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51.
Antonella?RussoEmail author Rosalia?Pellitteri Rosa?Romeo Stefania?Stanzani André?Jean 《Behavioral and brain functions : BBF》2005,1(1):17
Different findings indicate that rostral ventrolateral reticular nucleus (RVL) is neuronal substrate of integration and regulation
of the cardiovascular functions. Some efferent RVL neurons project to the thoraco-lumbar spinal cord and excite preganglionic
sympathetic neurons, to the spinal phrenic motor neurons involved in inspiratory function and increase the activity of vasoconstrictor
fibres innervating blood vessels in the skin and skeletal muscle. Our study was aimed at revealing presence of neurons within
RVL supplying branching collateral input to the medial preoptic area (MPA) and to the lumbo-sacral spinal cord (SC-L) in the
rat. All animal experiments were carried out in accordance with current institutional guidelines for the care and use of experimental
animals. We have employed double fluorescent-labelling procedure: the projections were defined by injections of two retrograde
tracers: Rhodamine Labelled Bead (RBL) and Fluoro Gold (FG) in the MPA and SC-L, respectively. Our results showed the presence
of few single FG neurons and single RBL neurons in the RVL. The size of FG-neurons and RBL-neurons was medium (25–30 μm) and
large (50 μm). 相似文献
52.
Russo A Pellitteri R Monaco S Romeo R Stanzani S 《Brain research. Developmental brain research》2005,154(2):211-216
The neurotransmitter serotonin (5-HT) is involved in various physiological functions via multiple receptor subtypes. These have been classified in seven receptor families (5-HT1-7) on the basis of their structures and functional characteristics. In this study, we examined the expression of 5-HT7 receptors in the rat hypothalamic neurons cultured "in vitro" during postnatal development. Neuronal cultures were prepared from postnatal pups P2, P3 and P5, were treated with bFGF and processed by means of immunofluorescence technique using a polyclonal 5-HT7 receptor antibody. In P2, we found a low density of 5-HT7 labeled hypothalamic bFGF-treated neurons and no 5-HT7 immunolabeling in control cultures; in P3, a moderate number of bFGF-treated neurons were observed but they were not bright. No 5-HT7 immunolabeling was found in controls. In P5, a heavy labeling of small sized bipolar neurons was seen in bFGF-treated neurons, while in control cultures, few labeled neurons with a low stained density were observed. These results suggest that 5-HT7 receptors in hypothalamic neurons begin to appear at P5 and then could be involved in many physiological implications that are not exerted at P2 and P3. This indicates that 5-HT7 receptors have a potential significance in the rat hypothalamus during early postnatal development. 相似文献
53.
Obstruction of the upper urinary tract poses a significant clinical challenge to the urologist, and the cascade of renal cellular and molecular events triggered by upper urinary tract obstruction result in a progressive, and eventually permanent, loss in renal function. These pathological changes include the development of renal fibrosis, tubular atrophy, interstitial inflammation, and apoptotic renal cell death. A myriad of cytokines and growth factors have been identified as major contributors to obstruction-induced renal fibrosis and apoptotic cell death, including transforming growth factor-beta1, angiotensin II, nuclear factor-kappaB, and tumor necrosis factor-alpha. This review examines the role of these mediators in obstruction-induced renal injury. 相似文献
54.
Petrucca A Cipriani P Sessa R Teggi A Pustorino R Santapaola D Nicoletti M 《Emerging infectious diseases》2004,10(11):1957-1959
We report a case of a vaginal infection caused by a strain of Burkholderia cenocepacia. The strain was isolated from vaginal swab specimens from a 68-year-old woman with smoldering myeloma and chronic hepatitis C virus infection who was hospitalized for abdominal abscess. Treatment with piperacillin/tazobactam eliminated B. cenocepacia infection and vaginal symptoms. 相似文献
55.
Bugianesi R Salucci M Leonardi C Ferracane R Catasta G Azzini E Maiani G 《European journal of nutrition》2004,43(6):360-366
Summary
Background
Epidemiological data showed that tomato and tomato product (sauce, paste) consumption is associated with a protective effect against the development of some chronic-degenerative diseases. Tomato antioxidant bioactive molecules such as carotenoids and polyphenols could be responsible, at least in part, for the healthy effect observed. The bioavailability of these compounds is an essential requirement to sustain their in vivo role. While it is well known that many factors can influence the bioaccessibility of carotenoids from the food matrix, there is little information about the factors affecting phenolic compounds bioaccessibility.
Aim of the study
This investigation was carried out to evaluate the effect of domestic cooking on the bioavailability in humans of antioxidant molecules after the administration of a test meal containing cherry tomatoes.
Methods
A cross-over design was conducted. Subjects (3 females and 2 males) consumed experimental meals containing fresh and cooked cherry tomatoes. Blood collection was performed at different time intervals (0, 2, 4, 6, 8 and 24 h).
Results
Carotenoid and phenol plasma concentrations were measured. Plasma levels of lycopene and -carotene were not significantly different with respect to the baseline after ingestion of both the test meals, while plasma concentrations of naringenin and chlorogenic acid increased significantly with respect to the baseline (P<0.05) after administration of cooked cherry tomatoes, but not after administration of fresh cherry tomatoes.
Conclusions
The present study indicated that domestically cooked tomatoes significantly increase naringenin and chlorogenic acid plasma levels. Considering that both naringenin and chlorogenic acid are widely studied for their potential healthy properties, evidence of their bioavailability and of the factors influencing their bioaccessibility is an important tool to sustain the possibility that these polyphenols play a biological role in human physiology. 相似文献
56.
57.
Ferracane JL Ferracane LL Braga RR 《Journal of biomedical materials research. Part B, Applied biomaterials》2003,66(1):318-323
Additives that provide stress relief may be incorporated into dental composites to reduce contraction stress (CS). This study attempted to test the hypothesis that conventional fillers could be replaced by high-density polyethylene (HDPE) spheres in hybrid and nanofill composites to reduce CS, but with minimal effect on mechanical properties. Nanofill and hybrid composites were made from a Bis-GMA/TEGDMA resin having either all silica nanofiller or 75 wt.% strontium glass + 5 wt.% silica and replacing some of the nanofiller or the glass with 0%, 5% (hybrid only), 10% or 20 wt.% HDPE. The surface of the HDPE was either left untreated or had a reactive gas surface treatment (RGST). Contraction stress (CS) was monitored for 10 min in a tensilometer (n = 5) after light curing for 60 s at 390 mW/cm(2). Other specimens (n = 5) were light cured 40 s from two sides in a light-curing unit and aged 1 d in water before testing fracture toughness (K(Ic)), flexure strength (FS), and modulus (E). Results were analyzed by ANOVA with Tukey's multiple comparison test at p < 0.05. There was no difference between composites with RGST and untreated HDPE except for FS-10% HDPE hybrid (RGST higher). An increased level of HDPE reduced contraction stress for both types of composites. Flexure strength, modulus (hybrid only), and fracture toughness were also reduced as the concentration of HDPE increased. SEM showed evidence for HDPE debonding and plastic deformation during fracture of the hybrid composites. In conclusion, the addition of HDPE spheres reduces contraction stress in composites, either through stress relief or a reduction in elastic modulus. 相似文献
58.
Madhi SA Petersen K Khoosal M Huebner RE Mbelle N Mothupi R Saloojee H Crewe-Brown H Klugman KP 《The Pediatric infectious disease journal》2002,21(4):315-321
BACKGROUND: Haemophilus influenzae type b (Hib) conjugate vaccines have successfully reduced the burden of invasive Hib disease in developed countries; however, their effectiveness in countries with a high incidence of pediatric HIV-1 is unknown. METHODS: The effectiveness of Hib conjugate vaccine was prospectively evaluated in South African children. The burden of invasive Hib disease in children < 1 year old was compared in 2 cohorts. The first cohort included 22,000 African children born in 1997 [969 (4.45%) of whom were estimated to be HIV-1-infected] who were not vaccinated with Hib conjugate vaccine. This group was compared with 19,267 children [1162 (6.03%) of whom were estimated to be HIV-1 infected] vaccinated at 6, 10 and 14 weeks of age with an Hib conjugate vaccine [TETRAMUNE (polyribosylribitol phosphate-CRM(197)-diphtheria-tetanus toxoids-whole cell pertussis)] between March, 1998, and June, 1999. RESULTS: The estimated burden of invasive Hib disease in nonimmunized HIV-1-infected children < 1 year of age was 5.9-fold [95% confidence interval (95% CI), 2.7 to 12.6] higher than in HIV-1-uninfected children. The overall estimated effectiveness of Hib conjugate vaccine in fully vaccinated children <1 year of age was 83.2% (95% CI 60.3 to 92.9). Vaccine effectiveness was significantly reduced in HIV-1-infected [43.9% (95% CI -76.1 to 82.1)] compared with uninfected children [96.5% (95% CI 74.4 to 99.5); P < 10(-5)]. Among three of the fully vaccinated HIV-1-infected children who developed invasive Hib disease, the anti-Hib polyribosylribitol phosphate serum antibody concentrations were 0.23, 0.25 and 0.68 microg/ml. CONCLUSION: Although the Hib conjugate vaccine was less effective among HIV-1-infected than among uninfected children, it was 83% effective in preventing overall invasive Hib disease and therefore should be considered for inclusion in the routine vaccination schedule by other African countries. 相似文献
59.
Avallone B Porritiello M Esposito D Mutone R Balsamo G Marmo F 《Hearing research》2003,178(1-2):79-88
We studied hair cell regeneration in the crista ampullaris of the lizard Podarcis sicula both in untreated animals and at early and late time intervals following a single high dose of gentamicin. The study was carried out using the S-phase marker 5-bromo-2'-deoxyuridine. Our ultrastructural and immunofluorescence studies showed that both apoptosis and hair cell regeneration happen in the lizard crista ampullaris in untreated animals, and that regenerative processes are greatly accelerated after treatment with the aminoglycoside antibiotic gentamicin. Our observations indicate that hair cell regeneration is strongly implicated in the repair of damaged sensory epithelium, and that new hair cells appear likely to arise from supporting cells. 相似文献
60.
Rodriguez-Garcia R 《Journal of community health》2001,26(2):93-112
The process of globalization has rendered societies interdependent on one another and has fostered the movement of people, goods and ideas at unprecedented speed and volume. Global travel has grown from 25 million in 1950 to 500 million in 1993, and estimations by 2010 reach 1 billion. The increased intensity and quantity of travel has resulted in greater vulnerability to the domino-type spread of old, new and re-emerging infectious diseases. Travelers and local populations are also vulnerable to death and disability due to accidents, violence and injuries, chronic diseases such as those due to substance abuse (tobacco, alcohol and others), and to undesirable behaviors such as those related to sex-tourism. This article argues that tourism, understood as any type of travel, is one of the most important sectors of the economy in many countries and, therefore, can contribute to community and national development. It also asserts that travel, as a factor in the spread of disease, lies in the realm of public health inquiry. It calls for greater collaboration between the tourism-travel industry and community, national and global leaders to promote and enforce responsible tourism. 相似文献