Ketamine-based sedation use in mechanically ventilated critically ill patients with COVID-19: A multicenter cohort study

Backgrounds: Ketamine possesses analgesia, anti-inflammation, anticonvulsant, and neuroprotection properties. However, the evidence that supports its use in mechanically ventilated critically ill patients with COVID-19 is insufficient. The study's goal was to assess ketamine's effectiveness and safety in critically ill, mechanically ventilated (MV) patients with COVID-19. Methods: Adult critically ill patients with COVID-19 were included in a multicenter retrospective-prospective cohort study. Patients admitted between March 1, 2020, and July 31, 2021, to five ICUs in Saudi Arabia were included. Eligible patients who required MV within 24 hours of ICU admission were divided into two sub-cohort groups based on their use of ketamine (Control vs. Ketamine). The primary outcome was the length of stay (LOS) in the hospital. P/F ratio differences, lactic acid normalization, MV duration, and mortality were considered secondary outcomes. Propensity score (PS) matching was used (1:2 ratio) based on the selected criteria. Results: In total, 1,130 patients met the eligibility criteria. Among these, 1036 patients (91.7 %) were in the control group, whereas 94 patients (8.3 %) received ketamine. The total number of patients after PS matching, was 264 patients, including 88 patients (33.3 %) who received ketamine. The ketamine group's LOS was significantly lower (beta coefficient (95 % CI): −0.26 (−0.45, −0.07), P = 0.008). Furthermore, the PaO2/FiO2 ratio significantly improved 24 hours after the start of ketamine treatment compared to the pre-treatment period (6 hours) (124.9 (92.1, 184.5) vs. 106 (73.1, 129.3; P = 0.002). Additionally, the ketamine group had a substantially shorter mean time for lactic acid normalization (beta coefficient (95 % CI): −1.55 (−2.42, −0.69), P 0.01). However, there were no significant differences in the duration of MV or mortality. Conclusions: Ketamine-based sedation was associated with lower hospital LOS and faster lactic acid normalization but no mortality benefits in critically ill patients with COVID-19. Thus, larger prospective studies are recommended to assess the safety and effectiveness of ketamine as a sedative in critically ill adult patients

Prevalence and Genetic Diversity of Cross-Assembly Phages in Wastewater Treatment Plants in Riyadh, Saudi Arabia

The most common DNA virus found in wastewaters globally is the cross-assembly phage (crAssphage). King Saud University wastewater treatment plant (KSU-WWTP); Manfoha wastewater treatment plant (MN-WWTP); and the Embassy wastewater treatment plant (EMB-WWTP) in Riyadh, Saudi Arabia were selected, and 36 untreated sewage water samples during the year 2022 were used in the current study. The meteorological impact on crAssphage prevalence was investigated. CrAssphage prevalence was recorded using PCR and Sanger sequencing. The molecular diversity of crAssphage sequences was studied for viral gene segments from the major capsid protein (MCP) and membrane protein containing the peptidoglycan-binding domain (MP-PBD). KSU-WWTP and EMB-WWTP showed a higher prevalence of crAssphage (83.3%) than MN-WWTP (75%). Phylogenetic analysis of MCP and MP-PBD segments depicted a close relationship to the Japanese isolates. The MCP gene from the current study’s isolate WW/2M/SA/2022 depicted zero evolutionary divergence from 3057_98020, 2683_104905, and 4238_99953 isolates (d = 0.000) from Japan. A significant influence of temporal variations on the prevalence of crAssphage was detected in the three WWTPs. CrAssphage displayed the highest prevalence at high temperatures (33–44 °C), low relative humidity (6–14%), and moderate wind speed (16–21 Km/h). The findings provided pioneering insights into crAssphage prevalence and its genetic diversity in WWTPs in Riyadh, Saudi Arabia

Human Adenovirus Detection and Genetic Characterization in Irrigation Water from the Riyadh Region, Saudi Arabia

Adenoviruses are considered one of the most persistent enteric pathogens that can penetrate entire aquifer matrices. An ongoing monitoring of irrigation water is essential to mitigate potential public health risks. We investigated the prevalence of human adenoviruses (HAdV) in the groundwater discharge basins of Aluraiji (AW-DB) and Diriyah (DW-DB) and in the irrigation water of Al Harriq (H-IW) and Al Hayer (AH-IW) from January to December 2021. The meteorological impact (temperature, relative humidity, and wind speed) on HAdV prevalence and molecular diversity was investigated by targeting a selected region of the Hexon gene. The samples were concentrated using the polyethylene glycol precipitation (PEG) method. HAdVs were detected using PCR and sequenced by Sanger sequencing, and phylogenetic analysis was performed. The highest HAdV prevalence was recorded in H-IW, AH-IW, and DW-DB (100%). HAdV sequences were found to be closely related to species F (type 41) with a predominance of the 00-2B64 sequence (86.4%). Phylogenetic analysis depicted a close relationship of this study’s isolate 00-2B64 to a Brazilian and Saudi isolate, whereas 08-2B64 was found to be related to a sequence from an AnNazim landfill (LF1; d = 0.00) from Riyadh, Saudi Arabia. A high HAdV prevalence was recorded at a temperature range of 19–28 °C, wind speed was recorded at a range of (16–20 km/h), and relative humidity was recorded at a range of (15–25%). Meteorological variations exhibited no significant effect on the prevalence of HAdVs. The findings provided data on HAdV prevalence and predominant species in the irrigation water of Riyadh, Saudi Arabia and presented information regarding the environmental effects of HAdV persistence. In public health contexts, this will help in the planning of disease control strategies

Greener Synthesis of Zinc Oxide Nanoparticles: Characterization and Multifaceted Applications

Nanoparticles (NPs) have unique properties compared to their bulk counterparts, and they have potentials for various applications in many fields of life science. Green-synthesized NPs have garnered considerable interest due to their inherent features such as rapidity, eco-friendliness and cost-effectiveness. Zinc oxide nanoparticles (ZnO NPs) were synthesized using an aqueous extract of Kalanchoe blossfeldiana as a reducing agent. The resulting nanoparticles were characterized via X-ray diffraction (XRD), dynamic light scattering (DLS), UV-Vis spectroscopy, photoluminescence (PL), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The antimicrobial potential of the synthesized ZnO NPs against bacterial and fungal strains was examined by the disk diffusion method, and they showed a promising antibacterial and antifungal potential. The catalytic activity of the synthesized ZnO NPs in reducing methylene blue (MB) and eosin was studied via UV-Vis spectroscopy. The decolorization percentages of the MB and Eosin Y dyes were 84% and 94%, respectively, which indicate an efficient degradation of the ZnO NPs. In addition, the cytotoxic activity of the ZnO NPs on the HeLa cell line was evaluated via in vitro assay. The MTT assay results demonstrate a potent cytotoxic effect of the ZnO NPs against the HeLa cancer cell line

Increased Prevalence of EBV Infection in Nasopharyngeal Carcinoma Patients: A Six-Year Cross-Sectional Study

Epstein Barr Virus (EBV) is implicated in the carcinogenesis of nasopharyngeal carcinoma (NPC) and currently associated with at least 1% of global cancers. The differential prognosis analysis of NPC in EBV genotypes remains to be elucidated. Medical, radiological, pathological, and laboratory reports of 146 NPC patients were collected retrospectively over a 6-year period between 2015 and 2020. From the pathology archives, DNA was extracted from tumor blocks and used for EBV nuclear antigen 3C (EBNA-3C) genotyping by nested polymerase chain reaction (PCR). We found a high prevalence of 96% of EBV infection in NPC patients with a predominance of genotype I detected in 73% of NPC samples. Histopathological examination showed that most of the NPC patients were in the advanced stages of cancer: stage III (38.4%) or stage IV-B (37.7%). Only keratinized squamous cell carcinoma was significantly higher in EBV negative NPC patients compared with those who were EBV positive (OR = 0.01, 95%CI = (0.004–0.32; p = 0.009)), whereas the majority of patients (91.8%) had undifferentiated, non-keratinizing squamous cell carcinoma, followed by differentiated, non-keratinizing squamous cell carcinoma (7.5%). Although NPC had metastasized to 16% of other body sites, it was not associated with EBV infection, except for lung metastasis. A statistically significant reverse association was observed between EBV infection and lung metastasis (OR = 0.07, 95%CI = (0.01–0.51; p = 0.008)). Although 13% of NPC patients died, the overall survival (OS) mean time was 5.59 years. Given the high prevalence of EBV-associated NPC in our population, Saudi could be considered as an area with a high incidence of EBV-associated NPC with a predominance of EBV genotype I. A future multi-center study with a larger sample size is needed to assess the true burden of EBV-associated NPC in Saudi Arabia