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Fulltext Prevalence and associated risk factors of Giardia infection among indigenous communities in rural Malaysia

Choy SH, Al-Mekhlafi HM, Mahdy MA, Nasr NN, Sulaiman M, Lim YA, et al.

Sci Rep, 2014;4:6909.
PMID: 25366301 DOI: 10.1038/srep06909

This study was carried out to investigate the prevalence and risk factors of Giardia infection among indigenous people in rural Malaysia. Faecal samples were collected from 1,330 participants from seven states of Malaysia and examined by wet mount and formalin-ether sedimentation methods while demographic, socioeconomic and environmental information was collected using a pre-tested questionnaire. The overall prevalence of Giardia infection was 11.6% and was significantly higher among those aged ≤ 12 years compared to their older counterparts. Multivariate logistic regression identified age of ≤ 12 years, lacking of toilet at household, not washing hands before eating, not washing hands after playing with animals, not boiling water before consumption, bathing in the river, and not wearing shoes when outside as the significant risk factors of Giardia infection among these communities. Based on a multilocus genotyping approach (including tpi, gdh and bg gene sequences), 69 isolates were identified as assemblage A, and 69 as assemblage B. No association between the assemblages and presence of symptoms was found. Providing proper sanitation, as well as provision of clean drinking water and proper health education regarding good personal hygiene practices will help significantly in reducing the prevalence and burden of Giardia infection in these communities.
The synthetic curcuminoid BHMC restores endotoxin-stimulated HUVEC dysfunction:Specific disruption on enzymatic activity of p38 MAPK

Tham CL, Hazeera Harith H, Wai Lam K, Joong Chong Y, Singh Cheema M, Roslan Sulaiman M, et al.

Eur J Pharmacol, 2015 Feb 15;749:1-11.
PMID: 25560198 DOI: 10.1016/j.ejphar.2014.12.015

2,6-bis-(4-hydroxyl-3-methoxybenzylidine)cyclohexanone (BHMC) has been proven to selectively inhibit the synthesis of proinflammatory mediators in lipopolysaccharide-induced U937 monocytes through specific interruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and improves the survival rate in a murine lethal sepsis model. The present study addressed the effects of BHMC upon lipopolysaccharide-induced endothelial dysfunction in human umbilical vein endothelial cells to determine the underlying mechanisms. The cytotoxicity effect of BHMC on HUVEC were determined by MTT assay. The effects of BHMC on endothelial dysfunction induced by lipopolysaccharide such as endothelial hyperpermeability, monocyte-endothelial adhesion, transendothelial migration, up-regulation of adhesion molecules and chemokines were evaluated. The effects of BHMC at transcriptional and post-translational levels were determined by Reverse Transcriptase-Polymerase Chain Reaction and Western Blots. The mode of action of BHMC was dissected by looking into the activation of Nuclear Factor-kappa B and Mitogen-Activated Protein Kinases. BHMC concentration-dependently reduced endothelial hyperpermeability, leukocyte-endothelial cell adhesion and monocyte transendothelial migration through inhibition of the protein expression of adhesion molecules (Intercellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule-1) and secretion of chemokines (Monocyte Chemotactic Protein-1) at the transcriptional level. BHMC restored endothelial dysfunction via selective inhibition of p38 Mitogen-Activated Protein Kinase enzymatic activity which indirectly prevents the activation of Nuclear Factor-kappaB and Activator Protein-1 transcription factors. These findings further support earlier observations on the inhibition of BHMC on inflammatory events through specific disruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and provide new insights into the inhibitory effects of BHMC on lipopolysaccharide-induced endothelial dysfunction.
Fulltext In vivo analgesic effect of aqueous extract of Tamarindus indica L. fruits

Khalid S, Shaik Mossadeq WM, Israf DA, Hashim P, Rejab S, Shaberi AM, et al.

Med Princ Pract, 2010;19(4):255-9.
PMID: 20516700 DOI: 10.1159/000312710

To study the effects of Tamarindus indica L. aqueous fruit extract on the antinociceptive activities in rodent models.
Anti-inflammatory and antinociceptive effects of Mitragyna speciosa Korth methanolic extract

Shaik Mossadeq WM, Sulaiman MR, Tengku Mohamad TA, Chiong HS, Zakaria ZA, Jabit ML, et al.

Med Princ Pract, 2009;18(5):378-84.
PMID: 19648761 DOI: 10.1159/000226292

OBJECTIVES: To determine the anti-inflammatory and antinociceptive activities of Mitragyna speciosa Korth methanol extract in rodents.
MATERIALS AND METHODS: Anti-inflammatory activity was evaluated using carrageenan-induced paw edema and cotton pellet-induced granuloma tests in rats. Antinociceptive activity was measured using the writhing test and the hot plate test in mice, and the formalin test in rats. All drugs and extracts were diluted in dH(2)O and administered through the intraperitoneal route. Results were analyzed using one-way ANOVA followed by Dunnett's test for multiple comparisons among groups.
RESULTS: Results showed that intraperitoneal administration of the extract at doses of 100 and 200 mg/kg produced significant dose-dependent activity in all of the nociceptive models evaluated (p < 0.05). With the formalin test, the antinociceptive activity in mice was inhibited only at the highest dose of the extract (200 mg/kg). The study also showed that intraperitoneal administration of the methanol extract of M. speciosa (100 and 200 mg/kg) significantly and dose-dependently suppressed the development of carrageenan-induced rat paw edema (p < 0.05). In the chronic test, however, significant reduction in granulomatous tissue formation in rats was observed only at the highest dose of the methanol extract of M. speciosa (200 mg/kg, p < 0.05).
CONCLUSION: The present study suggests the presence of potent antinociceptive and anti-inflammatory principles in the extract, supporting its folkloric use for the treatment of these conditions.
Effects of various nonopioid receptor antagonists on the antinociceptive activity of Muntingia calabura extracts in mice

Zakaria ZA, Hassan MH, Nurul Aqmar MN, Abd Ghani M, Mohd Zaid SN, Sulaiman MR, et al.

Methods Find Exp Clin Pharmacol, 2007 Oct;29(8):515-20.
PMID: 18040526

This study was carried out in mice to determine the nonopioid receptor signaling pathway(s) that might modulate the antinociceptive activity of the aqueous and chloroform extracts of Muntingia calabura (M. calabura) leaves, using the hot-plate test. The leaves of M. calabura were sequentially soaked [1:2 (w/v); 72 h] in distilled water (dH(2)O) and chloroform. The 50% concentration extracts were selected for this study based on the plant's previously established antinociceptive profiles. The mice (n = 7) were pretreated (s.c.) for 10 min with the selected nonopioid receptor antagonists, followed by the (s.c.) administration of the respective extract. The latency of discomfort was recorded at the interval time of 0.5, 1, 2, 3, 4 and 5 h after the extract administration. The 5 mg/kg atropine, 10 mg/kg phenoxybenzamine, 10 mg/kg yohimbine, 10 mg/kg pindolol, 1 mg/kg haloperidol and 10 mg/kg bicuculline caused significant (p < 0.05) reduction in the aqueous extract-induced antinociceptive activity. The 10 mg/kg phenoxybenzamine, 10 mg/kg yohimbine, 10 mg/kg pindolol and 10 mg/kg bicuculline caused significant (p < 0.05) reduction in the chloroform extract-induced antinociceptive activity. In conclusion, the central antinociceptive activity of M. calabura leaves appears to be involved in the modulation of various nonopioid receptor signaling pathways. Its aqueous extract antinociceptive activity is mediated via modulation of the muscarinic, alpha(1)-adrenergic, alpha(2)-adrenergic, beta-adrenergic, dopaminergic and GABAergic receptors, while its chloroform extract activity is mediated via modulation of the alpha(1)-adrenergic, alpha(2)-adrenergic, beta-adrenergic and GABAergic receptors.
Fulltext High Cyclability Energy Storage Device with Optimized Hydroxyethyl Cellulose-Dextran-Based Polymer Electrolytes: Structural, Electrical and Electrochemical Investigations

Azha MAS, Dannoun EMA, Aziz SB, Kadir MFZ, Zaki ZI, El-Bahy ZM, et al.

Polymers (Basel), 2021 Oct 19;13(20).
PMID: 34685361 DOI: 10.3390/polym13203602

The preparation of a dextran (Dex)-hydroxyethyl cellulose (HEC) blend impregnated with ammonium bromide (NH4Br) is done via the solution cast method. The phases due to crystalline and amorphous regions were separated and used to estimate the degree of crystallinity. The most amorphous blend was discovered to be a blend of 40 wt% Dex and 60 wt% HEC. This polymer blend serves as the channel for ions to be conducted and electrodes separator. The conductivity has been optimized at (1.47 ± 0.12) × 10-4 S cm-1 with 20 wt% NH4Br. The EIS plots were fitted with EEC circuits. The DC conductivity against 1000/T follows the Arrhenius model. The highest conducting electrolyte possesses an ionic number density and mobility of 1.58 × 1021 cm-3 and 6.27 × 10-7 V-1s-1 cm2, respectively. The TNM and LSV investigations were carried out on the highest conducting system. A non-Faradic behavior was predicted from the CV pattern. The fabricated electrical double layer capacitor (EDLC) achieved 8000 cycles, with a specific capacitance, internal resistance, energy density, and power density of 31.7 F g-1, 80 Ω, 3.18 Wh kg-1, and 922.22 W kg-1, respectively.
In vitro antiproliferative and antioxidant activities of the extracts of Muntingia calabura leaves

Zakaria ZA, Mohamed AM, Jamil NS, Rofiee MS, Hussain MK, Sulaiman MR, et al.

Am J Chin Med, 2011;39(1):183-200.
PMID: 21213408

The in vitro antiproliferative and antioxidant activities of the aqueous, chloroform and methanol extracts of Muntingia calabura leaves were determined in the present study. Assessed using the 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay, the aqueous and methanol extracts of M. calabura inhibited the proliferation of MCF-7, HeLa, HT-29, HL-60 and K-562 cancer cells while the chloroform extract only inhibited the proliferation of MCF-7, HeLa, HL-60 and K-562 cancer cells. Interestingly, all extracts of M. calabura, which failed to inhibit the MDA-MB-231 cells proliferation, did not inhibit the proliferation of 3T3 (normal) cells, indicating its safety. All extracts (20, 100 and 500 μg/ml) were found to possess antioxidant activity when tested using the DPPH radical scavenging and superoxide scavenging assays with the methanol, followed by the aqueous and chloroform, extract exhibiting the highest antioxidant activity in both assays. The total phenolic content for the aqueous, methanol and chloroform extracts were 2970.4 ± 6.6, 1279.9 ± 6.1 and 2978.1 ± 4.3 mg/100 g gallic acid, respectively. In conclusion, the M. calabura leaves possess potential antiproliferative and antioxidant activities that could be attributed to its high content of phenolic compounds, and thus, needs to be further explored.
Heroin in Malaysia and Singapore

Sulaiman M, Kunalan V, Yap ATW, Lim WJL, Ng JJY, Loh SWX, et al.

Drug Test Anal, 2018 Jan;10(1):109-119.
PMID: 28670869 DOI: 10.1002/dta.2238

Clandestine heroin laboratories have been a feature of the Malaysian illicit drug scene since soon after the abuse of heroin emerged in 1972. The first few clandestine heroin laboratories which synthesised heroin via the acetylation of imported morphine were uncovered in 1973 and 1977. By the mid-1980s, this type of laboratory was replaced by heroin-cutting laboratories whereby imported high-grade heroin was cut to street heroin. This was to meet the rising demand for the drug owing to the rapid escalation of the number of drug users. Over the years, the most significant change in the composition of the street heroin is the decrease in its purity from 30%-50% to 3%-5%. Caffeine has remained the major adulterant and chloroquine is detected in virtually all recent seizures.
Fulltext A Novel Design and Development of a Strip-Fed Circularly Polarized Rectangular Dielectric Resonator Antenna for 5G NR Sub-6 GHz Band Applications

Illahi U, Iqbal J, Irfan M, Ismail Sulaiman M, Khan MA, Rauf A, et al.

Sensors (Basel), 2022 Jul 25;22(15).
PMID: 35898037 DOI: 10.3390/s22155531

In this article, a rectangular dielectric resonator antenna (RDRA) with circularly polarized (CP) response is presented for 5G NR (New Radio) Sub-6 GHz band applications. A uniquely shaped conformal metal feeding strip is proposed to excite the RDRA in higher-order mode for high gain utilization. By using the proposed feeding mechanism, the degenerate mode pair of the first higher-order, i.e., TEδ13x at 4.13 GHz and TE1δ3y, at 4.52 GHz is excited to achieve a circularly polarized response. A circular polarization over a bandwidth of ~10%, in conjunction with a wide impedance matching over a bandwidth of ~17%, were attained by the antenna. The CP antenna proposed offers a useful gain of ~6.2 dBic. The achieved CP bandwidth of the RDRA is good enough to cover the targeted 5G NR bands around 4.4−4.8 GHz, such as n79. The proposed antenna configuration is modelled and optimized using computer simulation technology (CST). A prototype was built to confirm (validate) the performance estimated through simulation. A good agreement was observed between simulated and measured results.
Atrovirinone inhibits pro-inflammatory mediator release from murine macrophages and human whole blood

Syahida A, Israf DA, Permana D, Lajis NH, Khozirah S, Afiza AW, et al.

Immunol Cell Biol, 2006 Jun;84(3):250-8.
PMID: 16509831

Many plant-derived natural compounds have been reported previously to inhibit the production of important pro-inflammatory mediators such as nitric oxide, prostaglandin E2, TNF-alpha and reactive oxygen species by suppressing inducible enzyme expression via inhibition of the mitogen-activated protein kinase pathway and nuclear translocation of critical transcription factors. This study evaluates the effects of atrovirinone [2-(1-methoxycarbonyl-4,6-dihydroxyphenoxy)-3-methoxy-5,6-di-(3-methyl-2-butenyl)-1,4-benzoquinone)], a benzoquinone that we have previously isolated from Garcinia atroviridis, on two cellular systems that are repeatedly used in the analysis of anti-inflammatory bioactive compounds, namely, RAW 264.7 macrophage cells and whole blood. Atrovirinone inhibited the production of both nitric oxide and prostaglandin E2 from LPS-induced and IFN-gamma-induced RAW 264.7 cells and whole blood, with inhibitory concentration (IC)50 values of 4.62 +/- 0.65 and 9.33 +/- 1.47 micromol/L, respectively. Analysis of thromboxane B2 (TXB2) secretion from whole blood stimulated by either the cyclooxygenase (COX)-1 or the COX-2 pathway showed that atrovirinone inhibits the generation of TXB2 by both pathways, with IC50 values of 7.41 +/- 0.92 and 2.10 +/- 0.48 micromol/L, respectively. Analysis of IC50 ratios showed that atrovirinone was more COX-2 selective in its inhibition of TXB2, with a ratio of 0.32. Atrovirinone also inhibited the generation of intracellular reactive oxygen species and the secretion of TNF-alpha from RAW 264.7 cells in a dose-responsive manner, with IC50 values of 5.99 +/- 0.62 and 11.56 +/- 0.04 micromol/L, respectively. Lipoxygenase activity was also moderately inhibited by atrovirinone. Our results suggest that atrovirinone acts on important pro-inflammatory mediators possibly by the inhibition of the nuclear factor-kappaB pathway and also by the inhibition of the COX/lipoxygenase enzyme activity.
Fulltext The Garlic Tree of Borneo, Scorodocarpus borneensis (Baill.) Becc. (Olacaceae): Potential Utilization in Pharmaceutical, Nutraceutical, and Functional Cosmetic Industries

Wiart C, Shorna AA, Rahmatullah M, Nissapatorn V, Seelan JSS, Rahman H, et al.

Molecules, 2023 Jul 28;28(15).
PMID: 37570687 DOI: 10.3390/molecules28155717

Scorodocarpus borneensis (Baill.) Becc. is attracting increased attention as a potential commercial medicinal plant product in Southeast Asia. This review summarizes the current knowledge on the taxonomy, habitat, distribution, medicinal uses, natural products, pharmacology, toxicology, and potential utilization of S. borneesis in the pharmaceutical/nutraceutical/functional cosmetic industries. All data in this review were compiled from Google Scholar, PubMed, Science Direct, Web of Science, ChemSpider, PubChem, and a library search from 1866 to 2022. A total of 33 natural products have been identified, of which 11 were organosulfur compounds. The main organosulfur compound in the seeds is bis-(methylthiomethyl)disulfide, which inhibited the growth of a broad spectrum of bacteria and fungi, T-lymphoblastic leukemia cells, as well as platelet aggregation. Organic extracts evoked anti-microbial, cytotoxic, anti-free radical, and termiticidal effects. S. borneensis and its natural products have important and potentially patentable pharmacological properties. In particular, the seeds have the potential to be used as a source of food preservatives, antiseptics, or termiticides. However, there is a need to establish acute and chronic toxicity, to examine in vivo pharmacological effects and to perform clinical studies.
Investigation of tribo-mechanical performance of alkali treated rice-husk and polypropylene-random-copolymer based biocomposites

Rabbani FA, Sulaiman M, Tabasum F, Yasin S, Iqbal T, Shahbaz M, et al.

Heliyon, 2023 Nov;9(11):e22028.
PMID: 38034731 DOI: 10.1016/j.heliyon.2023.e22028

This study was based on the experimental performance evaluation of a wood polymer composite (WPC) that was synthesized by incorporating untreated and treated rice husk (RH) fibers into a polypropylene random copolymer matrix. The submicron-scale RH fibers were alkali-treated to modify the surface and introduce new functional groups in the WPC. A compatibilizer (maleic anhydride) and a thermos-mechanical properties modifier (polypropylene grafted with 30 % glass fiber) were used in the WPC. The effects of untreated and treated RH on the WPC panels were studied using FESEM, FTIR, and microscope images. A pin-on-disk setup was used to investigate the bulk tribological properties of PPRC and WPC. The complex relationship between the friction coefficient of different loading of RH fibers in the WPC, as a function of sliding distance, was analyzed along with the temperature and morphology of the surface. It was observed that untreated RH acted as a friction modifier, while treated RH acted as a solid lubricant. Microhardness was calculated using the QCSM module on nanoindentation. It was found that untreated RH led to an increase in microhardness, while treated RH caused a decrease in hardness compared to PPRC.
In vitro and in vivo anti-inflammatory activities of columbin through the inhibition of cycloxygenase-2 and nitric oxide but not the suppression of NF-κB translocation

Ibrahim Abdelwahab S, Syaed Koko W, Mohamed Elhassan Taha M, Mohan S, Achoui M, Ameen Abdulla M, et al.

Eur J Pharmacol, 2012 Mar 5;678(1-3):61-70.
PMID: 22227329 DOI: 10.1016/j.ejphar.2011.12.024

Columbin, a diterpenoid furanolactone, was isolated purely for the first time from the plant species Tinspora bakis. The anti-inflammatory effects of columbin were studied in vitro, in silico and in vivo. The effect of columbin on nitric oxide was examined on lipopolysaccharide-interferon-gamma (LPS/IFN) induced RAW264.7 macrophages. In vitro and in silico cyclooxygenase-1 and cyclooxygenase-2 inhibitory activities of columbin using biochemical kit and molecular docking, respectively, were investigated. Mechanism of columbin in suppressing NF-kappaB-translocation was tested using Cellomics®NF-κB activation assay and ArrayScan Reader in LPS-stimulated RAW264.7 cells. Moreover, effects of columbin in vivo that were done on carrageenan-induced mice paw-oedema were tested. Lastly, the in vitro and in vivo toxicities of columbin were examined on human liver cells and mice, respectively. Treatment with columbin or N(ω)-nitro-l-arginine methyl ester (l-NAME) inhibited LPS/IFN-γ-induced NO production without affecting the viability of RAW264.7. Pre-treatment of stimulated cells with columbin did not inhibit the translocation of NF-κB to the nucleus in LPS-stimulated cells. COX-1 and COX-2 inhibitory activities of columbin were 63.7±6.4% and 18.8±1.5% inhibition at 100μM, respectively. Molecular docking study further helped in supporting the observed COX-2 selectivity. Whereby, the interaction of columbin with Tyr385 and Arg120 signifies its higher activity in COX-2, as Tyr385 was reported to be involved in the abstraction of hydrogen from C-13 of arachidonate, and Arg120 is critical for high affinity arachidonate binding. Additionally, columbin inhibited oedema formation in mice paw. Lastly, the compound was observed to be safe in vitro and in vivo. This study presents columbin as a potential anti-inflammatory drug.
Anti-inflammatory effect of zerumbone on acute and chronic inflammation models in mice

Sulaiman MR, Perimal EK, Akhtar MN, Mohamad AS, Khalid MH, Tasrip NA, et al.

Fitoterapia, 2010 Oct;81(7):855-8.
PMID: 20546845 DOI: 10.1016/j.fitote.2010.05.009

The anti-inflammatory activity of zerumbone (1), a natural cyclic sesquiterpene isolated from Zingiber zerumbet Smith was investigated using carrageenan-induced paw edema and cotton pellet-induced granuloma tissue formation test in mice. It was demonstrated that intraperitoneal administration of 1 at a dose of 5, 10, 50 and 100 mg/kg produced significant dose-dependent inhibition of paw edema induced by carrageenan. It was also demonstrated that 1 at similar doses significantly suppressed granulomatous tissue formation in cotton pellet-induced granuloma test.
Antinociceptive activity of a synthetic chalcone, flavokawin B on chemical and thermal models of nociception in mice

Mohamad AS, Akhtar MN, Zakaria ZA, Perimal EK, Khalid S, Mohd PA, et al.

Eur J Pharmacol, 2010 Nov 25;647(1-3):103-9.
PMID: 20826146 DOI: 10.1016/j.ejphar.2010.08.030

The present study examined the potential antinociceptive activity of flavokawin B (6'-hydroxy-2',4'-dimethoxychalcone), a synthetic chalcone using chemical- and thermal-induced nociception models in mice. It was demonstrated that flavokawin B (FKB; 0.3, 1, 3 and 10 mg/kg) administered via both oral (p.o.) and intraperitoneal (i.p.) routes produced significant and dose-dependent inhibition in the abdominal constrictions induced by acetic acid, with the i.p. route producing antinociception of approximately 7-fold more potent than the p.o. route. It was also demonstrated that FKB produced significant inhibition in the two phases of the formalin-induced paw licking test. In addition, the same treatment of flavokawin B (FKB) exhibited significant inhibition of the neurogenic nociceptive induced by intraplantar injections of glutamate and capsaicin. Likewise, this compound also induced a significant increase in the response latency period to thermal stimuli in the hot plate test and its antinociceptive effect was not related to muscle relaxant or sedative action. Moreover, the antinociception effect of the FKB in the formalin-induced paw licking test and the hot plate test was not affected by pretreatment of non-selective opioid receptor antagonist, naloxone. The present results indicate that FKB produced pronounced antinociception effect against both chemical and thermal models of pain in mice that exhibited both peripheral and central analgesic activity.
Antinociceptive, anti-inflammatory and antipyretic properties of Melastoma malabathricum leaves aqueous extract in experimental animals

Zakaria ZA, Raden Mohd Nor RN, Hanan Kumar G, Abdul Ghani ZD, Sulaiman MR, Rathna Devi G, et al.

Can J Physiol Pharmacol, 2006 Dec;84(12):1291-9.
PMID: 17487238

The present study was carried out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of the aqueous extract of Melastoma malabathricum leaves in experimental animals. The antinociceptive activity was measured using abdominal constriction, hot-plate, and formalin tests, whereas the anti-inflammatory and antipyretic activities were measured using carrageenan-induced paw edema and brewer's yeast-induced pyrexia tests, respectively. The extract, which was obtained after soaking the air-dried leaves in distilled water for 72 h and then preparing in concentrations of 10%, 50%, and 100% (v/v), was administered subcutaneously 30 min prior to subjection to the above mentioned assays. At all concentrations tested, the extract was found to exhibit significant (P < 0.05) antinociceptive, anti-inflammatory, and antipyretic activities in a concentration-independent manner. Our findings that the aqueous extract of M. malabathricum possesses antinociceptive, anti-inflammatory, and antipyretic activities supports previous claims on its traditional uses to treat various ailments.
Fulltext Relation between Density and Compressive Strength of Foamed Concrete

Othman R, Jaya RP, Muthusamy K, Sulaiman M, Duraisamy Y, Abdullah MMAB, et al.

Materials (Basel), 2021 May 31;14(11).
PMID: 34072721 DOI: 10.3390/ma14112967

This study aims to obtain the relationship between density and compressive strength of foamed concrete. Foamed concrete is a preferred building material due to the low density of its concrete. In foamed concrete, the compressive strength reduces with decreasing density. Generally, a denser foamed concrete produces higher compressive strength and lower volume of voids. In the present study, the tests were carried out in stages in order to investigate the effect of sand-cement ratio, water to cement ratio, foam dosage, and dilution ratio on workability, density, and compressive strength of the control foamed concrete specimen. Next, the test obtained the optimum content of processed spent bleaching earth (PSBE) as partial cement replacement in the foamed concrete. Based on the experimental results, the use of 1:1.5 cement to sand ratio for the mortar mix specified the best performance for density, workability, and 28-day compressive strength. Increasing the sand to cement ratio increased the density and compressive strength of the mortar specimen. In addition, in the production of control foamed concrete, increasing the foam dosage reduced the density and compressive strength of the control specimen. Similarly with the dilution ratio, the compressive strength of the control foamed concrete decreased with an increasing dilution ratio. The employment of PSBE significantly influenced the density and compressive strength of the foamed concrete. An increase in the percentage of PSBE reduced the density of the foamed concrete. The compressive strength of the foamed concrete that incorporated PSBE increased with increasing PSBE content up to 30% PSBE. In conclusion, the compressive strength of foamed concrete depends on its density. It was revealed that the use of 30% PSBE as a replacement for cement meets the desired density of 1600 kg/m3, with stability and consistency in workability, and it increases the compressive strength dramatically from 10 to 23 MPa as compared to the control specimen. Thus, it demonstrated that the positive effect of incorporation of PSBE in foamed concrete is linked to the pozzolanic effect whereby more calcium silicate hydrate (CSH) produces denser foamed concrete, which leads to higher strength, and it is less pore connected. In addition, the regression analysis shows strong correlation between density and compressive strength of the foamed concrete due to the R2 being closer to one. Thus, production of foamed concrete incorporating 30% PSBE might have potential for sustainable building materials.
Fulltext Antibacterial and Antifungal Terpenes from the Medicinal Angiosperms of Asia and the Pacific: Haystacks and Gold Needles

Wiart C, Kathirvalu G, Raju CS, Nissapatorn V, Rahmatullah M, Paul AK, et al.

Molecules, 2023 May 04;28(9).
PMID: 37175283 DOI: 10.3390/molecules28093873

This review identifies terpenes isolated from the medicinal Angiosperms of Asia and the Pacific with antibacterial and/or antifungal activities and analyses their distribution, molecular mass, solubility, and modes of action. All data in this review were compiled from Google Scholar, PubMed, Science Direct, Web of Science, ChemSpider, PubChem, and library searches from 1968 to 2022. About 300 antibacterial and/or antifungal terpenes were identified during this period. Terpenes with a MIC ≤ 2 µg/mL are mostly amphiphilic and active against Gram-positive bacteria, with a molecular mass ranging from about 150 to 550 g/mol, and a polar surface area around 20 Å². Carvacrol, celastrol, cuminol, dysoxyhainic acid I, ent-1β,14β-diacetoxy-7α-hydroxykaur-16-en-15-one, ergosterol-5,8-endoperoxide, geranylgeraniol, gossypol, 16α-hydroxy-cleroda-3,13 (14)Z-diene-15,16-olide, 7-hydroxycadalene, 17-hydroxyjolkinolide B, (20R)-3β-hydroxy-24,25,26,27-tetranor-5α cycloartan-23,21-olide, mansonone F, (+)-6,6'-methoxygossypol, polygodial, pristimerin, terpinen-4-ol, and α-terpineol are chemical frameworks that could be candidates for the further development of lead antibacterial or antifungal drugs.
Fulltext International Consensus for the Dosing of Corticosteroids in Childhood-Onset Systemic Lupus Erythematosus With Proliferative Lupus Nephritis

Chalhoub NE, Wenderfer SE, Levy DM, Rouster-Stevens K, Aggarwal A, Savani SI, et al.

Arthritis Rheumatol, 2022 Feb;74(2):263-273.
PMID: 34279063 DOI: 10.1002/art.41930

OBJECTIVE: To develop a standardized steroid dosing regimen (SSR) for physicians treating childhood-onset systemic lupus erythematosus (SLE) complicated by lupus nephritis (LN), using consensus formation methodology.
METHODS: Parameters influencing corticosteroid (CS) dosing were identified (step 1). Data from children with proliferative LN were used to generate patient profiles (step 2). Physicians rated changes in renal and extrarenal childhood-onset SLE activity between 2 consecutive visits and proposed CS dosing (step 3). The SSR was developed using patient profile ratings (step 4), with refinements achieved in a physician focus group (step 5). A second type of patient profile describing the course of childhood-onset SLE for ≥4 months since kidney biopsy was rated to validate the SSR-recommended oral and intravenous (IV) CS dosages (step 6). Patient profile adjudication was based on majority ratings for both renal and extrarenal disease courses, and consensus level was set at 80%.
RESULTS: Degree of proteinuria, estimated glomerular filtration rate, changes in renal and extrarenal disease activity, and time since kidney biopsy influenced CS dosing (steps 1 and 2). Considering these parameters in 5,056 patient profile ratings from 103 raters, and renal and extrarenal course definitions, CS dosing rules of the SSR were developed (steps 3-5). Validation of the SSR for up to 6 months post-kidney biopsy was achieved with 1,838 patient profile ratings from 60 raters who achieved consensus for oral and IV CS dosage in accordance with the SSR (step 6).
CONCLUSION: The SSR represents an international consensus on CS dosing for use in patients with childhood-onset SLE and proliferative LN. The SSR is anticipated to be used for clinical care and to standardize CS dosage during clinical trials.

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