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101.
Assessing the delivery of neutrophils to tissues in neutropenia 总被引:2,自引:2,他引:2
Studies of neutrophil kinetics in neutropenic individuals, as well as clinical observations of variability in the occurrence of infection among patients with neutropenia, have suggested that blood neutrophil counts may not uniformly reflect the effective delivery of neutrophils to extravascular tissues where the cells perform their principal host defense functions. To evaluate this possibility we developed a sensitive, reproducible method of measuring the extravascular delivery of neutrophils to a normal mucosal site of neutrophil turnover. This method is based upon the quantification of neutrophils recoverable from saline mouth wash specimens. Twenty-five mL specimens, obtained in a controlled manner from neutropenic patients and normal subjects, were centrifuged and the sediments resuspended in 1.0 mL Hank's buffer with 2 micrograms acridine orange, incubated at 37 degrees C for 15 minutes, and then examined in a hemocytometer chamber by fluorescence microscopy. Neutrophils could be clearly distinguished by their characteristic fluorescence and were counted. With this method as few as 1,500 neutrophils were detected reliably in mouth wash specimens. Mucosal neutrophil counts varied less than 10% with repeated sampling of individual subjects over 5-day periods and were consistently greater than 1.3 X 10(5)/specimen in non-neutropenic individuals. Although profound neutropenia was generally reflected by lower than normal oral mucosal neutrophil counts, these counts were significantly higher in individuals with chronic severe neutropenia (blood neutrophils less than 300/mm3) than in patients with acute neutropenia of comparable severity that had developed following chemotherapy. Also, in individuals recovering from profound neutropenia, neutrophils usually reappeared earlier in mouth wash specimens than in blood, and oral mucosal neutrophil counts attained recovery levels more rapidly than did blood counts. This phenomenon was particularly evident in an individual with cyclic neutropenia. Moreover, mucosal neutrophils could occasionally be detected in profoundly neutropenic patients when neutrophils were not present in blood samples. These findings indicate that mucosal neutrophil counts in individuals with neutropenia provide information about the delivery of neutrophils to tissues that may not be apparent from blood neutrophil counts alone. 相似文献
102.
Deciphering principles of morphogenesis from temporal and spatial patterns on the integument
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Ang Li Yung‐Chih Lai Seth Figueroa Tian Yang Randall B. Widelitz Krzysztof Kobielak Qing Nie Cheng Ming Chuong 《Developmental dynamics》2015,244(8):905-920
Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
103.
T H Jones C D Figueroa C Smith D R Cullen K D Bhoola 《The Journal of endocrinology》1990,124(2):327-331
Immunoreactive tissue kallikrein was co-localized with prolactin in all the eleven prolactin-secreting adenomas of the human anterior pituitary gland examined in this study. The intracellular distribution of immunoreactivity in the prolactin-secreting cells suggests that tissue kallikrein is located within the Golgi complex of these cells. Both the intracellular hormone-processing action and the kininogenase activity of tissue kallikrein may be of functional importance in human prolactinomas. 相似文献
104.
Queiro R Torre JC Belzunegui J González C De Dios JR Unanue F Figueroa M 《Seminars in arthritis and rheumatism》2002,31(4):264-270
OBJECTIVES: To analyze the clinical features of uveitis in psoriatic arthritis (PsA) and to investigate the factors predicting its appearance. PATIENTS AND METHODS: Retrospective cohort study (1991-2000) of 71 patients diagnosed with PsA according to the criteria of Moll and Wright. All patients were studied according to a standard protocol. The group was divided into 3 articular categories: axial, oligoarticular, and polyarticular. Human leukocyte antigen (HLA)-Cw typing was performed by the polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) method in 65 patients and in 177 healthy donors. HLA-DR typing was done by serologic methods in the 71 patients and in 82 healthy donors from the same racial and geographic origin. The HLA-B27 allele also was tested among the study population. All subjects with possible inflammatory ocular disease received a complete ophthalmologic examination at the Ophthalmology Department of our hospital. Only patients with uveitis were analyzed. Univariate and multivariate analyses were applied. RESULTS: Thirteen patients had uveitis (18% of this series), 4 (31%) had an insidious onset, and the remaining had acute-onset uveitis. Five cases (39%) had bilateral-simultaneous uveitis. Ten (77%) presented with anterior uveitis only, 2 with anterior and posterior pole involvement, and only 1 case with isolated posterior pole involvement. Four patients needed oral corticosteroids; 2 of them also used immunosuppresive drugs. None of our patients developed sequelae or complications. In univariate analysis, uveitis was associated with inflammatory back pain (P =.02), sacroiliac pain (P =.001), syndesmophytes (P =.001), bilateral sacroileitis (P =.0001), HLA-DR13 (P =.002), and HLA-B27 (P =.026). In multivariate analysis, the predictive factors for uveitis were bilateral sacroileitis (OR 17, 95% CI: 3.7-76, P =.0002), HLA-DR13 (OR 24, 95% CI: 3.78-150, P =.0056), and syndesmophytes (OR 9.7, 95% CI: 0.97-97, P =.05). CONCLUSIONS: Insidious onset, bilaterality, posterior pole involvement, and chronicity are common in PsA patients with uveitis. In this study, extensive axial involvement (bilateral sacroileitis and syndesmophytes), and the HLA-DR13 antigen were the best predictors for the appearance of uveitis. 相似文献
105.
Dr. J. Belzunegui C. Gonzalez L. Lopez I. Plazaola O. Maiz M. Figueroa 《Clinical rheumatology》1997,16(5):450-453
Summary Between 1988 and 1995, 1832 HIV positive patients were evaluated in our institution. We studied the epidemiologic, immunologic and bacteriologic data, laboratory tests, and X-Ray films in those with musculoskeletal infection. We reviewed twenty-one cases of musculoskeletal infection in twenty patients aged 23–35 years (mean 28,6 years, M:F=15:5). In all of them risk factor for HIV was intravenous drug abuse. The number of CD4 positive lymphocytes ranged from 0,003 to 0,5 109/l. Staphylococcus aureus was the organism responsible of the infection in twelve cases, all active intravenous drug abusers at the time the diagnosis was done. The remaining causative agents were: Mycobacterium tuberculosis (3 cases), Candida albicans (2 cases), Salmonella subgroup 1 (1 case), Neisseria gonorrhoeae (1 case), Pseudomona aeruginosa (1 case) and Streptococcus agalactiae (1 case). Fifteen infections were diagnosed between 1988 and 1991 and 6 between 1992 and 1995. Musculoskeletal infectious lesions in HIV positive patients in our country are related in the majority of cases to intravenous drug abuse. In the last four years due to a National medical health care plan conducted to educate this group of people the number of musculoskeletal infections is decreasing. 相似文献
106.
R D Robinson E L Murphy R J Wilks F A Neva S I Terry B Hanchard J P Figueroa W A Blattner 《The Journal of tropical medicine and hygiene》1991,94(6):411-415
A subsample (1.6%; n = 13,260) of a healthy Jamaican population of food-handlers, studied by Murphy et al. (1991), who were serologically positive (n = 99) or negative (n = 113) for HTLV-I was investigated for intestinal parasitic infection using coprological methods. Helminth infection included Ascaris lumbricoides (2.8%), Trichuris trichiura (7.1%) and hookworms (6.1%). Entamoeba coli was found in 21.8% of samples, while E. hartmanni, Giardia lamblia, Endolimax nana, Iodamoeba bütschlii and Chilomastix mesnili each occurred in less than 10% of responders. T. trichiura displayed a higher prevalence (10.6 vs 3%) (chi 2 = 4.623; P = 0.03) in the HTLV-I negative group. G. lamblia was detected more frequently among HTLV-I carriers compared to controls (9.1 and 3.5%, respectively), but the association was not statistically significant (chi 2 = 2.825; P = 0.09). Infection with intestinal parasites is likely to occur independent of HTLV-I status: however, possible HTLV-I-induced immunosuppression may lead to higher intensity infections of certain organisms thus facilitating easier detection using parasitological methods. The immunomodulatory potential of HTLV-I infection in the aetiology of non-malignant diseases requires further investigation. 相似文献
107.
James Reigle Dina Secic Jacek Biesiada Collin Wetzel Behrouz Shamsaei Johnson Chu Yuanwei Zang Xiang Zhang Nicholas J. Talbot Megan E. Bischoff Yongzhen Zhang Charuhas V. Thakar Krishnanath Gaitonde Abhinav Sidana Hai Bui John T. Cunningham Qing Zhang Laura S. Schmidt W. Marston Linehan Mario Medvedovic David R. Plas Julio A. Landero Figueroa Jarek Meller Maria F. Czyzyk-Krzeska 《The Journal of clinical investigation》2021,131(1)
108.
109.
Amplification of genes encoding human myeloid membrane antigens after DNA-mediated gene transfer 总被引:2,自引:0,他引:2
Spontaneous amplification of genes encoding two different human myeloid surface antigens was observed after DNA-mediated gene transfer of cellular DNA from the human myeloid cell line HL-60 into NIH-3T3 mouse fibroblasts. Transformed recipient cells with highly amplified expression of either of two donor membrane polypeptides, gp150 or p67, were isolated with a fluorescence-activated cell sorter (FACS), using monoclonal antibodies specific for human myeloid cells. Immunoprecipitation of enzymatically radioiodinated polypeptides from the surface of transformed NIH-3T3 cells confirmed that expression of these proteins was amplified tenfold to 20-fold in comparison to their expression on human myeloid cell lines. The cellular DNA of cloned secondary and tertiary transformants expressing high levels of gp150 and p67 contained amplified sets of DNA restriction fragments that hybridized with human repetitive DNA sequences. Cytogenetic analysis of subclones overexpressing gp150 revealed extrachromosomal double minutes (DMs), whose presence correlated with the unstable expression of the membrane polypeptide. Human sequences in gp150-positive clones did not localize to chromosomes, consistent with their association with extrachromosomal DMs. By contrast, p67-positive subclones stably expressed the antigen, and in situ hybridization to metaphase spreads demonstrated that amplified human DNA sequences were integrated into a specific marker chromosome. Cytogenetic analysis of the parental NIH- 3T3 subclone used in these studies disclosed DMs in a low percentage of metaphases, suggesting that the recipient cells have a propensity for amplifying donor DNA. 相似文献
110.
Molecular heterogeneity in acute leukemia lineage switch 总被引:1,自引:0,他引:1
Gagnon GA; Childs CC; LeMaistre A; Keating M; Cork A; Trujillo JM; Nellis K; Freireich E; Stass SA 《Blood》1989,74(6):2088-2095
Six cases of acute leukemia that underwent lineage switch from acute lymphocytic leukemia to acute myelogenous leukemia are reported. The mean age of the patients was 24 years, time to conversion was 36 months, and survival after conversion was only 3 months. Of the three cases which showed abnormal metaphases at both diagnosis and conversion, two (cases 2, 5) showed related cytogenetic abnormalities, and the third showed (case 3) independent chromosomal changes. Molecular analysis for immunoglobulin heavy chain and T-cell receptor beta chain genes showed that five of the six cases had rearrangement of at least one of these lymphoid associated genes at conversion to acute myelogenous leukemia. The single case (case 3) in which there were no lymphoid gene rearrangements at conversion was also the only case in which independent karyotypic abnormalities at diagnosis and conversion were demonstrated. Our findings suggest that lineage switch can represent either relapse of the original clone with heterogeneity at the molecular level or the emergence of a second new leukemic clone without molecular heterogeneity. 相似文献