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The relatedness between viral variants sampled at different locations through time can provide information pertinent to public health that cannot readily be obtained through standard surveillance methods. Here, we use virus genetic data to identify the transmission dynamics that drive the hepatitis C virus subtypes 4a (HCV4a) and 4d (HCV4d) epidemics in Saudi Arabia. We use a comprehensive dataset of newly generated and publicly available sequence data to infer the HCV4a and HCV4d evolutionary histories in a Bayesian statistical framework. We also introduce a novel analytical method for an objective assessment of the migration intensity between locations. We find that international host mobility patterns dominate over within country spread in shaping the Saudi Arabia HCV4a epidemic, while this may be different for the HCV4d epidemic. This indicates that the subtypes 4a and 4d burden can be most effectively reduced by combining the prioritized screening and treatment of Egyptian immigrants with domestic prevention campaigns. Our results highlight that the joint investigation of evolutionary and epidemiological processes can provide valuable public health information, even in the absence of extensive metadata information.

This study aims to improve the low shear strength of an exterior beam-column joint (BCJ) by using a different reinforcement pattern or ultra-high performance fiber-reinforced concrete (UHPFRC) in the beam-column joint. The main studied parameters were the transverse reinforcement ratio, anchorage of the longitudinal beam reinforcement, beam-column depth ratio, and utilizing UHPFRC. Five specimens with a one-third scale were experimentally tested under one-direction cyclic loading. All the samples were compared to the control sample in terms of crack pattern, mode of failure, hysteresis and envelope behavior, ductility factor, energy dissipation, normalized shear strength, percentage of beam flexural capacity, and stiffness degradation. Compared to the control specimen, the joint shear strength increases by 13%, 25%, 9%, and 38% for specimens that were made better by increasing the transverse reinforcement ratio, increasing the beam anchorage bar length in the joint, lowering the beam-column depth ratio to 0.80, and using UHPFRC instead of normal concrete in the beam-column joint. The UHPFRC in BCJ can be used instead of increasing the anchorage of the beam bars or the transverse reinforcement within the joint to get the same or better shear strength performance. [ABSTRACT FROM AUTHOR]

There are various benefits to ultra-high-performance fiberreinforced concrete (UHPFRC). However, using a lot of cement in this type of concrete has a severe disadvantage since it causes pollution and several environmental concerns. Therefore, another type of concrete that achieves the same superior properties as UHPFRC while using less cement in the mixture should be considered. This research examined replacing cement with fly ash to produce environmentally friendly concrete called Green-UHPFRC. The impact of utilizing G-UHPFRC on the flexural behaviour of thirteen beams was investigated experimentally and numerically under repeated loads. The major parameters of the study were fly ash replacement ratios of 15%, 30%, and 45% and adding steel fiber to mixes with ratios of 1, 2, 3, and 4%. The tested beams were compared to the control beam in their backbone and hysteresis curves, failure load, crack propagation and failure modes, energy dissipation, stiffness degradation, and ductility index. From the results obtained, environmentally friendly concrete (G-UHPFRC) can be produced by replacing cement with fly ash up to 45% and adding 2% steel fiber without affecting the bending performance of beams made of G-UHPFRC compared to those made of UHPFRC. [ABSTRACT FROM AUTHOR]

This research studies and assesses the possibility of employing ultra-high performance fiber reinforced concrete (UHPFRC) in exterior beam-column joints (BCJs). Eight specimens with various concrete material characteristics and steel reinforcing details are cast and examined under repeated loads. Normal concrete with seismic reinforcing details is used as a control specimen. For certain specimens, UHPC, UHPFRC with 1% steel fiber, and UHPFRC with 2% steel fiber are poured into all BCJs, and others are poured into the critical zone only. The consequences of removing stirrups from the joint were studied. All specimens' crack patterns, hysteresis and envelope curves, ductility factor, stiffness degradation, and energy dissipation are assessed and corresponded to the control sample. The results demonstrate that UHPFRC strengthened the joint, prevented crack development and extension and the shear failure in the joint, and formed the plastic hinge in the beams. UHPFRC outperforms normal concrete with seismic reinforcing details and UHPC without steel fiber in bearing capacity, ductility, stiffness, and energy dissipation. UHPFRC with 1% steel fiber enhanced joint behavior, while UHPFRC with 2% steel fiber was better. Casting the whole sample with UHPFRC achieved very little improvement. The presence of stirrups in the UHPFRC beam-column joint has little effect on its properties. It is more economical to cast UHPFRC in the joint zone only and reduce or eliminate these stirrups in the case of UHPFRC. [ABSTRACT FROM AUTHOR]

Due to the depletion of natural aggregates and raw materials for contemporary construction, the construction and demolition waste existing in old concrete structures is an imperative problem. Cutting down on exploiting natural aggregates and reusing construction and demolition waste in the concrete industry are solutions to this problem. This paper investigated the replacement of natural coarse aggregate (NCA) with recycled concrete aggregates (RCA) with different ratios (0%, 50%, 75%, and 100%) in producing self-compacting concrete (SCC). Different components of supplementary cementitious materials (SCMs), such as nano-silica (NS), fly ash (FA), and metakaolin (MK), as well as PVA fibers, were incorporated into the SCC mixtures. The fresh properties (slump flow, V-funnel, and L-box test) and hardened properties (compressive strength, splitting tensile strength, and flexural strength), as well as the flexural behavior of SCC beams (load-carrying capacity, crack pattern, mid-span deflection, and flexural stiffness), were studied for all SCC mixes. The results of fresh and hardened concrete confirmed that it is possible to produce SCC with a 100% replacement of RCA with minimal effects on the concrete properties. The mixture of SCC with 100% RCA replacement, 20% MK, and 22% FA was the optimum mixture with acceptable fresh properties that complied with the EFNARC specifications. For 100% RCA replacement, the compressive strength was reduced by 8.20%, and the ultimate load and flexural stiffness increased by 3.20 and 16.25%, respectively, compared with the control mixture. [ABSTRACT FROM AUTHOR]

Background and Objectives: There are few reports on hepatitis C virus genotype 4 (HCV-4) recurrences after orthotopic liver transplantation (OLT). Therefore, we undertook a study to determine the epidemiological, clinical and virological characteristics of patients with biopsy-proven recurrent HCV infection and analyzed the factors that influence recurrent disease severity. We also compared disease recurrence and outcomes between HCV-4 and other genotypes. Patients and Methods: All patients who underwent OLT (locally or abroad) for HCV related hepatic cir-- rhosis from 1991 to 2006 and had recurrent HCV infection were identified. Clinical, laboratory and pathological data before and after OLT were collected and analyzed. Results: Of 116 patients who underwent OLT for hepatitis C, 46 (39.7%) patients satisfied the criteria of recur--rent hepatitis C. Twenty-nine (63%) patients were infected with HCV genotype 4. Mean (SD) for age was 54.9 (10.9) years. Nineteen of the HCV genotype 4 patients (65.5%) were males, 21 (72.4%) received deceased donor grafts, and 7 (24.1%) developed> 1 acute rejection episodes. Pathologically, 7 (24.1%) and 4 (13.8%) patients had inflammation grade 3-4 and fibrosis stage 3-4, respectively. Follow-up biopsy in 9 (31%) HCV genotype 4 patients showed stable, worse and improved fibrosis stage in 5, 2 and 2 patients, respectively. Of the 7 patients in the recurrent HCV group who died, 6 were infected with genotype 4 and 4 of them died of HCV-related disease. Conclusion: This analysis suggests that HCV recurrence following OLT in HCV-4 patients is not significantly different from its recurrence for other genotypes.

Hepatitis C is a systemic disease that has many extrahepatic manifestations in addition to hepatic inflammation and fibrosis, some of which may result in a poor health-related quality of life (HRQOL). Fatigue is perhaps the most frequent and disabling extrahepatic symptom of hepatitis C virus (HCV), reported in almost one-half of all chronically infected individuals. Many other factors are associated with a poor quality of life in patients with HCV, including a number of physical and psychological factors. The objective of this article is to review the association between HCV and impaired HRQOL due to fatigue and psychological disturbances.

Background: Saudi Arabia is a leading country in the Middle East in the field of deceased-donor liver transplantation (DDLT) and living-donor liver transplantation (LDLT). We present out experience with DDLT and LDLT at King Faisal Specialist Hospital and Research Center (KFSHRC) for the period from April 2001 to January 2007. Patients and Methods: We performed 122 LT procedures (77 DDLTs and 45 LDLTs) in 118 patients (4 re-transplants) during this period of time. Results: The number of adult and pediatric procedures was 107 and 11, respectively. The overall male/female ratio was 66/52 and the median age of patients was 43 years (range, 2-63 years). In the DDLT group, the me--dian operating time was 8 hours (range, 4-19), the median blood transfusion was 6 units (range, 0-40), and the median hospital stay was 13 days (range, 6-183). In the DDLT group, after a mean follow-up period of 760 days (range, 2-2085), the overall patient and graft survival rate was 86%. In the LDLT group, the median operating time was 11 hours (range, 7-17), the median blood transfusion was 4 units (range, 0-65), and the median hospital stay was 15 days (range, 7-127). In the LDLT group, and after a mean follow-up period of 685 days (range, 26-1540), the overall patient and graft survival rates were 90% and 80%, respectively with no significant difference in patient and graft survivals between groups. Biliary complications were significantly higher in LDLT compared to DDLT (P< 0.05). Vascular complications were also significantly higher in LDLT compared DDLT (P< 0.05). Conclusions: Both DDLT and LDLT are being successfully performed at KFSHRC with early experience indicating a higher rate of biliary and vascular complications in the LDLT group.

Background: Hepatocellular carcinoma (HCC) is the second commonest cancer affecting males and the eighth most common one affecting females in Saudi Arabia. Transarterial chemoembolization (TACE) is currently considered the first line therapy for multifocal HCC in selected patients. Objective: To evaluate HCC response to TACE based on triphasic computerized tomography (CT) of the liver obtained 6 weeks after the procedure. Materials and Methods: A retrospective chart review of 15 patients who underwent TACE in King Khalid University Hospital for unresectable HCC. Patients were staged according to the Child-Pugh, Okuda, and CLIP scoring systems. The first triphasic CT of the liver after TACE was evaluated for Lipiodol uptake and interval change in tumor burden. Results: The mean age was 63 years (40-82), 10 were males (66.7%), and five were females. About 11 patients had cirrhosis (73.3%). Eight patients (53.3%) were Child-Pugh class A while seven (46.7%) were Child-Pugh class B. One patient died and two were lost to follow up. Four patients had a complete response to TACE (26.7%), two had a partial response (13.3%), five showed no change (33.3%) and none showed progression of disease. Tumoral Lipiodol uptake in five patients was> 75% (33.3%), in two 75-50% (13.3%) while in four patients it was < 50% (26.7%). Conclusion: Our results show that TACE is an effective method of reducing the tumor burden in selected patients with unresectable HCC.

Background: We tested the clinical utility of the platelet count, the aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio, and the AST to platelet ratio index (APRI) score in predicting the presence or absence of advanced fibrosis and cirrhosis in patients with chronic hepatitis C in Saudi Arabia. Methods: Liver biopsy procedures performed on chronic hepatitis C patients in our gastroenterology unit at King Khalid University Hospital were traced from records between the years 1998 to 2003. The hospital com--puter database was then accessed and detailed laboratory parameters obtained. By plotting receiver operating characteristic curves (ROC), three selected models (platelet count, AST/ALT ratio, and the APRI score) were compared in terms of the best variable to predict significant fibrosis. Results: Two hundred and forty-six patients with hepatitis C were included in this analysis. Overall, 26% of patients had advanced fibrosis. When comparing the three above-mentioned prediction models, the APRI score was the one associated with the highest area under the curve (AUC) = 0.812 (95% CI, 0.756-0.868) on the ROC curves, compared to the platelet count and AST/ALT ratio, which yielded an AUC of 0.783 (0.711-0.855) and 0.716 (0.642-0.789), respectively. Conclusion: The APRI score seemed to be the best predictive variable for the presence or absence of advanced fibrosis in Saudi hepatitis C patients

Objective: To identify laboratory predictors of advanced fibrosis in Saudi Arabian patients with hepatitis B and C. Materials and Methods: Histopathology reports were obtained on all patients who had liver biopsy in the last 5 years, and relevant laboratory data were collected. Results: A total of 328 patients (246 with hepatitis C and 82 with hepatitis B) were included. With logistic regression analysis, four factors were found to be the best predictors of fibrosis, namely, platelet count, ALT, AST and GGT levels. An equation for calculating the risk of advanced fibrosis was developed. The model had a sensitivity of 62%, a specificity of 92.4% and an overall accuracy of 84%. Conclusion: Platelet count, ALT, AST and GGT levels were found to be the best predictors of advanced fibrosis on liver biopsy in Saudi patients with chronic hepatitis B and C. An equation was developed that helps in calculating this risk.

Hepatic encephalopathy (HE) is a disturbance of the central nervous system (CNS) function secondary to porto-systemic shunting. It usually occurs in the setting of advanced liver cirrhosis or acute fulminant hepatic failure. An extensive Medline search was undertaken and all relevant papers found were critically examined. Special emphasis was paid to clinical trials and meta-analyses. All guidelines and conference proceedings related to hepatic encephalopathy were also examined. HE presents with a spectrum of neuropsychiatric manifestations that may be quite subtle (minimal HE) or overt, ranging from disturbance of the sleep pattern to deep hepatic coma. Most patients with HE may be diagnosed on clinical grounds only after excluding other causes of neurological disease, but a wide variety of neuropsychological, neurophysiological, and neuroradiological tests may be utilized. The first step in the management of patients with HE should be supportive care. Following that, a significant effort must be exerted to find and correct possible exacerbating factors which may include: renal impairment, infection, constipation, drugs, gastrointestinal bleeding and other factors. Medications used to treat patients with encephalopathy aim to reduce toxin production, increase toxin elimination, and protect the brain from the harmful effects of these toxins. A critical analysis of the evidence concerning most of the available management modalities is presented. Ultimately, all patients with HE must be considered for liver transplantation. It is concluded that early recognition, positive diagnosis, and a multi-target management plan constitutes appropriate management of patients with HE.

Background: Autoimmune hepatitis (AIH) is a relapsing inflammatory disease of the liver of unknown cause. Little is known about AIH in Saudi Arabia. Objectives: Our aim is to [1] identify the special clinical or histological features in our patients[2], describe the initial response to immunosuppressive therapy and long term relapse[3], identify clinical and laboratory predictors of response to therapy, and [4] examine the utility of laboratory markers (platelet count, AST/ALT ratio, and the AST to platelet ratio index (APRI score) in predicting the presence of advanced fibrosis. Methods: Patients were identified using a computer database. Patients responding to initial therapy were compared with patients who did not respond in terms of laboratory and histology parameters. The utility of three fibrosis markers/models were then examined. Results: Thirty-nine patients with AIH were included in this analysis. The mean age was 45.4; 65% of patients were females. Mean ALT at presentation was 268 U/L and AST was 277 U/ L. GGT level was found to be the only statistically significant laboratory or histopathological parameter difference between responders and non-responders. Platelet count and AST/ALT ratio were found to be the best predictors of advanced fibrosis. Conclusion: In Saudi patients with AIH, we found that the GGT level at presentation may serve as a useful predictor for response to therapy. Platelet count and AST/ALT ratio may be used to predict advanced fibrosis.

Background: Screening endoscopy for varices may be deferred when the calculated EVendo score is ≤3.90. This novel score has not been validated in an external cohort. This study aimed to assess the performance of the EVendo score and compare it with the Baveno VI criteria. Methods: We identified and calculated this score in all cirrhotic patients who underwent screening endoscopy for the first time with laboratory tests and liver stiffness measurements within 6 months of the endoscopy date. Results: In total, 103 patients were included. An EVendo score of ≤3.90 identified patients with no gastroesophageal varices (GEV) and varices needing treatment (VNT) with sensitivities of 82% and 83% and specificities of 57% and 34%, respectively. The negative predictive value for VNT was 94%. A comparison with the Baveno VI criteria in Child–Turcotte–Pugh-A patients showed spared endoscopy and missed VNT rates with EVendo score cutoffs of ≤3.9 and ≤4.5 and the Baveno VI criteria of 25%, 33%, and 16.6% and 1.7%, 1.7%, and 0%, respectively. Conclusions: EVendo score is reliable in clinical practice for predicting GEV and VNT. The number of spared endoscopies was higher than that with the Baveno VI criteria; however, there were more missed VNT cases. [ABSTRACT FROM AUTHOR]