Development of diethylcarbamazine-loaded poly(caprolactone) nanoparticles for anti-inflammatory purpose: Preparation and characterization

Abstract Diethylcarbamazine-loaded nanoparticles were previously evaluated for their anti-inflammatory activity. However, little is known regarding their physicochemical properties. Thus, the purpose of this study was to physiochemically characterize diethylcarbamazine-loaded poly(caprolactone) nanoparticles and evaluate their in vitro cytotoxicity. All formulations were prepared using the double-emulsion method. The average particle size was in the ranged between 298 and 364 nm and the polydispersity indexes were below 0.3. The zeta potential values were marginally negative, which may be related to drug loading, as higher loading led to an increase in the modulus of the zeta potential values. Fourier transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD) analysis did not reveal any chemical interactions between the chemicals used and the absence of drug in crystalline form on the nanoparticle surfaces. The in vitro drug release study revealed a concentration-dependent release from the nanoparticles into the medium. The in vitro cytotoxicity assay demonstrated the biocompatibility of the blank and loaded nanoparticles. Hence, all formulations presented good physicochemical and safety properties, corroborating the in vivo anti-inflammatory activity, previously reported by our group.

Development Of Hplc Method For Stress Testing Of Combination Of Two Drugs Using Design Of Experiment Concept

This study was conducted to develop, an High Performance Liquid Chromatography using photodiode array detector (HPLC-PDA) method to analyse the samples generated by the stress testing of antifilarial combination (albendazole and diethylcarbamazine citrate) in the solution state. The concept of Quality by Design (Design of Experiment, DoE) approach was used for the development. For the separation of the drugs and its degradation products (DPs), DoE was applied in two stages, i.e., primary parameter stage where factors having major effect were selected. This stage gives us CQA (Critical Quality Attribute) which along with minor factors affecting were varied to get the secondary design. For each of the stage a different design was selected; for primary stage IV optimal design (Response Surface Method) was selected whereas for secondary stage, Taguchi orthogonal array design was selected. The major primary parameters affecting the HPLC method as screened by preliminary studies were the buffer pH, organic modifier (methanol or acetonitrile), initial hold time (start of gradient) and gradient time. The primary stage was completed successfully. The results were compiled in form of resolution of peak from next peak and analysed by DoE. The process fixed the values for buffer pH (4.38), organic modifier (acetonitrile) and gradient time (30 min). The CQA from primary run was initial hold time. This parameter along with other parameters: initial and final concentration of organic modifier, buffer type (phosphate or acetate), buffer strength (mM) and oven temperature were further varied and samples withdrawn were analysed. The data of secondary design was compiled in the form of resolution (R), analysed by Design Expert and final value for secondary parameter for HPLC method were fixed. The resolution of the peaks for some secondary runs was sufficient reflecting some type of interaction between the drugs and/or degradation products.

Lymphatic Filariasis Presenting as a Swelling over the Upper Arm: A Case Report

@#Filariasis continues to be one of the endemic problemsworldwide with 40% of the cases in India. We report a caseof lymphatic filariasis in a 32-year old female who presentedwith a non-tender swelling over left upper arm. Bloodsample showed no eosinophilia while the FNAC wasdiagnostic of W. bancrofti. Patient responded well with oraldiethylcarbamazine. High index of suspicion of filariasis isindicated when dealing with a swelling of unknown causeespecially in filariasis endemic areas.

Impact on prevalence of intestinal helminth infection in school children administered with seven annual rounds of diethyl carbamazine (DEC) with albendazole.

Background & objectives: One third of the world’s population is infected with one or more of the most common soil-transmitted helminths (STH). Albendazole (ALB) is being administered with diethyl carbamazine (DEC) in filariasis endemic areas to eliminate lymphatic filariasis (LF) and helminth infections. In this study, the cumulative impact of seven annual rounds of mass drug administrations (MDA) of DEC and ALB on STH infection in school children in selected villages in southern India was determined. Methods: During 2001-2010, seven MDAs were implemented by the Tamil Nadu state health department, India. LF and STH infections were monitored in school children from 18 villages of the two treatment arms (viz, DEC alone and DEC+ALB). Kato-Katz cellophane quantitative thick smear technique was employed to estimate STH infections at three weeks, six months and one year post MDA. Results: Prior to treatment, an overall STH prevalence was 60 per cent. After each MDA, infection markedly reduced at three weeks post-treatment in both the arms. The prevalence increased at six months period, which was maintained up to one year. After seven rounds of MDA, the infection reduced from 60.44 to 12.48 per cent in DEC+ALB arm; while the reduction was negligible in DEC alone arm (58.77 to 52.70%). Interpretation & conclusions: Seven rounds of MDA with DEC+ALB reduced the infection load significantly, and further sustained low level of infection for 10 years. However, complete parasite elimination could not be achieved. To curtail STH infection in the community, MDA should be regularized and environmental sanitation measures need to be improved by effective community-based campaigns.

Titrimetric and spectrophotometric assay of diethylcarbamazine citrate in formulations using iodate and iodide mixture as reagents

One titrimetric and two spectrophotometric methods are proposed for the determination of diethylcarbamazine citrate (DEC) in bulk drug and in formulations using potassium iodate and potassium iodide as reagent. The methods employ the well-known analytical reaction between iodate and iodide in the presence of acid. In titrimetry (method A), the drug was treated with a measured excess of thiosulfate in the presence of unmeasured excess of iodate-iodide mixture and after a standing time of 10 min, the surplus thiosulfate was determined by back titration with iodine towards starch end point. Titrimetric assay is based on a 1:3 reaction stoichiometry between DEC and iodine and the method is applicable over 2.0-10.0 mg range. The liberated iodine is measured spectrophotometrically at 370 nm (method B) or the iodine-starch complex measured at 570 nm (method C). In both methods, the absorbance is found to be linearly dependent on the concentration of iodine, which in turn is related to DEC concentration. The calibration curves are linear over 2.5-50 and 2.5-30 µg mL-1 DEC for method B and method C, respectively. The calculated molar absorptivity and Sandell sensitivity values were 6.48×103 L mol-1 cm-1 and 0.0604 µg cm-2, respectively, for method B, and their respective values for method C are 9.96×103 L mol-1 cm-1 and 0.0393 µg cm-2. The intra-day and inter-day accuracy and precision studies were carried out according to the ICH guidelines. The methods were successfully applied to the analysis of DEC formulations.

Propõem-se titulação e dois métodos espectrofotométricos para a determinação de citrato de dietilcarbamazina (DEC) a granel e em suas formulações, usando iodato de potássio e iodeto de potássio como reagente. Os métodos utilizam a reação analítica conhecida entre iodato e iodeto, na presença de ácido. Na titulometria (Método A), o fármaco foi tratado com excesso medido de tiossulfato, na presença de excesso não medido de mistura iodato-iodeto e, depois de um tempo de repouso de 10 min, o excesso de tiossulfato foi determinado por titulação de retorno com iodo até o ponto final com amido. A titulação é baseada em reação com estequiometria 1:3 entre DEC e iodo e o método é aplicável na faixa de 2.0-10.0 mg. O iodo liberado é medido espectrofotometricamente a 370 nm (método B) ou o complexo de iodo-amido medido a 570 nm (método C). Em ambos os métodos, a absorvância é considerada linearmente dependente da concentração de iodo, a qual, por sua vez, está relacionada à concentração de DEC. As curvas de calibração são lineares para concentrações de DEC de 2.5-50 e 2.5-30 mg mL- 1 para o método B e para o método C, respectivamente. A absortividade molar calculada e os valores de sensibilidade Sandel foram 6.48×103 L mol-1 cm- 1 e 0.0604 ug cm-2, respectivamente, para o método B, e os seus respectivos valores para o método C são 9.96×103 L mol-1 cm-1 e 0.0393 mg cm-2. Os estudos de exatidão e precisão intra-dia e inter-dia foram realizados de acordo com as diretrizes da ICH. Os métodos foram aplicados com sucesso na análise de formulações de DEC.

A Case of Chronic Cough with Progressive Breathlessness in a 32 Year-old Male Health worker- Tuberculosis?, Allergic Bronchitis? Asthma?

Introduction: Although tuberculosis is hyper-endemic in India and is responsible for a huge proportion of respiratory morbidity, adequate workup should be conducted to rule out other differential diagnosis wherever applicable. Case Report: A 32 year old male health worker was suffering from productive cough and gradually increasing breathlessness since three months. The investigations conducted were a sputum analysis and a chest x-ray, both of which were normal and hence he was treated as a case of allergic bronchitis. Subject presented to us after three months with no relief. We further investigated him and found severe eosinophilia in the peripheral blood, a positive anti-filarial antibody and a negative triple stool test for ova and parasites. He was treated with diethylcarbamazine and albendazole+ivermectin combination. The patient responded well and had no complaints at the end of the 4 week treatment. Discussion and Conclusion: The subject should have been evaluated by conducting a basic investigation like a complete blood count. Delay in treatment of cases of tropical pulmonary eosinophilia can lead to permanent respiratory morbidity.

The Global Programme to Eliminate Lymphatic Filariasis: History and achievements with special reference to annual single-dose treatment with diethylcarbamazine in Samoa and Fiji

Diethylcarbamazine (DEC), first introduced in 1947, was shown to have strong efficacy and safety for treatment of human lymphatic filariasis, which is caused mostly by a species <I>Wuchereria bancrofti.</I> Many studies to optimize the dosage and treatment schedule of DEC followed, and, based on the results, control programs with various regimens were implemented in different endemic areas⁄countries. By the mid 1970s, with endorsement by the WHO Expert Committee on Filariasis (3rd report, 1974), the standard DEC regimen for <I>W. bancrofti</I> infection in mass treatment had been established in principle: a total dose of 72 mg⁄kg of body weight given in 12 divided doses, once weekly or monthly, at 6 mg⁄kg each. Not long after the committee report, the efficacy of annual single-dose treatment at 6 mg⁄kg, which is only one twelfth of the WHO-recommended dose in a year, was reported effective in French Polynesia (study period: 1973-78), and later in Samoa (study period: 1979-81). These results were published between 1978 and 1985 in the Bulletin of WHO but received little attention. In the mid 1980s, the efficacy of ivermectin, the first-choice drug for onchocerciasis, against lymphatic filariae came to light. Since the effect at a single dose was remarkable, and often better than DEC, it was predicted that the newly introduced drug would replace DEC. Treatment experiments with ivermectin increased quickly in number. Meanwhile, annual single-dose mass drug administration (MDA) with DEC at 6 mg⁄kg was under scrutiny in Samoa and Fiji. In the early 1990s, the Samoan study, which covered the entire population of 160,000 with 3 annual MDAs, reported a significant reduction in microfilaria (mf) prevalence and mean mf density, while in Fiji, the efficacy of 5 rounds of annual MDA (total dose, 30 mg⁄kg) was shown to be as effective as 28 multi-dose MDA spread over 2 years (6 weekly plus 22 monthly treatments at 5 mg⁄kg; total dose, 140 mg⁄kg). Several additional studies carried out in Samoa in relation to the annual single-dose MDAs revealed that low density mf carriers, who have a very low mf count of 1-20⁄ml of venous blood, could not play a significant role in filariasis transmission.<br>From around 1990, studies on spaced low-dose DEC treatments and various types of combination chemotherapy with DEC and ivermectin increased. Albendazole, a well-known anti-intestinal helminths agent, was later added to the combination. The main findings of these studies with <I>W. bancrofti</I> are: (i) a single dose of DEC at 6 mg⁄kg reduced mean mf density by ca. 90% 1 year after treatment; (ii) the same dose could damage⁄kill adult worms; (iii) a single dose of ivermectin at ca. 400 μg⁄kg was more effective than DEC in reducing mf density during the first year and was similarly or less effective in the second year; (iv) ivermectin probably could not kill adult worms; (v) a single combined dose of albendazole (400 mg) and DEC (6 mg⁄kg) was effective to reduce mf density by 85 to nearly 100% 12-24 months after treatment; and (vi) ivermectin or albendazole included in the combination chemotherapy produced “beyond-filariasis” benefits: clearance⁄reduction of intestinal helminths, and, additionally, in the case of ivermectin, skin-dwelling ectoparasites.<br>The Global Programme to Eliminate Lymphatic Filariasis (GPELF) started its worldwide activities in 2000, with the target of elimination by 2020. The basic strategy is to conduct annual single-dose MDAs for 4-6 years. In 2000-2007, a minimum of 570 million individuals were treated in 48 of 83 endemic countries. The drugs used are DEC 6 mg⁄kg plus albendazole 400 mg in most countries, or ivermectin 200-400 μg⁄kg plus albendazole 400 mg particularly in onchocerciasis endemic countries in Africa. (MDAs with DEC alone had been used in India.)

Cost of mass drug administration for filiriasis elimination in the province of Sorsogon, Philippines

OBJECTIVE: Elimination eforts for lymphatic flariasis are underway in the Philippines using mass drug administration (MDA) of diethylcarbamazine and albendazole as one of the main strategies. This cost analysis was done to determine the MDA implementation cost and provide useful information to the control programme on how to best utilize limited resources. METHODS: This cost analysis study was conducted in the province of Sorsogon, Philippines in 2004. The study was done from a program perspective. Cost data for 2003 was obtained retrospectively via key informant interviews and records review using a standardized guide from a multi-country cost analysis study of flariasis elimination programs. Cost fgures were classifed as either economic or fnancial costs and expressed in real terms using 2002 as base year. Sensitivity analysis was likewise performed. RESULTS: The total economic cost and cost per person treated with MDA were estimated at US$223,549.55 (Php12,116,385.48) and US$0.40, respectively. The fnancial costs were less than half of the economic costs. The main cost driver was drug distribution. The highest economic and fnancial costs were incurred at the national (54.5%) and municipal (74.4%) levels, respectively. High variation in costs of MDA activities was observed. CONCLUSION: This cost analysis provides reasonable estimates which may be used to assist government and other stakeholders in program planning and resource generation for flariasis elimination programs in endemic areas.

Successful Control of Lymphatic Filariasis in the Republic of Korea

A successful experience of lymphatic filariasis control in the Republic of Korea is briefly reviewed. Filariasis in the Republic of Korea was exclusively caused by infection with Brugia malayi. Over the past several decades from the 1950s to 2006, many investigators exerted their efforts to detection, treatment, and follow-up of filariasis patients in endemic areas, and to control filariasis. Mass, combined with selective, treatments with diethylcarbamazine to microfilaria positive persons had been made them free from microfilaremia and contributed to significant decrease of the microfilarial density in previously endemic areas. Significant decrease of microfilaria positive cases in an area influenced eventually to the endemicity of filariasis in the relevant locality. Together with remarkable economic growth followed by improvement of environmental and personal hygiene and living standards, the factors stated above have contributed to blocking the transmission cycle of B. malayi and led to disappearance of this mosquito-borne ancient disease in the Republic of Korea.

Wuchereria bancrofti Filariasis Control in Samoa before PacELF (Pacific Programme to Eliminate Lymphatic Filariasis)

<I>Background</I><br>Samoa was formerly highly endemic for Wuchereria bancrofti filariasis transmitted by Aedes mosquitoes. Previous control efforts including sporadic mass drug administration (MDA) campaigns have reduced the prevalence to low levels but have not succeeded in eliminating the disease. To effectively plan, model and evaluate the worldwide elimination effort, the Global Programme to Eliminate Lymphatic Filariasis (GPFLF) needs data on filariasis epidemiology (including age and sex-specific prevalence and the density of microfilariae (Mf)) and estimates of the number of years of MDA required for elimination. The five-year nationwide MDA campaign carried out in Samoa before the start of the Pacific Programme to Eliminate Lymphatic Filariasis (PacELF) generated extensive data on these issues.<br><I>Methodology⁄Principal Findings</I><br>MDA campaigns were conducted in Samoa with diethylcarbamazine (DEC) in 1993 to 1995 and DEC plus ivermectin in 1996 to 1997 for all persons aged 2 years and above. Coverage of the MDA, as assessed from the campaign village register books, ranged from 62% to 97% depending on the year, and was over 80% in three out of five years. Village based surveys showed that prevalence of Mf declined from 4.3% in 1993 (N=10,256) to 1.1% in 1998 (N=4,054) (Pχ<SUP>2</SUP>=94.4, p<0.001). Males had a three- to five-fold higher prevalence than females, and this difference remained consistent over the five-year period. Transmission was still occurring over the period as shown by the occurrence of new infections in 3 children less than 5 years old out of 5,691 tested (five-year cumulative incidence of 0.53 per thousand children for the period 1993 to 1998). There was a statistically significant reduction in the geometric mean number of Mf per 60 μl in positive cases between 1993 (11.8) and 1998 (6.9) (t=2.61; p<0.01). The proportion of people with a high density of Mf - over 60 Mf per 60 μl (1000 per ml) - declined from to 19.4% to 4.0% (Pχ<SUP>2</SUP>=5.6, p=0.018).<I><br>Conclusions⁄Significance</I><br>Five years of sustained MDA with DEC (3 years) and DEC plus ivermectin (2 years) reduced the prevalence of Mf of <I>W.bancrofti</I> in Samoa by 74%. Density of Mf in infected individuals was also significantly reduced. Males had a three to five-fold higher prevalence than women. New infections in children less than five years old still occurred at a low level, suggesting that transmission was not completely interrupted. These findings helped to prepare a sound monitoring and evaluation plan for PacELF.

Dietilcarbamazina no tratamento da filariose bancroftiana / Diethylcarbamazine in the treatment of Bancroft's filariasis

Os autores realizaram uma ampla revisão sobre o tratamento da filariose bancroftiana com a droga dietilcarbamazina. Os aspectos interessantes sobre o histórico de sua descoberta e os conceitos básicos de sua farmacologia foram relatados de forma resumida. Ênfase especial, por outro lado, foi dada às especulações feitas pelos diversos autores sobre os achados intrigantes descritos na literatura. Foram trazidos os novos avanços sobre o conhecimento da doença, como por exemplo, a visualização pela ultra-sonografia do verme vivo de Wuchereria bancrofti, no seu hospedeiro natural, o homem. Isso possibilitou a compreensão de muitos dos achados aparentemente paradoxais encontrados na literatura sobre o tratamento da infeção com a DEC. Assim, devido à inexistência de uma droga sucessora que reunisse efeitos micro e macrofilaricidas ideais e aos novos conhecimentos sobre a bancroftose e sobre a própria dietilcarbamazina, foi-lhe conferido um novo realce. Esses aspectos a colocaram numa posição de destaque no cenário da infecção, à época do seu quase cinqüentenário de existência.

The authors presented a detailed review about the treatment of bancroftian filariasis with diethylcarbamazine. The interesting aspects about the drug discovery and the basic concepts about its pharmacology were reported in a summarised form. On the other hand, emphasis was made about the speculation done by several authors about the intriguing findings regarding its efficacy reported in the literature. Latter, it was brought the new advances about the disease, as for example, the visualization by ultrasound of living Wuchereria bancrofti adult worm on its natural host--the human being. This made possible the comprehension of several paradoxical issues reported, focusing the treatment of infection using diethylcarbamazine. So far, because of the lack of ideal drug with micro and macrofilaricidal properties, together with the new understand about the disease and the new parameters for monitoring the efficacy of the drug, diethylcarbamazine has back its importance conquered at the begin of its discovery, almost fifth years ago.

The inhibitory effects of diethylcarbamazine citrate on hypoxic pulmonary vasoconstriction in dogs / 中国病理生理杂志

The effects of diethylcarbamazine citrate (DEC), a lipooxygenase inhibitor, on hypoxic pulmonary vasoconstriction (HPV) in dogs were studied, The results showed that HPV was significantly inhibited after the intravenous administration of DEC, and that the inhibitory effect of DEC on HPV had seemingly no association with the decrease of systemic blood pressure and depression of cardiac function induced by DEC. It is suggested that leukotrienes play a role of mediator in HPV in dogs.