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101.
We describe a new rat immunoglobulin M monoclonal antibody (CH-F42) that recognizes a subset (1.5% to 8%) of normal peripheral blood T lymphocytes. The phenotype of these cells was determined, using dual-color immunofluorescence, to be CD2+, CD3+, CD4+, CD5+, CD7-, CD8-. They do not express T-cell activation markers, and are positive for UCHL1 (CD45RO), but negative for 2H4 (CD45RA). The antigen was expressed on circulating malignant cells in Sézary syndrome (four of four cases) and adult T-cell lymphoma-leukemia (ATLL) (four of six cases) and negative in a variety of other hematologic malignancies tested. These included chronic and acute lymphoid leukemias of B and T lineage, together with chronic and acute myeloid leukemias. However, normal CH-F42+ cells do not display any of the ultrastructural features associated with Sézary or ATLL cells. The marked similarities between these conditions together with the shared expression of an otherwise very restricted surface antigen (CH-F42) provide strong evidence for the existence of a common normal counterpart. Preliminary characterization studies of the antigen, which is also expressed by K562 and Jurkat cells, suggest the CH-F42 antigen is an O-linked, sialated glycan on a glycoprotein. 相似文献
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Darbari D Loyevsky M Gordeuk V Kark JA Castro O Rana S Apprey V Kurantsin-Mills J 《Blood》2003,102(1):357-364
Sickle erythrocytes have increased ferritin and increased molecular iron on the inner membrane leaflet, and we postulated that cytosolic labile iron is also elevated. We used the fluorescent metallosensor, calcein, and a permeant Fe2+ chelator to estimate labile cytoslic Fe2+, and calcein plus an Fe3+ chelator to estimate total cytosolic labile iron (Fe2+ + Fe3+). We measured membrane nonheme iron by its reactivity with ferrozine. As estimated by calcein and Fe2+ chelator, the mean +/- SD labile Fe2+ concentration was significantly lower in hemoglobin (Hb) SS (n = 29) than hemoglobin AA (n = 17) erythrocytes (0.56 +/- 0.35 microM versus 1.25 +/- 0.65 microM; P <.001). In contrast, as estimated by calcein and Fe3+ chelator, total erythrocyte labile iron was similar in hemoglobin SS (n = 12) and hemoglobin AA (n = 10) participants (1.75 +/- 0.41 microM versus 2.14 +/- 0.93 microM; P =.2). Mean membrane nonheme iron levels were higher in hemoglobin SS cells than hemoglobin AA cells (0.0016 x 10-4 versus 0.0004 x 10-4 fmol/cell; P =.01), but much lower than the mean amounts of total labile iron (1.6-1.8 x 10-4 fmol/cell) or hemoglobin iron (18 000-19 000 x 10-4 fmol/cell). Both membrane iron and total labile iron were much less than the mean amount of iron potentially present in erythrocyte ferritin as calculated from results of other investigators (15 x 10-4 versus 34 x 10-4 fmol/cell in HbAA versus HbSS erythrocytes). We conclude that cytosolic labile iron is not elevated in hemoglobin SS erythrocytes and that elemental membrane iron is present in only trace amounts. 相似文献
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S S Rana U Dutta S K Sinha R Kochhar B Nagi D K Bhasin 《Tropical gastroenterology》2004,25(3):144-145
Portal hypertensive colopathy (PHC) is a recently described entity in patients with portal hypertension which can cause even life-threatening lower gastrointestinal bleeding. In contrast to variceal bleed, there is no standardized treatment for the control of bleeding from these lesions. We report a case of alcoholic cirrhosis with portal hypertension, in whom bleeding from colonic angiodysplasia-like lesions was effectively controlled by somatostatin infusion. 相似文献
106.
Loren M. Dobkin Heather Gould Rana E. Barar Michaela Ferrari Elisette I. Weiss Diana Greene Foster 《Women's health issues》2014,24(1):e115-e123
BackgroundThe Turnaway Study is designed to prospectively study the outcomes of women who sought—but did not all obtain—abortions. This design permits more accurate inferences about the health consequences of abortion for women, but requires the recruitment of a large number of women from remote health care facilities to a study a sensitive topic. This paper explores the Turnaway Study's recruitment process.MethodsFrom 2008 to 2010, the staff at 30 abortion-providing facilities recruited eligible female patients. Eight interventions were evaluated using multilevel logistic regression for their impact on eligible patients being approached, approached patients agreeing to go through informed consent by phone, and enrolled patients completing the baseline interview.FindingsAfter site visits, patients had roughly twice the odds of being approached by facility staff and twice the odds of then agreeing to go through informed consent. When all recruitment steps were considered together, the net effect of site visits was to increase the odds that eligible patients participated by nearly a factor of six. After the introduction of a patient gift card incentive, patients had over three times the odds of agreeing to go through informed consent. With each passing month, however, staff demonstrated a 9% reduced odds of approaching eligible patients about the study.ConclusionPrioritizing scientific rigor over the convenience of using existing datasets, the Turnaway Study confronted recruitment challenges common to medical practice-based studies and unique to sensitive services. Visiting sites and communicating frequently with facility staff, as well as offering incentives to patients to hear more about the study before informed consent, may help to increase participation in prospective health studies and facilitate evaluation of sensitive women's health services. 相似文献
107.
Sophia A. Hussen Danielle Gilliard Cleopatra H. Caldwell Karen Andes Rana Chakraborty David J. Malebranche 《Journal of urban health》2014,91(4):776-792
Young black men who have sex with men (YBMSM) are experiencing high and rising rates of HIV infection, more than any other age-risk group category in the USA. Contributors to HIV risk in this group remain incompletely elucidated. We conducted exploratory qualitative interviews with 20 HIV-positive YBMSM aged 17–24 and found that father–son relationships were perceived to be important sociocontextual influences in participants’ lives. Participants discussed the degree of their fathers’ involvement in their lives, emotional qualities of the father–son relationship, communication about sex, and masculine socialization. Participants also described pathways linking father–son relationships to HIV risk, which were mediated by psychological and situational risk scenarios. Our thematic analysis suggests that father–son relationships are important to the psychosocial development of YBMSM, with the potential to either exacerbate or attenuate sexual risk for HIV. Interventions designed to strengthen father–son relationships may provide a promising direction for future health promotion efforts in this population. 相似文献
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