scholarly journals Molecular prevalence of Trypanosoma spp. in wild rodents of Southeast Asia: influence of human settlement habitat

2013 ◽  
Vol 142 (6) ◽  
pp. 1221-1230 ◽  
Author(s):  
P. PUMHOM ◽  
D. POGNON ◽  
S. YANGTARA ◽  
N. THAPRATHORN ◽  
C. MILOCCO ◽  
...  

SUMMARYThis study investigated the molecular prevalence of Trypanosoma lewisi and T. evansi in wild rodents from Cambodia, Lao PDR and Thailand. Between 2008 and 2012, rodents (and shrews) were trapped in nine locations and 616 of these were tested using three sets of primers: TRYP1 (amplifying ITS1 of ribosomal DNA of all trypanosomes), TBR (amplifying satellite genomic DNA of Trypanozoon parasites) and LEW1 (amplifying ITS1 of ribosomal DNA of T. lewisi). Based on the size of the PCR products using TRYP1, 17% were positive for T. lewisi and 1·0% positive for Trypanozoon. Results were confirmed by sequencing PCR products and by using more specific primers (LEW1 and TBR). The specificity of TRYP1 primers, however, failed as rodent DNA was amplified in some instances, giving unexpected product sizes. Using LEW1 primers, 13·3% of the samples were confirmed positive for T. lewisi, both by PCR and sequencing. In Thailand, T. lewisi was found in Rattus tanezumi, R. exulans and Berylmys; in Lao PDR, in R. tanezumi and R. exulans, and in Cambodia in R. tanezumi, R. exulans and R. norvegicus. Using TBR, 1·3% of the samples tested positive for Trypanozoon by PCR and sequencing; T. evansi is the only species of the Trypanozoon subgenus possibly present in wild Asian rodents. These results confirmed its presence in rodents from Thailand (R. tanezumi), Lao PDR (R. tanezumi, R. nitidus) and Cambodia (R. tanezumi, Niviventer fulvescens, Maxomys surifer). Based on the information related to rodent trapping, it was found that rodent species trapped in and around human dwellings had a higher prevalence of T. lewisi infection. R. tanezumi and R. exulans, two synanthropic species, were mainly found infected in this habitat suggesting a role as a reservoir and thus a potential source of T. lewisi for human infection.

2012 ◽  
Vol 12 (5) ◽  
pp. 1155
Author(s):  
Marc Desquesnes ◽  
Ketsarin Kamyingkird ◽  
Sarawut Yangtara ◽  
Cristina Milocco ◽  
Sophie Ravel ◽  
...  

2011 ◽  
Vol 11 (6) ◽  
pp. 1361-1367 ◽  
Author(s):  
Desquesnes Marc ◽  
Kamyingkird Ketsarin ◽  
Yangtara Sarawut ◽  
Milocco Cristina ◽  
Ravel Sophie ◽  
...  

Nematology ◽  
2009 ◽  
Vol 11 (6) ◽  
pp. 847-857 ◽  
Author(s):  
Lieven Waeyenberge ◽  
Nicole Viaene ◽  
Maurice Moens

Abstract ITS1, the 5.8S rRNA gene and ITS2 of the rDNA region were sequenced from 20 different Pratylenchus species. Additionally, the same region was sequenced from seven populations of P. penetrans. After purifying, cloning and sequencing the PCR products, all sequences were aligned in order to find unique sites suitable for the design of species-specific primers for P. penetrans. Since ITS regions showed variability between and even within populations of P. penetrans, only three small DNA sequences were suitable for the construction of three potentially useful species-specific primers. New species-specific primers were paired with existing universal ITS primers and tested in all possible primer combinations. The best performing primer set, supplemented with a universal 28S rDNA primer set that served as an internal control, was tested in duplex PCR. The ideal annealing temperature, Mg2+ concentration and primer ratios were then determined for the most promising primer set. The optimised duplex PCR was subsequently tested on a wide range of different Pratylenchus spp. and 25 P. penetrans populations originating from all over the world. To test the sensitivity, the duplex PCR was conducted on DNA extracted from a single P. penetrans nematode mixed with varying amounts of nematodes belonging to another Pratylenchus species. Results showed that a reliable and sensitive P. penetrans species-specific duplex PCR was constructed.


2017 ◽  
Vol 108 (2) ◽  
pp. 271-281 ◽  
Author(s):  
S. Karimi ◽  
H. Izadi ◽  
M. Askari Seyahooei ◽  
A. Bagheri ◽  
P. Khodaygan

AbstractThe date palm hopper,Ommatissus lybicus, is a key pest of the date palm, which is expected to be comprised of many allopatric populations. The current study was carried out to determine bacterial endosymbiont diversity in the different populations of this pest. Ten date palm hopper populations were collected from the main date palm growing regions in Iran and an additional four samples from Pakistan, Oman, Egypt and Tunisia for detection of primary and secondary endosymbionts using polymerase chain reaction (PCR) assay with their specific primers. The PCR products were directly sequenced and edited using SeqMan software. The consensus sequences were subjected to a BLAST similarity search. The results revealed the presence of ‘CandidatusSulcia muelleri’ (primary endosymbiont) andWolbachia,ArsenophonusandEnterobacter(secondary endosymbionts) in all populations. This assay failed to detect ‘CandidatusNasuia deltocephalinicola’ andSerratiain these populations. ‘Ca. S. muelleri’ exhibited a 100% infection frequency in populations andWolbachia,ArsenophonusandEnterobacterdemonstrated 100, 93.04 and 97.39% infection frequencies, respectively. The infection rate ofArsenophonusandEnterobacterranged from 75 to 100% and 62.5 to 100%, respectively, in different populations of the insect. The results demonstrated multiple infections by ‘Ca. Sulcia muelleri’,Wolbachia,ArsenophonusandEnterobacterin the populations and may suggest significant roles for these endosymbionts on date palm hopper population fitness. This study provides an insight to endosymbiont variation in the date palm hopper populations; however, further investigation is needed to examine how these endosymbionts may affect host fitness.


2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Xiaoxiao Zhu ◽  
Hoi-Yan Wu ◽  
Pang-Chui Shaw ◽  
Wei Peng ◽  
Weiwei Su

Abstract Background Pheretima is a minister drug in Naoxintong capsule (NXTC), a well-known traditional Chinese medicine (TCM) formula for the treatment of cardiovascular and cerebrovascular diseases. Owing to the loss of morphological and microscopic characteristics and the lack of recognized chemical marker, it is difficult to identify Pheretima in NXTC. This study aims to evaluate the feasibility of using DNA techniques to authenticate Pheretima, especially when it is processed into NXTC. Methods DNA was extracted from crude drugs of the genuine and adulterant species, as well as nine batches of NXTCs. Based on mitochondrial cytochrome c oxidase subunit I (COI) gene, specific primers were designed for two genera of genuine species, Metaphire and Amynthas, respectively. PCR amplification was performed with the designed primers on crude drugs of Pheretima and NXTCs. The purified PCR products were sequenced and the obtained sequences were identified to species level with top hit of similarity with BLAST against GenBank nucleotide database. Results Primers MF2R2 and AF3R1 could amplify specific DNA fragments with sizes around 230–250 bp, both in crude drugs and NXTC. With sequencing and the BLAST search, identities of the tested samples were found. Conclusion This study indicated that the molecular approach is effective for identifying Pheretima in NXTC. Therefore, DNA identification may contribute to the quality control and assurance of NXTC.


Plant Disease ◽  
2012 ◽  
Vol 96 (5) ◽  
pp. 769-769 ◽  
Author(s):  
J. Víchová ◽  
B. Staňková ◽  
R. Pokorný

Apple (Malus domestica Borkh.) is a fruit traditionally grown in the Czech Republic, and tomatoes (Solanum lycopersicum Mill.), too, are widely raised in this region. Colletotrichum acutatum J. H. Simmonds is a polyphagous fungal plant pathogen. Earlier, this pathogen caused disease on strawberry in the Czech Republic (2), and now it has become an important pathogen on safflower (4). During the 2010 harvest, anthracnose symptoms were noticed on the fruits of apple and tomato. Infected apples fruits (localities Velká Bíteš and Znojmo) and tomatoes (localities Velká Bíteš and Žabčice) were collected. Typical symptoms on fruit surfaces were round, brown, shriveled and sunken spots, 1.2 to 2.0 cm, with orange conidial masses appearing on the spots. A fungus was isolated from each host on potato dextrose agar and cultured at 25 ± 2°C for 10 days. Mycelium was superficial, partly immersed, and white to gray with occurrence of orange conidial masses. Conidia of the tomato and apple isolates were colorless and fusiform. The size of conidia from the apple and tomato isolates, respectively, ranged from 11 to 15 × 2.5 to 3.5 μm and 11 to 16 × 2.5 to 4 μm. Morphological characteristics suggested that the isolated fungi was a Colletotrichum sp. To fulfill Koch's postulates, healthy tomato and apple fruits were disinfected with 3% sodium hypochlorite for 2 min and rinsed in sterile distilled water. Fruits were pinpricked with a sterile needle and 10 μl of a spore suspension (1 × 105 conidia ml–1) was inoculated by pipetting into the wound. Control fruits were treated with sterile distilled water. The fruits were transferred to a growth cabinet and maintained at a temperature of 25 ± 2°C, relative humidity of 70 ± 5%, and a photoperiod of 12 h. Similar disease symptoms as in the collected fruits were observed on tomato fruits at 7 days and apple fruits at 20 days after inoculation, while no symptoms appeared on control fruits. The pathogen was reisolated from infected fruits. Species determination of the isolates was confirmed by PCR. Specific primers designed in region ITS1, the 5.8S RNA gene, and region ITS2 of the pathogen DNA were selected. Specific primers CaInt2 and ITS4 were used to identify C. acutatum (3), and primers CgInt and ITS4 were used to determine C. gloeosporioides isolate CCM 177 (1), which was used as a control. Our isolates yielded PCR products (490 bp) only with primers designed for C. acutatum. The C. gloeosporioides isolate yielded a PCR product (450 bp) only with CgInt and ITS4 primers. PCR products were sequenced and identified with the BLAST program. The sequence of the tomato fruit isolate (Accession No. JN676199) and apple fruit isolate (Accession No. JN676198) matched with 100% similarity to the C. acutatum sequences in GenBank. The control isolate of C. gloeosporioides matched 100% to sequences AJ749682 and AJ749692. To our knowledge, this is the first report of C. acutatum on tomato and apple fruits in the Czech Republic. This pathogen can endanger the production and storage of apples and tomatoes in this region. References: (1) P. R. Mills et al. FEMS Microbiol. Lett. 98:137, 1992. (2) D. Novotný et al. Plant Dis. 91:1516, 2007. (3) S. Sreenivasaprasad et al. Plant Pathol. 45:650, 1996. (4) J. Víchová et al. Plant Dis. 95:79, 2011.


2009 ◽  
Vol 72 (1) ◽  
pp. 182-184 ◽  
Author(s):  
JORGE F. CERNA-CORTÉS ◽  
TERESA ESTRADA-GARCÍA ◽  
JORGE A. GONZÁLEZ-y-MERCHAND

Recently human illnesses due to nontuberculous mycobacteria (NTM) have increased worldwide, but the sources of transmission have not been well established. Street-vended food is widely consumed in Mexico, and chili sauces are the most typical dressings for this food. Thus, we examined street-vended chili sauces as a possible source for NTM. Fifty-one street-vended chili sauces were collected in different areas of Mexico City during the spring of 2007. NTM were recovered from 6% (3 of 51) of samples, and in all cases the identified species was Mycobacterium mucogenicum. This mycobacterium has been associated with human illness; therefore, street-vended chili sauces are a potential source of NTM infection.


Plant Disease ◽  
2006 ◽  
Vol 90 (8) ◽  
pp. 1098-1101 ◽  
Author(s):  
Ainong Shi ◽  
Margaret T. Mmbaga

The fungus Erysiphe lagerstroemiae is commonly known as the powdery mildew pathogen in crape myrtle (Lagerstroemiae indica) in the United States, and Erysiphe australiana is the powdery mildew pathogen reported in Japan, China, and Australia. The teleomorph often used to identify powdery mildew fungi rarely develops in crape myrtle, and in our observations, ascocarps never formed. Our study showed that the crape myrtle pathogen overwintered as mycelia on dormant buds. The internal transcribed spacer (ITS) regions of rDNA and the intervening 5.8S rRNA gene were amplified using standard polymerase chain reaction (PCR) protocols and the universal primer pairs ITS1 and ITS4. PCR products were analyzed by electrophoresis in a 1.5% agarose gel and sequenced, and the ITS PCR product was 666 bp from ITS1/ITS4 and 704 bp from ITS1-F/ITS4. BLAST analysis of the sequence of the PCR products showed identical similarity with E. australiana reported in Japan, China, and Australia. Comparison of ITS sequences with information in the GenBank on other powdery mildew fungi showed a closest alignment (93% similarity) to Erysiphe juglandis that infects walnut. Specific primers for E. australiana were developed and evaluated for use as diagnostic tools. Out of 12 specific primer pairs evaluated, four primer pairs and four double primer pairs were highly specific to E. australiana and did not amplify Erysiphe pulchra of dogwood, Erysiphe syringae of common lilac, Erysiphe circinata of maple, or Phyllactinia guttata of oak. The E. australiana-specific primers amplified 16 samples of crape myrtle powdery mildew collected from diverse locations in mid-Tennessee. These results clearly showed that the crape myrtle powdery mildew in mid-Tennessee was caused by E. australiana. Specific primers reported in this article provide a diagnostic tool and may be used to confirm the identity of crape myrtle powdery mildew pathogen in other areas in the United States and wherever the disease occurs.


2012 ◽  
Vol 6 (6) ◽  
pp. 442-448 ◽  
Author(s):  
Srey V. Horm ◽  
Ramona A. Gutiérrez ◽  
San Sorn ◽  
Philippe Buchy

Plant Disease ◽  
1997 ◽  
Vol 81 (10) ◽  
pp. 1143-1149 ◽  
Author(s):  
A. W. Zhang ◽  
G. L. Hartman ◽  
L. Riccioni ◽  
W. D. Chen ◽  
R. Z. Ma ◽  
...  

Restriction fragment length polymorphism analyses of polymerase chain reaction (PCR) amplified DNA were used to distinguish Diaporthe phaseolorum and Phomopsis longicolla isolates from other soybean fungal pathogens. Primers made to the conserved sequences of nuclear ribosomal DNA amplified the internal transcribed spacer (ITS) regions of D. phaseolorum var. meridionalis and P. longicolla. The PCR products were cloned and then sequenced. Specific-primers, Phom.I and Phom.II, were designed from the polymorphic regions of D. phaseolorum and P. longicolla isolates from soybean to distinguish them from other soybean fungal pathogens. These ITS-derived primers amplified a 337-bp-specific DNA fragment from P. longicolla, D. phaseolorum var. meridionalis, D. phaseolorum var. caulivora, D. phaseolorum var. sojae, and Phomopsis spp. from 20 different hosts. No amplified product was observed using DNA of seven other soybean fungal pathogens or soybean DNA. The detection limit of PCR using primers Phom.I and Phom.II was 2.5 × 10-7 dilution of fungal DNA extracted from samples of 10 pooled seeds and as low as a 1:15 (Phomopsis:soybean) ratio when using 10 ng of DNA per μl from each P. longicolla and soybean. PCR did not produce products using primers Phom.I and Phom.II with DNA extracted from noninfected seeds, but specific bands were observed from samples of 10 pooled seeds and from individually infected seeds. A specific band was observed as well from DNA extracts of tissue samples from symptomless plants inoculated with P. longicolla and D. phaseolorum var. sojae.


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