A case of arsenic intoxication presenting as a myelodysplastic syndrome is reported. A 41-year-old woman with a 6-month history of gastrointestinal and neurological symptoms was noted to be pancytopenic at presentation. A bone marrow aspirate revealed dysmyelopoietic changes involving all three marrow cell lines. Subsequent analysis of urine for heavy metals demonstrated very high levels of arsenic. Treatment with British anti-Lewisite (BAL) resulted in the resolution of gastrointestinal symptoms and hematological abnormalities although the neurological complications progressed. This case emphasizes that heavy metal intoxication should be considered in the differential diagnosis of any individual presenting with the hematological features of myelodysplasia especially when accompanied by clinical features considered atypical for primary or secondary myelodysplasia.

Adult↗

PubMed1991

Effects of topical suprofen and flurbiprofen on the miosis produced by anterior chamber irrigation with cholinergic agonists.

Pretreatment with topical nonsteroidal anti-inflammatory drugs is common practice to maintain maximal pupil dilation for cataract surgery. Most surgeons also inject a cholinergic agent intracamerally for miosis after intraocular lens insertion. We evaluated the effects of topical suprofen and flurbiprofen on the miosis induced by anterior chamber irrigation with either acetylcholine or carbachol. One eye of 30 pigmented rabbits was dilated with cyclopentolate HCl and phenylephrine HCl. Three groups, each composed of ten eyes, received flurbiprofen, suprofen, or a control. In each group, five eyes received acetylcholine by anterior chamber irrigation and five received carbachol. Pupil diameters were measured with calipers before and five minutes after irrigation by an observer unaware of the treatment regimen. Irides irrigated with carbachol constricted less than those irrigated with acetylcholine (P = .016). In anterior chambers irrigated with carbachol, suprofen was associated with less miosis than either tears (P = .005) or flurbiprofen (P = .009); however, if the infusion was performed with acetylcholine, no differences between the three groups were noted (P = .44).

Acetylcholine↗

PubMed1991

Immunocytochemical analysis of estrogen and progesterone receptors in benign stromal lesions of the breast. Evidence for hormonal etiology in pseudoangiomatous hyperplasia of mammary stroma.

Five cases of pseudoangiomatous hyperplasia of mammary stroma, together with seven examples of mammary hamartoma, were probed with monoclonal antibodies H222 and KD68 to investigate the possible role of estrogen and progesterone receptor expression in the pathogenesis of these benign stromal proliferations. All five cases of pseudoangiomatous hyperplasia showed patchy, intense labelling of the stromal cells with progesterone receptor antibodies, a pattern contrasting markedly with the absence of immunoreactivity in normal (nongestational) mammary stroma or the stromal component of common juvenile mammary hyperplasia. The stroma of the hamartoma group labeled inconsistently, with the notable exception of three myoid hamartomas. Stromal immunoreactivity was diffuse and intense in two of these, and patchy and distinct in the remaining case. These findings (a) support the contention that pseudoangiomatous hyperplasia represents a localized form of stromal overgrowth with a hormonal (primarily progestagenic) etiology and (b) further highlight the heterogeneity of so-called mammary hamartomas by demonstrating dramatically different progesterone receptor immunoreactivity patterns in myoid lesions as compared with other hamartoma variants.

Adult↗

PubMed1991

The effect of tarsorrhaphy on normal healing of corneal epithelial defects in a rabbit model.

The presumed benefits of occlusive patching are patient comfort and enhancement of corneal healing. However, there is little experimental evidence to document a beneficial effect of eyelid occlusion on corneal healing. We produced corneal abrasions by mechanical debridement within a 4 mm trephine-marked area on 1 eye each of 23 New Zealand albino rabbits. Homatropine 5% solution and erythromycin ointment were instilled. Then we divided the animals into three groups. The abraded eyes of the first group (7 rabbits) were sutured shut by a temporary tarsorrhaphy. The eyes of the second group (7 rabbits) were left open until 12 h postinjury, when they were sutured shut in a similar fashion. The abraded eyes of the control group (9 rabbits) were left open for the entire observation period. We monitored fluorescein staining patterns of the epithelial defects photographically at a set focal length at 12-h intervals. By 48 h, corneal staining had resolved in 87% of eyes. We performed computerized planimetry on the photographs of wound size for each time point. There was no statistically significant difference in the rate of healing of corneal abrasions in the occluded versus of the unoccluded eyes.

Animals↗

PubMed1991

A canine model of paired graft thrombosis.

A novel canine model for reliably producing graft thrombosis is described. Two unilateral aortoiliac bypasses are performed while preserving the integrity of the native vascular tree. These grafts are briefly mechanically occluded at the time of the initial operation, and they remain occluded postoperatively because flow is preferentially directed through the larger-caliber, thrombo-resistant native circulation. Percutaneous temporary intra-arterial balloon occlusion of the native vessels redirects flow into the occluded graft segments, which can be used in experimental protocols. This new model for studying graft thrombosis requires only a single, simple operative procedure, and easily allows secondary percutaneous graft manipulation.

Animals↗

PubMed1991

Isolation and molecular characterization of spontaneously occurring cytolysin-negative mutants of Actinobacillus pleuropneumoniae serotype 7.

Actinobacillus pleuropneumoniae serotype 7 strains are shown to spontaneously lose cytolytic activity with a frequency of approximately 10(-4). The phenotypic change is associated with the loss of approximately 8.5 kbp of chromosomal DNA. A genomic fragment encoding the cytolysin and its flanking sequences was cloned and characterized. Also, the corresponding truncated fragment was cloned from a spontaneous mutant. Comparison of the two clones allowed the definition of the excision site. The ends of the excised fragment are composed of 1,201 bp long direct identical repeats, possibly facilitating the genotypic change by homologous recombination. In accordance with this hypothesis, one repeat is conserved in the spontaneous mutant. Each repeat contains one open reading frame preceded by a Shine-Dalgarno consensus sequence, and the ends of each repeat contain 26-bp complementary sequences with four mismatches.

Actinobacillus pleuropneumoniae↗

PubMed1991

The NPEY sequence is not necessary for endocytosis and processing of insulin-receptor complexes.

The tetrameric amino acid sequence AsnProXTyr (NPXY), where X represents any amino acid, is conserved in the intracytoplasmic domains of several membrane proteins and has been postulated to play a role in receptor-mediated endocytosis. The human insulin receptor (hIR) contains a single copy of the sequence AsnProGluTyr (NPEY) in its intracytoplasmic domain. To determine if this putative consensus sequence is necessary for endocytic functions of hIR, we constructed a mutant receptor, hIR delta NPEY, that lacks NPEY sequence, stably expressed this mutant receptor in Chinese hamster ovary cells, and then studied its endocytic functions. When compared to wild type hIR similarly expressed in Chinese hamster ovary cells, the hIR delta NPEY mutant exhibited: 1) normal subunit organization and insulin binding affinity; 2) essentially normal internalization of covalent photoaffinity labeled insulin-receptor complexes; and 3) normal internalization of receptor-bound [125I]insulin as well as normal degradation and release of the internalized insulin. Therefore, we conclude that the NPEY sequence in the juxtamembrane domain of hIR is not necessary for its endocytic function.

Amino Acid Sequence↗

PubMed1991

Motorcycle licensure, ownership, and injury crash involvement.

The interrelationships among motorcycle licensure, ownership, and injury crash involvement were investigated in a sample of 2,723 motorcycle drivers severely or fatally injured in California in 1985-86. Owners of motorcycles in such crashes ("driver-owners") were less likely to have valid licenses than a random sample of motorcycle owners who had not been in crashes (42 vs. 57 percent). Thirty-three percent of the crash-involved drivers had valid motorcycle driver's licenses; 39 percent were operating motorcycles they did not own ("driver-nonowners"). Driver-nonowners were less likely to be validly licensed than driver-owners (20 percent vs. 44 percent). The licensing rate of crash-involved driver-nonowners was 15 percent if the owner was also unlicensed. Rates of valid licensure were lowest among the youngest drivers. Virtually no crash-involved driver-nonowners under age 21 were licensed in cases in which the owner was also young and unlicensed.

Accidents, Traffic↗

PubMed1991

Ethanol absorption across human skin measured by in vivo microdialysis technique.

Microdialysis, a new bioanalytical sampling technique enables measurement of substances in the extracellular space. This initial study investigates the technique's usefulness in the field of percutaneous absorption of solvents, using ethanol as test substance. Microdialysis probes are equipped at the tip with a semi-permeable polycarbonate membrane which permits passive diffusion of substances. Ethanol does not damage the membrane. In vitro recovery for ethanol is good. Probes were inserted via a guide into the skin of the ventral forearm in 7 volunteers. 99.5% ethanol was applied to the skin in excess in a glass reservoir. The probe was perfused at a flow of 1 microliter/min. 50 microliters samples were analysed by gas chromatography. Absorption of ethanol was demonstrated in all subjects. Values from the 9 probes inserted ranged from 10 micrograms/ml to 800 micrograms/ml. The variation may be explained by inter-test or inter-individual variability in ethanol absorption. Individual metabolic capacity may be of importance. The method opens new possibilities in the investigation of skin barrier function in man.

Chromatography, Gas↗

PubMed1991

Clinical presentations of stroke: the classic and the less obvious.

While there are several types of stroke, the sudden or rapidly developing loss of one or more cerebral functions is the hallmark of the condition. Although classic manifestations include hemiparesis, hemianaesthesia, hemianopia, dysphasia, ataxia and cranial nerve palsies, several less typical stroke syndromes occur regularly.

Cerebrovascular Disorders↗

PubMed1991

Methods in pathology. Identification of T-cell lymphomas in paraffin-embedded tissues using polyclonal anti-CD3 antibody: comparison with frozen section immunophenotyping and genotypic analysis.

While L26 (CD20) is now well established as a B-cell marker of high specificity for use in paraffin-embedded tissues, paraffin-reactive T-cell antibodies (UCHL1, MT1, Leu-22, DF-T1, and MT2) have not shown comparable lineage specificity. A new commercially available polyclonal antibody directed against a synthetic peptide sequence of the CD3 (T-cell) antigen has recently become available for use on paraffin sections. In order to evaluate the utility of this antibody, we studied CD3 expression in conjunction with L26 and leukocyte common antigen (LCA) in 15 T-cell and 20 B-cell non-Hodgkin's lymphomas (NHL), all genotypically confirmed by DNA hybridization and immunophenotyped by immunoperoxidase studies in frozen tissue. Ten of 15 T-cell NHLs (67%) showed unequivocal immunolabeling of neoplastic cells with anti-CD3 in paraffin-embedded tissue. Of the five negative cases, three were lymphoblastic lymphomas, and two were peripheral (postthymic) lymphomas (one anaplastic large cell, Ki-1 positive and one large cell, immunoblastic). CD3 expression was identical in paraffin and cryostat sections (100% concordance). Twenty of 20 B-cell NHLs were positive with L26 and LCA but were negative with anti-CD3. Other neoplasms examined, including three granulocytic sarcomas and 45 nonhematopoietic tumors, were similarly negative with anti-CD3. We conclude that polyclonal anti-CD3 is a sensitive and highly specific T-cell marker in paraffin-embedded tissue and, when used in conjunction with LCA and L26, that it can determine cell lineage in the majority of non-Hodgkin's lymphomas.

Antigens, CD↗