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991.
Stephen Houghton John Hattie Lisa Wood Annemaree Carroll Karen Martin Carol Tan 《Child psychiatry and human development》2014,45(5):604-616
This paper reports the development and psychometric evaluations of a multidimensional model of loneliness in Australian adolescents. In the first study a new instrument was designed and administered to 1,074 adolescents (ages 10–18 years, M = 13.01). An exploratory factor analysis from data supplied by 694 of these participants yielded a 4-factor structure (friendship, isolation, negative attitude to solitude, and positive attitude to solitude). Competing measurement models were then evaluated using confirmatory factor analysis with data from the remaining 380 participants; strong support was demonstrated for the conceptual model. Significant main effects were evident for geographical location (rural remote/urban), age and sex. In a second study, involving 235 Australian adolescents (ages 10.0–16 years, M = 13.8) the superiority of the first-order model represented by four correlated factors was confirmed. The findings have clinical and practical implications for professional groups represented by child and adolescent psychiatry, pediatric and clinical psychology services, researchers, and educators. Specifically, the new self-report instrument identifies adolescents who are at risk of loneliness and its associated adverse outcomes and in doing has the potential to offer new insights into prevention and intervention. 相似文献
992.
Devender Bhalla Achille Edem Tchalla Benoît Marin Edgard Brice Ngoungou Chong Tin Tan Pierre‐Marie Preux 《Epilepsia》2014,55(9):1317-1321
Is epilepsy truly an “African ailment”? We aimed to determine this, since international health agencies often refer to epilepsy as an African disease and the scientific literature has spoken the same tone. Various published materials, mainly reports, articles, were used to gather Asian and African evidence on various aspects of epilepsy and many of its risk and associated factors. Our results suggest that in no way can epilepsy be considered as an African ailment and such characterization is most likely based on popular beliefs rather than scientific evidence. In comparison to Africa, Asia has a 5.0% greater burden from all diseases, and is 17.0% more affected from neuropsychiatric disorders (that include epilepsy). Given that more countries in Asia are transitioning, there may be large demographic and lifestyle changes in the near future. However these changes are nowhere close to those expected in Africa. Moreover, 23 million Asians have epilepsy in comparison to 3.3 million Africans and 1.2 million sub‐Saharan Africans. In comparison to Africa, Asia has more untreated patients, 55.0% more additional epilepsy cases every year, because of its larger population, with greater treatment cost and possibly higher premature mortality. Of several associated factors discussed herein, many have more importance for Asia than Africa. The current state of epilepsy in Asia is far less than ideal and there is an urgent need to recognize and accept the importance of epilepsy in Asia. In no way can epilepsy be considered as an African ailment. This is most likely based on popular beliefs rather than scientific evidence. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here . 相似文献
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996.
Qiu Q Bell M Lu X Yan X Rodger M Walker M Wen SW Bainbridge S Wang H Gruslin A 《The Journal of clinical endocrinology and metabolism》2012,97(8):E1429-E1439
Background: Fetal growth restriction (FGR) is a leading cause of perinatal mortality and morbidity. Animal studies suggest dysregulation of IGF-binding protein (IGFBP)-4 is significant in the development of FGR, although human data are lacking. We postulated that IGFBP-4 is expressed at the maternal fetal interface and plays a role in regulating IGF bioavailability. Thus, maternal serum levels of IGFBP-4 may be associated with complications of abnormal placental growth and development including FGR. Methods: Circulating levels of IGFBP-4 and its protease, pregnancy-associated plasma protein-A (PAPP-A), were examined in healthy pregnancies. Their expression in villi and bed as possible sources of the circulating products were examined by immunohistochemistry. From the large Ottawa and Kingston (OaK) Birth Cohort, a nested case-control study was conducted to examine circulating levels of IGBP-4, PAPP-A, IGF-I, and IGF-II by Western blot in early gestation in 36 women who went on to develop FGR and 36 controls having normal-weight babies. Results: IGFBP-4 was elevated in early pregnancy compared with nonpregnant women and women in later pregnancy, consistent with the presence of abundant extravillous trophoblasts and decidual cells that highly expressed IGFBP-4. High expression of PAPP-A was observed in extravillous trophoblasts and decidual cells in early pregnancy but hardly detectable in the circulation at this time, suggesting maternal circulating PAPP-A originates more likely from syncytiotrophoblasts. Increased IGFBP-4 in the maternal circulation in early pregnancy was associated with the development of FGR [0.48 (0.28-0.74) in control vs. 1.22 (0.66-1.65) in FGR; odds ratio = 22 (95% confidence interval = 2.7-181)]. No difference was observed in circulating PAPP-A, IGF-I and IGF-II in the FGR vs. control group. Conclusion: Our findings support the role of IGFBP-4 in regulating IGF bioavailability and provide new clues for the prevention and treatment of FGR, raising the possibility of clinical use of IGFBP-4 as an early biomarker for this condition. 相似文献
997.
998.
Tan LA Chand D De Almeida R Xu M De Lannoy L Lovejoy DA 《General and comparative endocrinology》2012,176(3):309-313
The co-evolution of peptides and early cells some 3.7 billion years ago provided bioactive peptides with a long history for the proliferation and refinement of peptide hormones. Central to the adaptation and evolution of cell types in metazoans is the development of peptide signaling systems that regulate stress mechanisms. The corticotropin-releasing factor (CRF) family of peptides represents the canonical family of peptides that are pivotal to the regulation of stress in vertebrates. However, these peptides appear to have evolved at least 2 billion years after the formation of the first postulated bioactive peptides, suggesting that before this, other peptide systems played a role in stress and energy metabolism. The teneurin C-terminal associated peptides (TCAPs) are a recently discovered family of highly conserved peptides that are processed from the teneurin transmembrane proteins. This peptide/protein system is ubiquitous in multicellular organisms and evolved before the CRF family. TCAP-1 is a potent regulator of CRF-associated physiology and behavior and may play a significant role in the regulation of cell-to-cell communication and neuroplasticity in neurons. 相似文献
999.
Wang F Tan Y Wang C Zhang X Zhao Y Song X Zhang B Guan Q Xu J Zhang J Zhang D Lin H Yu C Zhao J 《The Journal of clinical endocrinology and metabolism》2012,97(8):2724-2731
Context and Objective: Dyslipidemia in thyroid dysfunction has always been attributed to changes in thyroid hormone (TH) levels. We hypothesized that TSH plays an important role in lipid metabolism independent of TH. Design and Setting: We conducted a cross-sectional study to investigate the relationship between serum TSH levels and lipid profiles after controlling for free T(3), free T(4), total T(3), total T(4) and nonthyroid factors relevant to lipid metabolism in euthyroid Chinese subjects. Main Outcome Measures: General linear analysis was performed to determine whether the impact of TSH on serum lipid levels is independent of the TH levels. Moreover, path analysis, an evolutionary multivariable regression technique, was conducted to test whether there is a direct and/or indirect effect between serum TSH and total cholesterol (TC) levels. Additionally, the odds ratios (95% confidence interval) for hypercholesterolemia in relation to TSH categories were calculated. Results: A total of 3664 euthyroid subjects were finally analyzed. There was a significant linear trend toward higher log TC (P = 0.021) and log triglyceride (P = 0.001) levels with increasing serum TSH levels within the reference range, which remained significant after adjusting for factors such as TH levels, age, and smoking. Most importantly, the total effect of TSH on TC levels (total effect(TC, TSH) = 0.05253) includes a direct effect (direct effect(TC, TSH) = 0.05979) and an indirect effect via TH. Compared with subjects in the lower part of the reference range (TSH level, 0.27-0.61 mIU/liter), the adjusted odds ratio for hypercholesterolemia was 3.239 (95% confidence interval, 1.392-7.538; P = 0.007) for those in the upper category (TSH level, 4.61-5.5 mIU/liter). Conclusions: The variation in normal TSH levels is partially related to the lipid components and hypercholesterolemia in euthyroid subjects and includes both TH-dependent and TH-independent effects. Our study suggests the importance of controlling TSH in hypothyroid subjects. 相似文献
1000.
Hernández-Rodríguez J Tan CD Koening CL Khasnis A Rodríguez ER Hoffman GS 《Medicine》2012,91(2):75-85
Testicular vasculitis (TV) may be part of systemic (testicular) vasculitis (STV) or may exist as single-organ/isolated (testicular) vasculitis (ITV). In the current study we sought to identify clinical and histologic features that distinguish STV from ITV. The distinction was deemed important because it is already well established that in other forms of single organ vasculitis, surgical therapy alone may be curative. We identified patients with biopsy-proven TV from pathology databases from our institution and from an English-language PubMed search. Patients were included if data were available to determine TV extent confidently. Data recorded included clinical, laboratory, and histologic features; treatment; and clinical follow-up. The study included 72 patients with TV (mean age, 42 yr; range, 4-78 yr) (7 from our institution). About 74% of patients presented with painful testicular swelling/mass, 10% with a painless testicular swelling/mass, and 4% with epididymal swelling/mass. Eleven percent had no testicular complaints and vasculitis was discovered at autopsy or in other surgical interventions. Vasculitis involved the testicle in 80.3% of cases, the epididymis in 44.6%, and the spermatic cord in 30.6%. Thirty-seven (51%) patients had ITV and 35 (49%) had STV. No differences between ITV and STV patients were found in regards to age, presenting testicular features, duration of testicular symptoms, and time of follow-up. Compared to ITV patients, STV patients presented more often with constitutional/musculoskeletal symptoms (74.3% vs. 8.3%, respectively; p = 0.0001), elevated erythrocyte sedimentation rate (94.7% vs. 16%; p = 0.0001), and anemia (50% vs. 0%; p = 0.0001). Neoplasm was more frequently suspected in ITV than in STV (74.2% vs. 31.6%; p = 0.001), but only occurred in 2 ITV patients. Long-term glucocorticoid therapy was given only to STV patients, and 59.1% of them also received cytotoxic agents. ITV was diagnosed more often by orchiectomy (81.1% vs. 42.9%; p = 0.001) and less frequently by testicular biopsy (2.7% vs. 28.6%; p = 0.003) than STV. Nongranulomatous inflammation affecting medium-sized vessels occurred in most patients with both ITV and STV. Among STV, polyarteritis nodosa was the most frequently diagnosed (63%), followed by Wegener granulomatosis (17%).In summary, TV occurs as ITV in men usually presenting with a testicular mass in the absence of systemic symptoms and normal laboratory results. In most ITV patients, a testicular neoplasm is initially suspected, and TV is an unexpected finding. After surgical removal, ITV does not require systemic therapy. Polyarteritis nodosa is the systemic vasculitis most frequently associated with testicular involvement. 相似文献