Integrated immunoinformatics and subtractive proteomics approach for multi-epitope vaccine designing to combat S. pneumoniae TIGR4.

Streptococcus pneumoniae is one of the major precarious pathogens accountable for over 1.2 million fatalities annually. The key drivers for pneumococcal vaccine development involve high morbidity and mortality in over one million cases, especially in very young children and the elderly. In this study, immunoinformatics was integrated with subtractive proteomics to find antigenic proteins for designing a multi-epitope vaccine against S. pneumoniae. As prospective vaccine targets, the developed pipeline identified two antigenic proteins, i.e., penicillin-binding protein and ATP synthase subunit. Several immunoinformatics and bioinformatics resources were used to forecast T- and B-cell epitopes from specific proteins. By employing a mixture of five cytotoxic T-cell lymphocytes, six helper T-cell lymphocytes, and seven linear B-cell lymphocyte epitopes, a 392 amino acid-long vaccine was designed. To enhance immune responses, the designed vaccine was coupled with a cholera enterotoxin subunit B adjuvant. The designed vaccine was highly antigenic, non-allergenic, and stable for human usage. The stability of the vaccine with toll-like receptor-4 was evaluated by molecular docking and molecular dynamic simulation. In addition, immunological simulation was performed to test its real-world potency. The vaccine codon was then cloned in silico. Overall, this study paves the way for the development of a multi-epitope S. pneumoniae vaccine under laboratory conditions. Furthermore, the current findings warrant for the experimental validation of the final multi-epitope vaccine construct to demonstrate its immunological reinforcing capability and clinical applicability.

Isolation and Detection of Drug-Resistant Bacterial Pathogens in Postoperative Wound Infections at a Tertiary Care Hospital in Saudi Arabia.

Background: Surgical site infections (SSIs), especially when caused by multidrug-resistant (MDR) bacteria, are a major healthcare concern worldwide. For optimal treatment and prevention of antimicrobial resistance, it is important for clinicians to be aware of local drug-resistant bacterial pathogens that cause SSIs. Objective: To determine the frequency patterns of drug-resistant bacterial strains causing SSIs at a tertiary care hospital in Saudi Arabia. Methods: This retrospective study was conducted at the Microbiology laboratory of Al-Noor Specialist Hospital, Makkah, Saudi Arabia, and included wound swab samples from all cases of SSI between January 01, 2017, and December 31, 2021. The swabs were processed for the identification of bacterial strains and their resistance pattern to antibiotics according to the Clinical and Laboratory Standards Institute. Results: A total of 5409 wound swabs were analyzed, of which 3604 samples (66.6%) were from male. Most samples were from the Department of Surgery (43.3%). A total of 14 bacterial strains were isolated, of which 9 were Gram-negative bacteria. The most common isolates were Klebsiella pneumoniae, followed by Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), and vancomycin-resistant S. aureus (VRSA). In terms of MDR in 2021, the highest rate of carbapenem-resistance was in A. baumannii (97%). MDR was as follows: A. baumannii, 97%; K. pneumoniae, 81%; E. coli, 71%; MRSA, 60%; P. aeruginosa, 33%; VRE, 22%; and VRSA, 2%. Conclusion: This study showed that in the city of Makkah, Saudi Arabia, the rates of MDR bacteria are high, with the majority being Gram-negative.

Antimicrobial Resistance Pattern of Pseudomonas aeruginosa: An 11-Year Experience in a Tertiary Care Hospital in Makkah, Saudi Arabia.

Purpose: Pseudomonas aeruginosa (P. aeruginosa) is a common causative pathogen in healthcare settings and displays increasing levels of resistance to common antimicrobial drugs. Its capacity to resist has been reported in multiple locations across the world. This study evaluates current levels of antibiotic resistance and seeks to understand antibiotic resistance patterns in the context of the clinical isolates of P. aeruginosa. Methods: All clinical isolates were cultured at 37 °C for 24 h in different media: blood sheep agar, McConkey agar, and cystine-lactose-electrolyte-deficient agar (CLED), bacterial identification and antibiotic susceptibility patterns were determined using the Vitek-2 (bioMérieux) automated system. Results: In total, there were 61,029 patient specimens, of which 5534 were identified as non-duplicated P. aeruginosa clinical isolates, most being from males aged over 60 years. The research findings revealed that the maximum antibiotic resistance associated with P. aeruginosa isolates was found in colistin (97%), which was followed by piperacillin/tazobactam (75.8%). The maximum resistance rates in P. aeruginosa isolates were found in relation to cefepime (42.7%,) which was followed by ciprofloxacin (34.3%). Conclusion: The antibiotic resistance rate during the first six years of the research period was notably higher than in the last years, due to the application of infection control protocols and strict policies to control antibiotic prescriptions in all Saudi hospitals.

Green synthesis of MgO nanoparticles and its antibacterial properties.

Magnesium oxide nanostructured particles (NP) were prepared using a simple solution combustion technique using different leaf extracts such as Mangifera indica (Mango - Ma), Azadirachta indica (Neem-Ne), and Carica papaya (Papaya-Pa) as surfactants. The highly crystalline phase of MgO nanostructures was confirmed by PXRD and FTIR studies for 2 h 500°C calcined samples. To analyze the characteristics of obtained material-MaNP, NeNP, and PaNP for dosimetry applications, thermoluminescence (TL) studies were carried out for Co-60 gamma rays irradiated samples in the dose range 10-50 KGy; PaNP and NeNP exhibited well-defined glow curve when compared with MaNP samples. In addition, it was observed that the TL intensity decreases, with increase in gamma dose and the glow peak temperature is shifted towards the higher temperature with the increase in heating rate. The glow peak was segregated using glow curve deconvolution and thermal cleaning method. Kinetic parameters estimated using Chen's method, trap depth (E), and frequency factor (s) were found to be 0.699, 7.408, 0.4929, and 38.71, 11.008, and 10.71 for PaNP, NeNP, and MaNP respectively. The well-resolved glow curve, good linear behavior in the dose range of 10-50, KGy, and less fading were observed in PaNP as compared with MaNP and NeNP. Further, the antibacterial activity was checked against human pathogens such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. A visible zone of clearance was observed at 200 and 100 µg/mL by the PaNP and NeNP, indicating the death of colonies by the nanoparticles. Therefore, PaNP nanomaterial is a potential phosphor material for dosimetry and antibacterial application compared to NeNP and MaNP.

Synthesis, Molecular Docking Study, and Biological Evaluation of New 4-(2,5-Dimethyl-1H-pyrrol-1-yl)-N'-(2-(substituted)acetyl)benzohydrazides as Dual Enoyl ACP Reductase and DHFR Enzyme Inhibitors.

In this study, a new series of 4-(2,5-dimethyl-1H-pyrrol-1-yl)-N'-(2-(substituted)acetyl) benzohydrazides (5a-n) were prepared and new heterocycles underwent thorough characterization and evaluation for antibacterial activity; some of them underwent further testing for in vitro inhibition of enoyl ACP reductase and DHFR enzymes. The majority of the synthesized molecules exhibited appreciable action against DHFR and enoyl ACP reductase enzymes. Some of the synthesized compounds also showed strong antibacterial and antitubercular properties. In order to determine the potential mode of action of the synthesized compounds, a molecular docking investigation was conducted. The results revealed binding interactions with both the dihydrofolate reductase and enoyl ACP reductase active sites. These molecules represent excellent future therapeutic possibilities with potential uses in the biological and medical sciences due to the compounds' pronounced docking properties and biological activity.

Prevalence and Antibiogram Pattern of Klebsiella pneumoniae in a Tertiary Care Hospital in Makkah, Saudi Arabia: An 11-Year Experience.

Infectious disease is one of the greatest causes of morbidity and mortality worldwide, and with the emergence of antimicrobial resistance, the situation is worsening. In order to prevent this crisis, antimicrobial resistance needs to be monitored carefully to control the spread of multidrug-resistant bacteria. Therefore, in this study, we aimed to determine the prevalence of infection caused by Klebsiella pneumoniae and investigate the antimicrobial profile pattern of K. pneumoniae in the last eleven years. This retrospective study was conducted in a tertiary hospital in Makkah, Saudi Arabia. Data were collected from January 2011 to December 2021. From 2011 to 2021, a total of 61,027 bacterial isolates were collected from clinical samples, among which 14.7% (n = 9014) were K. pneumoniae. The antibiotic susceptibility pattern of K. pneumoniae revealed a significant increase in the resistance rate in most tested antibiotics during the study period. A marked jump in the resistance rate was seen in amoxicillin/clavulanate and piperacillin/tazobactam, from 33.6% and 13.6% in 2011 to 71.4% and 84.9% in 2021, respectively. Ceftazidime, cefotaxime, and cefepime resistance rates increased from 29.9%, 26.2%, and 53.9%, respectively, in 2011 to become 84.9%, 85.1%, and 85.8% in 2021. Moreover, a significant increase in the resistance rate was seen in both imipenem and amikacin, with an average resistance rate rise from 6.6% for imipenem and 11.9% for amikacin in 2011 to 59.9% and 62.2% in 2021, respectively. The present study showed that the prevalence and drug resistance of K. pneumoniae increased over the study period. Thus, preventing hospital-acquired infection and the reasonable use of antibiotics must be implemented to control and reduce antimicrobial resistance.

Energetic and frustration analysis of SARS-CoV-2 nucleocapsid protein mutations.

The ongoing COVID-19 spreads worldwide with the ability to evolve in diverse human populations. The nucleocapsid (N) protein is one of the mutational hotspots in the SARS-CoV-2 genome. The N protein is an abundant RNA-binding protein critical for viral genome packaging. It comprises two large domains including the N-terminal domain (NTD) and the C-terminal domain (CTD) linked by the centrally located linker region. Mutations in N protein have been reported to increase the severity of disease by modulating viral transmissibility, replication efficiency as well as virulence properties of the virus in different parts of the world. To study the effect of N protein missense mutations on protein stability, function, and pathogenicity, we analyzed 228 mutations from each domain of N protein. Further, we have studied the effect of mutations on local residual frustration changes in N protein. Out of 228 mutations, 11 mutations were predicted to be deleterious and destabilized. Among these mutations, R32C, R191C, and R203 M mutations fall into disordered regions and show significant change in frustration state. Overall, this work reveals that by altering the energetics and residual frustration, N protein mutations might affect the stability, function, and pathogenicity of the SARS-CoV-2.

Green Synthesis of Zn(OH)2/ZnO-Based Bionanocomposite using Pomegranate Peels and Its Application in the Degradation of Bacterial Biofilm.

The ability and potency of bacterial species to form biofilms, which show antibiotic resistance thereby avoiding antibiotic surfaces, is a major cause of prolonged infections. Various advanced approaches have been employed to prevent or damage bacterial biofilms, formed by a variety of bacterial strains, to help prevent the associated infectious disease. In this context, zinc-based nanostructures have been recognized as a potential antibiotic agent against a broad spectrum of bacterial communities. As a result, a sustainable and green synthesis method was adapted in the present study to synthesize a Zn(OH)2/ZnO-based bionanocomposite, in which aqueous extracts of waste pomegranate peels (Punica granatum) were employed as a natural bioreducing agent to prepare the bionanocomposite at room temperature. Furthermore, FT-IR, XRD, DLS, UV-Visible, PL spectroscopy, FE-SEM, and TEM were used to characterize the green route synthesized a Zn(OH)2/ZnO bionanocomposite. The average crystallite size was determined using the Scherrer relation to be 38 nm, and the DLS results indicated that the Zn(OH)2/ZnO bionanocomposite had a hydrodynamic size of 170 nm. On the other hand, optical properties investigated through UV-Vis and PL spectroscopy explored the energy bandgap between 2.80 and 4.46 eV, corresponding to the three absorption edges, and it covered the blue spectrum when the sample was excited at 370 nm. Furthermore, the impact of this green route synthesized a Zn(OH)2/ZnO bionanocomposite on the biofilm degradation efficiency of the pathogenic bacterial strain Bacillus subtilis PF_1 using the Congored method was investigated. The Congored assay clearly explored the biofilm degradation efficiency in the presence of a 50 mg/mL and 75 mg/mL concentration of the Zn(OH)2/ZnO bionanocomposite against the bacterial strain Bacillus subtilis PF_1 grown for 24 h. This study can be further applied to the preparation of bionanocomposites following a low-cost green synthesis approach, and thus prepared nanostructures can be exploited as advanced antimicrobial agents, which could be of great interest to prevent various infectious diseases.

Dose optimization of ß-lactams antibiotics in pediatrics and adults: A systematic review.

Background: ß-lactams remain the cornerstone of the empirical therapy to treat various bacterial infections. This systematic review aimed to analyze the data describing the dosing regimen of ß-lactams. Methods: Systematic scientific and grey literature was performed in accordance with Preferred Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The studies were retrieved and screened on the basis of pre-defined exclusion and inclusion criteria. The cohort studies, randomized controlled trials (RCT) and case reports that reported the dosing schedule of ß-lactams are included in this study. Results: A total of 52 studies met the inclusion criteria, of which 40 were cohort studies, 2 were case reports and 10 were RCTs. The majority of the studies (34/52) studied the pharmacokinetic (PK) parameters of a drug. A total of 20 studies proposed dosing schedule in pediatrics while 32 studies proposed dosing regimen among adults. Piperacillin (12/52) and Meropenem (11/52) were the most commonly used ß-lactams used in hospitalized patients. As per available evidence, continuous infusion is considered as the most appropriate mode of administration to optimize the safety and efficacy of the treatment and improve the clinical outcomes. Conclusion: Appropriate antibiotic therapy is challenging due to pathophysiological changes among different age groups. The optimization of pharmacokinetic/pharmacodynamic parameters is useful to support alternative dosing regimens such as an increase in dosing interval, continuous infusion, and increased bolus doses.

Thermophilic biohydrogen production strategy using agro industrial wastes: Current update, challenges, and sustainable solutions.

Continuously increasing wastes management issues and the high demand of fuels to fulfill the current societal requirements is not satisfactory. In addition, severe environmental pollution caused by generated wastes and the massive consumption of fossil fuels are the main causes of global warming. In this scenario, production of hydrogen from organic wastes is a potential and one of the most feasible alternatives to resolve these issues. However, sensitivity of H2 production at higher temperature and lack of potential substrates are the main issues which are strongly associated with such kinds of biofuels. Therefore, the present review is targeted towards the evaluation and enhancement of thermophilic biohydrogen production using organic, cellulosic wastes as promising bioresources. This review discusses about the current status, development in the area of thermophilic biohydrogen production wherein organic wastes as key substrate are being employed. The combinations of suitable organic and cellulose rich substrates, thermo-tolerant microbes, high enzymes stability may support to enhance the biohydrogen production, significantly. Further, various factors which may significantly contribute to enhance biohydrogen production have been discussed thoroughly in reference to the thermophilic biohydrogen production technology. Additionally, existing obstacles such as unfavorable thermophilic biohydrogen pathways, inefficiency of thermophilic microbiomes, genetic modifications, enzymes stability have been discussed in context to the possible limitations of thermophilic biohydrogen production strategy. Structural and functional microbiome analysis, fermentation pathway modifications via genetic engineering and the application of nanotechnology to enhance the thermophilic biohydrogen production have been discussed as the future prospective.

A Systematic Review on Clinical Safety and Efficacy of Vancomycin Loading Dose in Critically Ill Patients.

BACKGROUND: The clinical significance of utilizing a vancomycin loading dose in critically ill patients remains unclear. OBJECTIVE: The main aim of this systematic review is to evaluate the clinical safety and efficacy of the vancomycin loading dose in critically ill patients. METHODS: We performed a systematic review using PRISMA guidelines. PubMed, the Web of Science, MEDLINE, Scopus, Google Scholar, the Saudi Digital Library and other databases were searched. Studies that reported clinical outcomes among patients receiving the vancomycin LD were considered eligible. Data for this study were collected using PubMed, the Web of Science, MEDLINE, Scopus, Google Scholar and the Saudi Digital Library using the following terms: "vancomycin", "safety", "efficacy" and "loading dose" combined with the Boolean operator "AND" or "OR". RESULTS: A total of 17 articles, including 2 RCTs, 11 retrospective cohorts and 4 other studies, met the inclusion/exclusion criteria out of a total 1189 studies. Patients had different clinical characteristics representing a heterogenous group, including patients in critical condition, with renal impairment, sepsis, MRSA infection and hospitalized patients for hemodialysis or in the emergency department. CONCLUSIONS: The study shows that the target therapeutic level is achieved more easily among patients receiving a weight-based LD as compared to patients received the usual dose without an increased risk of new-onset adverse drug reactions.

Essential Oil Analysis and Antimicrobial Evaluation of Three Aromatic Plant Species Growing in Saudi Arabia.

Arabian flora is a rich source of bioactive compounds. In this study, we investigated three aromatic plant species with the aim of finding valuable sources of antimicrobial agents against common pathogenic microorganisms. We focused especially on microorganisms, which cause outbreaks of infectious disease during mass gatherings and pilgrimages season in Saudi Arabia. The essential oils of three aromatic plant species were hydrodistilled from flowering aerial parts of Lavandula pubescens Decne. and Pulicaria incisa subsp. candolleana E.Gamal-Eldin, and from leaves, stems, ripe and unripe fruits of Juniperus procera Hochst. Ex Endl. They were subsequently analyzed by gas chromatography-mass spectrometry (GC-MS). The main constituents of L. pubescens were found to be carvacrol (55.7%), methyl carvacrol (13.4%), and ß-bisabolene (9.1%). P. incisa subsp. Candolleana essential oil was rich in linalool (33.0%), chrysanthenone (10.3%), eugenol (8.9%), and cis-chrysanthenol (8.0%); the major components of J. procera essential oil were α-pinene (31.3-62.5%) and δ-3-carene (7.3-30.3%). These essential oils were tested against thirteen American Type Culture Collection (ATCC) strains of Gram-positive and Gram-negative bacteria using the agar diffusion assay. The only effective essential oil was that of L. pubescens and the most sensitive strains were Acinetobacter baumannii, Salmonella typhimurium, Shigella sonnei, Enterococcus faecalis and Staphylococcus epidermidis. Carvacrol, the major constituent of L. pubescens, was tested on these strains and was compared with vancomycin, amikacin, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays of L. pubescens essential oil and carvacrol revealed that Gram-negative strains were more susceptible than the Gram-positive ones.

Evaluation of Antimicrobial Stewardship Programs (ASPs) and their perceived level of success at Makkah region hospitals, Kingdom of Saudi Arabia.

Antimicrobial stewardship programs (ASPs) are collaborative efforts to optimize antimicrobial use in healthcare institutions through evidence-based quality improvement strategies. The general administration of pharmaceutical care in the Saudi ministry of health (MOH) is putting outstanding efforts in implementing antimicrobial stewardship in Saudi health care settings. Several surveys have been conducted globally and reported many types of antimicrobial stewardship strategies in health institutions and their effectiveness. This study aims to identify ASPs in Makkah region hospitals and their perceived level of success. We administered a regional survey to explore current progress and issues related to the implementation of ASPs in Makkah region hospitals at the pharmacy level (n = 25). Among responding hospitals, 19 (76%) hospitals, the most commonly reported ASP were as following: formulary restrictions (90%) for broad-spectrum antimicrobials and use of prospective feedback on antimicrobial prescribing (68%), use of clinical guidelines and pathways (100%), and use of automatic stop orders (68%) to limit inappropriate antimicrobial therapy. The study outcomes will also be of pivotal importance to devise policies and strategies for antimicrobial stewardship implementation in other non-MOH settings in the Makkah region. Based on our results, all reported institutions have at least one antimicrobial stewardship program in a process with a high success rate. A multidisciplinary ASP approach, active involvement of drug & therapeutic committee, formulary restrictions, and availability of education & training of pharmacists and physicians on ASP are the primary elements for perceived successful antimicrobial stewardship programs in the Makkah region hospitals.

Evaluation of a Multidisciplinary Antimicrobial Stewardship Program in a Saudi Critical Care Unit: A Quasi-Experimental Study.

Background: Antimicrobial stewardship programs (ASPs) are collaborative efforts to optimize antimicrobial use in healthcare institutions through evidence-based quality improvement strategies. With regard to critically ill patients, appropriate antimicrobial usage is of significance, and any delay in therapy increases their risk of mortality. Therefore, the implementation of structured multidisciplinary ASPs in critical care settings is of the utmost importance to promote the judicious use of antimicrobials. Methods: This quasi-experimental study evaluating a multidisciplinary ASP in a 20-bed critical care setting was conducted from January 1, 2016 to July 31, 2017. Outcomes were compared nine months before and after ASP implementation. The national antimicrobial stewardship toolkit by Ministry of health was reviewed and the hospital antibiotic prescribing policy was accordingly modified. The antimicrobial stewardship algorithm (Start Smart and Then Focus) and an ASP toolkit were distributed to all intensive care unit staff. Prospective audit and feedback, in addition to prescribing forms for common infectious diseases and education, were the primary antimicrobial strategies. Results: We found that the mean total monthly antimicrobial consumption measured as defined daily dose per 100 bed days was reduced by 25% (742.86 vs. 555.33; p = 0.110) compared to 7% in the control condition (tracer medications) (35.35 vs. 38.10; p = 0.735). Interestingly, there was a negative impact on cost in the post-intervention phase. Interestingly, the use of intravenous ceftriaxone measured as defined daily dose per 100 bed days was decreased by 82% (94.32 vs. 16.68; p = 0.008), whereas oral levofloxacin use was increased by 84% (26.75 vs. 172.29; p = 0.008) in the intensive care unit. Conclusion: Overall, involvement of higher administration in multidisciplinary ASP committees, daily audit and feedback by clinical pharmacists and physicians with infectious disease training, continuous educational activities about antimicrobial use and resistance, use of local antimicrobial prescribing guidelines based on up-to-date antibiogram, and support from the intensive care team can optimize antibiotic use in Saudi healthcare institutions.

In vitro inhibitory analysis of consensus siRNAs against NS3 gene of hepatitis C virus 1a genotype.

OBJECTIVE: To explore inhibitory effects of genome-specific, chemically synthesized siRNAs (small interference RNA) against NS3 gene of hepatitis C virus (HCV) 1a genotype in stable Huh-7 (human hepatoma) cells as well as against viral replication in serum-inoculated Huh-7 cells. METHODS: Stable Huh-7 cells persistently expressing NS3 gene were produced under antibiotic gentamycin (G418) selection. The cell clones resistant to 1000 µg antibiotic concentration (G418) were picked as stable cell clones. The NS3 gene expression in stable cell clone was confirmed by RT-PCR and Western blotting. siRNA cell cytotoxicity was determined by MTT cell proliferation assay. Stable cell lines were transfected with sequence specific siRNAs and their inhibitory effects were determined by RT-PCR, real-time PCR and Western blotting. The viral replication inhibition by siRNAs in serum inoculated Huh-7 cells was determined by real-time PCR. RESULTS: RT-PCR and Western blot analysis confirmed NS3 gene and protein expression in stable cell lines on day 10, 20 and 30 post transfection. MTT cell proliferation assay revealed that at most concentrated dose tested (50 nmol/L), siRNA had no cytotoxic effects on Huh-7 cells and cell proliferation remained unaffected. As demonstrated by the siRNA time-dependent inhibitory analysis, siRNA NS3-is44 showed maximum inhibition of NS3 gene in stable Huh-7 cell clones at 24 (80%, P = 0.013) and 48 h (75%, P = 0.002) post transfection. The impact of siRNAs on virus replication in serum inoculated Huh-7 cells also demonstrated significant decrease in viral copy number, where siRNA NS3-is44 exhibited 70% (P < 0.05) viral RNA reduction as compared to NS3-is33, which showed a 64% (P < 0.05) decrease in viral copy number. siRNA synergism (NS3-is33 + NS3-is44) decreased viral load by 84% (P < 0.05) as compared to individual inhibition by each siRNA (i.e., 64%-70% (P < 0.05)) in serum-inoculated cells. Synthetic siRNAs mixture (NS5B-is88 + NS3-is33) targeting different region of HCV genome (NS5B and NS3) also decreased HCV viral load by 85% (P < 0.05) as compared to siRNA inhibitory effects alone (70% and 64% respectively, P < 0.05). CONCLUSIONS: siRNAs directed against NS3 gene significantly decreased mRNA and protein expression in stable cell clones. Viral replication was also vividly decreased in serum infected Huh-7 cells. Stable Huh-7 cells expressing NS3 gene is helpful to develop anti-hepatitis C drug screening assays. siRNA therapeutic potential along with other anti-HCV agents can be considered against hepatitis C.

Risk factors associated with multi-drug-resistant Acinetobacter baumannii nosocomial infections at a tertiary care hospital in Makkah, Saudi Arabia - a matched case-control study.

Objective To determine risk factors for multi-drug-resistant Acinetobacter baumannii (MDR-AB) nosocomial infections in intensive care units in a tertiary care hospital, Makkah, Saudi Arabia. Methods We performed a hospital-based, matched case-control study in patients who were admitted to Al Noor Specialist Hospital between 1 January 2012 and 31 August 2012. The study included cases of A. baumannii nosocomial infection and controls without infection. Controls were matched to cases by age and ward of admission. Results The most frequent site of infection was the respiratory tract (77.3%). Susceptibility to antimicrobial MDR-AB was 92.0% for ceftazidime and ciprofloxacin, while it was 83.3% for imipenem, 83.0% for trimethoprim, 79.0% for amikacin, and 72.7% for gentamicin. Multiple logistic regression of risk factors showed that immunosuppression (OR = 2.9; 95% CI 1.5-5.6; p = 0.002), clinical outcome (OR = 0.4; 95% CI 0.3-0.9; p = 0.01), invasive procedures (OR = 7.9; 95% CI 1.8-34.2; p = 0.002), a central venous catheter (OR = 2.9; 95% CI 1.5-5.6; p = 0.000), and an endotracheal tube (OR = 3.4; 95% CI 1.6-7.3; p = 0.001) were associated with MDR-AB. Conclusions Acinetobacter nosocomial infections are associated with admission to the ICU (Intensive care unit) and exposure to invasive procedures.

CapA, an autotransporter protein of Campylobacter jejuni, mediates association with human epithelial cells and colonization of the chicken gut.

Two putative autotransporter proteins, CapA and CapB, were identified in silico from the genome sequence of Campylobacter jejuni NCTC11168. The genes encoding each protein contain homopolymeric tracts, suggestive of phase variation mediated by a slipped-strand mispairing mechanism; in each case the gene sequence contained frameshifts at these positions. The C-terminal two-thirds of the two genes, as well as a portion of the predicted signal peptides, were identical; the remaining N-terminal portions were gene specific. Both genes were cloned and expressed; recombinant polypeptides were purified and used to raise rabbit polyclonal monospecific antisera. Using immunoblotting, expression of the ca.116-kDa CapA protein was demonstrated for in vitro-grown cells of strain NCTC11168, for 4 out of 11 recent human fecal isolates, and for 2 out of 8 sequence-typed strains examined. Expression of CapB was not detected for any of the strains tested. Surface localization of CapA was demonstrated by subcellular fractionation and immunogold electron microscopy. Export of CapA was inhibited by globomycin, reinforcing the bioinformatic prediction that the protein is a lipoprotein. A capA insertion mutant had a significantly reduced capacity for association with and invasion of Caco-2 cells and failed to colonize and persist in chickens, indicating that CapA plays a role in host association and colonization by Campylobacter. In view of this demonstrated role, we propose that CapA stands for Campylobacter adhesion protein A.