Comparative analysis of asymptomatic infection prevalence in Beta, Delta, and Omicron surges of COVID-19

Abstract Background The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has had a devastating impact on the global population, with an estimated 650 million people infected and more than 6.6 million lives lost. Asymptomatic individuals have been shown to play a significant role in the transmission of the virus. Therefore, this study aims to investigate and compare the prevalence of asymptomatic individuals across three waves associated with the Beta, Delta, and Omicron variants of the virus. Methods This retrospective study was conducted between December 2020 and March 2022. The study population consisted of passengers on international flights who were referred to the Gerash Clinical and Molecular Diagnosis Laboratory. Real-time PCR was employed for the diagnosis of SARS-CoV-2. Results Out of a total of 8592 foreign travelers referred to our laboratory, 139 (1.16 %) tested positive for SARS-CoV-2 infection and were asymptomatic. During the Beta surge, 35 (1.49 %) out of 2335 passengers tested positive for SARS-CoV-2. In the Delta surge, 31 (0.6 %) out of 5127 passengers tested positive. However, during the Omicron surge, a significantly higher number of passengers, specifically 73 (6.46 %) out of 1130, had a positive result for the SARS-CoV-2 test. Conclusion Considering the significant role of asymptomatic transmission in the spread of COVID-19, it is imperative to reconsider health policies when dealing with future surges of the Omicron subvariants. Additionally, we strongly recommend that the World Health Organization prioritize the development and distribution of second-generation vaccines that target not only disease but also infection prevention.

Investigating lead and zinc uptake and accumulation by Stipa hohenackeriana trin and rupr. in field and pot experiments / Investigação sobre a captação e acúmulo de chumbo e zinco por Stipa hohenackeriana trin. & rupr. em experimentos de campo e em vaso

This study was conducted to evaluate Pb and Zn uptake, mobility, and accumulation in Stipa hohenackeriana using field soil in pot and field experiments. Moreover, the effects of Municipal Solid Waste Compost (MSWC) (0, 1, and 2%) and Nano-Silica (NS) (0, 250, and 500 mg/kg) on Stipa biomass, Pb and Zn availability in the soil, and Pb and Zn uptake and accumulation were studied using pot experiments. Samples of soil, root, and shoots of Stipa were collected from field and greenhouse and after drying, extraction of Pb and Zn was done by acid digestion. Bio- Concentration Factor (BCF) and Translocation Factor (TF) were calculated to determine Pb and Zn phytoremediation efficiency. The amount of Zn and Pb remediation by Stipa from soil was determined by remediation factor (RF). The results of field experiments showed the Pb and Zn level decreased in the order of: soil >shoot>root. Results of the pot experiments also showed that plants grown in NS500-amended pots had 33% and 32% higher Pb in roots and shoots compared to control pots, respectively. In comparison, roots Pb concentration in pots amended with MSWC1% and MSWC2% decreased 22.4% and 1.7%, respectively. Roots and shoots Zn concentration in NS500-amended pots was 5.6% and 6.5% higher, respectively. However, root Zn concentration in treatments of MSWC1% and MSWC2% decreased 52.3% and 39.4%, respectively. Shoots Zn concentration decreased 52.5% and 40.0%, respectively. Although MSWC decreased the uptake and accumulation of Pb and Zn in Stipa roots and shoots, it improved the plant growth and consequently increased RF and soil remediation compared to the NS. Thus, it seems that applying MSWC and NS simultaneously can be a suitable strategy for the purpose of improving phytoremediation capability of Stipa in the Pb and Zn contaminated soils. In general, Stipa can be a suitable candidate for the accumulation of heavy metals, especially for Pb and Zn contaminated soils.

Este estudo foi conduzido para avaliar a absorção, mobilidade e acumulação de Pb e Zn em Stipa hohenackeriana em experiências usando solo de campo em vaso e em campo. Além disso, os efeitos do Composto Municipal de Resíduos Sólidos (MSWC) (0, 1 e 2%) e de nanopartículas de sílica (NS) (0, 250 e 500 mg/kg) na biomassa de Stipa, na disponibilidade de Pb e Zn no solo, e na absorção e acúmulo de Pb e Zn foram estudados usando experiências em vaso. Amostras de solo, raiz e brotos de Stipa foram coletadas do campo e da estufa e, após a secagem, a extração de Pb e Zn foi feita por digestão ácida. O Fator de Bioconcentração (BCF) e o Fator de Translocação (TF) foram calculados para determinar a eficiência de fitorremediação de Pb e Zn. A quantidade de remediação de Zn e Pb pela Stipa a partir do solo foi determinada pelo Fator de Remediação (RF). Os resultados das experiências de campo mostraram que o nível de Pb e Zn diminuiu na seguinte ordem: solo > broto > raiz. Os resultados das experiências em vaso também mostraram que as plantas cultivadas em vasos corrigidos com NS500 apresentaram teores de Pb 33% e 32% maiores em raízes e brotos em comparação com vasos de controle, respectivamente. Em comparação, a concentração de Pb em raízes em vasos corrigidos com MSWC1% e MSWC2% diminuiu 22,4% e 1,7%, respectivamente. A concentração de Zn em raízes e brotos em vasos corrigidos com NS500 foi de 5,6% e 6,5% maior, respectivamente. No entanto, a concentração de Zn da raiz nos tratamentos de MSWC1% e MSWC2% diminuiu 52,3% e 39,4%, respectivamente. A concentração de Zn nos brotos diminuiu 52,5% e 40,0%, respectivamente. Embora o MSWC tenha diminuído a absorção e acumulação de Pb e Zn nas raízes e brotos de Stipa, melhorou o crescimento da planta e consequentemente aumentou o RF e a remediação do solo em relação ao NS. Assim, parece que aplicar MSWC e NS simultaneamente pode ser uma estratégia adequada com o objetivo de melhorar a capacidade de fitorremediação de Stipa nos solos contaminados com Pb e Zn. Em geral, a Stipa pode ser um candidato adequado para a acumulação de metais pesados, especialmente para solos contaminados com Pb e Zn.

Association between the p53 codon 72 polymorphism and primary open‑angle glaucoma risk: Meta‑analysis based on 11 case–control studies.

The TP53 is important in functions of cell cycle control, apoptosis, and maintenance of DNA integrity. Studies on the association between p53 codon 72 polymorphism and primary open‑angle glaucoma (POAG) risk have yielded conflicting results. Published literature from PubMed and Web of Science databases was retrieved. All studies evaluating the association between p53 codon 72 polymorphisms and POAG were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated. Eleven separate studies including 2541 cases and 1844 controls were pooled in the meta‑analysis. We did not detect a significant association between POAG risk and p53 codon 72 polymorphism overall population except allele genetic model (C vs. G: OR = 0.961, 95% CI = 0.961–0.820, P = 0.622). In the stratified analysis for Asians and Caucasians, there was an association between p53 codon 72 polymorphism and POAG. In the dominant model in the overall population and by ethnicity subgroups, the highest elevated POAG risk was presented. In summary, these results indicate that p53 codon 72 polymorphism is likely an important genetic factor contributing to susceptibility of POAG. However, more case–controls studies based on larger sample size and stratified by ethnicity are suggested to further clarify the relationship between p53 codon 72 polymorphism and POAG.

Association of MMP 9-1562 C/T Single Nucleotide Polymorphism with the Susceptibility to Lung Cancer Disease in South Iranian Population.

Aims: The aim of this study was to investigate the association of MMP9 -1562 C /T single nucleotide polymorphism with lung cancer in south Iranian population. Matrix metalloproteinases (MMPs) are a family of highly conserved metal-dependent proteolytic enzymes that are able to degrade ECM components and regulate various cell behaviors. Among several candidate genes, MMP9 is one of the most important genes known to play a key role in relation to lung cancer initiation and progression. A common - 1562(C/T) single nucleotide polymorphism in the promoter region of MMP9 was reported to have an association with lung cancer disease. Study Design: A case - control study was carried out using 90 lung cancer patients and 100 healthy controls. Place and Duration of Study: Cellular and Molecular Gerash Research Center, Shiraz University of Medical sciences, shiraz, Iran, between 2010-2012. Methodology: The association of MMP9 promoter single nucleotide polymorphism and lung cancer was examined in a PCR-RFLP method. Our results suggest an association between MMP9 single nucleotide polymorphism and lung cancer initiation and progression. Conclusion: According to our results, the frequency of T allele in patient group (OR=4.6111, 95% CI, 1.9005 to 11.1879) and TT genotype in smoker group (OR=1.7726, 95% CI, 0.7947 to 3.9538) is higher compared to other groups.

Molecular detection of TT virus and SEN virus infections in hemodialysed patients and blood donors in south of Iran.

Background: SEN virus (SEN-V) and TT virus (TTV) have been classified in the circoviridae family. Both are single-stranded, non-enveloped DNA viruses of about 3800 nucleotides. Patients on maintenance hemodialysis (HD) have a high risk of blood-borne viral infections. SEN-V and TTV has been reported from a number of HD units from various countries throughout the world. Materials and Methods: A total of 377 blood samples obtained from 150 healthy donors and 227 HD patients were collected at the HD center. SEN-V and TTV DNA was determined by polymerase chain reaction (PCR) in all samples. Results: TTV was detected in 109 (48.01%) of 227 hemodialysed patients and 14 (9.33%) of 150 voluntary blood donors (significant, P < 0.05). The PCR results for SEN-V-D/H DNA showed that 65 (28.63%) were positive for SEN-V-D and 33 (14.53%) were positive for SEN-V-H. 9.69% of 227 patients were positive for SEN-V-D/H co-infection. In the control group, SEN-V-D was detected in 14 (9.33%) and SEN-V-H was detected in 15 (10%) of the 150 (100%) blood donors. Conclusion: These findings show that the prevalence of SEN-V-D/H and TTV is higher than healthy blood donors. Also, these results indicate that the prevalence of SEN-V and TTV infections in our region is similar with that in other countries.