High incidence of Plasmodium knowlesi malaria compared to other human malaria species in several hospitals in Malaysia

@# Through the regional control programme, Malaysia has been successfully reducing the incidence of Plasmodium falciparum and Plasmodium vivax infections. However, the incidence of zoonotic malaria Plasmodium knowlesi infection is increasing and now has been the major cause of malaria in Malaysia especially Malaysian Borneo. The emergence of knowlesi infection has threatened the malaria elimination programme which the government aims to reduce the overall malaria infections by 2020. Unlike other benign human Plasmodium spp., P. knowlesi can cause fatal infections. The aim of this study was to determine the incidence and distribution of five human malaria parasites including P. knowlesi in Peninsular Malaysia and Malaysian Borneo. A total of 112 blood samples were collected from seven states and district hospitals in Peninsular Malaysia and Malaysian Borneo from year 2015 to 2016. The samples were examined by microscopy and further confirmed by nested PCR assay targeting 18S rRNA gene of Plasmodium spp. Following the nested PCR assays, a total of 54 (48.2%) samples were positive for P. knowlesi infections, 12 (10.7%) cases were positive for P. vivax infections, followed by 7 (6.3%) cases of P. falciparum and 4 (3.5%) cases of P. malariae. There were 3 cases (2.7%) of mixed infections (P. knowlesi/P. vivax). However, no cases were identified as P. ovale. A total of 32 (28.6%) cases were found as negative infections. LoopMediated Isothermal Amplification Assay (LAMP) was performed to confirm inconclusive results produced by microscopy and nested PCR. P. knowlesi showed the highest prevalence in Sarawak (n= 30), Sabah (n=13), Pulau Pinang (n=5) and Pahang (n=6). PCR and LAMP was not able to detect a large number of microscopy positive samples due to DNA degradation during storage and shipping. Among all the states involved in this study, the highest prevalence of P. knowlesi infection was found in Sabah and Sarawak.

Soil-transmitted helminth infections among malaria patients determined by microscopy and real-time PCR methods at two district hospitals in Sarawak, Malaysia

Malaria is still endemic in Sarawak and Sabah. Numerous studies have indicated that patients with malaria are commonly co-infected with helminthes particularly in endemic regions. The aim of this study was to investigate the incidence of soil-transmitted helminth (STH) infection among malaria patients using microscopy and multiplex real-time PCR at two district hospitals in Sarawak. A total of 94 patients who were clinically-suspected to have malaria were confirmed to be infected by both microscopy and multiplex real-time PCR. By the molecular method, 23.4%, 74.5% and 2.1% of the samples were positive for Plasmodium falciparum, P. vivax and mixed P. falciparum and P. vivax, respectively. Among the malaria patients, 48.9% were found to be co-infected with STHs. In comparison, microscopic examinations showed that 6.4% of the malaria patients were infected with STHs. From the real-time PCR positive samples, 31.9% had single helminth infections while 17% had mixed infections. In conclusion, this study showed that almost half of the malaria patients at the two Sarawak hospitals were co-infected with helminth. Future studies should be specifically designed to determine if there is any correlation between the two infections in terms of incidence and intensity.

Optimal protein extraction methods from diverse sample types for protein profiling by using Two-Dimensional Electrophoresis (2DE)

There is a great diversity of protein samples types and origins, therefore the optimal procedure for each sample type must be determined empirically. In order to obtain a reproducible and complete sample presentation which view as many proteins as possible on the desired 2DE gel, it is critical to perform additional sample preparation steps to improve the quality of the final results, yet without selectively losing the proteins. To address this, we developed a general method that is suitable for diverse sample types based on phenolchloroform extraction method (represented by TRI reagent). This method was found to yield good results when used to analyze human breast cancer cell line (MCF-7), Vibrio cholerae, Cryptocaryon irritans cyst and liver abscess fat tissue. These types represent cell line, bacteria, parasite cyst and pus respectively. For each type of samples, several attempts were made to methodically compare protein isolation methods using TRI-reagent Kit, EasyBlue Kit, PRO-PREPTM Protein Extraction Solution and lysis buffer. The most useful protocol allows the extraction and separation of a wide diversity of protein samples that is reproducible among repeated experiments. Our results demonstrated that the modified TRI-reagent Kit had the highest protein yield as well as the greatest number of total proteins spots count for all type of samples. Distinctive differences in spot patterns were also observed in the 2DE gel of different extraction methods used for each type of sample.

Adjuvant treatment in colorectal cancer. Experience from a referral center in eastern peninsular Malaysia.

BACKGROUND: Colorectal cancer is one of the most common malignancies in the West, but in Asia the incidence is low. However in Malaysia, colorectal cancer is increasing with a reported figure of 15% of all cancer cases. Adjuvant chemo and radiotherapy are now more frequently used in such patients. The present retrospective analysis was performed to document the effect of such therapy among patients with colorectal cancer in Malaysia. MATERIALS AND METHODS: This is a retrospective study on the use of adjuvant treatment in colorectal cancers. Patients with histopathological evidence of risk factors were subjected to adjuvant radiotherapy and/or chemotherapy. Cancers confined to rectum and rectosigmoid were subjected to pelvic radiotherapy to a tumor dose of 45 Gy in 20 fractions over 4-week period. 5-flurouracil based chemotherapy was predominantly offered for colonic cancers. RESULTS: One hundred thirty patients with colorectal cancers received adjuvant treatment with a median age of 58 years (range 22-76 years). The male to female ratio was 1.4:1. There were 76% Malays, 19% Chinese, 2% Indians and 3% Siamese subjects in this study. Modified Dukes' stage B2 (28%) and C (38%) constituted the majority, which were distributed in rectum (40%), rectosigmoid (19%), and in the remaining colon (41%). Thirty-one patients received 5-fluorouracil with folinic acid based regime and 35 patients received 5-fluorouracil with levamisole based regimen. Locoregional radiotherapy was offered to 56 (43%) patients. Following treatment, the 2-year actuarial survival was 28% and 54% in colon and rectum cancer respectively. CONCLUSIONS: This study showed that colorectal cancer is not infrequent among Malays in this region and rectal cancers had better survival than the colonic cancers.