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排序方式: 共有9596条查询结果,搜索用时 23 毫秒
71.
72.
Michaël Chopin Aaron T. Lun Yifan Zhan Jaring Schreuder Hannah Coughlan Angela D’Amico Lisa A. Mielke Francisca F. Almeida Andrew J. Kueh Ross A. Dickins Gabrielle T. Belz Shalin H. Naik Andrew M. Lew Phillipe Bouillet Marco J. Herold Gordon K. Smyth Lynn M. Corcoran Stephen L. Nutt 《Immunity》2019,50(1):77-90.e5
73.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
74.
Reciprocal effect of Waardenburg syndrome mutations on DNA binding by the Pax-3 paired domain and homeodomain 总被引:1,自引:1,他引:1
The Pax-3 protein contains two DNA-binding domains, a paired domain and a
homeodomain. Mutations in Pax-3 cause Waardenburg syndrome (WS) in humans
and the mouse Splotch (Sp) phenotype. In the Sp-delayed mouse, a mutation
in the Pax-3 paired domain (G9R) abrogates the DNA-binding activity of both
the paired domain and the homeodomain, suggesting that they may
functionally interact. To investigate this possibility further, we have
analyzed the DNA-binding properties of additional point mutants in the
Pax-3 paired domain and homeodomain that occur in WS patients (F12L, N14H,
G15S, P17L, R23L, G48A, S51F and G66D in the paired domain, V47F and R53G
in the homeodomain), the Pax-1 un mutation (G15A) and a substitution
associated with Peters' anomaly in the PAX-6 gene (R23G). Within the paired
domain, seven of 10 mutations were found to abrogate DNA-binding by the
paired domain. Remarkably, these seven mutations also affected DNA binding
by the homeodomain, causing either a complete loss (P17L and G66D), a
reduction (R23G, R23L, G15S and G15A) or an increase in DNA-binding
activity (N14H). In addition, the effect of paired domain mutations
occurred at the level of monomer formation by the homeodomain, while the
dimerization potential of this domain seemed unaffected in mutants where it
could be analyzed. Furthermore, while both homeodomain mutations were found
to abolish DNA binding by this domain, the R53G mutation also abrogated DNA
binding by the paired domain. The important observation that independent
mutations in either domain can affect DNA binding by the other in the
intact Pax- 3 protein strongly suggests that the two domains are not
functionally independent but bind DNA through cooperative interactions.
Modeling the deleterlous mutations on the three-dimensional structure of
the paired domain of Drosophila Prd shows that these mutations cluster at
the DNA interface, thus suggesting that a series of DNA contacts are
essential for DNA binding by both the paired domain and the homeodomain of
Pax-3.
相似文献
75.
Maria do Carmo Debur Juliano Bordignon Claudia Nunes Duarte dos Santos Luine Rosele Vidal Meri Bordignon Nogueira Sérgio Monteiro de Almeida Sonia Mara Raboni 《Journal of clinical virology》2007,39(1):59-62
BACKGROUND: Human metapneumovirus (hMPV) has been described as an etiologic agent of acute respiratory infections (ARI), mainly in pediatric patients. Viral isolation is difficult and has low sensitivity, and consequently RT-PCR assays are currently used for detection. OBJECTIVES: Detect hMPV in ARI in hospitalized children in Southern Brazil; standardize a RT-PCR for routine hMPV diagnosis; validate a positive control for molecular tests; and perform phylogenetics analyses. STUDY DESIGN: Nasopharyngeal aspirates (NPA) from 156 hospitalized children were studied. A conserved region of the nucleoprotein gene was cloned, characterized and used to standardize an RT-PCR assay. Phylogenetic analyses were performed. Clinical data were obtained from medical records. RESULTS: hMPV was detected in 6.4% of the samples. Dyspnea and wheezing were frequently reported symptoms and the most common diagnoses were bronchiolitis, acute respiratory insufficiency or laryngotracheobronchitis. Nucleotide sequence alignment revealed 97.7% identity with genotype A1 of hMPV. The detection limit of hMPV genomes by RT-PCR in clinical samples was 180 copies/microL. CONCLUSION: This is the first report of the detection and genetic characterization of hMPV infections in children with lower ARI in Southern Brazil. 相似文献
76.
The effects of postnatal protein malnutrition on juvenile social behaviors were investigated in male and female Wistar rats. During the lactation period (21 days), each litter (six male and two female pups) was provided with 16% (control) or 6% (low protein) casein diets. At weaning, the control group (W) continued to receive the 16% protein diet and the malnourished group was divided into two groups: one continuing to receive a 6% protein diet (malnourished group - M) and the other shifted to a 16% protein diet (previously malnourished group - PM). These conditions lasted until 38 days of age when the behavioral tests ended. To assess social interaction, pairs of rats of the same nutritional condition and same gender were placed in a familiar arena for 3 consecutive days. Playful social behavior (pin), nonplayful social behavior (anogenital sniff, walk-over, side-mount and allogroom) and nonsocial behavior (rear) were recorded in three 10-min sessions. Postnatal protein malnutrition significantly decreased playful social behavior, nonsocial behavior (rear) and nonplayful social behaviors such as side-mount and walk-over. Anogenital sniff and allogroom were increased by early malnutrition. Nutritional rehabilitation from weaning reversed the changes produced by protein malnutrition in nonplayful (side-mount, walk-over, anogenital sniff and allogroom) and nonsocial behaviors (rear) but increased playful social behavior (pin). Gender effects were observed only on side-mount (higher incidence in males) and walk-over (higher incidence in females) indicating that playful behavior and nonsocial behavior were not affected by sex. The present results suggest that behavioral differences described in adulthood may result from changes in social behaviors of juvenile rats induced by early protein malnutrition. 相似文献
77.
A model of chronic pain in the rat: functional correlates of alterations in the activity of opioid systems 总被引:8,自引:0,他引:8
M J Millan A Cz?onkowski C W Pilcher O F Almeida M H Millan F C Colpaert A Herz 《The Journal of neuroscience》1987,7(1):77-87
Intradermal inoculation of rats at the tail base with Mycobacterium butyricum led to the gradual development of an arthritic swelling of the limbs which peaked at 3 weeks and subsided thereafter. Arthritic rats displayed a loss of body weight, hypophagia, and hypodipsia in addition to a disruption of the diurnal rhythms of ingestive behavior and of core temperature. The activity of adenohypophyseal beta-endorphin-(beta-EP) secreting corticotrophs, in contrast to prolactin-(PRL) secreting lactotrophs, was increased in arthritic rats. Indeed, hypertrophy of the adrenal glands was seen. Arthritic rats also showed an elevation in spinal cord levels of immunoreactive dynorphin (DYN), an endogenous ligand of the kappa-opioid receptor. The paws and tail of arthritic rats showed lower thresholds in response to noxious pressure (hyperalgesia), higher thresholds in response to noxious heat (hypoalgesia), and no change in their response to noxious electrical stimulation. Neither naloxone nor ICI-154, 129 (a preferential delta-receptor antagonist) modified the responses of the paw or tail to pressure. However, MR 2266 (an antagonist with higher activity at kappa-receptors) decreased thresholds to pressure in arthritic, but not control, rats; that is, it potentiated the hyperalgesia. This action was stereospecific. None of the antagonists modified the response to heat. MR 2266 did not affect the response to pressure in rats with acute inflammation produced by yeast. Thus, the potentiation of pressure hyperalgesia by MR 2266 in chronic arthritic rats is highly selective. Arthritic rats showed a reduced response to the analgesic effect of a kappa-agonist (U-50,488H), whereas the response to a mu-agonist (morphine) was enhanced. These effects were specific to nociception in that their influence upon endocrine secretion (PRL and beta-EP) was otherwise changed. The secretion of beta-EP and PRL was stimulated by both morphine and U-50,488H, and the influence of U-50,488H upon the release of beta-EP (from the adenohypophysis) was enhanced in arthritic rats. It is suggested that polyarthritis is a complex condition entailing many changes, both behavioral and endocrinological. Further, arthritic rats cannot simply be described as "hyperalgesic": of critical importance is the nature of the nociceptive stimulus applied. The parallel alterations in spinal cord pools of DYN and kappa-receptors (see also Millan et al., 1986) and the changes in the influence on nociception of kappa-agonists and kappa-antagonists suggest an increased activity of spinal DYN. Thus, spinal kappa-receptors may play a role in the modulation of nociception under chronic pain.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
78.
Belanoff Candice Alade Mayowa Oluwatosin Almeida Joanna 《Maternal and child health journal》2022,26(4):834-844
Maternal and Child Health Journal - Foreign-born non-Hispanic Black (NHB) birthing parents are less likely to have a preterm birth (PTB) than US-born NHBs. There is further variation by region and... 相似文献
79.
Maria Peres Manuela F. Almeida lia J. Pinto Carla Carmona Sara Rocha Arlindo Guimas Rosa Ribeiro Esmeralda Martins Anabela Bandeira Anita MacDonald Júlio C. Rocha 《Nutrients》2021,13(3)
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
80.
Gislene R. Amirato Juliana O. Borges Daniella L. Marques Juliana M. B. Santos Carlos A. F. Santos Marilia S. Andrade Guilherme E. Furtado Marcelo Rossi Lais N. Luis Raquel F. Zambonatto Eliane B. da Silva Sarah O. Poma Mariana M. de Almeida Renato L. Pelaquim Laiane C. dos Santos-Oliveira Vinicius L. Sousa Diniz Maria E. P. Passos Adriana C. Levada-Pires Renata Gorjo Marcelo P. Barros Andr L. L. Bachi Tania C. Pithon-Curi 《Nutrients》2021,13(3)
We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women. 相似文献