Asian Pacific Journal of Tropical Medicine

253-258

Authors: Anthony A Attama, Collins N Igbonekwu

Objective To formulate and evaluate in vitro, surface-modified solid lipid microspheres containing halofantrine using lipid matrix formed from goat fat and a phospholipid (P90H). Methods The model drug, halofantrine in an increasing concentration of 1%, 2%, 3%, 4% and 5% w/w was incorporated into surface-modified solid lipid microspheres formulated by hot homogenization. Effect of drug concentration on the encapsulation efficiency was studied. The dispersion was evaluated using particle size, particle morphology, pH and encapsulation efficiency. The drug formulation with highest encapsulation efficiency was selected and used for the release studies and compared with the release from a commercial dosage form (Halfan® 250 mg tablet, Glaxo-Smithkline, Mayenne France) using simulated gastric fluid (SGF pH 1.2), simulated intestinal fluid (SIF pH 7.2) and phosphate buffer (pH 6.8) as biorelevant media. Results were analyzed statistically and the level of significance was taken to be P < 0.05). Results Discrete and spherical solid lipid microspheres were produced. The particle size of the dispersion was low (32.48–33.87 μm) with minimal particle growth and high encapsulation efficiencies (86.8%–91.0%) after 3 months. The pH of the microspheres dispersion changed appreciably after 3 months. In vitro release result obtained revealed sustained and controlled drug release from the lipid microspheres compared with the tablet dosage form. Conclusions Formulation of halofantrine as solid lipid microspheres presents a better alternative to the conventional tablet formulation as the in vitro dissolution of the highly lipophilic halofantrine was highly improved.

266-270

Authors: Qiang Wu, Peng Zhou, Shiyun Qian, Xi Qin, Zhigang Fan, Qiongyao Fu, Zhinong Zhan, Hua Pei

Objective To clone and express Rv3265c gene of Mycobacterium tuberculosis in Escherichia coli (E. coli) under optimistic conditions, obtain and identify protein expressed, analyze the structure and characteristics of the protein using bioinformatics methods for future applications. Methods Rv3265c gene from Mycobacterium tuberculosis H37Rv was amplified by polymerase chain reaction, and was cloned into the pET-30a vector after purification and recovery. The recombinant plasmid was sequenced and expressed in E. coli BL21(DE3), and then purified and identified by western blotting. The essential physical-chemical properties of the protein were predicated by bioinformatics tools, including subcellular location, secondary structure, domains, antigenic epitopes, etc. Tertiary structure of the protein based on homology modeling was established, while multi-sequence homological alignment and phylogenetic analysis were proformed. Results The recombinant protein was obtained in soluble fraction from expression system in E. coli BL21(DE3) carrying pET30- Rv3265c plasmid, and Rv3265c gene was expressed correctly. Bioinformatics analysis showed the protein contained no signal peptide and transmembrane helices, located outside of membrane. Secondary structure analysis revealed it contained α-helix, extended strand and random coil, 46.8%, 14.6%, 38.6%, respectively. Furthermore, it possessed six potential antigenic epitopes, one glycosyl transferase domain. A simple three-dimensional model of this protein was constructed by Swiss-model sever. Both sequences and structures were conservative and especial either in gene or in protein. Conclusions Rv3265c gene might be a desirable molecular target for anti-tuberculosis drug and vaccine. The purified protein from expression will be utilized to study the kinetics of L-rhamnosyltransferase and to develope an enzyme assay for screening vaccine or drug.

275-277

Authors: Ximin Hu, Jianwei Du, Chongjin Tong, Shanqing Wang, Jian Liu, Yuchun Li, Changhua He

Objective To understand the current epidemiological status of Angiostrongylus cantonensis in Hainan island and provide the scientific evidences for prevention and control of the disease. Methods The investigation on nature infection condition of intermediate hosts and final hosts of Angiostrongylus cantonensis were carried out in five counties, Hainan Province, and enzyme linked immunosorbent assay (ELISA) was employed to detect antibodies of Angiostrongylus cantonensis in human hosts. Results A total of 1612 molluscs were examined, 21.3% of which harbored L3 of Angiostrongylus cantonensis. Among them, the infection rates of Pomacea canaliculata, Achatina fulica, Cepaea and Phlegm bilineatus were 12.36%(64/518), 22.66%(121/534), 20.93%(9/43), and 28.24%(146/517), respectively. Of the 118 rats trapped, 13 Rattus norvegicus were found to be infected with Angiostrongylus cantonensis. A total of 459 serum samples were collected and tested. 92 serum samples were Angiostrongylus cantonensis antibody-positive. Conclusions The survey revealed a wide distribution of Angiostrongylus cantonensis in Hainan island. Pomacea canaliculata and Achatina fulica are main intermediate hosts of Angiostrongylus cantonensis. Rattus novegicus is a nature definitive host, indicating that a considerable number of people are at risk of angiostrongyliasis. Health education, rigorous food inspection and surveillance are all needed to prevent angiostrongyliasis outbreaks in future.

283-287

Authors: Tolulope O Ajala, Cecilia I Igwilo, Ibrahim A Oreagba, Oluwatoyin A Odeku

Objective To investigate the antiplasmodial activity of the extracts of Phyllanthus amarus (P. amarus) on Plasmodium yoelii (P. yoelii) (a resistant malaria parasite strain used in animal studies) infection in mice. Methods The aqueous and ethanol extracts of the whole plant of Phyllanthus amarus was administered to Swiss albino mice at doses of 200 mg/kg/day, 400 mg/kg/day, 800 mg/kg/day and 1600 mg/kg/day and the prophylactic and chemotherapeutic effect of the extracts against P. yoelii infection in mice was investigated and compared with those of standard antimalaria drugs used in the treatment of malaria parasite infection. Acute toxicity test was carried out in mice to determine the safety of the plant extract when administered orally. Results The results showed that the extracts demonstrated a dose—dependent prophylactic and chemotherapeutic activity with the aqueous extracts showing slightly higher effect than the ethanol extract. The antiplasmodial effects of the extracts were comparable to the standard prophylactic and chemotherapeutic drugs used in chloroquine resistant Plasmodium infection although the activity depended on the dose of the extract administered. The extracts showed prophylactic effect by significantly delaying the onset of infection with the suppression of 79% at a dose of 1600 mg/kg/day. Conclusions The results obtained indicate that the extracts of the whole plant of P. amarus possess repository and chemotherapeutic effects against resistant strains of P. yoelii in Swiss albino mice. The findings justify the use of the extract of P. amarus in traditional medicine practice, for the treatment of malaria infections.

294-300

Authors: S Rajan, T Thirunalasundari, S Jeeva

Objective To evaluate the phytochemical and anti-bacterial efficacy of the seed kernel extract of Mangifera indica (M. indica) against the enteropathogen, Shigella dysenteriae (S. dysenteriae), isolated from the diarrhoeal stool specimens. Methods The preliminary phytochemical screening was performed by the standard methods as described by Harborne. Cold extraction method was employed to extract the bioactive compounds from mango seed kernel. Disc diffusion method was adopted to screen antibacterial activity. Minimum inhibitory concentration (MIC) was evaluated by agar dilution method. The crude extracts were partially purified by thin layer chromatography (TLC) and the fractions were analyzed by high performance thin layer chromatography (HPTLC) to identify the bioactive compounds. Results Phytochemical scrutiny of M. indica indicated the presence of phytochemical constituents such as alkaloids, gums, flavanoids, phenols, saponins, steroids, tannins and xanthoproteins. Antibacterial activity was observed in two crude extracts and various fractions viz. hexane, benzene, chloroform, methanol and water. MIC of methanol fraction was found to be (95±11.8) μg/mL. MIC of other fractions ranged from 130–380 μg/mL. Conclusions The present study confirmed that each crude extracts and fractions of M. indica have significant antimicrobial activity against the isolated pathogen S. dysenteriae. The antibacterial activity may be due to the phytochemical constituents of the mango seed kernel. The phytochemical tannin could be the reason for its antibacterial activity.

305-309

Authors: Subramanian Bragadeeswaran, Selvam Priyadharshini, Kolandhasamy Prabhu, Solomon Raj Sophia Rani

Objective To study the antimicrobial, hemolytic activity and immunomodulatory activity of fish epidermal mucus and their chemical constituents from Cynoglossus arel (C. arel) and Arius caelatus (A. caelatus). Mucus plays an important role in the prevention of colonization by parasites, bacteria and fungi. Methods Epidermal mucus was obtained from two marine fishes, lyophilized and the chemical composition of epidermal mucus was analysed by FT-IR analysis. The in vitro antimicrobial activity against human pathogens (fungi, gram positive and gram-negative bacteria) and also the hemolytic activity and immunomodulatory activity were determined. Results Totally ten human pathogens were tested against the fish mucus. Out of the ten pathogens, five pathogens have proved to be sensitive to the mucus. Maximum zone of inhibition was observed against Vibrio cholera (V. cholera) (9 mm and 2 mm in diameter), followed by Staphylococcus aureus (S. aureus) with a inhibition zone of (6 mm and 3 mm), Streptococcus areus (S. areus) (5 mm and 4 mm), Vibrio parahemolyticus (V. parahemolyticus) (4 mm and 5 mm) respectively. Conclusions The present investigation has revealed that positive progresses in the fish mucus extracts against human pathogens and hemolytic activity. But further efforts are required for the purification and isolation of the active antimicrobial compounds in order to establish their possible applications.

315-319

Authors: Iquo B Otu-Bassey, Monday F Useh, Anyanwu A Alaribe

Objective To investigate the relationship between enterobiasis and enuresis before and after albendazole therapy among 632 children, aged, 5–14 years, in Calabar, Nigeria. Methods The scotch tape (cellotape) technique was used for the detection of eggs of Enterobius vermicularis (E. vermicularis) while questionnaire-based interviews were used for screening for anal itching and/or enuresis among study participants. All subjects found positive for Enterobius infection as confirmed by the presence of eggs and those with persistent anal itching (both enuretic and non-enuretic) were treated with 400 mg of albendazole given as a single dose. The treated subjects were re-assessed post-treatment to ascertain whether they were cured and also to determine their enuretic status (for the enuretics). Results The overall prevalences of Enterobius infection, anal itching, and enuresis prior to albendazole therapy were 6.8%, 42.9%, and 35.6% respectively. There was no statistically significant difference in the prevalence of these parameters by the socio-economic class of subjects (P = 0.462, P = 0.647, and P = 0.610, respectively). The pre-treatment prevalences of enuresis among Enterobius and anal itching-positive subjects were 53.5% and 49.8%, respectively versus 34.3% and 24.9%, respectively among their negative counterpart (P = 0.012 and P < 0.001, respectively). Four (20%) out of the 20 enuretic children found Enterobius egg-negative after albendazole therapy were equally cured while 8(40%) had reduction of their enuresis, thus giving a total resolution rate of 60%. Similarly, 64.2% resolution (25% cure and 32.8% reduction) of enuresis was observed amongst 120 anal itching-cured/enuretic children. Enuretic status of the Enterobius-/anal itching-uncured subjects, on the other hand, remained unchanged post-treatment. Conclusions This study is suggestive of the involvement of E. vermicularis in the aetiology of enuresis in Calabar. Children presenting with, especially, uncomplicated enuresis should be screened for enterobiasis.

323-324

Authors: Rajat Jhamb, Bineeta Kashyap, GS Ranga, A Kumar

Dengue fever (DF) and dengue haemorrhagic fever (DHF) are important mosquito-borne viral diseases of humans and recognized as important emerging infectious diseases in the tropics and subtropics. Compared to nine reporting countries in the 1950s, today the geographic distribution includes more than 100 countries worldwide. Dengue viral infections are known to present a diverse clinical spectrum, ranging from asymptomatic illness to fatal dengue shock syndrome. Mild hepatic dysfunction in dengue haemorrhagic fever is usual. However, its presentation as acute liver failure (ALF) is unusual. We report a patient with dengue shock syndrome who presented with acute liver failure and hepatic encephalopathy in a recent outbreak of dengue fever in Delhi, India.

328-329

Authors: Shamma Arora, Naveen Gupta, Ashwani Kumar, IR Kaur

Non typhoidal Salmonella species are thought to be potentially infectious to humans. We isolated Salmonella enteritidis from a 10-year-old boy with fever and thrombocytopenia. We reviewed the literature concerning infections caused by Salmonella but we could not find any such case report from India.