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Biomedical subjects

J Spiegel

Publications and source records attributed to J Spiegel.

At least 37 records · Page 2Linked to original sources
PubMed1996

Laser-evoked potentials after painful hand and foot stimulation in humans: evidence for generation of the middle-latency component in the secondary somatosensory cortex.

The vertex potential (N2, P2) of the laser-evoked potential (LEP) is preceded by a small negativity (N1). The role of the secondary somatosensory cortex (SII) in generation of the N1 is established for the upper but not for the lower limb. We therefore investigated the N1 after painful radiant heat stimulation of hand and foot dorsum in 22 subjects. LEPs were recorded from the scalp with midline and temporal electrodes. After hand stimulation N1 was maximal in the contralateral temporal lead (mean peak latency 156 +/- 23 ms). After foot stimulation N1 was maximal in the same lead (200 +/- 22 ms). In the ipsilateral temporal lead, N1 appeared significantly smaller and later. N2 and P2 were maximal in midline electrodes for both stimulus sites. The latency shift between hand and foot stimulation was identical for all three components. These results suggest a contribution of temporo-parietal cortex (e.g. SII) to the N1 generation for stimulation of upper and lower limb.

Adult↗
PubMed1996

Peristomal hidradenitis suppurativa.

Hidradenitis suppurativa is a chronic, suppurative, and cicatricial cutaneous disease with clinical manifestations including inflammatory lesions and nodules, abscesses, and sinus tracts. We describe an unusual case of peristomal lesions that may represent hidradenitis suppurativa. Peristomal hidradenitis suppurativa has not been previously reported. This unusual complication demonstrates the need for a thorough patient history to identify any systemic disease that may contribute to peristomal skin problems.

Crohn Disease↗
PubMed1991

Delayed pharyngoesophageal perforation: a complication of anterior spine surgery.

Stabilization of the cervical spine is often accomplished via an anterior cervical approach. Bone grafts and/or plates and screws are used to achieve stabilization. Injuries to the pharynx and esophagus are known complications in anterior exposure of the cervical spine. These injuries are manifest in the early postoperative period. Reports of late perforations are very rare. We present four cases of delayed injury to the pharynx and esophagus that resulted in abscess or fistula. We postulate that graft displacement with resulting erosion was responsible for these serious complications. Postoperative odynophagia in patients who undergo anterior cervical fusion warrants evaluation of the bone graft location. Early surgical intervention and repair may decrease prolonged morbidity in these patients.

Abscess↗
PubMed1991

An analysis of occupational blood lead trends in Manitoba, 1979 through 1987.

BACKGROUND: While regulations for workplace lead exposure become more strict, their effectiveness in decreasing blood lead concentrations and the method by which this is attained have not been evaluated. METHODS: An analysis was conducted of 10,190 blood lead samples from employees of 10 high-risk workplaces collected in Manitoba, 1979-87, as part of regulated occupational surveillance. RESULTS: A significant decrease in blood lead concentrations was observed overall as well as for each individual company. A 1979 government regulation to reduce blood lead to below 3.38 mumol/L (70 micrograms/dl) was followed by a drop in blood lead concentrations; a 1983 order to reduce blood leads to below 2.90 mumol/L (60 micrograms/dl) was not followed by such a drop. Longitudinal analysis by individual workers suggested that companies were complying by use of administrative control, i.e., removing workers to lower lead areas until blood lead levels had fallen, then returning them to high lead areas. CONCLUSION: Focusing upon blood lead as the sole criterion for compliance is not effective; regulations must specifically require environmental monitoring and controls. Biological surveillance serves as "back-up" to environmental surveillance and this database illustrates the usefulness of a comprehensive centralized surveillance system.

Air Pollutants, Occupational↗
PubMed1990

Mechanization, the labor process, and injury risks in the Canadian meat packing industry.

During the 1980s, Canada's major manufacturing industries experienced considerable financial restructuring and technological transformation, largely in response to recessionary pressures. At the same time, the rate of lost-time injuries in Canadian manufacturing rose steadily. This article explores the relationship between these sets of factors. The meat packing industry has been selected as a case study of the interaction between industrial organization, the labor process, and the risk of workplace injuries. The authors suggest that the following factors have contributed to high and rising injury rates in the meat industry during the 1980s: consolidation into a smaller number of large, highly specialized, and mechanized plants; deteriorating labor relations in the face of falling profits; and an intensified labor process stressing line speedups and a growing risk of repetitive strain injuries. These observations are supported by a detailed analysis of the relationship between the labor process and workplace injuries at one packing plant considered typical for the industry.

Abattoirs↗
PubMed1988

Renal transplant obstruction by B cell lymphoproliferative disorder: case report and review of the literature.

We report a case of renal transplant ureteral obstruction caused by a cyclosporine-associated B cell lymphoproliferative disorder. The interaction of cyclosporine with Epstein-Barr virus infections and the predisposition towards B cell lymphoproliferative disorders are reviewed. The characterization of these tumors by deoxyribonucleic acid hybridization studies and a review of the clinical experience treating these disorders also are presented.

B-Lymphocytes↗
PubMed1986

Amino acid sequence of myosin essential light chain from the scallop Aquipecten irradians.

The amino acid sequence of the scallop myosin essential light chain (SELC) was determined from analysis of the intact, S-carboxymethylated protein and peptides produced by cleavage at its four methionine residues by cyanogen bromide digestion and at its six arginine residues by citraconylation and tryptic digestion. SELC contains 156 amino acid residues, including three cysteines, four tyrosines, one tryptophan, two histidines, and an unblocked amino-terminal proline. The protein has a calculated Mr of 17,616. SELC is an acidic protein, with a net charge of 18- at physiological pH. Comparative analysis reveals four homologous domains (I-IV), which arose by reduplication of a gene for a small, ancestral calcium binding protein. Each domain has a helix-loop-helix structure, with all the ligands for calcium binding located within a 12-residue segment that spans the loop and the first turn of the following helix. Potential calcium binding sequences were found in the ancestral sites III (residues 94-105) and IV (residues 132-143). Mutations in critical positions in domains I and II seem to preclude the possibility of calcium binding in the amino-terminal half of SELC. An unexpected third potential calcium binding segment (at residues 119-130, predicted to be in helical conformation) was found in domain IV. A reactive thiol group (Cys-78) that is involved in binding of regulatory light chains was tentatively located in an extended "linker region", which connects the two halves of the molecule.

Amino Acid Sequence↗
PubMed1986

Skin calcium-binding protein is a parvalbumin of the panniculus carnosus.

Skin calcium-binding protein (SCaBP) is a calcium binding protein purified from whole rat skin. It has a molecular weight of approximately 12,000 daltons but migrates at Mr 13,000 on sodium dodecyl sulfate (SDS)-polyacrylamide gels. On nitrocellulose blots of SDS-polyacrylamide gels, 6 different antisera to SCaBP reacted equally well with SCaBP and parvalbumin (PV), an 11,500-dalton calcium-binding protein purified from rat skeletal muscle, which also migrates at Mr 13,000 on SDS-polyacrylamide gels. Rabbit antiserum to muscle PV also recognized both PV and SCaBP, and either protein absorbed specific antibodies against either antigen from both types of antisera. Soluble protein extracts from whole adult rat and mouse skin contained a Mr 13,000 protein which was recognized on nitrocellulose blots of SDS gels by both antisera. Blots of extracts from epidermis, dermis, whole skin, and skin scraped on the dermal side to remove hypodermal tissue revealed that the Mr 13,000 PV/SCaBP cross-reacting antigen was restricted to the hypodermal tissue removed by scraping. Immunofluorescent staining of Bouin-fixed skin sections with these antisera confirmed the localization of PV/SCaBP to the panniculus carnosus, a hypodermal muscle layer. Newborn mouse skin does not contain this antigen. Additional polypeptides of Mr 10,500 and 12,000 on SDS gels of extracts from the epidermis of newborn and adult rats and mice were found to be immunoreactive with anti-SCaBP serum. These polypeptides were not recognized by the PV antiserum, and the reactivity of anti-SCaBP for these antigens was not absorbed by purified PV or SCaBP. Our results indicate that SCaBP is antigenically indistinguishable from PV and is localized in the adult rodent panniculus carnosus, and that antisera to SCaBP are polyspecific, recognizing epidermal proteins in addition to SCaBP/PV.

Animals↗
PubMed1985

AEC syndrome: ankyloblepharon, ectodermal defects, and cleft lip and palate. Report of two cases.

An unusual syndrome of ectodermal dysplasia was seen in a young woman and her son. The constellation of findings included hair, nail, and teeth dystrophies, as well as hypohidrosis. The patients appear to exhibit the previously described syndrome of ankyloblepharon, ectodermal defects, and clefting of the lip and palate. Their cases are the eighth and ninth cases reported in the literature.

Adult↗
PubMed1984

In vitro sensitivity and resistance of cultured human squamous carcinoma cells to cis-platinum and methotrexate.

To determine whether resistance to chemotherapy in advanced head and neck squamous cell carcinoma stems from biochemical mechanisms and to assess the potential usefulness of new anticarcinogens, an in vitro test would be highly desirable. In the past 4 years our laboratory has developed methodology to establish squamous carcinoma cell lines in tissue culture from patients with squamous cancer of the head and neck. We used some of these lines to compare the in vitro effects of methotrexate on squamous carcinoma, fibrosarcoma, and melanoma cells. Three of the squamous carcinoma lines were tested for sensitivity to both methotrexate and cis-platinum; all but one squamous carcinoma cell line exposed to methotrexate showed growth inhibition at the physiologically attainable concentration of 10(-7) M. In contrast, a tenfold higher concentration was required to produce similar effects in the melanoma, while no concentration inhibited fibrosarcoma growth. Cis-platinum showed consistent squamous carcinoma cytotoxicity in 10(-5) M and 10(-6) M concentrations. This approach should be useful for determining the relative sensitivity and resistance of head and neck cancers to chemotherapeutic agents in vitro.

Carcinoma, Squamous Cell↗
PubMed1983

Fibrous papule: an immunohistochemical study with an antibody to S-100 protein.

We studied twenty biopsies taken from fibrous papules which were located in the central part of the face. The lesions, which were characteristic histologically, did not contain S-100 protein within the stellate cells in the papillary dermis, nor was this substance found in mesenchymal cells with some features of nevus cells. In control studies, S-100 protein was found using an unlabeled antibody peroxidase-antiperoxidase technic within nevus cells composing junctional intradermal, and compound nevi, Spitz nevi, and halo nevi. It therefore seems unlikely that fibrous papule represents a form of degenerated nevus as some investigators have proposed.

Biopsy↗
PubMed1982

Malathion for treatment of Pediculus humanus var capitis infestation.

One hundred fifteen subjects took part in a double-blind study comparing the efficacy and safety of 0.5% malathion lotion (Prioderm lotion) and the alcoholic vehicle of the lotion as pediculicides in the treatment of head lice. The subjects, with a mean age of 9 years, had long-standing lice infestations and at least 20 viable ova. The subjects were treated with the test preparation, which was allowed to remain on the hair for 12 hours. Ovicidal and pediculicidal efficacy for the malathion lotion was significant; overall clinical evaluation by the investigators showed a significant number of moderate to marked therapeutic responses to malathion lotion. Only one adverse reaction (in the malathion lotion group) was reported, the stinging of pyodermal lesions in reaction to the alcoholic vehicle. Other concomitant scalp diseases were unchanged or improved at the end of the study.

Administration, Topical↗