc) as a marker for the evaluation of male sex glandular activity of the rat. Tc was injected into the femoral vein of the rat and its cpm was counted. The studies have shown that 22 hours after injection of Tc the material was accumulated in the glands in much higher values than its activity in the blood (which was only 1% of its zero time activity). In the rat, the dorsolateral coagulating gland has the highest capacity of accumulating Tc. Studies on castrated rats, or rats treated with testosterone enanthate, revealed that the activity of the cells in the glands and the volume of the excretion play an important role in the evaluation of the results. Thus, the use of Tc 99m in evaluating male accessory glands activity is a new interesting approach in the study of the physiology of the male sexual glands.

Animals↗
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Manipulation of metastasis and tumour growth by transfection with histocompatibility class I genes.

Approximately 50% of fibrosarcomas induced with methylcholanthrene A were found to be defective in H-2 expression. In tumours which lack H-2K antigens, H-2 gene transfection was used to restore H-2K expression. The de novo expression of H-2K reduced tumorigenicity and abolished the formation of metastases in syngeneic mice. Expression of H-2K seems to render the tumour cells immunogenic and leads to effective recognition of the tumour cells by the host immune system.

Animals↗
PubMedDate not supplied

NK sensitivity, H-2 expression and metastatic potential: analysis of H-2Dk gene transfected fibrosarcoma cells.

We have used the 3-Methylcholanthrene induced T-10 fibrosarcoma tumour cell system (H-2b xH-2k)F1 to elucidate the possible correlation between metastatic potential, expression of individual H-2 antigens and susceptibility to NK cells. Transfection of the non-metastatic and NK sensitive IC9 cells (Db+, Dk-, Kb-, Kk-) with the H-2Dk gene, altered the metastatic phenotype of the parental cells, yet had no effect on the susceptibility of these tumour cells to lysis by NK and did not elicit a specific CTL response in syngeneic hosts. Variants of the metastatic and NK resistant IE7 clone (Db+, Dk+, Kb-, Kk-), lacking H-2Dk, were selected by treatment with monoclonal anti H-2Dk antibodies and complement. These variants were sensitive to NK and poorly or non metastatic. Retransfection of 'Dk' 'loss' variants with the H-2Dk gene, resulted in the isolation of several clones expressing a wide range of metastatic phenotypes but maintained sensitivity to NK. These results indicate that the H-2D region of the MHC and or closely linked genes may be involved in the complex interrelationship between target susceptibility to NK and metastasis.

Animals↗
PubMedDate not supplied

Utilization of the nuchal translucency image-scoring method during training of new examiners.

Training of new examiners, utilizing 1st-trimester nuchal translucency ultrasound screening, is mandatory for obtaining reproducible measurements. This study examined the contribution of the nuchal translucency image-scoring method to the process of training and its utilization as an objective tool of image evaluation and a tool for approving qualification. The study included an evaluation of the performance of two new examiners (examiners A and B) before and after intervention, using the image-scoring method. The preintervention period included 75 images evaluated by two reviewers using general evaluation and the scoring method. The report of the scoring method was submitted to the examiners and was applied to 55 images performed afterwards. The agreement between two reviewers in classifying the first 75 images as 'accepted' or 'rejected' was tested using general evaluation versus the scoring method. The effect of the intervention was examined by comparing the quality of the images between the two time periods. A chart indicating final scores of 80 successive images analyzed by examiner A was used to set criteria for assessing qualification. Using general evaluation, the reviewers disagreed on 19 (25%) of the images, whereas using the scoring method they disagreed on only 5 (7%, p < 0.01). Comparison before and after application of the intervention demonstrated significant improvement expressed by the increased rate of better quality groups (p < 0.001) and improved mean scores from 4.31 +/- 0.31 to 6.15 +/- 0.32 (p < 0. 001). Enhanced improvement of examiner's A performance could be attributed to the intervention rather than to his learning curve. Improvement was demonstrated in all the criteria examined; however, it was significant only for images size (from 33 to 98%), amnion demonstration (from 13 to 42%), and caliper placement (from 49 to 71%). Examiner's A chart enabled us to set standards for assessing competence, based on the scoring method. These included a minimum of 40 scans, followed by more than ten sequential images of acceptable quality. The scoring method contributed to the process of training, as it made possible to objectively evaluate the images, pointed out specific errors, served as an efficient tool of intervention, and might be used for ascertaining competence. We recommend to consider its utilization in centers running 1st-trimester ultrasound screening during training new examiners.

Education, Medical, Continuing↗
PubMedDate not supplied

Chronic sinusitis: a sequela of inferior turbinectomy.

Inferior turbinectomy has generated a great deal of controversy among rhinologic surgeons. Proponents of partial and total inferior turbinectomy cite numerous studies of large numbers of patients with subjective relief of nasal obstruction after turbinectomy. Clinical studies critical of turbinectomy have focused on complications such as hemorrhage, crusting, adhesions, and atrophic rhinitis. Our study was undertaken to evaluate the incidence of chronic sinusitis post inferior turbinectomy. Postoperative evaluation by history, physical examination, and computerized tomography of the paranasal sinuses revealed that a significant number of patients who underwent inferior turbinectomy developed sinusitis. Patients evaluated in our clinic for nasal obstruction underwent a detailed history, physical examination along with nasal endoscopy and coronal computerized tomography of the paranasal sinuses. Those patients with nasal obstruction not responsive to medical treatment and without evidence of sinusitis underwent submucous resection and inferior turbinectomy. The incidence, cause, and possible prevention of post inferior turbinectomy sinusitis is discussed in this article.

Adolescent↗
PubMedDate not supplied

Impairment of cellular immunity in patients with malignant external otitis.

Immunological studies were performed on 4 elderly diabetic patients with Malignant External Otitis caused by Pseudomonas aeruginosa. Impairment of cellular immunity was found. Skin tests for delayed hypersensitivity to PPD, SK-SD and Mumps antigen were negative and stimulation rates of peripheral blood lymphocytes by PHA, Con-A and PWM were depressed in all 4 patients. Serum immunoglobulins and complement levels were normal except in one case in which paraprotein IgG was found. Peripheral blood lymphoid cell markers and the neutrophil nitroblue tetrazolium (NBT) test were within normal limits in the 2 patients tested. These results indicate that cellular immune deficiency predisposes to the development of Malignant External Otitis in elderly diabetic patients.

Aged↗
PubMedDate not supplied

Differential transcriptional control of the H-2K and H-2D loci of the major histocompatibility complex in fibrosarcoma cells.

In this study we demonstrate a differential transcription of H-2K and H-2D class-I genes in two different tumor cell clones; one is highly metastatic (IE-7) and the other is not metastatic (IC-9), both derived from the same fibrosarcoma, T-10, induced in an (H-2b x H-2k)F1 mouse. The expression of the two parental H-2K alleles is transcriptionally suppressed in both of these clones. In addition the IC-9 clone does not transcribe also the H-2Dk allele. Our data rule out the possibility that this suppression results from enhanced RNA degradation, impaired polyadenylation, DNA rearrangement, or changes in DNA methylation within these genes. Interferons (IFN) are known to enhance MHC expression by acting on a consensus IFN responsive element present in the promoter region of MHC genes. However, IFN-gamma, which is the most potent IFN in this respect, failed to activate the expression of the silent MHC genes in our cells. This finding may reflect a defect within the promoter region of these genes or changes in their chromatin structure.

Alleles↗
PubMedDate not supplied

Inner ear damage in children due to noise exposure from toy cap pistols and firecrackers: a retrospective review of 53 cases.

This retrospective study presents the findings of inner ear damage documented in 53 children exposed to impulsive sound emitted by toy weapons and firecrackers. There were 49 boys and four girls aged between four and fourteen years. Thirty-nine children were affected unilaterally while fourteen had bilateral hearing loss (total of 67 ears). Most of the hearing loss (>70%) was sensorineural high frequency hearing loss, while only nine out of the 67 injured ears had sensorineural mid frequency hearing loss. Seven children sustained a traumatic ear drum perforation. Dizziness or tinnitus was reported by twenty children, with pathological ENG findings in four of them. This paper re-emphasizes the possibility of inner ear damage in children from exposure to noisy toys.

Adolescent↗
PubMedDate not supplied

[Reflex otalgia].

Explore the source record for details and available documents.

Cervical Vertebrae↗
PubMedDate not supplied

Aberrations in interleukin-1 expression in oncogene-transformed fibrosarcoma lines: constitutive interleukin-1 alpha transcription and manifestation of biological activity.

We have examined interleukin-1 (IL-1) expression in a series of oncogene-transformed NIH-3T3 fibroblastoid cell lines. In contrast to primary fibroblasts where IL-1 is inducible, NIH-3T3 cells (clone 490N3T) transcribe the IL-1 alpha gene constitutively. Transformation of 490N3T cells by the v-mos or v-H-ras oncogenes appears to either enhance or suppress IL-1 alpha transcription, respectively. In v-myc transfected cells, constitutive IL-1 activity could be detected intracellularly. An additional membrane-associated form of IL-1 was observed in lines transformed by protein-kinase (PK) encoding oncogenes, such as TPR-met, c-met, v-src, v-abl, v-mos and v-raf. In none of the lines tested the secreted form of IL-1 activity could be detected, and no constitutive expression of IL-1 beta was observed. Our studies manifest aberrations in IL-1 expression in oncogene-transformed fibroblastoid cell lines, detected at different regulatory levels, such as transcription, translation and compartmentalization. IL-1 is a potent pleiotropic cytokine, with regard to its target cell specificity and spectrum of activities; growth promoting effects of IL-1 on fibroblasts were reported and on the other hand this cytokine activates various anti-tumor mechanisms. Thus, endogenous IL-1 expression by tumor cells may affect the neoplastic phenotype, either by influencing the growth of the malignant cells or by modifying tumor-host interactions.

3T3 Cells↗
PubMedDate not supplied

Potential use of tuftsin in treatment of candida peritonitis in a murine model.

A major complication of continuous ambulatory peritoneal dialysis (CAPD) is peritonitis caused by Candida albicans. Increasing the activity of the peritoneal macrophages, the predominant cell type found in the peritoneal cavity, may be a promising treatment for this infection. Tuftsin was found to increase thioglycollate-elicited mouse peritoneal macrophage activity. 2x10(-7) M tuftsin enhanced two-fold cell association with radiolabelled candida, superoxide aniom production, and killing activity. Thus, a model consisting of mice undergoing peritoneal dialysis was developed in order to study the use of tuftsin as a therapeutic drug against peritoneal candidiasis. Administration of tuftsin (50 micrograms/mouse) before candidiasis induction with a lethal dose of candida (7x10(8) candida per mouse) improved mouse survival up to 70%, compared with 10% in the control group. The potential of tuftsin as a treatment for candidiasis was shown when the infection was induced with a sublethal dose of candida. Daily intraperitoneal injections of tuftsin (50 micrograms) to the sublethally infected mice caused a significant decrease in the number of candida recovered from the peritoneal cavity and from the blood (from 700 +/- 190 to 110 +/- 26 CFU/ml and from 100 +/- 26 CFU/ml to 17 +/- 8 CFU/ml, respectively). In addition, a larger number of peritoneal macrophages with greater phagocytic and killing activity were found in the tuftsin-treated mice. The effect of tuftsin may promote its potential use in the therapy of peritonitis in patients undergoing chronic peritoneal dialysis.

Animals↗