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31.
Short stature can be a severe side-effect of bone marrow transplantation (BMT). Because of the effect of weight changes on growth rate and on plasma insulin-like growth factor (IGF I), we analyzed changes in height and body mass index (BMI) in 53 patients given BMT. Group 1 (n = 22) was given 12 Gy total body irradiation (TBI) as six fractions, group 2 (n = 14) 10 Gy TBI (one dose), group 3 (n = 8) 6 Gy total lymphoid irradiation (one dose), and group 4 (n = 9) chemotherapy alone. At the first evaluation, 13/36 patients in groups 1 and 2 had low growth hormone (GH) peaks after stimulation. The mean plasma IGF I concentrations (z score) were similar in groups 1 (-2.9 +/- 0.3) and 2 (-2.5 +/- 0.3), and in groups 3 (-1.4 +/- 0.3) and 4 (-1.4 +/- 0.7), but those of group 1 were lower than those of groups 3 (P < 0.01) and 4 (P < 0.05), and those of group 2 than those of group 3 (P < 0.05). BMI during the 5 years after BMT did not change in groups 1 and 2, decreased in group 3, and increased in group 4. However, these changes were not significant. Most of the patients given TBI had BMI below the mean at 2 (66%) and 5 (57%) years later. Their BMI and leptin concentrations correlated positively with each other (P = 0.005), and negatively with GH peak (P = 0.02 for BMI and 0.007 for leptin). In conclusion, this study suggests that TBI actually decreases GH secretion and is followed by a persistent low BMI. The negative relationship between GH peak and leptin may indicate that both are markers of a TBI-induced hypothalamic-pituitary lesion.  相似文献   
32.
AimsThe complement system, and especially C5a, plays an important role in the pathophysiology of renal diseases and post-transplant renal injury. The two receptors for C5a are C5a receptor (C5aR) and C5a-like-receptor-2 (C5L2). Only renal C5aR expression has been reported, although exact localization and alterations in expression after transplantation are unknown.Materials and resultsRenal C5aR and C5L2 expression and localization were analyzed immunohistochemically. C5aR and C5L2 expression was analyzed in human kidney biopsies obtained from living donors and patients suffering from acute tubular necrosis, acute cellular and vascular rejection or IF/TA.C5aR was expressed in the thick ascending limb of Henle's loop and first part of the distal convoluted tubule (DCT). Under inflammatory conditions, C5aR was de novo expressed in proximal tubuli. C5L2 was expressed in the kidney and localized to DCT1, DCT2 and connecting tubule. Persistent distal tubular expression of both receptors was demonstrated after renal transplantation.ConclusionsThis study shows distinct renal expression patterns for C5aR and C5L2. Our findings suggest a functional role for renal C5L2 rather than being a C5a decoy receptor. Future studies focusing on renal C5a–C5aR interaction should take differential C5aR and C5L2 expression into account, alongside abundant C5aR expression on infiltrating cells.  相似文献   
33.
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This study examined the associations between substance abuse problems in severely mentally ill patients, outcome and Assertive Community Treatment (ACT) model fidelity. In a prospective longitudinal study, ACT model fidelity and patient outcomes were assessed in 20 outpatient treatment teams using the Health of the Nation Outcome Scales, Camberwell Assessment of Needs short appraisal schedule and measures of service use. Five hundred and thirty severely mentally ill patients participated in the study. Substance abuse problems were assessed three times during a 2-year follow-up period. This study found that among patients with severe mental illness, patients with an addiction problem had more serious psychosocial problems at baseline. Substance abuse problems showed improvement over time, but this was not associated with ACT model fidelity. The study indicates that investment by teams to improve a patient’s psychosocial situation can lead to improvements on substance problems.  相似文献   
35.

Background and Objectives

A negative self-view is a prominent factor in most cognitive vulnerability models of depression and anxiety. Recently, there has been increased attention to differentiate between the implicit (automatic) and the explicit (reflective) processing of self-related evaluations. This longitudinal study aimed to test the association between implicit and explicit self-esteem and symptoms of adolescent depression and social anxiety disorder. Two complementary models were tested: the vulnerability model and the scarring effect model.

Method

Participants were 1641 first and second year pupils of secondary schools in the Netherlands. The Rosenberg Self-Esteem Scale, self-esteem Implicit Association Test and Revised Child Anxiety and Depression Scale were completed to measure explicit self-esteem, implicit self-esteem and symptoms of social anxiety disorder (SAD) and major depressive disorder (MDD), respectively, at baseline and two-year follow-up.

Results

Explicit self-esteem at baseline was associated with symptoms of MDD and SAD at follow-up. Symptomatology at baseline was not associated with explicit self-esteem at follow-up. Implicit self-esteem was not associated with symptoms of MDD or SAD in either direction.

Limitations

We relied on self-report measures of MDD and SAD symptomatology. Also, findings are based on a non-clinical sample.

Conclusions

Our findings support the vulnerability model, and not the scarring effect model. The implications of these findings suggest support of an explicit self-esteem intervention to prevent increases in MDD and SAD symptomatology in non-clinical adolescents.  相似文献   
36.
Unlike nonhuman primates, songbirds learn to vocalize very much like human infants acquire spoken language. In humans, Broca's area in the frontal lobe and Wernicke's area in the temporal lobe are crucially involved in speech production and perception, respectively. Songbirds have analogous brain regions that show a similar neural dissociation between vocal production and auditory perception and memory. In both humans and songbirds, there is evidence for lateralization of neural responsiveness in these brain regions. Human infants already show left-sided dominance in their brain activation when exposed to speech. Moreover, a memory-specific left-sided dominance in Wernicke's area for speech perception has been demonstrated in 2.5-mo-old babies. It is possible that auditory-vocal learning is associated with hemispheric dominance and that this association arose in songbirds and humans through convergent evolution. Therefore, we investigated whether there is similar song memory-related lateralization in the songbird brain. We exposed male zebra finches to tutor or unfamiliar song. We found left-sided dominance of neuronal activation in a Broca-like brain region (HVC, a letter-based name) of juvenile and adult zebra finch males, independent of the song stimulus presented. In addition, juvenile males showed left-sided dominance for tutor song but not for unfamiliar song in a Wernicke-like brain region (the caudomedial nidopallium). Thus, left-sided dominance in the caudomedial nidopallium was specific for the song-learning phase and was memory-related. These findings demonstrate a remarkable neural parallel between birdsong and human spoken language, and they have important consequences for our understanding of the evolution of auditory-vocal learning and its neural mechanisms.  相似文献   
37.
Turner syndrome (TS) is the result of (partial) X chromosome monosomy. In general, the diagnosis is based on karyotyping of 30 blood lymphocytes. This technique, however, does not rule out tissue mosaicism or low grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome. We investigated different approaches to improve the detection of mosaicisms in 162 adult women with TS (mean age 29.9 ± 10.3). Standard karyotyping identified 75 patients (46.3%) with a non-mosaic monosomy 45,X. Of these 75 patients, 63 underwent additional investigations including FISH on buccal cells with X- and Y-specific probes and PCR-Y on blood. FISH analysis of buccal cells revealed a mosaicism in 19 of the 63 patients (30.2%). In five patients the additional cell lines contained a (derivative) Y chromosome. With sensitive real-time PCR we confirmed the presence of this Y chromosome in blood in three of the five cases. Although Y chromosome material was established in ovarian tissue in two patients, no gonadoblastoma was found. Our results confirm the notion that TS patients with 45,X on conventional karyotyping often have tissue specific mosaicisms, some of which include a Y chromosome. Although further investigations are needed to estimate the risk of gonadoblastoma in patients with Y chromosome material in buccal cells, we conclude that FISH or real-time PCR on buccal cells should be considered in TS patients with 45,X on standard karyotyping.  相似文献   
38.

Introduction:

The optimal surgical treatment of end-stage primary glenohumeral osteoarthritis remains controversial. The objective of this article is to systematically review the current available literature to formulate evidence-based guidelines for treatment of this pathology with an arthroplasty.

Materials and Methods:

A systematic literature search was performed to identify all articles from 1990 onward that presented data concerning treatment of glenohumeral arthritis with total shoulder arthroplasty (TSA) or head arthroplasty (HA) with a minimal follow-up of 7 years. The most relevant electronic databases were searched.

Results:

After applying the inclusion and exclusion criteria, we identified 18 studies (of the initial 832 hits). The search included a total of 1,958 patients (HA: 316 and TSA: 1,642) with 2,111 shoulders (HA: 328 + TSA: 1,783). The revision rate for any reason in the HA group (13%) was higher than in the TSA group (7%) (P < 0.001). There was a trend of a higher complication rate (of any kind) in the TSA group (12%) when compared with the HA group (8%) (P = 0.065). The weighted mean improvement in anteflexion, exorotation and abduction were respectively 33°, 15° and 31° in the HA group and were respectively 56°, 21° and 48° in the TSA group. Mean decrease in pain scores was 4.2 in the HA and 5.5 in the TSA group.

Conclusion:

Finally, we conclude that TSA results in less need for revision surgery, but has a trend to result in more complications. The conclusions of this review should be interpreted with caution as only Level IV studies could be included.

Level of Evidence:

IV.  相似文献   
39.
40.
Rhabdoid tumours (RTs) are rare but highly aggressive tumours of childhood. Their rarity and their miscellaneous locations make the diagnosis particularly challenging for pathologists. Central nervous system and peripheral RTs have been associated with biallelic inactivation of the hSNF5/INI1/SMARCB1 (hSNF5/INI1) tumour suppressor gene. Immunohistochemistry (IHC) with a monoclonal anti-hSNF5/INI1 antibody has recently been proposed as an efficient diagnostic tool for RTs. We have conducted a retrospective study of 55 tumours referred to our institution with a suspicion of RT. This analysis included pathological review, IHC with anti-hSNF5/INI1 antibody, and molecular investigation using quantitative DNA fluorescent analysis and sequencing of the nine exons of hSNF5/INI1. The molecular lesion could be detected in 37 of the 39 cases exhibiting negative staining for hSNF5/INI1. In the two discrepant cases, the lack of detection of genetic abnormality was probably owing to the presence of a high number of non-tumour cells in the samples. This indicates that hSNF5/INI1 IHC is very sensitive and highly specific for the detection of hSNF5/INI1 loss-of-function. Among the 38 cases with typical RT histological features, six failed to exhibit hSNF5/INI1 mutation and stained positive for hSNF5/INI1. This strongly supports the evidence of a second genetic locus, distinct from hSNF5/INI1, associated with RT. Conversely, seven tumours with histological features poorly compatible with RT stained negative for hSNF5/INI1; they nevertheless exhibited an age of onset and a clinical behaviour similar to RT. This suggests that hSNF5/INI1 inactivation is not strictly limited to typical RT but characterizes a wider family of hSNF5/INI1-deficient tumours. Consequently, we believe that anti-hSNF5/INI1 IHC should be performed widely, even when the pathological characteristics are not typical. The molecular investigation should be performed in infants when a rhabdoid predisposition syndrome is suspected.  相似文献   
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