Development of an ELISA specific for Listeria monocytogenes using a polyclonal antibody raised against a cell extract containing internalin B

We have developed a new enzyme-linked immunosorbent assay (ELISA) that is specific to the foodborne pathogenic micro-organism Listeria monocytogenes. It is based on an antibody raised against an L. monocytogenes cell preparation optimized for extraction of internalin B. Only in a sandwich ELISA format was the protein A-purified antibody specific to L. monocytogenes. In a competitive ELISA format, the antibody recognizes other Listeria species. The sandwich ELISA shows no recognition of L. innocua, L. ivanovii, L. welshimeri, L. seeligeri, or L. grayii. It has a minimum detectable level for L. monocytogenes of log₁₀?6.37 cfu ml^?1 in pure culture, is reproducible, and is unaffected by the presence of high numbers (approximately log₁₀?8.0 cfu ml^?1) of the other Listeria species. Possible reasons for the format-dependent specificity are discussed. When the ELISA was applied to milk samples inoculated with L. monocytogenes reference material (5 cfu ml^?1), there was a strong response to the enrichment cultures. The new assay may prove useful in detection of L. monocytogenes in enrichment cultures of food samples.     

Biochemical characterization of a shikimic acid-resistant mutant of Nostoc linckia

The growth of Nostoc linckia was significantly inhibited by shikimic acid concentrations greater than 4.0 μg ml^?1 and was completely inhibited at 10.0μg ml^?1. Shikimic acid increased the duration of the lag phase and the doubling time and hastened the onset of the retardation phase of growth. A mutant (NL_shi) capable of growing in presence of 50 μg ml^?1 shikimic acid, was isolated by nitrosoguanidine mutagenesis from the wild type population at a frequency of about 1 × 10^?5 to 1 × 10^?6. The mutant grew slower than the wild type. Both the wild type and the mutant strain grew photoheterotrophically in light, with and without 3 (3–4 dichlorophenyl) 1,1-dimethyl urea (DCMU) and in darkness when provided with glucose. Glucose supplementation promoted ammonium uptake from the medium, when wild type and mutant were grown in an ammonium-supplemented medium. Glucose stimulated heterocyst production and nitrogenase activity in both the strains. As compared to wild type, this mutant showed higher heterocyst frequency and nitrate reductase activity but its ammonium uptake activity was lower. No significant difference in glutamine synthetase and nitrogenase activities of the mutant were observed. The mutant was stable and retained its resistance even after several subcultures through medium free of shikimic acid.     

Morphological,toxicological and molecular characterization of a benthic Nodularia isolated from Atlantic estuarine environments

A polyphasic study of a benthic Nodularia isolate (LEGE06071) from an Atlantic environment, specifically salt pans, was performed. LEGE06071 resembled both type strains of Nodularia sphaerocarpa and Nodularia harveyana, while ACOI00729 (purchased isolate) was identified as N. sphaerocarpa. The length and width of vegetative cells varied from 3.10 to 3.15 μm and from 3.71 to 4.25 μm, respectively, while heterocyts were 3.91–4.89 μm long and 4.20–4.74 μm wide. None of the isolates had aerotopes. The sequencing of the 16S rRNA gene from the two Nodularia isolates indicated that they belonged neither to Nodularia spumigena nor N. harveyana. Nodularin and other cyanotoxin synthesis-associated genes could not be detected, nor could nodularin production be detected by ELISA. However, MALDI-TOF analysis of LEGE06071 revealed the presence of other compounds, namely, glycolipids. Hence, toxicological screenings against Artemia nauplii, Escherichia coli and Salmonella typhimurium were performed. Toxic effects could only be observed against Artemia, with 48 h-LC₅₀ values for the aqueous and crude extract of methanol of 53.21 mg ml^?1 and 17.81 mg ml^?1, respectively. This study presents the first evidence of a non-nodularin-producing Nodularia isolate in Atlantic salt pan ecosystems and its potential ecotoxicity against Artemia sp.     

Evaluation of sperm characteristics and plasma testosterone in the goldfish (Carassius auratus) during four consecutive seasons

The overall objective of the study was to investigate changes in quantitative parameters of goldfish (Carassius auratus) semen, testosterone (T), and gonadosomatic index (GSI) during the four seasons of the year (spring, summer, autumn, and winter). Simple environmental and hormonal treatments were used to induce out-of-season spawning in goldfish. The semen was taken from goldfish in different periods during the four seasons, and the characteristics of sperm and pH were analyzed. Plasma levels of T, GSI, and histological studies of the testes, as well as a range of indices of ovarian development, were measured. No significant differences were observed between volumes of semen which can be extracted per fish, in the four seasons (P?>?0.05). Significant differences were found between sperm motility at different seasons (P?<?0.05), as the maximum total duration of motility was observed in autumn (109.25?±?14.00 s). Sperm density showed a higher value during summer (57.30?±?10.41?spermatozoa (spz)?ml^?1) and winter (65.09?±?80.40 spz ml^?1) than values that were obtained from spring (48.00?±?7.08 spz ml^?1) and autumn (40.42?±?16.54?×?10⁹ spz ml^?1) (P?<?0.05). However, spermatocrit (in percent) was higher in winter (39.90?±?4.74) compared with other seasons (P?<?0.05). Values of pH were higher in autumn (7.87?±?0.05) and in winter (7.83?±?0.03) than values that were obtained from other seasons. The peaks of T and GSI during spermiation in spring (T, 21.08 ng/ml, and GSI?=?5.21 %) and in summer (T, 23.32 ng/ml, and GSI?=?6.10 %), when most gonadal development took place, were statistically significantly higher than the levels observed during autumn (T, 15.08 ng/ml, and GSI?=?3.21 %) and winter (T, 22.18 ng/ml, and GSI?=?2.78 %) (P?<?0.05). Our results provided the statistically significant evidence of seasonal variation in sperm characteristics, T and GSI, for goldfish. These findings may be used to: (1) optimize semen collection for hatchery production and (2) characterize the potential impact of seasons on sperm quality and plasma androgen levels.     

Pro- and anti-apoptotic roles for IGF-I in TNF-α-induced apoptosis: A MAP kinase mediated mechanism

Objective. The concept of skeletal muscle homeostasis—often viewed as the net balance between two separate processes, namely protein degradation and protein synthesis—are not occurring independently of each other, but are finely co-ordinated by a web of intricate signalling networks.

Materials and methods. Using rodent muscle cell lines we have investigated TNF-α/IGF-I interactions, in an attempt to mimic and understand mechanisms underlying the wasting process.

Results and conclusion. When myoblast cells are incubated with TNF-α (10 ng ml^{? 1}) maximal damage (～21% ± 0.7 myoblast death, p < 0.05) was induced. Co-incubation of TNF-α (10 ng ml^{? 1}) with IGF-I resulted in cell survival (～50% reduction in myoblast death, p < 0.05), however, myotube formation was not evident. In contrast, a novel role of IGF-I has been identified whereby co-incubation of muscle cells with IGF-I (1.5 ng ml^{? 1}) and a non-apoptotic dose of TNF-α (1.25 ng ml^{? 1}; sufficient to block differentiation) unexpectedly were shown not to rescue a block on differentiation but to facilitate significant myoblast death (p < 0.05). Interestingly, pre-administration of PD98059, a MAPK signal-blocking agent followed by co-incubation of 1.25 ng ml^{? 1} TNF-α and 1.5 ng ml^{? 1} IGF-I, reduced death to baseline levels (p < 0.05). We show for the first time that IGF-I can be apoptotic in the absence of TNF-α-induced cell death.     

Testicular morphology and antispermatogenic effects of 2,4-dichlorophenoxyacetic acid (2,4-D) in male West African Dwarf (WAD) goats

This study investigated the testicular morphology as well as the gonadal and extra-gonadal sperm reserves of West African Dwarf (WAD) goats exposed to graded levels of 2,4-dichlorophenoxyacetic acid (2,4-D). Twenty male WAD goats of five goats per group were used for this study. Goats in groups A, B and C received low [75?mg/kg body weight (BW)], medium (100?mg/kg BW) and high (125?mg/kg BW) dose levels of 2,4-D, respectively. The group D goats served as the control. On day?112, goats in the four groups were sacrificed and the testicular and epididymal sperm reserves were determined. Histopathologic changes in the testis of the 2,4-D-exposed and control goats were also assessed. The mean number of spermatozoa in the testes and the various segments of the epididymides decreased significantly (p?<?0.05) in all the treatment groups relative to the control. Combined testicular sperm reserve per millilitre for the treatment groups (group A—19.61?±?2.63?×?10⁸, group B—12.02?±?1.02?×?10⁸ and group C—9.95?±?0.97?×?10⁸) reduced significantly (p?<?0.05) relative to the mean value (23.52?±?4.43?×?10⁸) of the control—group D. The total epididymal sperm reserve per millilitre in the treatment groups (group A—24.25?±?4.19?×?10⁸, group B—17.18?±?2.57?×?10⁸ and group C—17.88?±?2.89?×?10⁸) was also found to be significantly (p?<?0.05) lower than the mean value (40.85?±?11.24?×?10⁸) for the control—group D. This reduction in the testicular and epididymal sperm counts of the 2,4-D-exposed WAD goats in this study suggest disruption in spermatogenic activity, which may lead to low productivity. Variable degrees of circulatory disturbances were observed in the testis sections of 2,4-D-exposed goats.     

Quantification of Vibrio parahaemolyticus,Vibrio vulnificus and Vibrio cholerae in French Mediterranean coastal lagoons

Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae are human pathogens. Little is known about these Vibrio spp. in the coastal lagoons of France. The purpose of this study was to investigate their incidence in water, shellfish and sediment of three French Mediterranean coastal lagoons using the most probable number-polymerase chain reaction (MPN-PCR). In summer, the total number of V. parahaemolyticus in water, sediment, mussels and clams collected from the three lagoons varied from 1 to >1.1 × 10³ MPN/l, 0.09 to 1.1 × 10³ MPN/ml, 9 to 210 MPN/g and 1.5 to 2.1 MPN/g, respectively. In winter, all samples except mussels contained V. parahaemolyticus, but at very low concentrations. Pathogenic (tdh- or trh2-positive) V. parahaemolyticus were present in water, sediment and shellfish samples collected from these lagoons. The number of V. vulnificus in water, sediment and shellfish samples ranged from 1 to 1.1 × 10³ MPN/l, 0.07 to 110 MPN/ml and 0.04 to 15 MPN/g, respectively, during summer. V. vulnificus was not detected during winter. V. cholerae was rarely detected in water and sediment during summer. In summary, results of this study highlight the finding that the three human pathogenic Vibrio spp. are present in the lagoons and constitute a potential public health hazard.     

Stage-dependent detection of CD14+ and CD16+ cells in the human heart after myocardial infarction

Monocytes are critically involved in cardiovascular wound healing processes. Human monocytes can be classified into two subsets based on the expression of CD14 and CD16. Here, we examined the temporal and spatial distribution of CD14⁺ and CD16⁺ cells after myocardial infarction (MI) in human heart and spleen tissue and correlated it with markers of cardiac repair. Heart samples obtained at autopsy were histologically classified into acute (AMI; n?=?11), subacute (SAMI; n?=?10) and old (OMI; n?=?16) MI, or control myocardium (CONTR; n?=?8). Histochemical analyses revealed marked fibrosis in OMI (p?<?0.001 vs. CONTR). The adhesion molecule CD56 was also strongly expressed in OMI (p?<?0.01 vs. CONTR) and found to correlate with fibrosis (p?<?0.001). The number of capillaries was reduced in OMI (p?<?0.01 vs. CONTR; p?<?0.05 vs. AMI), whereas the hypoxia indicator carbonic anhydrase IX was predominantly expressed in AMI (p?<?0.01 vs. OMI and CONTR) and SAMI (p?<?0.05 vs. OMI and CONTR). The monocyte chemoattractrant osteopontin was also more highly expressed in hearts of SAMI patients (p?<?0.01 vs. CONTR). Numbers of CD14⁺ monocytes were found to correlate with CD16⁺ cells (p?<?0.05) and inversely with fibrosis (p?<?0.05). Regarding a MI-associated release of monocytes from spleen reservoirs, a non-significant reduction of splenic CD14⁺ and CD16⁺ cells was detected in subjects with AMI. In conclusion, disease stage-specific alterations in CD14⁺ and CD16⁺ cells in human heart may contribute to cardiac repair processes following MI.     

Risk of acquiring tick-borne infections in forestry workers from Lazio, Italy

The seroprevalence of antibodies to Borrelia burgdorferi and tick-borne encephalitis (TBE) virus was evaluated in a group of forestry rangers in the Lazio region of Italy. One hundred and forty-five forestry rangers and 282 blood donors were examined by two-tiered serological tests for B. burgdorferi and TBE virus. Information on occupation, residence, tick bites, outdoor leisure activities and other risk factors was obtained. The prevalence of IgG/IgM antibodies to B. burgdorferi showed no statistical difference between the two groups, but there was a higher occurrence of IgM antibodies. There were significant differences between indoor and outdoor, urban and rural workplaces among the 145 exposed workers (χ² test: p?<?0.001), and a higher risk for outdoor rural than urban tasks was detected among the ten Western blot-tested forestry rangers positive to B. burgdorferi (χ² test: p?<?0.1). No seropositivity was observed for the TBE virus. Forestry rangers from the Lazio region did not have a higher risk of Borrelia infection than the blood donors, though an increase in the risk for outdoor tasks in a rural environment was observed.     

Volume changes in the forearm and lower limbs during 2 h of acute hypobaric hypoxia in nonacclimatized subjects

To investigate the role of fluid shifts during the short-term adjustment to acute hypobaric hypoxia (AHH), the changes in lower limb (LV) and forearm volumes (FV) were measured using a strain-gauge plethysmograph technique in ten healthy volunteers exposed to different altitudes (450 m, 2500 m, 3500 m, 4500 m) in a hypobaric chamber. Arterial blood pressure, heart rate, arterial oxygen saturation (S _aO₂), endtidal gases, minute ventilation and urine flow were also determined. A control experiment was performed with an analogous protocol under normobaric normoxic conditions. The results showed mean decreases both in LV and FV of ?0.52 (SD 0.39) ml?·?100 ml^?1 and ?0.65 (SD 0.32) ml?·?100 ml^?1, respectively, in the hypoxia experiments [controls: LV ?0.28 (SD 0.37), FV ?0.41 (SD 0.47) ml?·?100 ml^?1]. Descent to normoxia resulted in further small but not significant decreases in mean LV [?0.02 (SD 0.11) ml?·?100 ml^?1], whereas mean FV tended to increase slightly [?+?0.02 (SD 0.14) ml?·?100 ml^?1]; in the control experiments mean LV and FV decreased continuously during the corresponding times [?0.19 (SD 0.31), ?0.18 (SD 0.10) ml?·?100 ml^?1, respectively]. During the whole AHH, mean urine flow increased significantly from 0.84 (SD 0.41) ml?·?min^?1 to 3.29 (SD 1.43) ml?·?min^?1 in contrast to the control conditions. We concluded that peripheral fluid volume shifts form a part of the hypoxia-induced acute cardiovascular changes at high altitude. In contrast to the often reported formation of peripheral oedema after prolonged exposure to hypobaric hypoxia, the results provided no evidence for the development of peripheral oedema during acute induction to high altitude. However, the marked increase in interindividual variance in S _aO₂ and urine flow points to the appearance of the first differences in the short-term adjustment even after 2 h of acute hypobaric hypoxia.     

Contributory Anti-Inflammatory Effects of Mesenchymal Stem Cells,Not Conditioned Media,On Ovalbumin-Induced Asthmatic Changes in Male Rats

Our aim in selecting an appropriate cell fraction and conditioned media (CM) was to achieve the suitable candidate for ameliorating long-term chronic asthmatic changes of respiratory tract. Thirty-six rats were classified into healthy and sensitized groups, which were further divided into three subgroups; rats received systemically 50 μl volume of PBS, CM, or 2?×?10⁶ rat bone marrow-derived mesenchymal stem cells (rBMMSCs). Tracheal responsiveness (TR), immunologic responses, and recruitment of rBMMSCs into the lungs were evaluated. A high degree of TR and total WBC and percentages of eosinophils and neutrophils was significantly recorded in all sensitized groups rather than of controls (p?<?0.001 to p?<?0.05). Concurrently, a significant improvement of TR and eosinophil and neutrophil return toward normal levels was evident in sensitized rats receiving cells as compared to parallel asthmatic animals. Flow cytometric monitoring of lymphocyte subpopulation revealed a decrease in the number of CD3⁺CD4⁺ and concurrent increase in CD3⁺CD8⁺ in all sensitized rats as compared to control (p?<?0.001 to p?<?0.05). Noticeably, no significant modulatory effects of either cell or CM administration were achieved on the CD3⁺CD4⁺ and CD3⁺CD8⁺ populations in non-asthmatic rats. Corroborating our results, the number of CD3⁺CD4⁺ tended to increase (p?<?0.05) which coincided with a decreased manner of CD3⁺CD8⁺ populations as compared to other asthmatic groups (p?<?0.01 to p?<?0.05). Moreover, stem cells could efficiently transmigrate to the lung parenchyma, albeit the dynamic of asthmatic changes stimulated the rate of recruited cells. Our study shed light on superior effects of mesenchymal stem cells, but not CM, in attenuating chronic asthmatic changes in the model of rat.     

Achilles tendon loading during walking: application of a novel optic fiber technique

An optic fiber (Ø 0.5?mm) was utilized for the study of Achilles tendon forces (ATF) in eight volunteers who walked over a 10?m force platform at three speeds (1.1?±?0.1?m?×?s^?1, 1.5?±?0.1?m?×?s^?1 and 1.8?±?0.2?m?×?s^?1). The presented ATF-time curves showed great intersubject variation in magnitudes of the sudden release of force after initial contact and in the peak ATF's (1430?±?500?N). This intersubject variation in the peak force decreased only by 4% when cross-sectional area of the tendon was considered. Measured ground reaction forces and plantar pressures confirmed that the subjects walked quite normally during recordings. The peak ATF was found to be rather insensitive to speed in contrast to the rate of ATF development which increased 32% (?p?相似文献   

Volume and surface area estimates of astrocytes in the sensorimotor cortex of the cat

Electron micrographs of random sections through 133 astrocytes taken from the anterior and posterior sigmoid gyri of adult cats were used to estimate average astrocyte cell volume. Average soma volume was derived by two methods: (1) assuming that each approximated the shape of a prolate spheroid, a value of 2.2 ± 0.1 × 10^?13l. was calculated by substituting measurements of major (mean 10.4 ± 0.2 μm) and minor (mean 6.2 ± 0.1 μm) cell axes into the formula for volume; (2) applying Weibel's point-counting method of morphometry, a value of 1.9 ± 0.09 × 10^?13l. was obtained based on ratios of volume density and nuclear volume, calculated from measurements of nuclear axes. Because of the use of random sections through the cells sampled, the axial measurements on which both methods depend represent possible underestimations by as much as 21%; the resulting average value for soma volume might be as much as 3.2 × 10^?13l. Astrocyte somata from the deepest layer of the cortex had a significantly larger average volume than those from more superficial layers (P < 0.05). Average total cell volume (soma plus processes), estimated by calculating the volume of the tissue sample that was occupied by astrocytes and dividing that value by the number of astrocytes in the sample, amounted to 5.7 × 10^?13l. Point-counting morphometry revealed that 15.5% of the cortex consists of astrocytic cytoplasm. Average total cell surface area, estimated from intercepts of grid lines with cell membrane profiles of astrocytes within the sample, was 1.9 × 10^?5 cm²; average surface area of astrocyte somata, based on axial measurements, amounted to 2.5 × 10^?6 cm² or 13% of the surface area of the whole cell.Only 18 gap junctions were identified in the random sections through 133 astrocytes; these and other considerations bearing on the possible relationship of the data presented to electrical measurements in living astrocytes are discussed.     

Density of environmental Acanthamoeba and their responses to superheating disinfection

Exposure to viable Acanthamoeba may cause fatal encephalitis and blinding keratitis in humans. Quantification of environmental Acanthamoeba by a reliable analytical assay is essential to assess the risk of human exposure and efficacy of control measures (e.g., superheating). Two DNA binding dyes (ethidium monoazide (EMA) and propidium monoazide) coupled with real-time quantitative PCR (qPCR) were tested for the ability in selectively quantifying viable Acanthamoeba castellanii. This newly developed qPCR assay was applied to determine the density of environmental Acanthamoeba and disinfection efficacy of superheating. Results showed qPCR with 2.3 μg/mL EMA performed optimal with a great linearity (R ²?=?0.98) and a wide range of detection (5–1.5?×?10⁵ cells). EMA-qPCR analyses on water samples collected from cooling towers, eyewash stations, irrigated farmlands, and various wastewater treatment stages further showed viable Acanthamoeba density from nondetectable level to 6.3?×?10⁵ cells/L. Superheating A. castellanii at 75–95 °C for 20 min revealed significant reductions in both EMA-qPCR and qPCR detectable Acanthamoeba target sequences with an adverse association between heating temperature and qPCR-determined DNA quantity (r?=??0.76 to ?0.93, p?<?0.0001). Moreover, A. castellanii trophozoites were more sensitive to superheat stress than the cells being encysted for 6 and 13 d (p?<?0.05). This is the first study to quantify environmental Acanthamoeba and characterize their responses to superheating by EMA-qPCR. The quantitative data provided in this study facilitate to understand better the relative risk for human exposed to viable Acanthamoeba and the efficacy of superheating against Acanthamoeba.     

Effect of intense interval workouts on running economy using three recovery durations

The purposes of this study were to determine whether running economy (RE) is adversely affected following intense interval bouts of 10?×?400-m running, and whether there is an interaction effect between RE and recovery duration during the workouts. Twelve highly trained male endurance athletes [maximal oxygen consumption; V˙O_{2 max} =72.5 (4.3) ml·kg^?1·min^?1; mean (SD)] performed three interval running workouts of 10?×?400 m with a minimum of 4 days between runs. Recovery duration between the repetitions was randomly assigned at 60, 120 or 180 s. The velocity for each 400-m run was determined from a treadmill V˙O_{2 max} test. The average running velocity was 357.9 (9.0) m?·?min^?1. Following the workout, the rating of perceived exertion (RPE) increased significantly (P??1. Changes in RE from pre- to post-workout, as well as heart rate (HR) and respiratory exchange ratio (R) were similar for the three recovery conditions. When averaged across conditions, oxygen consumption (V˙O₂) increased significantly (P??1?·?min^?1 at 200?m?·?min^?1, and from 53.1 to 54.5?ml?·?kg^?1?·?min^?1 at 268 m?·?min^?1, respectively). HR increased (from 124 to 138, and from 151 to 157 beats?·?min^?1 respectively) and R decreased (from 0.90 to 0.78, and from 0.93 to 0.89, respectively) at 200 and 268 m?·?min^?1, respectively (P?V˙O₂, HR and R were independent of the recovery duration between the repetitions.     

Ceftobiprole medocaril is an effective treatment against methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis in a rat model

Methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis after median sternotomy is a major complication of cardiac surgery with significant morbidity and mortality rates. We evaluated the efficacy of ceftobiprole medocaril in a new rat model of mediastinitis and compared it to vancomycin. The model was induced in 92 rats. Infection was induced immediately after median sternotomy by the injection of MRSA (strain 3020, 1?×?10⁷ cfu/rat) into the sternal bone. After 24 h, rats (groups of 6–8) were treated intraperitoneally for 5 days or 14 days by either: (i) saline (control, q8h), (ii) ceftobiprole medocaril (70 or 100 mg/kg, q8h), or (iii) vancomycin (50 mg/kg, q12h). Efficacy was determined by a reduction in bacterial cfu in the sternum and spleen tissues. Comparisons were performed using the Mann–Whitney test. A 5-day treatment course of ceftobiprole at both doses tested lead to a significant reduction in MRSA load in the sternum (p?<?0.01) as compared to the control group and compared to 5-day vancomycin treatment, which lead to a non-significant reduction (p?=?0.07). Longer treatment (14 days) with ceftobiprole lead to a complete clearance of MRSA from the sternum, similarly to vancomycin. Ceftobiprole also showed a significant effect on eliminating MRSA dissemination to the spleen compared to saline-treated rats. Ceftobiprole was effective in treating MRSA mediastinitis in the rat model. In the 5-day course, ceftobiprole showed a significant reduction in sternal MRSA counts and was superior to vancomycin. After 14 days, both ceftobiprole and vancomycin showed clearance of MRSA from the sternum in more than 50 % of rats and almost complete clearance in the remainder.     

Effect of oxygen concentration on denitrification in freshwater sediment

The effect of different O₂ concentrations on denitrification in freshwater sediment was studied using the acetylene blockage technique. Denitrification occurred over a wide range of O₂ concentrations ranging from 10.1 to 0.33 μmol ml^?1 in nitrate amended sediment. However, denitrifying activity was not observed in sediment incubated under similar conditions when NO₃-was absent. These observations suggested that an anoxic environment or low O₂ concentrations were not required for denitrification to occur, if NO₃- was initially present in the sediment. Denitrification gradually decreased as the dissolved O₂ concentration in sediment increased to 0.25 μmol ml^?1. However, between 0.25 and 0.35 μmol ml^?1 dissolved O₂, denitrifying activity was higher than at the lower dissolved O₂ concentration (0.25 μmol ml^?1).     

The effect of self-licking behavior on pharmacokinetics of eprinomectin and clinical efficacy against Psoroptes cuniculi in topically administered rabbits

Ear mange mite Psoroptes cuniculi, one of the predominant parasites in rabbits, can cause considerable weight loss, low favorable fee conversion rates, and meningitis. The present experiment was to investigate the difference of plasma disposition and the variation of clinical efficacy under the effect of animal self-licking behavior in topically administered rabbits. Ten rabbits for pharmacokinetic study in two groups (the self-licking and the non-licking) were topically administered with 1 mg kg^?1 of eprinomectin. In the self-licking group, rabbits were allowed to self-lick freely, while, to prevent self-licking, each animal in the non-licking group was fitted with a pet collar. Compared to the non-licking group, self-licking behavior contributed to an extremely significant shorter half-life of absorption (14.85?±?2.79 h in licking group vs. 29.44?±?7.81 h in non-licking group, p?<?0.01) and an extremely significant higher C _max value for eprinomectin (21.95?±?5.36 h in licking group vs. 6.98?±?0.72 ng ml^?1 in non-licking group, p?<?0.01) in plasma disposition. An extremely significantly shorter mean residence time (50.72?±?3.45 h) in self-licking group was also determined compared with the value obtained in non-licking group (106.66?±?7.39 h; p?<?0.01). Clinical efficacy study of eprinomectin was examined in rabbits naturally infested with P. cuniculi which were randomly allocated in three groups: the self-licking, the non-licking, and control groups. All rabbits in the self-licking and the non-licking groups were treated with topical eprinomectin at a single dose of 2 mg kg^?1 (day 0). Topical eprinomection led to a complete parasitological recovery in both treated groups on day 14 and remained free of live mites and clinical lesions from day 21 to the end of the study period (day 35).     

Associations between interleukin-23R and interleukin-12B polymorphisms and psoriasis susceptibility: a meta-analysis

Objective: The aim of this study was to determine whether interleukin (IL)-23?R and IL-12B polymorphisms confer susceptibility to psoriasis.

Methods: The authors conducted a meta-analysis on associations between the IL-23?R and IL-12B polymorphisms and psoriasis susceptibility.

Results: A total of 14 comparison studies were included in this meta-analysis. The meta-analysis identified a significant association between psoriasis and 2 alleles of the rs11209026 and rs7530511 polymorphisms in Europeans (odds ratio [OR]?=?0.624, 95% confidence interval [CI]?=?0.565–0.697, p?<?1.0?×?10^?8; OR?=?0.804, 95% CI?=?0.743–0.869, p?=?3.0?×?10^?7, respectively). Meta-analysis of IL-12B showed a significant association between the 2 alleles of the rs6887695 and rs3212227 polymorphisms and the risk of developing psoriasis (OR?=?0.710, 95% CI?=?0.673–0.749, p?<?1.0?×?10^?8; OR?=?0.684, 95% CI?=?0.639–0.731, p?<?1.0?×?10^?8, respectively). Stratification by ethnicity identified an association between the rs6887695 and rs3212227 polymorphisms and psoriasis in Europeans.

Conclusions: This meta-analysis showed that the IL-23?R (rs11209026 and rs7530511) polymorphisms are associated with psoriasis risk in Europeans and that the IL-12B (rs6887695 and rs3212227) polymorphisms are associated with susceptibility to psoriasis in Europeans.     

A search for antiplasmodial metabolites among fungal endophytes of terrestrial and marine plants of southern India

Eighty four different fungal endophytes isolated from sea grasses (5), marine algae (36) and leaves or barks of forest trees (43) were grown in vitro and the secondary metabolites secreted by them were harvested by immobilizing them on XAD beads. These metabolites were eluted with methanol and screened using SYBR Green I assay for their antiplasmodial activity against blood stage Plasmodium falciparum in human red blood cell culture. Our results revealed that fungal endophytes belonging to diverse genera elaborate antiplasmodial metabolites. A Fusarium sp. (580, IC₅₀: 1.94 μg ml^?1) endophytic in a marine alga and a Nigrospora sp. (151, IC₅₀: 2.88 μg ml^?1) endophytic in a tree species were subjected to antiplasmodial activity-guided reversed phase high performance liquid chromatography separation. Purification led to potentiation as reflected in IC₅₀ values of 0.12 μg ml^-1 and 0.15 μg ml^?1 for two of the fractions obtained from 580. Our study adds further credence to the notion that fungal endophytes are a potential storehouse for a variety of novel secondary metabolites vested with different bioactivities including some that can stall the growth of the malaria parasite.