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21.
Weight loss and catabolic changes are increasingly recognized as factors that influence outcomes in patients with amyotrophic lateral sclerosis (ALS). An association between disease progression and low BMI has been reported in ALS; however, it remains unknown whether low BMI occurs across all forms of ALS and whether BMI changes with the development of cognitive impairment across the spectrum between ALS and frontotemporal dementia (FTD). One hundred and three ALS patients (56 limb predominant, 18 bulbar predominant, 13 ALS plus, 16 ALSFTD) were recruited and compared to 19 behavioral variant FTD (bvFTD) patients and a group of age-matched healthy controls. BMI was measured at the initial clinical visit. Patients were characterized as underweight, normal, overweight or obese, based on the current World Health Organization (WHO) guidelines. Limb and bulbar ALS patients had significantly lower BMI than ALS plus, ALSFTD, and bvFTD patient groups. When BMI was categorized using WHO guidelines the majority of the limb and bulbar ALS patients were either underweight or normal weight, whilst the majority of the ALS plus, ALSFTD and bvFTD patients were either overweight or obese. On follow-up BMI assessment the limb and bulbar groups tended to decline whilst ALS plus, ALSFTD and bvFTD groups remained stable or increased. BMI is significantly higher in ALS individuals with cognitive deficits. The present findings have prognostic implications for disease progression and may help delineate the metabolic profile across the ALSFTD spectrum.  相似文献   
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The objective of this study was to further elucidate the relationship between relevant biological, behavioural, socio-economic and psychological conditions, experienced in very early life and along the life course, and dental caries experience using the life course approach. A two-phase study was carried out in Brazil. In the first phase, 652 13-year-olds were clinically examined and interviewed. In the second phase, 330 families were randomly selected for interview to collect information on the teenagers' early years of life. Clinical assessment included dental caries, periodontal and traumatic dental injury status. The data analysis involved multiple logistic regression analysis. Adolescents born in a non-brick house, those with a low birth weight and those who were the second or later child in the family were statistically significantly more likely to have a high DMF-T. In conclusion, the results of this study show that there is an association between socio-economic and biological factors in very early life and levels of caries in adolescents.  相似文献   
25.
Major depressive disorder (MDD) is associated with risk for chronic pain, but the mechanisms contributing to the MDD and pain relationship are unclear. To examine whether disrupted emotional modulation of pain might contribute, this study assessed emotional processing and emotional modulation of pain in healthy controls and unmedicated persons with MDD (14 MDD, 14 controls). Emotionally charged pictures (erotica, neutral, mutilation) were presented in 4 blocks. Two blocks assessed physiological-emotional reactions (pleasure/arousal ratings, corrugator electromyography (EMG), startle modulation, skin conductance) in the absence of pain and 2 blocks assessed emotional modulation of pain and the nociceptive flexion reflex (NFR, a physiological measure of spinal nociception) evoked by suprathreshold electric stimulations. Results indicated pictures generally evoked the intended emotional responses; erotic pictures elicited pleasure, subjective arousal, and smaller startle magnitudes, whereas mutilation pictures elicited displeasure, corrugator EMG activation, and subjective/physiological arousal. However, emotional processing was partially disrupted in MDD, as evidenced by a blunted pleasure response to erotica and a failure to modulate startle according to a valence linear trend. Furthermore, emotional modulation of pain was observed in controls but not MDD, even though there were no group differences in NFR threshold or emotional modulation of NFR. Together, these results suggest supraspinal processes associated with emotion processing and emotional modulation of pain may be disrupted in MDD, but brain to spinal cord processes that modulate spinal nociception are intact. Thus, emotional modulation of pain deficits may be a phenotypic marker for future pain risk in MDD.  相似文献   
26.
The effects of indomethacin and aspirin on colonic epithelial proliferative activity, colonic prostaglandin synthesis, and colonic mucosal cyclic adenosine 3',5'-monophosphate content were examined. Administration of indomethacin (3 mg/kg.day, s.c.) for 2 wk suppressed ex vivo colonic prostaglandin E2 production by 50% and increased [3H]thymidine incorporation into mucosal DNA in vivo, but induced colonic inflammation. Higher doses of indomethacin were toxic and associated with high mortality. By contrast, administration of aspirin (50 mg/kg.day, s.c.) for 2-20 wk suppressed colonic prostaglandin E2 production by 97% and was unassociated with colonic inflammation or systemic toxicity. Suppression of colonic prostaglandin E2 production was associated with a sustained stimulation of [3H]thymidine incorporation into colonic mucosal deoxyribonucleic acid (2-20 wk) and an increase in the [3H]thymidine labeling index when examined at 20 wk. Basal cyclic adenosine 3',5'-monophosphate content of colonic mucosa was markedly reduced in aspirin-treated rats. Moreover, addition of dimethyl prostaglandin E2 or 8-Br-cyclic adenosine 3',5'-monophosphate suppressed the elevated levels of [3H]thymidine incorporation into mucosal deoxyribonucleic acid in incubated colonic segments from aspirin-treated rats. The results demonstrate that sustained suppression of colonic prostaglandin synthesis by aspirin is associated with a persistent increase in colonic epithelial proliferative activity. They support a role for local colonic prostaglandin synthesis as a negative modulator of epithelial growth, possibly mediated through increases in colonic mucosal cyclic adenosine 3',5'-monophosphate.  相似文献   
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AIM: To determine the presence and nature of amyloid in prostatic corpora amylacea using immunohistological studies. METHODS: Prostatic tissue from 18 transurethral and two open resection specimens was studied. Paraffin wax embedded tissue sections were stained with haematoxylin and eosin and the alkaline Congo red method with and without previous treatment with potassium permanganate. Sections were also stained with antibodies to amyloid A, beta 2 microglobulin, lambda and kappa light chains, prealbumin IgA, G, M, S100 protein, prostatic specific antigen, amyloid P component and CAM 5.2 (control and blocking studies were performed). RESULTS: The prostatic corpora amylacea universally showed the presence of amyloid. In all instances this contained beta 2 microglobulin. CONCLUSION: Prostatic corpora amylacea represents a localised amyloidosis of beta 2 microglobulin origin that is unrelated to chronic renal failure and haemodialysis.  相似文献   
28.
Layer I of the neocortex is a dense synaptic zone consisting of horizontal corticocortical and widespread layer VII projections, in addition to thalamic inputs. In order to determine the origin and extent of corticocortical and thalamocortical projections to layer I of the frontal/premotor area M2 of the rat neocortex, we have used fluorescent anatomical tracing methods to determine the precise sources of cortical and thalamic input to the rostral and caudal aspects of layer I of M2. Retrograde tracer diamidino yellow (DY), applied directly to the pial surface on rostral or caudal areas of rat M2 (RM2 and CM2, respectively) labeled cells ipsilaterally throughout layers II/III, V, and VII of the adjacent primary motor area and the parietal areas (SI and SII). In addition, retrograde transport labeled contralateral CM2 or RM2 in layers II/III and V at sites homotopic to either CM2 or RM2 application sites. Contralateral layer VII was retrogradely labeled by the application to layer I of CM2, but not by the RM2 application. Retrograde DY transport from layer I of RM2 or CM2 of was seen in the ventral medial (VM), ventral lateral (VL), and posterior (Po) thalamic nuclei. However layer I transport from CM2 additionally labeled the thalamic central medial (CM) nucleus, while the RM2 labeled the mediodorsal (MD) thalamic nucleus. Upon determination that thalamic nuclei VM and VL were of primary interest in this study, due to their dense retrograde labeling, injections of anterograde tracer rhodamine dextranamine (RDA) into VM or VL were performed in order to study the projection patterns of these nuclei to layer I of the frontal cortex. RDA injections into VM labeled fibers extending through layer I of both RM2 and CM2 and throughout the cingulate cortex. Injections of RDA into VL consistently labeled dense fibers in layer I of both CM2 and RM2, although labeling was sharply decreased anterior to CM2. This study adds to a growing body of evidence that projections to layer I from all sources of cortical input make a significant contribution to integration throughout the neocortex.  相似文献   
29.
White matter (WM) degeneration in Alzheimer's disease (AD) and mild cognitive impairment (MCI) may be a key indicator of early damage in AD. Here, we analyzed WM diffusion tensor data using Tract-Based Spatial Statistics in conjunction with mixed-effects models. Four indices of diffusion were assessed in 61 healthy control, 19 non-amnestic MCIs, 14 amnestic MCIs, and 9 AD patients. The aim of the study was to use advanced mixed-effects models to investigate the retrogenesis hypothesis of AD, which suggests that tracts that are late to myelinate in ontogenetic development are the earliest to be affected in AD. Our results show that a number of late-myelinating pathways, including the parahippocampal region and the inferior longitudinal fasciculus, were predominantly affected by changes in WM volume. Conversely, early-myelinating pathways were found to be affected by a combination of both WM and gray matter (GM) atrophy. A model of the entire WM structure of the brain returned GM models for two indices of diffusion, suggesting that more complex regional landscapes of diffusion lie hidden beneath a global analysis of the entire brain. Our results warn against an explanation of white matter damage that points simply to one of two mechanisms: secondary degeneration or direct damage of myelin. We suggest that tracts may be affected by both mechanisms, with the balance depending on whether tracts are early or late-myelinating. A greater understanding of the pattern of WM changes in AD may prove useful for the early detection of AD.  相似文献   
30.
HIV prevalence among Chinese men who have sex with men has rapidly increased in recent years. In this randomized, controlled study, we tested the feasibility and efficacy of motivational interviewing to reduce high‐risk sexual behaviors among this population in Changsha, China. Eighty men who have sex with men were randomly assigned to either the intervention group, in which participants received a three‐session motivational interviewing intervention over 4 weeks, or the control group, in which participants received usual counseling from peer educators. High‐risk behavior indicators and HIV knowledge level were evaluated at baseline and 3 months after the intervention. Motivational interviewing significantly improved consistent anal condom use. However, there was no significant change in consistent condom use for oral sex or in the number of sexual partners over time. HIV knowledge scores improved equally in both groups. This study demonstrated that an intervention using motivational interviewing is feasible and results in increased condom use during anal sex for Chinese men who have sex with men. However, further work must be done to increase the use of condoms during oral sexual encounters.  相似文献   
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