Physicochemical and Microstructural Characterization of Injectable Load-Bearing Calcium Phosphate Scaffold

Injectable load-bearing calcium phosphate scaffolds are synthesized using rod-like mannitol grains as porogen. These degradable injectable strong porous scaffolds, prepared by calcium phosphate cement, could represent a valid solution to achieve adequate porosity requirements while providing adequate support in load-bearing applications. The proposed process for preparing porous injectable scaffolds is as quick and versatile as conventional technologies. Using this method, porous CDHA-based calcium phosphate scaffolds with macropores sizes ranging from 70 to 300 μm, micropores ranging from 5 to 30 μm, and 30% open macroporosity were prepared. The setting time of the prepared scaffolds was 15 minutes. Also their compressive strength and e-modulus, 4.9 MPa and 400 MPa, respectively, were comparable with those of the cancellous bone. Finally, the bioactivity of the scaffolds was confirmed by cell growth with cytoplasmic extensions in the scaffolds in culture, demonstrating that the scaffold has a potential for MSC seeding and growth architecture. This combination of an interconnected macroporous structure with pore size suitable for the promotion of cell seeding and proliferation, plus adequate mechanical features, represents a porous scaffold which is a promising candidate for bone tissue engineering

Conspiracy Beliefs Are Associated with Lower Knowledge and Higher Anxiety Levels Regarding COVID-19 among Students at the University of Jordan

The world has been afflicted heavily by the burden of coronavirus disease 2019 (COVID-19) that overwhelmed health care systems and caused severe economic and educational deficits, in addition to anxiety among the public. The main aim of this study was to evaluate the mutual effects of belief that the pandemic was the result of a conspiracy on knowledge and anxiety levels among students at the University of Jordan (UJ). An electronic-based survey was conducted between 29 March, 2020 and 31 March, 2020. The targeted population involved all undergraduate and postgraduate students from the health, scientific and humanities schools at UJ. Survey sections included 26 items on: socio-demographic information, knowledge and sources of information about the disease, attitude towards the false notion that COVID-19 stemmed from a conspiracy and items to assess the anxiety level among students during the quarantine period. The total number of participants was 1540 students. The mean age of study participants was 22 years and females predominated the study population (n = 1145, 74.4%). The majority of participants perceived the disease as moderately dangerous (n = 1079, 70.1%). Males, Jordanians and participants with lower income were more inclined to feel that COVID-19 is very dangerous. A lower level of knowledge and a higher level of anxiety about COVID-19 were associated with the belief that the disease is part of a conspiracy. Females and participants with lower income were more likely to believe that the disease is related to conspiracy. Belief in conspiracy regarding the origin of COVID-19 was associated with misinformation about the availability of a vaccine and the therapeutic use of antibiotics for COVID-19 treatment. The Ministry of Health in Jordan was the most common source of information about COVID-19 reported by the participants (n = 1018). The false belief that COVID-19 was the result of a global conspiracy could be the consequence of a lower level of knowledge about the virus and could lead to a higher level of anxiety, which should be considered in the awareness tools of various media platforms about the current pandemic

Prevalence of Bacterial Lower Respiratory Tract Infections at a Tertiary Hospital in Jordan

Background: Lower respiratory tract infections (LRTI) are a major cause of morbidity and mortality globally. The World Health Organization (WHO) estimates that LRTI are the most common global cause of death from infectious diseases.  However, the specific etiologic agent associated with LRTI is often unknown. Aims: We determined the bacterial infections and seasonal patterns associated with LRTI among hospitalized cases at Jordan University Hospital (JUH) for a period of five years. Methods: We conducted a multi-year study among hospitalized patients in Jordan on LRTI-associated bacterial etiology. Results: We found bacterial infections among 105 (21.1%) out of 495 LRTI patients. The most frequently identified bacteria in the LRTI patients were Staphylococcus aureus (7.7%) followed by Pseudomonas aeruginosa (5.1%). Most of the LRTI patients (95.2%) had at least one chronic disease and many were admitted to the Intensive Care Unit (16.8%). Of the 18 (3.64%) patients with LRTI who died at the hospital, 2 had a bacterial infection. We noticed a seasonal pattern of bacterial infections, with the highest prevalence during the winter months. Conclusions: Our findings suggest that early identification of bacterial agents and control of chronic disease may improve clinical management and reduce morbidity and mortality from LRTI

The Etiology of Viral Lower Respiratory Tract Infections at a Tertiary Hospital in Jordan over Five Years

Background Lower respiratory tract infection (LRTI) is the most common condition treated in primary care and is considered the third leading cause of death worldwide. The objective of our study is to determine the etiological agents that cause viral LRTI in Jordan, aiming to help physicians to choose the appropriate treatment strategy. Materials and Methods We conducted a retrospective study on patients who were admitted with the diagnosis of LRTI between January, 2011 and January, 2016. We used Fast-track Diagnostics (FTD)® Respiratory 21 Kit (Fast-track Diagnostics, Luxembourg) real-time PCR to determine the viral etiology of LRTI, and we investigated pandemic H1N1 2009 swine flu virus using rapid test PCR. Results This study involved 495 patients with a mean age of 57.79 ± 18.43 years. The causative agents were identified in 157 patients out of 495 patients (31.7%). FTD real-time PCR was done for 170 patients, and the test was positive for seasonal Influenza A virus in 7.1% of patients, influenza B in 4.1%, RSV in 4.7%, metapneumovirus in 4.1%, adenovirus in 4.1%, corona 229E/NL63 in 4.1%, parainfluenza virus in 7.6%, and rhinovirus in 3.5%. The percent of cases who were positive for pandemic H1N1 2009 swine flu virus was 4.2%. The rate of ICU admission was 16.8%, and the mortality rate of LRTI was as low as 3.64%. Conclusions Viral LRTI is more common in winter season in Jordan, especially in January. Remarkably, Influenza A and Parainfluenza viruses were the main viral causative agents for LRTI in our study

Modelling of amyotrophic lateral sclerosis (ALS) using induced pluripotent stem cells (iPSC)

The hexanucleotide repeat expansion (HRE) mutation within C9orf72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Several hypotheses have been proposed for how the mutation contributes to pathogenicity, including the loss of C9orf72 gene function, RNA-mediate toxicity and the formation of toxic dipeptides by repeat-associated non-ATG (RAN) translation. Patient-specific iPSCs provide a promising tool for the study of the cellular and molecular mechanisms of human diseases in relevant cell types and discovering potential therapies. The CRISPR (clustered regularly interspaced short palindromic repeats)-Cas9-mediated homology directed repair (HDR) system represents an attractive approach for disease modelling and development of therapeutic strategies. In this thesis, iPSCs derived from ALS/FTD patient carrying the HRE mutation were generated and subsequently gene edited to remove a massive repeat expansion from the patient cells and replace it with the wild-type size of the repeats using HDR and a plasmid donor template. The successful genotypic correction of the mutation resulted in the normalization of the C9orf72 gene promoter methylation level and the gene variants RNA expression level. Removal of the mutation also resulted in abolition of sense and antisense RNA foci formation and reduction of DPRs accumulation. Furthermore, the repeat size correction also rescued the susceptibility of cells to Glutamate excitotoxicity, decreased the apoptotic cell death and stress granules formation under the baseline and stress conditions. This work provides a proof-of-principle that removal of the HRE can rescue ALS disease phenotypes and provides an evidence that HRE mutation is an attractive target for therapeutic strategies and drug screening, to block the underlying disease mechanisms.</p

Modelling of amyotrophic lateral sclerosis (ALS) using induced pluripotent stem cells (iPSC)

The hexanucleotide repeat expansion (HRE) mutation within C9orf72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Several hypotheses have been proposed for how the mutation contributes to pathogenicity, including the loss of C9orf72 gene function, RNA-mediate toxicity and the formation of toxic dipeptides by repeat-associated non-ATG (RAN) translation. Patient-specific iPSCs provide a promising tool for the study of the cellular and molecular mechanisms of human diseases in relevant cell types and discovering potential therapies. The CRISPR (clustered regularly interspaced short palindromic repeats)-Cas9-mediated homology directed repair (HDR) system represents an attractive approach for disease modelling and development of therapeutic strategies. In this thesis, iPSCs derived from ALS/FTD patient carrying the HRE mutation were generated and subsequently gene edited to remove a massive repeat expansion from the patient cells and replace it with the wild-type size of the repeats using HDR and a plasmid donor template. The successful genotypic correction of the mutation resulted in the normalization of the C9orf72 gene promoter methylation level and the gene variants RNA expression level. Removal of the mutation also resulted in abolition of sense and antisense RNA foci formation and reduction of DPRs accumulation. Furthermore, the repeat size correction also rescued the susceptibility of cells to Glutamate excitotoxicity, decreased the apoptotic cell death and stress granules formation under the baseline and stress conditions. This work provides a proof-of-principle that removal of the HRE can rescue ALS disease phenotypes and provides an evidence that HRE mutation is an attractive target for therapeutic strategies and drug screening, to block the underlying disease mechanisms.</p

Temporal increase in D614G mutation of SARS-CoV-2 in the Middle East and North Africa

Background: Phylogeny construction can help to reveal evolutionary relatedness among molecular sequences. The spike (S) gene of SARS-CoV-2 is the subject of an immune selective pressure which increases the variability in such region. This study aimed to identify mutations in the S gene among SARS-CoV-2 sequences collected in the Middle East and North Africa (MENA), focusing on the D614G mutation, that has a presumed fitness advantage. Another aim was to analyze the S gene sequences phylogenetically. Methods: The SARS-CoV-2 S gene sequences collected in the MENA were retrieved from the GISAID public database, together with its metadata. Mutation analysis was conducted in Molecular Evolutionary Genetics Analysis software. Phylogenetic analysis was done using maximum likelihood (ML) and Bayesian methods. Result: A total of 553 MENA sequences were analyzed and the most frequent S gene mutations included: D614G = 435, Q677H = 8, and V6F = 5. A significant increase in the proportion of D614G was noticed from (63.0%) in February 2020, to (98.5%) in June 2020 (p < 0.001). Two large phylogenetic clusters were identified via ML analysis, which showed an evidence of inter-country mixing of sequences, which dated back to February 8, 2020 and March 15, 2020 (median estimates). The mean evolutionary rate for SARS-CoV-2 was about 6.5 × 10−3 substitutions/site/year based on large clusters' Bayesian analyses. Conclusions: The D614G mutation appeared to be taking over the COVID-19 infections in the MENA. Bayesian analysis suggested that SARS-CoV-2 might have been circulating in MENA earlier than previously reported. Phylogeny; Trend; COVID-19; MENA; Jordan; Oman; Egypt; Iran; Saudi Arabia; Morocco

Trends in Antimicrobial Drug Resistance of Streptococcus pneumoniae Isolates at Jordan University Hospital (2000–2018)

Antimicrobial drug resistance (AMR) in pneumococci complicates the treatment of serious pneumococcal infections. Country-specific AMR patterns can help to establish guidelines for empiric therapy. The aim of the current study was to analyze the distribution of AMR among Streptococcus pneumoniae isolates at Jordan University Hospital (JUH) during 2000–2018. Paper-based and electronic clinical data registry records from 2000 to 2018 were retrospectively analyzed to study the AMR among pneumococcal isolates at JUH. Temporal trend analysis was done using two-tailed linear-by-linear test for association. The total number of unique pneumococcal isolates that were identified was 556, of which 544 isolates had antimicrobial susceptibility testing results. The most frequent specimens were eye (n = 117, 21.0%), bloodstream (n = 93, 16.7%) and sputum (n = 81, 14.6%). Invasive infections represented 23.6% of all unique isolates. The overall susceptibility of S. pneumoniae isolates during the study period to different antimicrobials was: 100% to vancomycin, 97.7% to ceftriaxone, 97.1% to cefotaxime, 94.9% to chloramphenicol, 89.7% to penicillin, 83.8% to levofloxacin, 67.7% to clindamycin and 52.1% to erythromycin. The prevalence of multi-drug resistance (MDR) was 8.6% (95% confidence interval: 6.4–11.5%). Trend analysis showed an increase in the prevalence of non-susceptibility to erythromycin, clindamycin and levofloxacin (p < 0.001). MDR prevalence increased from 1.6% in the first quarter to 14.6% in the fourth quarter (p < 0.001). The incidence of invasive infections declined over the study period (p < 0.001). The increase in the prevalence of AMR and MDR among pneumococcal isolates in Jordan demands judicious use of antimicrobials and regular surveillance of resistance

Fabrication of porous bioceramics for bone tissue applications using luffa cylindrical fibres (LCF) as template

Three-dimensionally ordered macroporous biomaterials containing hydroxyapatite were synthesized using natural luffa cylindrical fibres (with diameter of 100–400 µm) as templates. The preliminary evaluation of this novel method for production of porous bioceramics showed promising potential applications in bone tissue engineering. The produced bioceramics were subjected to microstructural, physical, mechanical, and in vitro characterisation. Mercury intrusion porosimetry, supported by SEM analysis, showed the presence of bimodal porosity (smaller pores with diameters of 10 to 30 µm and cylindrical macropores with diameters from 100 to 400 µm) and 60% of the interconnected porosity. These porous calcium phosphate ceramics proved to be bioactive and exhibited mechanical properties comparable to those of natural spongy bones with compressive strength up to 3 MPa and elastic modulus in compression around 0.05 GPa. In vitro characterization of the porous ceramics showed cells attaching to the apatite crystals that make up the scaffold matrix. Cell adhesion resulted in elongated and highly stretched cells within the macropores with focal adhesion points on the scaffolds. Moreover, the cells adhered to the calcium phosphate cement (CPC) and developed cytoplasmic extensions as shown by SEM imagery. Their proliferation in the scaffolds in culture demonstrates that the scaffold architecture is suitable for Mesenchymal stem cells seeding and growth

KRAS and NRAS mutational gene profile of metastatic colorectal cancer patients in Jordan.

BACKGROUND:A constitutively active RAS protein in the absence of stimulation of the epidermal growth factor receptor (EGFR) is the result of mutations in KRAS and NRAS genes. Mutations in the KRAS exon 2 and outside exon 2 have been found to predict the resistance to anti-EGFR monoclonal therapy. A substantial proportion of metastatic colorectal cancer cases (mCRC) exhibit RAS mutations outside KRAS exon 2, particularly in KRAS exon 3 and 4 and NRAS exons 2 and 3. No data about RAS mutations outside KRAS exon 2 are available for Jordanian patients with mCRC. We aim to study the molecular spectrum, frequency, and distribution pattern of KRAS and NRAS mutations in Jordanian patients with mCRC. METHODS:A cohort of 190 Jordanian metastatic colorectal cancer patients were enrolled in the trial. We detected mutations in exon 2 of the KRAS and NRAS gene as well as mutations outside of exon 2 using the StripAssay technique. The KRAS StripAssay covered 29 mutations and 22 NRAS mutations. RESULTS:Mutations were observed in 92 (48.42%) cases, and KRAS exon 2 mutations accounted for 76 cases (83.69%). KRAS G12D was the most common mutation, occurring in 18 cases, followed by KRAS G12A in 16 cases, and G12T in 13 cases. Mutations outside of KRAS exon 2 represented 16.3% of the mutated cases. Among those, 6 cases (6.48%) carried mutations in NRAS exon 2 and 3, and 10 cases (10.87%) in KRAS exon 3 and 4. CONCLUSION:The frequency of NRAS and KRAS mutations outside of exon 2 appears to be higher in Jordanian patients in comparison with patients from western countries. KRAS mutations outside of exon 2 should be tested routinely to identify patients who should not be treated with anti-EGFR antibodies