Sayed Mostafa Hosseini, Mojtaba Saadati, Mohammad Bagher Yakhchali, Bahar Nayeri Fasaei , Hoora Ahmadydanesh, Morteza Mirzaei, Kamal Baghery, Mokhtar Zare,
Volume 15, Issue 2 (6-2012)
Abstract
Background: Live attenuated Shigella vaccines have shown promise in inducing protective immune responses in human clinical trials. The aim of this study was to design and construct pDS132::∆icsA as a suicide plasmid for targeted deletion of a region of icsA gene in Shigella. Materials and Methods: In this experimental study, species and serotypes of Shigella isolated from diarrhea samples of children at Firozabadi and Milad Hospitals of Tehran were confirmed by using serological and PCR tests. Identification primers of icsA gene were designed and then cloned to the pGEM-5zf vector and sequenced. According to icsA restriction enzyme map, 1751 bp of icsA gene was deleted by HincП restriction enzyme and the ∆icsA was constructed successfully. The pGEM∆icsA vector was digested by use of SphI and SalI enzymes and was then cloned to a suicide vector (pSD132). Precision of the process was confirmed by phenotype and genotype tests. Results: The Shigella dysenteriae type 1 strain was verified by serological tests and PCR. Sequence of the icsA gene in the native strain was identical to the strains submitted in the gene-bank database. Since the pDS132::∆icsA contains 1484 bp derived from icsA gene, it can be used to disrupt icsA gene as a specific suicide vector. Conclusion: Application of suicide systems facilitated mutant construction in more specific and effective methods in comparison with the other primary techniques such as serial passage.
Fatemeh Sadat Asgarian, Sahar Bayat, Mohammadhossein Khorasanizadeh,
Volume 28, Issue 6 (1-2026)
Abstract
Introduction: Suicidal ideation is influenced by social, economic, cultural, biological, psychological, and environmental factors. This study aimed to estimate the prevalence of suicidal ideation in the general population during the COVID-19 pandemic based on global studies.
Methods: All cross-sectional and cohort studies conducted on the prevalence of suicidal ideations in the general population during the COVID-19 pandemic were included in a systematic search of the following databases: Medlib, SID, Iranmedx, PubMed, Magiran, Science Direct, Scopus, and Web of Science, in English and Persian from 2019 to March 2023, without any restrictions. A random effects model was used for data analysis at a 95% confidence level to obtain a summary measure. Heterogeneity among results was assessed using the I² statistical test.
Results: In this review, 39 articles met the study inclusion criteria. According to the studies, the prevalence of suicidal ideations in the general population during the COVID-19 pandemic was 10% (CI: 0.09–0.12, 95%), and the prevalence of suicidal ideations was equal among women and men.
Conclusions: Assessing suicidal ideation is a primary indicator for predicting future suicidal behavior and provides vital insight into an individual's psychological distress and specific needs. However, when these thoughts are accompanied by clear intent and a concrete plan, the situation constitutes a psychiatric emergency and necessitates immediate and serious intervention.
