In vitro evaluation of physicochemical variables on the nematophagous fungus Duddingtonia flagrans

Duddingtonia flagrans is a biological alternative to the use of anthelmintic drugs in ruminants. This fungus must be ingested by the animal, pass through the cavities of the digestive tract and reach the feces where it develops traps that capture the nematodes. The severe conditions encountered in this process negatively affect the fungus, which is reflected in the low recovery rates compared to the amount administered. The aim of this study was to evaluate independently the in vitro effect of typical physical and chemical conditions of the gastrointestinal cavities of ruminants on the concentration, viability, and the in vitro nematode predatory ability of the chlamydospores of D. flagrans. The factors evaluated individually were pH (2, 6, and 8), temperature (28 ± 2°C and 39 ± 2°C), exposure to artificial saliva, and milling. The results showed that the concentration and viability of D. flagrans were not affected by the action of pH, temperature, milling, or exposure to artificial saliva. Regarding the in vitro nematode predatory ability, a reduction was observed after the milling process and the exposure for 24 h at different pH.     

In vitro evaluation of the effect of the nematophagous fungi Duddingtonia flagrans, Monacrosporium sinense, and Pochonia chlamydosporia on Ascaris suum eggs

The in vitro effect of four isolates of the nematophagous fungi Duddingtonia flagrans (AC 001), Monacrosporium sinense (SF 53), and Pochonia chlamydosporia (VC 1 and VC 4) on eggs of Ascaris suum was evaluated. One hundred thousand A. suum eggs were plated on 2% water–agar with the grown isolates and control without fungus. After 7, 14, and 21 days, 100 eggs were removed and classified according to the following parameters: type 1, lytic effect without morphological damage to eggshell; type 2, lytic effect with morphological alteration of embryo and eggshell; and type 3, lytic effect with morphological alteration of embryo and eggshell, besides hyphal penetration and internal egg colonization. P. chlamydosporia showed ovicidal activity (p < 0.01), mainly of the type 3 effect, on A. suum eggs in the studied intervals of 13.3% (isolate VC 1) and 17.3% (isolate VC 4), 13.9% (VC 1) and 17.7% (VC 4), and 19% (VC 1) and 20% (VC4), respectively, at 7, 14, and 21 days. The other fungi showed no type 3 effect. P. chlamydosporia is a potential biological control agent of A. suum eggs.     

A study of the genetic variability of human respiratory syncytial virus in Croatia, 2006–2008

Human respiratory syncytial virus (HRSV) is a common etiological agent of acute lower respiratory tract disease in infants. The molecular epidemiology of HRSV in Croatia over four consecutive seasons (from 2006 to 2008) was investigated. A total of 72 HRSV samples were chosen from 696 screened cases in a pediatric clinic in Zagreb. Molecular characterization of HRSV revealed the predominance of HRSV group B viruses in the first two epidemic seasons and HRSV group A viruses in the next two seasons. According to the phylogenetic analysis, NA1 and BA9 were the predominant circulating HRSV genotypes detected during the study. Overall, 82.9% of all HRSV A strains belonged to the NA1 genotype. The HRSV B genotype BA9, detected in two consecutive seasons (2006 and 2007), was the predominant circulating HRSV B genotype, accounting for 80.6% of all HRSV B strains. This study provides data on the circulation pattern of HRSV genotypes in Croatia and their molecular characterization. J. Med. Virol. 84:1985–1992, 2012. © 2012 Wiley Periodicals, Inc.     

Comparative efficacy of the nematode-trapping fungus Duddingtonia flagrans against Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis in goat faeces: influence of the duration and of the temperature of coproculture

Amongst the alternative strategies to the use of anthelmintics, the administration of Duddingtonia flagrans spores has already proved its efficacy in reducing the number of developing larvae of several nematode species in goat faeces. In this trial, the efficacy of this fungus against the larvae of the three major nematode species of goats was compared in various conditions of coproculture. Twelve strongyle free goats were experimentally infected with either Trichostrongylus colubriformis, Teladorsagia circumcincta or Haemonchus contortus larvae. Half of the animals received an oral dose of 5×10⁵ Duddingtonia chlamydospores/kg BW daily for 27 days, whereas the remaining was kept as control goats. From the 7th day of administration onwards, individual coproscopical examinations as well as coprocultures, which were incubated 4, 7, 10 or 14 days at 21 or 28°C, were performed. The reduction in developing larvae due to the activity of Duddingtonia ranged from 62.8 to 99.5% compared to control. The trapping efficacy depended on temperature (better activity of the fungus at 21 than at 28°C) and on duration (larval reductions lower after 4 days than after 7, 10 and 14 days of coproculture). Teladorsagia larvae were the least trapped, and Haemonchus larvae were the most trapped.     

Functional characterization of SOR1, a gene required for resistance to photosensitizing toxins in the fungus Cercospora nicotianae

The Cercospora nicotianae SOR1 gene is required for resistance to singlet oxygen-generating photosensitizers. SOR1 was characterized in the wild-type and in five photosensitizer-sensitive mutant strains which are complemented to photosensitizer resistance by transformation with SOR1. Sequence analysis determined that three of the mutants contain SOR1 copies with mutations encoding substitutions in the protein-coding sequence; however, two other mutants had wild-type SOR1 protein and promoter sequences. All five mutants accumulate SOR1 mRNA at levels comparable to that of the wild-type strain. In the wild-type strain, SOR1 accumulation is enhanced two-fold by light, but is unaffected by the presence of cercosporin, the photosensitizer synthesized by C. nicotianae. Southern analysis indicates that SOR1 is present in other fungi that synthesize structurally related perylenequinone photosensitizers. Received: 30 May / 1 October 1998     

血压变异性和容积脉搏波特征参数变异性的关联分析

目的 分析血压变异性和容积脉搏波特征参数变异性的相关性,确定相关性较好的参数,为利用容积脉搏波特征参数的变异性来估计血压变异性提供理论依据.方法 同步连续采集运动前后19个样本的容积脉搏波信号和血压信号,根据容积脉搏波信号的波形特征,提取8个特征参数,利用皮尔森相关系数分析血压变异性和容积脉搏波特征参数变异性在时域的相...     

Analysis of the molecular and biological variability of Zucchini yellow mosaic virus isolates from Slovakia and Czech Republic

The diversity of ZYMV isolates was analysed by the biological and molecular characterisation of 11 isolates sampled from cucumber, squash and zucchini between 2001 and 2006 in various localities of Slovakia and Czech Republic. Analysis of the molecular variability targeting three separate genomic regions of the ZYMV genome [P1, P3 and (Cter)NIb-(Nter)CP] revealed a remarkable low level of nucleotide variability between isolates, despite their temporal and spatial distinction. Phylogenetic analysis based on the 5′-terminal part of the CP gene highlighted the close relatedness of Slovak, Czech and other central European isolates. Low level of genetic diversity within central European ZYMV isolates is in contrast to the diversity observed for isolates from other geographical regions, in particular Asia. No evidence of recombination in the ZYMV genome was detected. Sequence comparison between aggressive and moderate ZYMV isolates revealed one amino acid difference in the N-terminal part of the P3 protein, potentially involved in the tolerance breaking.     

Isolation and molecular identification of echovirus 13 isolated from patients of aseptic meningitis in Korea, 2002

During 2002, several epidemics of aseptic meningitis were attributed to echovirus 13 in Korea. The causative agents of these outbreaks were isolated and identified using rhabdosarcoma cells, HEp-2 and Buffalo green monkey kidney cells, and a neutralization test using monospecific antiserum. Fifty-four echovirus 13 isolates were isolated from patients with aseptic meningitis in the provinces, Seoul, Kyonggi, Gwangju, Jeonju, Busan, and Ulsan. Symptoms associated with aseptic meningitis infection in patients included the occurrence of headaches and mild fever. Molecular characterization of echovirus 13 samples was achieved by sequence and phylogenetic analyses on partial VP1 sequences from 20 Korean isolates and 10 foreign isolates listed in Genbank. Minor variation was observed among the Korean isolates, which formed a unique cluster with isolates of German and Japanese origin. The marked similarities between isolates could be attributed to a relatively recent arrival of the virus in Korea. This is the first such investigation of aseptic meningitis caused by echovirus 13 on the Korean peninsula.     

Thermotolerance of germlings and mycelium of the insect‐pathogenic fungus Metarhizium spp. and mycelial recovery after heat stress

The upper temperature limits for germination and growth were determined for Metarhizium acridum (ARSEF 324, 3341 and 3609), M. robertsii (ARSEF 2575), M. anisopliae (ARSEF 5749), and Aspergillus nidulans (ATCC 10074). Most of the Metarhizium species germinated well at 35 and 36 °C; however, compared to 28 °C, the growth was very slow (except ARSEF 5749 from Mexico, which germinated at 35 °C, but did not grow at 34 or 36 °C). Germination was severely impaired at 38 and 40 °C for all Metarhizium species. ARSEF 324 conidia were the most thermotolerant. Based on radial growth measurements, however, none of the M. anisopliae or M. robertsii isolates grew (produced visible colonies) during 10 days at 38 °C. All Metarhizium species kept at 38 and 40 °C for 10 days resumed growth when transferred to 28 °C, and they all sporulated. When the plates were held 10 days at 42 °C, however, only the two M. acridum isolates (ARSEF 324 and 3609) grew after returning to 28 °C, but with some delay. Conidia germinated at restrictive temperatures, but the growth was impaired or discontinued soon after germination. Nevertheless, when transferred to a permissive temperature, they produced colonies and new conidia. In contrast, the thermophilic A. nidulans germinated and grew well at 42 °C, and therefore was much more thermotolerant than any of the Metarhizium spp. isolates. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The evolution and molecular characteristics of H9N2 avian influenza viruses in Jiangxi of China

To understand the evolution and molecular characteristics of Jiangxi H9N2 viruses, we isolated 17 viruses in 2011 and analyzed their characteristics. Phylogenetic analyses revealed that their hemagglutinin genes originate from JS/1/00-like sublineage, neuraminidase genes originate from BJ/94-like sublineage, PB1, PA, NP, and NS genes all come from SH/F/98-like sublineage, PB2 genes originate from ST/163/04-like sublineage, while M genes come from G1-like sublineage. Genotype analysis showed that our isolates were classified as genotype 57. Molecular analyses indicated that our strains contained specific sites characteristic of low-pathogenic viruses. The current study once again highlights the necessity for continued surveillance of novel H9N2 viruses.     

Molecular analysis of measles virus genome derived from SSPE and acute measles patients in Papua,New Guinea

A very high annual incidence of 56 per million population below the age of 20 years for subacute sclerosing panencephalitis (SSPE) has been reported from Papua New Guinea (PNG). In a more recent study, we have confirmed this unusual high incidence for Eastern Highlands Province (EHP) of PNG. In the study, it was observed that the vaccination rate among SSPE patients registered at Goroka Base General Hospital (GBGH) in EHP was higher than that of other infants in the province in recent years. To identify the measles virus (MV) responsible for SSPE in EHP, sequence analysis of hypervariable region of the N gene was performed from 13 MV genomes: 2 amplified from clinical specimens of SSPE patients and 11 from acute measles patients. In 2 cases among the 11 with acute measles, nucleotide sequence of the entire H gene derived from isolated viruses was determined. Both nucleotide sequence and phylogenetic tree analyses showed that the amplified MV cDNAs were closely related to one another and belonged to the D3 genotype though they were different from any previously reported MV sequences. No genome sequences of vaccine strains were detected. These findings suggest that the MV strains prevailing in the highlands of PNG belong to genotype D3 of the MV and this wild-type MV rather than the vaccine strains was likely to be responsible for SSPE in these patients.     

Analysis of the biological and molecular variability of Watermelon mosaic virus isolates from Iran

Watermelon mosaic virus (WMV) is one of the most important viruses that causes different symptoms in Cucurbitaceae. WMV is a potyvirus with a worldwide distribution, but occurs most commonly in temperate and Mediterranean regions. Cucurbit species grown in Yazd, Esfahan, West Azerbaijan, Hormozgan, and Kerman provinces were surveyed for the relative incidence of WMV in 2004–2005. A total of 757 symptomatic cucurbit and 31 weed species were collected and assayed for infection with WMV. Of 788 leaf samples from cucurbit and weed plants, 190 samples were positive by double antibody sandwich ELISA (DAS-ELISA) using specific polyclonal antibody. Among the weed species tested only colocynth (Citrullus colocynthis) was found to be infected with WMV. The coat protein (CP) gene from 18 representative isolates was PCR amplified, cloned, sequenced, and compared with the sequences available in GeneBank. Phylogenetic analysis using 778 nucleotide long sequences of the coat protein gene showed that these isolates fell into two; groups I and II. Only one isolates (KER.JI.1) was classified in the group II. This isolate had a wider host range and infected Nicotiana debneyii and Datura metel. None of the other 17 isolates could infect these two species. Members of group I were divided into three subgroups; A, B, and C. The subgroup I_B appears to be a new subgroup comprising only of the Iranian isolates. Phylogenetic analysis based on 200 nucleotides coding for the N-terminal segment of the CP showed that all Iranian isolates except KER.JI.1 clustered with the previously reported WMV strains. All Iranian isolates had a DAG amino acid triplet which is involved in aphid transmissibility. This is the first report on sequence analysis of the nearly full-length CP cDNA clones of WMV isolates from Iran.     

Genetic variability and phylogeny of the high‐risk HPV‐31, ‐33, ‐35, ‐52, and ‐58 in central Brazil

More than 100 HPV types have been described, 13 of which are classified as high‐risk due to their association with the development of cervical cancer. The intratype genomic diversity of HPV‐16 and ‐18 has been studied extensively, while little data have been generated for other less common high‐risk types. The present study explores the nucleotide variability and phylogeny of the high‐risk HPV‐31, ‐33, ‐35, ‐52, and ‐58, in samples from Central Brazil. For this purpose, the LCR and the E6 and L1 genes were sequenced. Several variants of these HPV types were detected, some of which have been detected in other parts of the world. Furthermore, new variants of all types examined were characterized in a total of 13 new variants. Based on the E6 and L1 sequences, variants were described comprising conservative and non‐conservative amino acid changes. For phylogenetic tree construction, samples characterized in this study were compared to others described and submitted to GenBank previously. The phylogenetic analysis of HPV‐31, ‐33, ‐35, and ‐58 isolates did not reveal ethnic or geographical clustering as observed previously for HPV‐16 and ‐18. HPV‐35 analysis showed a dichotomic branching characteristic of viral subtypes. Interestingly, four clusters relative to the analysis of HPV‐52 isolates were identified, two of which could be classified as Asian and European branches. The genomic characterization of HPV variants is crucial for understanding the intrinsic geographical relatedness and biological differences of these viruses and contributes further to studies on their infectivity and pathogenicity. J. Med. Virol. 81:685–692, 2009 © 2009 Wiley‐Liss, Inc.     

Morphological,cytogenetic and molecular biological characteristics of lung cancer in persons exposed for a long time to radionuclide radiation pollution in the Semipalatinsk region of Kazakhstan

Surgical and biopsy material was used from 57 patients with lung carcinoma (LC): 17 patients (group I) lived close to testing area from the childhood to 1993 and were exposed to radiation at the year dose 0.1 ber. For comparison surgical and biopsy material from 40 patients (group 2) was taken who lived in the territories of Kazakhstan (10 patients) and Moscow (30 patients) with normal radiation background. The following features of LC were found in the groups in question: constant observation of dust particles and interstitial and focal fibrosis in tumours of various localization and histological type; prevailing small cell carcinoma as compared to other histological types; high frequency of nonsmall cell lung carcinoma; higher expression of IGFII, IGFBP1,2 and rare expression of IGFB3; proliferative activity followed by an increased expression of c-myc, bcl-2.     

Analysis of pulse rate variability derived from photoplethysmography with the combination of lagged Poincaré plots and spectral characteristics

A combination of lagged Poincaré plots and spectral characteristics were used to investigate the effect of cigarette smoking on the autonomic nervous system (ANS). Heart rate variability (HRV) was determined from pulse-to-pulse intervals (PPI) of ear photoplethysmography (PPG) waveforms. Spectral power analysis of the pulse rate variability (PRV) was performed to determine low frequency (LF) and high frequency (HF) components, and a lagged Poincaré plot was introduced to evaluate the nonlinear characteristics of PRV. The correlations between lagged Poincaré plot and spectral power indices were studied in a group of apparently healthy habitual cigarette smokers and compared to non-smokers. The width (SD1_m) and the length (SD2_m) of lagged Poincaré plots significantly shrunk in the smokers for all lags (p < 0.05) except SD1₄ and SD1₅. The results of this pilot study indicated that habitual smoking is associated with parasympathetic withdrawal and augments sympathetic nerve activity. The results also demonstrated that the combination of lagged Poincaré plots and spectral characteristics could show promise as a method for distinguishing between different cardiovascular disease groups.