Microbial communities associated with electrodes harvesting electricity from a variety of aquatic sediments.

The microbial communities associated with electrodes from underwater fuel cells harvesting electricity from five different aquatic sediments were investigated. Three fuel cells were constructed with marine, salt-marsh, or freshwater sediments incubated in the laboratory. Fuel cells were also deployed in the field in salt marsh sediments in New Jersey and estuarine sediments in Oregon, USA. All of the sediments produced comparable amounts of power. Analysis of 16S rRNA gene sequences after 3-7 months of incubation demonstrated that all of the energy-harvesting anodes were highly enriched in microorganisms in the delta-Proteobacteria when compared with control electrodes not connected to a cathode. Geobacteraceae accounted for the majority of delta-Proteobacterial sequences or all of the energy-harvesting anodes, except the one deployed at the Oregon estuarine site. Quantitative PCR analysis of 16S rRNA genes and culturing studies indicated that Geobacteraceae were 100-fold more abundant on the marine-deployed anodes versus controls. Sequences most similar to microorganisms in the family Desulfobulbaceae predominated on the anode deployed in the estuarine sediments, and a significant proportion of the sequences recovered from the freshwater anodes were closely related to the Fe(III)-reducing isolate, Geothrix fermentans. There was also a specific enrichment of microorganisms on energy harvesting cathodes, but the enriched populations varied with the sediment/water source. Thus, future studies designed to help optimize the harvesting of electricity from aquatic sediments or waste organic matter should focus on the electrode interactions of these microorganisms which are most competitive in colonizing anodes and cathodes.

Harvesting energy from the marine sediment--water interface.

Pairs of platinum mesh or graphite fiber-based electrodes, one embedded in marine sediment (anode), the other in proximal seawater (cathode), have been used to harvest low-level power from natural, microbe established, voltage gradients at marine sediment-seawater interfaces in laboratory aquaria. The sustained power harvested thus far has been on the order of 0.01 W/m2 of electrode geometric area but is dependent on electrode design, sediment composition, and temperature. It is proposed that the sediment/anode-seawater/cathode configuration constitutes a microbial fuel cell in which power results from the net oxidation of sediment organic matter by dissolved seawater oxygen. Considering typical sediment organic carbon contents, typical fluxes of additional reduced carbon by sedimentation to sea floors < 1,000 m deep, and the proven viability of dissolved seawater oxygen as an oxidant for power generation by seawater batteries, it is calculated that optimized power supplies based on the phenomenon demonstrated here could power oceanographic instruments deployed for routine long-term monitoring operations in the coastal ocean.

[Chronic liver disease exacerbated during alpha-interferon treatment]. / Hepatopatía crónica exacerbada tras tratamiento con alpha-interferón.

A 27 year old male patient was referred to our clinical unit because of marked elevation of serum bilirubin (up to 15.3 mg/dl), ASAT (563 U/l) and ALAT (845 U/l) were detected after institution of therapy with alpha interferon. The patient had been previously treated because of persistent slight elevation of serum transaminases, serological markers of hepatitis B virus and hepatitis C virus being both negative. Liver histology was consistent with chronic active hepatitis. Antinuclear, anti smooth muscle and antimitochondrial autoantibodies were all negative, although anti smooth muscle antibodies became positive (1/40) after interferon therapy. The drug was withdrawn, prednisone was instituted, and transaminases and bilirubin values returned to normality.

Nutritional assessment of drug addicts.

OBJECTIVE: To discern if factors such as organic pathology, sex, duration and/or intensity of drug addiction, alcohol abuse, hepatitis B infection, anorexia with poor food and drink consumption, or disturbance of social and familial networks, are related to an impaired nutritional status in hospitalized drug addicts. DESIGN: Cross-sectional prospective study. SETTING: Detoxication unit and internal medicine unit of a university hospital. PATIENTS: 140 drug addicts without acute organic pathology and 18 with acute organic pathology related to drug addiction. The immunological study was compared with a control group composed of 50 healthy and well-nourished individuals (26 women and 24 men), age-matched with our patients. RESULTS: Drug addicts without organic pathology were under-nourished: 92.4% weighed under the mean weight for the population and 55.7% had had a weight loss above 5%. The distribution of mid-upper arm circumference (MUAC), triceps skinfold (TSF) measurement and mid-arm muscle area (MAMA) compared with the percentiles for the population showed a shift towards lower values. We found a high percentage of patients with a high lymphocyte count (55%). Despite the high lymphocyte count, delayed hypersensitivity was depressed in our patients. Of our patients, 66.4% exhibited anorexia at admission. The mean calorific intake was 978 +/- 89 kcal/day in females and 1265 +/- 64 kcal/day in males. However, in most cases, malnutrition (usually marasmus-like malnutrition) was not very severe; only 30% of the drug addicts weighed less than 80% of the mean weight for the population, or admitted to a weight loss above 10%, and by subjective nutritional assessment, only 18% were deeply malnourished. Otherwise, the nutritional status was very poor in drug addicts with acute organic pathology. We also found a worse nutritional status in our patients related to female sex, intensity of drug addiction, anorexia with poor food and drink consumption, and disturbance of the social and familial networks. CONCLUSIONS: Many drug addicts suffer from calorie and protein malnutrition. This mainutrition is related to female sex, intensity of drug addiction, anorexia and poor food and drink consumption, and disturbance of the social and familial links. Acute organic pathology leads to a significant worsening of the nutritional status of drug addicts.

Nutritional assessment of drug addicts. Relation with HIV infection in early stages.

OBJECTIVE: To assess the nutritional status of drug addicts without acute organic pathology, in order to determine the prevalence of malnutrition and to discern if early HIV infection is associated with a poor nutritional status in this group of patients. DESIGN: Prospective study. SETTING: Detoxication unit of a university hospital. PATIENTS: 140 drug addicts without acute organic pathology. 31 patients were HIV+. No one fulfilled the definition of AIDS. RESULTS: We found that drug addicts were undernourished: 92.4% weighed under the mean populational weight and 55.7% had a weight loss above 5%. The distribution of mid upper arm circumference (MUAC), triceps skinfold (TSF) and mid arm muscle area (MAMA) was lower than a reference normal population. Food intakes were poor; 66.4% of our patients complained of anorexia on admission. The mean caloric intake was 978 +/- 89 kcal/day in females and 1265 +/- 64 kcal/day in males. The mean protein intakes were 39.3 +/- 3.3 g/day in females (0.76 +/- 0.07 g/kg/day) and 49.7 +/- 2.7 g/day in males (0.77 +/- 0.04 g/kg/day). When we compared nutritional parameters between HIV+ and HIV- patients we found no differences. CONCLUSIONS: Nutritional impairment in drugs abusers with early stages of HIV infection should be attributed to drug abuse rather than to HIV infection.

Ito cells and fibrogenesis in chronic alcoholic liver disease.

The relationships between the number of Ito cells; serum N-terminal type III procollagen and laminin; clinical and biochemical parameters of liver function derangement; histomorphometrically assessed total amount of liver fibrosis; and daily ethanol intake were studied in 43 patients affected by chronic alcoholic liver disease (10 cirrhotics). Significant correlations were found between serum laminin and N-terminal type III procollagen and histological, clinical and biochemical data of liver function derangement, but no correlation was found between the aforementioned parameters and the percentage of Ito cells, which in turn seemed to be related to ethanol ingestion.

[Acute pancreatitis: etiopathogenesis, physiopathology and clinical aspects]. / Pancreatitis aguda: etiopatogenia, fisiopatología y clínica.

Acute pancreatitis is a serious clinical problem. Many of the etiopathogenic mechanisms are not clear and its pathophysiology is very complex, with multisystemic implications. The outcome may be severe, and there is no general agreement on the therapeutic approach. In the present paper we review the newest etiopathogenic and physiopathologic concepts on acute pancreatitis as well as the diagnostic criteria on this condition.

Effects of postnatal administration of ethanol on the M. gastrocnemius of the albino mouse.

A combined morphometric-histochemical (mATPase) study of the effects of ethanol during postnatal development on the m. gastrocnemius has been performed in the albino mouse. The experimental group received ethanol in the drinking water until sacrifice at the age of 40 days. Based on the fiber composition, three different areas are distinguished in the m. gastrocnemius of the mouse. The typical location of these areas does not change after ethanol administration. However, postnatal administration of ethanol produces a selective atrophy and a decrease of the number of type IIb (fast glycolytic) fibers. Concurrently, the number of type IIa (fast oxidative-glycolytic) fibers increases.

Computerized liver imaging: relationship with quantitatively estimated histological parameters in liver cirrhosis.

In liver cirrhosis, increased splenic uptake of radiocolloid, causing the liver-to-spleen (L/S) ratio to decrease, is a characteristic finding, especially during advanced illness. Histologically, advanced liver cirrhosis shows progressive replacement of hepatic parenchyma by fibrous tracts, making it possible to quantify both image and histological parameters. On this basis, the authors performed this study in 39 alcoholic cirrhotic patients in order to determine the relationship between the L/S ratio and right-to-left hepatic lobe ratio (RL/LL) and the degree of fibrosis, fat droplet area, total fat amount, and hepatocyte area. The authors tested if it is possible to predict the degree of fibrosis on the basis of image features or on a combination of image and biochemical parameters, using multiple correlation studies. The degree of fibrosis correlates with the L/S ratio (r = -0.48). The degree of correlation improved using prothrombin, gamma globulin and L/S ratio (r = 0.656), but not enough to allow an accurate estimation of the degree of fibrosis on the basis of a combination of imaging and biochemical data. Neither RL/LL nor L/S ratios significantly correlated with fatty infiltration, fat droplet area, or hepatocyte enlargement. Thus, liver imaging is not useful in quantifying the main histological changes observed in alcoholic liver cirrhosis.

Bone changes in alcoholic liver cirrhosis. A histomorphometrical analysis of 52 cases.

Bone biopsies of 52 histologically confirmed alcoholic cirrhotic patients and 15 age- and sex-matched controls have been histomorphometrically analyzed determining trabecular bone volume (TBV), mineralized bone volume (MBV), and osteoid volume (OV). We also determined serum PTH, 25-OH-D3, calcitonin, FSH, LH, estradiol, testosterone, T3 and T4, urine cortisol, routine liver function tests, serum and urinary calcium, phosphorus, and magnesium. We found a high prevalence of osteoporosis: TBV was significantly lower in cirrhotic patients (T = 7.23, P less than 0.001), 41 of them being in the range of osteoporosis; none of them had osteomalacia. Levels of all the above-mentioned hormones and electrolytes were almost normal, and no correlation was found between them and liver function tests, as occurred with the bone parameters.

Effect of propylthiouracil on liver cell development in the male albino mouse: protective effect against ethanol-induced alterations.

The aim of the present study is to analyze whether the addition of propylthiouracil reverts the influence of ethanol on the development of periportal and pericentral hepatocytes and their nuclei in male albino mice. Propylthiouracil-treated animals showed decreased cellular and nuclear areas when compared with the control animals, except for the 180-day-old animals, whose pericentral cells and nuclei were greater than those of the controls and exhibited fatty infiltration. Pericentral hepatocytes and nuclei of the ethanol-fed animals showed an increase of their sizes, especially in 180-day-old animals. In contrast, hepatocyte and nuclear sizes of the animals treated with both propylthiouracil and ethanol were similar to those of the control group, suggesting a protective effect of propylthiouracil against the ethanol-induced alterations.

Alcohol-induced hypogonadism: reversal after ethanol withdrawal.

Serum testosterone, FSH, LH and prolactin levels have been determined in a group of 32 non-cirrhotic heavy drinkers at 9 and 21 h of the 1st, 3rd, 6th, 11th and 15th days after the onset of a florid ethanol withdrawal syndrome. In addition, serum steroid hormone binding globulin (SHBG) levels were determined at the 1st and 15th days. Serum levels of all these hormones were also determined in a control group of 15 healthy male volunteers. Serum testosterone levels, significantly lower in alcoholics at the beginning of the study, progressively increased along the observation period, recovering the circadian rhythm at the end of it. A significant increase was also observed in serum prolactin levels, in the low and upper limits of the normal range at the beginning and at the end of the study respectively. Serum FSH and LH levels were significantly higher in the alcoholics at the beginning of the study, with no significant variations during the observation period. There was a strong relationship between FSH and LH levels, but not between these hormones and testosterone. Thus, our data suggest that ethanol-induced hypogonadism is primary in origin, functional in nature and transient in its evolution.