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61.
RD Vaithilingam SH Safii NA Baharuddin LP Karen‐Ng R Saub F Ariffin H Ramli A Sharifuddin MFH Hidayat R Raman YK Chan NA Rani RA Rahim N Shahruddin SC Cheong PM Bartold RB Zain 《Oral diseases》2015,21(1):e62-e69
Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders. 相似文献
62.
Alexander M Aiken Philip C Hill Annette Fox Keith PWJ McAdam Dolly Jackson-Sillah Moses D Lugos Simon A Donkor Richard A Adegbola Roger H Brookes 《BMC infectious diseases》2006,6(1):66
Background
New tools are required to improve tuberculosis (TB) diagnosis and treatment, including enhanced ability to compare new treatment strategies. The ELISPOT assay uses Mycobacterium tuberculosis-specific antigens to produce a precise quantitative readout of the immune response to pathogen. We hypothesized that TB patients in The Gambia would have reduced ELISPOT counts after successful treatment. 相似文献63.
64.
Roca A Bottomley C Hill PC Bojang A Egere U Antonio M Darboe O Greenwood BM Adegbola RA 《Clinical infectious diseases》2012,55(6):816-824
Background.?This study evaluated the impact of age and pneumococcal vaccination on the density of pneumococcal nasopharyngeal carriage. Methods.?A cluster-randomized trial was conducted in rural Gambia. In 11 villages (the vaccine group), all residents received 7-valent pneumococcal conjugate vaccine (PCV-7), while in another 10 villages (the control group), only children <30 months old or born during the study period received PCV-7. Cross-sectional surveys (CSSs) were conducted to collect nasopharyngeal swabs before vaccination (baseline CSS) and 4, 12, and 22 months after vaccination. Pneumococcal density was defined using a semiquantitative classification (range, 1-4) among colonized individuals. An age-trend analysis of density was conducted using data from the baseline CSS. Mean pneumococcal density was compared in CSSs conducted before and after vaccination. Results.?Mean bacterial density among colonized individuals in the baseline CSS was 2.57 for vaccine-type (VT) and non-vaccine-type (NVT) pneumococci; it decreased with age (P?.001 for VT and NVT). There was a decrease in the density of VT carriage following vaccination in individuals older than 5 years (from 2.44 to 1.88; P?=?.001) and in younger individuals (from 2.57 to 2.11; P?=?.070) in the vaccinated villages. Similar decreases in density were observed with NVT within vaccinated and control villages. No significant differences were found between vaccinated and control villages in the postvaccination comparisons for either VT or NVT. Conclusions.?A high density of carriage among young subjects might partly explain why children are more efficient than adults in pneumococcal transmission. PCV-7 vaccination lowered the density of VT and of NVT pneumococcal carriage in the before-after vaccination analysis. Clinical Trials Registration.?ISRCTN51695599. 相似文献
65.
Gbemisola Eniola Osanyin Omololu Adegbola 《The journal of maternal-fetal & neonatal medicine》2016,29(21):3506-3510
Objective: This study was done to assess the relationship between maternal serum IL-6 levels and fetomaternal outcome following PPROM.Methodology: This was a prospective cohort study comprising 45 cases of PPROM and 45 controls of similar age, parity, and gestational age. Five milliliters of maternal serum was collected after obtaining informed consent. They were followed up till delivery and records of the delivery and neonatal outcomes were obtained. Serum IL-6 levels were determined by standard enzyme-linked immunosorbent assay [ELISA]. PPROM patients were categorized into two groups using a threshold of 14?pg/ml. Chi-square (χ2) test was used to compare categorical outcomes. p values of?<?0.05 were taken as significant.Results: The mean serum IL-6 level for the women with PPROM was (20.2?±?11.0?pg/ml), which was significantly greater than for the control subjects (13.9?±?5.8?pg/ml, p?<?0.001). Fetomaternal outcomes were all worse in those with IL-6?≥?14?pg/ml. Nevertheless, only the difference in early neonatal deaths was statistically significant.Conclusion: Measurement of maternal serum IL-6 can help to indicate hostile intrauterine environments to the fetus as well as identify patients who may benefit from pregnancy prolongation or intervention. 相似文献
66.
Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q). 相似文献
67.
A five-drug remission induction regimen with intensive consolidation for adults with acute lymphoblastic leukemia: cancer and leukemia group B study 8811 总被引:23,自引:13,他引:23
Larson RA; Dodge RK; Burns CP; Lee EJ; Stone RM; Schulman P; Duggan D; Davey FR; Sobol RE; Frankel SR 《Blood》1995,85(8):2025-2037
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL. 相似文献
68.
Dvorak AM; Tepper RI; Weller PF; Morgan ES; Estrella P; Monahan-Earley RA; Galli SJ 《Blood》1994,83(12):3600-3612
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo. 相似文献
69.
70.