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61.

Aim

Postprandial secretion of the appetite-inhibiting hormones, glucagon-like peptide-1 (GLP-1), and peptide YY are reduced with obesity. It is unclear if the reduced secretion persists following weight loss (WL), if other appetite-inhibiting hormones are also reduced, and if so whether reduced secretion results from intrinsic changes in the gut.

Methods

To address whether WL may restore secretion of GLP-1 and other appetite-inhibiting hormones, we performed a gut perfusion study of the small intestine in diet-induced obese (DIO) rats after WL. A 20% weight loss (means ± SEM (g): 916 ± 53 vs. 703 ± 35, p < 0.01, n = 7) was induced by calorie restriction, and maintained stable for ≥7 days prior to gut perfusion to allow for complete renewal of enteroendocrine cells. Age-matched DIO rats were used as comparator. Several gut hormones were analyzed from the venous effluent, and gene expression was performed on gut tissue along the entire length of the intestine.

Results

Secretion of cholecystokinin, gastrin, glucose-dependent insulinotropic peptide, GLP-1, neurotensin, and somatostatin was not affected by WL during basal conditions (p ≥ 0.25) or in response to macronutrients and bile acids (p ≥ 0.14). Glucose absorption was indistinguishable following WL. The expression of genes encoding the studied peptides, macronutrient transporters (glucose, fructose, and di-/tripeptides) and bile acid receptors did also not differ between DIO and WL groups.

Conclusions

These data suggest that the attenuated postprandial responses of GLP-1, as well as reduced responses of other appetite-inhibiting gut hormones, in people living with obesity may persist after weight loss and may contribute to their susceptibility for weight regain.  相似文献   
62.
The expression of the protooncogenes ETS1 and ETS2 has been studied in purified human T cells activated either by cross-linking of the T-cell receptor-CD3 complex on their cell surface or by direct stimulation with phorbol esters and ionomycin. Our results show that resting T cells express high levels of ETS1 mRNA and protein, while expression of ETS2 is undetectable. Upon T-cell activation, ETS2 mRNA and proteins are induced, while ETS1 gene expression decreases to very low levels. Late after stimulation, ETS1 mRNA is reinduced and maintained at a high level, while ETS2 gene expression decreases to undetectable levels. Therefore, it appears that in human T cells, ETS2 gene products are associated with cellular activation and proliferation, while ETS1 gene products are preferentially expressed in a quiescent state.  相似文献   
63.
Previous structural and functional neuroimaging studies have implicated distributed brain regions and networks in depression. However, there are no robust imaging biomarkers that are specific to depression, which may be due to clinical heterogeneity and neurobiological complexity. A dimensional approach and fusion of imaging modalities may yield a more coherent view of the neuronal correlates of depression. We used linked independent component analysis to fuse cortical macrostructure (thickness, area, gray matter density), white matter diffusion properties and resting‐state functional magnetic resonance imaging default mode network amplitude in patients with a history of depression (n = 170) and controls (n = 71). We used univariate and machine learning approaches to assess the relationship between age, sex, case–control status, and symptom loads for depression and anxiety with the resulting brain components. Univariate analyses revealed strong associations between age and sex with mainly global but also regional specific brain components, with varying degrees of multimodal involvement. In contrast, there were no significant associations with case–control status, nor symptom loads for depression and anxiety with the brain components, nor any interaction effects with age and sex. Machine learning revealed low model performance for classifying patients from controls and predicting symptom loads for depression and anxiety, but high age prediction accuracy. Multimodal fusion of brain imaging data alone may not be sufficient for dissecting the clinical and neurobiological heterogeneity of depression. Precise clinical stratification and methods for brain phenotyping at the individual level based on large training samples may be needed to parse the neuroanatomy of depression.  相似文献   
64.
A modification of the in vitro culture ofmarrow cells in soft agar to form granulocyte-monocyte colonies has been applied to human marrow using a constantstimulus of colony-stimulating factor (CSF)in the form of pooled serum from endotoxin-treated C57BL mice (EMS). With thissystem reproducible increments in colonyformation were observed between twoconcentrations of EMS. The results indicate that the incremental response to twodoses of CSF (CSF response ratio) combined with an observation of the numberof colonies formed provide a more reliablemeasurement of colony-forming cells(CFC) than colony counts at a single doselevel of CSF. The CSF response ratio in43 marrow cultures from 34 patients withno obvious disturbance in granulopoiesiswas found to be 1.65 (± 0.17 SD). Hodgkin’s disease with normal marrow showeda mean CSF response ratio of 2.04. Twosubjects recovering from drug-inducedagranulocytosis showed increased CSFresponse at a time when the blood wasstill neutropenic and the marrow showedhyperplasia and immaturity of the granulocytic tissue. In contrast, patients withsustained neutropenia and impaired marrow granulopoiesis showed CSF responseratios of less than 1.65. CSF responseratios in chronic myelogenous leukemiaaveraged 1.72, often with extremely highnumbers of colonies per plate. Patientswith untreated acute leukemia and marrows replaced by blasts did not formcolonies. However, with partial leukemicmarrow replacement, lymphoblastic leukemia marrow formed more colonies thandid that of myeloblastic leukemia.

Submitted on September 30, 1972 Revised on April 9, 1973 Accepted on May 12, 1973  相似文献   
65.
We report evidence that auditory verbal hallucinations (AVH) in schizophrenia patients are perceptual distortions lateralized to the left hemisphere. We used a dichotic listening task with repeated presentations of consonant-vowel syllables, a different syllable in the right and left ear. This task produces more correct reports for the right ear syllable in healthy individuals, indicative of left hemisphere speech processing focus. If AVHs are lateralized to the left hemisphere language receptive areas, then this should interfere with correct right ear reports in the dichotic task, which would result in significant negative correlations with severity of AVHs. We correlated the right and left ear correct reports with the PANSS hallucination symptom, and a randomly selected negative symptom, in addition to the sum total of the positive and negative symptoms, in 160 patients with schizophrenia. The results confirmed the predictions with significant negative correlations for the right ear scores with the PANSS hallucination item, and for the sum total of positive symptoms, while all other correlations were close to zero. The results are unambiguous evidence for AVHs as aberrant speech perceptions originating in the left hemisphere.  相似文献   
66.

Introduction and hypothesis

The aim of this study was to investigate the association between patient age at the time of hysterectomy and subsequent pelvic organ prolapse (POP) surgery.

Methods

We gathered data on all benign hysterectomies and POP surgeries performed in Denmark on Danish women from 1977 to 2009 from the Danish National Patient Registry. The cohort consisted of 154,882 hysterectomized women, who were followed up for up to 32 years. Survival analysis for each age group at hysterectomy was performed using Kaplan–Meier product limit methods.

Results

For all hysterectomized women, we found that low age at hysterectomy yielded a lower risk of subsequent POP surgery than did hysterectomy at an older age. This difference diminished after stratification by indication; all non-POP hysterectomies had a low cumulative incidence at 8–11 % at the end of the follow-up period. For all women hysterectomized, the predominant compartment for POP surgery was the posterior. Women hysterectomized when aged over 66 years had a higher proportion of POP surgery in the apical compartment than in the other age groups (p?=?0.000).

Conclusion

Our findings indicate that age at hysterectomy only marginally influences the risk of subsequent POP surgery for women hysterectomized for indications other than POP. If POP is the indication for hysterectomy, the risk of undergoing subsequent POP surgery increases substantially.
  相似文献   
67.
The aim of this study was to evaluate the effect of photodynamic therapy with topical methylaminolevulinate for the treatment of basal cell carcinomas in a single dermatological department. Ninety patients (34.4% men and 65.6% women) with a total of 157 basal cell carcinomas (111 superficial, 40 nodular, 6 unknown) were treated. Primary endpoint was clinically observed recurrence verified by biopsy 3, 6 and 12 months after treatment, then once a year. Estimated patient recurrence rates were 7% at 3 months, 19% at 6 months, 27% at 12 months and 31% at 24 months. Patients aged over 60 years had significantly higher estimated recurrence rates compared with patients aged 60 years or under (at 12 months, 35% vs. 19%, p?=?0.01). Estimated recurrence rates for tumours was 4% at 3 months, 11% at 6 months, 16% at 12 months and 19% at 24 months. There were significantly higher estimated recurrence rates for nodular basal cell carcinomas compared with superficial basal cell carcinomas (at 12 months, 28% vs. 13%, p?=?0.008). In conclusion, photodynamic therapy is only appropriate for treatment of superficial basal cell carcinoma, and, age above 60 years and histology showing nodular basal cell carcinoma are independent risk factors for developing a recurrent basal cell carcinoma.  相似文献   
68.
OBJECTIVE: Evaluate the physical fitness and training of Norwegian infantry soldiers during 10 months of compulsory military service. METHODS: Maximal oxygen uptake (VO2max) and maximal numbers of sit-ups, push-ups, and chin-ups and 3-km running time were tested in 107 male infantry soldiers at the beginning and end of basic training (BT), and again at demobilization. The amount of physical training was registered throughout the military service. RESULTS: During BT, major improvements in sit-ups and push-ups were found. VO2max increased in soldiers with the lowest initial VO2max, but decreased to pre-BT level at demobilization. The amount of obligatory physical training was 8.5 hours x week(-1) during BT and 35% lower after BT, and was usually performed in uniform at low to moderate intensity. CONCLUSION: The amount of high-intensity endurance and strength training during compulsory military service is to low to improve the soldiers' endurance and muscular strength.  相似文献   
69.
During the oestrus cycle, varying spine synapse density correlates positively with varying local synthesis of oestradiol in the hippocampus. In this context, the roles of the oestrogen receptor (ER) subtypes ERα and β are not fully understood. In the present study, we used neonatal hippocampal slice cultures from female rats because these cultures synthesise oestradiol and express both receptor subtypes, and inhibition of oestradiol synthesis in these cultures results in spine synapse loss. Using electron microscopy, we tested the effects on spine synapse density in response to agonists of both ERα and ERβ. Application of agonists to the cultures had no effect. After inhibition of oestradiol synthesis, however, agonists of ERα induced spine synapse formation, whereas ERβ agonists led to a reduction in spine synapse density in the CA1 region of these cultures. Consistently, up‐regulation of ERβ in the hippocampus of adult female aromatase‐deficient mice is paralleled by hippocampus‐specific spine synapse loss in this mutant. Finally, we found an increase in spine synapses in the adult female ERβ knockout mouse, but no effect in the adult female ERα knockout mouse. Our data suggest antagonistic roles of ERβ and ERα in spine synapse formation in the female hippocampus, which may contribute to oestrus cyclicity of spine synapse density in the hippocampus.  相似文献   
70.

Introduction

In North Africa and the Middle East, studies about dementia prevalence are scarce. A pilot study was conducted in Lebanon to assess dementia prevalence, using the Arabic-validated 10/66 Dementia Research Group (DRG) diagnostic assessment for case ascertainment. The study also examined care arrangement and access to care.

Methods

A random sample of 502 persons older than 65 years and their informant were recruited from Beirut and Mount Lebanon governorates through multistage cluster sampling.

Results

The crude and age-standardized dementia prevalences were 7.4% and 9.0%, respectively. People with dementia were mainly cared for by relatives at home. Access to formal care was very limited.

Discussion

Dementia prevalence in Lebanon ranks high within the global range of estimates. These first evidence-based data about disease burden and barriers to care serve to raise awareness and call for social and health care reform to tackle the dementia epidemic in Lebanon and in North Africa and the Middle East.  相似文献   
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