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1.
J Infect Public Health ; 17(2): 245-253, 2024 Feb.
Article En | MEDLINE | ID: mdl-38141544

BACKGROUND: COVID-19 has killed over 6 million people worldwide, making it the worst global health disaster since the 1918 influenza pandemic. Experts have worked to establish the source, track and analyse the disease, and produce treatment and preventative guidelines. Inactivated vaccines have little evidence of efficacy compared to mRNA and adenoviral vector vaccines; however, three doses of both mRNA and inactivated vaccines appear to provide significant and lasting protection against severe disease and mortality. This study examines inactivated vaccine effectiveness data by disease status, age, gender, primary immunisation, booster doses, and SARS-CoV2 virus types. METHODS: We conducted a quantitative epidemiological meta-analysis study to assess the vaccine effectiveness of inactivated COVID-19 vaccines. Data extraction was performed on the selected studies, and data analysis was conducted using a random-effects model to determine consolidated assessments of vaccine effectiveness. Subgroup analyses were conducted for gender, age, disease level, and vaccine status, and sensitivity analyses were conducted to assess the robustness of the results. RESULTS: The overall effect size of inactivated COVID-19 vaccinations was statistically significant (p-value<0.05), suggesting that complete vaccination should be the primary method of vaccination. Partial vaccination was associated with lower levels of vaccine effectiveness (70.18 95% CI 57.33-83.02) than complete vaccination (79.52 95% CI 67.88-91.71)) and booster vaccination (84.22 95% CI 74.34-94.10), suggesting that it is essential to finish the recommended vaccine series and receive booster doses. Fig.-3: Partially vaccinated individuals showed a vaccine effect size of 70.18 (95% CI 57.33-83.02), indicating that the vaccine was moderately effective in preventing COVID-19 among this group. Fully vaccinated individuals showed a vaccine effect size of 79.52 (95% CI 67.88-91.71), indicating a higher level of vaccine effectiveness. Finally, booster-vaccinated individuals showed a vaccine effect size of 84.22 (95% CI 74.34-94.10), indicating the highest level of vaccine effectiveness. CONCLUSION: Inactivated COVID-19 vaccines are highly effective in preventing COVID-19, and complete vaccination and booster vaccination are associated with higher levels of vaccine effectiveness compared to partial vaccination. These findings highlight the importance of completing the recommended vaccine series and receiving booster doses to provide greater protection against COVID-19.


COVID-19 Vaccines , COVID-19 , Humans , COVID-19/prevention & control , RNA, Viral , SARS-CoV-2 , RNA, Messenger , Vaccines, Inactivated
2.
J Epidemiol Glob Health ; 13(4): 740-750, 2023 Dec.
Article En | MEDLINE | ID: mdl-37665505

INTRODUCTION: Multiple studies investigated the endurance and occurrence of symptoms three months after SARS-CoV-2 infection. This study examines the possible effects of COVID-19 vaccination on the persistence of post-recovery symptoms. PATIENTS AND METHODS: A cross-sectional survey was conducted in Saudi Arabia to evaluate 14 prevalent long COVID-19 symptoms among vaccinated individuals. Patients self-reported their acute COVID-19 experience, demographic information, chronic conditions, vaccine history, and persistent symptoms. RESULTS: Of the 484 patients, four respondents were excluded from the study as they had not received the vaccine, and 111 (23.1%) were vaccinated but did not get infected and were also excluded. The remaining 369 (76.9%) reported COVID-19 and a vaccination and thus they were included in the study. The occurrence of post-COVID-19 symptoms was reported in 59 (16.1%) for ≤ 3 months, 202 (54.8%) experienced persistent symptoms 3-6 months, and 108 (29.1%) reported symptoms lasting > 6 months. In relation to age group, persistent symptoms 3-6 months after recovery was more common in those > 50 years and symptoms lasting > 6 months were more common in 30-50 years of age (p < 0.001). Persistence of symptoms for 3-6 months was more common in those who were infected prior to vaccination compared to those who were infected after vaccination (P < 0.001). Of the included patients, 323 (87.5%) rated their health as good, 41 (11.1%) considered it fair, and 5 (1.4%) described their well-being as poor or terrible. CONCLUSION: The study provides information of persistent symptoms in vaccinated individuals who had recovered from COVID-19 and highlights the need for targeted interventions to alleviate post-COVID-19 symptoms. The study is limited by its reliance on self-reported data and potential selection bias. Future research is needed to understand the mechanisms underlying persistent symptoms in vaccinated individuals and to identify effective interventions for long COVID.


COVID-19 , Post-Acute COVID-19 Syndrome , Humans , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Cross-Sectional Studies , Post-Acute COVID-19 Syndrome/diagnosis , Post-Acute COVID-19 Syndrome/epidemiology , Saudi Arabia/epidemiology
3.
Cureus ; 15(4): e37532, 2023 Apr.
Article En | MEDLINE | ID: mdl-37187629

Background Children's exposure to different trace elements in their air, water, and food or even present in paints or toys can affect their intelligence quotient (IQ) score. However, this correlation needs to be analyzed and evaluated in different contexts. This study aimed to investigate the associations between airborne concentrations of lead (Pb), manganese (Mn), cadmium (Cd), chromium (Cr), and arsenic (As) and intellectual function in school-age children in Makkah, Kingdom of Saudi Arabia. Methodology Our cohort study aimed to explore the link between exposure to various trace elements in the surrounding air and the IQ scores of children residing in the vicinity of Makkah. We included 430 children in the study and collected information about demographic and lifestyle factors using a structured questionnaire. We employed a mini volume sampler (MiniVol, AirMetrics, Springfield, OR, USA) to collect 24-hour PM10 samples from five locations in Makkah, representing various residential areas with small-to-medium industrial activities and traffic load. We analyzed the samples for Pb, Mn, Cd, Cr, and As concentrations using inductively coupled plasma-mass spectrometry with Perkin Elmer 7300 (Perkin Elmer, Waltham, MA, USA). The combined impact of heavy metals on continuous outcomes was assessed using the Bayesian kernel machine regression model. Results The mean atmospheric concentrations of Pb, Mn, Cd, Cr, and As in summer were 0.093, 0.006, 0.36, 0.15, and 0.017 µg/m3, respectively, while in winter, they were 0.004, 0.003, 0.12, 0.006, and 0.01 µg/m3, respectively. The findings of our study revealed that children's IQ scores were independently associated with co-exposure to the five metals, namely, Pb, Mn, Cd, Cr, and As. Conclusions This study demonstrates a link between combined exposure to five heavy metals (Pb, Mn, Cd, Cr, and As) and children's IQ scores. Regularly evaluating trace elements in children's biological samples is crucial to comprehend their effects on cognitive growth. To explore the possible future health risks of multimetal exposures and their interaction effects, it is imperative to conduct additional studies that involve repeated biological measurements of metal concentrations.

4.
Biomedicines ; 10(7)2022 Jul 09.
Article En | MEDLINE | ID: mdl-35884960

Oxidative stress is considered the main etiologic factor involved in inflammatory bowel disease (IBD). Integration of nanocarriers for natural therapeutic agents with antioxidant and anti-inflammatory potential is a novel promising candidate for curing IBD. Herein, the colonic antioxidant and anti-inflammatory effects of different concentrations of quercetin nanoparticles (QT-NPs) were evaluated using a dextran sulfate sodium (DSS)-induced colitis model. Following colitis induction, the efficacy and mechanistic actions of QT-NPs were evaluated by assessing lesion severity, molecular aids controlling oxidative stress and inflammatory response, and histopathological and immunohistochemistry examination of colonic tissues. Administration of QT-NPs, especially at higher concentrations, significantly reduced the disease activity index and values of fecal calprotectin marker compared to the colitic group. Colonic oxidant/antioxidant status (ROS, H2O2, MDA, SOD, CAT, GPX and TAC) was restored after treatment with higher concentrations of QT-NPs. Moreover, QT-NPs at levels of 20 mg/kg and, to a lesser extent, 15 mg/kg reduced Nrf2 and HO-1 gene expression, which was in line with decreasing the expression of iNOS and COX2 in colonic tissues. Higher concentrations of QT-NPs greatly downregulated pro-inflammatory cytokines; upregulated genes encoding occludin, MUC-2 and JAM; and restored the healthy architectures of colonic tissues. Taken together, these data suggest that QT-NPs could be a promising alternative to current IBD treatments.

5.
Pharmaceuticals (Basel) ; 15(3)2022 Mar 15.
Article En | MEDLINE | ID: mdl-35337154

Salmonella enterica serovar Typhimurium (S. typhimurium) is known for its intracellular survival, evading the robust inflammation and adaptive immune response of the host. The emergence of decreased ciprofloxacin (CIP) susceptibility (DCS) requires a prolonged antibiotic course with increased dosage, leading to threatening, adverse effects. Moreover, antibiotic-resistant bacteria can persist in biofilms, causing serious diseases. Hence, we validated the in vitro and in vivo efficacy of ciprofloxacin-loaded mesoporous silica nanoparticles (CIP-MSN) using a rat model of salmonella infection to compare the oral efficacy of 5 mg/kg body weight CIP-MSN and a traditional treatment regimen with 10 mg/kg CIP postinfection. Our results revealed that mesoporous silica particles can regulate the release rate of CIP with an MIC of 0.03125 mg/L against DCS S. typhimurium with a greater than 50% reduction of biofilm formation without significantly affecting the viable cells residing within the biofilm, and a sub-inhibitory concentration of CIP-MSN significantly reduced invA and FimA gene expressions. Furthermore, oral supplementation of CIP-MSN had an insignificant effect on all blood parameter values as well as on liver and kidney function parameters. MPO and NO activities that are key mediators of oxidative stress were abolished by CIP-MSN supplementation. Additionally, CIP-MSN supplementation has a promising role in attenuating the elevated secretion of pro-inflammatory cytokines and chemokines in serum from S. typhimurium-infected rats with a reduction in pro-apoptotic gene expression, resulting in reduced S. typhimurium-induced hepatic apoptosis. This counteracted the negative effects of the S. typhimurium challenge, as seen in a corrected histopathological picture of both the intestine and liver, along with increased bacterial clearance. We concluded that, compared with a normal ciprofloxacin treatment regime, MSN particles loaded with a half-dose of ciprofloxacin exhibited controlled release of the antibiotic, which can prolong the antibacterial effect.

6.
Infection ; 50(6): 1431-1439, 2022 Dec.
Article En | MEDLINE | ID: mdl-35294728

INTRODUCTION: Recent studies investigated the endurance of symptoms and occurrence of complications three months after SARS-CoV-2 infection. This study aims to examine the prevalence, variation, and severity of continual symptoms in the post-COVID-19 using a single-center questionnaire. METHODS: The questionnaire was distributed among population in Saudi Arabia who recovered from COVID-19 between April 1, 2020 and December 31, 2021. RESULTS: A total of 744 participants completed the questionnaire, 318 (42.8%) recovered less than 3 months, 75 (10.1%) recovered 3-6 months, while 351 (47.2%) recovered more than 6 months. About half of the participants 353 (47.5%) had incessant symptoms and of those patients, more than half had two or more symptoms. Common symptoms included fatigue 189 (25.4%), headache 118 (15.9%), and myalgia 63 (8.5%). Of the participants, 189 (21.4%) experienced continual symptoms including anxiety in 98 (13.2%) and depression in 70 (9.5%). CONCLUSION: The current study showed a high proportion of individuals with long-COVID-19 symptoms. Thus, proper assessment of the individuals in the post-recovery period can guide the patients to the relevant clinics for rehabilitation. Moreover, there is a great importance to decrease COVID-19 infection, populations should be targeted to boost vaccine efficiency.


COVID-19 , Humans , COVID-19/epidemiology , SARS-CoV-2 , Saudi Arabia/epidemiology , Anxiety/epidemiology , Post-Acute COVID-19 Syndrome
7.
Aquat Toxicol ; 242: 106054, 2022 Jan.
Article En | MEDLINE | ID: mdl-34923218

Contamination of aquatic systems with heavy metals (HM) is of great concern owing to their deleterious impact on living organism. The current research is focused on application of silica particles with new functionalized properties (magnetic silica; SiMag or Nanoporous silica; SiNPs) and their efficacy to mitigate lead (pb) toxicity in Nile tilapia. One thousand fingerlings were distributed: two control groups (negative; without pb toxicity (NC) positive (with pb toxicity) and other four groups received two silica sources (SiMag or SiNPs) with two levels (400 and 600 mg/kg diet) for 56 days then exposed to pb for 30 days. Before toxicity exposure, maximum growth, and most improved feed conversion ratio and biochemical parameters were noticed with higher SiMag or SiNPs levels. Serum antioxidant enzymes and their transcriptional levels in muscle and liver were boosted in groups received SiMag or SiNPs. After toxicity exposure, hematological and antioxidants biomarkers maintained at adequate levels in SiMag or SiNPs. Prominent reduction of residual pb in gills, liver, kidney, and muscle was observed in SiNPs then SiMag groups. Interestingly, the maximum down-regulation of P450, caspase-3 and HSP-70 and MT were observed in groups received 600 mg/kg diet of SiMag or SiNPs. The higher level of P53 in liver and gills was detected in PC, inversely reduced in SiMag or SiNPs. Severity of the histopathological alterations in examined organs greatly reduced in groups received SiMag or SiNPs, unlike it were induced in PC group. In conclusion, higher SiMag or SiNPs levels not only mitigate negatives impact of pb toxicity in fish but also ensure its safety for human consumption.


Cichlids , Lead , Nanoparticles , Silicon Dioxide , Water Pollutants, Chemical , Animals , Antioxidants/metabolism , Apoptosis , Bioaccumulation , Cichlids/metabolism , Lead/toxicity , Water Pollutants, Chemical/toxicity
8.
J Immunoassay Immunochem ; 40(2): 159-182, 2019.
Article En | MEDLINE | ID: mdl-30452306

The current study proposed that previously characterized individual antigenic proteins could represent potential replacement for conventional purified protein derivative (PPD) in tuberculosis skin testing when used in cocktails triggered by suitable TLR-stimulants that would provide the missing pro-inflammatory stimulus. Three different cocktails of previously selected antigens, including C1 (ESAT-6/CPF-10/MPB-83); C2 (ESAT-6/MPB-64/MPB-83); and C3 (CPF-10/MPB-64/MPB-83), were evaluated in vitro using lymphocytic proliferation and IFN-γ production assays, as well as mRNA and protein expression levels of TNF-α, IL-12p40, and IL-2 as pro-inflammatory molecules. C1 showed the highest significant induction of pro-inflammatory molecules as compared to other cocktails, yet still significantly lower than that induced by conventional PPD. Interestingly, inclusion of the synthetic Mycobacterium tuberculosis 19-kDa lipoprotein (Pam3Cys-SSNKSTTGSGETTTA) as a TLR-stimulant resulted in obvious augmentation of C1-induced pro-inflammatory molecules to levels comparable to that of PPD. In addition, skin testing using sensitized guinea pig model revealed comparable significant reaction to that of conventional PPD. ESAT-6/CPF-10/MPB-83 cocktail is suggested as a potential alternative skin-testing reagent when used in combination with the M. tuberculosis 19-kDa lipoprotein as a TLR-stimulant.


Antigens, Bacterial/immunology , Hypersensitivity, Delayed/immunology , Lipoproteins/immunology , Mycobacterium tuberculosis/immunology , Toll-Like Receptors/immunology , Animals , Guinea Pigs , Lipoproteins/chemical synthesis , Lipoproteins/chemistry , Tuberculin Test
9.
PLoS One ; 12(7): e0182144, 2017.
Article En | MEDLINE | ID: mdl-28759055

Two distinct type IV secretion systems (T4SSs) can be identified in certain Helicobacter pylori strains, encoded on mobile genetic elements termed tfs3 and tfs4. Although their function remains unknown, both have been implicated in clinical outcomes of H. pylori infection. Here we provide evidence that the Tfs3 T4SS is required for activity of the pro-inflammatory Ser/Thr kinase protein, CtkA, in a gastric epithelial cell infection model. Previously, purified recombinant CtkA protein has been shown to upregulate NF-kappaB signalling and induce TNF-alpha and IL-8 cytokine secretion from cultured macrophages suggesting that it may potentiate the H. pylori-mediated inflammatory response. In this study, we show that CtkA expressed from its native host, H. pylori has a similar capacity for stimulation of a pro-inflammatory response from gastric epithelial cells. CtkA interaction was found to be dependent upon a complement of tfs3 T4SS genes, but independent of the T4SSs encoded by either tfs4 or the cag pathogenicity island. Moreover, the availability of CtkA for host cell interaction was shown to be conditional upon the carboxyl-terminus of CtkA, encoding a putative conserved secretion signal common to other variably encoded Tfs3 proteins. Collectively, our observations indicate a role for the Tfs3 T4SS in CtkA-mediated pro-inflammatory signalling by H. pylori and identify CtkA as a likely Tfs3 T4SS secretion substrate.


Bacterial Proteins/metabolism , Helicobacter pylori/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , Type IV Secretion Systems/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Cell Line , Cytokines/genetics , Cytokines/metabolism , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Helicobacter pylori/genetics , Helicobacter pylori/pathogenicity , Humans , Protein Domains , Protein Serine-Threonine Kinases/chemistry , Protein Serine-Threonine Kinases/genetics , Type IV Secretion Systems/genetics
10.
J Biol Chem ; 288(37): 26385-96, 2013 Sep 13.
Article En | MEDLINE | ID: mdl-23900838

Four different type IV secretion systems are variously represented in the genomes of different Helicobacter pylori strains. Two of these, encoded by tfs3 and tfs4 gene clusters are contained within self-transmissible genomic islands. Although chromosomal excision of tfs4 circular intermediates is reported to be dependent upon the function of a tfs4-encoded XerD tyrosine-like recombinase, other factors required for transfer to a recipient cell have not been demonstrated. Here, we characterize the functional activity of a putative tfs4-encoded VirD2-like relaxase protein. Tfs4 VirD2 was purified as a fusion to maltose-binding protein and demonstrated to bind and nick both supercoiled duplex DNA and oligonucleotides in vitro in a manner dependent upon the presence of Mg(2+) but independently of any auxiliary proteins. Unusually, concentration-dependent nicking of duplex DNA appeared to require only transient protein-DNA interaction. Although phylogenetically distinct from established relaxase families, site-specific cleavage of oligonucleotides by Tfs4 VirD2 required the nick region sequence 5'-ATCCTG-3' common to transfer origins (oriT) recognized by MOBP conjugative relaxases. Cleavage resulted in covalent attachment of MBP-VirD2 to the 5'-cleaved end, consistent with conventional relaxase activity. Identification of an oriT-like sequence upstream of tfs4 virD2 and demonstration of VirD2 protein-protein interaction with a putative VirC1 relaxosome component indicate that transfer initiation of the tfs4 genomic island is analogous to mechanisms underlying mobilization of other integrated mobile elements, such as integrating conjugative elements, requiring site-specific targeting of relaxase activity to a cognate oriT sequence.


Bacterial Proteins/metabolism , Conjugation, Genetic , DNA Nucleotidyltransferases/metabolism , Genomic Islands , Helicobacter pylori/genetics , Amino Acid Sequence , Bacterial Proteins/genetics , DNA Nucleotidyltransferases/genetics , DNA, Bacterial/analysis , Escherichia coli/metabolism , Helicobacter pylori/metabolism , Molecular Sequence Data , Phylogeny , Plasmids/metabolism , Protein Structure, Tertiary , Sequence Homology, Amino Acid , Two-Hybrid System Techniques
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