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Phage types and ribotypes of Salmonella enteritidis in southern Italy.

Differently from other European countries, Southern Italy was affected by a considerable increase in human infections due to Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) only after 1990. On the present investigation, two groups of S. Enteritidis strains isolated during the low-incidence period 1980-1984 and the epidemic period 1990-1993, respectively, have been submitted to phage-typing and ribotyping in order to ascertain whether the epidemic increase was determined by the spread of a foreign bacterial clone or not. Among the 150 isolates relative to the aforesaid two periods, 12 different phage types (PTs) were observed. PT4 was the most common phage type among the strains isolated in 1980-1984 (61%) as well as in those of the epidemic period 1990-1993 (72%). PT8 was the second most frequent (33%) phage type in 1980-1984. It was substituted by PT1 (19%) in the 1990-1993 period. Analysis of rDNA patterns obtained after Hinc II digestions and Escherichia coli rRNA hybridizations showed 8 different patterns, A to H. The great majority of the strains studied (140 isolates, 93%) belonged to the ribotype A, showing a similar frequency both in 1980-1984 (36 of 39, 92%) and in 19901993 (104 of 111, 94%). The predominance of PT4 and ribotype A among both preepidemic and epidemic strains is in agreement with the hypothesis that host genetic diversity decline and modern farming practices in the poultry industry have facilitated a widespread dissemination of preexisting endemic strains. This hypothesis urges to plan new strategies in preventing S. Enteritidis infections.

Bacterial Typing Techniques↗

Microbial analyses by fluorescence in situ hybridization of well-settled granular sludge in brewery wastewater treatment plants.

The characteristics of granular sludge from full-scale upflow anaerobic sludge blanket reactors used for the treatment of brewery wastewater were investigated. Fluorescence in situ hybridization (FISH) analyses of settled granules from a reactor that had been treating brewery wastewater stably at COD removal rates of over 90% for more than 6 months showed that a methanogen of the genus Methanosaeta was predominant near the granule surface and that Bacteria were not abundant. The center of the granules was composed of dead or resting cells, or both, which were used as a support for active archaeal and bacterial cells near the surface. Periodic analysis of granules from full-scale plants showed that granules containing methanogens deep within them tended to float. Granules with a Bacteria layer on the surface also tended to float. On the basis of these findings, well-settled granules are considered to have methanogens that develop near the granule surface so that the gases generated during methane fermentation are readily released.

Journal Article↗

The spliced leader RNA gene array in phloem-restricted plant trypanosomatids (Phytomonas) partitions into two major groupings: epidemiological implications.

The arbitrary genus Phytomonas includes a biologically diverse group of kinetoplastids that live in a wide variety of plant environments. To understand better the subdivisions within the phytomonads and the variability within groups, the exon, intron and non-transcribed spacer sequences of the spliced leader RNA gene were compared among isolates of the phloem-restricted members. A total of 29 isolates associated with disease in coconut, oil palm and red ginger (Alpinia purpurata, Zingibreaceae) were examined, all originating from plantations in South America and the Caribbean over a 12-year period. Analysis of non-transcribed spacer sequences revealed 2 main groups, I and II; group II could be further subdivided into 2 subgroups, IIa and Ilb. Three classes of spliced leader (SL) RNA gene were seen, with SLI corresponding to group I, SLIIa to group lIa, and SLIIb to group IIb. Two isolates showed some characteristics of both major groups. Group-specific oligonucleotide probes for hybridization studies were tested, and a multiplex amplification scheme was devised to allow direct differentiation between the 2 major groups of phloem-restricted Phytomonas. These results provide tools for diagnostic and molecular epidemiology of plant trypanosomes that are pathogenic for commercially important flowers and palms.

Animals↗

Prediction of outcome in neurotic disorder: a 5-year prospective study.

BACKGROUND: There have been no previous studies of the outcome of different neurotic disorders in which a prospective group with original randomization to treatment have been followed up over a long period. Such studies are important in identifying the factors associated with good and poor outcome. METHODS: A 5-year follow-up assessment was made of a cohort of 210 psychiatric out-patients seen in general practice psychiatric clinics with a DSM-III diagnosis of generalized anxiety disorder (71), panic disorder (74) or dysthymic disorder (65) and randomized to drug treatment, cognitive and behaviour therapy, and self-help. A total of 182 of the patients (87%) were assessed after 5 years by examination of hospital and GP records using a standardized procedure and outcome determined with a four-point outcome scale. RESULTS: One hundred and seven (60%) of the patients had a favourable outcome but the remainder continued to be handicapped either intermittently or continuously throughout the 5-year period. Analysis of the value of initial data in predicting outcome using polychotomous step-wise logistic regression revealed that five variables were significant predictors of poor prognosis: older age; recurrent episodes; the presence of personality disorder at entry; general neurotic syndrome at entry; and symptom severity after 10 weeks. The initial DSM diagnosis and original treatment given, together with ten other variables, were of no predictive value. CONCLUSIONS: The long-term outcome of neurotic disorder is better predicted by age, personality and recency of onset than by other clinical variables with the exception of initial response to treatment.

Adult↗

Structure of the complex group-specific polysaccharide of group B Streptococcus.

The group-specific antigen was isolated from a type Ia group B streptococcal strain and is a complex polysaccharide composed of alpha-L-rhamnopyranosyl, alpha-D-galactopyranosyl, 2-acetamido-2-deoxy-beta-D-glucopyranosyl, D-glucitol, and phosphate residues. The complexity of the group B polysaccharide antigen is evident from the fact that when depolymerized by basic hydrolysis it yielded three structurally related, but nevertheless significantly different, oligosaccharides. These oligosaccharides were obtained in different molar quantities as their monophosphate esters. This evidence strongly suggests that they are linked by phosphodiester bonds in the original group B antigen. If these oligosaccharides are in fact randomly situated throughout the linear polysaccharide, then this type of heterogeneous repeating unit is unusual for a polysaccharide of bacterial origin. However, this structural arrangement of the oligosaccharides has yet to be unambiguously established because the alternate explanation of there being three different polysaccharides in the group B antigen cannot be discounted in the evidence presented here. The oligosaccharides were enzymatically dephosphorylated, and the structures of two of the three oligosaccharides are (formula: see text) Despite their structural differences, the two oligosaccharides are related by the smaller being an integral part of the larger. In the structural analysis of the group B antigen, methylation analysis, periodate oxidation, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, fast atom bombardment mass spectrometry, and various specific chemical and enzymatic degradations were the principal methods used. Of particular interest was the use of an alpha-rhamnosidase to selectively degrade the larger oligosaccharide. This facilitated the assignment of signals in its 1H and 13C NMR spectra.

Carbohydrate Conformation↗

Structural analysis of the specific capsular polysaccharide of Streptococcus pneumoniae type 45 (American type 72).

The specific capsular polysaccharide of Streptococcus pneumoniae type 45 (American type 72) was found to be a high molecular weight polymer composed of D-galactose, 2-acetamido-2-deoxy-D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-L-fucose, L-rhamnose, glycerol, and phosphate (2:1:1:1:1:1:1). Partial hydrolysis, dephosphorylation, methylation analysis, periodate oxidation studies, and one- and two-dimensional 1H and 13C high-field nuclear magnetic resonance experiments showed the polysaccharide to be a branched polymer of a 1-phosphoglycerol-substituted hexasaccharide repeating unit having the structure: (formula; see text).

Carbohydrate Sequence↗

Tryptophan scanning mutagenesis in the TM3 domain of the Torpedo californica acetylcholine receptor beta subunit reveals an alpha-helical structure.

We used tryptophan substitutions to characterize the beta M3 transmembrane domain (betaTM3) of the acetylcholine receptor (AChR). We generated 15 mutants with tryptophan substitutions within the betaTM3 domain, between residues R282W and I296W. The various mutants were injected into Xenopus oocytes, and expression levels were measured by [125I]-alpha-bungarotoxin binding. Expression levels of the M288W, I289W, L290W, and F293W mutants were similar to that of wild type, whereas the other mutants (R282W, Y283W, L284W, F286W, I287W, V291W, A292W, S294W, V295W, and I296W) were expressed at much lower levels than that of wild type. None of these tryptophan mutants produced peak currents larger than that of wild type. Five of the mutants, L284W, F286W, I287W, V295W, and I296W, were expressed at levels <15% of the wild type. I296W had the lowest expression levels and did not display any significant ACh-induced current, suggesting that this position is important for the function and assembly of the AChR. Tryptophan substitution at three positions, L284, V291, and A292, dramatically inhibited AChR assembly and function. A periodicity analysis of the alterations in AChR expression at positions 282-296 of the betaTM3 domain was consistent with an alpha-helical structure. Residues known to be exposed to the membrane lipids, including R282, M285, I289, and F293, were all found in all the upper phases of the oscillatory pattern. Mutants that were expressed at lower levels are clustered on one side of a proposed alpha-helical structure. These results were incorporated into a structural model for the spatial orientation of the TM3 of the Torpedo californica beta subunit.

Acetylcholine↗

Structural analysis of a neutral (1-->3),(1-->4)-beta-D-glucan from the mycelia of Cordyceps sinensis.

The extracellular polysaccharide (1) extracted from the mycelia of Cordyceps sinensis with hot water was fractionated and purified by ion-exchange and gel-filtration chromatography. The structure was investigated using methylation and hydrolysis analysis, periodate oxidation, NMR spectroscopy, and reaction with beta-D-glucanase, and the results indicated that this D-glucan consisted of a backbone composed of (1-->3)-beta-D-glucosyl residues and carried a single (1-->4)-beta-linked D-glucosyl residue. NMR and IR spectroscopic measurements showed that the sugar residues were beta-glycosidically linked.

China↗

O-specific polysaccharide of the marine bacterium "Alteromonas marinoglutinosa" NCIMB 1770.

The O-specific polysaccharide of the marine bacterium "Alteromonas marinoglutinosa" NCIMB 1770 was obtained by mild acid degradation of the corresponding lipopolysaccharide and found to contain D-galactose, N-acetyl-D-glucosamine, and N-acetyl-D-mannosamine residues in equimolar ratio. Based on methylation analysis, periodate oxidation, and 13C-NMR spectroscopy data of native and modified polysaccharides, the following structure of the trisaccharide repeating unit of the O-specific polysaccharide was established: [structure: see text]

Acetylglucosamine↗

Tuberculosis among health care workers during three recent decades.

Some studies have found that health care workers have an increased risk of tuberculosis, whereas other studies have reported the opposite. This study examined data of Finnish health care workers (HCWs) for the incidence of tuberculosis disease. Cases of occupational tuberculosis in Finland were analysed over a period of 30 yrs (1966-1995). Control subjects were all other incident tuberculosis cases at working age. The material thus obtained included 658 people with notified occupational tuberculosis, and 56,146 control cases. The authors studied incidence, and age specific rate, as well as their trends. The incidence of tuberculosis among health care workers decreased from 57.9 to 6.1 per 100,000 and the corresponding figures among control subjects decreased from 156.8 to 9.1 per 100,000. The overall risk in health care workers was lower than in the general population throughout the study period. Analysis of age specific rates revealed no age group at increased risk. The reasons are multifactorial, among them the successful tuberculosis programme, and the lack of impact of such risk factors as immigration, human immunodeficiency virus infection and drug resistance; high coverage of bacille Calmette-Guérin vaccination may also be a factor, although it is difficult to assess.

Adult↗

The relation of alcohol use to HIV-risk sexual behavior among adults with a severe and persistent mental illness.

The authors examined the relationship between alcohol use and HIV-risk sexual behavior and tested whether alcohol use immediately prior to sex is related to decreased condom use. The participants were 159 adults living with a severe and persistent mental illness. Each participated in a structured interview to assess all sexual and drug-use behavior over a 3-month period. Analysis of 3,026 sexual behaviors reported by 123 sexually active participants indicated that at the global level, participants who drank more heavily were more likely to have engaged in sexual risk behavior. At the event level, however, alcohol use was not related to condom use during vaginal or anal intercourse; that is, participants who used condoms when sober tended to use them to the same extent when drinking.

Adult↗

Climate (communication arising): impact of land-use change on climate.

Urbanization and other changes in land use have an impact on surface-air temperatures. Kalnay and Cai report that the observed surface-temperature trend in part of the United States exceeds the trend in the NCEP/NCAR 50-year reanalysis (NNR) and conclude that changes in land use account for the difference (0.035 degrees C per decade according to their corrected values). Although land-use change may explain some of this discrepancy, the authors do not quantify the impact of the many changes in observational practice that occurred during the analysis period. Our findings indicate that these 'non-climatic' changes have a systematic effect that overwhelms the reported difference in trends and therefore calls Kalnay and Cai's central conclusion into question.

Comment↗

Trends and socioeconomic inequalities in cancer survival in England and Wales up to 2001.

We examined national trends and socioeconomic inequalities in cancer survival in England and Wales during the 1990s, using population-based data on 2.2 million patients who were diagnosed with one of the 20 most common cancers between 1986 and 1999 and followed up to 2001. Patients were assigned to one of five deprivation categories (from 'affluent' to 'deprived') using characteristics of their electoral ward of residence at diagnosis. We estimated relative survival up to 5 years after diagnosis, adjusting separately in each deprivation category for background mortality by age, sex and calendar period. We estimated trends in survival and in the difference in survival between deprivation categories ('deprivation gap') over the periods 1986-90, 1991-95 and 1996-99. We used period analysis to examine likely survival rates in the near future. Survival improved for most cancers in both sexes during the 1990s, and appears likely to continue improving for most cancers in the near future. The deprivation gap in survival between rich and poor was wider for patients diagnosed in the late 1990s than in the late 1980s. Increases in cancer survival in England and Wales during the 1990s are shown to be significantly associated with a widening deprivation gap in survival.

England↗

Replacement of proteoglycans in embryonic chick cartilage in organ culture after treatment with testicular hyaluronidase.

Explants of cartilage from tibiae of 11-12 days chick embryos were grown in organ culture. To one group hyaluronidase was added to the medium during the first 2 days of culture; the treated tissue was then cultured in medium without enzyme for a further 4 days. Control explants grown in hyaluronidase-free medium for 6 days grew rapidly in size and the total hexosamine content more than doubled during this time. After exposure to hyaluronidase, much of the hexosamine was lost from treated cartilage and appeared in the culture medium, but it was mostly replaced in the tissue during the subsequent recovery period. Analysis of cartilage and medium showed that net synthesis of hexosamine increased greatly in treated cartilage. The proteoglycans were extracted by two procedures from control and treated cartilage after 2, 4 and 6 days in culture. The hydrodynamic sizes of the purified proteoglycans were compared by gel chromatography and the composition of the gel-chromatographic fractions was determined. The proteoglycans from controls did not change during culture, but after exposure to hyaluronidase the proteoglycans from treated cartilage were of much smaller size and lower chondroitin sulphate content. During recovery, even though new proteoglycans were formed, they were nevertheless of smaller size and lower chondroitin sulphate content than control proteoglycans. They gradually became more like control proteoglycans during recovery from treatment, but even after 4 days they were not yet the same. After 2 days of treatment with the enzyme, the chondroitin sulphate in the cartilage was of shorter chain length than in controls but during recovery after 4 and 6 days in culture, the chain lengths in control and treated cartilage were similar. It is concluded that the proteoglycans formed in embryo cartilage in response to their depletion by enzyme treatment contained fewer chondroitin sulphate chains attached to the protein moiety of proteoglycans. This may have resulted from a failure under stress to glycosylate the protein moiety to the usual extent; alternatively the synthesis of normal proteoglycans of low chondroitin sulphate content may have increased, thus changing the proteoglycan population.

Animals↗

Structural elucidation of novel phosphocholine-containing glycosylinositol-phosphoceramides in filamentous fungi and their induction of cell death of cultured rice cells.

Novel ZGLs (zwitterionic glycosphingolipids) have been found in and extracted from the mycelia of filamentous fungi ( Acremonium sp.) isolated from soil. Five ZGLs (ZGL1-ZGL5) were structurally elucidated by sugar compositional analysis, methylation analysis, periodate oxidation, matrix-assisted laser-desorption ionization-time-of-flight MS, (1)H-NMR spectroscopy and fast-atom bombardment MS. Their chemical structures were as follows: GlcN(alpha1-2)Ins1-P-1Cer (ZGL1), Man(alpha1-6)GlcN(alpha1-2)Ins1-P-1Cer (ZGL2), Man(alpha1-6)Man(alpha1-6)GlcN(alpha1-2)Ins1-P-1Cer (ZGL3), PC-->6Man(alpha1-6)GlcN(alpha1-2)Ins1- P -1Cer (ZGL4), and PC-->6Man(alpha1-6)Man(alpha1-6)GlcN(alpha1-2)Ins1-P-1Cer (ZGL5) (where Cer is ceramide and PC is phosphocholine). In addition, one acidic glycosphingolipid, which was the precursor of ZGLs, was also characterized as inositol-phosphoceramide. The core structure of the ZGLs, GlcN(alpha1-2)Ins1- P, is rather different from those found in other fungi, such as Man(alpha1-2)Ins1- P and Man(alpha1-6)Ins1- P. Interestingly, the terminal mannose residue of ZGL4 and ZGL5 was modified further with a PC group. The presence of PC-containing glycosylinositol-phosphoceramides has not been reported previously in any organism. The ceramide constituents of both ZGLs and acidic glycosphingolipid were essentially the same, and consisted of a 4-hydroxyoctadecasphinganine (phytosphingosine) as the sole sphingoid base and 2-hydroxytetracosanoic acid (>90%) as the major fatty acid. ZGLs were found to cause cell death in suspensions of cultured rice cells. The cell death-inducing activity of ZGLs is probably due to the characteristic glycan moiety of Man(alpha1-6)GlcN, and PC-containing ZGLs had high activity. This study is the first to demonstrate that fungal glycosylinositol-phosphoceramides induce cell death in cultured rice cells.

Acidic Glycosphingolipids↗

Adenoid cystic carcinoma of the head and neck.

Adenoid cystic carcinoma has a long natural history but frequently proves fatal. The present study describes 108 patients with an adenoid cystic carcinoma of the head and neck seen over a 30-year period. Analysis of the data utilized both univariate and multivariate methods. Forty per cent of patients had tumours arising from the oral cavity and half of these were in the hard palate; 29% occurred in the major salivary glands; 41% of tumours were locally advanced at presentation and 11% had lymph node metastases at this time. The histological pattern was solid in 25%, cribriform in 40% and tubular in 20%. In addition, 15% of patients had a polymorphous low-grade adenocarcinoma and these were analysed separately. Primary site recurrence was more common in the presence of locally advanced tumours at presentation (T3-4) (P = 0.0093). Only six patients had surgery with adjuvant radiotherapy. Six patients had no curative treatment, 21 had primary radiotherapy, 39 had local excision and 42 radical excision. The actuarial primary site recurrence rate was 100% at 30 years. The neck node recurrence rate was 23% at 15 years. Tumour specific survival was 40% at 20 years. Solid histology had a worse prognosis than other histological types (P = 0.0429) but those patients with polymorphous low-grade adenocarcinomas fared very well. Patients with tumours of the hard palate fared better than those patients with tumours at other sites (P = 0.0301). Early disease at the primary site (T1-2) was a good prognostic sign (P = 0.0013). Patients with neck node metastases at presentation tended to do badly (P = 0.009).

Carcinoma, Adenoid Cystic↗

Structural identification of the lipopolysaccharide O-antigen produced by Yersinia enterocolitica serotype O:28.

The structure of the O-antigenic polysaccharide (O-PS) component of the lipopolysaccharide produced by Yersinia enterocolitica serotype O:28 has been elucidated. From chemical methods involving glycose analysis, periodate oxidation, methylation and the use of one- and two-dimensional NMR spectroscopy, the O-PS was found to be a polymer of repeating branched hexasaccharide units composed of L-rhamnose (four parts), 2-acetamido-2-deoxy-D-glucose (one part), and 2-acetamido-2-deoxy-D-galacturonic acid (one part) having the following structure:

Carbohydrate Conformation↗

Effects of microgravity on the larval development, metamorphosis and reproduction of the urodele amphibian Pleurodeles waltl.

The FERTILE experiment was twice performed onboard the Mir space station during the Cassiopée and Pégase French space missions. The goal was to analyze the effects of microgravity on fertilization and embryonic development, and then on further development on the ground in the amphibian Pleurodeles waltl. The present paper reports development that occurred in the laboratory after landing. Recovered on the ground at the hatching stage, young larvae reared at room temperature underwent metamorphosis and became adults without obvious abnormalities. Of particular interest was the rearing temperature that induced a delayed metamorphosis for animals from the Cassiopée space mission, but not for animals from the Pégase mission. The rate of development and the morphology were analogous in these animals and in ground controls reared in a similar annual period. Analysis of offspring was performed using these animals. Males born in space were first mated with control ground-born females and then with females born in space. The mating gave progeny that developed normally. Depending on the methods used and on the limits of the analyses, the results clearly demonstrated that animals born in space were able to live and reproduce after return to the ground.

Animals↗