Knowledge among Drug Dispensers and Antimalarial Drug Prescribing Practices in Public Health Facilities in Dar es Salaam.

Irrational prescribing and dispensing of antimalarials has been identified as a contributing factor in the emergence of malaria parasites resistant to existing antimalarial drugs. Factors that contribute to such irrational prescribing and dispensing should therefore be identified to address this problem. The aim of this study was to assess irrational antimalarial drug dispensing and prescribing practices in public health facilities. A descriptive-retrospective cross-sectional study was conducted between January and June 2011 in order to assess prescribing and dispensing practices for antimalarial drugs in three public hospitals and nine health centers in Dar es Salaam, Tanzania. Thirty-two drug dispensers were interviewed using a structured questionnaire. A total of 4,320 prescriptions for the period January to December 2010 were collected and assessed for antimalarial drug prescribing patterns. The majority (84.6%) of drug dispensers had poor knowledge regarding the basic information required from patients before dispensing artemether-lumefantrine. Seventeen of 32 drug dispensers did not know the basic information that should be given to patients in order to increase absorption of artemether-lumefantrine after oral intake. Most drug dispensers also showed limited knowledge about the dosage and contraindications for artemether-lumefantrine. Eighty-seven percent of all prescriptions contained artemether-lumefantrine as the only antimalarial drug, 77.1% contained at least one analgesic, and 26.9% contained at least one antibiotic, indicating unnecessary use of analgesics and antibiotics with antimalarial drugs. A substantial number of prescriptions contained antimalarial drugs that have already been declared ineffective for the treatment of malaria in Tanzania, providing additional evidence of inadequate knowledge among health care workers concerning treatment policy. Despite the government's efforts to increase public awareness regarding use of artemether-lumefantrine as first-line treatment for uncomplicated malaria, there is still irrational prescribing, dispensing, and use of this combination. Based on the results of this study, it is proposed that regular on-the-job training and continuing education be provided to drug dispensers and prescribers in public health facilities

Factors Influencing Prescribing Practices of Medical Practitioners in Public and Private Health Facilities in Dar es Salaam, Tanzania

Purpose: To determine the factors that influence prescribing practices of medical practitioners in public and private health facilities in Dar es Salaam, TanzaniaMethods: One hundred and ninety two (192) medical practitioners from 11 public and 3 private health facilities of Dar es Salaam, Tanzania were interviewed for the criteria they consider when making prescribing decisions. Systematic sampling was used to obtain the required number of medical practitioners working in the hospitals, while for those working in the health centers convenience sampling was used.Results: Medical information from textbooks (64 %) and internet (63 %) were the main sources of prescribing information among medical practitioners. In comparison, medical practitioners in private health facilities (97 %) were more concerned with proven effectiveness of drugs than those working in public health facilities (74.2 %, p = 0.001). Cost of drug to patients was considered much more by practitioners in public health facilities (48.4 %) than their counterparts in private health facilities (24.3 %, p = 0.010). Availability of drugs in the health facility influenced prescribing decisions by a majority of prescribers from public health facilities (53.5 %) than those working in private health facilities (18.9 %, p = 0.000).Conclusion: There are substantial differences between prescribers working in public and private health facilities with regard to the factors which influence their prescribing decisions. In order to promote rational use of medicines, these factors should be considered by health planners when formulating policies and allocating resources in health facilities.Keywords: Prescribing practice, Medical practitioners, Health facilities, Prescribing information, Drug costs, Rational use, Drug effectivenes

Photodynamic therapy and tumor imaging of hypericin-treated squamous cell carcinoma

BACKGROUND: Conventional cancer therapy including surgery, radiation, and chemotherapy often are physically debilitating and largely ineffective in previously treated patients with recurrent head and neck squamous cell carcinoma (SCC). A natural photochemical, hypericin, could be a less invasive method for laser photodynamic therapy (PDT) of these recurrent head and neck malignancies. Hypericin has powerful photo-oxidizing ability, tumor localization properties, and fluorescent imaging capabilities as well as minimal dark toxicity. The current study defined hypericin PDT in vitro with human SCC cells before the cells were grown as tumor transplants in nude mice and tested as a model for hypericin induced tumor fluorescence and PDT via laser fiberoptics. METHODS: SNU squamous carcinoma cells were grown in tissue culture, detached from monolayers with trypsin, and incubated with 0.1 μg to 10 μg/ml of hypericin before exposure to laser light at 514, 550, or 593 nm to define optimal dose, time, and wavelength for PDT of tumor cells. The SCC cells also were injected subcutaneously in nude mice and grown for 6–8 weeks to form tumors before hypericin injection and insertion of fiberoptics from a KTP532 surgical laser to assess the feasibility of this operating room instrument in stimulating fluorescence and PDT of tumors. RESULTS: In vitro testing revealed a hypericin dose of 0.2–0.5 μg/ml was needed for PDT of the SCC cells with an optimal tumoricidal response seen at the 593 nm light absorption maximum. In vivo tumor retention of injected hypericin was seen for 7 to10 days using KTP532 laser induced fluorescence and biweekly PDT via laser fiberoptics led to regression of SCC tumor transplants under 0.4 cm(2 )diameter, but resulted in progression of larger size tumors in the nude mice. CONCLUSION: In this preclinical study, hypericin was tested for 514–593 nm dye laser PDT of human SCC cells in vitro and for KTP532 surgical laser targeting of SCC tumors in mice. The results suggest hypericin is a potent tumor imaging agent using this surgical laser that may prove useful in defining tumor margins and possibly in sterilizing post-resection margins. Deeply penetrating pulsed infrared laser emissions will be needed for PDT of larger and more inaccessible tumors

Elucidation of the tumoritropic principle of hypericin

Hypericin is a potent agent in the photodynamic therapy of cancers. To better understand its tumoritropic behaviour, we evaluated the major determinants of the accumulation and dispersion of hypericin in subcutaneously growing mouse tumours. A rapid exponential decay in tumour accumulation of hypericin as a function of tumour weight was observed for each of the six tumour models investigated, and a similar relationship was found between tumour blood flow and tumour weight. Moreover, there was a close correlation between the higher hypericin uptake in RIF-1 tumours compared to R1 tumours and tumour vessel permeability. To define the role of lipoproteins in the transport of hypericin through the interstitial space, we performed a visual and quantitative analysis of the colocalisation of hypericin and DiOC18-labelled lipoproteins in microscopic fluorescent overlay images. A coupled dynamic behaviour was found early after injection (normalised fluorescence intensity differences were on the whole less than 10%), while a shifted pattern in localisation of hypericin and DiOC18 was seen after 24 h, suggesting that during its migration through the tumour mass, hypericin is released from the lipoprotein complex. In conclusion, we were able to show that the tumour accumulation of hypericin is critically determined by a combination of biological (blood flow, vessel permeability) and physicochemical elements (affinity for interstitial constituents)

Antibacterial activity of some selected medicinal plants of Pakistan

<p>Abstract</p> <p>Background</p> <p>Screening of the ethnobotenical plants is a pre-requisite to evaluate their therapeutic potential and it can lead to the isolation of new bioactive compounds.</p> <p>Methods</p> <p>The crude extracts and fractions of six medicinal important plants (<it>Arisaema flavum</it>, <it>Debregeasia salicifolia</it>, <it>Carissa opaca</it>, <it>Pistacia integerrima</it>, <it>Aesculus indica</it>, and <it>Toona ciliata</it>) were tested against three Gram positive and two Gram negative ATCC bacterial species using the agar well diffusion method.</p> <p>Results</p> <p>The crude extract of <it>P. integerrima </it>and <it>A. indica </it>were active against all tested bacterial strains (12-23 mm zone of inhibition). Other four plant's crude extracts (<it>Arisaema flavum</it>, <it>Debregeasia salicifolia</it>, <it>Carissa opaca</it>, and <it>Toona ciliata</it>) were active against different bacterial strains. The crude extracts showed varying level of bactericidal activity. The aqueous fractions of <it>A. indica </it>and <it>P. integerrima </it>crude extract showed maximum activity (19.66 and 16 mm, respectively) against <it>B. subtilis</it>, while the chloroform fractions of <it>T. ciliata </it>and <it>D. salicifolia </it>presented good antibacterial activities (13-17 mm zone of inhibition) against all the bacterial cultures tested.</p> <p>Conclusion</p> <p>The methanol fraction of <it>Pistacia integerrima</it>, chloroform fractions of <it>Debregeasia salicifolia </it>&<it>Toona ciliata </it>and aqueous fraction of <it>Aesculus indica </it>are suitable candidates for the development of novel antibacterial compounds.</p

Antimalarial Drugs for Pediatrics - Prescribing and Dispensing Practices in a Tanzanian City

Purpose: To assess dispensing and prescribing practices with regard to antimalarial drugs for pediatrics in private pharmacies and public hospitals in Dar es Salaam, Tanzania. Methods: This was a cross-sectional, descriptive study that assessed the knowledge and practice of 200 drug dispensers in the private community pharmacies in Dar es Salaam. Two hundred (200) parents of children seeking malaria treatment were also interviewed at the public hospitals. Results: A majority of drug dispensers had moderate (63.3 %) to low knowledge (36.7 %) regarding antimalarial drug use in pediatrics. Parents had moderate (67 %) to low (33 %) level of understanding of the instructions given to them by the prescribers regarding administration of antimalarial drugs to pediatrics at home. Most children were not weighed, and there were indications of wrong calculations of doses of antimalarials in pediatrics. Conclusion: Overall, there were irrational dispensing and prescribing of antimalarial drugs to pediatrics. Since malaria is a major killer disease in Tanzania, especially in children under five years of age, there is a need to institute measures to ensure rational prescribing, dispensing and use of antimalarial drugs in pediatrics

In vitro transport and uptake of protohypericin and hypericin in the Caco-2 model

The intestinal absorption characteristics of protohypericin, a protonaphthodianthrone present in Hypericum extract, were studied and compared with those of hypericin. The Caco-2 model was used as a model of the intestinal mucosa to assess transepithelial transport and cell uptake. The experimental work was performed in specific light conditions that prevented both the photoconversion of protohypericin into hypericin and the photosensitization of the cells. Following application of the individual compounds (80-200 microM) to the apical side of the monolayers, the appearance in the basolateral compartment was found to be very low (<0.5%/5 h), but was comparable for both compounds. A lag-time of 2-3 h was observed, suggesting gradual saturation of binding sites on the membrane or inside the cells. Uptake experiments of protohypericin and hypericin by Caco-2 cells revealed a very significant cellular accumulation (4-8%); uptake was characterised by saturation after 3 h. The findings of this study suggest that protohypericin has comparable absorption characteristics as hypericin and may contribute to the beneficial effect of Hypericum extract after oral dosing.status: publishe

Intermittent Preventive Therapy and Treatment of Malaria during Pregnancy: A Study of Knowledge among Pregnant Women in Rufiji District, Southern Tanzania

Purpose: To assess the knowledge and awareness of pregnant women regarding the use of sulfadoxinepyrimethamine (SP) for intermittent preventive therapy (IPT) and artemether-lumefantrine (ALu) for treatment of malaria during pregnancy. Methods: The study was conducted in Rufiji district, southern Tanzania from March 2011 to September 2011. Four hundred and seventy (470) pregnant women in their second and third trimesters were interviewed when attending antenatal clinics at the selected hospitals, health centers and dispensaries. Focus group discussions (FGDs) were also conducted with 46 pregnant women at the health facilities in the district. Results: More than half (54.3 %) of pregnant women did not know if SP it was used for IPT. Most women (76.6 %) did not know the use of SP for IPT in relationship with gestation age. Overall, the results show that most women had very low knowledge about the use of SP for IPT. Forty three (9.1 %) pregnant women reported to have had malaria during their current pregnancies. The antimalarials reported to be used by pregnant women were quinine 18(42.9 %), SP (23.8 %), ALu (21.4%) and sulphamethoxyprazinepyrimethamine (2.4%). Irrespective of the gestation age of pregnancy, almost all (98.3 %) pregnant women perceived ALu as unsafe drug to be used during pregnancy. Conclusion: Most pregnant women had minimum knowledge about the use and benefits of SP for IPT and ALu for treatment of malaria during pregnancy. Some erroneous beliefs about the safety of ALu during pregnancy were also identified among pregnant women. For effective implementation of IPT policy and treatment of malaria during pregnancy, pregnant women should be sensitized and educated on the use and benefits of antimalarial drugs