NAD(P)H: quinone oxidoreductase 1 expression in human bone marrow endothelial cells

NAD(P)H:quinone oxidoreductase 1 (NQO1) participates in the detoxification of many environmental quinones and related compounds. Recent studies have suggested that individuals with a polymorphism in NQO1 (NQO1*2), which results in a decrease (heterozygous, NQO1*1/*2) or a total loss (homozygous, NQO1*2/*2) of NQO1, may be at increased risk for the development of leukemias. Previous studies have failed to detect NQO1 in freshly aspirated bone marrow including Ficoll-purified mononuclear cells and purified CD34(+) hematopoietic progenitor stem cells. In these studies we examined human bone marrow core biopsies by immunohistochemistry using monoclonal antibodies directed against NQO1. These studies revealed that NQO1 was expressed in human bone marrow but expression of NQO1 was limited to bone marrow endothelium and adipocytes. To confirm the expression of NQO1 in bone marrow endothelial cells we examined an immortalized human bone marrow endothelial cell line (HBMEC-60) for NQO1 protein expression. Immunoblot analysis and an activity assay confirmed the expression of NQO1 in HBMEC-60. These data demonstrate that NQO1 is present in human bone marrow. The increased risk of leukemia associated with a deficit in NQO1 levels due to the NQO1*2 polymorphism may reflect impaired quinone detoxification and an increased susceptibility of endothelial cells in bone marrow to environmental insults.

Patterns of telephone use among nursing home residents

There is convincing evidence that nursing home residents who have more visitors fare better than those who have fewer visitors. However, as many as one third of all individuals living in nursing homes have virtually no visitors. The purpose of this study was to address this concern by examining telephone use in older adults living in nursing homes, and evaluating the potential of telephone communications as a means of social support for this at-risk group. Using a recording device activated each time the receiver was picked up, the research team "listened in" on the telephone conversations of three nursing home residents (aged 76, 79, and 92) for a period of 1 week. The transcripts revealed 56 minutes of actual conversation during the week (10, 21, and 25 minutes, respectively), most often with family or longtime friends living out of town. Each resident laughed aloud more than once per minute. The telephone conversations provided the residents with vivid glimpses of life outside the walls of their facility and appeared to help them stay connected with their family and friends. The findings support further study of the telephone as a way to sustain authentic social support in long-term care populations.

Ex vivo expanded peripheral blood progenitor cells provide rapid neutrophil recovery after high-dose chemotherapy in patients with breast cancer

Ex vivo expanded peripheral blood progenitor cells (PBPCs) have been proposed as a source of hematopoietic support to decrease or eliminate the period of neutropenia after high-dose chemotherapy. CD34 cells were selected from rhG-CSF mobilized PBPCs from patients with breast cancer and were cultured for 10 days in defined media containing 100 ng/mL each of rhSCF, rhG-CSF, and PEG-rhMGDF in 1 L Teflon bags at 20 000 cells/mL. After culture the cells were washed and reinfused on day 0 of transplantation. On day +1, cohort 1 patients (n = 10) also received an unexpanded CD34-selected PBPC product. These patients engrafted neutrophils (absolute neutrophil count, >500/microL) in a median of 6 (range, 5-14) days. Cohort 2 patients (n = 11), who received expanded PBPCs only, engrafted neutrophils in a median of 8 (range, 4-16) days. In comparison, the median time to neutrophil engraftment in a historical control group of patients (n = 100) was 9 days (range, 7-30 days). All surviving patients are now past the 15-month posttransplantation stage with no evidence of late graft failure. The total number of nucleated cells harvested after expansion culture was shown to be the best predictor of time to neutrophil engraftment, with all patients receiving more than 4 x 10(7) cells/kg, engrafting neutrophils by day 8. No significant effect on platelet recovery was observed in any patient. These data demonstrate that PBPCs expanded under the conditions defined can shorten the time to engraftment of neutrophils compared with historical controls and that the rate of engraftment is related to the dose of expanded cells transplanted.

Insulin signaling and glucose transport in insulin resistant skeletal muscle. Special reference to GLUT4 transgenic and GLUT4 knockout mice

Glucose homeostasis is impaired in patients with non-insulin dependent diabetes mellitus (NIDDM) and this defect in due in part, to defects in glucose transport in skeletal muscle. Intense interest is now focused on whether reduced insulin-mediated glucose transport in muscle from NIDDM patients results from alterations in the insulin signal transduction pathway or from alterations in traffic and/or translocation of GLUT4 to the plasma membrane. Recently, potential targets for impaired traffic/translocation of GLUT4 have been reported to include defective phosphorylation of IRS-1 and reduced PI-3 kinase activity. In addition to insulin signaling defects, impaired glucose transport may result from a defect(s) in the activation or functional capacity of GLUT4. Because GLUT4 is dysregulated in skeletal muscle from NIDDM patients, it is an attractive target for gene therapy. Overexpression of GLUT4 in muscle results in increased glucose uptake and metabolism, and protects against the development of insulin resistance in transgenic mice. Genetic ablation of GLUT4 results in impaired insulin tolerance and defects in glucose metabolism in skeletal muscle. Because impaired muscle glucose transport leads to reduced whole body glucose uptake and hyperglycemia, understanding the molecular regulation of glucose transport in skeletal muscle is necessary to develop effective strategies to prevent or reduce the incidence of NIDDM.

Dynamic Recovery: comparative study of therapeutic communities in homeless shelters for men

The Dynamic Recovery Project examined relationships between homelessness, substance abuse, and recovery, and investigated the effectiveness of the therapeutic community (TC) treatment model in helping homeless drug users move toward stable, drug-free living. This project compared two short-term TCs that were situated within pre-existing homeless shelters with a clean and sober dormitory. In a separate condition, peer counselors and staff were provided additional training in TC philosophy and practice to reduce program dropout. Dramatic decreases in drug and alcohol use at follow-up were verified by urinalysis. Length of time in treatment rather than specific program accounted for decreased alcohol and drug use. Important decreases in posttreatment criminality for both treatment programs were documented. The comparison group, starting with low criminality, experienced smaller, nonsignificant decreases unrelated to type of program or time in treatment. Major declines in Beck Depression Scores were evident, but were unrelated to groups or time in treatment. Training had no measurable impact on client retention or outcomes and there were no significant differences between TCs and the comparison group on posttreatment drug use, criminality, or depression. This report documents that short-term therapeutic communities can be successfully implemented in public shelters for homeless men.

Overexpression of human stem cell factor impairs melanocyte, mast cell, and thymocyte development: a role for receptor tyrosine kinase-mediated mitogen activated protein kinase activation in cell differentiation

Stem cell factor (SCF) is synthesized as both soluble (S) and membrane-associated (MA) proteins. Indirect insight into the function of MA and S isoforms of SCF has come from studies performed in Steel (Sl) mutant mice. However, the physiologic role(s) of these two isoforms remain unknown. In an attempt to better understand the in vivo role of c-kit/SCF interactions on various cell lineages, transgenic mice were generated that overexpress MA isoform of human SCF (hSCF). In murine cells, hSCF behaves as an antagonist to normal SCF function, due to interference with the interaction between endogenous murine SCF and its receptor, c-kit, encoded by the dominant white spotting (W) gene. Mice expressing the hSCF transgene display a variety of phenotypic abnormalities, which are accentuated when combined with W alleles. Here we show that mice homozygous for the hSCF transgene demonstrate a coat color deficiency seen in some mice homozygous for mild W alleles. Specifically, homozygous hSCF transgenic mice (hSCF220) display a pronounced forehead blaze, with additional white spots over the cervical region, as well as a very large belly spot. Doubly heterozygous animals that carry both a mutated W allele and the hSCF transgene also display an unusual pigment defect and a dramatic reduction in the number of dermal mast cells. Furthermore, overexpression of MA hSCF in the thymus results in abnormal thymocyte differentiation and proliferation, which is associated with reduced mitogen activated protein (MAP) kinase activation. Thus, MAP kinase activation by a receptor tyrosine kinase, such as c-kit, may be critical for the differentiation of thymocytes in vivo.

Gating strategy for immunophenotyping of leukemia and lymphoma

Clinical specimens of blood, bone marrow, lymph node, extranodal tissue, and body fluid were collected from 67 cases of hematologic neoplasms (including chronic lymphoid leukemias, T- and B-cell lymphomas, and acute lymphoblastic and myelogenous leukemias) for comparison between the right-angle light scatter (RALS)/CD45 and the forward-angle light scatter (FALS)/RALS gating combinations. One to three diagnostic markers were selected from each case, yielding 124 paired results for comparison. We found that the percentage of tumor cell isolation and the total cell count in the tumor cell gate were higher in RALS/CD45 than in FALS/RALS. When 20% was used as a cutoff point, 30 markers in FALS/RALS failed to identify the tumor population, while only 3 markers in RALS/CD45 failed to do so. The discriminative factor in the RALS/CD45 gating was mainly the CD45 intensity, whereas all cases except 3 showed low RALS. Although T-cell neoplasms showed a higher proportion of high CD45 intensity, other groups shared similar ranges of CD45 intensity, which is therefore of limited value for differential diagnosis. The RALS/CD45 combination produces higher recovery and purity for tumor cell isolation than the FALS/RALS combination and should replace the latter for routine immunophenotyping of lymphoma and leukemia.

The effect of chemical modification of basic amino acid residues on the activation and amidolytic activity of Hageman factor (factor XII)

Modification of arginyl residues of Hageman factor by phenylglyoxal hydrate inhibits activation of this clotting factor in a plasma-free system, that is, in the absence of the other constituents of the contact activation system. Activation is also inhibited by alteration of the other two basic amino acid residues present, lysine and histidine. Chemical modification of histidine and arginine residues does not inhibit the amidolytic activity of activated Hageman factor. In contrast, modification of amino group(s) in N-terminal and lysine residues inhibits activated Hageman factor. Thus, basic amino acid residues essential to the activation or activity of Hageman factor appear to be variably accessible to chemical modification.

Hematologic, serologic values, histopathologic and fecal evaluations of bison from Yellowstone Park

Hematologic and blood chemistry parameters were measured in 149 free-ranging American bison (Bison bison) from Yellowstone National Park, Wyoming (USA). Additionally, histopathologic evaluations of lung, liver, spleen, kidney, and mesenteric and bronchial lymph nodes were made from ten animals. Forty-five fecal samples were screened for the presence of helminth ova. Leukopenia and markedly low blood urea nitrogen concentrations were the most notable differences observed from other bison populations. All tissues examined were essentially normal; there was evidence of moderate intestinal parasite burdens.

Brain-stem auditory evoked responses in 56 patients with acoustic neurinoma

The brain-stem auditory evoked responses (BAER's) recorded from 56 patients with acoustic neurinomas were analyzed. Ten of the patients had intracanalicular tumors and 46 had extracanalicular tumors. It was possible to obtain BAER's following stimulation of the affected side in 28 patients and after stimulation of the unaffected side in all 56. Five patients (11%) had normal BAER's following stimulation of both sides; three of these patients had intracanalicular tumors. Among BAER's obtained following stimulation of the affected ear, the mean interpeak latency (IPL) for peaks I to III associated with extracanalicular tumors was significantly prolonged relative to controls (p less than 0.001), and linear regression analysis revealed a significant positive correlation between tumor size and IPL of peaks I to III (p less than 0.05). Analysis of the 56 BAER's recorded after stimulation of the unaffected side revealed a significant positive correlation between the IPL's of peaks III to V and tumor size (p less than 0.001). This correlation was not strengthened when accounting for the degree of brain-stem compression. Finally, evidence of preserved function within the auditory pathway, even in the presence of partial hearing loss, is presented. This finding suggests that more patients might benefit from surgical procedures that spare the eighth cranial nerve.

Motor evoked potentials elicited from pyramidal stimulation and recorded from the spinal cord in the rat

This study investigated the spinal evoked response to focal electrical stimulation of the sensorimotor cortex in 32 rats. The results demonstrate a long-latency response (beginning at 8 milliseconds) elicited by electrical stimulation, which is distinct from the short-latency motor evoked potential previously reported. The conduction velocity of this later response is similar to that reported for the pyramidal tract in the rat. Experiments confirm that the longer latency response depends upon the integrity of the pyramidal system. Focal stimulation outside the sensorimotor cortex failed to elicit a response. Experimental lesions of the pyramidal tract or ablating the sensorimotor cortex eliminated the spinal cord evoked response. The results demonstrate that focal stimulation of the sensorimotor cortex results in a spinal cord evoked response that represents activity within the pyramidal system. The utility of this response in the rat model for assessing experimental cord injury is discussed.

The patients' view of life in a psychiatric hospital. A questionnaire study and associated methodological considerations

In any assessment of hospital life, the patients' view is indispensable, but there is no generally accepted way of seeking it. In this study, the views of 258 patients in four 'traditional' English psychiatric hospitals were obtained by a questionnaire of 45 items supplemented by freehand comments. Their experience of fellow patients, the staff and the material and institutional aspects of hospital care were explored. Some of the benefits and problems of questionnaire use in this realm are discussed.

Effects of selective spinal cord lesions on the spinal motor evoked potential (MEP) in the rat

The effects of selective spinal cord lesions on the motor evoked potential (MEP) in 21 rats were investigated. No significant change in peak amplitude was observed following lesions of the pyramidal tract. There was a significant decrease in peaks 1 and 2 with ventral funiculi lesions. All 4 peaks of the MEP were significantly reduced following lesions of the lateral funiculus. The most marked decrease in peak amplitude followed lateral funiculi lesions that involved the lateral grey of the spinal cord. In one animal where the lesion was confined to the grey matter in the cord there was a marked decrease in all peaks of the MEP. In 3 additional animals interruption of the descending tracts of the spinal cord via bilateral hemisections of the spinal cord failed to completely abolish the MEP. Increases in peak latency were also noted following spinal lesions. In some animals the increase in latency occurred in the absence of significant peak amplitude changes. The findings in this study refute the previously held position that the MEP in the rat arises from pyramidal tract activation. The role of the reticulospinal and propriospinal tracts in the generation and propagation of the MEP are discussed.

Noncortical origins of the spinal motor evoked potential in rats

Motor evoked potentials (MEPs) were recorded from the spinal cord, sciatic nerve, or both during transcortical electrical stimulation in the rat. Four peaks could be consistently identified in the spinal MEP. The latency and amplitude of the peaks varied differentially with intensity and polarity of stimulation. Conduction velocity for Peak 1 of the MEP was 43 m/sec. Bilateral sciatic nerve MEPs were present after unilateral cortical stimulation. The spinal MEP was elicited by stimulation of areas outside the motor cortex, and the response persisted during subcortical stimulation and after motor cortex ablation. We present evidence suggesting that components of the spinal MEP in rats arise from pathways outside the motor cortex.

Interictal behaviour in hospitalised temporal lobe epileptics: relationship to idiopathic psychiatric syndromes

Temporal lobe epileptics undergoing psychiatric hospitalisation were contrasted with patients suffering idiopathic psychiatric syndromes or other epilepsies. Quantitative ratings from blind interviews conducted according to a protocol confirmed the appearance of a statistically distinctive behavioural profile, including the desire for social affiliation, circumstantiality, religious and philosophic interests, and deepened affects, among the temporal lobe epileptics.