MyMedR

Displaying publications 1 - 20 of 25 in total

Abstract:

Sort:

Selection of larvae of a laboratory colony of Culex pipiens fatigans Wiedemann for DDT-resistance

Thomas V

Med J Malaya, 1966 Mar;20(3):221-9.
PMID: 4380080
Matched MeSH terms: Drug Tolerance*
Fulltext Analysis of a low refractive index grating waveguide polarisation splitter based on resonant tunnelling

Yusoff, M.H.M., Hassan, H.A., Hashim, M.R., Abd-Rahman, M.K.

ASM Science Journal, 2008;2(2):139-148.
MyJurnal

The fabrication tolerance of a short and compact low refractive index grating waveguide polarisation splitter based on the principle of resonant tunnelling was analyzed in this study. The design utilised two grating waveguides with an intermediate conventional waveguide layer. The design and optimisation were conducted using the quasi 2-D effective index solver with global search algorithm. An optimum device operating at 1.55 μm wavelength was obtained at a length of 340 μm. The splitting ratios were calculated to be 36 dB and 15 dB, and the overall device transmission efficiencies, after considering the three-dimensional waveguide leakage loss, were estimated at 88% and 83% for tranverse magnetic and tranverse electric polarisation, respectively.

Matched MeSH terms: Drug Tolerance
The Potential of β Carbolin Alkaloids to Hinder Growth and Reverse Chloroquine Resistance in Plasmodium falciparum

Ibraheem ZO, Abdul Majid R, Mohd Noor S, Mohd Sidek H, Basir R

Iran J Parasitol, 2015 Oct-Dec;10(4):577-83.
PMID: 26811724

Nowadays, scourge of malaria as a fatalistic disease has increased due to emergence of drug resistance and tolerance among different strains of Plasmodium falciparum. Emergence of chloroquine (CQ) resistance has worsened the calamity as CQ is still considered the most efficient, safe and cost effective drug among other antimalarials. This urged the scientists to search for other alternatives or sensitizers that may be able to augment CQ action and reverse its resistance.

Matched MeSH terms: Drug Tolerance
Fulltext Dental Implants : Biomaterial, Biomechanical And Biological Considerations.

Isa, Z.M., Hobkirk, J.A.

Ann Dent, 2000;7(1):-.
MyJurnal

Currently many dental implant systems with varied and numerous components are available commercially, and with new implant systems and designs emerging, it is essential that the user understands that any system selected should be based on sound scientific principles and capable of osseoil!tegration. This has been defined in many different ways, with biomaterial, biological and biomechanical factors being the main considerations. The final restoration is based on both biological tissue and mechanical components. As the success of osseointegration is based on the clinical outcome, clinicians must ensure that the stresses that the superstructure, implant, and surrounding bone are subjected to are within the tolerable limits of the various components, even though the degree of tolerance has not yet been fully defined.

Matched MeSH terms: Drug Tolerance
Development of resazurin-based assay in 384-well format for high throughput whole cell screening of Trypanosoma brucei rhodesiense strain STIB 900 for the identification of potential anti-trypanosomal agents

Lim KT, Zahari Z, Amanah A, Zainuddin Z, Adenan MI

Exp Parasitol, 2016 Mar;162:49-56.
PMID: 26772786 DOI: 10.1016/j.exppara.2016.01.002

To accelerate the discovery of novel leads for the treatment of Human African Trypanosomiasis (HAT), it is necessary to have a simple, robust and cost-effective assay to identify positive hits by high throughput whole cell screening. Most of the fluorescence assay was made in black plate however in this study the HTS assay developed in 384-well format using clear plate and black plate, for comparison. The HTS assay developed is simple, sensitive, reliable and reproducible in both types of plates. Assay robustness and reproducibility were determined under the optimized conditions in 384-well plate was well tolerated in the HTS assay, including percentage of coefficient of variation (% CV) of 4.68% and 4.74% in clear and black 384-well plate, signal-to-background ratio (S/B) of 12.75 in clear 384-well plate and 12.07 in black 384-well plate, Z' factor of 0.79 and 0.82 in clear 384-well plate and black 384-well plate, respectively and final concentration of 0.30% dimethylsulfoxide (DMSO) in both types of plate. Drug sensitivity was found to be comparable to the reported anti-trypanosomal assay in 96-well format. The reproducibility and sensitivity of this assay make it compliant to automated liquid handler use in HTS applications.

Matched MeSH terms: Drug Tolerance
Effects of salt and heat pre-treatment factors on efficient regeneration in barley (Hordeum vulgare L.)

Haque M, Islam SMS, Subramaniam S

3 Biotech, 2017 May;7(1):63.
PMID: 28452013 DOI: 10.1007/s13205-017-0675-z

An efficient callus induction and plant regeneration system has been developed using salt and heat as pre-treatment factors for three barley genotypes viz. BB-3, BB-6 and BHL-18. Different concentrations of NaCl (1.5, 2.5, 3.5, 4.5, 5.5 and 6.5 g/L) were used and its effects were determined on the basis of the viability of callus (CV), plant regeneration (PR), relative growth rate (RGR) and tolerance index (TI). The BB-6 showed highest performance on tolerance based on CV (14.72%), PR (7.69%), RGR (0.91%) and TI (0.42%) at 6.5 g/L NaCl. Various NaCl concentrations displayed significantly differences at P

Matched MeSH terms: Drug Tolerance
Fulltext Patient-related barriers to cancer pain management – a prospective cross sectional study in a tertiary hospital

Choy, Y.C., Wan Nuruddin Shah, W.J., Wong, Y.M., Boey, C.Y., Noor Zuhaily, M.N., Kumutha, T., et al.

Journal of Surgical Academia, 2013;3(1):7-12.
MyJurnal

Effective management of cancer pain is often hampered by patients’ lack of knowledge regarding cancer pain management and other barriers related to ethnicity and religious beliefs. This cross sectional study was performed to determine the patient-related barriers to effective cancer pain management. One hundred patients receiving cancer pain management were studied. Inclusion criteria were: patients over the age of 18 years, able to communicate, with known diagnosis of cancer, experiencing persistent pain for the past two weeks. A modified version of the Barriers Questionnaire II (BQ-II) was used and a modified Brief Pain Inventory was used to assess the pain profile. Barriers such as, patient’s attitude and beliefs, communication skills and fear of side effects of pain medication were determined, given a score and the summation was recorded as the total patient related barriers score. Overall, 85% of respondents achieved more than 40% pain relief and the 72 of 100 patients reported low patient related barrier scores of 6 or less. Nevertheless, the main patient related barriers were: fear of tolerance to opioids (51%), ethnicity (p=0.003) and religious beliefs (p=0.002) which constituted the major components of the patient-related barriers score. Ethnicity and religious beliefs had significant influence on patient-related barriers score suggesting the need of further investigation into this area. In order to achieve a comprehensive view, other barriers to effective cancer pain management such as those related to the health systems and healthcare providers need to be assessed together.

Matched MeSH terms: Drug Tolerance
Fulltext The Effect of Tropical Environment on Fatigue Failure in Royal Malaysian Airforce (RMAF) Aircraft Structure and Operational Readiness

Venugopal A, Mohammad R, Koslan MFS, Sayd Bakar SR, Ali A

Materials (Basel), 2021 May 06;14(9).
PMID: 34066461 DOI: 10.3390/ma14092414

The environmental condition in which the Royal Malaysian Airforce is currently operating its aircraft is prone to corrosion. This is due to the high relative humidity and temperature. With most of its aircraft being in the legacy aircraft era, the aircraft's main construction consists of the aluminium 2024 material. However, this material is prone to corrosion, thus reducing fatigue life and leading to fatigue failure. Using the concept of either Safe Life or Damage Tolerance as its fatigue design philosophy, the RMAF adopts the Aircraft Structure Integrity Program (ASIP) to monitor its structural integrity. With the current problem of not having the structural limitation on corrosion-damaged structure, the RMAF has embarked on its fatigue testing method. Finite Element (FE) studies and flight tests were conducted, and the outcome is summarized. The conclusion is that the longeron tested on the aircraft can withstand the operational load, and its yield strength is below the ultimate yield strength of the material. These research outcomes will also enhance the ASIP for other aircraft platforms in the RMAF fleet for its structure life assessment or service life extension program.

Matched MeSH terms: Drug Tolerance
Effects of sublethal concentrations of dieldrin on Culex pipiens fatigans

Thomas V

Med J Malaysia, 1973 Mar;27(3):225-30.
PMID: 4268931
Matched MeSH terms: Drug Tolerance
Fulltext Alternative pain management via endocannabinoids in the time of the opioid epidemic: Peripheral neuromodulation and pharmacological interventions

Lee MT, Mackie K, Chiou LC

Br J Pharmacol, 2023 Apr;180(7):894-909.
PMID: 34877650 DOI: 10.1111/bph.15771

The use of opioids in pain management is hampered by the emergence of analgesic tolerance, which leads to increased dosing and side effects, both of which have contributed to the opioid epidemic. One promising potential approach to limit opioid analgesic tolerance is activating the endocannabinoid system in the CNS, via activation of CB1 receptors in the descending pain inhibitory pathway. In this review, we first discuss preclinical and clinical evidence revealing the potential of pharmacological activation of CB1 receptors in modulating opioid tolerance, including activation by phytocannabinoids, synthetic CB1 receptor agonists, endocannabinoid degradation enzyme inhibitors, and recently discovered positive allosteric modulators of CB1 receptors. On the other hand, as non-pharmacological pain relief is advocated by the US-NIH to combat the opioid epidemic, we also discuss contributions of peripheral neuromodulation, involving the electrostimulation of peripheral nerves, in addressing chronic pain and opioid tolerance. The involvement of supraspinal endocannabinoid systems in peripheral neuromodulation-induced analgesia is also discussed. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.

Matched MeSH terms: Drug Tolerance
Median Nerve Stimulation as a Nonpharmacological Approach to Bypass Analgesic Tolerance to Morphine: A Proof-of-Concept Study in Mice

Lee MT, Chen YH, Mackie K, Chiou LC

J Pain, 2021 03;22(3):300-312.
PMID: 33069869 DOI: 10.1016/j.jpain.2020.09.003

Analgesic tolerance to opioids contributes to the opioid crisis by increasing the quantity of opioids prescribed and consumed. Thus, there is a need to develop non-opioid-based pain-relieving regimens as well as strategies to circumvent opioid tolerance. Previously, we revealed a non-opioid analgesic mechanism induced by median nerve electrostimulation at the overlaying PC6 (Neiguan) acupoint (MNS-PC6). Here, we further examined the efficacy of MNS-PC6 in morphine-tolerant mice with neuropathic pain induced by chronic constriction injury (CCI) of the sciatic nerve. Daily treatments of MNS-PC6 (2 Hz, 2 mA), but not electrostimulation at a nonmedian nerve-innervated location, for a week post-CCI induction significantly suppressed established mechanical allodynia in CCI-mice in an orexin-1 (OX1) and cannabinoid-1 (CB1) receptor-dependent fashion. This antiallodynic effect induced by repeated MNS-PC6 was comparable to that induced by repeated gabapentin (50 mg/kg, i.p.) or single morphine (10 mg/kg, i.p.) treatments, but without tolerance, unlike repeated morphine-induced analgesia. Furthermore, single and repeated MNS-PC6 treatments remained fully effective in morphine-tolerant CCI-mice, also in an OX1 and CB1 receptor-dependent fashion. In CCI-mice receiving escalating doses of morphine for 21 days (10, 20 and 50 mg/kg), single and repeated MNS-PC6 treatments remained fully effective. Therefore, repeated MNS-PC6 treatments induce analgesia without tolerance, and retain efficacy in opioid-tolerant mice via a mechanism that involves OX1 and CB1 receptors. This study suggests that MNS-PC6 is an alternative pain management strategy that maybe useful for combatting the opioid epidemic, and opioid-tolerant patients receiving palliative care. PERSPECTIVE: Median nerve stimulation relieves neuropathic pain in mice without tolerance and retains efficacy even in mice with analgesic tolerance to escalating doses of morphine, via an opioid-independent, orexin-endocannabinoid-mediated mechanism. This study provides a proof of concept for utilizing peripheral nerve stimulating devices for pain management in opioid-tolerant patients.

Matched MeSH terms: Drug Tolerance*
Betel-quid dependence domains and syndrome associated with betel-quid ingredients among chewers: an Asian multi-country evidence

Lee CH, Chiang SL, Ko AM, Hua CH, Tsai MH, Warnakulasuriya S, et al.

Addiction, 2014 Jul;109(7):1194-204.
PMID: 24650227 DOI: 10.1111/add.12530

Betel-quid (BQ) contains biologically psychoactive ingredients; however, data are limited concerning the symptoms and syndrome of BQ dependence among chewers. The aims of this study were to evaluate the ingredients-associated BQ dependence syndrome and country-specific chewing features and behaviour for BQ dependence among chewers from six Asian communities.

Matched MeSH terms: Drug Tolerance
Fulltext Comparison of Pain Tolerance between Opioid Dependent Patients on Methadone Maintenance Therapy (MMT) and Opioid Naive Individuals

Zahari Z, Lee CS, Ibrahim MA, Musa N, Mohd Yasin MA, Lee YY, et al.

J Pharm Pharm Sci, 2016;19(1):127-36.
PMID: 27096697 DOI: 10.18433/J3NS49

PURPOSE: This study compared pain sensitivity among opioid dependent patients on methadone maintenance therapy (MMT) and opioid naive subjects.
METHODS: The three hundred participants comprised 152 opioid naive subjects and 148 opioid dependent patients. Opioid naive subjects had not taken any opioids including morphine and methadone to their best knowledge and were presumed so after two consecutive negative urine screenings for drugs. All opioid dependent patients were stabilized in treatment, defined as having been enrolled in the program for more than one month with no change of methadone dosage over the past one month. Excluded from the study were individuals with chronic or ongoing acute pain and individuals with a history of analgesics ingestion within 3 d before the cold pressor test (CPT). Pain tolerance to CPT was evaluated at 0 h, and at 2, 4, 8, 12, and 24 h post-methadone dose.
RESULTS: Patients exhibited a significantly shorter mean pain tolerance time of 34.17 s (95% CI 24.86, 43.49) versus 61.36 (52.23, 70.48) [p < 0.001] compared with opioid naive subjects. Time-dependent mean pain tolerance was also significantly different when naive subjects were compared to patients (p = 0.016).
CONCLUSIONS: This study revealed hyperalgesia amongst patients on MMT, as manifested by their quicker hand withdrawal. The complaints of pain in this population should not be underestimated and the pain should be evaluated seriously and managed aggressively.

Matched MeSH terms: Drug Tolerance
Fulltext Tolerance of daily single compared to space dose of Merital

Haq SM, Buhrich N

Med J Malaysia, 1980 Jun;34(4):358-62.
PMID: 7219263

Merital is a recently introduced antidepressant agent which is structurally unrelated to the traditional antidepressant agents and which is reported to have minimal side effects. This study aimed to establish the olerance of a single compared to a spaced dose .schedule of Merital. It was found that a single morrung dose of Merital 100 mgs compared to a similar dose of the drug given in two divided doses did not appreciably increase the frequency or severity of side effects.

Matched MeSH terms: Drug Tolerance
Fulltext Extent and patterns of drug abuse among children in Malaysia

Navaratnam V, Aun LB, Spencer CP

Bull Narc, 1979 Jul-Dec;31(3-4):59-68.
PMID: 44684

A field survey, based on a representative sample of children aged 12 to 16 years was carried out in three different areas of Malaysia. The data derived from the study have revealed that 10.5 per cent of them used drugs for non-medical reasons. Drug use was more common among boys (11.9 per cent) than girls (8.6 per cent). The highest frequency of drug was found in the youngest group--12-year-old children (13.5 per cent). The use of barbiturate and/or non-barbiturate sedatives (5.5 per cent) ranked first. This was followed in descending order by tranquillizers (4.5 per cent), simultants/amphetamines (3.9 per cent), heroin (3.6 per cent), morphine and/or opium (3.9 per cent), the hallucinogens (3.1 per cent) and cannabis (2.7 per cent).

Matched MeSH terms: Drug Tolerance
"Catapres in the management of hypertension"

Singh N, Menon V

Med J Malaysia, 1975 Mar;30(3):209-13.
PMID: 1160681
Matched MeSH terms: Drug Tolerance
Fulltext Characterisation of the probiotic qualities exhibited by lactobacilli strains isolated from the anogenital tract

Choo, Sulin, Chew, Boon How, Amilia Afzan Mohd. Jamil, Chew, Shu Yih, Hadiza Umar Meleh, Leslie Than Thian Lung

Malaysian Journal of Medicine and Health Sciences, 2019;15(1):37-45.
MyJurnal

Lactobacilli are well-documented probiotics that exert health benefits on their host. They exhibit characteristics that make them potential alternative treatments to address the antimicrobial resistance conundrum and diseases. Their mechanism of action varies with strain and species. Five lactobacilli strains previously isolated from the anogenital region were subjected to several assessments highlighted in the FAO/WHO document, ‘Guidelines for the Evaluation of Probiotics in Food’ to determine its suitability as potential probiotics. Methods: The five lactobacilli strains were subcultured onto Man de Rogosa agar (MRS). Their ability to auto- and co-aggregate was determined spectrophotometrically. Simultaneously, the cell surface hydrophobic properties of these strains towards xylene and toluene were evaluated using the microbial adhesion to hydrocarbon (MATH) test. The lactobacilli strains were also tested for their ability to withstand acid, bile and spermicide to determine their level of tolerance. Results: Lact. reuteri 29A, L. delbrueckii 45E and L. reuteri 29B exhibited the highest degree of auto- and co-aggregation properties. These lactobacilli strains also demonstrated high cell surface hydrophobicity, with the exception of L. delbrueckii 45E. Further tests to evaluate the isolated lactobacilli tolerance identified L. reuteri 29B as the most tolerant strain towards low pH (pH 2.5 for 4 h), high bile concentration (0.5% for 4 h) and high spermicides concentration (up to 10%). Conclusion: Out of the five lactobacilli strains which possessed high antimicrobial activities, L. reuteri 29B portrayed the best probiotic qualities with good auto- and co-aggregation abilities and high tolerance against acid, bile and spermicide.

Matched MeSH terms: Drug Tolerance
Suprofen: its usefulness in the control of pain following surgical removal of impacted wisdom tooth

Awang MN, Boon LC, Nor GM

Indian J Med Sci, 1990 Aug;44(8):205-8.
PMID: 2262207

The results of the present investigation have shown the usefulness of suprofen in the control of pain following surgical removal of impacted wisdom tooth. The regime of 200 mg. q.d.s. orally, was shown to be satisfactory in the control of postoperative pain. Pain was rapidly controlled by the 1st hour after ingestion and subsequently maintained at a low profile until is was completely abolished by the 8th hour of the postoperative period.

Matched MeSH terms: Drug Tolerance
Fulltext The combination of mitragynine and morphine prevents the development of morphine tolerance in mice

Fakurazi S, Rahman SA, Hidayat MT, Ithnin H, Moklas MA, Arulselvan P

Molecules, 2013 Jan 04;18(1):666-81.
PMID: 23292329 DOI: 10.3390/molecules18010666

Mitragynine (MG) is the major active alkaloid found in Mitragyna speciosa Korth. In the present study, we investigated the enhancement of analgesic action of MG when combined with morphine and the effect of the combination on the development of tolerance towards morphine. Mice were administered intraperitoneally with a dose of MG (15 and 25 mg/kg b.wt) combined with morphine (5 mg/kg b.wt) respectively for 9 days. The antinociceptive effect was evaluated by a hot plate test. The protein expression of cyclic adenosine monophosphate (cAMP) and cAMP response element binding (CREB) was analyzed by immunoblot. Toxicological parameters especially liver and kidney function tests were assessed after the combination treatment with MG and morphine. The concurrent administration of MG and morphine showed significant (p < 0.05) increase in latency time when compared to morphine alone group and the outstanding analgesic effects in the combination regimens were maintained until day 9. For the protein expression, there was a significant increment of cAMP and CREB levels (p < 0.05) in group treated with 5 mg/kg morphine but there was no significant change of these protein expressions when MG was combined with morphine. There was a significant changes in toxicological parameters of various treated groups. The combination treatment of MG and morphine effectively reduce the tolerance due to the chronic administration of morphine.

Matched MeSH terms: Drug Tolerance*
Physical factors affecting the production of organic solvent-tolerant protease by Pseudomonas aeruginosa strain K

Rahman RN, Geok LP, Basri M, Salleh AB

Bioresour Technol, 2005 Mar;96(4):429-36.
PMID: 15491823

The physical factors affecting the production of an organic solvent-tolerant protease from Pseudomonas aeruginosa strain K was investigated. Growth and protease production were detected from 37 to 45 degrees C with 37 degrees C being the optimum temperature for P. aeruginosa. Maximum enzyme activity was achieved at static conditions with 4.0% (v/v) inoculum. Shifting the culture from stationary to shaking condition decreased the protease production (6.0-10.0% v/v). Extracellular organic solvent-tolerant protease was detected over a broad pH range from 6.0 to 9.0. However, the highest yield of protease was observed at pH 7.0. Neutral media increased the protease production compared to acidic or alkaline media.

Matched MeSH terms: Drug Tolerance

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links