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Biomedical subjects

B Kaufman

Publications and source records attributed to B Kaufman.

At least 55 records · Page 3Linked to original sources
PubMed1993

Varied microcirculation of pituitary adenomas at rapid, dynamic, contrast-enhanced MR imaging.

PURPOSE: Rapid, dynamic, contrast material-enhanced magnetic resonance imaging was performed to evaluate the early enhancement patterns of normal pituitary structures, macroadenomas, and microadenomas. MATERIALS AND METHODS: A 1.5-T imager with a circularly polarized head coil was used on 40 patients referred for investigation of endocrinopathy, of neurologic deficit, or for follow-up of a previously documented pituitary tumor. RESULTS: The technique provided a temporal resolution of one image per 1.25 seconds, allowing discrimination of primary arterial and secondary portal circulation enhancement phases of pituitary structures and tumors. Arterial-phase enhancement of 16 macroadenomas was observed, suggesting a primary arterial blood supply to these lesions. Five microadenomas showed minimal enhancement in the secondary portal circulation phase. A brief temporal phase was also captured, in which cavernous sinus invasion by tumor was visualized as a "filling defect" within the gadolinium-laden laterosellar venous spaces. CONCLUSION: The technique reveals the microcirculatory dynamics associated with pituitary adenomas and suggests a dominant arterial blood supply for macroadenomas. It can supplement routine spin-echo imaging for determination of cavernous sinus invasion. Limitations related to section positioning, resolution, and signal-to-noise ratio exist.

Adenoma↗
PubMed1993

Infections following nail puncture wound of the foot: case reports and review of the literature.

Between July 1989 and August 1990, five children (four boys and one girl, age 10-14 years) were hospitalized due to foot infection following nail puncture wound. Symptoms and signs at presentation included cellulitis and deep tissue abscess in all five, fever in three, high erythrocyte sedimentation rate in four, and leukocytosis in two patients. Pseudomonas aeruginosa was grown in pus culture that was taken from all the children at presentation. In three children who were initially treated by local debridement and drainage followed by anti-pseudomonal agents, plantar Pseudomonas osteochondritis later developed. In two children extensive debridement of affected tissues and drainage of pus were performed followed by 2 weeks of parenteral anti-Pseudomonas antibiotics. No further complication occurred. The clinician should be aware that any complication of nail puncture wound of the foot may require surgery.

Abscess↗
PubMed1992

Health care reform issues call for plain talk.

Getting the health care reform message out to your community is vital, writes the author, but learning how to communicate that message is equally critical. To do that, he says, you must know your audience, establish common ground with as many people as possible, and say what you have to say in language they can understand. The media filter, he says, poses a persistent challenge to communicating the issue.

Attitude to Health↗
PubMed1992

Neuroblastoma. Effect of genetic factors on prognosis and treatment.

BACKGROUND AND METHODS. Genetic analysis of tumor tissue has provided considerable insight into mechanisms of malignant transformation and progression. Neuroblastomas have been studied by cytogenetics, flow cytometry, and molecular genetic techniques, and these studies have identified several specific abnormalities that allow subclassification of these tumors into genetic/clinical subtypes. RESULTS AND DISCUSSION. Four genetic abnormalities have been identified that are characteristic of certain neuroblastomas. These include: (1) loss of heterozygosity (LOH) for the short arm of chromosome 1, including band 1p36; (2) amplification of the N-myc protooncogene; (3) hyperdiploidy, or near triploidy; and (4) defects in expression or function of the nerve growth factor receptor (NGFR). Abnormalities of the NGFR are found in virtually all neuroblastoma cell lines, and some primary tumors. The latter have not been studied extensively. Hyperdiploidy is associated with lower stages of disease and with a favorable outcome in infants. LOH for chromomors. The latter have not been studied extensively. Hyperdiploidy is associated with lower stages of disease and with a favorable outcome in infants. LOH for chromosome 1, band p36, and N-myc amplification are more common in patients older than 1 year of age with advanced stages of disease. The latter two genetic abnormalities may be related, and LOH for 1p36 may precede the development of amplification. When these abnormalities are combined with assessment of DNA content, three distinct genetic subsets of neuroblastomas can be identified. The first is characterized by a hyperdiploid or near-triploid modal karyotype, with few if any cytogenetic rearrangements. These patients generally are younger than 1 year of age with localized disease and a good prognosis. The second has a near-diploid karyotype, with no consistent abnormality identified currently. These patients generally are older with more advanced stages of disease that progress slowly and are often fatal. The third group has a near-diploid or tetraploid karyotype, with deletions or LOH for 1p36, amplification of N-myc, or both. These patients generally are older with advanced stages of disease that rapidly are progressive. Thus, genetic analysis of neuroblastoma cells provides information that has prognostic significance and can direct a more appropriate choice of treatment.

Cell Line↗
PubMed1992

Gene flow by immigrants into isolated recipient populations: a laboratory model using flour beetles.

The effectiveness of immigrants as agents of gene flow was investigated in a laboratory model, using mutant marker strains of the flour beetle, Tribolium castaneum (Herbst). We show that immigrants had an advantage over residents. The proportion of hybrid offspring (PHO), resulting from immigrant mating with residents, was higher than expected from their frequency in the parental population. This advantage was observed regardless of immigrant sex and immigrant strain. The advantage seems to result from immigrant mating advantage (although not a rare-male phenomenon) and not from better survival of hybrid offspring. However, hybrid offspring seem to be more resistant to sporozoan infection, resulting in higher PHO in sporozoan-infected cultures.

Animals↗
PubMed1991

Protection against tetrodotoxin and saxitoxin intoxication by a cross-protective rabbit anti-tetrodotoxin antiserum.

A tetrodotoxin-formaldehyde-keyhole limpet hemocyanin conjugate was used to immunize a rabbit for the production of anti-toxin antiserum. The antiserum cross-reacted against both tetrodotoxin (TTX) and saxitoxin (STX), and in a quantitative in vitro assay was able to protect cells in a dose-dependent manner from the effects of either TTX or STX. The antiserum was also able to passively protect mice challenged in vivo with either toxin. Hybridomas producing monoclonal antibodies against toxin were obtained from the spleens of mice immunized with the same conjugate.

Animals↗
PubMed1991

Continuous epidural methadone treatment for cancer pain.

Seventy cancer patients suffering from visceral or somatic pain received continuous epidural methadone (EM) analgesia. Initially, 4 mg of 0.1% methadone was given three times daily. If this dose proved ineffective, it was gradually increased to 8 mg four times daily. With this regimen good pain control was obtained in 56 patients (80%). Patients continued the EM therapy for periods up to 140 days, with an average duration of 27 days. Morphine was substituted for methadone in 14 patients (20%). Four of these patients responded well and continued treatment for an average of 18 days. No serious side effects have been observed with EM. With a proper selection of patients and following strict therapy guidelines, epidural methadone is efficacious in treating cancer pain.

Adolescent↗
PubMed1990

Neutral and acidic human tracheobronchial mucin. Isolation and characterization of core protein.

Human bronchial mucin from a patient suffering from chronic bronchitis was solubilized in aqueous solution containing sodium azide and protease inhibitors and purified by Sepharose 4B and 2B column chromatography. The mucin was further purified by cesium bromide density gradient centrifugation. Sodium dodecyl sulfate-polyacrylamide gel (7.5%) electrophoresis of this material showed high-molecular-weight mucin component(s) at the top of the gel. Chemical analysis of this preparation indicated a typical mucin profile of amino acids and carbohydrates. Ion-exchange chromatography resulted in resolution of the purified mucin into neutral and acidic fractions. Comparison of the chemical composition of these two fractions showed higher mole percentage of threonine, serine, sialic acid, and sulfate in the acidic fraction. Chemical deglycosylation of the purified mucin preparation with trifluoromethane sulfonic acid was carried out at 20 degrees C for 3 1/2 h. Sialic acid, fucose, galactose, and N-acetylglucosamine were completely removed, whereas traces of N-acetylgalactosamine were still detected. High-pressure liquid chromatography of the deglycosylated products from native, neutral, and acidic mucin preparations resulted in a principal peptide, P1, with identical amino acid composition. Cyanogen bromide (CNBr) treatment of the peptide P1 from neutral and acidic mucins and subsequent fractionation of the fragments by high-pressure liquid chromatography resulted in similar peptide profiles. The P1 peptide fraction was further subjected to high-pressure liquid chromatography in a second solvent system, which resulted in two peaks, P1a and P1b. Gel filtration of both peptides in 6 M guanidine hydrochloride indicated a single peak with molecular weight of approximately 97 kDa. The amino acid profile of the two peptides was dominated by high levels of threonine, serine, and proline, which combined accounted for nearly 39% of the total residues, and in most respects, the profile resembled that of native mucin. End-group analysis of the peptide P1a indicated a blocked N-terminus, whereas serine was found to be the N-terminal amino acid in the peptide P1b. Rabbit antibodies prepared against the peptide P1 from native tracheal mucin reacted strongly with neutral and acidic mucin as well as the mucin from human colon. Both neutral and acidic human tracheal mucins were immunologically reactive with mouse monoclonal antibody HMPFG-2, which was prepared against human mammary mucin. However, the response of this antibody to human colonic mucin was rather weak.

Amino Acids↗
PubMed1990

Cell wall structures which may be important for successful immunization with Salmonella-Shigella hybrid vaccines.

Three separate lots of S. typhi/S. sonnei hybrid (Ty/Shig) live oral vaccine strain 5076-1C were tested for efficacy in human volunteers challenged with virulent S. sonnei. Two lots (2 and 5) protected volunteers, a third lot (8) did not. The three lots were evaluated by immunological tests and electron microscopy. Lots 2 and 5, which protected, contained bacteria that reacted with anti-flagellar serum and had observable attached flagella and pili. Lot 8, which failed to protect, did not react with anti-flagellar serum, and had no observable pili. There was no correlation between vaccine efficacy and the reaction of IgG in patient's sera in western blot analysis. Surface structures on the Ty-Shig hybrid may be important for generating a protective immune response.

Animals↗
PubMed1990

Prolonged course of a cutaneous T-cell lymphoma with late systemic involvement.

The clinical course of cutaneous T-cell lymphomas is known to be extremely variable. The disease may be present for up to 50 years, although it has a median survival of four to ten years. Clinical manifestations may range from cutaneous involvement alone to widespread systemic involvement. Described here is a patient with an unusually prolonged course of a cutaneous T-cell lymphoma with systemic involvement which reappeared ten and 18 years after the initial presentation. The patient developed Sjögren's syndrome, bone marrow and peripheral nerve involvement late in the course of her disease.

Adult↗
PubMed1989

Proteolytic fragmentation and peptide mapping of human carboxyamidomethylated tracheobronchial mucin.

Human tracheobronchial mucin was isolated from lung mucosal gel by chromatography on Sepharose 4B in the presence of dissociating and reducing agents, and its thiol residues were carboxyamidomethylated with iodo[1(-14)C]acetamide. The 14C-carboxyamido-methylated mucin was purified by chromatography on Sepharose 2B. No low molecular weight components were detected by molecular sieve chromatography or polyacrylamide gel electrophoresis in the presence of dissociating and reducing agents or by analytical density centrifugation in CsCl/guanidinium chloride. After digestion of the purified 14C-mucin with trypsin-L-1-tosylamido-2-phenylethyl chloromethyl ketone, three fractions (TR-1, TR-2, and TR-3) were observed by chromatography on Sepharose 4B. TR-1, a 260-kDa mucin glycopeptide fragment, contained all of the neutral hexose and blood group activity and 20% of the radioactivity in the undigested mucin. TR-1 was refractory to a second incubation with trypsin but could be digested by papain or Pronase to a smaller mucin glycopeptide fraction, as judged by the slight decrease in apparent molecular weight on Sepharose CL-4B. These mucin glycopeptides contained approximately 50% of the radioactivity in the TR-1 fraction, indicating that the glycosylated domains of carboxyamidomethylated tracheobronchial mucin contained thiol residues. The remainder of the radioactivity from papain or Pronase digests of TR-1 eluted, like the TR-3 fractions, in the salt fraction on Sepharose CL-4B. Peptide mapping of the nonglycosylated TR-3 fraction by TLC and high voltage electrophoresis yielded six principal and several less intensely stained ninhydrin reactive components, with the radiolabel concentrated in one of the latter peptides. Peptide purification of the TR-3 fraction by high pressure liquid chromatography on a C18 reverse phase column demonstrated the presence of four major peptides, with TR-3A being the dominant component. The TR-3D peptide contained S-carboxy-aminomethylcysteine and had 69% sequence similarity to the sgs-7 salivary glue protein of Drosophila.

Amino Acids↗