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191.
Fruits and vegetables containing phenylalanine ≤ 75 mg/100 g (except potatoes) have little impact on blood phenylalanine in phenylketonuria (PKU). In a randomized, controlled, crossover intervention trial, we examined the effect of increasing phenylalanine intake from fruits and vegetables, containing phenylalanine 76–100 mg /100 g, compared with milk protein sources on blood phenylalanine control. This was a five-phase study (4 weeks each phase). In Phase A, patients remained on their usual diet and then were randomly allocated to start Phase B and C (an additional phenylalanine intake of 50 mg/day, then 100 mg from fruits and vegetables containing phenylalanine 76–100 mg/100 g) or Phase D and E (an additional phenylalanine intake of 50 mg/day then 100 mg/day from milk sources). There was a 7-day washout with the usual phenylalanine-restricted diet between Phase B/C and D/E. Blood phenylalanine was measured on the last 3 days of each week. If four out of six consecutive blood phenylalanine levels were >360 μmol/L in one arm, this intervention was stopped. Sixteen patients (median age 10.5 y; range 6–12 y) were recruited. At baseline, a median of 6 g/day (range: 3–25) natural protein and 60 g/day (range: 60–80) protein equivalent from protein substitute were prescribed. Median phenylalanine levels were: Phase A—240 μmol/L; Phase B—260 μmol/L; Phase C—280 μmol/L; Phase D—270 μmol/L and Phase E—280 μmol/L. All patients tolerated an extra 50 mg/day of phenylalanine from fruit and vegetables, containing phenylalanine 76–100 mg/100 g, but only 11/16 (69%) tolerated an additional 100 mg /day. With milk protein, only 8/16 (50%) tolerated an extra 50 mg/day and only 5/16 (31%) tolerated an additional 100 mg/day of phenylalanine. Tolerance was defined as maintaining consistent blood phenylalanine levels < 360 μmol/L throughout each study arm. There was a trend that vegetable protein had less impact on blood phenylalanine control than milk protein, but overall, the differences were not statistically significant (p = 0.152). This evidence supports the PKU European Guidelines cutoff that fruit and vegetables containing 76–100 mg phenylalanine/100 g should be calculated as part of the phenylalanine exchange system. Tolerance of the ‘free use’ of these fruits and vegetables depends on inter-patient variability but cannot be recommended for all patients with PKU.  相似文献   
192.
Emerging data support the pivotal role of extracellular vesicles (EVs) in normal cellular physiology and disease conditions. However, despite their abundance, there is much less information about the lipid mediators carried in EVs, especially in the context of acute lung injury (ALI). Our data demonstrate that C57BL/6 mice subjected to intranasal Escherichia coli lipopolysaccharide (LPS)-induced ALI release, a higher number of EVs into the alveolar space, compared to saline-treated controls. EVs released during ALI originated from alveolar epithelial cells, macrophages, and neutrophils and carry a diverse array of lipid mediators derived from ω-3 and ω-6 polyunsaturated fatty acids (PUFA). The eicosanoids in EVs correlated with cellular levels of arachidonic acid, expression of cytosolic phospholipase A2, cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome epoxygenase p450 proteins in pulmonary macrophages. Furthermore, EVs from LPS-toll-like receptor 4 knockout (TLR4<sup>-/-</sup>) mice contained significantly lower amounts of COX and LOX catalyzed eicosanoids and ω-3 PUFA metabolites. More importantly, EVs from LPS-treated wild-type mice increased TNF-α release by macrophages and reduced alveolar epithelial monolayer barrier integrity compared to EVs from LPS-treated TLR4<sup>−/−</sup> mice. In summary, our study demonstrates for the first time that the EV carried PUFA metabolite profile in part depends on the inflammatory status of the lung macrophages and modulates pulmonary macrophage and alveolar epithelial cell function during LPS-induced ALI.  相似文献   
193.
Abrin is a highly toxic protein obtained from the seeds of the rosary pea plant Abrus precatorius, and it is closely related to ricin in terms of its structure and chemical properties. Both toxins inhibit ribosomal function, halt protein synthesis and lead to cellular death. The major clinical manifestations following pulmonary exposure to these toxins consist of severe lung inflammation and consequent respiratory insufficiency. Despite the high similarity between abrin and ricin in terms of disease progression, the ability to protect mice against these toxins by postexposure antibody-mediated treatment differs significantly, with a markedly higher level of protection achieved against abrin intoxication. In this study, we conducted an in-depth comparison between the kinetics of in vivo abrin and ricin intoxication in a murine model. The data demonstrated differential binding of abrin and ricin to the parenchymal cells of the lungs. Accordingly, toxin-mediated injury to the nonhematopoietic compartment was shown to be markedly lower in the case of abrin intoxication. Thus, profiling of alveolar epithelial cells demonstrated that although toxin-induced damage was restricted to alveolar epithelial type II cells following abrin intoxication, as previously reported for ricin, it was less pronounced. Furthermore, unlike following ricin intoxication, no direct damage was detected in the lung endothelial cell population following abrin exposure. Reduced impairment of intercellular junction molecules following abrin intoxication was detected as well. In contrast, similar damage to the endothelial surface glycocalyx layer was observed for the two toxins. We assume that the reduced damage to the lung stroma, which maintains a higher level of tissue integrity following pulmonary exposure to abrin compared to ricin, contributes to the high efficiency of the anti-abrin antibody treatment at late time points after exposure.  相似文献   
194.
The effect of aminophylline on renin release from human chorion was investigated by perfusing the tissue with various concentrations of the drug. Buffer containing aminophylline (2 X 10(-6) mol/l) doubled the rate of active and total renin secretion, but a more concentrated solution (10(-5) mol/l) released proportionately less active and total renin although the result was statistically significant. Renin secretion was not altered by aminophylline (5 X 10(-5) mol/l). The pattern of renin release was modulated by concentrations of aminophylline which were at least a 100-fold lower than those required to inhibit cyclic adenosine 3',5'-monophosphate phosphodiesterase. However, as the methylxanthines are potent adenosine receptor antagonists, we suggest that in the human chorion adenosine is a mediator of renin release.  相似文献   
195.
Differences in breastfeeding, other milk feeding and complementary feeding patterns were evaluated in infants at increased genetic risk with and without maternal type 1 diabetes (T1D). The Trial to Reduce IDDM in the Genetically at Risk is an international nutritional primary prevention double‐blinded randomized trial to test whether weaning to extensively hydrolyzed vs. intact cow's milk protein formula will decrease the development of T1D‐associated autoantibodies and T1D. Infant diet was prospectively assessed at two visits and seven telephone interviews between birth and 8 months. Countries were grouped into seven regions: Australia, Canada, Northern Europe, Southern Europe, Central Europe I, Central Europe II and the United States. Newborn infants with a first‐degree relative with T1D and increased human leukocyte antigen‐conferred susceptibility to T1D were recruited. A lower proportion of infants born to mothers with than without T1D were breastfed until 6 months of age in all regions (range, 51% to 60% vs. 70% to 80%). Complementary feeding patterns differed more by region than by maternal T1D. In Northern Europe, a higher proportion of infants consumed vegetables and fruits daily compared with other regions. Consumption of meat was more frequent in all European regions, whereas cereal consumption was most frequent in Southern Europe, Canada and the United States. Maternal T1D status was associated with breastfeeding and other milk feeding patterns similarly across regions but was unrelated to the introduction of complementary foods. Infant feeding patterns differed significantly among regions and were largely inconsistent with current recommended guidelines.  相似文献   
196.
Penetration of imipenem into human aqueous and vitreous humor   总被引:2,自引:0,他引:2  
Twenty-five patients about to undergo cataract surgery and ten patients about to undergo vitrectomy received a 1-g intravenous dose of imipenem before surgery. Specimens of aqueous or vitreous humor were then obtained and assayed for antibiotic content with a microbiologic disk agar technique. A mean peak aqueous humor level of 2.99 micrograms/ml was found at approximately two hours after administration, and a mean vitreous level of 2.53 micrograms/ml was found from two hours to three hours 15 minutes after administration. These concentrations were well above the minimum inhibitory concentration of imipenem for 90% (MIC90) of Staphylococcus epidermidis, S. aureus, and the Enterobacteriaceae commonly involved in bacterial endophthalmitis.  相似文献   
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199.
JUSTIFICATION: Acute rheumatic fever and rheumatic chronic valvular heart disease is an important preventable cause of morbidity and mortality in suburban and rural India. Its diagnosis is based on clinical criteria. These criteria need verification and revision in the Indian context. Furthermore, there are glaring differences in management protocols available in literature. These facts prompted Indian Academy of Pediatrics to review the management of rheumatic fever. PROCESS: Management of Rheumatic fever was reviewed and recommendation was formulated at national consultative meeting on 20th May 2007 at New Delhi. OBJECTIVES: To formulate uniform guidelines on management of acute rheumatic fever and rheumatic heart disease in the Indian context. Guidelines were formulated for the management of streptococcal pharyngitis, acute rheumatic fever and its cardiac complication as well as secondary prophylaxis for recurrent episodes. RECOMMENDATIONS: (1) Streptococcal eradication with appropriate antibiotics (Benzathine penicillin single dose or penicillin V oral or azithromycin). (2) Diagnosis of rheumatic fever based on Jones criteria. (3) Control inflammatory process with aspirin with or without steroids (total duration of treatment of 12 weeks). (4) Treatment of chorea according to severity (therapy to continue for 2-3 weeks after clinical improvement). (5) Protocol for managing cardiac complication like valvular heart disease, congestive heart failure and atrial fibrillation. (6) Secondary prophylaxis with benzathine penicillin and management of anaphylaxis.  相似文献   
200.
The aim of this article is to explore the reasons for seeking selected information on a food label, with particular emphasis on certain information about sugar. In order to meet the aim, in 2020, a survey was conducted among consumers aged 18–45. Predictive models (Logistic Regression) were developed for noticing “light” products and reading food labels. The results of our study indicate that consumers are mainly discouraged from reading label information by a large amount of information, the lack of time, and a general reluctance to be interested in label information. When it comes to the factors that lead people to read label information, the naturalness of the product, its organic origin, and physical activity are important. Moreover, respondents who declared that they noticed products on the market defined as “light” were those who were interested in the naturalness of the product, but also consumers declaring that they have nutritional knowledge. The results of the study indicate the need to intensify information campaigns in order to emphasize how important it is for consumers to read the information on food labels. The amount and complexity of information currently appearing on the food label may unfortunately discourage consumers from reading it, so it is important to continuously improve this form of communication with the consumer.  相似文献   
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