Effectiveness of the 2010-2011 seasonal influenza vaccine in preventing confirmed influenza hospitalizations in adults: a case-case comparison, case-control study.

INTRODUCTION: We estimated influenza vaccine effectiveness (IVE) to prevent laboratory-confirmed influenza-related hospitalizations in patients 18 years old or older during the 2010-2011 influenza season. METHODS: We conducted a prospective case-control study in five hospitals, in Valencia, Spain. Study subjects were consecutive emergency hospitalizations for predefined conditions associated with an influenza-like illness episode <8 days before admission. Patients were considered immunized if vaccinated ≥14 days before influenza-like illness onset. Cases were those with a real time reverse transcriptase polymerase chain reaction (RT-PCR) positive for influenza and controls were RT-PCR positive for other respiratory viruses. Adjusted IVE was estimated as 100×(1-adjusted odds ratio). To account for indication bias we computed adjusted IVE for respiratory syncytial virus related hospitalizations. RESULTS: Of 826 eligible hospitalized patients, 102 (12%) were influenza positive and considered cases, and 116 (14%) were positive for other respiratory viruses and considered controls. Adjusted IVE was 54% (95% confidence interval, 11-76%). By subgroup, adjusted IVE was 53% (4-77%) for those with high-risk conditions, 59% (16-79%) for those ≥60 years of age, and, 54% (4-79%) for those ≥60 years of age with high-risk conditions. No influenza vaccine effect was observed against respiratory syncytial virus related hospitalization. CONCLUSION: Influenza vaccination was associated with a significant reduction on the risk of confirmed influenza hospitalization, irrespective of age and high-risk conditions.

Aluminum-induced pro-oxidant effects in rats: protective role of exogenous melatonin.

In recent years, it has been suggested that oxidative stress is a feature of Alzheimer's disease in which aluminum (Al) could exacerbate oxidative events. The goal of the present study was to assess in rats the pro-oxidant effects induced by Al exposure, as well as the protective role of exogenous melatonin. Two groups of male rats were intraperitoneally injected with Al only or melatonin only, at doses of 5 and 10 mg/kg/day, respectively for 8 wk. During this period, a third group of animals received Al (5 mg/kg/day) and melatonin (10 mg/kg/day). At the end of the treatment period, rats were anesthesized and arterial blood was obtained. Thereafter, animals were killed and liver and brain (cortex, hippocampus and cerebellum) were removed. These tissues were processed to examine oxidative stress markers: glutathione transferase (GST), reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), catalase (CAT), thiobarbituric acid reactive substances (TBARS), as well as protein content. Samples of these tissues were also used to determine Al, Fe, Mn, Cu and Zn concentrations. The results show that Al exposure promotes oxidative stress in different neural areas, including those in which Al concentrations were not significantly increased. The biochemical changes observed in neural tissues show that Al acts as pro-oxidant, while melatonin exerts an antioxidant action in Al-treated animals. The protective effects of melatonin against cellular damage caused by Al-induced oxidative stress, together with its low toxicity, make melatonin worthy of investigation as a potential supplement to be included in the treatment of neurological disorders in which the oxidative effects must be minimized.

Age-Related differences on aluminium mobilization by chelating agents in aluminium-loaded uraemic rats.

The efficacy of deferoxamine, deferiprone, and a combination of these chelating agents in the mobilization and promotion of aluminium (Al) excretion was compared in two age groups of uraemic rats which had previously received Al nitrate nonahydrate intraperitoneally in a daily dose of 45 mg/kg for 5 weeks. At the end of the period of Al exposure, Al-loaded rats of each age (young and adult) group were given one of the following treatments for 5 days: 0.90 mmol/kg/ day of deferoxamine (subcutaneously), 0.90 mmol/kg/day of deferiprone (orally), and 0.45 mmol/kg/day of deferoxamine (subcutaneously) plus 0.45 mmol/kg/day of deferiprone (orally). Control rats were given 0.9% saline (subcutaneously) and deionized water (orally). Total urines were collected 24 hr after each chelator administration. Although young rats treated with deferoxamine, deferiprone, or deferoxamine plus deferiprone showed significant increases in the total amount of Al excreted into urine during 5 consecutive days, the effect of combined administration of deferoxamine and deferiprone was lower than that caused by deferoxamine or deferiprone only. On the other hand, after administration of deferoxamine and deferiprone, a significant reduction of Al was noted only in the liver of young rats, while no significant effects of the chelators were seen in any of the examined tissues of adult animals. The results of the current study show that a combined therapy with deferoxamine and deferiprone (at half-doses of each drug) can also be effective in mobilizing Al from the body of Al-loaded uraemic rats.

Chelation therapy in aluminum-loaded rats: influence of age.

The influence of age at which aluminum (Al) exposure was initiated on the efficacy of chelation therapy in mobilizing Al was investigated in two groups of male rats exposed to this element at two different stages of the life cycle. Young (21 days old) and old (18 months) rats were exposed to 0 and 50 mg Al/kg/day administered as Al nitrate in drinking water for a preliminary period of 14 days followed by a period of 100 days, in which Al-exposed animals received 100 mg Al/kg/day. At the end of the period of exposure, Al-loaded rats in each age group were given one of the following treatments: s.c. deferoxamine (DFO), oral 1,2-dimethyl-3-hydroxypyrid-4-one (L1) and 1-(p-methylbenzyl)-2-ethyl-3-hydroxypyrid-4-one (MeBzEM) at doses of 0.89 mmol/kg/day for 5 consecutive days. Another group of Al-exposed rats received a concurrent administration of s.c. DFO and oral L1 both at 0.45 mmol/kg/day. During chelation therapy urines were collected daily. Control groups included rats exposed and unexposed to Al. Oral administration of L1 was the most effective treatment in enhancing urinary Al excretion in both age groups of Al-loaded rats. This beneficial effect was similar for old and young animals. Concurrent administration of DFO and L1 had no advantages over the use of either single agent, while MeBzEM was not effective in mobilizing Al from Al-exposed rats.

Prenatal effects of caffeine and restraint stress in mice.

The maternal and developmental toxicity of combined exposure to restraint stress and caffeine was assessed in mice. On Day 9 of gestation, six groups of pregnant mice were treated (p.o.) with a single dose of 30, 60, or 120 mg/kg of caffeine. Immediately after caffeine administration, three of these groups were subjected to restraint for 14 hr. Control groups included unrestrained and restrained pregnant mice not exposed to caffeine. An additional group of animals (unrestrained and not exposed to caffeine) was deprived of food for 14 hr. A two-way (caffeine dose x restraint) analysis of variance revealed an overall effect (reduction) of restraint and caffeine exposure on maternal body weight gain and food consumption on gestation Days 9-11. Significant reductions were also observed in body weight at termination and corrected body weight change of dams concurrently exposed to 120 mg/kg of caffeine and restraint. By contrast, no significant effects of caffeine, restraint, or caffeine plus restraint on embryo/fetal development were noted. The doses of caffeine administered here are much higher than those usually consumed by the general population. Under the current experimental conditions, caffeine alone or combined with restraint stress was not embryotoxic or teratogenic in mice.

Comparative aluminum mobilizing actions of deferoxamine and four 3-hydroxypyrid-4-ones in aluminum-loaded rats.

The efficacy of the Al chelating drugs deferoxamine (DFO) and the hydoxypyridones (HPs): 1,2-dimethyl-3-hydroxypyrid-4-one (L1), 1-[3-hydroxy-2-methyl-4-oxopyridyl]-2-ethanesulfonic acid (L6), 1-benzyl-(4-carboxylic acid)-3-hydroxy-2-methyl-4-oxopyridine (Bzcal) and 1-(p-methylbenzyl)-2-ethyl-3-hydroxypyrid-4-one (MeBzEM) in increasing Al excretion and reducing tissue Al accumulation has been compared in adult male rats which had previously received Al nitrate nonahydrate i.p. at 0.16 mmol/kg per day for 2 months. At the end of this period, DFO was injected s.c. and the HPs were given by gavage at 0.89 mmol/kg per day for five consecutive days. Total urines were collected 24 h after each chelator administration. Following chelation treatment animals were killed and samples of brain, bone, liver, kidney, and spleen were collected. DFO administration increased to about 4 x the cumulative urinary Al elimination for 5 days, while the excretion of Al into urine caused by Bzcal, L1, and MeBzEM administration was about twice that of the control group. On the other hand, treatment with Bzcal, DFO, and MeBzEM for 5 days significantly reduced the Al levels in bone by 31, 33, and 29%, and the Al concentrations in brain by 46, 69, and 71%, respectively. These results suggest that oral administrations of MeBzEM and Bzcal can be potential alternatives to parenteral administration of DFO in Al removal.

The effect of maternal restraint on developmental toxicity of aluminum in mice.

Both aluminum (Al) and maternal restraint have been reported to cause developmental toxicity in mammals. This study assessed in pregnant mice the potential interaction between Al and maternal restraint. Four groups of plug-positive female mice were given IP injections of AlCl3 at 37.5 and 75 mg/kg/day on days 6-15 of gestation. Two of these groups were also subjected to restraint for 2 h/day during the same gestational days. Control groups included restrained and unrestrained pregnant mice nonexposed to Al. Cesarean sections were performed on gestation day 18, and the fetuses were weighed and examined for morphological defects. Maternal toxicity was significantly enhanced by restraint at 75 mg AlCl3/kg/day. No increases in the number of resorptions or dead fetuses per litter were observed following exposure to Al, maternal restraint, or combined Al and restraint. However, a significant decrease in fetal body weight, as well as a significant increase in the number of litters with morphologic defects, was observed in the group exposed to 75 mg AlCl3/kg/day plus maternal restraint. The current results suggest that maternal restraint could enhance the metal-induced developmental toxicity (reduced fetal body weight, increase in the number of litters with morphologic defects) only at high doses of the metal, which are also toxic to the dam.

Aluminium distribution and excretion: a comparative study of a number of chelating agents in rats.

The present study was conducted to assess in rats the comparative effects of a number of chelating agents on the urinary excretion and tissue distribution of A1. Adult male Sprague-Dawley rats received a single intraperitoneal dose of aluminium (A1) nitrate nonahydrate (0.24 mmol/kg). Ten min. after A1 injection 1,2-dimethyl-3-hydroxypyrid-4-one, 2,3-dihydroxybenzoic acid, picolinic acid, methylmalonic acid, ethylenediamine-di(o-hydroxyphenylacetic) acid, 1-benzyl-2-methyl-3-hydroxypyrid-4-one, 1-(p-methylbenzyl)-2-methyl-3-hydroxypyrid-4-one, 1-(p-methoxy-benzyl)-2-methyl-3-hydroxypyrid-4-one, 1-(p-chlorobenzyl)-2-methyl-3-hydroxypyrid-4-one, 1-benzyl-2-ethyl-3-hydroxypyrid-4-one, 1-(p-methyl-benzyl)-2-ethyl-3-hydroxypyrid-4-one, 1-[3-hydroxy-2-methyl-4-oxopyridyl]-2-ethanesulfonic acid and 1-benzyl-(4-carboxylic acid)-3-hydroxy-2-methyl-4-oxopyridine were given by gavage at 1.79 mmol/kg. A control group received similar volumes of distilled water. An additional group of rats received a subcutaneous injection of desferrioxamine at 1.79 mmol/ kg. Urine samples were collected daily for three consecutive days and the animals were killed after this period. Samples of brain, bone, liver, kidney and spleen were collected. Although desferrioxamine, 1,2-dimethyl-3-hydroxypirid-4-one, 1-(p-methylbenzyl)-2-methyl-3-hydroxypyrid-4-one, 1-(p-methoxybenzyl)-2-methyl-3- hydroxypyrid-4-one, 1-(p-methylbenzyl)-2-ethyl-3-hydroxypyrid-4-one, 1-[3-hydroxy-2-methyl-4-oxopyridyl]-2-ethanesulfonic acid and 1-benzyl-(4-carboxylic acid)-3-hydroxy-2-methyl-4-osopyridine significantly enhanced the total excretion of A1 into urine, only treatment with 1-(p-chlorobenzyl)-2-methyl-3-hydroxypyrid-4-one and 1-benzyl-2-ethyl-3-hydroxypyrid-4-one significantly reduced A1 concentrations in all analyzed tissues. No beneficial effects of the remaining chelators on Al mobilization were observed. Further studies on the effects of some 3-hydoxrypyrid-4-ones on A1 removal can be of interest for the treatment of A1 accumulation and toxicity.

[Eclectic surgery of gastroesophageal reflux-hiatal hernia]. / Cirugía ecléctica del reflujo gastro-esofágico-hernia hiatal.

We have reviewed 1,725 cases of RGE-HH, corresponding to the period between February 1967 to July 1989; the total number of clinical histories in that period of time was 17,553. Of this series, 1,594 (92.OFF were sliding hernias; 214 (12.4%) were operated. In order to prevent recurrences, in 146 cases (68.2%) of sliding hernia, which we expose in the present paper, we have employed different surgical techniques, associated to the pexia of the round ligament. Presently, the surgical technique of our preference is the anterior SemiNissen or Dor's hemivalve, with closure of the His' angle, the hiatus and the pillars of the diaphragm, when indicated, and pexia of the round ligament. There has not been mortality and the results have been excellent in 81.6% of the cases; good in 10.3%; fair in 4.5%, and poor or recurrence in 3.4%.