Background: The importance of accurate diagnosis of all of major diseases cannot be underestimated and efficient laboratory testing is vital to identifying and treating life-threatening illnesses including malaria. In this study, we compared the potential of one of merozoite surface protein genes, PvMSP-3b, for detection of Plasmodium vivax in blood samples by PCR with routinely used marker, ssrRNA gene.Methods: One hundred P. vivax microscopy-positive blood samples were simultaneously tested with two genetic markers, including PvMSP-3b gene and ssrRNA gene by PCR and nestedPCR method, respectively, and their sensitivity and specificity in detection of P. vivax was compared.Results: An important difference was seen in sensitivity between the 2 genetic markers, 100% in case of ssrRNA gene vs. 95% of PvMSP-3b gene. The specificity of the two markers was same (100%). Microscopic diagnoses of thick and thin blood smears was used as "golden standard" method.Conclusion: Due to critical importance of accurate detection of the parasite in malarious area, the PvMSP-3b gene cannot be a suitable marker for detection of P. vivax in blood sample by PCR. More investigations are needed to find other valid markers.

Background and Aim: PCR has high sensitivity and specificity for the determination offungal DNA. It is also useful for rapid identification of the most common species of Aspergillus. The purpose of this study was to compare culture method with nested PCR method to determine Aspergillesion in diabetic foot patient in Imam Khomeini Hospital, Tehran.Material and Methods: Sixty-five cases of suspicious diabetic foot lesion Aspergillusis were examined under culture and molecular method. Aspergillus isolates were identified to genus level on the SGA. DNA extraction performed and PCR and Nested PCR reactions were done. Serum samples were collected and ELISA for anti bodies against all species were performed. Results were analyzed using ANOVA and P was considered significant at P<0.05.Results: Of the total of 65 samples, 39 were diagnosed as Aspergillos is obtained from cultures. In PCR and Nested PCR using specific primers, 41 samples were diagnosed as Aspergillus. PCR and Nested PCR for species recognition were equal but differences in gender were recognized. ELISA results showed that 39 samples were positive.Conclusion: Although PCR is less sensitive than nested PCR, but we can recognize the most common pathogenic species, Aspergillus fumigatus. Our results showed significant differences between the results of culture and NESTED-PCR in the identification of the Aspergillus genus.

2Background: Pneumocystis jirovecii (P. jirovecii) causes Pneumocystis pneumonia (PCP) in people, especially the immunocompromised ones. It is also one of the serious causes of numerous lung problems in affected patients. Since documented data about P. jirovecii is not available in patients with pulmonary infections in Tehran, this study aimed to investigate the molecular epidemiology and parasitology of Pneumocystis to determine the frequency of the organism infection. Methods: Bronchoalveolar lavage (BAL) samples were collected for 367 patients hospitalized in the lung department of Shariati Hospital in Tehran from July 2022 to July 2023. The samples were analyzed using Giemsa staining and molecular methods. After DNA extraction from samples, Nested polymerase chain reaction (Nested PCR) was employed for the amplification of the 18SrRNA gene and identification of P. jirovecii. The PCR products of Nested PCR were sequenced for final confirmation.  Results: Out of 367 samples, only one sample (0.27%) and 28 samples (6.7%) were found to be positive through parasitology and NestedPCR analysis, respectively. P. jirovecii was detected in seven (25%) and 21 (75%) immunocompromised and immunocompetent patients, respectively. Fever, shortness of breath and dry cough were the most common clinical symptoms among patients with Pneumocystosis. Patients with pulmonary disorders are prone to colonization by pneumocystis, which increases the risk of pneumocystosis and makes them a reservoir for transmission to susceptible people. Conclusion: It can be concluded that patients with distinct lung disease are prone to colonization by Pneumocystis and, importantly, are at risk of infection. Also, according to the current study, Nested PCR was a suitable method for detecting P. jirovecii organisms because it had a very high sensitivity and specificity.