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291.
Mapping Bone Changes at the Proximal Femoral Cortex of Postmenopausal Women in Response to Alendronate and Teriparatide Alone,Combined or Sequentially 下载免费PDF全文
Tristan Whitmarsh Graham M Treece Andrew H Gee Kenneth ES Poole 《Journal of bone and mineral research》2015,30(7):1309-1318
Combining antiresorptive and anabolic drugs for osteoporosis may be a useful strategy to prevent hip fractures. Previous studies comparing the effects of alendronate (ALN) and teriparatide (TPTD) alone, combined or sequentially using quantitative computed tomography (QCT) in postmenopausal women have not distinguished cortical bone mineral density (CBMD) from cortical thickness (CTh) effects, nor assessed the distribution and extent of more localized changes. In this study a validated bone mapping technique was used to examine the cortical and endocortical trabecular changes in the proximal femur resulting from an 18‐month course of ALN or TPTD. Using QCT data from a different clinical trial, the global and localized changes seen following a switch to TPTD after an 18‐month ALN treatment or adding TPTD to the ALN treatment were compared. Ct.Th increased (4.8%, p < 0.01) and CBMD decreased (?4.5%, p < 0.01) in the TPTD group compared to no significant change in the ALN group. A large Ct.Th increase could be seen for the switch group (2.8%, p < 0.01) compared to a significantly smaller increase for the add group (1.5%, p < 0.01). CBMD decreased significantly for the switch group (–3.9%, p < 0.01) and was significantly different from no significant change in the add group. Ct.Th increases were shown to be significantly greater for the switch group compared to the add group at the load bearing regions. This study provides new insights into the effects of ALN and TPTD combination therapies on the cortex of the proximal femur and supports the hypothesis of an increased bone remodeling by TPTD being mitigated by ALN. © 2014 American Society for Bone and Mineral Research. 相似文献
292.
Whang-Peng J; Knutsen T; Jaffe ES; Steinberg SM; Raffeld M; Zhao WP; Duffey P; Condron K; Yano T; Longo DL 《Blood》1995,85(1):203-216
Few reports correlating specific cytogenetic abnormalities with distinct subtypes of lymphoma have performed serial studies at diagnosis and at tumor recurrence or progression. In our file of 325 cytogenetically analyzed non-Hodgkin's lymphoma (NHL) patients studied over the past decade, 43 had serial biopsies, 39 of whom had at least two successful preparations; of the 43, nine had one and 32 had two or more cytogenetically abnormal specimens. In this study, we correlated cytogenetic, histopathologic, molecular, and clinical parameters. Patients with low-grade lymphomas were as likely as patients with intermediate- or high-grade lymphomas to acquire new chromosomal abnormalities with time (16 of 23 patients as compared with 7 of 16; P2 = .11, chi 2 test). In four patients, originally diagnosed indolent disease progressed to aggressive disease; all had t(14;18), all gained additional chromosomal abnormalities with disease progression, and three of the four expressed abnormalities associated with disease progression and/or short survival: der(18), +7, and/or +12. Cytogenetic results from early disease were compared with those obtained later in disease: in the t(14;18) group, the most common abnormalities were +7 (eight patients) and der(18) (five patients), both seen later in disease. The most common abnormalities in patients without t(14;18) were 6q deletions; they were seen in both early and late disease and were associated with significantly shorter survivals (P2 = .0014) compared with all patients without 6q deletions. Secondary chromosomal abnormalities, observed after at least one previous abnormal study, were seen in 19 of 22 t(14;18) patients and in 11 of 21 patients without t(14;18) and were associated with a poor survival (P2 = .13) compared with patients without any secondary chromosomal abnormalities. Chromosome 1 abnormalities were seen in almost half of the patients and were observed in initial specimens and early in disease as well as late in disease and as secondary abnormalities; 1q involvement was more frequent than 1p (15 versus eight patients) and was significantly associated with poor survival only in patients with intermediate-/high- grade disease; the most common breakpoints were 1q21-q22 (nine patients) and 1p36 (six patients). Breakpoints at 2q21 and 3q27-q29 were limited to patients with t(14;18) and were almost exclusively secondary in nature. Molecular studies in 24 of our patients showed discrepancies with the cytogenetic results in only three patients: two had t(14;18) but no molecular rearrangements while two patients had no visible t(14;18) but were positive for major breakpoint region (MBR) rearrangement. The presence of MBR or minor breakpoint cluster (MCR) rearrangement had no apparent effect on survival.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
293.
The value of complement and immune complex determinations in monitoring disease activity in patients with systemic lupus erythematosus 总被引:21,自引:0,他引:21
R M Valentijn H van Overhagen H M Hazevoet J Hermans A Cats M R Daha L A van ES 《Arthritis and rheumatism》1985,28(8):904-913
Serial serum samples from 33 patients with systemic lupus erythematosus were tested for CH50, C3, C4, and circulating immune complexes. Circulating immune complexes were determined by 5 different assays. Disease activity was determined by a scoring system we devised. On an interpatient analysis, overall disease activity correlated significantly with levels of CH50, C3, and a positive result on C1q binding assay. However, with the exception of depressed C3 levels, the sensitivity, specificity, and predictive values of all the serologic tests were low. An intrapatient analysis revealed a patient-specific activity parameter in 11 of the 33 patients. We conclude that these serologic tests are not reliable in assessing disease activity in patients with systemic lupus erythematosus, although a small subgroup of patients will exhibit a patient-specific activity parameter. 相似文献
294.
Sylvia Brugman Kerstin Schneeberger Merlijn Witte Mark R Klein Bartholomeus van den Bogert Jos Boekhorst Harro M Timmerman Marianne L Boes Michiel Kleerebezem Edward ES Nieuwenhuis 《Gut microbes》2014,5(6):737-747
Dysbiosis of the intestinal microbial community is considered a risk factor for development of chronic intestinal inflammation as well as other diseases such as diabetes, obesity and even cancer. Study of the innate and adaptive immune pathways controlling bacterial colonization has however proven difficult in rodents, considering the extensive cross-talk between bacteria and innate and adaptive immunity. Here, we used the zebrafish to study innate and adaptive immune processes controlling the microbial community. Zebrafish lack a functional adaptive immune system in the first weeks of life, enabling study of the innate immune system in the absence of adaptive immunity. We show that in wild type zebrafish, the initial lack of adaptive immunity associates with overgrowth of Vibrio species (a group encompassing fish and human pathogens), which is overcome upon adaptive immune development. In Rag1-deficient zebrafish (lacking adaptive immunity) Vibrio abundance remains high, suggesting that adaptive immune processes indeed control Vibrio species. Using cell transfer experiments, we confirm that adoptive transfer of T lymphocytes, but not B lymphocytes into Rag1-deficient recipients suppresses outgrowth of Vibrio. In addition, ex vivo exposure of intestinal T lymphocytes to Rag1-deficient microbiota results in increased interferon-gamma expression by these T lymphocytes, compared to exposure to wild type microbiota. In conclusion, we show that T lymphocytes control microbial composition by effectively suppressing the outgrowth of Vibrio species in the zebrafish intestine. 相似文献
295.
Heterologous expression of rat P450 2E1 in a mammalian cell line: in situ metabolism and cytotoxicity of N-nitrosodimethylamine 总被引:1,自引:0,他引:1
GM0637, a human fibroblast cell line, was transfected with pCMV2E1, an
expression vector containing the full length cDNA for rat cytochrome P450
2E1 (P450 2E1), and with pCMVneo, which contained vector alone, and the
selected clones were designated GM2E1 and GMneo, respectively. Western blot
analysis showed that GM2E1, but not GMneo, expressed a protein that reacted
with anti-human P450 2E1 antibody. The 7- ethoxycoumarin
O-deethylase,p-nitrophenol hydroxylase, and N- nitrosodimethylamine (NDMA)
demethylase activities of the P450 in these cells were measured in
monolayer cell cultures without preparing microsomes. Exposure of the GM2E1
cells to NDMA for 4 days caused severe decreases in cell viability, as
determined by crystal violet uptake, and showed a sigmoidal dose-response
curve with a median lethal dose of 17 microM. In contrast, the viability of
GMneo cells was not altered by NDMA even at concentrations up to 10 mM.
Time- and concentration-dependent methylation of DNA, RNA and protein by
[14C]NDMA was only observed in cells expressing P450 2E1. Inhibitors of
P450 2E1 activity such as ethanol, 4-methylpyrazole, and isoniazid caused a
90% decrease in the methylation of cellular macromolecules and also
completely protected the cells against NDMA-mediated toxicity. The
cytotoxicity due to exposure to NDMA was partially inhibited by
antioxidants such as N-acetylcysteine, ascorbic acid, butylated
hydroxyanisole and N-t-butyl-alpha-phenylnitrone but was not potentiated
upon glutathione depletion. These results document the ability of rat P450
2E1 to metabolize NDMA to toxic reactive intermediates and demonstrate that
this cell line provides a useful model for studying the mechanisms of
metabolism-mediated toxicity and carcinogenesis.
相似文献
296.
DP Strachan HR Anderson ES Limb A O'Neill N Wells 《Archives of disease in childhood》1994,70(3):174-178
Parents of 5472 children aged 5-17 years from 3209 families were interviewed in a nationwide household survey. In the past year, 15.0% of children had wheezed, 2.2% had more than 12 attacks, and 2.3% had experienced a speech limiting attack. Altogether 4.3% were woken more than once a week by wheezing, 13.1% had doctor diagnosed asthma, and 13.6% had been prescribed antiasthmatic drugs in the past year. With increasing age, morbidity related to wheezing declined to a greater extent than annual period prevalence. The prevalence of wheeze varied little by socioeconomic group, but there were marked trends in all three indices of severity towards increased morbidity in poorer families. Diagnostic labelling and drug treatment of wheezy children did not differ substantially with socioeconomic status. Thus, a degree of socioeconomic equality exists in the process of medical care for childhood asthma in Britain. This does not appear to have resulted in equality of outcome. 相似文献
297.
AB Downie J Mulligan ES McCaughey RJ Stratford PR Betts LD Voss 《Archives of disease in childhood》1996,75(1):32-35
Indian childhood cirrhosis (ICC) is an almost uniformly fatal disease whose outcome may be modified with penicillamine if given at a sufficiently early stage. Twenty nine children with ICC seen in Pune, India, in 1980-7, who had survived at least five years from onset of penicillamine treatment, were reviewed aged 6.3 to 13 years. They were assessed clinically, biochemically, histologically, and by duplex Doppler ultrasound examination. None had symptoms suggestive of liver disease. There were no toxic effects of penicillamine other than asymptomatic proteinuria. Hepatosplenomegaly reduced significantly and liver function tests returned to normal in all. In four children, significant hepatosplenomegaly was associated with an abnormal duplex Doppler hepatic vein flow pattern and micronodular cirrhosis on biopsy. Clinical findings, growth and development, and ultrasound examination were normal in the remainder. Review of serial liver biopsy specimens showed a sequence of recovery from ICC through inactive micronodular cirrhosis to virtually normal histological appearances. The four children who still have micronodular cirrhosis beyond four years from onset remain on penicillamine treatment. In the others penicillamine was stopped after 1-7 (mean 3.5) years without relapse, strong evidence that ICC is not due to an inborn error of copper metabolism. 相似文献
298.
L Mankhambo A Phiri K Chiwaya J Waluza ES Borgstein SM Graham 《Malawi medical journal : the journal of Medical Association of Malawi》2007,19(3):122-125
We report three cases of brain abscess in children admitted to QECH in 2006. All children were HIV-uninfected. One case was associated with staphylococcal empyema, another with chronic suppurative otitis media and mastoiditis, and the third case had no identified extracranial focus of infection. These cases illustrate the difficulties of diagnosis and management of brain abscesses in the resource-poor setting where other causes of infection of the central nervous system are common. The typical clinical presentation of brain abscess of altered mental state and seizures is also characteristic of cerebral malaria and meningitis and it is likely that many cases of brain abscess in Malawian children are not diagnosed. The value of cranial CT scan, ideally with contrast, for diagnosis and management of brain abscess is highlighted by these cases. 相似文献
299.
M. I. KOOLEN M. R. DAHA M. FRÖLICH L. A. VAN ES P. VAN BRUMMELEN 《European journal of clinical investigation》1984,14(3):171-174
The relevance of age and activity of the renin-angiotensin-aldosterone system to the excretion of urinary kallikrein (Ukal) was studied in twenty-five patients with essential hypertension and forty normotensive controls. The age range for both study groups was 20-60 years. Ukal was measured by radioimmunoassay and by an amidolytic assay. Results of both assays correlated closely (r = 0.93, n = 65, P less than 0.001). For all hypertensives Ukal excretion was not significantly different from that of controls. However, older hypertensives (greater than 40 years, n = 13) had a significantly lower Ukal excretion than normotensives of the same age (n = 20) (radioimmunoassay 67.2 (SEM 7.2) v. 105.1 (SEM 8.4) micrograms (24 h)-1; and amidolytic method 0.84 (SEM 0.10) v. 1.13 (SEM 0.08) U (24 h)-1). No correlation was found between Ukal excretion and plasma renin or aldosterone. In fact, the aldosterone level was highest in older hypertensives. In conclusion, the lower Ukal excretion in hypertensives over 40 is likely to be secondary to the long-standing high blood pressure. Under basal conditions, Ukal excretion seems little influenced by the activity of the renin-angiotensin-aldosterone system. 相似文献
300.
ES Perry ; RH Moore ; TA Berger ; LC Billups ; DA Maybee ; KF Salata ; LE Lippert 《Transfusion》1996,36(4):318-321
BACKGROUND: Reticulocytes are important in the phenotyping of transfused patients. Reticulocytes can persist in blood units for the shelf life of the unit. STUDY DESIGN AND METHODS: Temperature dependence of reticulocyte persistence was examined in vitro at 4, 24, and 37 degrees C by using thiazole orange staining and flow cytometric analysis. Two-color flow cytometric analysis was used to evaluate the persistence of donor reticulocytes in transfused patients. RESULTS: Flow cytometric analysis using thiazole orange demonstrated that persistence of reticulocytes in units of stored CPDA-1 blood was temperature-dependent. Reticulocytes disappeared over 13 and 6 days at 24 degrees C and 37 degrees C, respectively, but at 4 degrees C the reticulocyte count changed little over 35 days. Two-color flow cytometric analysis of reticulocyte antigens was used to follow donor reticulocytes in 14 transfusion events in nine different patients. Donor reticulocytes persisted through 24 hours in 75 percent of the patients and were detectable at 48 hours in three patients. CONCLUSION: This study demonstrates that reticulocytes persist during refrigerated storage; they are detectable in the circulation of most recipients for the first 24 hours after transfusion and in the circulation of a few recipients after 48 hours. These findings may have relevance for separation techniques based on reticulocyte density in samples drawn shortly after transfusion and for evaluation of reticulocyte counts in patients with hematologic abnormalities. 相似文献