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0000-0002-2911-9705
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Publisher: Elsevier BV
Date: 05-2021
Publisher: Hindawi Limited
Date: 27-03-2021
DOI: 10.1155/2021/6623400
Abstract: Chikungunya (CHIK) is a reemerging arboviral disease caused by chikungunya virus (CHIKV) infection. The disease is clinically hallmarked by prolonged debilitating joint pain. Currently, there is no specific antiviral medication nor commercial vaccine available for treatment of the disease, which makes the discovery or development of specific anti-CHIKV compounds a priority. Ginger (Zingiber officinale Roscoe) is widely known for its various health benefits. The compound [6]-gingerol is the main active ingredient found in ginger. This study sought to determine the potential of [6]-gingerol antiviral activity against CHIKV infection using in vitro human hepatocyte HepG2 cells. The antiviral activity mechanism was investigated using direct virucidal and four indirect (pre-, post-, full-, and prevention) treatment assays. [6]-Gingerol showed weak virucidal activity but significant indirect antiviral activity against CHIKV through post- and full treatment with I C 50 of 0.038 mM and 0.031 mM, respectively, without showing cell cytotoxicity. The results indicated that [6]-gingerol inhibits CHIKV infection through suppression of viral replication. Together, this study confirms the potential use of [6]-gingerol for CHIK antiviral compound.
Publisher: Frontiers Media SA
Date: 20-11-2020
Abstract: The people of Indonesia have been afflicted by dengue, a mosquito-borne viral disease, for over 5 decades. The country is the world's largest archipelago with erse geographic, climatic, and demographic conditions that may impact the dynamics of disease transmissions. A dengue epidemiology study was launched by us to compare and understand the dynamics of dengue and other arboviral diseases in three cities representing western, central, and eastern Indonesia, namely, Batam, Banjarmasin, and Ambon, respectively. A total of 732 febrile patients were recruited with dengue-like illness during September 2017–2019 and an analysis of their demographic, clinical, and virological features was performed. The seasonal patterns of dengue-like illness were found to be different in the three regions. Among all patients, 271 (37.0%) were virologically confirmed dengue, while 152 (20.8%) patients were diagnosed with probable dengue, giving a total number of 423 (57.8%) dengue patients. Patients' age and clinical manifestations also differed between cities. Mostly, mild dengue fever was observed in Batam, while more severe cases were prominent in Ambon. While all dengue virus (DENV) serotypes were detected, distinct serotypes dominated in different locations: DENV-1 in Batam and Ambon, and DENV-3 in Banjarmasin. We also assessed the diagnostic features in the study sites, which revealed different patterns of diagnostic agreements, particularly in Ambon. To detect the possibility of infection with other arboviruses, further testing on 461 DENV RT-PCR-negative s les was performed using pan-flavivirus and -alphavirus RT-PCRs however, only one chikungunya infection was detected in Ambon. A erse dengue epidemiology in western, central, and eastern Indonesia was observed, which is likely to be influenced by local geographic, climatic, and demographic conditions, as well as differences in the quality of healthcare providers and facilities. Our study adds a new understanding on dengue epidemiology in Indonesia.
Publisher: Springer Science and Business Media LLC
Date: 25-07-2019
Publisher: Bentham Science Publishers Ltd.
Date: 06-02-2020
DOI: 10.2174/2211738507666191210163408
Abstract: Curcumin has been used as a traditional medicine showing antiinflammatory, antimicrobial, and antiviral properties. Despite the promising potentials, curcumin-based drug development is hindered due to its poor solubility and cell uptake. This study aims to produce curcumin nanoemulsion (nanocurcumin) and evaluate its physical characteristics and in vitro cell cytotoxicity and antiviral activity against dengue virus (DENV). Nanocurcumin was generated by self-nanoemulsion technique. Cytotoxicity was determined using MTT assay in A549 cell line. Anti-DENV properties were determined by calculation of inhibitory concentration 50 (IC50) and plaque assay. The resulting nanoemulsion showed uniform droplet size distribution with the average droplet size of 40.85 ± 0.919 nm. Nanocurcumin exhibited higher cell cytotoxicity compared to curcumin solution and may be explained by better cell uptake. Nanocurcumin treatment suppressed DENV growth, although no significant difference observed compared to the curcumin solution counterpart. Greater virus reduction was observed for DENV-1 and DENV-2. The synthesis of nanocurcumin improved curcumin physicochemical properties with potential as antiviral against DENV.
Publisher: Public Library of Science (PLoS)
Date: 21-12-2020
DOI: 10.1371/JOURNAL.PNTD.0008934
Abstract: Chikungunya virus (CHIKV) is an important emerging and re-emerging public health problem worldwide. In Indonesia, where the virus is endemic, epidemiological information from outside of the main islands of Java and Bali is limited. Four hundred and seventy nine acutely febrile patients presenting between September 2017–2019 were recruited from three city hospitals situated in Ambon, Maluku Banjarmasin, Kalimantan and Batam, Batam Island as part of a multi-site observational study. CHIKV RNA was detected in a single serum s le while a separate s le was IgM positive. IgG seroprevalence was also low across all three sites, ranging from 1.4–3.2%. The single RT-PCR positive s le from this study and 24 archived s les collected during other recent outbreaks throughout Indonesia were subjected to complete coding region sequencing to assess the genetic ersity of Indonesian strains. Phylogenetic analysis revealed all to be of a single clade, which was distinct from CHIKV strains recently reported from neighbouring regions including the Philippines and the Pacific Islands. Chikungunya virus strains from recent outbreaks across Indonesia all belong to a single clade. However, low-level seroprevalence and molecular detection of CHIKV across the three study sites appears to contrast with the generally high seroprevalences that have been reported for non-outbreak settings in Java and Bali, and may account for the relative lack of CHIKV epidemiological data from other regions of Indonesia.
Publisher: Elsevier BV
Date: 09-2018
DOI: 10.1016/J.JIPH.2017.09.019
Abstract: Dengue is hyper-endemic in Indonesia. Purwokerto city in Central Java province is routinely ravaged by the disease. Despite the endemicity of dengue in this city, there is still no data on the virological aspects of dengue in the city. We conducted a molecular surveillance study of the circulating dengue viruses (DENV) in Purwokerto city to gain information on the virus origin, serotype and genotype distribution, and phylogenetic characteristics of DENV. A cross-sectional dengue molecular surveillance study was conducted in Purwokerto. Sera were collected from dengue-suspected patients attending three hospitals in the city. Diagnosis was performed using dengue NS1 antigen and IgG/IgM antibodies detection. DENV serotyping was performed using Simplexa Dengue real-time RT-PCR. Sequencing was conducted to obtain full-length DENV Envelope (E) gene sequences, which were then used in phylogenetic and genotypic analyses. Patients' clinical and demographic data were collected and analyzed. A total of 105 dengue-suspected patients' sera were collected, in which 80 (76.2%) were positive for IgM and/or IgG, and 57 (54.2%) were confirmed as dengue by NS1 antigen and/or DENV RNA detection using RT-PCR. Serotyping was successful for 47 isolates. All four serotypes circulated in the area with DENV-3 as the predominant serotype. Phylogenetic analyses grouped the isolates into Genotype I for DENV-1, Cosmopolitan genotype for DENV-2, and Genotype I and II for DENV-3 and -4, respectively. The analyses also revealed the close relatedness of Purwokerto isolates to other DENV strains from Indonesia and neighboring countries. We reveal the molecular and virological characteristics of DENV in Purwokerto, Banyumas regency, Central Java. The genotype and phylogenetic analyses indicate the endemicity of the circulating DENV in the city. Our serotype and genotype data provide references for future dengue molecular epidemiology studies and disease management in the region.
Publisher: Universitas Gadjah Mada
Date: 24-12-2018
Abstract: Indonesia is a tropical country and hyperendemic for dengue. The disease prevalently affected Indonesian and it caused high morbidity and substantial economic burden. This vector-borne viral disease is caused by infection of dengue viruses (DENVs), which are the member of Flaviviridae family. While most of dengue studies in Indonesia focused on the epidemiology, the clinical aspects, the vectors, and to certain extent the virology, there were still gaps in the DENVs genomic aspects. Considering their high mutation rate, the DENVs were known for their high genetic ersity and it might affect the characteristics of the viruses. Comprehensive DENV genomic data were thus important for many aspects of disease management, including virus surveillance, pathogenesis, diagnostics, antiviral drug design, and vaccine development. We established in this study a method for DENV whole genome sequencing using the advanced Next-Generation Sequencing (NGS) and Nextera XT DNA library preparation kit, coupled with simplified bioinformatic analysis methods. The Indonesian DENVs from four serotypes were isolated from patients’ sera, while library was prepared from enriched templates and sequenced using Illumina NGS. Our study highlighted the potential of a robust NGS method in producing whole genome sequence of DENVs, which would be important for future dengue studies.
Publisher: Oxford University Press (OUP)
Date: 16-09-2021
Abstract: Most regions in Indonesia experience annual dengue epidemics. However, the province of East Nusa Tenggara has consistently reported low incidence. We conducted a dengue molecular epidemiology study in Kupang, the capital of the province. Dengue patients were recruited from May 2016 to September 2017. Dengue virus (DENV) screening was performed using NS1 and immunoglobulin G (IgG)/IgM detection. Serotype was determined using reverse transcription polymerase chain reaction and the envelope genes were sequenced to infer the genetic identity and phylogeny. From 119 patients, dengue was confirmed in 62 (52%). Compared with official data, underreporting of dengue incidence was observed. The majority (36%) of patients were children & y of age. Most patients (80%) experienced mild fever. All serotypes were detected, with DENV-3 as the predominant (57%). Kupang DENV-1 isolate was classified as genotype IV, an old and endemic strain, DENV-2 as cosmopolitan, DENV-3 as genotype I and DENV-4 as genotype II. Most isolates showed relatively low evolutionary rates and are closely related with strains from Bali and Timor Leste. The low dengue incidence was most likely caused by sustained local circulation of endemic viruses. This study provides information on the epidemiology of dengue in a low-endemicity setting that should help future mitigation and disease management.
Publisher: Elsevier BV
Date: 10-2020
No related grants have been discovered for Dionisius Denis.