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Gastrointestinal helminth-microbiota associations are shaped by various ecological processes. The effect of the ecological context of the host on the bacterial microbiome and gastrointestinal helminth parasites has been tested in a number of ecosystems and experimentally. This study takes the important step to look at these two groups at the same time and to start to examine how these communities interact in a changing host environment. Fresh faecal samples (N = 335) from eight wild Eulemur populations were collected over 2 years across Madagascar. We used 16S ribosomal RNA gene sequencing to characterise the bacterial microbiota composition, and faecal flotation to isolate and morphologically identify nematode eggs. Infections with nematodes of the genera Callistoura and Lemuricola occurred in all lemur populations. Seasonality significantly contributed to the observed variation in microbiota composition, especially in the dry deciduous forest. Microbial richness and Lemuricola spp. infection prevalence were highest in a previously intensely logged site, whereas Callistoura spp. showed no such pattern. In addition, we observed significant correlations between gastrointestinal parasites and bacterial microbiota composition in these lemurs, with 0.4-0.7% of the variation in faecal bacterial microbiota composition being explained by helminth infections. With this study, we show effects of environmental conditions on gastrointestinal nematodes and bacterial interactions in wild lemurs and believe it is essential to consider the potential role of microbiome-parasite associations on the hosts' GI stability, health, and survival.

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BACKGROUND: Laying hens with access to outdoor ranges are exposed to additional environmental factors and microorganisms, including potential pathogens. Differences in composition of the cloacal microbial community between indoor- and outdoor-housed layers may serve as an indicator for exposure to the outdoor environment, including its pathogens, and may yield insights into factors affecting the chickens' microbiota community dynamics. However, little is known about the influence of outdoor housing on microbiota community composition in commercial layer flocks. We performed a cross-sectional field study to evaluate differences in the cloacal microbiota of indoor- vs outdoor-layers across farms. Eight layer flocks (four indoor, four outdoor) from five commercial poultry farms were sampled. Indoor and outdoor flocks with the same rearing flock of origin, age, and breed were selected. In each flock, cloacal swabs were taken from ten layers, and microbiota were analysed with 16S rRNA gene amplicon sequencing. RESULTS: Housing type (indoor vs outdoor), rearing farm, farm and poultry house within the farm all significantly contributed to bacterial community composition. Poultry house explained most of the variation (20.9%), while housing type only explained 0.2% of the variation in community composition. Bacterial diversity was higher in indoor-layers than in outdoor-layers, and indoor-layers also had more variation in their bacterial community composition. No phyla or genera were found to be differentially abundant between indoor and outdoor poultry houses. One amplicon sequence variant was exclusively present in outdoor-layers across all outdoor poultry houses, and was identified as Dietzia maris. CONCLUSIONS: This study shows that exposure to an outdoor environment is responsible for a relatively small proportion of the community variation in the microbiota of layers. The poultry house, farm, and rearing flock play a much greater role in determining the cloacal microbiota composition of adult laying hens. Overall, measuring differences in cloacal microbiota of layers as an indicator for the level of exposure to potential pathogens and biosecurity seems of limited practical use. To gain more insight into environmental drivers of the gut microbiota, future research should aim at investigating community composition of commercial layer flocks over time.

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Cultural transmission of migratory traditions enables species to deal with their environment based on experiences from earlier generations. Also, it allows a more adequate and rapid response to rapidly changing environments. When individuals break with their migratory traditions, new population structures can emerge that may affect gene flow. Recently, the migratory traditions of the Barnacle Goose Branta leucopsis changed, and new populations differing in migratory distance emerged. Here, we investigate the population genetic structure of the Barnacle Goose to evaluate the consequences of altered migratory traditions. We used a set of 358 single nucleotide polymorphism (SNP) markers to genotype 418 individuals from breeding populations in Greenland, Spitsbergen, Russia, Sweden and the Netherlands, the latter two being newly emerged populations. We used discriminant analysis of principal components, FST , linkage disequilibrium and a comparison of geneflow models using migrate-n to show that there is significant population structure, but that relatively many pairs of SNPs are in linkage disequilibrium, suggesting recent admixture between these populations. Despite the assumed traditions of migration within populations, we also show that genetic exchange occurs between all populations. The newly established nonmigratory population in the Netherlands is characterized by high emigration into other populations, which suggests more exploratory behaviour, possibly as a result of shortened parental care. These results suggest that migratory traditions in populations are subject to change in geese and that such changes have population genetic consequences. We argue that the emergence of nonmigration probably resulted from developmental plasticity.

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Present-day genetic introgression from domestic pigs into European wild boar has been suggested in various studies. However, no hybrids have been identified beyond doubt mainly because available methods were unable to quantify the extent of introgression and rule out natural processes. Genetic introgression from domestic pigs may have far-reaching ecological consequences by altering traits like the reproduction rate or immunology of wild boar. In this study, we demonstrate a novel approach to investigate genetic introgression in a Northwest (NW) European wild boar data set using a genome-wide single nucleotide polymorphism (SNP) assay developed for domestic pigs. We quantified the extent of introgression using allele frequency spectrum analysis, in silico hybridization simulations and genome distribution patterns of introgressed SNPs. Levels of recent introgression in the study area were expected to be low, as pig farming practices are prevailingly intensive and indoors. However, evidence was found for geographically widespread presence of domestic pig SNPs in 10% of analysed wild boar. This was supported by the identification of two different pig mitochondrial DNA haplotypes in three of the identified hybrid wild boar, suggesting that introgression had occurred from multiple sources (pig breeds). In silico hybridization simulations showed that the level of introgression in the identified hybrid wild boar is equivalent to first-generation hybrids until fifth-generation backcrosses with wild boar. The distribution pattern of introgressed SNPs supported these assignments in four of nine hybrids. The other five hybrids are considered advanced-generation hybrids, resulting from interbreeding among hybrid individuals. Three of nine hybrids were genetically associated with a different wild boar population than the one in which they were sampled. This discrepancy suggests that genetic introgression has occurred through the escape or release of an already hybridized farmed wild boar stock. We conclude that genetic introgression from domestic pigs into NW European wild boar populations is more recent and more common than expected and that genome-wide SNP analysis is a promising tool to quantify recent hybridization in free-living populations.

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As part of a program towards the development of novel antibiotics, a convenient method for solid-phase synthesis of the cyclic cationic peptide polymyxin B1 and analogues thereof is described. The methodology, based on cleavage-by-cyclization using Kenner's safety-catch linker, yields crude products with purities ranging from 37-67%. Antibacterial assays revealed that analogues 23-26, in which the (S)-6-methyloctanoic acid moiety is replaced with shorter acyl chains, exhibit distinct antimicrobial activity. The results suggest that the length of the acyl chain is rather critical for antimicrobial activity. On the other hand, substitution of the hydrophobic ring-segment D-Phe-6/Leu-7 in polymyxin B1 with dipeptide mimics (i.e. analogues 27-33) resulted in almost complete loss of antimicrobial activity.

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[structure: see text]. The cyclooctenol derivative 1 can be transformed into the nine-membered ring lactone 3, as well as the amino-containing carbocycles 4 and 5. The corresponding ketone 2 gives access to the conformationally locked azasugar 6.

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A new method is described for generating all-atom protein structures from Calpha-atom information. The method, which combines both local structural trace alignments and comparative side chain modeling with ab initio side chain modeling, makes use of both the virtual-bond and the dipole-path methods. Provided that 3D structures of structurally and functionally related proteins exist, the method presented here is highly suitable for generating all-atom coordinates of partly solved, low-resolution crystal structures. Particularly the active site region can be modeled accurately with this procedure, which enables investigation of the binding modes of different classes of ligands with molecular dynamics simulations. The method is applied to the trace of Streptococcus pneumoniae, in order to construct an all-atom structure of the transpeptidase domain. Since after generation of full coordinates of the transpeptidase domain the structure had been solved to 2.4 A resolution, new X-ray coordinates for the worst modeled loop (residues T370 to M386; 17 out of a total number of 351 residues constituting the transpeptidase domain) were incorporated, as kindly provided by Dr. Dideberg. The structure was relaxed with molecular dynamics simulations and simulated annealing methods. The RMS deviation between the 144 aligned Calpha-atoms and the corresponding ones in the originally solved 3.5 A resolution crystal structure was 0.98. The 351 Calpha-atoms of the whole transpeptidase domain of the final model showed an RMS deviation of 1.58. The Ramachandran plot showed that 79.3% of the residues are in the most favored regions, with only 1.0% occurring in disallowed regions. The model presented here can be used to investigate the three-dimensional influences of mutations around the active site of PBP2x.

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The chemical synthesis of beta-D-GlcpA-(1-->3)-beta-D-GalpNAc-(1-->O)CH2CH = CH2, beta-D-Galp-NAc-(1-->6)-[beta-D-GlcpA-(1-->3)]-beta-D-GalpNAc-(1-- >O)CH2CH = CH2, and beta-D-GlcpA-(1-->3)-beta-D-GalpNAc-(1-->6)-[beta-D-GlcpA-(1 -->3)] -beta-D-GalpNAc-(1-->O)CH2CH = CH2 is described. These oligosaccharides represent fragments of th circulating anodic antigen, secreted by the parasite Schistosoma mansoni in the circulatory system of the host. The applied synthesis strategy includes the preparation of a non-oxidised backbone oligosaccharide, with a levulinoyl group at O-6 of the beta-D-glucose residue. After the selective removal of the levulinoyl group, the obtained hydroxyl functions were converted into carboxyl groups, using pyridinium dichromate and acetic anhydride in dichloromethane, to afford the desired glucuronic-acid-containing oligosaccharides. Subsequently, the allyl glycosides have been elongated with cysteamine to give the corresponding amine-spacer-containing oligosaccharides.

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The modified zinc test is evaluated as a screening instrument in forensic semen identification using the classical acid phosphatase test as a "gold standard" reference. Both tests were applied to vaginal swabs taken from women (n = 456) at varying time periods after sexual intercourse and the corresponding sensitivity and specificity were calculated for both tests separately and for their parallel and serial combination strategies, with the microscopical visualization of sperm as end criterion. The results were submitted to Bayesian calculations and a model was obtained, giving the posterior probabilities of finding or not finding sperm in a microscopical preparate for any possible prior probability. For the largest part of the theoretical sperm prevalence range, negative predictions were more informative than positive ones. With the prior probability of finding spermatozoa set at P = 0.5 (Bayes' postulate of neutral prior probability), the model was applied to a set of 192 pieces of evidentiary material from alleged sexual assaults.

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BACKGROUND: Syphilis remains a major cause of premature birth, fetal and perinatal death, and congenital syphilis in South Africa, despite systematic antenatal screening by rapid plasma reagin and treatment with 2.4 million U of benzathine penicillin G. GOAL: To determine whether one injection of 2.4 million of U of benzathine penicillin G, as recommended by the 1993 Centers for Disease Control and Prevention guidelines, is sufficient treatment for early syphilis during pregnancy. STUDY DESIGN: Outcome of pregnancy was prospectively analyzed after zero to three weekly intramuscular injections of benzathine penicillin G in 180 of 212 human immunodeficiency virus-seronegative black urban women with syphilis in Pretoria, South Africa. RESULTS: One hundred eight women receiving two or three weekly intra-gluteal injections of benzathine penicillin G had a favorable pregnancy outcome. However, after only one injection, lower birth weight, increased immaturity, prematurity, and total preterm birth rate resulted. Total pregnancy loss and perinatal mortality were also increased. After exclusion of patients treated with oral penicillin derivatives and adjustment for the estimated duration of treponemicidal levels at 3 weeks after injection, the perinatal outcome was reanalyzed. Treponemicidal coverage of 3 weeks or less resulted in decreased birth weight (2,748 vs. 3,130 g, P = 0.004) compared with treponemicidal coverage lasting longer than 3 weeks. In addition, the relative risks for prematurity (relative risk [RR], 8.5; 95% confidence interval [CI95], 2.5-28), perinatal mortality (RR, 20.5; CI95, 2.3-184), and congenital syphilis (RR 2.0; CI95-0.6-6.8) were increased when coverage was less then 3 weeks. These results were comparable to those obtained when no treatment was given. Most of the incompletely treated women delivered at less than 4 weeks after they received their injection. These also had the worst neonatal outcome. Impaired outcome due to short treatment clustered in early attenders of prenatal care (before the 28th week of gestation) and when the initial rapid plasma reagin titer was higher than 16. Although numbers were small for a firm conclusion, incompletely treated and untreated women who had taken intercurrent oral ampicillin had an improved birth weight, lower prematurity rate, and lower fetal rate. CONCLUSIONS: One intramuscular injection of 2.4 million U benzathine penicillin G or treponemicidal concentrations lasting 3 weeks or less is not sufficient therapy for pregnant women with syphilis. Although fetal outcome is clearly improved at birth with more than one injection, without follow-up of the neonates, complete cure cannot be predicted from these data. To obtain treponemicidal activity for longer than 3 weeks, the authors recommend administration of two injections of 2.4 million U benzathine penicillin at least 1 week apart, if possible at 4 weeks or more before delivery. This therapy is especially important for patients who attend prenatal care before 28 weeks of pregnancy or when the rapid plasma reagin titer is higher than 16.

PIP: To determine whether the US Centers for Disease Control guideline of 1 injection of 2.4 million U of benzathine penicillin G is sufficient treatment for early syphilis in pregnant women, this regimen was tested in 180 human immunodeficiency virus-negative urban Black women with syphilis presenting to Kalafong Hospital in Pretoria, South Africa, during 1988-90. A favorable pregnancy outcome was recorded in 108 women who received 2 or 3 weekly intragluteal injections. On the other hand, 1 injection was associated with lower birth weight, increased prematurity and total preterm birth rate, and increased total pregnancy loss and neonatal mortality. These outcomes were reanalyzed after exclusion of women treated with oral penicillin derivatives and adjusted for the estimated duration of treponemicidal levels at 3 weeks post-injection. Birth weight was significantly lower for treponemicidal coverage of 3 weeks or less compared to coverage lasting more than 3 weeks (2748 and 3130 grams, respectively). Also increased when coverage was less than 3 weeks were the relative risks for prematurity (8.5), perinatal mortality (20.5), and congenital syphilis (2.0). Impaired outcome associated with short treatment was clustered in women who attended prenatal care before the 28th week of gestation and those whose initial rapid plasma reagin titer exceeded 16. These findings indicate that the standard protocol is not adequate in areas where syphilis is endemic. Recommended is administration of 2 injections of 2.4 million U benzathine penicillin at least 1 week apart, preferably 4 weeks or more before delivery.

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We conducted a 25-week study of the emergency department's (ED) walk-in patients at a university hospital, covering 20% of the total period by a Latin square method of 6-h blocks. One thousand eight hundred walk-in patients entered the study group. The walk-in population represents approximately 44% of the total ED population. Our results reveal that the study population was predominantly male, aged less than 40 years but somewhat younger than the general population and had a relatively stable place of abode. Trauma and medical patients were respectively 46% and 53%. Eight-six per cent of the trauma patients came to the ED on their own initiative and less than 3 h after the accident or injury, while 43% of the medical patients were referred by a medical practitioner and had a relatively longer duration of symptoms. Forty-eight per cent of the medical patients visited the ED 12 h after the onset of symptoms. Although this study only concerned ED walk-in patients, the admission rate of medical patients is relatively high: 47% as opposed to the trauma patients' 10%. About 10% of the walk-in patients were classified as 'symptoms, signs and ill-defined conditions' according to the International Classification of Diseases 9. Fifty-two per cent of these patients were discharged home. This group of patients requires further investigation.

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A random series of 1,000 parturients in 2 maternity wards in Kinshasa in 1992 were studied. Several parameters affecting birthweight were measured. The predictive value of the Quetelet index, determined by Spearman correlation, was greater than the predictive value of skin folds, brachial circumference, adipose and muscular surfaces or fat mass and was slightly better than lean mass. Anthropometric measurements have certain inconvenience and other factors affect birthweight. These results suggest that the Quetelet index is a sufficiently precise tool for evaluating nutritional state. In addition, its use would allow more time for patient counselling. The longer doctor-patient dialogue could have an effect on prevention in the area of psycho-social stress. This latter factor, combined with the cumulated stress score, was found to be one of the 3 main factors in multiple linear regression evaluation of birthweights reported here.

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The modified qualitative zinc test and the qualitative acid phosphatase test were applied to a total of 1774 semen-free stains made from human body products (n = 575), food products (n = 801), beverages (n = 146), water (n = 120) and other products from daily life (n = 132), in order to assess the degree of interference of these products with the preliminary screening for semen. The zinc test gave positive results in, respectively, 2.4, 3.1, 1.4, 14.1 and 23.5% of the samples, whereas the acid phosphatase test was positive in 3, 3.3, 0, 1.7 and 0% of the samples. Given the large number of positive test results found for products which eventually may be present in stains from alleged sexual assaults, it is concluded that positive screening test results should be interpreted with great caution.

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A 26-year-old man died from severe brain contusion after falling from a moving car during an attempt at car-surfing. Toxicological urine screening was positive for amphetamines, the blood analysis revealed a MDMA level of 0.63 mg/l and a blood alcohol concentration of 1.23 g/l. The case is another example of the bizarre and reckless behaviour which may result from the euphorogenic activity of ecstasy and the circumstances in which it is commonly used.

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Papanicolaou (Pap) smears taken at the first antenatal visit of black African women were examined for lactobacillary expression and its correlation with the prevalence of genital infections and with the outcome of pregnancy. Lactobacillary morphotypes were absent (grade III) in 52% of 256 women. Trichomonas, Chlamydia, gonococci, or syphilis was identified in 54% of grade III women, and in 17% of grade I + II women (p < 0.0001). There were partially independent positive associations of Trichomonas, Chlamydia, and gonococci and a negative association of Candida morphotypes with grade III. Absence of lactobacilli, whether or not in the context of bacterial vaginosis, is an indicator for the presence of other genital infections. Birthweight was 2000 gm or less in 5% of 82 children of grade I + II mothers, and in 16% of 83 children of grade III mothers (p = 0.02). Thus, there are populations in whom the grading of lactobacilli in routine Pap smears helps to direct further investigations and to predict the outcome of pregnancy.

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STUDY OBJECTIVE: The aim was to assess the differences in suicide data obtained from different database sources. DESIGN: Death certificate based data on suicidal deaths were compared with the information obtained from the non-natural death investigation files at the Public Prosecutor's Office. SETTING: The study was confined to the time period of 1981-1984 and to the residents of the district of Leuven (Belgium) who died in the district. MAIN RESULTS: Differences were found in the number of suicidal deaths reported as well as in the demographic variables, the distribution of suicide methods, and the place of death. Sixty percent of the records in both databases could be matched for all variables studied (age, gender, civil state, place of death, and suicide method), and another 10% if only place of death was allowed to differ. For 4.5% of the cases in the judicial files and for 8% of the records in the official statistics database no corresponding record from the other data source could be found. Based on simple probability statistics [P(missing record)+P(different information[present)] the possible minimum global information bias could be estimated to range from 7 to 42%. CONCLUSIONS: Different epidemiological pictures of suicide mortality may result from studying different data sources.

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A more sensitive modification of the zinc test for semen has been developed, which can be used either as a solution or incorporated into test papers. The latter retain their sensitivity for at least 3 months.

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The modified zinc test and a commercially available acid phosphatase test were compared as to their screening parameters according to the microscopical finding of spermatozoa in cases of alleged sexual assault. The study involved 65 pieces of evidence material. It was found that the modified zinc test has a higher sensitivity and higher predictive values than the acid phosphatase test. However, when both tests are combined in parallel, the sensitivity and the negative predictive value could be raised to 99%. This finding suggests that a negative result obtained from the parallel combination of the modified zinc test and the acid phosphatase test predicts very well that no spermatozoa will be found at microscopical examination. Since the latter technique is the only one to give absolute proof of the seminal origin of stains or traces, the parallel combination of the zinc test and the acid phosphatase test might be useful in sorting out these cases or materials that deserve further investigation by more elaborate techniques.

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In a prospective study of 124 urban black pregnant women, 43% had Candida isolated from endocervical cultures and 20% had Candida cell forms on cytological Pap-stained cervical specimens. The presence of Candida cell forms on Pap smears had a better correlation with Candida colonisation when normal lactobacillary flora was present, when Trichomonas vaginalis parasites were absent and when the infecting Candida species was C. albicans. Positive cultures were strongly related to a number of clinical signs and symptoms, but Pap smears were not. Neither Candida culture nor Candida cells in Pap smear revealed an association with premature delivery, birth weight, severe neonatal morbidity or mortality. We confirm that the routine cervical Pap smear is not a sensitive method for diagnosing symptomatic fungal infection. More specifically, some of the Pap smear characteristics, such as disturbed lactobacillary flora or co-infection with T. vaginalis, interfere with accurate diagnosis.

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The gram-negative aerobic oral bacterial flora of 100 consecutive corpses was isolated. After the identification and culturing of the isolated organisms, blood grouping was performed by the haemagglutination inhibition technique on dried culture smears, the dried culture medium and a dried ethanol extract of the bacteria. Forty-seven of the samples showed a gram-negative aerobic bacterial growth, giving 58 microorganisms of 14 different species. Positive blood grouping results were found in two of them (Escherichia coli and Serratia marcescens), both of type B. It is concluded that occasional mistyping of blood groups on saliva and oral material may be caused by the oral gram-negative aerobic flora, especially if the specimens are contaminated or putrefying.

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