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Orthosiphon stamineus: traditional uses, phytochemistry, pharmacology, and toxicology

Ameer OZ, Salman IM, Asmawi MZ, Ibraheem ZO, Yam MF

J Med Food, 2012 Aug;15(8):678-90.
PMID: 22846075 DOI: 10.1089/jmf.2011.1973

Orthosiphon stamineus Benth. (Lambiaceae) is an important plant in traditional folk medicine. This review is a comprehensive summary of the currently available chemical, pharmacological, and toxicological investigations as well as the traditional and therapeutic uses of this plant. Different in vitro and in vivo models have been addressed along with a survey of all phytochemicals identified in this plant, including flavonoids, terpenoids, and essential oils. Previous studies revealed that O. stamineus possesses several pharmacological activities, which are attributed to its phytochemical content. It was found that O. stamineus exhibits diuretic, hypouricemic, renal protective, antioxidant, anti-inflammatory, hepatoprotective, gastroprotective, antihypertensive, antidiabetic, antihyperlipidemic, antimicrobial, and anorexic activities. In conclusion, O. stamineus has wide traditional and pharmacological uses in various pathophysiological conditions. Therefore, it is an attractive subject for further experimental and clinical investigations.
Preparation and in vitro evaluation of mebeverine HCl colon-targeted drug delivery system

Abdullah GZ, Abdulkarim MF, Chitneni M, Mutee AF, Ameer OZ, Salman IM, et al.

Pharm Dev Technol, 2011 Aug;16(4):331-42.
PMID: 20429815 DOI: 10.3109/10837451003739255

Mebeverine HCl is a water soluble drug commonly used to treat irritable bowel syndrome by acting directly on the smooth muscles of the colon. This work was aimed at the formulation and in vitro evaluation of a colon-targeted drug delivery system containing mebeverine HCl. Matrix tablets were prepared using ethyl cellulose (EC), Eudragit RL 100 either solely or in combination by wet granulation technique. Dissolution was carried out in 0.1 N HCl for 2?h followed by pH 6.8 phosphate buffer for eight hours. Uncoated forms released more than 5% drug in 0.1 N HCl therefore, Eudragit L100 was used as a coat. The results indicated very slow release profile. As a result, single retardant was used to prepare the matrix and coated by Eudragit L 100. The matrix containing 7% Eudragit RL 100 and 6% of binder was subjected to further studies to assess the effect of different coats (Eudragit L 100-55 and cellulose acetate phthalate) and different binders (pectin and sodium alginate) on the release profile. Eudragit L 100 and pectin were the best coating agent and binder, respectively. The final formula was stable and it can be concluded that the prepared system has the potential to deliver mebeverine HCl in vivo to the colon.
Fulltext Benzyl N-[(Z)-(1-methyl-2-sulfanyl-propyl-idene)amino]-carbamodithio-ate

Break MK, Mehta S, Tahir MI, Crouse KA, Khoo TJ

Acta Crystallogr Sect E Struct Rep Online, 2013 Feb 1;69(Pt 2):o178.
PMID: 23424463 DOI: 10.1107/S1600536812051008

The title compound, C(12)H(16)N(2)S(3), was obtained by the condensation reaction of S-benzyl dithio-carbazate and 3-mercaptobutan-2-one. The phenyl ring and thiol (SH) group are approximately perpendicular [S-C-C-C and N-C-C-S torsion angles = 67.8 (3) and 116.9 (2)°, respectively] to the rest of the mol-ecule. In the crystal, mol-ecules are linked by weak S-H⋯S and N-H⋯S hydrogen bonds, π-π inter-actions between the benzene rings [centroid-centroid distance = 3.823 (2) Å] and C-H⋯π inter-actions.
Fulltext Ethosomal nanocarriers: the impact of constituents and formulation techniques on ethosomal properties, in vivo studies, and clinical trials

Abdulbaqi IM, Darwis Y, Khan NA, Assi RA, Khan AA

Int J Nanomedicine, 2016;11:2279-304.
PMID: 27307730 DOI: 10.2147/IJN.S105016

Ethosomal systems are novel lipid vesicular carriers containing a relatively high percentage of ethanol. These nanocarriers are especially designed for the efficient delivery of therapeutic agents with different physicochemical properties into deep skin layers and across the skin. Ethosomes have undergone extensive research since they were invented in 1996; new compounds were added to their initial formula, which led to the production of new types of ethosomal systems. Different preparation techniques are used in the preparation of these novel carriers. For ease of application and stability, ethosomal dispersions are incorporated into gels, patches, and creams. Highly diverse in vivo models are used to evaluate their efficacy in dermal/transdermal delivery, in addition to clinical trials. This article provides a detailed review of the ethosomal systems and categorizes them on the basis of their constituents to classical ethosomes, binary ethosomes, and transethosomes. The differences among these systems are discussed from several perspectives, including the formulation, size, ζ-potential (zeta potential), entrapment efficiency, skin-permeation properties, and stability. This paper gives a detailed review on the effects of ethosomal system constituents, preparation methods, and their significant roles in determining the final properties of these nanocarriers. Furthermore, the novel pharmaceutical dosage forms of ethosomal gels, patches, and creams are highlighted. The article also provides detailed information regarding the in vivo studies and clinical trials conducted for the evaluation of these vesicular systems.
Molecular dynamics simulations suggest changes in electrostatic interactions as a potential mechanism through which serine phosphorylation inhibits DNA Polymerase β's activity

Homouz D, Joyce-Tan KH, Shahir Shamsir M, Moustafa IM, Idriss H

J Mol Graph Model, 2018 01;79:192.
PMID: 29223917 DOI: 10.1016/j.jmgm.2017.11.002

DNA polymerase β is a 39kDa enzyme that is a major component of Base Excision Repair in human cells. The enzyme comprises two major domains, a 31kDa domain responsible for the polymerase activity and an 8kDa domain, which bind ssDNA and has a deoxyribose phosphate (dRP) lyase activity. DNA polymerase β was shown to be phosphorylated in vitro with protein kinase C (PKC) at serines 44 and 55 (S44 and S55), resulting in loss of its polymerase enzymic activity, but not its ability to bind ssDNA. In this study, we investigate the potential phosphorylation-induced structural changes for DNA polymerase β using molecular dynamics. The simulations show drastic conformational changes of the polymerase structure as a result of S44 phosphorylation. Phosphorylation-induced conformational changes transform the closed (active) enzyme structure into an open one. Further analysis of the results points to a key hydrogen bond and newly formed salt bridges as potential drivers of these structural fluctuations. The changes observed with S44/55 and S55 phosphorylation were less dramatic than S44 and the integrity of the H-bond was not compromised. Thus the phosphorylation of S44 is likely the major contributor to structural fluctuations that lead to loss of enzymatic activity.
Molecular dynamics simulations suggest changes in electrostatic interactions as a potential mechanism through which serine phosphorylation inhibits DNA polymerase β activity

Homouz D, Joyce-Tan KH, ShahirShamsir M, Moustafa IM, Idriss HT

J Mol Graph Model, 2018 09;84:236-241.
PMID: 30138833 DOI: 10.1016/j.jmgm.2018.08.007

DNA polymerase β is a 39 kDa enzyme that is a major component of Base Excision Repair in human cells. The enzyme comprises two major domains, a 31 kDa domain responsible for the polymerase activity and an 8 kDa domain, which bind ssDNA and has a deoxyribose phosphate (dRP) lyase activity. DNA polymerase β was shown to be phosphorylated in vitro with protein kinase C (PKC) at serines 44 and 55 (S44 and S55), resulting in loss of its polymerase enzymic activity, but not its ability to bind ssDNA. In this study, we investigate the potential phosphorylation-induced structural changes for DNA polymerase β using molecular dynamics simulations. The simulations show drastic conformational changes of the polymerase structure as a result of S44 phosphorylation. Phosphorylation-induced conformational changes transform the closed (active) enzyme structure into an open one. Further analysis of the results points to a key hydrogen bond and newly formed salt bridges as potential drivers of these structural fluctuations. The changes observed with S55/44 and S55 phosphorylation were less dramatic and the integrity of the H-bond was not compromised. Thus the phosphorylation of S44 is the major contributor to structural fluctuations that lead to loss of enzymatic activity.
Fulltext Pulmonary Delivery of Anticancer Drugs via Lipid-Based Nanocarriers for the Treatment of Lung Cancer: An Update

Abdulbaqi IM, Assi RA, Yaghmur A, Darwis Y, Mohtar N, Parumasivam T, et al.

Pharmaceuticals (Basel), 2021 Jul 27;14(8).
PMID: 34451824 DOI: 10.3390/ph14080725

Lung cancer (LC) is the leading cause of cancer-related deaths, responsible for approximately 18.4% of all cancer mortalities in both sexes combined. The use of systemic therapeutics remains one of the primary treatments for LC. However, the therapeutic efficacy of these agents is limited due to their associated severe adverse effects, systemic toxicity and poor selectivity. In contrast, pulmonary delivery of anticancer drugs can provide many advantages over conventional routes. The inhalation route allows the direct delivery of chemotherapeutic agents to the target LC cells with high local concertation that may enhance the antitumor activity and lead to lower dosing and fewer systemic toxicities. Nevertheless, this route faces by many physiological barriers and technological challenges that may significantly affect the lung deposition, retention, and efficacy of anticancer drugs. The use of lipid-based nanocarriers could potentially overcome these problems owing to their unique characteristics, such as the ability to entrap drugs with various physicochemical properties, and their enhanced permeability and retention (EPR) effect for passive targeting. Besides, they can be functionalized with different targeting moieties for active targeting. This article highlights the physiological, physicochemical, and technological considerations for efficient inhalable anticancer delivery using lipid-based nanocarriers and their cutting-edge role in LC treatment.
Fulltext Lyophilized Hybrid Nanostructured Lipid Carriers to Enhance the Cellular Uptake of Verapamil: Statistical Optimization and In Vitro Evaluation

Khan AA, Abdulbaqi IM, Abou Assi R, Murugaiyah V, Darwis Y

Nanoscale Res Lett, 2018 Oct 15;13(1):323.
PMID: 30324291 DOI: 10.1186/s11671-018-2744-6

Verapamil is a calcium channel blocker and highly effective in the treatment of hypertension, angina pectoris, and other diseases. However, the drug has a low bioavailability of 20 to 35% due to the first pass effect. The main objective of this study was to develop hybrid verapamil-dextran nanostructured lipid carriers (HVD-NLCs) in an attempt to increase verapamil cellular uptake. The formulations were successfully prepared by a high-shear homogenization method and statistically optimized using 24 full factorial design. The HVD-NLCs formulations were freeze-dried using trehalose as a cryoprotectant. The results showed that the optimized formula (VER-9) possessed a particle size (PS), polydispersity index (PDI), and the percentage of entrapment efficiency (%EE) of 192.29 ± 2.98, 0.553 ± 0.075, and 93.26 ± 2.66%, respectively. The incorporation of dextran sulfate in the formulation had prolonged the release of verapamil (~ 85% in 48 h) in the simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8). The differential scanning calorimetry analysis showed no chemical interaction between verapamil and the excipients in the formulation. While wide-angle X-ray scattering studies demonstrated the drug in the amorphous form after the incorporation in the NLCs. The transmission electron microscopy and scanning electron microscopy images revealed that the nanoparticles had spherical shape. The cellular uptake study using Caco-2 cell line showed a higher verapamil uptake from HVD-NLCs as compared to verapamil solution and verapamil-dextran complex. The optimized formulation (VER-9) stored in the refrigerated condition (5 °C ± 3 °C) was stable for 6 months. In conclusion, the HVD-NLCs were potential carriers for verapamil as they significantly enhanced the cellular uptake of the drug.
Fulltext Thermo-mechanical contact problems and elastic behaviour of single and double sides functionally graded brake disks with temperature-dependent material properties

Bayat M, Alarifi IM, Khalili AA, El-Bagory TMAA, Nguyen HM, Asadi A

Sci Rep, 2019 Oct 25;9(1):15317.
PMID: 31653877 DOI: 10.1038/s41598-019-51450-z

A thermo-elastic contact problem of functionally graded materials (FGMs) rotating brake disk with different pure brake pad areas under temperature dependent material properties is solved by Finite Element Method (FEM). The properties of brake disk change gradually from metal to ceramic by power-law distribution along the radial direction from the inner to the outer surface. Areas of the pure pad are changing while the vertical force is constant. The ratio of brake pad thickness to FGMs brake disk thickness is assumed 0.66. Two sources of thermal loads are considered: (1) Heat generation between the pad and brake disk due to contact friction, and (2) External thermal load due to a constant temperature at inner and outer surfaces. Mechanical responses of FGMs disk are compared with several pad contact areas. The results for temperature-dependent and temperature-independent material properties are investigated and presented. The results show that the absolute value of the shear stress in temperature-dependent material can be greater than that for temperature-independent material. The radial stress for some specific grading index (n = 1.5) is compressive near the inner surface for double contact while it is tensile for a single contact. It is concluded that the radial strain for some specific value of grading index (n = 1) is lower than other FGMs and pure double side contact brake disks.
Genotoxic effects of Dukhan: A smoke bath from the wood of Acacia seyal used traditionally by Sudanese women

Elgorashi EE, Eldeen IMS, Makhafola TJ, Eloff JN, Verschaeve L

J Ethnopharmacol, 2022 Mar 01;285:114868.
PMID: 34826541 DOI: 10.1016/j.jep.2021.114868

ETHNOBOTANICAL RELEVANCE: Smoke from the wood of Acacia seyal Delile has been used by Sudanese women for making a smoke bath locally called Dukhan. The ritual is performed to relieve rheumatic pain, smooth skin, heal wounds and achieve general body relaxation.
AIM OF THE STUDY: The present study was designed to investigate the in vitro anti-inflammatory effect of the smoke condensate using cyclooxygenase -1 (COX-1) and -2 (COX-2) as well as its potential genotoxic effects using the bacterial-based Ames test and the mammalian cells-based micronucleus/cytome and comet assays.
MATERIAL AND METHODS: The smoke was prepared in a similar way to that commonly used traditionally by Sudanese women then condensed using a funnel. Cyclooxygenase assay was used to evaluate its in vitro anti-inflammatory activity. The neutral red uptake assay was conducted to determine the range of concentrations in the mammalian cells-based assays. The Ames, cytome and comet assays were used to assess its potential adverse (long-term) effects.
RESULTS: The smoke condensate did not inhibit the cyclooxygenases at the highest concentration tested. All smoke condensate concentrations tested in the Salmonella/microsome assay induced mutation in both TA98 and TA100 in a dose dependent manner. A significant increase in the frequency of micronucleated cells, nucleoplasmic bridges and nuclear buds was observed in the cytome assay as well as in the % DNA damage in the comet assay.
CONCLUSIONS: The findings indicated a dose dependent genotoxic potential of the smoke condensate in the bacterial and human C3A cells and may pose a health risk to women since the smoke bath is frequently practised. The study highlighted the need for further rigorous assessment of the risks associated with the smoke bath practice.
Organic Geochemistry and 1-D Basin Modeling of the Late Triassic Baluti Formation: Implication of Shale Oil Potential in the Kurdistan Region of Iraq

Mohialdeen IMJ, Hakimi MH, Fatah SS, Abdula RA, Khanaqa PA, Lathbl MA, et al.

ACS Omega, 2024 Feb 13;9(6):7085-7107.
PMID: 38371760 DOI: 10.1021/acsomega.3c09003

This investigation looks at the Late Triassic Baluti Formation's organic geochemical, mineralogical, and petrographical characteristics from a single exploration well (TT-22) near the Taq Taq oilfield in northern Iraq. The Baluti Formation shale samples that were studied in the studied well have high total organic carbon (TOC %) values up to 4.92 wt % and mostly hydrogen-rich types I and II kerogen with a minor gradient to types II/III and III kerogen, indicating a good oil-source rock. The hydrogen-rich kerogen was also confirmed by various organic matter (OM) origins and depositional environment-related biomarkers. The biomarker indicators demonstrate that the Baluti shale was deposited under anoxic conditions and contains a variety of OM generated mostly from algae marine and other aqueous organic materials, along with some terrigenous land plants. The geochemical and optical maturity indicators show that most of the examined Baluti shale samples, with a deep burial depth of more than 4000 m, are thermally mature, thus defining peak-mature to late-mature stages of the oil generation window. According to the basin models, from the late Miocene to the present, between 10 and 59% of the kerogen in the Baluti shale source rock has been transformed into oil, which is consistent with the VR values between 0.77 and 1.08%. The presence of the oil crossover in these shale rocks with an oil saturation index of more than 100 mg HC/g rock supports the maximal oil generation from the Baluti source rock system. Additionally, there was little oil expulsion from the Baluti source rock system at the end of the late Miocene, with transformation ratio values below 60% (59%). Considering the more significant oil generation and little expulsion, a high pressure was generated and forced the brittle minerals of the Baluti shales (mainly quartz), creating a natural fracture system as recognized and observed in the thin section. This natural fracture system enhances the porosity system of tight shale rocks of the Baluti Formation, giving rise to a high probability of oil production using hydraulic fracturing stimulation.
Fulltext Bis{(Z)-[(E)-2-(pyridin-2-yl-methyl-idene)hydrazin-1-yl-idene][(pyridin-2-yl)methyl-sulfan-yl]methane-thiol-ato}nickel(II)

Khoo TJ, Break MK, Tahir MI, Krouse KA, Cowley AR, Watkin DJ

Acta Crystallogr Sect E Struct Rep Online, 2013 Jun 01;69(Pt 6):m323-4.
PMID: 23794987 DOI: 10.1107/S1600536813013032

The title compound, [Ni(C13H11N4S2)2], was obtained by the reaction of S-2-picolyldi-thio-carbazate and pyridine-2-carbaldehyde with nickel(II) acetate. The Ni(II) atom is located on a twofold rotation axis and is bonded to four N atoms at distances of 2.037 (8) and 2.109 (9) Å, and to two S atoms at a distance of 2.406 (3) Å, leading to a distorted octa-hedral coordination. The angle between the mean planes of the coordinating moieties of the two symmetry-related tridentate ligands is 83.3 (2)°. In the crystal, complex mol-ecules are linked by weak C-H⋯S hydrogen bonds, π-π inter-actions between the pyridine rings [centroid-centroid distance = 3.775 (9) Å] and C-H⋯π inter-actions. The hydrogen-bonding inter-actions lead to the formation of layers parallel to (010); π-π inter-actions link these layers into a three-dimensional network.
Salvia officinalis L. Methanolic Extract Reduces Lead and Nicotine-Induced Sperm Quality Degeneration in Male Rats

Ammar Aldaddou W, Aljohani ASM, Adewale Ahmed I, Al-Wabel NA, El-Ashmawy IM

Chem Biodivers, 2023 Jul;20(7):e202300115.
PMID: 37236909 DOI: 10.1002/cbdv.202300115

Most heavy metals and industrial chemicals such as nicotine and lead cause harm to the reproduction process through a decrease in sperm motility, fertilization process, and sperm binding to the oocyte. Salvia officinalis L. (sage) has been reported to enhance serum testosterone levels and other certain biochemical enzymes. Thus, the current study is aimed at evaluating the potential health benefits of S. officinalis L. methanol extract on lead and nicotine hydrogen tartrate-induced sperm quality degeneration in male rats and also identifying some of the non-polar volatile bioactive compounds that might be attributed to the bioactivity of S. officinalis extract using gas chromatography-mass spectrometry (GC/MS). In the study, fifty-four mature male albino rats of about 220-250 g [were divided randomly and equally into 9 groups (n=6)]. Sperm quality degeneration was induced through the oral administration of 1.5 g/L of lead acetate in drinking water or peritoneal injection of 0.50 mg/kg (animal weight) nicotine hydrogen tartrate for sixty days. Two doses (200 & 400 mg/kg b.w.) of S. officinalis L. were used. The rats were anesthetized after the experimental period and then sacrificed. Blood samples were collected while the epididymis, testicle, and accessory sex organs (prostates and seminal vesical) were taken for histopathological studies. Twelve major compounds were identified through the GC/MS analysis of S. officinalis L. methanol extract. Lead and nicotine toxicity had a great effect on the rats' sperm quality causing a significant (p<0.05) decrease in the quantity of sperm and sperm motility as well as an upsurge in the abnormalities of the sperm and a reduction in the length & diameter of seminiferous tubules and size & weight of sexual organs (accessory sex glands, epididymis, and testis). The administration of S. officinalis L. methanol extract, however, had a positive impact on the sexual organ weights, semen quality & quantity, and rats' fertility, thus, ameliorating the adversative effects of both lead and nicotine. Further evaluation and isolation of the bioactive components are recommended as potential drug leads.
Breaking barriers: bilosomes gel potentials to pave the way for transdermal breast cancer treatment with Tamoxifen

Abou Assi R, Abdulbaqi IM, Tan SM, Wahab HA, Darwis Y, Chan SY

Drug Dev Ind Pharm, 2023 Sep 18.
PMID: 37722711 DOI: 10.1080/03639045.2023.2256404

OBJECTIVE: Breast cancer affects women globally, regardless of age or location. On the other hand, Tamoxifen (TXN), a class II biopharmaceutical drug is acting as a prophylactic/treating agent for women at risk of and/or with hormone receptor-positive breast cancer. However, its oral administration has life-threatening side effects, which have led researchers to investigate alternative delivery methods. One such method is transdermal drug delivery utilizing bile salts as penetration enhancers, aka Bilosomes.
METHODS: Bilosomes formulations were optimized statistically for the outcome of vesicle shape, size, and entrapment efficiency using two types of bile, i.e. sodium taurocholate and sodium cholate. These bilosomes were then loaded into HPMC base gel and further characterized for their morphology, drug content, pH, viscosity, spreadability and eventually ex-vivo skin penetration and deposition studies.
RESULTS: Findings showed that sodium cholate has superiority as a penetration enhancer over sodium taurocholate in terms of morphological characterizes, zeta potential, and cumulative amounts of tamoxifen permeated per unit area (15.13 ± 0.71 μg/cm2 and 6.51 ± 0.6 μg/cm2 respectively). In fact, bilosomes designed with sodium cholate provided around 9 folds of skin deposition compared to TXN non-bilosomal gel.
CONCLUSION: Bilosomes gels could be a promising option for locally delivering tamoxifen to the breast through the skin, offering an encouraging transdermal solution.
An application of carbohydrate polymers-based surface-modified gold nanoparticles for improved target delivery to liver cancer therapy - A systemic review

Alzahrani AR, Ibrahim IAA, Shahzad N, Shahid I, Alanazi IM, Falemban AH, et al.

Int J Biol Macromol, 2023 Sep 13;253(Pt 4):126889.
PMID: 37714232 DOI: 10.1016/j.ijbiomac.2023.126889

Gold nanoparticles have been broadly investigated as cancer diagnostic and therapeutic agents. Gold nanoparticles are a favorable drug delivery vehicle with their unique subcellular size and good biocompatibility. Chitosan, agarose, fucoidan, porphyran, carrageenan, ulvan and alginate are all examples of biologically active macromolecules. Since they are biocompatible, biodegradable, and irritant-free, they find extensive application in biomedical and macromolecules. The versatility of these compounds is enhanced because they are amenable to modification by functional groups like sulfation, acetylation, and carboxylation. In an eco-friendly preparation process, the biocompatibility and targeting of GNPs can be improved by functionalizing them with polysaccharides. This article provides an update on using carbohydrate-based GNPs in liver cancer treatment, imaging, and drug administration. Selective surface modification of several carbohydrate types and further biological uses of GNPs are focused on.
Fulltext Costs associated with tuberculosis diagnosis and treatment in Yemen for patients and public health services

Othman GQ, Ibrahim MI, Raja'a YA

East Mediterr Health J, 2012 Apr;18(4):393-8.
PMID: 22768704

This study determined the costs associated with tuberculosis (TB) diagnosis and treatment for the public health services and patients in Sana'a, Yemen. Data were collected prospectively from 320 pulmonary and extrapulmonary TB patients (160 each) who were followed until completion of treatment. Direct medical and nonmedical costs and indirect costs were calculated. The proportionate cost to the patients for pulmonary TB and extrapulmonary TB was 76.1% arid 89.4% respectively of the total for treatment. The mean cost to patients for pulmonary and extrapulmonary TB treatment was US$ 108.4 and US$ 328.0 respectively. The mean cost per patient to the health services for pulmonary and extrapulmonary TB treatment was US$ 34.0 and US$ 38.8 respectively. For pulmonary and extrapulmonary TB, drug treatment represented 59.3% and 77.9% respectively of the total cost to the health services. The greatest proportionate cost to patients for pulmonary TB treatment was time away from work (67.5% of the total cost), and for extrapulmonary TB was laboratory and X-ray costs (55.5%) followed by transportation (28.6%).
Environmental degradation of microbial polyhydroxyalkanoates and oil palm-based composites

Salim YS, Sharon A, Vigneswari S, Mohamad Ibrahim MN, Amirul AA

Appl Biochem Biotechnol, 2012 May;167(2):314-26.
PMID: 22544728 DOI: 10.1007/s12010-012-9688-6

This paper investigates the degradation of polyhydroxyalkanoates and its biofiber composites in both soil and lake environment. Time-dependent changes in the weight loss of films were monitored. The rate of degradation of poly(3-hydroxybutyrate) [P(3HB)], poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-23 mol% 4HB)] and poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-9 mol% 3HV-co-19 mol% 4HB)] were investigated. The rate of degradation in the lake is higher compared to that in the soil. The highest rate of degradation in lake environment (15.6% w/w week(-1)) was observed with P(3HB-co-3HV-co-4HB) terpolymer. Additionally, the rate of degradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-38 mol% 3HV)] was compared to PHBV biofiber composites containing compatibilizers and empty fruit bunch (EFB). Here, composites with 30% EFB displayed the highest rate of degradation both in the lake (25.6% w/w week(-1)) and soil (15.6% w/w week(-1)) environment.
Fulltext Candida glabrata endophthalmitis following penetrating keratoplasty in a patient with negative donor rim culture

Muzaliha MN, Adil H, Ibrahim M, Shatriah I

BMC Ophthalmol, 2010;10:18.
PMID: 20537193 DOI: 10.1186/1471-2415-10-18

Candida glabrata endophthalmitis following keratoplasty is rare and almost always associated with positive donor rim culture.
Fulltext Breast cancer in malaysia: are our women getting the right message? 10 year-experience in a single institution in Malaysia

Taib NA, Yip CH, Ibrahim M, Ng CJ, Farizah H

Asian Pac J Cancer Prev, 2007 Jan-Mar;8(1):141-5.
PMID: 17477791

The message that health care providers caring for patients with breast cancer would like to put forth, is that, not only early detection is crucial but early treatment too is important in ensuring survival. This paper examines the pattern of presentation at a single institution over a 10-year period from 1995 to 2005. In Malaysia, education outreach programmes are ongoing, with contributions not only from the public sector, but also private enterprise. Articles on breast cancer in local newspapers and women magazines and television are quite commonplace. However are our women getting the right message? Now is an appropriate time to bring the stakeholders together to formulate a way to reach all women in Malaysia, not excluding the fact that we are from different races, different education levels and backgrounds requiring differing ways of delivering health promotion messages. To answer the question of why women present late, we prospectively studied 25 women who presented with locally advanced disease. A quantitative, quasi-qualitative study was embarked upon, as a prelude to a more detailed study. Reasons for presenting late were recorded. We also looked at the pattern of presentation of breast lumps in women to our breast clinic in UMMC and in the surgical clinic in Hospital Kota Bharu, in the smaller capital of the state of Kelantan, in 2003. There is hope for the future, the government being a socially responsible one is currently making efforts towards mammographic screening in Malaysia. However understanding of the disease, acceptance of medical treatment and providing resources is imperative to ensure that health behaviour exhibited by our women is not self-destructive but self-preserving. Women are an integral part of not only the nation's workforce but the lifeline of the family - hopefully in the next decade we will see great improvement in the survival of Malaysian women with breast cancer.
The effect of nitric oxide on the production of cyclic AMP by a human osteoblast (HOS) cell line stimulated with hydroxyapatite

Sosroseno W, Sugiatno E, Samsudin AR, Ibrahim MF

Biomed Pharmacother, 2008 Jun;62(5):328-32.
PMID: 17988826

The aim of the present study was to determine the effect of nitric oxide (NO) on the production of cyclic AMP (cAMP) by a human osteoblast cell line (HOS cells) stimulated with hydroxyapatite. Cells were cultured on the HA surfaces with or without the presence of NO donors (SNAP and NAP) for 3 days. The effect of adenylyl cyclase inhibitor (SQ22536), NO scavenger (carboxy PTIO) or endothelial nitric oxide synthase (eNOS) inhibitor (L-NIO), was assessed by adding these to the cultures of HA-stimulated HOS cells with or without the presence of SNAP. Furthermore, HOS cells were pre-treated with anti-human integrin alphaV antibody prior to culturing on HA surfaces with or without the presence of SNAP. The levels of cAMP and cGMP were determined from the 3-day culture supernatants. The results showed that the production of cAMP but not cGMP by HA-stimulated HOS cells was augmented by SNAP. SQ22536 and carboxy PTIO suppressed but L-NIO only partially inhibited the production of cAMP by HA-stimulated HOS cells with or without the presence of exogenous NO. Pre-treatment of the cells with anti-human integrin alphaV antibody suppressed the production of cAMP by HA-stimulated HOS cells with or without the presence of NO. Therefore, the results of the present study suggest that NO may up-regulate the production of cAMP, perhaps, by augmenting adenylyl cyclase activity initiated by the binding between HOS cell-derived integrin alphaV and HA surface.

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