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Fulltext Tracing contacts of TB patients in Malaysia: costs and practicality

Atif M, Sulaiman SA, Shafie AA, Ali I, Asif M

Springerplus, 2012;1:40.
PMID: 23961366 DOI: 10.1186/2193-1801-1-40

Tuberculin skin testing (TST) and chest X-ray are the conventional methods used for tracing suspected tuberculosis (TB) patients. The purpose of the study was to calculate the cost incurred by Penang General Hospital on performing one contact tracing procedure using an activity based costing approach. Contact tracing records (including the demographic profile of contacts and outcome of the contact tracing procedure) from March 2010 until February 2011 were retrospectively obtained from the TB contact tracing record book. The human resource cost was calculated by multiplying the mean time spent (in minutes) by employees doing a specific activity by their per-minute salaries. The costs of consumables, Purified Protein Derivative vials and clinical equipment were obtained from the procurement section of the Pharmacy and Radiology Departments. The cost of the building was calculated by multiplying the area of space used by the facility with the unit cost of the public building department. Straight-line deprecation with a discount rate of 3% was assumed for the calculation of equivalent annual costs for the building and machines. Out of 1024 contact tracing procedures, TST was positive (≥10 mm) in 38 suspects. However, chemoprophylaxis was started in none. Yield of contact tracing (active tuberculosis) was as low as 0.5%. The total unit cost of chest X-ray and TST was MYR 9.23 (2.90 USD) & MYR 11.80 (USD 3.70), respectively. The total cost incurred on a single contact tracing procedure was MYR 21.03 (USD 6.60). Our findings suggest that the yield of contact tracing was very low which may be attributed to an inappropriate prioritization process. TST may be replaced with more accurate and specific methods (interferon gamma release assay) in highly prioritized contacts; or TST-positive contacts should be administered 6H therapy (provided that the chest radiography excludes TB) in accordance with standard protocols. The unit cost of contact tracing can be significantly reduced if radiological examination is done only in TST or IRGA positive contacts.
Fulltext Cytokine expression profile of dengue patients at different phases of illness

Rathakrishnan A, Wang SM, Hu Y, Khan AM, Ponnampalavanar S, Lum LC, et al.

PLoS One, 2012;7(12):e52215.
PMID: 23284941 DOI: 10.1371/journal.pone.0052215

BACKGROUND: Dengue is an important medical problem, with symptoms ranging from mild dengue fever to severe forms of the disease, where vascular leakage leads to hypovolemic shock. Cytokines have been implicated to play a role in the progression of severe dengue disease; however, their profile in dengue patients and the synergy that leads to continued plasma leakage is not clearly understood. Herein, we investigated the cytokine kinetics and profiles of dengue patients at different phases of illness to further understand the role of cytokines in dengue disease.
METHODS AND FINDINGS: Circulating levels of 29 different types of cytokines were assessed by bead-based ELISA method in dengue patients at the 3 different phases of illness. The association between significant changes in the levels of cytokines and clinical parameters were analyzed. At the febrile phase, IP-10 was significant in dengue patients with and without warning signs. However, MIP-1β was found to be significant in only patients with warning signs at this phase. IP-10 was also significant in both with and without warning signs patients during defervescence. At this phase, MIP-1β and G-CSF were significant in patients without warning signs, whereas MCP-1 was noted to be elevated significantly in patients with warning signs. Significant correlations between the levels of VEGF, RANTES, IL-7, IL-12, PDGF and IL-5 with platelets; VEGF with lymphocytes and neutrophils; G-CSF and IP-10 with atypical lymphocytes and various other cytokines with the liver enzymes were observed in this study.
CONCLUSIONS: The cytokine profile patterns discovered between the different phases of illness indicate an essential role in dengue pathogenesis and with further studies may serve as predictive markers for progression to dengue with warning signs.
Fulltext Development and validation of RP-HPLC-UV method for the determination of Glipizide in human plasma

Atif M, Khalid SH, Onn Kit GL, Sulaiman SA, Asif M, Chandersekaran A

J Young Pharm, 2013 Mar;5(1):26-9.
PMID: 24023449 DOI: 10.1016/j.jyp.2013.01.005

A simple, sensitive and selective HPLC method with UV detection for determination of Glipizide in human plasma was developed. Liquid-liquid extraction method was used to extract the drug from the plasma samples. Chromatographic separation of Glipizide was achieved using C18 column (ZORBAX ODS 4.6 × 150 mm). The mobile phase was comprised of 0.01 M potassium dihydrogen phosphate and acetonitrile (65:35, v/v) adjusted to pH 4.25 with glacial acetic acid. The analysis was run at a flow rate of 1.5 mL/min with an injection volume was 20 μL. The detector was operated at 275 nm. The calibration curve was linear over a concentration range of 50-1600 ng/mL. Intra-day and inter-day precision and accuracy values were below 15%. The limit of quantification was 50 ng/mL and the mean recovery was above 98%. Freeze-thaw, short-term, long-term and post-preparative stability studies showed that Glipizide in plasma sample was stable. The method may be successfully applied to analyze the Glipizide concentration in plasma samples for bioavailability and bioequivalence studies.
Fulltext APBioNet-transforming bioinformatics in the Asia-Pacific region

Khan AM, Tan TW, Schönbach C, Ranganathan S

PLoS Comput Biol, 2013 Oct;9(10):e1003317.
PMID: 24204244 DOI: 10.1371/journal.pcbi.1003317
SF-36v2 norms and its' discriminative properties among healthy households of tuberculosis patients in Malaysia

Atif M, Sulaiman SA, Shafie AA, Asif M, Ahmad N

Qual Life Res, 2013 Oct;22(8):1955-64.
PMID: 23239084 DOI: 10.1007/s11136-012-0337-x

BACKGROUND: The aim of the study was to obtain norms of the SF-36v2 health survey and the association of summary component scores with socio-demographic variables in healthy households of tuberculosis (TB) patients.
DESIGN: All household members (18 years and above; healthy; literate) of registered tuberculosis patients who came for contact tracing during March 2010 to February 2011 at the respiratory clinic of Penang General Hospital were invited to complete the SF-36v2 health survey using the official translation of the questionnaire in Malay, Mandarin, Tamil and English. Scoring of the questionnaire was done using Quality Metric's QM Certified Scoring Software version 4. Multivariate analysis was conducted to uncover the predictors of physical and mental health.
RESULTS: A total of 649 eligible respondents were approached, while 525 agreed to participate in the study (response rate = 80.1 %). Out of consenting respondents, 46.5 % were male and only 5.3 % were over 75 years. Internal consistencies met the minimum criteria (α > 0.7). Reliability coefficients of the scales were always less than their own reliability coefficients. Mean physical component summary scale scores were equivalent to United States general population norms. However, there was a difference of more than three norm-based scoring points for mean mental component summary scores indicating poor mental health. A notable proportion of the respondents was at the risk of depression. Respondents aged 75 years and above (p = 0.001; OR 32.847), widow (p = 0.013; OR 2.599) and postgraduates (p < 0.001; OR 7.865) were predictors of poor physical health while unemployment (p = 0.033; OR 1.721) was the only predictor of poor mental health.
CONCLUSION: The SF-36v2 is a valid instrument to assess HRQoL among the households of TB patients. Study findings indicate the existence of poor mental health and risk of depression among family caregivers of TB patients. We therefore recommend that caregivers of TB patients to be offered intensive support and special attention to cope with these emotional problems.
Study site: Respiratory clinic, Hospital Pulau Pinang, Malaysia
Fulltext Dissecting the dynamics of HIV-1 protein sequence diversity

Hu Y, Tan PT, Tan TW, August JT, Khan AM

PLoS One, 2013;8(4):e59994.
PMID: 23593157 DOI: 10.1371/journal.pone.0059994

The rapid mutation of human immunodeficiency virus-type 1 (HIV-1) and the limited characterization of the composition and incidence of the variant population are major obstacles to the development of an effective HIV-1 vaccine. This issue was addressed by a comprehensive analysis of over 58,000 clade B HIV-1 protein sequences reported over at least 26 years. The sequences were aligned and the 2,874 overlapping nonamer amino acid positions of the viral proteome, each a possible core binding domain for human leukocyte antigen molecules and T-cell receptors, were quantitatively analyzed for four patterns of sequence motifs: (1) "index", the most prevalent sequence; (2) "major" variant, the most common variant sequence; (3) "minor" variants, multiple different sequences, each with an incidence less than that of the major variant; and (4) "unique" variants, each observed only once in the alignment. The collective incidence of the major, minor, and unique variants at each nonamer position represented the total variant population for the position. Positions with more than 50% total variants contained correspondingly reduced incidences of index and major variant sequences and increased minor and unique variants. Highly diverse positions, with 80 to 98% variant nonamer sequences, were present in each protein, including 5% of Gag, and 27% of Env and Nef, each. The multitude of different variant nonamer sequences (i.e. nonatypes; up to 68%) at the highly diverse positions, represented by the major, multiple minor, and multiple unique variants likely supported variants function both in immune escape and as altered peptide ligands with deleterious T-cell responses. The patterns of mutational change were consistent with the sequences of individual HXB2 and C1P viruses and can be considered applicable to all HIV-1 viruses. This characterization of HIV-1 protein mutation provides a foundation for the design of peptide-based vaccines and therapeutics.
Fulltext Resource utilization pattern and cost of tuberculosis treatment from the provider and patient perspectives in the state of Penang, Malaysia

Atif M, Sulaiman SA, Shafie AA, Asif M, Babar ZU

BMC Health Serv Res, 2014 Aug 19;14:353.
PMID: 25138659 DOI: 10.1186/1472-6963-14-353

BACKGROUND: Studies from both developed and developing countries have demonstrated a considerable fluctuation in the average cost of TB treatment. The objective of this study was to analyze the medical resource utilization among new smear positive pulmonary tuberculosis patients. We also estimated the cost of tuberculosis treatment from the provider and patient perspectives, and identified the significant cost driving factors.
METHODS: All new smear positive pulmonary tuberculosis patients who were registered at the chest clinic of the Penang General Hospital, between March 2010 and February 2011, were invited to participate in the study. Provider sector costs were estimated using bottom-up, micro-costing technique. For the calculation of costs from the patients' perspective, all eligible patients who agreed to participate in the study were interviewed after the intensive phase and subsequently at the end of the treatment by a trained nurse. PASW was used to analyze the data (Predictive Analysis SoftWare, version 19.0, Armonk, NY: IBM Corp.).
RESULTS: During the study period, 226 patients completed the treatment. However, complete costing data were available for 212 patients. The most highly utilized resources were chest X-ray followed by sputum smear examination. Only a smaller proportion of the patients were hospitalized. The average provider sector cost was MYR 992.34 (i.e., USD 325.35 per patient) whereby the average patient sector cost was MYR 1225.80 (i.e., USD 401.90 per patient). The average patient sector cost of our study population accounted for 5.7% of their annual family income. In multiple linear regression analysis, prolonged treatment duration (i.e., > 6 months) was the only predictor of higher provider sector costs whereby higher patient sector costs were determined by greater household income and persistent cough at the end of the intensive phase of the treatment.
CONCLUSION: In relation to average provider sector cost, our estimates are substantially higher than the budget allocated by the Ministry of Health for the treatment of a tuberculosis case in Malaysia. The expenses borne by the patients and their families on the treatment of the current episode of tuberculosis were not catastrophic for them.
Study site: Chest clinic, Hospital Pulau Pinang, Malaysia
Fulltext Resource Utilization Pattern And Cost Of Tuberculosis Treatment In Penang, Malaysia

Atif M, Sulaiman SA, Shafie AA, Asif M

Value Health, 2014 Nov;17(7):A725-6.
PMID: 27202579 DOI: 10.1016/j.jval.2014.08.051
Fulltext Diuretic activity of Boswellia serrata Roxb. oleo gum extract in albino rats

Asif M, Jabeen Q, Abdul-Majid AM, Atif M

Pak J Pharm Sci, 2014 Nov;27(6):1811-7.
PMID: 25362605

The aim of the study was to evaluate the effect of crude aqueous extract of Boswellia serrata Roxb. oleo gum on urinary electrolytes, pH and diuretic activity in normal albino rats. Moreover, acute toxicity of the gum extract was assessed using mice. Albino rats were divided into five groups. Control group received normal saline (10 mg/kg), reference group received furosemide (10 mg/kg) and test groups were given different doses of crude extract (10, 30 and 50 mg/kg) by intra-peritoneal route, respectively. The Graph Pad Prism was used for the statistical analysis and p < 0.05 was considered statistically significant. Significant diuretic, kaliuretic and natriuretic effects were observed in the treated groups in a dose dependent manner. Diuretic index showed good diuretic activity of the crude extract. Lipschitz values indicated that the crude extract, at the dose of 50 mg/kg, showed 44 % diuretic activity compared to the reference drug. No lethal effects were observed among albino mice even at the higher dose of 3000 mg/kg. It is concluded that aqueous extract of Boswellia serrata oleo gum, at the dose of 50 mg/kg showed significant effects on urinary volume and concentration of urinary electrolytes with no signs of toxicity.
Fulltext Treatment outcome of new smear positive pulmonary tuberculosis patients in Penang, Malaysia

Atif M, Sulaiman SA, Shafie AA, Ali I, Asif M, Babar ZU

BMC Infect Dis, 2014;14:399.
PMID: 25037452 DOI: 10.1186/1471-2334-14-399

According to the World Health Organization's recent report, in Malaysia, tuberculosis (TB) treatment success rate for new smear positive pulmonary tuberculosis (PTB) patients is still below the global success target of 85%. In this study, we evaluated TB treatment outcome among new smear positive PTB patients, and identified the predictors of unsuccessful treatment outcome and longer duration of treatment (i.e., > 6 months).
Fulltext STATdb: a specialised resource for the STATome

Patro CP, Khan AM, Tan TW, Fu XY

PLoS One, 2014;9(8):e104597.
PMID: 25157689 DOI: 10.1371/journal.pone.0104597

Signal transducers and activators of transcription (STAT) proteins are key signalling molecules in metazoans, implicated in various cellular processes. Increased research in the field has resulted in the accumulation of STAT sequence and structure data, which are scattered across various public databases, missing extensive functional annotations, and prone to effort redundancy because of the dearth of community sharing. Therefore, there is a need to integrate the existing sequence, structure and functional data into a central repository, one that is enriched with annotations and provides a platform for community contributions. Herein, we present STATdb (publicly available at http://statdb.bic.nus.edu.sg/), the first integrated resource for STAT sequences comprising 1540 records representing the known STATome, enriched with existing structural and functional information from various databases and literature and including manual annotations. STATdb provides advanced features for data visualization, analysis and prediction, and community contributions. A key feature is a meta-predictor to characterise STAT sequences based on a novel classification that integrates STAT domain architecture, lineage and function. A curation policy workflow has been devised for regulated and structured community contributions, with an update policy for the seamless integration of new data and annotations.
Fulltext Tuberculosis deaths: are we measuring accurately?

Atif M, Sulaiman SA, Shafie AA, Qamar Uz Zaman M, Asif M

J Pharm Policy Pract, 2014;7(1):16.
PMID: 25838918 DOI: 10.1186/2052-3211-7-16

Death among tuberculosis patients is one of the major reasons for non-attainment of 85% treatment success target set by World Health Organization. In this short paper, we evaluated whether the overall mortality rate in pulmonary tuberculosis is being affected by other comorbid conditions. All new smear positive pulmonary tuberculosis patients (N =336), who started their treatment at the chest clinic of the Penang General Hospital, between March 2010 and February 2011, were followed-up until December 2011. Tuberculosis treatment outcomes were reported according to six treatment outcome categories recommended by World Health Organization. The outcome category 'died' was defined as 'a patient who died due to tuberculosis or other cause during tuberculosis treatment'. Our findings showed that out of 336 smear positive pulmonary tuberculosis patients, 59 (17.6%) died during treatment (mortality rate = 1.003 cases per 1000 person-days of follow-up). Among the deceased patients, the mean age was 55.8 years (SD =16.17) and 49 were male. According to the mortality review forms, 29 deaths were tuberculosis-related, while the remaining 30 patients died due to reasons other than tuberculosis. Cerebrovascular accident (n =7), septicaemia shock (n =4) and acute coronary syndrome (n =4) were the most common non-tuberculosis related reasons for mortality in the patients. If the 30 patients, for whom tuberculosis was incidental to death, are excluded from the final cohort, the proportion of patients in the 'died' outcome category could be reduced to 9.5%. The treatment outcome criterion (i.e., died) set by World Health Organization has limitations. Therefore, it requires improvement for more objective evaluation of the performance of the National Tuberculosis Program.
Study site: Chest clinic, Hospital Pulau Pinang, Malaysia
Fulltext Impact of tuberculosis treatment on health-related quality of life of pulmonary tuberculosis patients: a follow-up study

Atif M, Sulaiman SA, Shafie AA, Asif M, Sarfraz MK, Low HC, et al.

Health Qual Life Outcomes, 2014;12:19.
PMID: 24528499 DOI: 10.1186/1477-7525-12-19

At present, much of the attention within tuberculosis (TB) management is spent on microbiological cure, and its impact on health-related quality of life (HRQoL) is either undervalued or seldom considered. The aim of this study was to evaluate the impact of TB treatment on HRQoL of new smear positive pulmonary tuberculosis (PTB) patients. Moreover, we also aimed to determine whether the selected socio-demographic and clinical variables were predictive of variability in the HRQoL scores over time.
Fulltext Recent updates in the treatment of neurodegenerative disorders using natural compounds

Rasool M, Malik A, Qureshi MS, Manan A, Pushparaj PN, Asif M, et al.

Evid Based Complement Alternat Med, 2014;2014:979730.
PMID: 24864161 DOI: 10.1155/2014/979730

Neurodegenerative diseases are characterized by protein aggregates and inflammation as well as oxidative stress in the central nervous system (CNS). Multiple biological processes are linked to neurodegenerative diseases such as depletion or insufficient synthesis of neurotransmitters, oxidative stress, abnormal ubiquitination. Furthermore, damaging of blood brain barrier (BBB) in the CNS also leads to various CNS-related diseases. Even though synthetic drugs are used for the management of Alzheimer's disease, Parkinson's disease, autism, and many other chronic illnesses, they are not without side effects. The attentions of researchers have been inclined towards the phytochemicals, many of which have minimal side effects. Phytochemicals are promising therapeutic agents because many phytochemicals have anti-inflammatory, antioxidative as well as anticholinesterase activities. Various drugs of either synthetic or natural origin applied in the treatment of brain disorders need to cross the BBB before they can be used. This paper covers various researches related to phytochemicals used in the management of neurodegenerative disorders.
Fulltext Hepatoprotective Effects of Silybum marianum (Silymarin) and Glycyrrhiza glabra (Glycyrrhizin) in Combination: A Possible Synergy

Rasool M, Iqbal J, Malik A, Ramzan HS, Qureshi MS, Asif M, et al.

Evid Based Complement Alternat Med, 2014;2014:641597.
PMID: 24795768 DOI: 10.1155/2014/641597

Oxidative stress, lipid peroxidation, and transaminase reactions are some of the mechanisms that can lead to liver dysfunction. A time-dependent study was designed to evaluate the ability of silymarin (SLN) and glycyrrhizin (GLN) in different dosage regimens to lessen oxidative stress in the rats with hepatic injury caused by the hepatotoxin carbon tetrachloride. Wistar male albino rats (n = 60) were randomly assigned to six groups. Group A served as a positive control while groups B, C, D, E, and F received a dose of CCl4 (50% solution of CCl4 in liquid paraffin, 2 mL/kg, intraperitoneally) twice a week to induce hepatic injury. Additionally, the animals received SLN and GLN in different doses for a period of six weeks. CCl4 was found to induce hepatic injury by significantly increasing serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and thiobarbituric acid reactive substances while decreasing total protein and the activities of reduced glutathione, superoxide dismutase, and catalase. Treatment with various doses of SLN and GLN significantly reduced ALT, AST, ALP, and TBARS levels and increased GSH, SOD, and CAT levels. Our findings indicated that SLN and GLN have hepatoprotective effects against oxidative stress of the liver.
Pyrolysis kinetics of raw and hydrothermally carbonized Karanj (Pongamia pinnata) fruit hulls via thermogravimetric analysis

Islam MA, Asif M, Hameed BH

Bioresour Technol, 2015 Mar;179:227-233.
PMID: 25545092 DOI: 10.1016/j.biortech.2014.11.115

The pyrolysis of karanj fruit hulls (KFH) and karanj fruit hull hydrothermal carbonization (KFH-HTC) hydrochar was thermogravimetrically investigated under a nitrogen environment at 5 °C/min, 10 °C/min, and 20 °C/min. The pyrolysis decomposition of KFH biomass was faster than that of KFH-HTC hydrochar because of the high volatility and fixed carbon of KFH biomass. Weight loss percentage was also affected by the heating rates. The kinetic data were evaluated with the Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa methods. The activation energy values obtained with these two methods were 61.06 and 68.53 kJ/mol for KFH biomass and 130.49 and 135.87 kJ/mol for KFH-HTC hydrochar, respectively. The analysis of kinetic process mechanisms was verified with the Coats-Redfern method. KFH-HTC hydrochar may play a potential role in transforming biomass to energy-rich feedstock for thermochemical applications because of its high heating value, high fixed carbon, and low ash and sulfur contents.
Fulltext African Trypanosome-Induced Blood-Brain Barrier Dysfunction under Shear Stress May Not Require ERK Activation

Sumpio BJ, Chitragari G, Moriguchi T, Shalaby S, Pappas-Brown V, Khan AM, et al.

Int. J. Angiol., 2015 Mar;24(1):41-6.
PMID: 27053915 DOI: 10.1055/s-0034-1370890

African trypanosomes are tsetse fly transmitted protozoan parasites responsible for human African trypanosomiasis, a disease characterized by a plethora of neurological symptoms and death. How the parasites under microvascular shear stress (SS) flow conditions in the brain cross the blood-brain barrier (BBB) is not known. In vitro studies using static models comprised of human brain microvascular endothelial cells (BMEC) show that BBB activation and crossing by trypanosomes requires the orchestration of parasite cysteine proteases and host calcium-mediated cell signaling. Here, we examine BMEC barrier function and the activation of extracellular signal-regulated kinase (ERK)1/2 and ERK5, mitogen-activated protein kinase family regulators of microvascular permeability, under static and laminar SS flow and in the context of trypanosome infection. Confluent human BMEC were cultured in electric cell-substrate impedance sensing (ECIS) and parallel-plate glass slide chambers. The human BMEC were exposed to 2 or 14 dyn/cm(2) SS in the presence or absence of trypanosomes. Real-time changes in transendothelial electrical resistance (TEER) were monitored and phosphorylation of ERK1/2 and ERK5 analyzed by immunoblot assay. After reaching confluence under static conditions human BMEC TEER was found to rapidly increase when exposed to 2 dyn/cm(2) SS, a condition that mimics SS in brain postcapillary venules. Addition of African trypanosomes caused a rapid drop in human BMEC TEER. Increasing SS to 14 dyn/cm(2), a condition mimicking SS in brain capillaries, led to a transient increase in TEER in both control and infected human BMEC. However, no differences in ERK1/2 and ERK5 activation were found under any condition tested. African trypanosomiasis alters BBB permeability under low shear conditions through an ERK1/2 and ERK5 independent pathway.
Adsorption of 2,4-dichlorophenoxyacetic acid by mesoporous activated carbon prepared from H3PO4-activated langsat empty fruit bunch

Njoku VO, Islam MA, Asif M, Hameed BH

J Environ Manage, 2015 May 1;154:138-44.
PMID: 25721981 DOI: 10.1016/j.jenvman.2015.02.002

The removal of toxic herbicide from wastewater is challenging due to the availability of suitable adsorbents. The Langsat empty fruit bunch is an agricultural waste and was used in this study as a cheap precursor to produce activated carbon for the adsorption of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) at different initial concentrations ranging from 50 to 400 mg/L. The produced Langsat empty fruit bunch activated carbon (LEFBAC) was mesoporous and had high surface area of 1065.65 m(2)/g with different active functional groups. The effect of shaking time, temperature and pH on 2,4-D removal were investigated using the batch technique. The adsorption capacity of 2,4-D by LEFBAC was decreased with increase in pH of solution whereas adsorption capacity increased with temperature. The adsorption data was well described by Langmuir isotherm followed by removal capacity of 261.2 mg/g at 30 °C. The results from this work showed that LEFBAC can be used as outstanding material for anionic herbicide uptake from wastewater.
Combustion kinetics of hydrochar produced from hydrothermal carbonisation of Karanj (Pongamia pinnata) fruit hulls via thermogravimetric analysis

Islam MA, Kabir G, Asif M, Hameed BH

Bioresour Technol, 2015 Oct;194:14-20.
PMID: 26176821 DOI: 10.1016/j.biortech.2015.06.094

This study examined the combustion profile and kinetics of hydrochar produced from hydrothermal carbonisation (HTC) of Karanj fruit hulls (KFH). The HTC-KFH hydrochar combustion kinetics was investigated at 5, 10, and 20°C/min by thermogravimetric analysis. The kinetics model, Kissinger-Akahira-Sunose revealed the combustion kinetics parameters for the extent of conversion from 0.1 to 0.8; the activation energy varies from 114 to 67 kJ/mol respectively. The hydrochar combustion followed multi-steps kinetics; the Coats-Redfern models predicted the activation energies and pre-exponential constants for the hydrochar combustion zones. The diffusion models are the effective mechanism in the second and third zone.
Human colon cancer targeted pro-apoptotic, anti-metastatic and cytostatic effects of binuclear Silver(I)-N-Heterocyclic carbene (NHC) complexes

Asif M, Iqbal MA, Hussein MA, Oon CE, Haque RA, Khadeer Ahamed MB, et al.

Eur J Med Chem, 2016 Jan 27;108:177-187.
PMID: 26649905 DOI: 10.1016/j.ejmech.2015.11.034

The current mechanistic study was conducted to explore the effects of increased lipophilicity of binuclear silver(I)-NHC complexes on cytotoxicity. Two new silver(I)-N-Heterocyclic Carbene (NHC) complexes (3 and 4), having lypophilic terminal alkyl chains (Octyl and Decyl), were derived from meta-xylyl linked bis-benzimidazolium salts (1 and 2). Each of the synthesized compounds was characterized by microanalysis and spectroscopic techniques. The complexes were tested for their cytotoxicity against a panel of human cancer c as well normal cell lines using MTT assay. Based on MTT assay results, complex 4 was found to be selectively toxic towards human colorectal carcinoma cell line (HCT 116). Complex 4 was further studied in detail to explore the mechanism of cell death and findings of the study revealed that complex 4 has promising pro-apoptotic and anti-metastatic activities against HCT 116 cells. Furthermore, it showed pronounced cytostatic effects in HCT 116 multicellular spheroid model. Hence, binuclear silver(I)-NHC complexes with longer terminal aliphatic chains have worth to be further studied against human colon cancer for the purpose of drug development.

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