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101.
102.
Kinetic evaluation of the pool sizes and proliferative response of neutrophils in bacterially challenged aging mice 总被引:2,自引:0,他引:2
Clinical observations during infection suggest that in aged patients, the kinetic or proliferative responses of neutrophils to infection may be deranged. To test this hypothesis, the neutrophil responses of 6- month-old and 30-month-old mice were compared. After intrapulmonary injection of Escherichia coli, young mice exhibited neutrophilia and diminution of the neutrophil storage pool (NSP) by a mean of 6.4 x 10(6) neutrophils/two femurs. This was accompanied by an increase in the pool of CFU-GM from a control value of 1.1 x 10(5) cells/two femurs (range 0.7 to 1.4) to 1.5 x 10(5) (1.1 to 1.9) (P less than .05) and the thymidine suicide (relative proliferative rate) of CFU-GM rose from 27% (19 to 42) to 51% (31 to 61) (P less than .05). Furthermore, the CFU-GM of infected young mice displayed enhanced differentiation to the neutrophil series. In contrast, old mice exhibited a greater mean diminution of the NSP: 12.8 x 10(6) neutrophils. Also, old mice experienced a reduction in CFU-GM from 2.3 x 10(5) (1.0 to 3.9) (controls) to 1.3 x 10(5) (1.2 to 1.5)/two femurs (P less than .05), a reduction in the proliferation of CFU-GM and reduced differentiation of CFU-GM to neutrophils. These experiments establish that the neutrophil response of infected old mice is disordered, with exaggerated depletion of the NSP and lack of stimulus-driven granulocytopoiesis as reflected by a paradoxical reduction in the number and proliferative rate of precursors. This defect may be compounded by decreased differentiation of precursors to neutrophils. 相似文献
103.
104.
The Effect of a Low Fructose and Low Glycemic Index/Load (FRAGILE) Dietary Intervention on Indices of Liver Function,Cardiometabolic Risk Factors,and Body Composition in Children and Adolescents With Nonalcoholic Fatty Liver Disease (NAFLD) 下载免费PDF全文
Diana R. Mager PhD RD Ingrid Rivera Iñiguez MSc Susan Gilmour MD FRCPC MSc Jason Yap MBChB FRACP 《JPEN. Journal of parenteral and enteral nutrition》2015,39(1):73-84
Background: Nonalcoholic fatty liver disease (NAFLD) is a common liver disease in obese children. Diets high in added fructose (high fructose corn syrup; HFCS) and glycemic index (GI)/glycemic load (GL) are associated with increased risk of NAFLD. Lifestyle modification is the main treatment, but no guidelines regarding specific dietary interventions for childhood NAFLD exist. We hypothesized that reductions in dietary fructose (total, free, and HFCS)/GI/GL over 6 months would result in improvements in body composition and markers of liver dysfunction and cardiometabolic risk in childhood NAFLD. Methods: Children and adolescents with NAFLD (n = 12) and healthy controls (n = 14) 7–18 years were studied at baseline and 3 and 6 months post–dietary intervention. Plasma markers of liver dysfunction (ALT, AST, γGT), cardiometabolic risk (TG, total cholesterol, LDL‐HDL cholesterol, Apo‐B100, Apo‐B48, Apo‐CIII, insulin, homeostasis model of assessment of insulin resistance [HOMA‐IR]), inflammation (TNF‐α, IL‐6, IL‐10), anthropometric, and blood pressure (BP) were studied using validated methodologies. Results: Significant reductions in systolic BP (SBP), percentage body fat (BF), and plasma concentrations of ALT (P = .04), Apo‐B100 (P < .001), and HOMA‐IR were observed in children with NAFLD at 3 and 6 months (P < .05). Dietary reductions in total/free fructose/HFCS and GL were related to reductions in SBP (P = .01), ALT (P = .004), HOMA‐IR (P = .03), and percentage BF in children with NAFLD. Reductions in dietary GI were associated with reduced plasma Apo‐B100 (P = .02) in both groups. With the exception of Apo‐B100, no changes in laboratory variables were observed in the control group. Conclusion: Modest reductions in fructose (total/free, HFCS) and GI/GL intake result in improvements of plasma markers of liver dysfunction and cardiometabolic risk in childhood NAFLD. 相似文献
105.
Christiane Bergamasco RD Lilian Mika Horie RD Raquel Susana Torrinhas BD Dan L. Waitzberg MD PhD 《JPEN. Journal of parenteral and enteral nutrition》2015,39(8):941-947
Background: The daily consumption of dietary fiber is frequently below suggested recommendations. Using a double‐blind, controlled, randomized study, we assessed the efficiency and tolerance of a fiber‐enriched orange juice to supplement fiber intake in women. Materials and Methods: After 1 week of noninterventional observation, 192 healthy adult women ingested 400 mL of orange juice for 21 days, which either was not (placebo group) or was enriched with fiber (fiber group). Orange juice ingestion was registered daily and controlled for each week during the study period. Macronutrient, fiber, and energy intake were determined using a 3‐day food record, validated food chemical composition databases, and the “Pro Diet” software. Gastrointestinal symptoms were self‐evaluated daily by scoring 4 grades of symptom intensity and using a visual analog scale to grade pain severity. Results: No changes were observed for macronutrient and energy ingestion. For the placebo group (n = 97), the total fiber intake record was under the daily recommended value. In contrast, the fiber group (n = 95) displayed higher comparative values of total and soluble fiber consumption (P ≤ .001), achieving the daily recommended values of fiber intake. Both groups reported an increased frequency of slight bloating and rumbles over time (P ≤ .05). The fiber group also experienced a higher frequency of slight flatulence over time (P = .002). Conclusion: Consumption of fiber‐enriched orange juice was efficient to achieve the daily fiber intake recommendation for women, was not accompanied by intense adverse events, and may represent a suitable method to supplement fiber intake in woman. 相似文献
106.
107.
W C Reeves J R Arosemena M Garcia S L de Lao M Cuevas E Quiroz D Caussy W E Rawls 《The Journal of infectious diseases》1989,160(4):599-603
Little is known of the natural history of genital human papillomavirus (HPV) infections in women from high-risk populations. Samples were collected from 183 Panama City prostitutes and assessed for HPV (filter in situ DNA hybridization) and for sexually transmitted agents. The cohort was followed for 8 mo; 51% of subjects completed four monthly return visits and 16% were sampled eight times. The proportion of women found infected with HPV increased significantly with increasing numbers of consecutive samples tested; 38 (21%) of 183 women were positive after one visit and 46 (82%) of 56 who completed six visits were infected. The pattern of viral detection over time was not random, which implied that most prostitutes were persistently infected with genital HPVs and that either scattered foci of infection or periodic reactivation of latent virus occurred. Our findings suggest that multiple sampling is necessary to accurately estimate HPV infection rates and to define whether patterns of DNA expression are present. 相似文献
108.
Halitosis, an offensive breath odour, has multiple sources and negative impacts on people’s social interactions and quality of life. It is important for health care professionals, including general physicians and dental professionals, to understand its aetiology and risk factors in order to diagnose and treat patients appropriately. In this study, we have reviewed the current literature on halitosis regarding its prevalence, classification, risk factors, sources, measurement and treatment. 相似文献
109.
Activation of the coagulation cascade after infusion of a factor XI concentrate in congenitally deficient patients 总被引:5,自引:1,他引:5
Mannucci PM; Bauer KA; Santagostino E; Faioni E; Barzegar S; Coppola R; Rosenberg RD 《Blood》1994,84(4):1314-1319
Virally inactivated, high-purity factor XI concentrates are available for treatment of patients with factor XI deficiency. However, preliminary experience indicates that some preparations may be thrombogenic. We evaluated whether a highly purified concentrate produced signs of activation of the coagulation cascade in two patients with severe factor XI deficiency infused before and after surgery. Signs of heightened enzymatic activity of the common pathway of coagulation (elevated plasma levels of prothrombin fragment 1 + 2 and fibrinopeptide A) developed in the early post-infusion period, accompanied by more delayed signs of fibrin formation with secondary hyperfibrinolysis (elevated D-dimer and plasmin-antiplasmin complex). These changes occurred in both patients, but were more severe in the older patient with breast cancer when she underwent surgery, being accompanied by fibrinogen and platelet consumption. There were no concomitant signs of heightened activity of the factor VII-tissue factor mechanism on the factor Xase complex (plasma levels of activated factor VII and of factor IX and X activation peptides did not increase). The observed changes in biochemical markers of coagulation activation indicate that concentrate infusions increased thrombin generation and activity and that such changes were magnified by malignancy and surgery. Because some factor XI concentrates may be thrombogenic, they should be used with caution, especially in patients with other risk factors for thrombosis. 相似文献
110.
Velimir Matkovic MD PhD Nancy Badenhop-Stevens RD MSc Eun-Jeong Ha PhD Zeljka Crncevic-Orlic MD PhD Albert Clairmont MD 《Clinical reviews in bone and mineral metabolism》2002,1(3-4):233-248
Bone accretion during childhood is proportional to the rate of growth. During this time, interval height velocity is relatively
slow for both boys and girls. As a direct consequence of this, calcium retention in the body of an average child is lower
than the calcium retention in an adolescent. Bone size, bone mass, and bone mineral areal density of the regional skeletal
sites increase on average by about 4%/yr from childhood to late adolescence and young adulthood, when most of the bone mass
is accumulated. Calcium needs are greater during adolescence (pubertal growth spurt) than in childhood or adulthood. According
to calcium balance studies, the threshold in take for adolescents is about 1500 mg/d. Inadequate calcium intake during growth
may increase the risk of childhood fractures and predispose certain individuals to a lower peak bone mass. 相似文献