Trophic Path of Marked Exuviae Within Colonies of Coptotermes gestroi (Blattodea: Rhinotermitidae).

Nitrogen, a limiting growth factor in wood-feeding insects, was hypothesized to play a role in the recently discovered behavior of subterranean termites returning to the nest to molt. Coptotermes gestroi (Wasmann) exuviae is approximately 11% N by dry weight, and therefore a potentially rich source of recyclable nitrogen. Exuviae from a C. gestroi colony were marked with immunoglobulin G (IgG) and were fed to two-year-old C. gestroi colonies. IgG-marked exuviae were detected with an enzyme-linked immunosorbent assay. The IgG marker was later detected in every caste and life stage except first-instar larvae (L1). The proportion of individuals positive for the marker varied by caste, with the queens always being positive for the marker. The queens and second-or-higher-instar workers (W2+) had significantly higher concentrations of the marker than the eggs and L1. The trophic path of exuviae includes individuals that directly fed on marked exuviae (workers and possibly second-instar larvae) and individuals that secondarily received marked exuviae through trophallaxis (queens, kings, and soldiers). This study described the trophic path of consumed exuviae and demonstrated its role in the recycling of nitrogen in a subterranean termite. Molting at the central nest may be an efficient means to transfer nitrogen from shed exuviae to recipients and may be a nitrogen recycling behavior conserved from a termite ancestor.

Exuviae Recycling Can Enhance Queen Oviposition and Colony Growth in Subterranean Termites (Blattodea: Rhinotermitidae: Coptotermes).

Wood-feeding termites have a nitrogen-poor diet and have therefore evolved nitrogen conservation strategies. However, termite workers molt periodically, and throughout the lifetime of a colony, millions of exuviae, a nitrogen-rich resource, are produced by the colony. In Coptotermes Wasmann, workers foraging at remote feeding sites must return to the central part of the nest to molt, where the queen, king, eggs, and larvae are located. It was hypothesized that this molting-site fidelity is an efficient way to recycle nitrogen for reproduction and colony growth, as nestmates involved in exuviae consumption can directly transfer such resources to individuals engaged in reproduction (the queen) or growth (larvae). This study investigates whether incipient colonies of C. gestroi (Wasmann) can gain additional biomass when they are fed supplementary exuviae. Incipient colonies were reared in nitrogen-poor or nitrogen-rich conditions, and 0, 1, 5, or 10 exuviae were added to 3-month-old colonies. After 6.5 months, colonies reared in nitrogen-poor environments gained significantly more biomass when exuviae were added than colonies with no added exuviae. However, the addition of exuviae had no effect on colony growth for colonies reared in nitrogen-rich environments. In a second experiment, queens from colonies in which exuviae were effectively removed laid fewer eggs than queens from colonies in which exuviae were not removed. Therefore, consumption of exuviae from molting individuals by nestmates is an important part of the nitrogen recycling strategy in Coptotermes colonies, as it facilitates queen oviposition and colony growth, especially when such colonies have limited access to nitrogen-rich soils.

Impact of the Recent Measurements of the Top-Quark and W-Boson Masses on Electroweak Precision Fits.

We assess the impact of the very recent measurement of the top-quark mass by the CMS Collaboration on the fit of electroweak data in the standard model and beyond, with particular emphasis on the prediction for the mass of the W boson. We then compare this prediction with the average of the corresponding experimental measurements including the new measurement by the CDF Collaboration, and discuss its compatibility in the standard model, in new physics models with oblique corrections, and in the dimension-six standard model effective field theory. Finally, we present the updated global fit to electroweak precision data in these models.

Nitrogen content of the exuviae of Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae).

Subterranean termites are hemimetabolous social insects where most of the individuals in a colony molt on a regular basis until they die. Nitrogen is a limiting growth factor in wood-feeding insects, such as termites. Because the exuviae of molting termites are consumed by nestmates, it is possible that exuviae represent a potential source of nitrogen that could be recycled and be part of the overall nitrogen conservation strategy of the colony. Although it was documented that cockroach exuviae can contain relatively high levels of nitrogen, the nitrogen content of subterranean termite exuviae has not been examined. This study determines the nitrogen content of Coptotermes gestroi (Wasmann) exuviae collected from four-year-old laboratory colonies using a carbon/nitrogen analyzer. Coptotermes gestroi exuviae contained 11.24 ± 0.64% N (Mean ± SD). The exuviae had a higher proportion of nitrogen than whole bodies of termites (~10.46%), wood (~0.12%), and organic soil (~2.49%). These results support the importance of exuviae consumption by nestmates during the ecdysis process as an aspect of nitrogen conservation strategies in Coptotermes colonies.

Methoprene-Induced Genes in Workers of Formosan Subterranean Termites (Coptotermes formosanus Shiraki).

Termites have a distinct polyphenism controlled by concise hormonal and molecular mechanisms. Workers undergo double molts to transform into soldiers (worker-presoldier-soldier). Juvenile hormone analogs, such as methoprene, can induce workers to transform into presoldiers. However, the molecular mechanism underlying the worker-to-presoldier transformation in Coptotermes formosanus Shiraki is still not clear. We sequenced the transcriptome of workers four days after they had fed on methoprene-treated filter paper and control group workers, which fed on acetone-treated filter paper. The transcriptome of C. formosanus was assembled using the de novo assembly method. Expression levels of unigenes in the methoprene-treated group and the control group were compared. The differentially expressed genes were further analyzed by Gene Ontology (GO) term enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Tetrapyrrole binding, oxidoreductase activity, and metal ion binding were the only three enriched GO terms. Juvenile hormone synthesis was the first ranked enriched pathway. Carbohydrate, amino acid, and lipid metabolism pathways were also enriched. These three pathways may be related to fat body development, which is critical for presoldier formation. Our results have demonstrated the significance of JH synthesis pathways, and pathways related to fat body development in the artificial induction of presoldiers.

Brucella Exposure Risk Events in 10 Clinical Laboratories, New York City, USA, 2015 to 2017.

From 2015 to 2017, 11 confirmed brucellosis cases were reported in New York City, leading to 10 Brucella exposure risk events (Brucella events) in 7 clinical laboratories (CLs). Most patients had traveled to countries where brucellosis is endemic and presented with histories and findings consistent with brucellosis. CLs were not notified that specimens might yield a hazardous organism, as the clinicians did not consider brucellosis until they were notified that bacteremia with Brucella was suspected. In 3 Brucella events, the CLs did not suspect that slow-growing, small Gram-negative bacteria might be harmful. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), which has a limited capacity to identify biological threat agents (BTAs), was used during 4 Brucella events, which accounted for 84% of exposures. In 3 of these incidents, initial staining of liquid media showed Gram-positive rods or cocci, including some cocci in chains, suggesting streptococci. Over 200 occupational exposures occurred when the unknown isolates were manipulated and/or tested on open benches, including by procedures that could generate infectious aerosols. During 3 Brucella events, the CLs examined and/or manipulated isolates in a biological safety cabinet (BSC); in each CL, the CL had previously isolated Brucella Centers for Disease Control and Prevention recommendations to prevent laboratory-acquired brucellosis (LAB) were followed; no seroconversions or LAB cases occurred. Laboratory assessments were conducted after the Brucella events to identify facility-specific risks and mitigations. With increasing MALDI-TOF MS use, CLs are well-advised to adhere strictly to safe work practices, such as handling and manipulating all slow-growing organisms in BSCs and not using MALDI-TOF MS for identification until BTAs have been ruled out.

Functional Traits Explain Variation in Chaparral Shrub Sensitivity to Altered Water and Nutrient Availability.

Worldwide drylands are threatened by changes in resource availability associated with global environmental change. Functional traits may help predict which species will be most responsive to these alterations in nutrient and water availability. Current functional trait work focuses on tissue construction and nutrient concentrations, but plant performance in low resource environments also may be strongly influenced by traits related to nutrient budgets and allocation. Our overall objective was to compare trait responses in a suite of serpentine and nonserpentine congener pairs from the California chaparral, a biodiverse region facing nutrient deposition and future changes in precipitation. In a common garden greenhouse environment, we grew small plants of Arctostaphylos manzanita, A. viscida, Ceanothus cuneatus, C. jepsonii, Quercus berberidifolia, and Q. durata in contrasting soil nutrient and moisture treatments. We measured a suite of traits representing physiological, growth, and mineral nutrient responses to these treatments. Overall, plant growth rate and leaf-level phosphorus use efficiency were greatest in the low water, high nutrient treatment, and lowest in the high water, low nutrient treatment. Variation in growth rate and plasticity among species and treatments was primarily associated with differences in mineral nutrition-based traits as opposed to differences in biomass allocation or specific leaf area. Namely, faster growing species and species with greater plasticity allocated more nitrogen and phosphorous to leaves and demonstrated greater photosynthetic phosphorus use efficiency. Overall, nonserpentine species had greater plasticity and biomass response to resource addition than serpentine species, and congener pairs responded to these resource additions more similarly to each other than species across congener pairs. This study extends our general understanding of how functional traits may influence species responses to environmental change and highlights the need to integrate mineral nutrition-based traits, including allocation of nutrient pools and nutrient use efficiency into this larger trait framework. Ultimately, this insight can help identify, in part, why coexisting species may vary in sensitivity to anthropogenic driven changes in soil resource availability.

Comparison of Temperature-Dependent Survivorship and Wood-Consumption Rate Among Two Invasive Subterranean Termite Species (Blattodea: Rhinotermitidae: Coptotermes) and Their Hybrids.

Two invasive subterranean termite species, Coptotermes formosanus Shiraki and Coptotermes gestroi Wasmann (Blattodea: Rhinotermitidae), established in South Florida have the potential to hybridize owing to their sympatric distribution, overlapping dispersal flight seasons, and interspecies mating behavior. This study examined the effects of temperature on survivorship and wood-consumption rate (WCR) to determine the potential of such hybrid termites as structural pests. Temperature tolerance was tested using groups of termites from incipient colonies established in the laboratory with four mating types (♀C. gestroi × â™‚C. gestroi, ♀C. formosanus × â™‚C. formosanus, ♀C. gestroi × â™‚C. formosanus, ♀C. formosanus × â™‚C. gestroi) in glass screw-top jars placed in incubators at 10, 15, 22, 28, and 35°C in constant darkness for 28 d. Results showed that hybrid termites have a temperature tolerance covering those of both parental species and survived at 15-35°C. WCR was not significantly different among the four mating types, but the WCR in the temperature range of 22-35°C was significantly higher than at temperatures ranging from 10 to 15°C for all mating types. Our results suggest that the potential distribution of the hybrid populations may cover most of the range of both parental species, i.e., 32.5°N and 23.5°S, and they can be as damaging as their parental species, the two most destructive termite pests, C. formosanus and C. gestroi.

Short-Term Evaluation of Left Ventricular Mass and Function in Children With Growth Hormone Deficiency After Replacement Treatment.

Background: Our study was designed to assess the effects of GHD on nutritional and metabolic parameters, brain natriuretic peptide (BNP) levels, and left ventricular mass (LVM) in prepubertal children and after short-term GH replacement therapy. Materials and Methods: This prospective study enrolled 81 children. We compared 40 GHD children (16 males and 24 females) to 41 healthy children (control group) (18 males and 23 females). All subjects were at Tanner Stage I (aged 7-11 years). At the baseline, a blood sample was drawn and echocardiographic images were obtained. These tests were repeated on the GHD subjects after 6 months of GH replacement therapy. Body surface, weight, size, blood pressure, heart rate, glucose, insulin, HOMA-IR, HOMA-ß, QUICKI, cholesterol, HDLc, LDLc, triglycerides, IGF1, and IGFBP3 were measured. Indexed LVM, diastolic and systolic diameter (dD-sD), diastolic and systolic LV function, isovolumic relaxation time, right ventricle function, and BNP levels were obtained through echocardiography. These parameters were correlated to growth factors. Data were analyzed using Student's t-test or U-Mann-Whitney-test and Pearson's correlation, considering p < 0.05 to be significant. Results: Indexed LVM was smaller in GHD patients than in controls, whereas diastolic and systolic functions, BNP, metabolic, and nutritional profiles were similar. After treatment, nutritional and metabolic profiles significantly improved, though diastolic and systolic functions did not seem to have changed. There was a significant increase in LVM. Indexed LVM was similar to that of controls. Significant correlations were obtained between LVM-IGF1 and sD-IGFBP3. Conclusions: GHD in childhood is associated with a lower indexed LVM. In the short-term, GH increases the indexed LVM, while maintaining normal systolic and diastolic functions, BNP, and an improved lipid profile.

Roadside Survey of Ants on Oahu, Hawaii.

Hawaii is home to over 60 ant species, including five of the six most damaging invasive ants. Although there have been many surveys of ants in Hawaii, the last island-wide hand-collection survey of ants on Oahu was conducted in 1988-1994. In 2012, a timed hand-collection of ants was made at 44 sites in a systematic, roadside survey throughout Oahu. Ants were identified and species distribution in relation to elevation, precipitation and soil type was analyzed. To assess possible convenience sampling bias, 15 additional sites were sampled further from roads to compare with the samples near roads. Twenty-four species of ants were found and mapped; Pheidole megacephala (F.), Ochetellus glaber (Mayr), and Technomyrmex difficilis Forel were the most frequently encountered ants. For six ant species, a logistic regression was performed with elevation, average annual precipitation, and soil order as explanatory variables. O. glaber was found in areas with lower precipitation around Oahu. Paratrechina longicornis (Latrielle) and Tetramorium simillimum (Smith, F.) were found more often in lower elevations and in areas with the Mollisol soil order. Elevation, precipitation, and soil type were not significant sources of variation for P. megacephala, Plagiolepis alluaudi Emery, and T. difficilis. P. megacephala was associated with fewer mean numbers of ants where it occurred. Ant assemblages near and far from roads did not significantly differ. Many species of ants remain established on Oahu, and recent invaders are spreading throughout the island. Mapping ant distributions contributes to continued documentation and understanding of these pests.

Termite Species Distribution and Flight Periods on Oahu, Hawaii.

Termites are economically-important structural pests, costing residents of Hawaii over $100 million annually. On Oahu, the last published termite swarming survey occurred from 1969 to 1971, and the last termite hand-collection survey occurred from 1998 to 2000. To contribute data on termite occurrences on Oahu, a light-trap survey took place from February 2011 to September 2012, and a hand-collection survey occurred from September to November 2012. Formosan subterranean termite, Coptotermes formosanus Shiraki, swarming was compared over the duration of the study, finding peak swarming in May 2011. C. formosanus alate activity density was regressed with environmental factors, finding a negative correlation with average wind speed and a positive correlation with average rainfall. Coptotermes gestroi (Wasmann) alates were observed in April, June, and July 2011 and in June 2012. Four species of termites were found in the hand-collection survey of 44 sites: Incisitermes immigrans (Snyder) (n = 8/44), C. formosanus (n = 2/44), Cryptotermes cynocephalus Light (n = 1/44), and Neotermes sp. (n = 1/44). This study contributes to distribution data for termite species on Oahu and records alate activity for two important termite pests.

[Demographic characteristics, malaria chemoprophylaxis and vaccination in 6,783 international travelers attended in a specialized unit]. / Características demográficas, quimioprofilaxis antimalárica e inmunoprofilaxis en 6.783 viajeros internacionales atendidos en una unidad monográfica.

OBJECTIVE: The objective of this paper was to determine the demographic characteristics and the evolution of international travelers treated at the Unit of Infectious and Tropical Medicine in order to improve precautions prior to travel and, thus reduce the occurrence of these diseases. METHODS: A retrospective study of all international travelers served in UEIMT (Las Palmas de Gran Canaria) during the period 1998-2013 was performed. The following variables were collected using a standardized protocol were analyzed: age, gender, date of consultation, type of traveler, countries of destination and preventive measures undertaken (malaria chemoprophylaxis and vaccines). RESULTS: A total of 6,783 international travelers of which 52% were women were analyzed. The average age was 36 years (SD 13). The most frequent destination continent was Africa (39%) followed by Asia (36%) and Latin America (23%). The most common country of destination was India 13% (882), followed by Senegal 7.5% (509) and Thailand 6.3% (429). The most frequently recommended vaccines were typhoid fever (82.9%) and hepatitis A (66.9%). As for malaria prophylaxis, the indicated drugs were atovaquone-proguanil (56.5%), mefloquine (36.7%), in regard to travelers returning to visit relatives and friends with a 26.81% were children (0-9 years).. CONCLUSIONS: The overall profile of the traveler is a young man who chooses holiday destination Africa followed by Asia and Latin America. Over 50% of travelers received vaccination against typhoid and hepatitis A. The most commonly used malaria chemoprophylaxis was atovaquone / proguanil followed by mefloquine.

Accuracy in Rietveld quantitative phase analysis: a comparative study of strictly monochromatic Mo and Cu radiations.

This study reports 78 Rietveld quantitative phase analyses using Cu Kα1, Mo Kα1 and synchrotron radiations. Synchrotron powder diffraction has been used to validate the most challenging analyses. From the results for three series with increasing contents of an analyte (an inorganic crystalline phase, an organic crystalline phase and a glass), it is inferred that Rietveld analyses from high-energy Mo Kα1 radiation have slightly better accuracies than those obtained from Cu Kα1 radiation. This behaviour has been established from the results of the calibration graphics obtained through the spiking method and also from Kullback-Leibler distance statistic studies. This outcome is explained, in spite of the lower diffraction power for Mo radiation when compared to Cu radiation, as arising because of the larger volume tested with Mo and also because higher energy allows one to record patterns with fewer systematic errors. The limit of detection (LoD) and limit of quantification (LoQ) have also been established for the studied series. For similar recording times, the LoDs in Cu patterns, ∼0.2 wt%, are slightly lower than those derived from Mo patterns, ∼0.3 wt%. The LoQ for a well crystallized inorganic phase using laboratory powder diffraction was established to be close to 0.10 wt% in stable fits with good precision. However, the accuracy of these analyses was poor with relative errors near to 100%. Only contents higher than 1.0 wt% yielded analyses with relative errors lower than 20%.

Characterization of the microbial diversity in yacon spontaneous fermentation at 20 °C.

The prebiotic fructooligosaccharide content of yacon makes this root an attractive alternative for the supplementation of a variety of food products. The preservation of yacon by fermentation has been proposed as an alternative to increase the probiotic content of the root concomitantly with its shelf life. Thus the fermented yacon could have significant functional content. The objective of this research was to characterize the biochemistry and microbiology of spontaneous yacon fermentation with 2% NaCl and define the viability of the proposed process. The biochemical analysis of spontaneous heterolactic fermentation of yacon showed a progressive drop in pH with increased lactic and acetic acids, and the production of mannitol during fermentation. The microbial ecology of yacon fermentation was investigated using culture-dependent and culture-independent methods. Bacterial cell counts revealed a dominance of lactic acid bacteria (LAB) over yeasts, which were also present during the first 2 days of the fermentation. Results showed that the heterofermentative LAB were primarily Leuconostoc species, thus it presents a viable method to achieve long term preservation of this root.

A cellular and molecular basis for the selective desmopressin-induced ACTH release in Cushing disease patients: key role of AVPR1b receptor and potential therapeutic implications.

CONTEXT: Desmopressin is a synthetic agonist of vasopressin receptors (AVPRs). The desmopressin stimulation test is used in the diagnosis and postsurgery prognosis of Cushing disease (CD). However, the cellular and molecular mechanisms underlying the desmopressin-induced ACTH increase in patients with CD are poorly understood. OBJECTIVE: The objectives of this study were to determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release and to elucidate the cellular and molecular mechanisms involved in desmopressin-induced ACTH increase in CD. DESIGN: A total of 8 normal pituitaries (NPs), 23 corticotropinomas, 14 nonfunctioning pituitary adenomas, 17 somatotropinomas, and 3 prolactinomas were analyzed for AVPR expression by quantitative real-time RT-PCR. Primary cultures derived from corticotropinomas, nonfunctioning pituitary adenomas, somatotropinomas, prolactinomas, and NPs were treated with desmopressin, and ACTH secretion/expression, [Ca(2+)]i kinetics, and AVPR expression and/or proliferative response were evaluated. The relationship between AVPR expression and plasma adrenocorticotropin/cortisol levels obtained from desmopressin tests was assessed. RESULTS: Desmopressin affects all functional parameters evaluated in corticotropinoma cells but not in NPs or other pituitary adenomas cells. These effects might be due to the dramatic elevation of AVPR1b expression levels found in corticotropinomas. In line with this notion, the use of an AVPR1b antagonist completely blocked desmopressin stimulatory effects. Remarkably, only AVPR1b expression was positively correlated with elevated plasma adrenocorticotropin levels in corticotropinomas. CONCLUSIONS: The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and postsurgery prognosis of CD. Furthermore, our data indicate that AVPR1b is responsible for the direct/exclusive desmopressin stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b antagonists as potential therapeutic tools for CD treatment.

La insuficiencia venosa crónica en el Sistema Nacional de Salud. Diagnóstico, indicaciones quirúrgicas y priorización de listas de espera. Documento de la Sociedad Española de Angiología y Cirugía Vascular (SEACV) y del Capítulo de Flebología y Linfología de la SEACV / Chronic venous insufficiency in the National Health System. Diagnosis, surgical indications and waiting list priorities. A document from the Spanish Association of Angiology and Vascular Surgery (SEACV) and the SEACV Phlebology Chapter

En un entorno de recursos limitados y de crisis, es importante clarificar las indicaciones absolutas y relativas de la cirugía de las varices para garantizar dicha prestación dentro del Sistema Nacional de Salud (SNS) en los casos necesarios y con los máximos criterios científicos disponibles. La Sociedad Española de Angiología y Cirugía Vascular (SEACV), como depositaria de la representatividad profesional, científica y/o técnica de todos sus socios en relación con las administraciones sanitarias, está obligada a estudiar y analizar las necesidades actuales y/o futuras que se presenten en la población de su ámbito, con respecto a la demanda de la especialidad. Presentamos un documento oficial de la SEACV y de su Capítulo Español de Flebología y Linfología (CEFyL) que sienta las bases científicas de la patología venosa y los criterios a tener en cuenta en el momento de valorar su aplicación futura en el SNS(AU)

In an environment with limited resources and a crisis, it is important to clarify the absolute and relative surgical indications of varicose veins, in order to guarantee this service within the National Health System in necessary cases, and with the maximum scientific criteria available. The Spanish Association of Angiology and Vascular Surgery (SEACV,), as the office that represents the professional, scientific and/or technical aspects of all its members with the Health Administrations, is obliged to study and analyse the current and future needs of the population in its area, as regards the demands of the Specialty. We present an official document by SEACV and its Spanish Chapter of Phlebology and Lymphology (CEFandL) that sets the scientific basis of venous pathology and the criteria to take into account when assessing its future application with the National Health System(AU)

Diagnostic assessment to estimate and minimize neutron dose rates received by occupationally exposed individuals at cyclotron facilities.

Since 2003, radiopharmaceuticals for medical diagnostic purposes have been produced at the Instituto de Engenharia Nuclear, in Brazil, using two cyclotron accelerators - CV-28 and RDS111. As a result of the ever increasing production, a diagnostic assessment to reduce neutron dose rates received by occupationally exposed individuals during irradiation processes has been developed. The purpose of this work is to present this assessment, which is currently being applied to both the Fluorine and Iodine targets of CV-28 and RDS111 cyclotron accelerators.

[Postsurgical meningitis. Differential characteristics of aseptic postsurgical meningitis]. / Meningitis postquirúrgica. Características diferenciales de la meningitis aséptica post-quirúrgica.

BACKGROUND: Postsurgical meningitis is a rare complication that is accompanied by an increase of hospital stay and high mortality. Some of these cases are not due to a true infection but due to an aseptic inflammation of the meninges denominated aseptic postsurgical meningitis (APSM). Proper identification of these cases would allow better use of antimicrobial drugs. METHODS: A retrospective study of patients with postsurgical meningitis in a universitary hospital for 14 years. We describe the clinical characteristics of patients with postsurgical bacterial meningitis (PBM) compared to those of patients with APSM. RESULTS: During the studied period 35 patients (71%) with PBM and 14 patients (29%) with (APSM) were identified. The mean age of patients with PBM was similar to that of patients with APSM. There was a male predominance in the group of PBM (71%) compared with patients with APSM (36%, p = 0.020). Patients with intracranial hemorrhage tended to present more cases of APSM (64%) than of PBM (34%, p = 0.055). Patients undergoing posterior fossa craniotomy (p = 0.092) and those receiving steroids (p = 0.051) showed a greater tendency to suffer APSM. It was also noted a trend towards present PBM in patients who had suffered an infection in the previous month (p = 0.072). There were seven patients with PBM (20%) with a cell count above 5000 cells/mm3 in CSF, values not found in any patients with APSM. No differences were detected in the glycorrachia and proteinorrachia between the two groups. The most common bacteria isolated were coagulase negative Staphylococcus and S. aureus. In 5 patients (14%) non fermenting gram-negative bacillus (Pseudomonas aeruginosa and Acinetobacter spp) were isolated. There were no deaths attributed to any type of postsurgical meningitis. CONCLUSION: Patients admitted for brain haemorrhage, undergoing posterior fossa surgery or receiving steroids tend to develop APSM. A CSF cell count above 5000 cells / mm3 strongly suggests MBP.