Solid-state culture of Azospirillum brasilense: a reliable technology for biofertilizer production from laboratory to pilot scale.

A biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. A mathematical model was proposed and validated to evaluate the respirometry trends at laboratory and pilot scale exhibiting similar behavior. The cell viability was (1.3 ± 0.4) × 109 and (1.3 ± 0.3) × 109 colony-forming units per gram of initial dry mass at laboratory and pilot scale, at 36 and 43 h, respectively. A. brasilense maintains its viability twelve months of storage at 4 and 30 °C. This is the first report of A. brasilense being cultivated in SSC under controlled conditions. SSC processes involving unicellular microorganisms with tolerance to agitation are a promising technology to produce biofertilizers.

Quantitatively characterizing benthic community-habitat relationships in soft-sediment, nearshore environments to yield useful results for management.

Effective management of benthic habitats is important for maintaining heathy and functional aquatic ecosystems. To provide managers with the best possible information, characterizing benthic habitats at the community level is essential; yet, acquiring the data sets needed to achieve this task is resource intensive and, at times, prohibitively expensive. Thus, thoughtful assessments of which data to collect and utilize in benthic habitat characterization studies are needed. Environmental data sets commonly used to characterize benthic habitats include a range of variables from water depth and sediment grain size to seabed features identified by sonar backscatter. The objective of this study was to identify the most useful environmental variables for characterizing infaunal benthic habitats and to determine how to best utilize these variables in analyses (e.g., by comparing continuous vs. categorical explanatory variables). The modeling approach used multivariate regression tree and redundancy analysis along with a critical cross-validation step for model evaluation. Results indicated that models with more than ~7 environmental predictors overfitted the data sets analyzed and that categorizing continuous predictors into categorical ones influenced the proportion of infaunal community variation explained by each model. Habitats identified and characterized on the basis of sonar backscatter explained more of the infaunal community variation than any model that used a combination of other environmental variables (e.g., water depth & sediment grain size) or those constructed using categorical habitat classes from existing classification schemes. We therefore recommend maximizing the potential of sonar-derived variables for characterizing infaunal benthic habitats in nearshore, soft-sediment ecosystems.

Top predators induce habitat shifts in prey within marine protected areas.

Emerging conservation efforts for the world's large predators may, if successful, restore natural predator-prey interactions. Marine reserves, where large predators tend to be relatively common, offer an experimental manipulation to investigate interactions between large-bodied marine predators and their prey. We hypothesized that southern stingrays-large, long-lived and highly interactive mesopredators-would invest in anti-predator behavior in marine reserves where predatory large sharks, the primary predator of stingrays, are more abundant. Specifically, we predicted southern stingrays in marine reserves would reduce the use of deep forereef habitats in the favor of shallow flats where the risk of shark encounters is lower. Baited remote underwater video was used to survey stingrays and reef sharks in flats and forereef habitats of two reserves and two fished sites in Belize. The interaction between "protection status" and "habitat" was the most important factor determining stingray presence. As predicted, southern stingrays spent more time interacting with baited remote underwater videos in the safer flats habitats, were more likely to have predator-inflicted damage inside reserves, and were less abundant in marine reserves but only in the forereef habitat. These results are consistent with a predation-sensitive habitat shift rather than southern stingray populations being reduced by direct predation from reef sharks. Our study provides evidence that roving predators can induce pronounced habitat shifts in prey that rely on crypsis and refuging, rather than active escape, in high-visibility, heterogeneous marine habitats. Given documented impacts of stingrays on benthic communities it is possible restoration of reef shark populations with reserves could induce reef ecosystem changes through behavior-mediated trophic cascades.

Similar antibody response observed in single-dose-vaccination vs. revaccination against Aujeszky's disease in wild boar.

Wild boar is an important reservoir of Aujeszky's disease virus (ADV). There is concern that transmission of this virus from wild boar to domestic pigs is possible. The aim of this work was to compare the antibody response produced by single dose of a gE-deleted ADV vaccine in wild boar to revaccinated animals, to assess if simple single-dose vaccination plans should be examined as a possible control measure against ADV in wild boar. Twenty-five wild boar (ages ranging between 2.5 to 5 months) were included in this study and distributed in three different groups: a control group (n = 5), a single-dose group (10 animals vaccinated only with one dose (day 0)) and a revaccinated group [10 animals vaccinated (day 0) and revaccinated (day 28)]. Mean antibody titers against ADV were determined in three groups using an ELISA assay at three different time points [day 0 (pre-vaccination), 28 (post 1st dose) and 56 (post 2nd dose)]. At day 28, single-dose and revaccinated groups showed a significant increment of antibody titers whereas antibodies in the control group remained stable. At day 56, revaccinated animals did not show a significant increment and antibody titers were similar to those found in animals vaccinated with one dose. These results indicate that vaccination with one dose produces a similar early antibody response to revaccination and therefore, should be examined as a possible control measure against ADV in wild boar. Keywords: Aujeszky's disease; serology; vaccination; wild boar.

Association between vitamin D supplementation and severity of tuberculosis in wild boar and red deer.

Tuberculosis (TB) is a chronic disease affecting humans and other mammal species. Severity of TB caused by Mycobacterium tuberculosis in humans seems to be influenced by nutritional factors like vitamin D3 intake. However, this relationship has been scarcely studied in cattle and other mammals infected with Mycobacterium bovis. The aim of this work was to assess if wildlife reservoirs of M. bovis show different levels of TB severity depending on the level of vitamin D found in serum after supplementation with vitamin D3. Forty hunted wildlife mammals were included in this study: 20 wild boar and 20 red deer. Ten wild boar and ten red deer had been supplemented with a vitamin D3-enriched food, whereas the remaining animals had received no supplementation. TB diagnosis was carried out in each animal based on microbiological isolation of M. bovis. Animals infected with M. bovis were then classified as animals with localized or generalized TB depending on the location and dissemination of the lesions. Furthermore, serum levels of vitamin D2 and D3 were determined in each animal to evaluate differences not only between supplemented and non-supplemented animals but also between those with localized and generalized TB. Levels of vitamin D3 found in both, supplemented wild boar and red deer, were significantly higher than those found in the non-supplemented animals. Interestingly, higher levels of vitamin D3 were observed in animals suffering localized TB when compared to animals with generalized TB suggesting that vitamin D3 concentration correlates negatively with TB severity in these wildlife reservoirs.

Instability of an aromatic amine in fatty food and fatty food simulant: characterisation of reaction products and prediction of their toxicity.

It is a well-known fact that amines are not stable in food of a fatty nature. In this study the synthesis and characterisation of the products obtained as a result of the reaction of amines in a fatty medium are reported. Based on the well-known reactions among amines and acid and esters groups, two novel compounds were synthesised using m-xylylenediamine (mXDA), a primary diamine widely used as monomer in the manufacture of food contact materials and two fatty acids, oleic acid and palmitic acid, which occur in most fats. The resulting compounds were two molecules belonging to the family of fatty acid amides, dioleamide and dipalmitamide. A complete characterisation of both products was carried out employing several techniques such as infrared spectroscopy, (1)H- and (13)C-NMR spectroscopy, electron ionisation mass spectrometry, LC-MS/MS and UV spectrometry. The results obtained by the different techniques were well correlated. In the second part of the work, the formation of these compounds in real samples was evaluated. For this purpose a certain volume of olive oil was spiked with a known amount of mXDA. Olive oil was selected as a fatty medium since it is a widely consumed food and additionally is used as a fatty food simulant in migration studies of food contact materials. A method was developed to extract the fatty acid amides from the fatty matrix, which were then identified by LC-MS/MS. The toxicity of the synthesised compounds was predicted using a toxicity estimation software tool.

Non-tuberculous mycobacteria in wild boar (Sus scrofa) from Southern Spain: epidemiological, clinical and diagnostic concerns.

Non-tuberculous mycobacteria (NTM) are widely distributed in the environment, particularly in wet soil, marshland, rivers or streams, but also are causative agents of a wide variety of infections in animals and humans. Little information is available regarding the NTM prevalence in wildlife and their effects or significance in the bovine tuberculosis (bTB) epidemiology and diagnosis. This research shows the most frequently NTM isolated in lymph nodes of wild boar (Sus scrofa) from southern Spain, relating the NTM presence with the individual characteristics, the management of animals and the possible misdiagnosis of Mycobacterium bovis in concurrent infections. A total of 219 NTM isolates were obtained from 1249 wild boar mandibular lymph nodes sampled between 2007 and 2011. All but 75 isolates were identified by the PCR-restriction analysis-hsp65, and a partial sequencing of the 16S rDNA was carried out to identify the rest of the isolates. Results showed that Mycobacterium chelonae was the most frequently isolated NTM specie (133 isolates, 60.7%), followed by Mycobacterium avium (24 isolates, 11%). No relation was found regarding sex, body condition and management, but M. chelonae was more frequently detected in adults, whereas M. avium was more prevalent in subadults. The high NTM prevalence observed in the studied wild boar populations could make difficult the bTB diagnostic.

Development of a rapid screening method to determine primary aromatic amines in kitchen utensils using direct analysis in real time mass spectrometry (DART-MS).

Primary aromatic amines (PAAs) are a group of substances with undesirable health effects, that are used in a variety of commercial products. Several recent studies, using a number of screening and confirmatory methods, have reported the migration of PAAs from some kitchen utensils into acetic acid 3% (w/v). Many of these methods require significant sample preparation, therefore the aim of this work was to determine if direct analysis in real time mass spectrometry (DART-MS) could be utilised as a rapid screening tool for the determination of PAAs in kitchen utensils. DART-MS results from direct analysis of the utensil have been compared with results of PAA migration by ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The UPLC-MS/MS method had excellent linearity, appropriate sensitivity (LOD ≤ 1.5 µg L(-1); LOQ ≤ 4.5 µg L(-1)), repeatability from 2.4 to 13.2% and acceptable recoveries. DART-MS results were in good agreement with UPLC-MS/MS data, with 100% of non-compliant (PAA positive) samples successfully identified by DART-MS.

Reducing Eurasian wild boar (Sus scrofa) population density as a measure for bovine tuberculosis control: effects in wild boar and a sympatric fallow deer (Dama dama) population in Central Spain.

Research on management of bovine tuberculosis (bTB) in wildlife reservoir hosts is crucial for the implementation of effective disease control measures and the generation of practical bTB management recommendations. Among the management methods carried out on wild species to reduce bTB prevalence, the control of population density has been frequently used, with hunting pressure a practical strategy to reduce bTB prevalence. However, despite the number of articles about population density control in different bTB wildlife reservoirs, there is little information regarding the application of such measures on the Eurasian wild boar (Sus scrofa), which is considered the main bTB wildlife reservoir within Mediterranean ecosystems. This study shows the effects of a management measure leading to a radical decrease in wild boar population density at a large hunting estate in Central Spain, in order to assess the evolution of bTB prevalence in both the wild boar population and the sympatric fallow deer population. The evolution of bTB prevalence was monitored in populations of the two wild ungulate species over a 5-year study period (2007-2012). The results showed that bTB prevalence decreased in fallow deer, corresponding to an important reduction in the wild boar population. However, this decrease was not homogeneous: in the last season of study there was an increase in bTB-infected male animals. Moreover, bTB prevalence remained high in the remnant wild boar population.

Endothelin-1 increases superoxide production in human coronary artery bypass grafts.

AIMS: Endothelin-1 (ET-1) has been shown to increase endothelial superoxide (O(2)(-)) production in experimental animal models. It is unclear whether ET-1 increases O(2)(-) production in humans. We sought to elucidate whether ET-1 increases O(2)(-) production in human vessels and to identify the mechanism behind this effect. MAIN METHODS: Segments of internal mammary artery (IMA) and human saphenous vein (HSV) were harvested from 90 patients undergoing elective coronary artery bypass graft surgery. Paired vessel rings were incubated in the presence and absence of ET-1 (10(-10)M), the ET(A) receptor antagonist BQ123 alone, or in combination with the ET(B) receptor antagonist BQ788 (dual BQ) and known inhibitors of sources of O(2)(-) and further analysed for O(2)(-) production using lucigenin-enhanced chemiluminescence and DHE fluorescence. KEY FINDINGS: ET-1 increased O(2)(-) production in both IMA (2.6 ± 1.5 vs. 1.4 ± 0.8 relative light units/s/mg tissue (RLU); n=33; p < 0.0001) and HSV (1.4 ± 0.8 vs. 1.1 ± 0.6 RLU; n=24; p<0.05). The increase in O(2)(-)production induced by ET-1 in IMA was inhibited by co-incubation with dual BQ (p < 0.05; n=15) and BQ123 (p<0.05; n = 17). Of known O(2)(-) inhibitors, only incubation with Tiron and diphenyleneiodonium resulted in a significant reduction in ET-mediated O(2)(-) production. SIGNIFICANCE: ET-1 increases O(2)(-) production especially in human arteries and less so in veins from patients with coronary artery disease via a receptor-dependent pathway involving a flavin dependent enzyme which is likely to be NADPH oxidase. Production of O(2)(-) may be an important factor underlying the negative effects of ET-1 on vascular function such as impairment of endothelium-dependent vasodilatation and pro-inflammatory effects.

Analytical method for the simultaneous determination of polyfunctional amines used as monomers in the manufacture of food packaging materials.

This paper describes the development of a multi-analyte method for the determination of polyfunctional amines commonly used as monomers in the manufacture of food contact materials. Amines were analyzed by high-performance-liquid chromatography with diode-array detection (HPLC-DAD) after derivatization with dansyl chloride. The chromatographic analysis and the derivatization conditions were optimized. The proposed method was validated in terms of linearity, limits of detection and repeatabilities. The method showed an excellent sensitivity (LOD≤0.05 µg/mL) and appropriate repeatabilites (RSD (n=7)≤5%)). LC-MS/MS was used as a confirmatory technique. The stability of the amines in five food simulants (distilled water, 3% acetic acid, 10% ethanol, 50% ethanol and olive oil) under the most common testing conditions (10 days at 40 °C) was also studied. Results showed that amines had an acceptable stability in aqueous simulants but in the olive oil a loss of 100% was observed for all analytes.

Pediococcus acidilactici isolated from the rumen of lambs with rumen acidosis, 16S rRNA identification and sensibility to monensin and lasalocid.

A lactic-acid producing bacterium was isolated from the rumen of lambs with rumen acidosis. The cells were gram-positive, nonmotile, nonsporing, catalase negative spherical, 1.5-2.0 µm in diameter, and occur in pairs and tetrads. Analysis of 16S ribosomal RNA indicated that the rumen bacterium was a strain of Pediococcus acidilactici with 99% of nucleotide homology. This bacterium was sensible to monensin and lasalocid at the unique dose tested of 300 ppm. The concentration of lactic acid and DM degradation decreased (P<0.05) when monensin or lasalocid were added to the culture media after 24, 48 and 72 h of incubation. In contrast, total VFA concentration and pH were higher (P<0.05) in the culture media added with the ionophores. Up to now S. bovis is considered the main ruminal bacterium related with rumen acidosis, but the importance of P. acidilactici should be also reconsidered in experimental studies focused on the control rumen acidosis.

Rapid multi-analyte quantification of benzophenone, 4-methylbenzophenone and related derivatives from paperboard food packaging.

Photo-initiators are used in printing inks hardened with UV light and one of the most commonly used photo-initiators is benzophenone (BP). Recent notifications under the Rapid Alert System for Food and Feed have shown migration of 4-methylbenzophenone (4-MBP) from packaging into cereals. A specific migration limit exists for BP of 0.6 mg kg(-1) for its use as an additive in plastics. There is no specific European legislation covering cardboard boxes and/or printing inks for food contact use. However, due to the high levels detected, the European Food Safety Authority (EFSA) published recommendations and the Standing Committee for the Food Chain and Animal Health endorsed a limit of 0.6 mg kg(-1) for the sum of BP and 4-MBP. While studies have been published on photo-initiators in the past, there is a fundamental lack of data on 4-MBP especially for its combined analysis with others. We present an HPLC method with diode array detector to simultaneously determine the levels of BP, 4-MBP as well as 7 other possible derivatives from secondary packaging for food applications. The method was tested and applied to 46 samples of paperboard for secondary packaging collected both from supermarkets and directly from a paperboard supplier. In addition, a survey was conducted on recycled paperboard (n = 19) collected from a supplier, to evaluate the background quantity of BP and other derivatives in recycled board. The most abundant photo-initiator found in the survey was BP, in 61% of samples, and 4-MBP was found in 30% of the samples. It seems that these compounds are used to replace one another. Other derivatives were found in minor quantities. Traces of BP were also found in 42% of the samples of recycled, unprinted board.

Bovine tuberculosis in wild boar (Sus scrofa), red deer (Cervus elaphus) and cattle (Bos taurus) in a Mediterranean ecosystem (1992-2004).

During the last 12 years, an increasing frequency in condemnation of hunted red deer and wild boar carcasses due to the presence of tubercle-like lesions has been observed in Extremadura (Western Spain). Before 1993, tuberculosis was a very rare finding in hunted animals. The current tuberculosis regional prevalence in cattle approaches 0.4% after years of expensive test and slaughter campaigns. It is imperative to investigate the epidemiology of Mycobacterium bovis infection in red deer and wild boar in order to keep a good health status and to maintain the effectiveness of domestic species TB eradication programs. The present paper evaluates the problem in Sierra de San Pedro, estimating the prevalence of TB in wild boar and red deer, the main wild artiodactyls in the area, and domestic cattle since 1992-2004, by the use of a low-cost surveillance method based on detailed pathological inspection of hunted animal carcasses. Microbiology and molecular epidemiology studies on several M. bovis isolates from domestic and wild animals helped to define the interspecies contacts. These findings, as well as recent history of game estates management and descriptive epidemiology field work, throw light on the rise and maintenance of these epizootics.

Effect of combined nutrients on biosurfactant produced by Pseudomonas putida.

This work investigated biosurfactant production by Pseudomonas putida in combined C/P, C/Ninorganic, C/Fe, C/Mg nutrient ratios and peptone concentration. Analysis of the 2(5-1) fractional factorial experimental design showed that only the C/Fe ratio had a significant (p<0.02) effect on biosurfactant production. The highest amount of biosurfactant was obtained at low C/Fe ratios, but net surface tension did not show significant differences. In addition, low amounts of peptone and the C/P-C/Mg nutrient ratios interaction significantly (p < 0.05) enhanced the biomass produced by P. putida. Analysis of biosurfactant by gas chromatography (GC) showed that the hydrophilic fraction was composed by rhamnose and the hydrophobic fraction, mainly by palmitic (C16), stearic (C18:0), oleic (C18:1) and linoleic (C18:2) fatty acids.

[Factors related to diagnostic yield and complications of transbronchial biopsy]. / Factores relacionados con la rentabilidad diagnóstica y aparición de complicaciones de la biopsia transbronquial.

To study the diagnostic yield of transbronchial biopsy (TBB) in lung diseases of different ethiology, as well as to examine several factors implicated in diagnostic yield and complications of TBB. Retrospective study of a series of 172 patients (98 women and 74 men) undergoing TBB. Clinical variables, x-ray and CT patterns and technical factors related to TBB were analyzed in relation to diagnostic yield and definitive diagnosis. We recorded the main complications and studied the possible mechanisms implicated in their appearance. The results of TBB were classified as follows: 1) diagnostic TBB (42.8%); 2) nonspecific TBB (21.1%); absence of parenchyma (NP) (9.7%); 4) normal parenchyma (23.4%); 5) incorrect diagnosis (2.9%). Overall yield was 43.6% but rose to 52% when NP and no infiltrative pneumopathies were excluded. The main findings were infections (23.4%), neoplasms (19.4%), sarcoidosis (14.2%), idiopathic pulmonary fibrosis (IPF) (17.7%); and other (23.4%). Significant differences in diagnosis were found for age, sex, time of evolution prior to TBB, and x-ray and CT patterns. Complications and pneumothorax appeared more frequently in IPF, neoplasms and infections, although the differences were non significant. Diagnostic value depended mainly on type of disease and ranged from 60% for sarcoidosis to 24% for IPF (p < 0.05), with no differences related to age, sex, presence of immunosuppression, number of TBB or tolerance to exploration. Yield was higher, however, for patients with no loss of radiographic pulmonary volume (56.3% versus 37.5%) and with absence of a CT reticular pattern (44.7% versus 27.3%). Type of opacites also influenced yield (53.4% for ground glass versus 26.7% for reticular patterns), as did distribution of lesions (8.4% for peripheral patterns versus 48.3% for diffuse patterns and 50% for peribronchio-vascular patterns). The site of TBB was the only factor showing clearly significant differences in yield (100% in mild lobe versus 29.5% in upper lobes). Tolerance was poorer in older patients (63.5 +/- 10 versus 52.2 +/- 17 years) and with greater function abnormalities (%FEV1: 48.2 +/- 16.8 versus 70.2 +/- 17.1). Poor tolerance of exploration was associated with the appearance of complications (16.6% vs 6.3) and pneumothorax (25% versus 6.8%). The diagnostic yield of TBB was mainly influenced by the type of disease studied. The various imaging techniques were fundamental for establishing preliminary diagnoses and degree of evolution of a specific cases. In our series, tolerance of the technique was a reliable predictor of complications and the presence of post-biops pneumothorax.

Thoracic empyema in HIV-infected patients: microbiology, management, and outcome.

OBJECTIVES: To evaluate etiology, bacteriology, stage of disease, treatment, and outcome of HIV-infected patients with thoracic empyema (TE) over a 9-year period at a hospital teaching center. DESIGN: We have retrospectively reviewed the charts of all HIV-infected patients with a hospital discharge diagnosis of empyema between January 1985 and November 1993. PATIENTS: Twenty-three patients were identified (22 male and 1 female). The average patient age was 28.7+/-5.3 years. All the patients were injection-drug users, and 10 (43%) fulfilled criteria for an AIDS diagnosis. In 15 cases (65%), the empyema was the first cause of medical consultation, which then led to an HIV infection diagnosis in 11 of them (48%). MEASUREMENTS: In each case, symptoms, chest studies, culture results, procedure timing, length of hospitalization, and outcome were reviewed. RESULTS: Twenty-one patients (91%) had developed an empyema secondary to community-acquired pneumonia. The cultures of pleural fluid were positive in 19 cases (83%). Anaerobes were isolated from 6 patients and aerobes from 13. A single bacteria was isolated from 10 (52%), and multiple organisms (average 2.66 per case) grew in the remaining 9 positive cultures. The most common organism culture growths were Staphylococcus aureus (23%) and Gram-negative bacilli (36%). Length of hospitalization averaged 25.6 days (+/-15). Intercostal tube drainage was necessary in 18 patients and none required surgery. Patients with AIDS diagnosis needed a longer period of hospitalization, and the presence of bacteremia and bronchopleural fistula was more frequent. However, this did not influence a patient's final outcome. A follow-up was available in 18 cases, with 4 deaths recorded (average survival, 35 months; range, 4 to 84 months). CONCLUSIONS: In our series, TE associated with HIV infection was often the primary cause leading to hospital admission and later HIV diagnosis. IV drug abuse was the predominant factor for HIV infection and was also related to clinical presentation and microbiological findings. The best approach to treatment is--as with other patient groups--a prompt drainage and appropriate antibiotic treatment, since a favorable outcome is expected.

Ribotyping of Fusobacterium necrophorum strains isolated from bovine and ovine hepatic abscesses.

A microbiological study was made of 100 strains of Fusobacterium necrophorum isolated from hepatic abscesses in bovine and ovine herds. Differences between the biological activity and ribotypes within the two F. necrophorum subspecies were studied. Conventional methods identified 89 isolates as F. necrophorum subsp. necrophorum and 11 as F. necrophorum subsp. funduliforme. For ribotyping, 50 strains (35 F.n. subsp. necrophorum, 11 F.n. subsp. funduliforme and 4 reference strains) were digested with restriction endonucleases (HindIII, EcoRI and BamHI) and examined after hybridization with digoxigenin-labelled cDNA probe transcribed from a 16 and 23S rRNAs from Escherichia coli. The most discriminating restriction endonuclease enzymes for ribotyping were EcoRI and BamHI. The presence or absence of two distinct band of 5 kb (EcoRI) and 10.5 kb (BamHI) differentiated the two subspecies. This technique also revealed genetic differences between isolates which could be used in the epidemiological study of clinical processes caused by F. necrophorum.

[Pseudochylothorax. Review of 5 cases]. / Seudoquilotórax. Revisión de 5 casos.

We undertook a retrospective review of five patients with pseudo-chylothorax diagnosed at our hospital between 1984 and 1994. Pseudo-chylothorax was diagnosed if crystals of cholesterol were observed (CC) or if cholesterol concentrations were over 150 mg/dl, but chylomicrons were absent from pleural effusions with cloudy supernatants after centrifugation. The five patients were males and their mean age was 53 years. All had history of pulmonary or pleural tuberculosis (mean 31 years since diagnosis). All had received chemotherapy and four had undergone therapeutic pneumothorax. Two patients were diagnosed in the course of examination for other reasons, Three were diagnosed while being examined for the cause of pleural effusion. The diagnosis of four patients was based on the presence of CC. Three patients received specific treatment and Mycobacterium tuberculosis was isolated in the pleural fluid of two. One patient required a pleural drain and antibiotics because of empyema related to pseudo-chylothorax. Decortication was needed by two. 1) Pseudo-chylothorax is at present rare. 2) All the cases we saw were associated with earlier tuberculosis infection with residual pleural lesions. 3) Diagnosis usually occurs in the course of examination for the other motives, but the possibility of infected pleural effusion or reactivation of tuberculosis should be considered.

Survival of Azospirillum brasilense in the Bulk Soil and Rhizosphere of 23 Soil Types.

The survival of Azospirillum brasilense Cd and Sp-245 in the rhizosphere of wheat and tomato plants and in 23 types of plant-free sterilized soils obtained from a wide range of environments in Israel and Mexico was evaluated. Large numbers of A. brasilense cells were detected in all the rhizospheres tested, regardless of soil type, bacterial strain, the origin of the soil, or the amount of rainfall each soil type received prior to sampling. Survival of A. brasilense in soils without plants differed from that in the rhizosphere and was mainly related to the geographical origin of the soil. In Israeli soils from arid, semiarid, or mountain regions, viability of A. brasilense rapidly declined or populations completely disappeared below detectable levels within 35 days after inoculation. In contrast, populations in the arid soils of Baja California Sur, Mexico, remained stable or even increased during the 45-day period after inoculation. In soils from Central Mexico, viability slowly decreased with time. In all soils, percentages of clay, nitrogen, organic matter, and water-holding capacity were positively correlated with bacterial viability. High percentages of CaCO(inf3) and fine or rough sand had a highly negative effect on viability. The percentage of silt, pH, the percentage of phosphorus or potassium, electrical conductivity, and C/N ratio had no apparent effect on bacterial viability in the soil. Fifteen days after removal of inoculated plants, the remaining bacterial population in the three soil types tested began to decline sharply, reaching undetectable levels 90 days after inoculation. After plant removal, percolating the soils with water almost eliminated the A. brasilense population. Viability of A. brasilense in two artificial soils containing the same major soil components as the natural soils from Israel did was almost identical to that in the natural soils. We conclude that A. brasilense is a rhizosphere colonizer which survives poorly in most soils for prolonged periods of time; that outside the rhizosphere, seven abiotic parameters control the survival of this bacterium in the soil; and that disturbance of the soil (percolation with water or plant removal) directly and rapidly affects the population levels.