Gadjah Mada University

About: Gadjah Mada University is a education organization based out in Yogyakarta, Indonesia. It is known for research contribution in the topics: Population & Adsorption. The organization has 17307 authors who have published 21389 publications receiving 116561 citations. The organization is also known as: University of Gajah Mada & Universitas Gadjah Mada.

Adhesion failure behavior of sputtered calcium phosphate thin film coatings evaluated using microscratch testing

Abstract: It is generally accepted that calcium phosphate (CaP) is one of the most important biomaterials in implant coating applications mainly because of its excellent bioactivity. However, its relatively poor mechanical properties limits its application. This entails that a better understanding of the mechanical properties of a CaP coating is a must especially its behavior and the mechanisms involved when subjected to stresses which eventually lead to failure. The mechanical properties of the coating may be evaluated in terms of its adhesion strength. In this study, a radio frequency-magnetron (RF-MS) sputtering technique was used to deposit CaP thin films on 316L stainless steel (SS). The coatings were subjected to series of microscratch tests, taking careful note of its behavior as the load is applied. The adhesion behavior of the coatings showed varying responses. It was revealed that several coating process-related factors such as thickness, post-heat treatment and deposition parameters, to name a few, affect its scratching behavior. Scratch testing-related factors (i.e. loading rate, scratch speed, scratch load, etc.) were also shown to influence the mechanisms involved in the coating adhesion failure. Evaluation of the load-displacement graph combined with optical inspection of the scratch confirmed that several modes of failure occurred during the scratching process. These include trackside cracking, tensile cracking, radial cracking, buckling, delamination and combinations of one or more modes.

Health-Seeking Behavior of People in Indonesia: A Narrative Review.

Abstract: This review aims to locate existing studies on health-seeking behavior of people in Indonesia, identify gaps, and highlight important findings. Articles were retrieved from Medline, Scopus, Web of Science, Academic Search Complete (via Ebsco), and ProQuest with a number of key words and various combinations. Articles from Indonesian journals were also searched for with Google Scholar. A total of 56 articles from peer-reviewed journal databases and 19 articles from Indonesian journals were reviewed. Quantitative designs were applied more frequently than qualitative, and mixed methods designs were used in some studies. The majority gathered retrospective information about people's behaviors. Communicable diseases and maternity care were the most frequently studied conditions, in contrast to noncommunicable diseases. In terms of geographical distribution, most research was conducted on Java island, with very few in outside Java. Important findings are a model of Indonesian care-seeking pathways, an understanding of determinants of people's care choices, and the role of sociocultural beliefs. The findings from this narrative review provide insight to what and how Indonesians make decisions to manage their illness and why. This makes an important contribution to understanding the problem of underutilization of medical services despite the government's extensive efforts to improve accessibility.

Journeys to tuberculosis treatment: a qualitative study of patients, families and communities in Jogjakarta, Indonesia

Abstract: Many tuberculosis (TB) patients in Indonesia are diagnosed late We seek to document patient journeys toward TB diagnosis and treatment and factors that influence health care seeking behavior TB patients in Jogjakarta municipality (urban) and Kulon Progo district (rural) were recruited from health care facilities participating in the DOTS strategy and health care facilities not participating in the DOTS strategy, using purposive sampling methods Data were collected through in-depth interviews with TB patients and members of their family and through Focus Group Discussions (FGD) with community members In total, 67 TB patients and 22 family members were interviewed and 6 FGDs were performed According to their care seeking behavior patients were categorized into National TB program's (NTP) dream cases (18%), 'slow-but-sure patients' (34%), 'shopaholics' (45%), and the NTP's nightmare case (3%) Care seeking behavior patterns did not seem to be influenced by gender, place of residence and educational level Factors that influenced care seeking behavior include income and advice from household members or friends Family members based their recommendation on previous experience and affordability FGD results suggest that the majority of people in the urban area preferred the hospital or chest clinic for diagnosis and treatment of TB whereas in the rural area private practitioners were preferred Knowledge about TB treatment being free of charge was better in the urban area Many community members from the rural area doubted whether TB treatment would be available free of charge Most TB patients took over a month to reach a DOTS facility after symptoms appeared and had consulted a number of providers Their income and advice from household members and friends were factors that influenced their care seeking behavior most

Dried-Blood Sampling for Epstein-Barr Virus Immunoglobulin G (IgG) and IgA Serology in Nasopharyngeal Carcinoma Screening

Abstract: Dried-blood (DB) samples on filter paper are considered clinical specimens for diagnostic use because of the ease of collection, storage, and transport. We recently developed a synthetic-peptide-based immunoglobulin A (IgA) (EBNA1 plus viral capsid antigen [VCA]-p18) enzyme-linked immunosorbent assay (ELISA) for nasopharyngeal carcinoma (NPC) screening. Here, we evaluate the use of two filter papers for DB sampling, i.e., Schleicher & Schuell (SS the DB samples were either taken directly from a finger prick or spotted from a Vacutainer blood collector. The elution of DB samples on filter paper was optimized and tested for IgG and IgA reactivity by ELISA (EBNA1 plus VCA-p18) and compared to simultaneously collected plasma samples. The results showed that both types of filter paper can be used for sample collection in NPC diagnosis by using either finger prick or blood spot sampling. Both DB sampling methods produced comparable ELISA (EBNA1 plus VCA-p18) results for IgG and IgA reactivity in 1:100-diluted plasma samples. DB samples of whole blood or finger prick blood show correlation coefficients (r2) of 0.825 to 0.954 for IgA on S&S no. 903 filter paper, 0.9133 to 0.946 for IgA on Whatman no. 3 filter paper, 0.807 to 0.886 for IgG on S&S no. 903 filter paper, and 0.819 to 0.934 for IgG on Whatman no. 3 filter paper. Using plasma IgA as a reference, DB sampling showed sensitivities and specificities of 75.0 to 96.0% and 93.5 to 100%, respectively. DB samples could be stored at 37°C for 1 to 4 weeks on S&S no. 903 filter paper and 1 to 6 weeks on Whatman no. 3 filter paper without a significant loss of reactivity, with provision of transport options for tropical conditions. IgA proved to be more stable than IgG. Whatman no. 3 filter paper is a more economical yet diagnostically comparable alternative to S&S no. 903 filter paper. Finger prick DB sampling is proposed for NPC diagnosis, particularly for remote hospitals and field screening studies.

Bioceramic hydroxyapatite-based scaffold with a porous structure using honeycomb as a natural polymeric Porogen for bone tissue engineering.

Abstract: The application of bioceramic hydroxyapatite (HA) derived from materials high in calcium to tissue engineering has been of concern, namely scaffold. Scaffold pores allow for cell mobility metabolic processes, and delivery of oxygen and nutrients by blood vessel. Thus, pore architecture affects cell seeding efficiency, cell viability, migration, morphology, cell proliferation, cell differentiation, angiogenesis, mechanical strength of scaffolds, and, eventually, bone formation. Therefore, to improve the efficacy of bone regeneration, several important parameters of the pore architecture of scaffolds must be carefully controlled, including pore size, geometry, orientation, uniformity, interconnectivity, and porosity, which are interrelated and whose coordination affects the effectiveness of bone tissue engineering. The honeycomb (HCB) as natural polymeric porogen is used to pore forming agent of scaffolds. It is unique for fully interconnected and oriented pores of uniform size and high mechanical strength in the direction of the pores. The aim of this study was therefore to evaluate the effect of HCB concentration on macropore structure of the scaffolds. Bioceramic hydroxyapatite (HA) was synthesized from abalone mussel shells (Halioitis asinina) using a precipitation method, and HA-based scaffolds were fabricated with honeycomb (HCB) as the porogen agent. Pore structure engineering was successfully carried out using HCB at concentrations of 10, 20, and 30 wt%. The Energy Dispersive X-Ray Spectroscopy (EDS) analysis revealed that the Ca/P molar ratio of HA was 1.67 (the stoichiometric ratio of HA). The Fourier Transform Infrared Spectroscopy (FTIR) spectra results for porous HA-based scaffolds and synthesized HA showed that no chemical decomposition occurred in the HA-based scaffold fabrication process. The porosity of the scaffold tended to increase when higher concentrations of HCB were added. XRD data show that the HCB was completely degraded from the scaffold material. The cell metabolic activity and morphology of the HA + HCB 30 wt% scaffold enable it to facilitate the attachment of MC3T3E1 cells on its surface. HCB 30 wt% is the best concentration to fabricate the scaffold corresponding to the criteria for pores structure, crystallographic properties, chemical decomposition process and cell viability for bone tissue engineering.