Durability of COVID-19 humoral immunity post infection and different SARS-COV-2 vaccines.

BACKGROUND: The global challenge posed by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been a major concern for the healthcare sector in recent years. Healthcare workers have a relatively high risk of encountering COVID-19 patients, making protective immunity against SARS-CoV-2 is a priority for them. This study aims to evaluate the longitudinal measurement of SARS-CoV-2 IgG spike protein antibodies in healthcare workers (HCWs) after COVID-19 infection and after receiving the first and second doses of SARS-CoV-2 vaccines, including Pfizer-BioNTech (BNT162b2) and Oxford-AstraZeneca (AZD1222). METHODS: This longitudinal cohort study involved 311 healthcare workers working in two tertiary hospitals in Saudi Arabia. All participants were followed between July 2020 and July 2022 after completing the study questionnaire. A total of 3 ml of the blood samples were collected at four intervals: before/after vaccination. RESULTS: HCWs post-infection had lower mean SARS-CoV-2 IgG levels three months post-infection than post-vaccination. 92.2% had positive IgG levels two weeks after the first dose and reached 100% after the second dose. Over 98% had positive antibodies nine months after the second dose, regardless of vaccine type. The number of neutralizing antibodies decreased and was around 50% at nine months after the second dose. CONCLUSION: The results show different antibody patterns between infected and vaccinated HCWs. A high proportion of participants had positive antibodies after vaccination, with high levels persisting nine months after the second dose. Neutralizing antibodies decreased over time, with only about 50% of participants having positive antibodies nine months after the second dose. These results contribute to our understanding of immunity in healthcare workers and highlight the need for the continuous monitoring and possible booster strategies.

Identification of founder and novel mutations that cause congenital insensitivity to pain (CIP) in palestinian patients.

BACKGROUND: Congenital insensitivity to pain (CIP) is a rare autosomal recessive disorder characterized primarily by an inability to perceive physical pain from birth, resulting in the accumulation of bruising, inflammation, and fractures that affect patient's life expectancy. CIP has different forms including CIP and CIPA. CIP with Anhidrosis (CIPA) is the most common type of CIP, which is caused mainly by mutations in NTRK1 and NGF genes, and is characterized by mental retardation and the inability to sweat (Anhidrosis). Because of high consanguinity rates in Palestine, this rare disease appears to have a higher frequency than in other communities. However, there were no systematic studies to address the genetic factors that cause CIP in the Palestinian community. METHODS: In our study, we used Sanger and Whole exome sequencing to genotype members of five CIP-affected Palestinian families. RESULTS: Our results confirm the presence of the founder c.1860-1861insT mutation in the NTRK1 gene of Palestinian Bedouin CIPA patients. Furthermore, one CIPA family carried a missense c.2170 G > A (G724 S) mutation in exon 16 of the NTRK1 gene. Finally, a novel nonsense c.901 A > T mutation (K301*) was detected in exon 7 of the SCN9A gene in CIP without anhidrosis family. CONCLUSIONS: Our study revealed three mutations that cause CIP and CIPA in the Palestinian community, which can help in improving the process of diagnosis and genetic counseling and establishing protocols for the diagnosis and follow-up for the affected individuals. This is especially important given that early diagnosis and medical care interference can prevent unpleasant CIP and CIPA complications.

Comparative Metabolic Characterization of Extraintestinal Pathogenic Escherichia coli Blood Isolates from Saudi Arabia.

Background: The prevalence of bloodstream infections caused by extraintestinal pathogenic Escherichia coli (ExPEC) has increased substantially. E. coli ST131 is one of the dominant ExPEC clones among E. coli bacteremia population. Metabolism can trigger the pathogenesis of some bacterial isolates, and here we evaluated and compared the metabolic traits of E. coli bacteremia isolates including ß-lactamase (BL)/extended-spectrum ß-lactamase (ESBL)-positive and ESBL-negative isolates and ST131 and non-ST131 isolates. Methods: The metabolic profiles of thirty E. coli isolates, obtained from blood samples for hospitalized individuals at a tertiary healthcare facility in Riyadh, were determined using HiMedia carbohydrate test strips. The difference in the utilization ability between isolate groups was then statistically assessed. Results: Our data found that non-BL/ESBL producers were of low metabolic capacity compared with ESBL-positive isolates although the difference remained insignificant. Higher levels of utilization for some carbohydrates, such as fructose and trehalose, were detected among ST131 isolates when compared with non-ST131, and ST131 was also significantly associated with metabolizing rhamnose. The mean bio-score of both isolate groups was insignificant. We showed no link between metabolism and antimicrobial susceptibility profiles among tested blood isolates. Conclusion: ST131 blood isolates were slightly higher in their carbohydrate utilization activity than non-ST131. More importantly, ST131 isolates were significantly capable of metabolizing rhamnose. Future research should focus on the factors that might drive the success of major ExPEC clones such as ST131.

IL-35 and IL-37 are negatively correlated with high IgE production among children with asthma in Saudi Arabia.

BACKGROUND: Asthma is one of the most prevalent inflammatory disorders among children in Saudi Arabia. OBJECTIVE: This study aimed to determine the correlation between the serum levels of vitamin D, immunoglobulin E (IgE), and cytokine (interferon-gamma (IFN-γ), interleukin (IL)-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) in relation to the severity of disease in patients with asthma. METHODS: This case-control study was carried out at King Abdullah Specialist Children's Hospital, Saudi Arabia, and included 48 patients with asthma and 47 matched controls, aged 6-14 years. A validated questionnaire was administered to the participants, after which each patient with asthma underwent pulmonary function tests. The serum levels of vitamin D, IgE, IFN-γ, IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 of each participant were also measured. RESULTS: Patients with asthma demonstrated significantly higher IgE and cytokine (IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37) levels compared to the control group (p value < .001). The levels of IL-1ß, IL-4, IL-10, and IL-13 were consistently positively correlated with the serum levels of IgE among patients with asthma. However, the IgE levels in patients with asthma were consistently negatively correlated with IL-35 and IL-37. CONCLUSIONS: We found significantly higher levels of eosinophils, IgE, IL-1ß, IL-4, IL-6, IL-10, IL-13, IL-35, and IL-37 in patients with asthma compared to the controls, but no relationship between vitamin D and asthma.

Seroprevalence of SARS-CoV-2 among high-risk healthcare workers in a MERS-CoV endemic area.

INTRODUCTION: Healthcare workers (HCWs) in Saudi Arabia are a unique population who have had exposures to the Middle East Respiratory Syndrome coronavirus (MERS-CoV) and Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It follows that HCWs from this country could have pre-existingMERS-CoV antibodies that may either protect from coronavirus disease 2019 (COVID-19) infection or cause false SARS-CoV-2 seropositive results. In this article, we report the seroprevalence of MERS-CoV and SARS-CoV-2 among high-risk healthcare workers in Riyadh city, Saudi Arabia. METHODS: This is a cross-sectional study enrolling 420 high-risk HCWs who are physically in contact with COVID-19 patients in three tertiary hospitals in Riyadh city. The participants were recruited between the 1st of July to the end of December 2020. A 3 ml of the venous blood samples were collected and tested for the presence of IgG antibodies against the spike proteins of SARS-CoV-2 and MERS-CoV using enzyme-linked immunosorbent assay (ELISA). RESULTS: The overall prevalence of SARS-CoV-2 in high-risk HCWs was 14.8% based on SARS-CoV-2 IgG testing while only 7.4% were positive by Polymerase Chain Reaction (PCR) for viral RNA. Most of the SARS-CoV-2 seropositive HCWs had symptoms and the most frequent symptoms were body aches, fever, cough, loss of smell and taste, and headache. The seroprevalence of MERS-CoV IgG was 1% (4 participants) and only one participant had dual seropositivity against MERS-CoV and SARS-CoV-2. Three MERS-CoV positive samples (75%) turned to be negative after using in-house ELISA and none of the MERS-CoV seropositive samples had detectable neutralization activity. CONCLUSION: Our SARS-CoV-2 seroprevalence results were higher than reported regional seroprevalence studies. This finding was expected and similar to other international findings that targeted high-risk HCWs. Our results provide evidence that the SARS-CoV-2- seropositivity in Saudi Arabia similar to other countries was due to exposure to SARS-CoV-2 rather than MERS-CoV antibody.

Comparative phenotypic characterization identifies few differences in the metabolic capacity between Escherichia coli ST131 subclones.

BACKGROUND: Extraintestinal pathogenic Escherichia coli (ExPEC) is responsible for causing many infections such as urinary tract infections (UTIs). The current dissemination of the multidrug resistant (MDR) ExPEC clone, Escherichia coli sequence type 131 (E. coli ST131), poses a real threat to public health worldwide. This study aimed to determine and compare the metabolic capacity of a collection of ExPEC isolates including ST131, non-ST131 and various ST131 subclones, and sought to assess the association between antimicrobial resistance and metabolic capacity of ST131 isolates. METHODS: The metabolic activity of forty urine E. coli isolates, collected from in-patients hospitalized at tertiary hospital in Riyadh, was tested using KB009 Hi carbohydrate kit, and then statistically analysed to assess the difference in the metabolic profiles between ST131 and non-ST131 isolates, and between ST131 subclones. RESULTS: The data of this study found almost similar metabolic profiles between ST131 and non-ST131, suggesting that ST131 is not a metabolically unique clone of ExPEC. There was also no link between antimicrobial susceptibility profiles and high metabolic capacity of ST131 isolates. Testing the biochemical activity of isolates belonging to ST131 subclones found higher activity of H30 subclone than non-H30 isolates, however it revealed few significant differences between these subclones. CONCLUSION: This study demonstrated no difference in the metabolism of ST131 and non-ST131, although it uncovered the presence of few significant differences in the metabolic capacity between ST131 subclones. Carrying out whole-genome based studies on ST131 and its main subclones is essential to elucidate the genetic factors responsible for the success of particular ST131 subclones.

Microbial Diversity of Some Sabkha and Desert Sites in Saudi Arabia.

Several studies isolated fungal and bacterial species from extreme environments, such as Sabkha and hot deserts, as their natural habitat, some of which are of medicinal importance. Current research aimed investigating the microbial (fungi and bacteria) diversity and abundance in Sabkha and desert areas in Saudi Arabia. Soil samples from nine different geographical areas (Al-Aushazia lake, AlQasab, AlKasar, Tabuk, Al-Kharj, Al-Madina, Jubail, Taif and Abqaiq) were collected and cultured for microbial isolation. Isolated fungi and bacteria were identified by molecular techniques (PCR and sequencing). Based on 18S rDNA sequencing, 203 fungal species belonging to 33 genera were identified. The most common fungal genera were Fusarium, Alternaria, Chaetomium, Aspergillus Cochliobolus and Pencillium, while the most common species were Chaetomium globosum and Fusarium oxysporum. By 16S rDNA sequencing 22 bacterial species belonging to only two genera, Bacillus and Lactobacillus, were identified. The most commonly isolated bacterial species were Bacillus subtilis and Lactobacillus murinus. Some fungal species were confined to specific locations, such as Actinomyces elegans, Fusarium proliferatum, Gymnoascus reesii and Myzostoma spp. that were only isolated from Al-Aushazia soil. AlQasab soil had the highest microbial diversity among other areas with abundances of 23.5% and 4.4% of total fungi, and bacteria, respectively. Findings of this study show a higher degree of fungal diversity than that of bacteria in all studied areas. Further studies needed to investigate the connection between some isolated species and their habitat ecology, as well as to identify those of medicinal importance.

Prevalence and molecular characteristics of sequence type 131 clone among clinical uropathogenic Escherichia coli isolates in Riyadh, Saudi Arabia.

BACKGROUND: The antimicrobial resistance of extraintestinal pathogenic Escherichia coli (ExPEC) has progressively been reported worldwide. This resistance has been ascribed to global dissemination of a single E. coli clone, namely E. coli sequence type 131 (E. coli ST131). The main goal of this study is to determine the prevalence and molecular traits of ST131 and its subclones among E. coli clinical urine isolates in Riyadh, Saudi Arabia. METHODS: Sixty E. coli urine isolates, of different extended spectrum ß-lactamase (ESBL) carriage, were involved in this study. Molecular characterization was carried out to determine the ST131 status, phylogenetic groups and virulence carriage of these isolates. ST131 isolates were further tested to evaluate the prevalence of different phylogenetic groups, subclones and virulence carriage. RESULTS: Group B2 was the most common phylogroup from which E. coli isolates derived. Overall, 37 of 60 (61.7%) isolates belonged to ST131 clones. Of these, 19 (31.7%) isolates were from the H30 subclone, including 10 (16.7%) H30 non-Rx and 9 (15%) H30Rx. The remaining 18 (30%) ST131 isolates belonged to other non H30 subclones. H30 subclone was significantly higher in the virulence carriage in comparison to non H30 ST131 subclones. CONCLUSION: This study reported the prevalence and traits of clinical E. coli ST131 main subclones in Saudi Arabia. It also demonstrated the high prevalence of E. coli ST131 locally, and found different virulence genotypes and antimicrobial resistance phenotypes among ST131 subclones. In the future, preforming whole genome sequence-based studies on ST131 and its subclones is crucial to elucidate factors that drive the success of these organisms.

Morphological and molecular insights of a new species of trypanorhynchid cestode parasite, Nybelinia exostigmi, in the Narrowstripe cardinal fish Apogon exostigma.

Forty specimens of the Narrowstripe cardinal fish Apogon exostigma were examined for gastrointestinal helminthes, and 62.5% were infected with a new trypanorhynchid larval cestode parasite. The morphology of its larval stage was studied based on light and scanning electron microscopy. The data revealed plerocercoid larvae characterized by a pyriform body lined with prominent microtriches; the acraspedote scolex had four overlapping bothridia; four tentacles protruded through the pars bothridialis; the armature of the tentacles was homeocanthous, homeomorphous, and consisted of falcate compact rose-thorn-shaped tentacular hooks; four oval-shaped bulbs in pars bulbosa; and short appendix at terminal end of the body. Molecular analysis of the 18S rRNA sequences verified the taxonomy of this parasite and supported its morphology. We discovered that there was a close identity (up to 87%) with alternative species obtained for comparison from GenBank. The data also showed that there were high blast scores and low divergence values between this parasite and other Tentaculariidae species. The phyletic analysis showed that parasite sequences in conjunction with existing data places this trypanorhynchid species among the Tentaculariidae. This species is deeply embedded within genus Nybelinia with close relationships to Nybelinia queenslandensis as a putative sister taxon.

Morphological and molecular insights of a new species of trypanorhynchid cestode parasite, Nybelinia exostigmi, in the Narrowstripe cardinal fish Apogon exostigma / Abordagens morfológicas e moleculares de uma nova espécie de parasito cestóide tripanorrinquídeo, Nybelinia exostigmi, no peixe cardinal Narrowstripe Apogon exostigma

Abstract Forty specimens of the Narrowstripe cardinal fish Apogon exostigma were examined for gastrointestinal helminthes, and 62.5% were infected with a new trypanorhynchid larval cestode parasite. The morphology of its larval stage was studied based on light and scanning electron microscopy. The data revealed plerocercoid larvae characterized by a pyriform body lined with prominent microtriches; the acraspedote scolex had four overlapping bothridia; four tentacles protruded through the pars bothridialis; the armature of the tentacles was homeocanthous, homeomorphous, and consisted of falcate compact rose-thorn-shaped tentacular hooks; four oval-shaped bulbs in pars bulbosa; and short appendix at terminal end of the body. Molecular analysis of the 18S rRNA sequences verified the taxonomy of this parasite and supported its morphology. We discovered that there was a close identity (up to 87%) with alternative species obtained for comparison from GenBank. The data also showed that there were high blast scores and low divergence values between this parasite and other Tentaculariidae species. The phyletic analysis showed that parasite sequences in conjunction with existing data places this trypanorhynchid species among the Tentaculariidae. This species is deeply embedded within genus Nybelinia with close relationships to Nybelinia queenslandensis as a putative sister taxon.

Resumo Quarenta espécimes do peixe cardinal Apogon exostigma da Narrowstripe foram examinados para identificar helmintos gastrointestinais, destes 62,5% foram infectados com um novo parasito larval cestóide tripanorrinquídeo. A morfologia de seu estágio larval foi estudada na microscopia de luz e eletrônica de varredura. Os dados revelaram larvas plerocercoides caracterizadas por uma forma piriforme com um corpo revestido por microtrícinos proeminentes; o escolex acraspedótico tinha quatro sobreposições; quatro tentáculos se projetavam através da pars botridialis; a armadura dos tentáculos era homeocante, homeomorfa e consistia de ganchos tentaculares em forma de espinhos, em forma de falcão; quatro bulbos ovais em pars bulbosa; e apêndice curto na extremidade terminal do corpo. A análise molecular das sequências de RNAr 18S verificou a taxonomia desse parasita e apoiou sua morfologia. Descobrimos que havia uma identidade próxima (até 87%) com espécies alternativas obtidas para comparação do GenBank. Os dados também mostraram que houve altos escores de brusone e baixos valores de divergência entre este parasita e outras espécies de Tentaculariidae. A análise filética mostrou que as sequências de parasitas em conjunto com os dados existentes colocam esta espécie de tripanorimidídeo entre os Tentaculariidae. Esta espécie está profundamente enraizada no gênero Nybelinia, tendo relações próximas com Nybelinia queenslandensis como um putativo táxon irmão.

Prevalence of Multidrug Resistance and Extended-Spectrum ß-Lactamase Carriage of Clinical Uropathogenic Escherichia coli Isolates in Riyadh, Saudi Arabia.

The prevalence of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-producing E. coli) has recently increased worldwide. This study aims at determining the antimicrobial susceptibility patterns of a collection of clinical E. coli urine isolates and evaluating the ESBL carriage of these isolates at phenotypic and genotypic levels. A total of 100 E. coli urine isolates were collected at a tertiary healthcare centre in Riyadh from January 2018 to March 2018. Antimicrobial susceptibility testing was carried out for all isolates. ESBL production was characterized at phenotypic and genotypic levels using double-disc synergy test and polymerase chain reaction, respectively. Detection of different ESBL variants was performed using DNA sequencing. Of 100 E. coli isolates, 67 were associated with multidrug resistance (MDR) phenotype. All isolates showed variable resistance levels to all antibiotics used here expect to imipenem, where they were all imipenem-sensitive. 33 out of 100 E. coli isolates were positive for ESBLs by phenotypic and genotypic methods. Among all ESBL-positive E. coli isolates, the CTX-M was the most prevalent ESBL type (31/33 isolates; 93.94%). CTX-M-15 variant was detected in all isolates associated with CTX-M carriage. Multiple ESBL gene carriage was detected in 15/33 isolates (45.45%), where 11 (33.33%) isolates produced two different ESBL types while 4 isolates (12.12%) associated with carrying three different ESBL types. Our study documented the high antimicrobial resistance of ESBL-producing E. coli to many front-line antibiotics currently used to treat UTI patients, and this implies the need to continuously revise the local guidelines used for optimal empirical therapy for UTI patients. It also showed the high prevalence of ESBL carriage in E. coli urine isolates, with CTX-M-15 being the most predominant CTX-M variant.

Association analysis between four vitamin D receptor gene polymorphisms and developmental dysplasia of the hip.

Developmental dysplasia of the hip (DDH) is a congenital condition characterized by abnormality in acetabulum size and/or shape. The incidence rate of DDH differs between different populations with risk factors including positive family history, breech presentation, sex, firstborn status, side of the hip, mode of delivery and oligohydramnios. It is recognized that DDH has a genetic component that exhibit autosomal dominant patterns. Many candidate genes have been studied and found to be associated with the disease; most of them are normally involved in cartilage development and joint metabolism. In this study, the association of four single-nucleotide polymorphisms (SNPs) (rs731236, rs1544410, rs7975232 and rs2228570) in the vitamin D receptor (VDR) gene was studied by a case-control analysis. The study sample involves 50 cases with confirmed DDH presentation and 50 nonDDH controls. SNPs were genotyped using conventional polymerase chain reaction (PCR) and restriction fragment-length polymorphism (RFLP) techniques. Genotype and allele frequencies were analysed using SPSS software. No significant associations were found between the VDR polymorphisms analysed and DDH. Further work need to be performed using genomewide analysis to elucidate the genetic basis of DDH.