Browsing by Author "Sheikh, Zara"

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A review on nanoparticles based drug delivery in cancer treatment: advantages & challenges
(BRAC University, 2022-06) Nahar, Kamrun; Sheikh, Zara
Nanoparticles have unique physicochemical and biological properties that make them one of the most promising candidate for targeted cancer therapy. Nanoparticle-based drug delivery has a number of advantages over conventional drug delivery methods, including smaller particle size, enhanced stability and biocompatibility with enhanced permeability and retention effect and specific targeting to the tumor sites enabling selective killing of cancer cells without affecting the healthy cells. Owing to the beneficial properties of nanoparticles, they are increasingly being used to target cancer cells using active targeting and passive targeting mechanisms for both diagnostic and therapeutic purpose of various types of cancer treatment. The present review focuses on the different types of nanoparticles used as a targeted drug delivery system for cancer treatment, highlighting their potential advantages and the challenges associated with the application of these nanoparticles based drug delivery systems with a direction towards future cancer research.
Barriers to oral and inhaled drug delivery: a review
(BRAC University, 2022-08) Kamal, Farhana; Sheikh, Zara
Oral and pulmonary routes of drug administration are the two most common modes to deliver drugs to patients owing to their non-invasive nature. Among the two, the oral route is still the most preferred one due to a number of advantages such as ease of administration without requiring any assistance that offers enhanced patient compliance and cost-effectiveness. Several factors affect absorption orally delivered drugs including drug solubility, permeability across the mucosa, and stable position in the gastrointestinal tract environment. It is fundamental to understand the physicochemical, biochemical, metabolic and biological barriers which limit the overall bioavailability of therapeutic agents to address the problems associated with decreased oral absorption and bioavailability. Pulmonary route of drug administration holds the potential to overcome these problems of reduced absorption associated with oral drug delivery. However, pulmonary drug delivery is also negatively affected by mechanical, chemical, immunological barriers along with behavioral barriers linked with use of inhaler devices and poor patient adherence. To this end, the present review discusses the barriers associated with oral and pulmonary drug delivery, along with highlights of the advantages and disadvantages of both routes of drug administration with future perspectives.
Central nervous system depressant, analgesic and antidiarrheal effects of the seed extracts of Dimocarpus longan lour in rats
(© 2014 Tropical Journal of Pharmaceutical Research) Ripa, Farhana Alam; Ibn Morshed, Mahmud Tareq; Afsana-Al-Sharmin; Papon, Shahed Bulbul; Islam, Md Rafiqul; Sheikh, Zara
Purpose: To assess the central nervous system (CNS) depressant, analgesic and antidiarrheal activities of the dried seed crude extracts of Dimocarpus longan Lour in rodents. Methods: Selected pharmacological effects of the ethanol (ENLS), petroleum ether (PELS), chloroform (CHLS) and ethyl acetate (EALS) extracts of D. longan fruit seeds were investigated. CNS depressant activity was evaluated by open field and hole cross tests; analgesic activity by acetic acid-induced writhing test and formalin-induced licking test; and anti-diarrheal activity was assessed in castor oil and magnesium-induced diarrhea rat model. The extracts were given orally in a rat model at doses of 200 and 300 mg/kg body weight. Normal saline served as control in all experiment. In CNS depressant test, diazepam (1 mg/kg) was used as reference drug while indomethacin (10 mg/kg) and loperamide(2 mg/kg) were used as standard drugs in analgesic and antidiarrheal tests, respectively. Results: In hole cross method, EALS showed the most effective depressant effect, viz, 1.17±0.17 for 200 mg/kg dose and 0.83±0.31 number of movements for 300 mg/kg dose after 120 min (p < 0.01), whereas in the open field test, all the extracts exhibited significant (p < 0.01) depressant effect in relation to positive control, diazepam. In acetic acid-induced pain test, PELS gave the lowest number of writhing (2.83±0.307) and the highest inhibition (88.45 %, 300 mg/kg dose) which was statistically significant. All the extracts also significantly (p < 0.01) suppressed licking activity in both phases of the formalin-induced licking test, in contrast to indomethacin. In the antidiarrheal tests, diarrheal suppression was highest at 300 mg/kg dose for all the extracts, compared with loperamide in both castor oil and magnesium sulphate induced diarrhea model. Conclusion: The extracts of Dimocarpus longan tested demonstrated significant CNS depressant, analgesic and antidiarrheal activities in a rodent model.
Central nervous system depressant, analgesic and antidiarrheal effects of the seed extracts of Dimocarpus longan lour in rats
(© 2014 Tropical Journal of Pharmaceutical Research) Ripa, Farhana Alam; Ibn Morshed, Mahmud Tareq; Afsana-Al-Sharmin; Papon, Shahed Bulbul; Islam, Md Rafiqul; Sheikh, Zara
Purpose: To assess the central nervous system (CNS) depressant, analgesic and antidiarrheal activities of the dried seed crude extracts of Dimocarpus longan Lour in rodents. Methods: Selected pharmacological effects of the ethanol (ENLS), petroleum ether (PELS), chloroform (CHLS) and ethyl acetate (EALS) extracts of D. longan fruit seeds were investigated. CNS depressant activity was evaluated by open field and hole cross tests; analgesic activity by acetic acid-induced writhing test and formalin-induced licking test; and anti-diarrheal activity was assessed in castor oil and magnesium-induced diarrhea rat model. The extracts were given orally in a rat model at doses of 200 and 300 mg/kg body weight. Normal saline served as control in all experiment. In CNS depressant test, diazepam (1 mg/kg) was used as reference drug while indomethacin (10 mg/kg) and loperamide(2 mg/kg) were used as standard drugs in analgesic and antidiarrheal tests, respectively. Results: In hole cross method, EALS showed the most effective depressant effect, viz, 1.17±0.17 for 200 mg/kg dose and 0.83±0.31 number of movements for 300 mg/kg dose after 120 min (p < 0.01), whereas in the open field test, all the extracts exhibited significant (p < 0.01) depressant effect in relation to positive control, diazepam. In acetic acid-induced pain test, PELS gave the lowest number of writhing (2.83±0.307) and the highest inhibition (88.45 %, 300 mg/kg dose) which was statistically significant. All the extracts also significantly (p < 0.01) suppressed licking activity in both phases of the formalin-induced licking test, in contrast to indomethacin. In the antidiarrheal tests, diarrheal suppression was highest at 300 mg/kg dose for all the extracts, compared with loperamide in both castor oil and magnesium sulphate induced diarrhea model. Conclusion: The extracts of Dimocarpus longan tested demonstrated significant CNS depressant, analgesic and antidiarrheal activities in a rodent model.
Central nervous system depressant, analgesic and antidiarrheal effects of the seed extracts of Dimocarpus longan lour in rats
(© 2014 Tropical Journal of Pharmaceutical Research) Ripa, Farhana Alam; Ibn Morshed, Mahmud Tareq; Afsana-Al-Sharmin; Papon, Shahed Bulbul; Islam, Md Rafiqul; Sheikh, Zara
Purpose: To assess the central nervous system (CNS) depressant, analgesic and antidiarrheal activities of the dried seed crude extracts of Dimocarpus longan Lour in rodents. Methods: Selected pharmacological effects of the ethanol (ENLS), petroleum ether (PELS), chloroform (CHLS) and ethyl acetate (EALS) extracts of D. longan fruit seeds were investigated. CNS depressant activity was evaluated by open field and hole cross tests; analgesic activity by acetic acid-induced writhing test and formalin-induced licking test; and anti-diarrheal activity was assessed in castor oil and magnesium-induced diarrhea rat model. The extracts were given orally in a rat model at doses of 200 and 300 mg/kg body weight. Normal saline served as control in all experiment. In CNS depressant test, diazepam (1 mg/kg) was used as reference drug while indomethacin (10 mg/kg) and loperamide(2 mg/kg) were used as standard drugs in analgesic and antidiarrheal tests, respectively. Results: In hole cross method, EALS showed the most effective depressant effect, viz, 1.17±0.17 for 200 mg/kg dose and 0.83±0.31 number of movements for 300 mg/kg dose after 120 min (p < 0.01), whereas in the open field test, all the extracts exhibited significant (p < 0.01) depressant effect in relation to positive control, diazepam. In acetic acid-induced pain test, PELS gave the lowest number of writhing (2.83±0.307) and the highest inhibition (88.45 %, 300 mg/kg dose) which was statistically significant. All the extracts also significantly (p < 0.01) suppressed licking activity in both phases of the formalin-induced licking test, in contrast to indomethacin. In the antidiarrheal tests, diarrheal suppression was highest at 300 mg/kg dose for all the extracts, compared with loperamide in both castor oil and magnesium sulphate induced diarrhea model. Conclusion: The extracts of Dimocarpus longan tested demonstrated significant CNS depressant, analgesic and antidiarrheal activities in a rodent model.
Central nervous system depressant, analgesic and antidiarrheal effects of the seed extracts of Dimocarpus longan lour in rats
(© 2014 Tropical Journal of Pharmaceutical Research) Ripa, Farhana Alam; Ibn Morshed, Mahmud Tareq; Afsana-Al-Sharmin; Papon, Shahed Bulbul; Islam, Md Rafiqul; Sheikh, Zara
Purpose: To assess the central nervous system (CNS) depressant, analgesic and antidiarrheal activities of the dried seed crude extracts of Dimocarpus longan Lour in rodents. Methods: Selected pharmacological effects of the ethanol (ENLS), petroleum ether (PELS), chloroform (CHLS) and ethyl acetate (EALS) extracts of D. longan fruit seeds were investigated. CNS depressant activity was evaluated by open field and hole cross tests; analgesic activity by acetic acid-induced writhing test and formalin-induced licking test; and anti-diarrheal activity was assessed in castor oil and magnesium-induced diarrhea rat model. The extracts were given orally in a rat model at doses of 200 and 300 mg/kg body weight. Normal saline served as control in all experiment. In CNS depressant test, diazepam (1 mg/kg) was used as reference drug while indomethacin (10 mg/kg) and loperamide(2 mg/kg) were used as standard drugs in analgesic and antidiarrheal tests, respectively. Results: In hole cross method, EALS showed the most effective depressant effect, viz, 1.17±0.17 for 200 mg/kg dose and 0.83±0.31 number of movements for 300 mg/kg dose after 120 min (p < 0.01), whereas in the open field test, all the extracts exhibited significant (p < 0.01) depressant effect in relation to positive control, diazepam. In acetic acid-induced pain test, PELS gave the lowest number of writhing (2.83±0.307) and the highest inhibition (88.45 %, 300 mg/kg dose) which was statistically significant. All the extracts also significantly (p < 0.01) suppressed licking activity in both phases of the formalin-induced licking test, in contrast to indomethacin. In the antidiarrheal tests, diarrheal suppression was highest at 300 mg/kg dose for all the extracts, compared with loperamide in both castor oil and magnesium sulphate induced diarrhea model. Conclusion: The extracts of Dimocarpus longan tested demonstrated significant CNS depressant, analgesic and antidiarrheal activities in a rodent model.
Characterization of phytoconstituents and potential bioactivity of Annona reticulata L. leaf extract
(© 2016 Journal of Pharmacognosy and Phytochemistry, 2016) Shahriar, Mohammad; Khair, Nishat Zareen; Sheikh, Zara; Chowdhury, Sayeeda Fahmee; Kamruzzaman, Md.; Bakhtiar, Md. Shawkatul Islam; Chisty, Sharmin Jahan
Annona reticulata (Annonaceae) is known as atafol in Bangla and custard apple in English is an important medicinal plant. It has been used traditionally in diarrhea, dysentery, cold, as abortifacient, insecticidal drug etc. In this present study, the leaf extracts of Annona reticulata were subjected to evaluation of the thrombolytic activity was assessed by using human erythrocyte and the results were compared with standard streptokinase (SK). The chloroform extract showed 36.82% clot lysis as compared to 93.79% clot lysis produced by standard streptokinase. The leaf extracts of Annona reticulata were subjected to evaluation of the membrane stabilizing activity by using human erythrocyte and the results were compared with standard anti-inflammatory drug, acetyl salicylic acid (ASA). In vitro membrane stabilizing activity for hypotonic solution induced haemolysis, the chloroform extract inhibited 75.15% haemolysis of RBCs as compared to 72.99% produced by acetyl salicylic acid (ASA) and during heat induced condition different organic soluble materials of Annona reticulata demonstrated methanol, ethanol and chloroform extract showed 68.81%, 72.06% and 78.17% inhibition of RBC hemolysis respectively whereas standard acetylsalicylic acid showed 70.87% inhibition of RBC haemolysis.
Characterization of phytoconstituents and potential bioactivity of Annona reticulata L. leaf extract
(© 2016 Journal of Pharmacognosy and Phytochemistry, 2016) Shahriar, Mohammad; Khair, Nishat Zareen; Sheikh, Zara; Chowdhury, Sayeeda Fahmee; Kamruzzaman, Md.; Bakhtiar, Md. Shawkatul Islam; Chisty, Sharmin Jahan
Annona reticulata (Annonaceae) is known as atafol in Bangla and custard apple in English is an important medicinal plant. It has been used traditionally in diarrhea, dysentery, cold, as abortifacient, insecticidal drug etc. In this present study, the leaf extracts of Annona reticulata were subjected to evaluation of the thrombolytic activity was assessed by using human erythrocyte and the results were compared with standard streptokinase (SK). The chloroform extract showed 36.82% clot lysis as compared to 93.79% clot lysis produced by standard streptokinase. The leaf extracts of Annona reticulata were subjected to evaluation of the membrane stabilizing activity by using human erythrocyte and the results were compared with standard anti-inflammatory drug, acetyl salicylic acid (ASA). In vitro membrane stabilizing activity for hypotonic solution induced haemolysis, the chloroform extract inhibited 75.15% haemolysis of RBCs as compared to 72.99% produced by acetyl salicylic acid (ASA) and during heat induced condition different organic soluble materials of Annona reticulata demonstrated methanol, ethanol and chloroform extract showed 68.81%, 72.06% and 78.17% inhibition of RBC hemolysis respectively whereas standard acetylsalicylic acid showed 70.87% inhibition of RBC haemolysis.
Comparative study of quality control parameters of different brands of oral montelikast tablets available in Bangladesh
(BRAC University, 2015-03) Sarkar, Chandan; Sheikh, Zara
Quality control of pharmaceutical product emphasizes on various testing of the product which include both in-process and finished product quality control tests that are conducted prior to release of the drug in the market. In the present study the quality control parameters of ten different brands of Montelukast tablets available in Bangladesh were evaluated and compared to assess the quality of the tablets. The samples of the tablets were taken from five leading pharmaceutical companies of Bangladesh represented as A to E respectively, three medium ranked companies designated as F, G, H and two low ranked companies denoted as I and J respectively. Quality control tests such as weight variation, friability, hardness as well as disintegration tests were performed. In vitro dissolution study was carried out and analyzed by HPLC to determine the percentage release of drug after 30 minutes which may reflect in vivo performance of the drug. The weight variation results show that there was hardly any variation among the leading pharmaceutical companies (value ranging 0.17±0.01 gm to 0.2±0.01 gm) except for company B (0.35±0.01 gm) and the middle and lower ranked company showed slightly higher results. The tablets of all the ten companies showed acceptable values of hardness except for one low-ranked company J with a high value of 16.57±1.4 kg/cm2. There is a marginal difference in the result of the friability test of the all the ten companies (all values less than 1% according to BP specification), signifying that the Montelukast tablets produced by the different companies of Bangladesh have sufficient mechanical strength to withstand the pressure due to processing, storage and shipment. Disintegration times of the tablets of leading companies were found to be within 3 minutes indicating a very good result except for company A (7.40±0.9 minutes). Company F and company I showed the highest disintegration times (9.4±1.17 minutes and 9.8±3.6 minutes respectively). Consequently, the percentage release of drug for company A, company F and company I are less compared to other companies as shown by the dissolution study. Nevertheless, all the companies showed greater than 90% dissolution of drug after 30 minutes, thus complying with the specifications of British Pharmacopeia and US FDA guidelines for INN drugs. Hence, it can be concluded that Montelukast tablets produced by the pharmaceutical companies in Bangladesh are of consistent quality with very little variation among them and complies with the specifications of British Pharmacopeia.
Formulation and evaluation of acetaminophen suspension using fenugreek seeds as a natural suspending agent
(BRAC Univeristy, 2017-10) Khan, Ahmed Tareque; Sheikh, Zara
A great number of pharmaceutical excipients, both natural and synthetic, are available to meet the demands of the rapid development of the pharmaceutical industry. Nowadays, naturally derived excipients are preferred over synthetic excipients owing to their greater availability in nature, biocompatibility, biodegradability, non-toxicity, environment friendliness and cost-effectiveness. A good example of a natural source of excipient is Trigonella foenum graceum (Family: Leguminosae) seeds, also known as fenugreek seeds, which contains a high percentage of mucilage and forms viscous tacky mass that swells up when exposed to fluids and thus can be used as a suspending agent in pharmaceutical suspensions. The aim of the present study was to utilize fenugreek mucilage as a natural suspending agent by formulating and evaluating a suspension containing acetaminophen as the active pharmaceutical ingredient and incorporating fenugreek mucilage as the suspending agent. Five formulations (FS1 – FS5) each containing varying proportions of Trigonella foenum graceum mucilage, were prepared. The suspensions were subjected to evaluation by studying different parameters like pH, sedimentation volume, degree of flocculation, viscosity, redispersibility, flow rate, effect of temperature on viscosity and finally the rate of release of drug within twenty minutes. pH of all the formulations were found to be similar (approximately 7.8). The sedimentation volume did not change significantly over a period of 45 days indicating higher degree of flocculation and good stability of the suspensions. The suspensions were easily redispersible after shaking only twice even after 45 days and the flow rate of the suspensions did not differ much suggesting that suspensions with 2 gm of mucilage (FS4) can be used instead of FS3 (with 1.5 gm of mucilage) as it gives a higher degree of flocculation. The dissolution results of the suspensions were found to be satisfactory since on an average 65-70% of the drug was released within 20 minutes, thus complying with USP specifications. Even though all the formulations gave good results, it can be concluded that FS4 formulation is the optimum formulation with greater flocculation, good flow rate and easily redispersibility characteristics along with a good percentage release of drug within twenty minutes. These formulations can be compared with the market preparations for further evaluation.
Formulation and in vitro characterization of quercetin loaded solid lipid nanoparticles
(BRAC University, 2026-04) Rafsan, Rubayet; Hassan, Md. Mohiyminul; Mim, Jafrin Akter; Sohan, Md Sabbir Hosen; Sheikh, Zara
Quercetin is a common bioflavonoid with various potent therapeutic effects such as antioxidant anti-inflammatory and anticancer activity. However, the use of quercetin is limited owing to its low water solubility, limiting its oral bioavailability and in vivo beneficial functions. To enhance the bioavailability of quercetin, solid lipid nanoparticles of the quercetin were developed using the ultra-speed homogenization technique. Stearic acid has been used in the formulation as a solidlipid matrix and Tween-80 as a surfactant, comprising the aqueous part of the formulation. 16 different types of formulations (labelled as F1-F16) were prepared and optimized by varying the amount of stearic acid, Tween 80 and rotational speeds of the homogenizer. Among the 16 formulations, F5 formulation (composition: 25 mg of quercetin drug, 0.5 gm of stearic acid, 2% of Tween 80) and was found to be the optimum formulation with the highest encapsulation efficiency of 80% and further displaying a sustained release profile following a 2-hour dissolution study. The present study suggests that high-speed homogenization technique is a suitable method to develop solid-lipid nanoparticles of Quercetin with high entrapment efficiency. Further work is required to determine the efficacy of the formulation in terms of particle size, zeta potential, release profile, morphology using scanning electron microscopy, in vitro antioxidant study, antiinflammatory study, and bioequivalence study in animal models.
Hyperthyroidism: an overview of the disease and current treatment approach
(BRAC University, 2026-04) Ena, Israt Jahan; Sheikh, Zara
Hyperthyroidism is a condition where the thyroid gland produces excessive amounts of thyroid hormone thyroxine and triiodothyronine, affecting approximately 0.2%–2.5% of the global adult population, with rates generally higher in iodine-sufficient areas and more prevalent in women. Hyperthyroidism prevalence in Bangladesh is generally lower than hypothyroidism, with studies indicating rates of approximately 0.86%-1.04% for overt hyperthyroidism and around 0.65%- 1.73% for subclinical hyperthyroidism. The most common type is Graves’ disease (GD), toxic multinodular goiter and toxic adenoma. Hyperthyroidism impacts many different systems of the body including the integument, musculoskeletal, immune, ophthalmic, reproductive, gastrointestinal and cardiovascular systems. Management options for hyperthyroidism include anti-thyroid medications, radioactive iodine, and surgery. Anti-thyroid medications are often used temporarily to treat thyrotoxicosis in preparation for more definitive treatment with radioactive iodine or surgery. The present review provides an overview of hyperthyroidism disease, epidemiology of the disease, causes of hyperthyroidism, highlighting the key considerations in diagnosis and current treatment of hyperthyroidism along with providing future directions for research and improved management of the disease.
Hypothyroidism: an overview of the disease and current treatment approach
(BRAC University, 2026-02) Afrin, Sadia; Sheikh, Zara
Hypothyroidism (underactive thyroid) is a condition where the thyroid gland does not produce enough thyroid hormones to meet the body’s needs. As these hormones regulate how the body uses energy (metabolism), their deficiency causes many body functions to slow down. Common causes include Hashimoto’s disease (autoimmune attack), iodine deficiency, or post-treatment effects. Symptoms develop slowly, including fatigue, cold intolerance, weight gain, constipation, dry skin/hair, hoarse voice, depression, and memory issues. Levothyroxine monotherapy is the standard treatment for hypothyroidism. Nonetheless, numerous unclear inquiries remain about patients who are biochemically stable yet dissatisfied with their therapy results. The present review is to give an overview of hypothyroidism disease, epidemiology of the disease, causes of hypothyroidism, highlighting the key considerations in diagnosis and current treatment of hypothyroidism along with providing future directions for research and improve management of the disease. Future research should investigate whether alternate regimens could offer a solution for a particular group of people with remaining symptoms. Investigation of the efficacy of new formulations (e.g., slow-release liothyronine) or increased administration frequency of levothyroxine-liothyronine combination therapy (e.g., tri-daily liothyronine) in alleviating patient symptoms, alongside the identification of patient subgroups that may benefit from alternatives to levothyroxine monotherapy (e.g., through the identification of additional genetic polymorphisms that could elucidate the individual thyroid set-point) could provide a new dimension to hypothyroidism management.
Impact of cadmium exposure on human health with a focus on Bangladesh
(© 2014 European Journal of Toxicological Sciences, 2014-03) Kabir, Eva Rahman; Sheikh, Zara; Khan, Tanisha Tabassum Sayka
The environment in which we claim to “live” in has become a huge reservoir of toxic metals. Human health is under constant risk of deterioration due to increasing chronic exposure of such metals that adversely affect the quality of life of people. The deterioration of human health due to exposure to heavy metals has become a major issue of concern worldwide. Although adverse health effects caused by heavy metals have been known for a long time, exposure to heavy metals continues, and is even increasing in some parts of the world, particularly in less developed countries, even though emissions have declined in most developed countries over the last 100 years. One such heavy metal with a high toxicity found in the earth’s crust, associated with zinc, lead and copper ores is cadmium. Exposure to cadmium has long been recognized as a health hazard, both in industry and in general populations with high exposure. However, cadmium is toxic at very low exposure levels and has acute and chronic effects on health and environment which is thus the cause of great concern. The parts of body that are potentially affected from exposures to cadmium mainly involve the kidney, liver, lung, heart and bone. If one is exposed to cadmium or cadmium compounds, a number of factors will determine whether or not the person will be affected. These factors include not only dose and duration of contact, how he/she comes in contact with it but parameters such as age, sex, diet, family traits, lifestyle, and state of health also tend to contribute to determine the extent of exposure (ATSDR, 2012). The objective of this paper is to review available information on possible toxicities of cadmium on human health. Our aim in this study was to identify the possible impacts of cadmium on human health, with the ultimate goal of proposing the rationale for future quantitative research of cadmium in Bangladesh
Impact of cadmium exposure on human health with a focus on Bangladesh
(© 2014 European Journal of Toxicological Sciences, 2014-03) Kabir, Eva Rahman; Sheikh, Zara; Khan, Tanisha Tabassum Sayka
The environment in which we claim to “live” in has become a huge reservoir of toxic metals. Human health is under constant risk of deterioration due to increasing chronic exposure of such metals that adversely affect the quality of life of people. The deterioration of human health due to exposure to heavy metals has become a major issue of concern worldwide. Although adverse health effects caused by heavy metals have been known for a long time, exposure to heavy metals continues, and is even increasing in some parts of the world, particularly in less developed countries, even though emissions have declined in most developed countries over the last 100 years. One such heavy metal with a high toxicity found in the earth’s crust, associated with zinc, lead and copper ores is cadmium. Exposure to cadmium has long been recognized as a health hazard, both in industry and in general populations with high exposure. However, cadmium is toxic at very low exposure levels and has acute and chronic effects on health and environment which is thus the cause of great concern. The parts of body that are potentially affected from exposures to cadmium mainly involve the kidney, liver, lung, heart and bone. If one is exposed to cadmium or cadmium compounds, a number of factors will determine whether or not the person will be affected. These factors include not only dose and duration of contact, how he/she comes in contact with it but parameters such as age, sex, diet, family traits, lifestyle, and state of health also tend to contribute to determine the extent of exposure (ATSDR, 2012). The objective of this paper is to review available information on possible toxicities of cadmium on human health. Our aim in this study was to identify the possible impacts of cadmium on human health, with the ultimate goal of proposing the rationale for future quantitative research of cadmium in Bangladesh
Mucosal delivery of vaccines
(BRAC Univeristy, 2015-08) Karim, Rejaul; Sheikh, Zara
Vaccines are capable of inducing cellular and humoral immune responses which could provide prophylactic and therapeutic responses against various diseases such as those that are infectious in nature and other that are malignant in nature such as cancer. These responses can also be stimulated systemically and at the mucosal surfaces by activating the mucosal immune process. However most licensed vaccines are administered parenterally and fail to elicit protective mucosal immunity. Immunization by mucosal routes may be more effective at inducing protective immunity against mucosal pathogens at the site of entry. Different challenges are associated with different varieties of vaccines. The present review summarizes the various delivery strategies that can improve the mucosal delivery of the vaccines, the carrier systems and the adjuvants that can be used along with the vaccines to overcome these challenges and thereby enhance the mucosal vaccination. The usage of particulate delivery is an effective method that can be taken up to enhance mucosal vaccination. This is done by protecting the immunogenic material during the delivery, facilitating specific target oriented delivery system, and by allowing incorporation of various adjuvant materials. Efforts are focused on efficient delivery of vaccine antigens to mucosal sites that facilitate uptake by local antigen-presenting cells to generate protective mucosal immune response. Future issues regarding mucosal vaccine development have also been pointed out that includes targeting mucosal dendritic cells as an effective and safe strategy for inducing antigen-specific immunity as well as finding out new routes of mucosal immunization and antigen delivery systems along with novel mucosal adjuvants.
Optimizing oral drug delivery using lipid based formulations
(© 2014 International Research Journal of Pharmacy, 2014) Sheikh, Zara; Nabila, Morshed
A great challenge facing the pharmaceutical scientists is transforming the new pharmacologically active lipophilic compounds that are poorly water soluble into orally administered medications with sufficient bioavailability. Lipid-based drug delivery systems has shown a great potential in the oral delivery of poorly water-soluble drugs, primarily for lipophilic drugs, with several successfully marketed products. Oral lipid-based formulations comprises of a broad range of oils, surfactants, and co-solvents. This review provides a comprehensive summary of the development, characterization, and utilization of oral lipid- based formulations, from both physicochemical and biopharmaceutical perspectives. The properties of the various lipid excipients are discussed and the criteria for selection of excipients for lipid-based formulations are identified. Finally the future prospects of this technique have been addressed to expand the utility of lipid based drug delivery systems.
Phytochemical analysis, cytotoxic and in vitro antioxidant activity of erythrina variegate bark
(© 2015 European Journal of Medicinal Plants, 2015-11) Shahriar, Mohammad; Khair, Nishat Zareen; Sheikh, Zara; Chowdhury, Sayeeda Fahmee; Kamruzzaman, Md.; Bakhtiar, Md. Shawkatul Islam; Chisty, Sharmin Jahan; Narjish, Syeda Najah; Akhter, Rumana; Akter, Nahia
Aim:The objective of the present study was to investigate the phytochemical analysis, cytotoxic and antioxidant activities of the bark extracts of Erythrina variegate.Place and Duration of Study: The plant, E. variegate was collected from Botanical Garden, Mirpur, Dhaka and also from Curzon Hall, University of Dhaka, Bangladesh in June 2014 and then the sample was identified by the National Herbarium of Bangladesh, Mirpur, Dhaka (DACB; Accession Number- 36148). Methodology: Preliminary phytochemical screening was done for determining the nature of phytoconstituents. Brine shrimp lethality bioassay technique was done to study the cytotoxic properties. Aluminum chloride colorimetric method was applied for the determination of flavonoids and the total antioxidant ability was assessed by the phospho-molybdenum method. Results: Primary phytochemical analysis confirmed the presence of alkaloid, carbohydrate, glycosides and flavonoids. The extracts showed some toxicity to A. salina with LC50 values ranging from 1.41 to 3.66 μ g/ml which was compared with standard vincristine sulphate (VS, LC50 value 0.92 μg/ml). n-Hexane extract of E. variegate was found to contain highest amount of flavonoids (3.77±1.97 mg/gm; quercetin equivalent) and ethanol extract of E. variegate was found to have highest antioxidant acitivity (2.03±0.09 mg/gm ascorbic acid equivalent). Conclusion: It can be concluded that the plant extracts of E. variegate possess several antioxidant activities which justifies its use as folk medicine.
Phytochemical analysis, cytotoxic and in vitro antioxidant activity of erythrina variegate bark
(© 2015 European Journal of Medicinal Plants, 2015-11) Shahriar, Mohammad; Khair, Nishat Zareen; Sheikh, Zara; Chowdhury, Sayeeda Fahmee; Kamruzzaman, Md.; Bakhtiar, Md. Shawkatul Islam; Chisty, Sharmin Jahan; Narjish, Syeda Najah; Akhter, Rumana; Akter, Nahia
Aim:The objective of the present study was to investigate the phytochemical analysis, cytotoxic and antioxidant activities of the bark extracts of Erythrina variegate.Place and Duration of Study: The plant, E. variegate was collected from Botanical Garden, Mirpur, Dhaka and also from Curzon Hall, University of Dhaka, Bangladesh in June 2014 and then the sample was identified by the National Herbarium of Bangladesh, Mirpur, Dhaka (DACB; Accession Number- 36148). Methodology: Preliminary phytochemical screening was done for determining the nature of phytoconstituents. Brine shrimp lethality bioassay technique was done to study the cytotoxic properties. Aluminum chloride colorimetric method was applied for the determination of flavonoids and the total antioxidant ability was assessed by the phospho-molybdenum method. Results: Primary phytochemical analysis confirmed the presence of alkaloid, carbohydrate, glycosides and flavonoids. The extracts showed some toxicity to A. salina with LC50 values ranging from 1.41 to 3.66 μ g/ml which was compared with standard vincristine sulphate (VS, LC50 value 0.92 μg/ml). n-Hexane extract of E. variegate was found to contain highest amount of flavonoids (3.77±1.97 mg/gm; quercetin equivalent) and ethanol extract of E. variegate was found to have highest antioxidant acitivity (2.03±0.09 mg/gm ascorbic acid equivalent). Conclusion: It can be concluded that the plant extracts of E. variegate possess several antioxidant activities which justifies its use as folk medicine.
Phytochemical and hypoglycemic screening of seeds and peel of nephelium longan fruits
(© 2015 International Journal of Biochemistry, 2015-12) Ripa, Farhana; Dash, Pritesh Ranjan; Nesa, Mst. Luthfun; Sheikh, Zara
Phytotherapy is considered to be lowest lethal or has no side effects in contrast to current allopathic medicines. The intention of the present investigation was to assess the therapeutic efficacy of Nephelium longan extract in an animal model of diabetes. So in this research we have performed phytochemical screening of methanolic extracts of peel (MNLP)