Treatment Response Monitoring of Chronic Hepatitis B Patients using Transient Elastography and Aspartate Aminotransferase-to-Platelet Ratio Index (APRI)

Background: Hepatitis B is endemic in Indonesia and treatment response need to be monitored during and after antiviral therapy. Liver stiffness measurement and alanine aminotransferase-to-platelet ratio index (APRI) are noninvasive method to detect liver fibrosis available in Indonesia. However, little is known about their ability to evaluate treatment response in chronic hepatitis B (CHB) patients in Indonesia. This study aimed to investigate liver stiffness changes by transient elastography (TE) and APRI before and after one-year oral antiviral treatment in CHB patients and the correlation between TE and APRI. Methods: this study was retrospective cohort on CHB patients in CiptoMangunkusumo Hospital, Jakarta who uderwent treatment between January 2012 and December 2014. Patients received oral antiviral treatment with newer nucleoside analogues (entecavir or telbivudine) for at least one year. TE and APRI were obtained before and after treatment. TE and APRI reductions were analyzed statistically with Spearman’s test. Results: a total of 41 patients were enrolled in this study. Median liver stiffness value was significantly reduced from 10.8 to 5.9 kPa after oral antiviral treatment (p<0.001, Wilcoxon’s test). Median APRI was also significantly reduced from 1.13 to 0.43 after treatment (p<0.001, Wilcoxon’s test). The correlation between liver stiffness and APRI before treatment was weak (r=0.40), but it was strong after treatment (r=0.73). Conclusion: the liver stiffness measured with transient elastography and APRI significantly decreased after one year of antiviral treatment in chronic HBV patients. There was a significant correlation between TE and APRI after one year of treatment

Shigella spp. surveillance in Indonesia: the emergence or reemergence of S. dysenteriae.

From June 1998 through November 1999, Shigella spp. were isolated in 5% of samples from 3,848 children and adults with severe diarrheal illness in hospitals throughout Indonesia. S. dysenteriae has reemerged in Bali, Kalimantan, and Batam and was detected in Jakarta after a hiatus of 15 years

20 Years of Progress in Typhoid Research

In 1981, the reported number of cases of typhoid fever in Indonesia was 19,596, increasing to 26,606 m 1986, most of the increase was due to improved detection and recognition of the pathogen. A more realistic estimate of incidence for this underreported and underdiagnosed disease would be from 540,000 to 1,210,000 cases per year. This was based on results of a household survey done by Budiarso R. et al. in 1980 and 1986, and on result of a community surveillance done by Ruwido and Simanjuntak et al. from 1983-1988. These studies were done in Plaju, South Sumatera, representing an urban area and Paseh, West Java, representing a semi-rural area. The results showed that the incidence rate of typhoid fever in the semi rural area was 358/100,000 population/year, and between 760-810/100,000 population/year in the urban area. These studies also indicated that the high risk group in the population was school age children between ages of 3-19 years. From other observations, it is also noted that the case fatality in urbanized and growing areas of Indonesia, may be higher than it is reported in other areas of the worl

20 Years of Progress in Diarrheal Disease Research

When NAMRU started its collaboration work with the National Institute of Health, Research and Development (NIHRD), it became apparent that diarrheal disease was one of the most important causes of morbidity and mortality in Indonesia, especially in children. Many of the most important etiologic agents of diarrhea were not known and the percentage of diarrheas with an identifiable etiologic agent was very low. Since these early times NAMRU and NIHRD have worked together in all aspects of diarrheal disease research. Increased capabilities for the identification of bac­tériologie, parasitic and viral enteropathogens, new vaccines, and better treatment via oral rehydration solutions are some of the results of this collaboration

A finite difference method for pricing European and American options under a geometric Lévy process

In this paper we develop a numerical approach to a fractional-order differential Linear Complementarity Problem (LCP) arising in pricing European and American options under a geometric Lévy process. The LCP is first approximated by a nonlinear penalty fractional Black-Scholes (fBS) equation. We then propose a finite difference scheme for the penalty fBS equation. We show that both the continuous and the discretized fBS equations are uniquely solvable and establish the convergence of the numerical solution to the viscosity solution of the penalty fBS equation by proving the consistency, stability and monotonicity of the numerical scheme. We also show that the discretization has the 2nd-order truncation error in both the spatial and time mesh sizes. Numerical results are presented to demonstrate the accuracy and usefulness of the numerical method for pricing both European and American options under the geometric Lévy process

An interior penalty method for a finite-dimensional linear complementarity problem in financial engineering

In this work we study an interior penalty method for a finite-dimensional large-scale linear complementarity problem (LCP) arising often from the discretization of stochastic optimal problems in financial engineering. In this approach, we approximate the LCP by a nonlinear algebraic equation containing a penalty term linked to the logarithmic barrier function for constrained optimization problems. We show that the penalty equation has a solution and establish a convergence theory for the approximate solutions. A smooth Newton method is proposed for solving the penalty equation and properties of the Jacobian matrix in the Newton method have been investigated. Numerical experimental results using three non-trivial test examples are presented to demonstrate the rates of convergence, efficiency and usefulness of the method for solving practical problems

Consensus recommendations of three-dimensional visualization for diagnosis and management of liver diseases

Three-dimensional (3D) visualization involves feature extraction and 3D reconstruction of CT images using a computer processing technology. It is a tool for displaying, describing, and interpreting 3D anatomy and morphological features of organs, thus providing intuitive, stereoscopic, and accurate methods for clinical decision-making. It has played an increasingly significant role in the diagnosis and management of liver diseases. Over the last decade, it has been proven safe and effective to use 3D simulation software for pre-hepatectomy assessment, virtual hepatectomy, and measurement of liver volumes in blood flow areas of the portal vein; meanwhile, the use of 3D models in combination with hydrodynamic analysis has become a novel non-invasive method for diagnosis and detection of portal hypertension. We herein describe the progress of research on 3D visualization, its workflow, current situation, challenges, opportunities, and its capacity to improve clinical decision-making, emphasizing its utility for patients with liver diseases. Current advances in modern imaging technologies have promised a further increase in diagnostic efficacy of liver diseases. For example, complex internal anatomy of the liver and detailed morphological features of liver lesions can be reflected from CT-based 3D models. A meta-analysis reported that the application of 3D visualization technology in the diagnosis and management of primary hepatocellular carcinoma has significant or extremely significant differences over the control group in terms of intraoperative blood loss, postoperative complications, recovery of postoperative liver function, operation time, hospitalization time, and tumor recurrence on short-term follow-up. However, the acquisition of high-quality CT images and the use of these images for 3D visualization processing lack a unified standard, quality control system, and homogeneity, which might hinder the evaluation of application efficacy in different clinical centers, causing enormous inconvenience to clinical practice and scientific research. Therefore, rigorous operating guidelines and quality control systems need to be established for 3D visualization of liver to develop it to become a mature technology. Herein, we provide recommendations for the research on diagnosis and management of 3D visualization in liver diseases to meet this urgent need in this research field

A penalty approach to a discretized double obstacle problem with derivative constraints

This work presents a penalty approach to a nonlinear optimization problem with linear box constraints arising from the discretization of an infinite-dimensional differential obstacle problem with bound constraints on derivatives. In this approach, we first propose a penalty equation approximating the mixed nonlinear complementarity problem representing the Karush-Kuhn-Tucker conditions of the optimization problem. We then show that the solution to the penalty equation converges to that of the complementarity problem with an exponential convergence rate depending on the parameters used in the equation. Numerical experiments, carried out on a non-trivial test problem to verify the theoretical finding, show that the computed rates of convergence match the theoretical ones well

Pandemic Boredom: Little Evidence That Lockdown-Related Boredom Affects Risky Public Health Behaviors Across 116 Countries

Some public officials have expressed concern that policies mandating collective public health behaviors (e.g., national/regional "lockdown ") may result in behavioral fatigue that ultimately renders such policies ineffective. Boredom, specifically, has been singled out as one potential risk factor for noncompliance. We examined whether there was empirical evidence to support this concern during the COVID-19 pandemic in a large cross-national sample of 63,336 community respondents from 116 countries. Although boredom was higher in countries with more COVID-19 cases and in countries that instituted more stringent lockdowns, such boredom did not predict longitudinal within-person decreases in social distancing behavior (or vice versa; n = 8,031) in early spring and summer of 2020. Overall, we found little evidence that changes in boredom predict individual public health behaviors (handwashing, staying home, self-quarantining, and avoiding crowds) over time, or that such behaviors had any reliable longitudinal effects on boredom itself. In summary, contrary to concerns, we found little evidence that boredom posed a public health risk during lockdown and quarantine