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41.
Horwitz MJ Tedesco MB Sereika SM Hollis BW Garcia-Ocaña A Stewart AF 《The Journal of clinical endocrinology and metabolism》2003,88(4):1603-1609
PTH and PTH-related protein (PTHrP) cause primary hyperparathyroidism and humoral hypercalcemia of malignancy (HHM), respectively. These syndromes are similar in several important ways, but differ in several characteristic, yet unexplained, ways. Two of the unresolved questions in HHM and hyperparathyroidism involve renal physiology. 1) Why does renal proximal tubular production of 1,25-dihydroxyvitamin D [1,25-(OH)(2)D] differ between the two syndromes? 2) Do distal tubular calcium responses to PTH and PTHrP differ in the two syndromes? To address these questions, we compared the two peptides, human PTH-(1-34) and PTHrP-(1-36), in a direct, head to head study using a continuous, steady state infusion of each peptide at the same dose in normal human volunteers for 46 h. We had previously described such methods as applied to PTHrP, but a direct multiday comparison of PTHrP to PTH has not previously been reported. In two groups (seven subjects each) of healthy young (25- to 35-yr-old) normal volunteers, PTH and PTHrP infused at 8 pmol/kg.h displayed similar calcemic effects, although PTH was slightly more potent in this regard. Both peptides also displayed similar phosphaturic effects. In addition, both peptides had similar effects on renal tubular calcium handling, yielding fractional calcium excretion values of approximately 3.5%, some 50% below the values (6.5%) observed in subjects rendered similarly hypercalcemic by the infusion of calcium. In contrast to these several quantitatively similar effects of PTH and PTHrP, PTH tended to be selectively more effective than PTHrP in stimulating renal production of 1,25-(OH)(2)D. These studies indicate that renal tubular calcium reabsorption is likely to contribute to hypercalcemia in patients with HHM. In addition, PTH may be selectively more effective than PTHrP in stimulating 1,25-(OH)(2)D production, in contrast to its phosphaturic, calcemic effects and its effects to stimulate nephrogenous cAMP excretion and renal tubular calcium reabsorption. 相似文献
42.
Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice 下载免费PDF全文
Robson Seriani Mara de Souza Junqueira Alessandra Choqueta de Toledo Milton Arruda Martins Marcelo Seckler Adriano Mesquita Alencar Elnara Marcia Negri Luiz Fernando Ferraz Silva Thaís Mauad Paulo Hilário Nascimento Saldiva Mariangela Macchione 《Environmental toxicology》2015,30(11):1297-1308
Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB+), neutral (PAS+), or mixed (AB/PAS+) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015. 相似文献
43.
Jones Brian E. Allegretti Andrew S. Pose Elisa Mara Kristin C. Ufere Nneka N. Avitabile Emma Shah Vijay H. Kamath Patrick S. Gins Pere Simonetto Douglas A. 《Digestive diseases and sciences》2022,67(2):697-707
Digestive Diseases and Sciences - Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy... 相似文献
44.
Effects of CCR5-Delta32 and CCR2-64I alleles on HIV-1 disease progression: the protection varies with duration of infection 总被引:5,自引:0,他引:5
Mulherin SA O'Brien TR Ioannidis JP Goedert JJ Buchbinder SP Coutinho RA Jamieson BD Meyer L Michael NL Pantaleo G Rizzardi GP Schuitemaker H Sheppard HW Theodorou ID Vlahov D Rosenberg PS;International Meta-Analysis of HIV Host Genetics 《AIDS (London, England)》2003,17(3):377-387
OBJECTIVE: To examine temporal variation in the effects of CCR5-Delta32 and CCR2-64I chemokine receptor gene polymorphisms on HIV-1 disease progression. DESIGN: Pooled analysis of individual patient data from 10 cohorts of HIV-1 seroconverters from the United States, Europe, and Australia. METHODS: We studied HIV-1 seroconverters of European (n = 1635) or African (n = 215) ancestry who had been genotyped for CCR5-Delta32 and CCR2-64I. We used Cox proportional hazards models with time-varying coefficients to determine whether the genetic protection against AIDS (1987 case definition) and death varied with time since seroconversion. RESULTS: Protection against AIDS conferred by CCR5-Delta32 held constant at a 31% (RH 0.69, 95% CI 0.54, 0.88) reduction in risk over the course of HIV-1 infection, whereas protection against death held constant at a 39% reduction in risk (RH 0.61, 95% CI 0.45, 0.88). When the period from AIDS to death was isolated, the survival benefit of CCR5-Delta32 diminished 2 years after AIDS. Protection against AIDS conferred by CCR2-64I was greatest early in the disease course. Compared with individuals without CCR5-Delta32 or CCR2-64I, individuals with one or two copies of CCR2-64I had a 58% lower risk of AIDS during the first 4 years after seroconversion (RH 0.42, 95% CI 0.23, 0.76), a 19% lower risk during the subsequent 4 years (RH 0.81, 95% CI 0.59, 1.12), and no significant protection thereafter. CONCLUSION: The protection against AIDS provided by CCR5-Delta32 is continuous during the course of infection. In contrast, the protection provided by CCR2-64I is greatest early in the course of infection. 相似文献
45.
Borrelia burgdorferi sensu lato (sl), the agent of Lyme disease, is transmitted to the host during the blood meal of Ixodes ticks. In most unfed ticks, spirochetes are present in the midgut and migrate during blood feeding to the salivary glands, from which they are transmitted to the host via saliva. In the present study, the efficiency of Ixodes ricinus ticks to transmit B. afzelii and B. burgdorferi sensu stricto (ss) and their infectivity for mice were examined in relation to the duration of the blood meal. In addition, we investigated whether these two Borrelia species can penetrate intact skin. Three modes of infection of mice were studied: tick-bite infection, inoculation of tick homogenates, and transcutaneous infection by topical application of tick homogenates on mouse skin. Transmission of B. burgdorferi sl from I. ricinus nymphs to mouse increased with duration of tick attachment. B. afzelii-infected ticks start to transmit infection earlier (< or = 48 h) than B. burgdorferi ss-infected ticks. As previously shown for B. burgdorferi ss in Ixodes scapularis, B. burgdorferi ss and B. afzelii in unfed I. ricinus were noninfectious for mice when tick homogenates were inoculated. However, the inoculation of homogenates of ticks fed for 24 h readily produced infection in mice. Therefore, B. burgdorferi ss and B. afzelii spirochetes are potentially infectious in the tick before natural transmission can occur. None of the mice (n = 33) became infected by transcutaneous transmission when tick homogenates were applied on mouse skin, showing that B. burgdorferi ss and B. afzelii are unable to penetrate intact skin, in contrast to relapsing fever spirochetes. This study also shows that B. afzelii is transmitted by I. ricinus to the host earlier than B. burgdorferi ss and that I. ricinus seems to be a more efficient vector of B. afzelii than B. burgdorferi ss. 相似文献
46.
Valdecira Rodrigues de Jesus Pricila Mara Novais de Oliveira Vivian Mara Gonçalves de Oliveira Azevedo 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):304-309
Background
The hammock positioning within the incubators simulates the intrauterine environment, however, there is little evidence of its benefits and possible risks.Objectives
The aim of this study was to assess the effects of hammock positioning on behavioral status, vital signs, and pain in very low birth weight preterm newborns.Methods
This is a quasi-experimental/case series study in which premature infants (<1500 g) were positioned in supine for one hour in a hammock. The preterm newborns were assessed 10 min before, during (2, 20, 40, and 60 min), and 10 min after hammock positioning with the Brazelton Neonatal Behavioral Assessment Scale, vital signs and pain by the Neonatal Facial Coding System.Results
28 preterm infants between 28 and 36 weeks of gestational age were evaluated. Regarding the behavioral state, the preterm newborns progressively evolved to light or deep sleep during hammock positioning. There was a statistically significant reduction of the heart and respiratory rate from 2 to 60th minute in a hammock, which was maintained after the positioning. The oxygen saturation remained within normal values. No changes in pain scores were observed.Conclusion
The hammock positioning can be considered a safe method of positioning that can be used to reduce the stress levels in very low birth weight preterm newborns. We did not observe worsening in either pain or vital signs. 相似文献47.
Simone Mara de Araújo Ferreira Thais de Oliveira Gozzo Marislei Sanches Panobianco Manoel Ant?nio dos Santos Ana Maria de Almeida 《Revista latino-americana de enfermagem》2015,23(1):82-89
AIM:
qualitative study, which aimed to identify the barriers that influence nursing care practices related to the sexuality of women with gynecological and breast cancer.METHODS:
the study was conducted with 16 professionals of the nursing area (nurses, nursing technicians and nursing assistants) from two sectors of a university hospital situated in the state of São Paulo, Brazil. The data was collected using semi-structured, in-depth individual interviews. All the interviews were recorded and the participants'' responses were identified and categorized using Content Analysis.RESULTS:
three major themes were identified. These are as follows: 1) barriers related to the biomedical model; 2) barriers related to institutional dynamics and 3) barriers related to the social interpretations of sexuality.CONCLUSIONS:
the results of this study showed that the systematized inclusion of this issue in nursing care routines requires changes in the health paradigm and in the work dynamic, as well as reflection on the personal values and social interpretations related to the topic. A major challenge is to divest sexuality of the taboos and prejudices which accompany it, as well as to contribute to the nursing team being more aware of the difficulties faced by women with gynaecological and breast cancer. 相似文献48.
Elena Makovac Sarah N Garfinkel Andrea Bassi Barbara Basile Emiliano Macaluso Mara Cercignani Giovanni Calcagnini Eugenio Mattei Daniela Agalliu Pietro Cortelli Carlo Caltagirone Marco Bozzali Hugo Critchley 《Neuropsychopharmacology》2015,40(7):1649-1658
Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets. 相似文献
49.
50.
Spielberg F Critchlow C Vittinghoff E Coletti AS Sheppard H Mayer KH Metzgerg D Judson FN Buchbinder S Chesney M Gross M 《AIDS (London, England)》2000,14(12):1819-1828
OBJECTIVE: To assess the feasibility and acceptability of bimonthly home oral fluid (OF) and dried blood spot (DBS) collection for HIV testing among high-risk individuals. DESIGN: A total of 241 participants [including men who have sex with men (MSM), injecting drug users (IDU), and women at heterosexual risk] were recruited from a randomly selected subset of study participants enrolled at four sites in the HIV Network for Prevention Trials (HIVNET) cohort, and assigned at random to bimonthly home collection of OF or DBS specimens over a 6 month interval. Participants could select telephone calls or clinic visits to receive HIV test results. METHODS: Bimonthly specimens were tracked for adherence to the schedule, were evaluated for adequacy for testing, and tested using antibody assays and polymerase chain reaction (PCR) for DBS. The acceptability of bimonthly home OF and DBS collection and telephone counseling was assessed in an end-of-study questionnaire. RESULTS: The laboratory received 96 and 90% of expected OF and DBS specimens, respectively; 99% of each specimen type was adequate for testing. Almost all (95%) participants chose results disclosure by telephone. The majority of participants (85%) reported that bimonthly testing did not make them worry more about HIV, and almost all (98%) judged that with bimonthly testing their risk behavior remained the same (77%) or became less risky (21%). CONCLUSION: Bimonthly home specimen collection of both OF and DBS with telephone counseling is acceptable and feasible among study participants at high risk. These methods will be useful for the early detection of HIV infection and remote follow-up of research cohort participants in HIV vaccine and prevention trials. 相似文献