Culex (Diptera: Culicidae) Mosquitoes in Jazan Region, Saudi Arabia, and Their Molecular Identification

Morphological characteristics have been the gold standard method to identify mosquito species. However, morphological identification has many limitations including lack of expertise and damaging of external characters due to improper specimen handling. Therefore, we used the polymerase chain reaction technique (PCR) as an integrated tool to identify Culex mosquito species to establish a more precise and reliable identification system related to their spatial distribution in Jazan region. We identified Culex mosquito species and subspecies using taxonomic keys, and then we used the polymerase chain reaction technique (PCR) as an integrated tool to confirm and refine the list of Culex mosquito species in the region. Phylogenetic trees were constructed for the identified species, and their distinctive clustering was compared with their reference’s species in the GenBank. We identified 7026 adult Culex mosquitoes belonging to 4 species. Culex tritaeniorhynchus was the predominant species (45%), followed by Cx. quinquefasciatus (32%), then Culex sitiens (20%), and Cx. pipiens (3%). The most infested areas by Culex in the region were Gizan and Sabya. The PCR achieved 100% success in identifying the four Culex mosquito species. We also report the molecular identification of Cx. quinquefasciatus and Cx. pipiens species for the first time in Jazan region while the molecular identification of Cx. tritaeniorhynchus and Cx. sitiens was reported for the first time in Jazan region and the whole Saudi Arabia. This study utilized for the first time PCR to identify Culex mosquito species in Jazan region. The PCR is a complementary and integrated taxonomy-based identification tool for mosquito species. This integration has the capacity to promote and enhance vector surveillance and control programs, as well as defining the genetic diversity of species in the region.

Detección de papilomavirus mediante reacción en cadena de la polimerasa en mujeres atendidas en el norte de Perú

Objective: The present study was conducted with the objective of determining the incidence of patients with human papillomavirus infection with unknown cytology using the polymerase chain reaction technique in a hospital in northern Peru. Methods: DNA was extracted from cervical citobrush samples using the Salting Out method. The DNA that was extracted and amplified by polymerase chain reaction technique using primers MY09 and MY11. Results: The samples were analyzed in 243 patients; the average age was 44 years. using the polymerase chain reaction technique, 13 patients (5.35 %) were found with a positive result for the presence of human papillomavirus, this as a part of a screening program in a Level III hospital in northern Peru. Conclusions: The incidence of human papillomavirus was low. There was no association between educational level, marital status, age, first sexual intercourse and human papillomavirus infection. No association was found between the number of sexual partners and human papillomavirus infection. Keywords: Human papilloma virus, Polymerase chain reaction, DNA probes, Papillomavirus Infections.

Diversity of Staphylococcus coagulase- positive and negative strains of coalho cheese and detection of enterotoxin encoding genes

Three hundred samples of coalho cheese, from 15 different brands, of which seven were handmade made and eight industrialized, were evaluated in relation to the contamination profile by Staphylococcus coagulase-positive and negative and the occurrence of staphylococcal enterotoxin encoding genes. Two hundred and eight isolates of Staphylococcus sp. were subjected to phenotypic identification and 95 were subjected to genotypic identification through femA gene research and detection of genes (sea, seb, sec, sed, see, seg, seh, sei and sej) encoding enterotoxins, using the polymerase chain reaction technique (PCR). A total of 14 species of Staphylococcus were identified, of which three were coagulase-positive and eleven negative, especially: S. aureus, S. xylosus, S. cohnni spp. cohnii, S. saprophyticus, S. epidermidis, S. hyicus, S. lentus, S. sciuri, S. cohnii spp. urealyticus, S. haemolyticus, S. chromogenes, S. lugdunensis, S. hominis e S. intermedius. In all the samples of handmade coalho cheese handmade there was a prevalence of S. aureus; while in the industrial samples S. xylosus (87.5%) and S. cohnii spp cohnii (50%) were predominant. The presence of the femA gene was detected in 95% (38/40) isolates of positive Staphylococcus coagulase and 16.4% (9/55) of coagulase-negative isolates. Among the enterotoxin encoding genes evaluated, there was prevalence of the seh gene (53.2%) in coagulase-positive strains and of the sec gene (46.8%) in coagulase-negative strains. The results suggest a re-evaluation of the Brazilian microbiological standards in relation to the genus Staphylococcus in foods.