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Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
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BACKGROUND: Quality of life has increased in popularity as an outcome measure in health research. However, the measurement of quality of life has been questioned on methodologic grounds, as it often shows little association with objective measures of disease status. OBJECTIVE: For this report we studied the determinants of pediatric asthma caregiver report of quality of life and its relationship to disease burden. METHOD: Ninety-eight children who were admitted to a Pediatric Day Program for an asthma evaluation were enrolled in an outcome study. A complete set of medical records for the 2-year period before and after the admission was collected and systematically coded for health care utilization. Using the Pediatric Asthma Caregiver's Quality of Life Questionnaire, data were collected at baseline, discharge, and year after the admission. Caregiver negative affect (anxiety and depression), measured with the Brief Symptom Inventory, was also collected at baseline and discharge. RESULTS: Caregiver report of quality of life was unrelated to health care utilization at baseline but instead was significantly related to baseline caregiver negative affect. A significant relationship between health care utilization and quality of life was present at followup. The Emotional Function scale from the quality of life measure can account for most of the relationship between quality of life and negative affect. CONCLUSIONS: Caregiver affect may have a considerable influence on report of quality of life. Understanding the individual characteristics of the respondent is important when using a quality of life instrument as an outcome measure.  相似文献   
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A total of five Wolf-Hirschhorn syndrome (WHS) patient with a 4p16.3 de novo microdeletion was referred because of genotype-phenotype inconsistencies, first explained as phenotypic variability of the WHS. The actual deletion size was found to be about 12 Mb in three patients, 5 Mb in another one and 20 Mb in the last one, leading us to hypothesize the presence of an extrachromosome segment on the deleted 4p. A der(4)(4qter --> p16.1::8p23 --> pter) chromosome, resulting from an unbalanced de novo translocation was, in fact, detected in four patients and a der(4)(4qter --> q32::4p15.3 --> qter) in the last. Unbalanced t(4;8) translocations were maternal in origin, the rec(4p;4q) was paternal. With the purpose of verifying frequency and specificity of this phenomenon, we investigated yet another group of 20 WHS patients with de novo large deletions (n = 13) or microdeletions (n = 7) and with apparently straightforward genotype-phenotype correlations. The rearrangement was paternal in origin, and occurred as a single anomaly in 19 out of 20 patients. In the remaining patient, the deleted chromosome 4 was maternally derived and consisted of a der(4)(4qter --> 4p16.3::8p23 --> 8pter). In conclusions, we observed that 20% (5/25) of de novo WHS-associated rearrangements were maternal in origin and 80% (20/25) were paternal. All the maternally derived rearrangements were de novo unbalanced t(4;8) translocations and showed specific clinical phenotypes. Paternally derived rearrangements were usually isolated deletions. It can be inferred that a double, cryptic chromosome imbalance is an important factor for phenotypic variability in WHS. It acts either by masking the actual deletion size or by doubling a quantitative change of the genome.  相似文献   
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The co-segregation in one pedigree of bipolar affective disorder with Darier's disease whose gene is on chromosome 12q23-q24.1, and findings from linkage and association studies with the neighbouring gene of phospholipase A2 (PLA2) indicate that PLA2 may be considered as a candidate gene for affective disorders. All relevant genetic association studies, however, were conducted on bipolar patients. In the present study, the possible association between the PLA2 gene and unipolar affective disorder was examined on 321 unipolar patients and 604 controls (all personally interviewed), recruited from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, and Italy) participating in the European Collaborative Project on Affective Disorders. After controlling for population group and gender, one of the eight alleles of the investigated marker (allele 7) was found to be more frequent among unipolar patients with more than three major depressive episodes than among controls (P<0.01); genotypic association was also observed, under the dominant model of genetic transmission (P<0.02). In addition, presence of allele 7 was correlated with a higher frequency of depressive episodes (P<0.02). These findings suggest that structural variations at the PLA2 gene or the chromosomal region around it may confer susceptibility for unipolar affective disorder.  相似文献   
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Folate receptor family members (FOLRs) mediate the delivery of 5-methyltetrahydrofolate to the interior of, out of within, or between cells in a process known as potocytosis. Three FOLRs and a pseudogene map to 11q13.4. The aim of this study was to verify whether FOLRs could be responsible for the onset of nonsyndromic cleft lip with or without cleft palate (CL/P). Linkage and linkage disequilibrium between genetic markers and disorder were analyzed. Patients and their mothers from 71 familial CL/P pedigrees and 75 sporadic cases from Italian population were investigated by PCR-SSCP analysis. Data from mutation scanning allowed us to find only a silent mutation in FOLR1 present in a mother and her child. Our findings do not support FOLR1 and FOLR2 genes in the onset of CL/P.  相似文献   
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Mice responded to lipopolysaccharide (LPS) with a dose-dependent, monophasic hypothermia reaching a maximum at 2 h postinjection. Degraded polysaccharide was not active; free lipid A, however, induced a similar pattern of hypothermia, indicating that the hypothermic principle of LPS was embedded within the lipid A component. The hypothermic response of mice to LPS was modified by prior exposure of the host to LPS. This altered reactivity was manifested by refractory periods (early and late tolerance), in which animals no longer responded with hypothermia, or a hyperreactive phase (hypersensitivity), in which hypothermic responses were greatly augmented upon LPS challenge. Thus, tolerance observed 24 h after a single injection of LPS (early tolerance) was followed, on further LPS challenge, by an enhanced hypothermic responses reaching a maximum on day 4. Further daily exposure of the animals to LPS eliminated hyperreactivity and led to the establishment of a late tolerance maximally expressed on day 8. Hyperreactivity could also be evoked on day 4 after a single injection of LPS. Mice pretreated with Salmonella S- and R-form LPS or free lipid A (Salmonella) demonstrated tolerance and hyperreactivity to both homologous and heterologous challenge. In addition, complete cross-tolerance was observed with S-form LPS derived from Shigella. It was concluded that the differential effects of LPS on host responses (tolerance and hyperreactivity) were due to lipid A.  相似文献   
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The effect of two synthetic lipid A partial structures, compound 406 (or LA-14-PP, identical in structure to the lipid A precursor, known as Ia or IVa) and compound 401 (lipid X), on the in vitro modulation of endotoxin (lipopolysaccharide)-induced interleukin-6 production by human blood mononuclear cells was investigated. Lipopolysaccharide of Salmonella abortus equi and synthetic Escherichia coli-type lipid A (compound 506, or LA-15-PP) had potent interleukin-6-inducing capacities. The maximum release of interleukin-6 was found after stimulation with 1 to 10 ng of lipopolysaccharide or 10 to 100 ng of synthetic E. coli-type lipid A per ml. Both synthetic lipid A partial structures (compounds 406 and 401) failed to induce interleukin-6 release. However, they inhibited lipopolysaccharide- or lipid A-induced interleukin-6 production in a dose-dependent manner. Inhibition was found not only in mononuclear cells but also in purified monocytes and was not due to a shift in the kinetics of cytokine production. Suppression was manifested in the early stage of interleukin-6 production. Inhibition was also found in the presence of recombinant gamma interferon, indicating that compound 406 and recombinant gamma interferon act in different, independent pathways. Our data, therefore, indicate that the inhibition of interleukin-6 production by lipid A partial structures may help elucidate the mechanism of interaction of the lipid A component of lipopolysaccharide with immune cells in the inflammatory reaction during gram-negative infection.  相似文献   
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