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41.
OBJECTIVES: We correlated virologic and immunologic parameters of disease progression with cytopathogenicity of HIV isolates. STUDY DESIGN/METHODS: Human immunodeficiency virus type 1 (HIV-1) isolates from 207 patients with CD4+ cell counts < 500/mm3 were examined for biologic phenotype in MT-2 cells. We used a cross-sectional study design. RESULTS: Three subtypes of syncytium-inducing (SI) strains with different times of appearance of syncytia formation in cell culture and two subtypes of non-syncytium-inducing (NSI) isolates, with (NSI/MT2+) or without (NSI/MT2-) replicative capacity in MT-2 cells, were identified. Early SI strains were associated with the lowest CD4+ cell counts and the highest levels of viral load, and NSI/MT2- isolates correlated with the highest CD4+ cell counts and the lowest viral loads. Patients with late SI and NSI/MT2+ strains showed minimal differences in immunologic and virologic markers. CONCLUSIONS: Five HIV phenotypic variants that correlate significantly (P < 0.001) with markers of disease progression were identified.  相似文献   
42.
The amino acid sequence of the "double-headed" trypsin and chymotrypsin inhibitor (BTCI), purified from the cowpea Vigna unguiculata (L.) Walp. cv "Seridó" was determined in our laboratory. Tryptic and chymotryptic peptides were sequenced by the Edman-Gray and Edman-Chang N-terminal manual method as well as the carboxypeptidase C-terminal method. The complete amino acid sequence of the BTCI is: Ser-Gly-His-His-Glx-Asx-Ser-Thr-Asx-Glx-Ala-Ser-Glx-Ser-Ser-Lys-Pro-Cys- Cys-Arg- Glx-Cys-Ala-Cys-Thr-Lys-Ser-Ile-Pro-Pro-Glx-Cys-Arg-Cys-Ser-Asx-Val-Arg- Leu-Asn- Ser-Cys-His-Ser-Ala-Cys-Lys-Ser-Cys-Ala-Cys-Thr-Phe-Ser-Ile-Pro-Ala-Glx- Cys-Phe- Cys-Gly-Asx-Ile-Asx-Asx-Phe-Cys-Tyr-Lys-Pro-Cys-Lys-Ser-Ser-His-Ser-Asx- Asx-Asx-Asx-Trp-Asn. BTCI presents a high degree of homology with the Bowman-Birk proteinase inhibitor family.  相似文献   
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We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment.  相似文献   
45.
Although there is a large body of research connecting emotion to eating behaviors, little is known about the role of caregivers’ responses to children’s emotions in the context of child feeding. The purpose of this study was to analyze the relation between caregivers’ emotional responsiveness and feeding responsiveness. The mothers of 137 children between 2 and 6 years of age reported on their responses to children’s negative emotions using the Coping with Children’s Negative Emotions Scale and on their feeding practices using the Comprehensive Feeding Practices Questionnaire. The results showed that mothers’ supportive emotion responses (e.g., problem-focused, emotion-focused, and expressive encouragement reactions) tend to be positively associated with responsive feeding practices (e.g., encouraging, modelling, and teaching healthy food-related behaviors). Instead, mothers’ unsupportive responses (e.g., distress, punitive and minimization reactions) tend to be positively associated with nonresponsive feeding practices (e.g., food as reward or to regulate emotions, and pressure to eat) and negatively associated with responsive feeding practices. Our results suggest that emotional and feeding responsiveness may be intertwined and that differences in parent’s emotional responsiveness may translate into differences in their feeding styles, setting the stage for parents’ use of positive vs. negative feeding practices.  相似文献   
46.
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée.  相似文献   
47.
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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49.
Summary Capsaicin-sensitive sensory neurons of the rabbit iris, by releasing tachykinins, exert a major role in the control of pupil motility in response to various noxious stimuli. However, the contribution of sensory innervation to the regulation of iris smooth muscle tone in other mammals species is not known. We have studied the effects produced by electrical field stimulation, capsaicin, substance P, neurokinin A, calcitonin gene-related peptide (CGRP), and bradykinin in the isolated iris sphincter muscle of the pig.Capsaicin (10 M): a) contracted the isolated sphincter muscle and; b) released immunoreactivity for substance P (SP-LI) and CGRP (CGRP-LI) from this preparation. These two effects were no longer observed at the second exposure to the drug. Electrical field stimulation (10 Hz, 60 V, 0.5 ms for 5 s) produced a biphasic contractile response. The rapid component was inhibited by atropine (1 M), while the delayed response was blocked by previous exposure to capsaicin (10 M).Substance P and neurokinin A consistently produced contraction of the pig iris sphincter muscle, substance P being more potent than neurokinin A. CGRP induced a contractile response in more than 50% of the preparations. The tachykinin antagonist [D-Argl, D-Trp7,9, Leu11-substance P (3 M) blocked: a) the effect of substance P (1 nM); b) the delayed response to electrical field stimulation and; c) reduced by more than 50% response to capsaicin. Bradykinin (10 M) failed to release either SP-LI or CGRP-LI. The contractile response evoked by bradykinin was unaffected by in vitro pretreatment with capsaicin (10 M).The existence in the pig iris of capsaicin-sensitive sensory fibres releasing neuropeptides and thus regulating sphincter muscle tone is proposed. Send offprint requests to Dr. P. Geppetti at the above address  相似文献   
50.
In the present study we attempted a comprehensive characterization of modulation of noradrenaline release from chick sympathetic neurons. To this purpose sympathetic neurons derived from chick lumbosacral paravertebral ganglia and kept in culture for 7 days were loaded with 0.05 mol/l [3H]-noradrenaline and subjected to electrical field stimulation (36 pulses/3 Hz). Since the released transmitter was partially recaptured, superfusion was usually performed in the presence of (+)-oxaprotiline, an inhibitor of noradrenaline re-uptake. [3H]-Noradrenaline was released in a manner which was dependent on extracellular Ca2+ and sensitive to tetrodotoxin (TTX). -Conotoxin (-CTX; 100 nmol/l) abolished [3H]-noradrenaline release indicating that influx through -CTX-sensitive Ca2+-channels was essential for transmitter release. 1,4-dihydro-2,6-dimethyl-5-nitro4-[2-(trifluoromethyl)-phenyl]-3-pyridine carboxylic acid methyl ester ((±)Bay K 8644) and 4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3-nitro-5-pyridinecarboxylic acid isopropyl ester ((±)-202-791), agonists at L-type voltage sensitive Ca2+-channels (VSCCs), increased noradrenaline release and induced, in addition, an overflow of tritium which was Ca2+-dependent and prevented by the presence of TTX. The L-type VSCC antagonists (–)-202-791 and (+)-4-(4-benzofurazanyl)-1,4-dihydro2,6-dimethyl-3,5-pyridinedicar boxylic acid methyl, isopropyl ester ((+)-PN 200–110) diminished [3H]-noradrenaline release. These data suggest that L-type VSCCs, probably located on the cell body of the neuron, play an additional role in modulation of release. The full 2-adrenoceptor agonists 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline ( UK-14,304) and noradrenaline significantly inhibited noradrenaline release, whereas clonidine, a partial a2-agonist, produced only a slight inhibition even at 10 mol/l. The facilitation of noradrenaline release observed in the presence of the 2-adrenoceptor antagonist rauwolscine was very low in comparison to that obtained with brain slices and isolated smooth muscle tissues. These results corroborate the observation that noradrenaline release from chick sympathetic neurons is regulated by an 2-adrenoceptor which needs further subtype characterization. The experiments were mostly performed at 25°C, since a rise in temperature to 37°C increased the resting outflow, but not the evoked overflow of tritium, approximately 4-fold. In the presence of pargyline to block monoamine oxidase, however, the temperature-dependent enhancement was diminshed and the release showed properties comparable to those observed at 25°C (with respect to TTX-sensitivity, Ca2+ dependence and modulation via 2-adrenoceptors). In addition to the 2-adrenoceptors, we detected inhibitory -adrenoceptors, opioid and receptors, and P2 purinoceptors as well as facilitatory prostaglandin (PG) E receptors. No indication was found for a functional relevance of 5-hydroxytryptamine (5-HT), opioid , PGD, adenosine A1 or glutamate receptors. In conclusion, electrically evoked noradrenaline release from cultured chick sympathetic neurons shows the properties of action-potential-induced transmitter release and is bidirectionally regulated by various substances. Therefore, sympathetic neurons in culture offer the possibility to investigate directly the mechanisms bringing about receptor-coupled modulation of transmitter release.Abbreviations ATP adenosine 5-triphosphate - Bay K 8644 1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)-phenyl]-3-pyridine carboxylic acid methyl ester - DAGO (d-Ala2,N-methyl-Phe4,Gly-ol5)-enkephalin - DPDPE (d-Pen 2,5)-enkephalin - 5-HT 5-hydroxytryptamine - -CTX -conotoxin - KRBB modified Krebs-Ringer bicarbonate buffer - NMDA N-methyl-d-aspartic acid - PG prostaglandin - PN 200-110 4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxy lic acid methyl, isopropyl ester - R-PIA R(–)-N6-(2-phenyl-isopropyl)-adenosine - TTX tetrodotoxin - U-50,488H trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzene acetamide - UK-14,304 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline - VSCC voltage sensitive Ca2+-channel - 202-791 4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3-nitro-5-pyridinecarboxylic acid isopropyl ester Correspondence to: C. Allgaier at the above address  相似文献   
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