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101.
OBJECTIVE: To study whether osteopenia occurs following pregnancy and to evaluate its severity in young primiparas. STUDY DESIGN: A prospective case control study. Sixty-one young primigravidae early after birth and 59 nulligravidae matched for age and BMI participated in the study. Bone status was examined using ultrasonic bone transmission velocity over the tibia; Z-score and T-score for bone density were calculated. Serum bone alkaline phosphatase, osteocalcin and urinary N-telopeptide crosslinks were evaluated as bone remodeling biochemical markers. RESULTS: Ultrasonic parameters of bone status following delivery were significantly lower in the puerperal group as compared to the nulligravida group. Serum mean bone alkaline phosphatase levels and urinary N-telopeptide crosslinks secretion were higher by 50% in the puerperal group, while serum osteocalcin levels were significantly lower (by 25%) than in the nulligravida controls. A positive correlation between ultrasonic measurements and biochemical markers was demonstrated in the postpartum group, whereas the control group showed a negative correlation. CONCLUSION: Women at their early puerperium demonstrate a significant cortical bone mass reduction as measured by ultrasonograph and markers of bone turnover. It appears that pregnancy is a state of unbalanced accelerated bone turnover that may be associated with reduced osteoblastic activity.  相似文献   
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Cervical insufficiency is a difficult and confusing diagnosis. Its diagnostic criteria, etiology, and treatment are all debated. Cervical cerclage has been a common practice in obstetrics since it was first described by Shirodker and then McDonald in the 1950s. Cerclages have been placed because of a patient's obstetrical history, physical examination, ultrasound, or a combination of the above. However, the data supporting cerclage placement is limited. There has never been a prospective, randomized, controlled trial of cerclage versus no cerclage in patients with a classic history of cervical insufficiency (multiple painless second trimester losses occurring at progressively earlier gestational ages). This article attempts to review the relevant studies regarding cerclage placement for the treatment of cervical insufficiency. Based on the current literature, there is evidence supporting cervical cerclage in the following limited circumstances: a history of 3 or more spontaneous preterm births or second trimester losses; a high-risk patient with a singleton pregnancy who has a short cervix in the second trimester. Because the majority of patients with risk factors for preterm birth and second trimester loss (poor obstetric history, short cervix) will still deliver at term or near-term, studies on the effectiveness of cervical cerclage would need many patients to be powered appropriately.  相似文献   
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While Ayurvedic medicine has touted the cognitive enhancing effects of Bacopa monniera for centuries, there is a need for double-blind placebo-controlled investigations. One hundred and seven healthy participants were recruited for this double-blind placebo-controlled independent group design investigation. Sixty-two participants completed the study with 80% treatment compliance. Neuropsychological testing using the Cognitive Drug Research cognitive assessment system was conducted at baseline and after 90 days of treatment with a special extract of Bacopa monniera (2 x 150 mg KeenMind) or placebo. The Bacopa monniera product significantly improved performance on the 'Working Memory' factor, more specifically spatial working memory accuracy. The number of false-positives recorded in the Rapid visual information processing task was also reduced for the Bacopa monniera group following the treatment period. The current study provides support for the two other published studies reporting cognitive enhancing effects in healthy humans after a 90 day administration of the Bacopa monniera extract. Further studies are required to ascertain the effective dosage range, the time required to attain therapeutic levels and the effects over a longer term of administration.  相似文献   
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OBJECTIVE: Fetal fibronectin (fFN) has a high negative predictive value for delivery in the next seven days in patients at risk for preterm birth. Providers sometimes disregard a negative result and manage the patient for threatened preterm labor. Our objective was to identify the rate at which patients with a negative fFN were managed for threatened preterm labor and if delivery outcomes were improved with such management. STUDY DESIGN: Retrospective chart review of 111 patients at a single institution evaluated in the obstetrical triage unit for symptoms of threatened preterm labor with negative fFN results over a 19-month period between November 2004 and June 2006. Charts were reviewed for baseline patient characteristics such as gestational age at presentation to triage and fFN testing, prior obstetrical history, cervical examination and contraction frequency. Gestational age at delivery was documented. Rates of admission to the hospital and treatments for threatened preterm labor in this cohort were reviewed. RESULTS: Thirty-seven of patients (33%) with a negative fFN result were managed for threatened preterm labor (admitted to the hospital, given tocolytics, steroids, or intravenous antibiotics) by their provider. Patients undergoing these interventions were more likely to have cervical dilatation, effacement and were contracting more frequently. Only one of the patients delivered within 7 or 14 days of fFN testing. There was no advantage seen to management of threatened preterm labor in the setting of a negative fFN in terms of pregnancy prolongation, even when analyzing the patients with meaningful clinical findings (dilated 2 cm, effaced >or=80%, or contracting >or=12 times/h). CONCLUSION: Patients with meaningful clinical findings suspicious for preterm labor are more likely to undergo interventions by their physicians in the face of a negative fFN. This management does not improve length of gestation.  相似文献   
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The changes in the distribution of intravenously administered colloidal ink in splenectomized rabbits may be interpreted somewhat as follows: The removal of the spleen throws an increased amount of ink into the other hematopoietic organs and the lung and liver. While we should expect the liver or the bone marrow to compensate for the loss of the spleen and to take up this ink and remove it from the circulation, that is not the case. The lungs appear to play the chief part in the process, slowly passing on the removed material, contained in macrophages, to the liver, or retaining these ink-laden cells in their tissues and capillaries. By an increase in the capillary endothelium and by a process of engorgement of the capillaries with cells presumably derived therefrom, the lungs remove by far the greater part of the foreign material that has been introduced into the circulation. At the same time there is an increase in the number of ink-bearing macrophages in the lymphatics and capillaries of the lung, indicating that these cells are entering the circulation and the lymph stream (Fig. 8). The only organ where they lodge in any quantities, outside of the peribronchial lymph nodes, is the liver, the sinusoids of which contain an increasing number of macrophages as time goes on. It is possible that these cells are destroyed in the sinusoids and the carbon transferred to the liver epithelium; there is evidence to support this assumption. After the lungs, the liver comes next in degree of intensity of pigmentation; the bone marrow contains far less than either of these organs.  相似文献   
109.
Increases in snack consumption associated with Westernized lifestyles provide an opportunity to introduce nutritious foods into poor diets. We describe two 10-wk-long open label, single group assignment human studies that measured the effects of two snack prototypes containing fiber preparations from two sustainable and scalable sources; the byproducts remaining after isolation of protein from the endosperm of peas and the vesicular pulp remaining after processing oranges for the manufacture of juices. The normal diets of study participants were supplemented with either a pea- or orange fiber-containing snack. We focused our analysis on quantifying the abundances of genes encoding carbohydrate-active enzymes (CAZymes) (glycoside hydrolases and polysaccharide lyases) in the fecal microbiome, mass spectrometric measurements of glycan structures (glycosidic linkages) in feces, plus aptamer-based assessment of levels of 1,300 plasma proteins reflecting a broad range of physiological functions. Computational methods for feature selection identified treatment-discriminatory changes in CAZyme genes that correlated with alterations in levels of fiber-associated glycosidic linkages; these changes in turn correlated with levels of plasma proteins representing diverse biological functions, including transforming growth factor type β/bone morphogenetic protein-mediated fibrosis, vascular endothelial growth factor-related angiogenesis, P38/MAPK-associated immune cell signaling, and obesity-associated hormonal regulators. The approach used represents a way to connect changes in consumer microbiomes produced by specific fiber types with host responses in the context of varying background diets.

Advances in our understanding of the role of the gut microbiome in regulating many aspects of human physiology hold the promise of evolving our view of human nutrition by establishing mechanistic connections between the foods we consume and how they affect health status. One manifestation of this effort is a series of studies, performed on well-phenotyped cohorts, that seek to relate features of gut microbial community composition (organisms, genes), dietary practices, and pre- and postprandial cardiometabolic responses to test meals (14). A key question raised by these initiatives relates to the nature of the “bioactive” components of foods. Specifically, what are the nutrients utilized by various gut community members or microbiome-encoded metabolic pathways? What products are produced by biotransformation of these nutrients? How are these products linked to specific host physiologic (or pathophysiologic) processes?Plant-derived dietary fibers represent a “poster child” for these efforts and illustrate the formidable challenges faced. The health benefits of dietary fibers are widely known, as is their inadequate representation in Western diets. However, natural fibers are structurally complex and highly diverse. They contain numerous, typically undefined polysaccharide structures and largely unspecified protein, lipid, and small molecule constituents. Their composition varies as a function of their origin (food staple and cultivar), the different methods employed to recover them from these sources, as well as the different techniques used to incorporate them into processed foods with acceptable organoleptic properties (5). Moreover, analyzing the host effects of metabolism of different fibers is confounded by the fact that there is substantial intra- and interpersonal variation in microbiome configuration (6, 7).Snacking is becoming an ever more dominant feature of daily life worldwide and thus provides an opportunity to introduce nutritious ingredients, such as fibers, into diets. However, obtaining structure-activity relationships for specific fiber types and their corresponding targets in the gut community is foundational for designing snack foods that evoke and/or reinforce microbiome responses that are beneficial to the host.Degradation of dietary polysaccharides is a function primarily performed by bacterial carbohydrate-active enzymes (CAZymes). The gut microbiome harbors tens of thousands of CAZyme genes belonging to at least 136 glycoside hydrolase (GH) and 29 polysaccharide lyase (PL) families [extrapolated and updated from El Kaoutari et al. (8)]. In contrast, the human genome only contains 98 GH and no PL genes (9), of which <20% contribute to the processing of dietary glycans.In the current study, we test the effects of dietary supplementation with two snack food prototypes, one containing pea fiber and the other orange fiber, in two pilot studies of overweight and obese individuals consuming their normal, unrestricted diets. Our strategy was to focus on fiber-associated changes in the abundances of microbial GH and PL genes to determine whether responses to the pea or orange fiber prototypes in the gut microbiome and host are decipherable against a background of varying dietary practices and starting microbiome configurations. Higher order singular value decomposition (10) was utilized as a feature selection tool to identify treatment-discriminating changes in GH and PL gene representation. Mass spectrometric assays of the levels of fecal glycan structures (glycosidic linkages) were subsequently performed and the results were correlated with changes in the abundances of treatment-discriminating GH and PL genes with known or predicted substrate specificities. Our analysis concluded by measuring changes in levels of 1,305 plasma proteins in each study participant as a function of fiber treatment and applying computational tools to identify links between these microbiome and plasma proteome changes in response to fiber consumption. Our results provide an approach, using pilot human studies, for selecting specific fiber preparations, plus informative microbiome and host biomarkers, that can be advanced to proof-of-concept clinical trials which assess their capacity for precise manipulation of microbiome and host features.  相似文献   
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