Locating and quantifying multiple landfills methane emissions using aircraft data.

A mass balance approach to quantify methane (CH4) emission of four co-located landfills by means of airborne measurements and dispersion modelling was proposed and assessed. By flying grids at different heights above the landfills, atmospheric CH4 densities and wind components were measured along the edges and inside the study atmospheric volume, in order to calculate mass flows in the along- and across-wind directions. A steady-state Gaussian dispersion model was applied to build the concentration fields associated to unit emission from each landfill, while the contribution of each one to the total emission was assessed using a General Linear Model approach, minimizing the difference between measured and modeled mass flows. Results showed that wind spatial and temporal variability is the main factor controlling the accuracy of the method, as a good agreement between measured and modeled mass flows was mainly found for flights made in steady wind conditions. CH4 emissions of the entire area ranged from 213.5 ±â€¯33.5 to 317.9 ±â€¯90.4 g s-1 with a mean value of 252.5 ±â€¯54.2 g s-1. Contributions from individual sources varied from 17.5 to 40.1 g m-2 day-1 indicating a substantial heterogeneity of the different landfills, which differed in age and waste composition. The proposed method was validated against tower eddy covariance flux measurements made at one of the landfills, revealing an overall agreement within 20%.

Therapy of Klebsiella pneumoniae septicaemia in neutropenic rats.

The efficacy of intramuscular gentamicin, sisomicin, tobramycin and amikacin was evaluated in the antimicrobial therapy of septicaemia due to Klebsiella pneumoniae in an experimental model of infection in rats rendered neutropenic by cyclophosphamide. Animals were injected with a LD50 of micro-organisms and 4 hours later treated with a therapeutic i.m. dose of the antibiotics. In animals sacrificed at 0.5, 1 and 4 hours after antibiotic treatment, blood levels of aminoglycosides, bactericidal power of serum and quantitative cultures of peritoneal fluid and blood showed that the four antibiotics tested were effective in drastically reducing the number of bacteria in blood and in the peritoneum, concurrently with the bactericidal power of the serum, though with sisomicin preceding in order of activity gentamicin, amikacin and tobramycin.

[Penetration of amoxicillin into the cerebrospinal fluid]. / Penetrazione dell'amoxicillina nel liquido cerebro-spinale.

The results of a study of the CSF concentration of i.v. amoxicillin in control subjects free of meningeal inflammation are presented. The drug proved capable of passing the blood-brain barrier when employed in sufficiently high doses, even in the absence of meningeal inflammation. The CSF level of the antibiotic was higher than the MIC required for most of the meningeal pathogens.

[Antibacterial activity in vitro of several aminoglycosides and cephalosporins]. / Attivita' antibatterica "in vitro" di alcuni aminoglicosidi e cefalosporine.

The "in vitro" rate of killing on different microorganisms was studied for three cephalosporins (cephazolin, cefuroxime and cefoxitin) and four aminoglycosides (gentamicin, tobramycin, sisomicin and amikacin). In all experiments an inoculum effect and a negative influence by adding plasma to the nutrient broth were observed, the latter phenomenon being more pronounced with cephalosporins than with aminoglycosides. While the "in vitro" effects of antibiotic concentrations equal to the MIC or to the MBC were informing on the intrinsic antibacterial activity of single drugs, a more satisfactory approach to therapeutic reality was provided by studying the "in vitro" effects of concentrations equal to peak blood level or to the logarythmic mean of blood level, that is a parameter which contributes to the blood-tissue diffusion gradient. Our data show that antibiotics provided with an higher peak blood level and a more sustained logarythmic mean of blood concentrations, and an higher ratio between these two kinetics parameters and MIC or MBC, are favoured in the experimental system here adopted.

Bacterial toxins and glucagon in liver cAMP regulation: a physiopathological role in liver diseases?

Alterations of the specific enzymes located in the cell membranes might promote changes of the cyclic nucleotides ratio which is regulatory in growth stimulation of hepatocytes. Bacterial toxins, hormones and drugs affecting cyclic nucleotides system can interfere with this process in liver diseases. The Authors have determined hepatic cAMP concentrations by means of cAMP radioimmunoassay, in vivo, in rats treated with cholera toxin (CT), E. coli endotoxin (LPS) and glucagon. CT (0.15 mg i.v./rat/4th hr) and glucagon (0.8 mg/i.v./10') (significantly p less than 0.01) increase liver cAMP from 1.72 n mol/g wet wt (controls) to 2.62 and 4.13 n mol/g wet/wt respectively. Serum transaminases levels were unmodified. LPS (1.5 mg/hg/i.v./3th hr) significantly (p less than 0.01) raises serum transaminase activity while liver cAMP was not affected. Kinetics study however show that LPS, at lower dosage (0.5 mg/hg i.v.) enhances liver cAMP before cytotoxicity is observed.

Control of endotoxinemia in liver disease by lactulose and paromomycin.

Through the use of the Limulus test research has been carried out on gram-negative endotoxin in patients with hepatic cirrhosis, chronic hepatitis, acute hepatitis, and in a control group. The positivity of this test in patients with cirrhosis and chronic hepatitis was 93.3% and in cases of acute hepatitis it was 90.9%. The effect of the combined administration of lactulose and paromomycin on endotoxin blood levels has been evaluated in a group of 9 patients with acute hepatitis, 8 with cirrhosis, 1 in hepatic coma, and 1 patient with chronic persistent hepatitis: in 18 of the 19 patients the Limulus test became negative. The results have been discussed in relation to clinical and laboratory data, and to recent data concerning the interaction between intestinal bacterial flora, endotoxin, and liver. Hypotheses have been proposed regarding the hepatocellular c-AMP mediated mechanism of endotoxin action.

Post-varicella acute transverse myelitis.

This report of a case of acute transverse myelitis, after otherwise uneventful varicella, further stresses the importance that the possibility of this relatively rare complication should be kept in mind in patients developing a paraplegic syndrome late in the course of the disease.

Investigations on the actions of silybin on regenerating rat liver. Effects on Kupffer's cells.

Studies were conducted on the effects of silybin upon the biological activities of Kupffer's cells in regenerating livers of rats subjected to partial hepatectomy. As far as proliferative activity is concerned, which was assessed by the colchicine stathmokinetic method on Kupffer's cells isolated from the liver by enzymatic digestion, it was appreciably increased in rats treated with silybin in respect of controls. Phagocytic and bactericidal activities were not modified. The increased mitotic activity induced on Kupffer's cells by silybin was interpreted as a further expression of the effectiveness of silybin on the cellular components of the liver.

[Results of a double blind study on the effect of silymarin in the treatment of acute viral hepatitis, carried out at two medical centres (author's transl)]. / Zur Wirkung von Silymarin bei der Behandlung der akuten Virushepatitis. Ergebnis einer an zwei medizinischen Zentren durchgeführten Doppelblindstudie.

In a double blind study carried out under standard conditions at two treatment centers silymarin, 2 sugar-coated tablets 70 mg three times daily, showed a definite therapeutic influence on the characteristic increased serum levels of bilirubin, GOT and GPT associated with acute viral hepatitis. The above mentioned values in 28 patients treated with silymarin were compared with those in 29 patients treated with placebo. The laboratory parameters in the silymarin group regressed more than in the placebo group after the 5th day of treatment. The number of patients having attained normal values after 3 weeks' treatment was higher in the silymarin group than in the placebo group. A statistical comparison revealed a difference between bilirubin and GOT values in the placebo and silymarin groups and a definite trend in the regression of GPT values in favour of silymarin. The course of the immune reaction in HBS Ag patients was not influenced by silymarin. As already proved by other investigators, the use of silymarin in acute viral hepatitis can lead to an accelerated regression in pathological values, thus indicating its use in the treatment of this liver disease.

Inhibiting effect of non-steroidal anti-inflammatory drugs on the chemotaxis of human leukocytes in vitro.

Chemotaxis of human leukocytes was inhibited in vitro by four non-steroidal anti-inflammatory drugs, namely, lysine acetylsalicylate, phenylbutazone, indomethacin, and indoprofen. Dose-dependent effects were always found and significant regression was proved for all drugs except phenylbutazone.