MyMedR

Displaying all 7 publications

Abstract:

Sort:

Fulltext Formulation, Characterization and Cytotoxicity Effects of Novel Thymoquinone-PLGA-PF68 Nanoparticles

Noor NS, Kaus NHM, Szewczuk MR, Hamid SBS

Int J Mol Sci, 2021 Aug 30;22(17).
PMID: 34502328 DOI: 10.3390/ijms22179420

Thymoquinone has anti-cancer properties. However, its application for clinical use is limited due to its volatile characteristics. The current study aims to develop a polymeric nanoformulation with PLGA-PEG and Pluronics F68 as encapsulants to conserve thymoquinone's (TQ) biological activity before reaching the target sites. Synthesis of nanoparticles was successfully completed by encapsulating TQ with polymeric poly (D, L-lactide-co-glycolide)-block-poly (ethylene glycol) and Pluronics F68 (TQ-PLGA-PF68) using an emulsion-solvent evaporation technique. The size and encapsulation efficiency of TQ-PLGA-PF68 nanoparticles were 76.92 ± 27.38 nm and 94%, respectively. TQ released from these encapsulants showed a biphasic released pattern. Cytotoxicity activity showed that tamoxifen-resistant (TamR) MCF-7 breast cancer cells required a higher concentration of TQ-PLGA-PF68 nanoparticles than the parental MCF-7 cells to achieve IC50 (p < 0.05). The other two resistant subtypes (TamR UACC732 inflammatory breast carcinoma and paclitaxel-resistant (PacR) MDA-MB 231 triple-negative breast cell line) required a lower concentration of TQ-PLGA-PF68 nanoparticles compared to their respective parental cell lines (p < 0.05). These findings suggest that TQ encapsulation with PLGA-PEG and Pluronics F68 is a promising anti-cancer agent in mitigating breast cancer resistance to chemotherapeutics. In future studies, the anti-cancer activity of TQ-PLGA-PF68 with the standard chemotherapeutic drugs used for breast cancer treatment is recommended.
Fulltext Clinacanthus nutans L Extracts Reduce the Serum Tumor Necrosis Factor-α, Malondialdehyde, and Interleukin-6 Levels and Improve the Langerhans Islet Area in Diabetic Rat Models

Mustika A, Fatimah N, Safitri I, Susanti N, Noor NS

Clin Med Insights Endocrinol Diabetes, 2023;16:11795514231196462.
PMID: 37694133 DOI: 10.1177/11795514231196462

BACKGROUND: Diabetes mellitus-induced hyperglycemia increases oxidative stress and inflammatory cytokine production, which play a significant role in the damage and apoptosis of pancreatic β cells. Therefore, the administration of medications that can reduce oxidative stress and inflammation plays an important role in diabetes treatment.
OBJECTIVE: To probe the Clinacanthus nutans leaf extract effect on oxidative stress and inflammatory markers and the Langerhans islet area in diabetic rat models.
DESIGN: An experimental laboratory in the animal model.
METHODS: Twenty-five diabetic rat models were randomly assigned into 5 clusters. Clusters 1, 2, and 3 were administered with C. nutans leaf extract in aqueous suspension with vehicle 1% Na-CMC at 75 mg/kg body weight (BW), 150 mg/kg BW, and 300 mg/kg BW, respectively. Cluster 4 was diabetic control rats administered with metformin at a 21 mg/rat dose. Cluster 5 was a control diabetic rat only administered with 1% Na-CMC suspension. Treatment was administered orally for 14 days. On the 15th day, the rats were sacrificed to obtain blood samples and pancreatic tissues. Serum interleukin (IL)-6, malondialdehyde (MDA), and tumor necrosis factor (TNF-α) were measured using the enzyme-linked immunosorbent assay (ELISA) method. Histopathological examination was performed by counting the Langerhans islet areas.
RESULTS: The average IL-6, MDA, and TNF-α levels declined in the cluster receiving C. nutans extract and were significantly different from the untreated cluster (P
Fulltext Geographical pattern and environmental correlates of regional-scale general flowering in Peninsular Malaysia

Numata S, Yasuda M, Suzuki RO, Hosaka T, Noor NS, Fletcher CD, et al.

PLoS One, 2013;8(11):e79095.
PMID: 24260159 DOI: 10.1371/journal.pone.0079095

In South-East Asian dipterocarp forests, many trees synchronize their reproduction at the community level, but irregularly, in a phenomenon known as general flowering (GF). Several proximate cues have been proposed as triggers for the synchronization of Southeast Asian GF, but the debate continues, as many studies have not considered geographical variation in climate and flora. We hypothesized that the spatial pattern of GF forests is explained by previously proposed climatic cues if there are common cues for GF among regions. During the study, GF episodes occurred every year, but the spatial occurrence varied considerably from just a few forests to the whole of Peninsular Malaysia. In 2001, 2002 and 2005, minor and major GF occurred widely throughout Peninsular Malaysia (GF2001, GF2002, and GF2005), and the geographical patterns of GF varied between the episodes. In the three regional-scale GF episodes, most major events occurred in regions where prolonged drought (PD) had been recorded prior, and significant associations between GF scores and PD were found in GF2001 and GF2002. However, the frequency of PD was higher than that of GF throughout the peninsula. In contrast, low temperature (LT) was observed during the study period only before GF2002 and GF2005, but there was no clear spatial relationship between GF and LT in the regional-scale episodes. There was also no evidence that last GF condition influenced the magnitude of GF. Thus, our results suggest that PD would be essential to trigger regional-scale GF in the peninsula, but also that PD does not fully explain the spatial and temporal patterns of GF. The coarse relationships between GF and the proposed climatic cues may be due to the geographical variation in proximate cues for GF, and the climatic and floristic geographical variations should be considered to understand the proximate factors of GF.
Acrylic microspheres-based optosensor for visual detection of nitrite

Noor NS, Tan LL, Heng LY, Chong KF, Tajuddin SN

Food Chem, 2016 Sep 15;207:132-8.
PMID: 27080889 DOI: 10.1016/j.foodchem.2016.03.088

A new optosensor for visual quantitation of nitrite (NO2(-)) ion has been fabricated by physically immobilizing Safranine O (SO) reagent onto a self-adhesive poly(n-butyl acrylate) [poly(nBA)] microspheres matrix, which was synthesized via facile microemulsion UV lithography technique. Evaluation and optimization of the optical NO2(-) ion sensor was performed with a fiber optic reflectance spectrophotometer. Scanning electron micrograph showed well-shaped and smooth spherical morphology of the poly(nBA) microspheres with a narrow particles size distribution from 0.6μm up to 1.8μm. The uniform size distribution of the acrylic microspheres promoted homogeneity of the immobilized SO reagent molecules on the microspheres' surfaces, thereby enhanced the sensing response reproducibility (<5% RSD) with a linear range obtained from 10 to 100ppm NO2(-) ion. The micro-sized acrylic immobilization matrix demonstrated no significant barrier for diffusion of reactant and product, and served as a good solid state ion transport medium for reflectometric nitrite determination in food samples.
Fulltext Satellite-based characterization of climatic conditions before large-scale general flowering events in Peninsular Malaysia

Azmy MM, Hashim M, Numata S, Hosaka T, Noor NS, Fletcher C

Sci Rep, 2016 08 26;6:32329.
PMID: 27561887 DOI: 10.1038/srep32329

General flowering (GF) is a unique phenomenon wherein, at irregular intervals, taxonomically diverse trees in Southeast Asian dipterocarp forests synchronize their reproduction at the community level. Triggers of GF, including drought and low minimum temperatures a few months previously has been limitedly observed across large regional scales due to lack of meteorological stations. Here, we aim to identify the climatic conditions that trigger large-scale GF in Peninsular Malaysia using satellite sensors, Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS), to evaluate the climatic conditions of focal forests. We observed antecedent drought, low temperature and high photosynthetic radiation conditions before large-scale GF events, suggesting that large-scale GF events could be triggered by these factors. In contrast, we found higher-magnitude GF in forests where lower precipitation preceded large-scale GF events. GF magnitude was also negatively influenced by land surface temperature (LST) for a large-scale GF event. Therefore, we suggest that spatial extent of drought may be related to that of GF forests, and that the spatial pattern of LST may be related to that of GF occurrence. With significant new findings and other results that were consistent with previous research we clarified complicated environmental correlates with the GF phenomenon.
Three-dimensional surface area analyses of developing maxillary second premolar root apices for age estimation using CBCT images

Gohain M, Asif MK, Nambiar P, Mohd Noor NS, Hidayah Reduwan N, Ibrahim N

Leg Med (Tokyo), 2024 Feb;66:102391.
PMID: 38211402 DOI: 10.1016/j.legalmed.2024.102391

Three-dimensional surface area analyses of developing root apices for age estimation in children and young adults have shown promising results. The current study aimed to apply this three-dimensional method to develop a regression model for estimating age in Malaysian children aged 7 to 14 using developing maxillary second premolars. A training sample of 155 cone-beam computed tomography scans (83 Malays and 72 Chinese) was analysed, and the formula was subsequently validated on an independent sample of 92 cone-beam computed tomography scans (45 Malays and 47 Chinese). The results showed a strong correlation (r = 94 %) between the chronological age as a dependent variable and the predictor variables, including root surface area of the apex, sex, ethnicity, and root development status (open/closed apices). For this model, the predictor variables accounted for 88.4 % of the variation in age except sex and ethnicity. A mean absolute error value of 0.42 indicated that this model can be reliably used for Malaysian children. In conclusion, this study recognises the method of three-dimensional surface area analyses as a valuable tool for age estimation in forensic and clinical practice. Further studies are highly recommended to assess its effectiveness across different demographic groups.
Application of a new system for classifying root canal morphology in undergraduate teaching and clinical practice: a national survey in Malaysia

Ahmed HMA, Che Ab Aziz ZA, Azami NH, Farook MS, Khan AA, Mohd Noor NS, et al.

Int Endod J, 2020 Jun;53(6):871-879.
PMID: 32003029 DOI: 10.1111/iej.13271

AIM: To evaluate and compare the feedback of final year undergraduate dental students in eight Malaysian dental schools on the application of a new system for classifying root canal morphology in teaching and clinical practice.
METHODS: One PowerPoint presentation describing two classification systems for root canal morphology (Oral Surgery Oral Medicine Oral Pathology, 1974 38, 456 and its supplemental configurations, International Endodontic Journal 2017, 50, 761) was delivered to final year undergraduate dental students in eight dental schools in Malaysia by two presenters (each presented to four schools). To examine students' feedback on the utility of each system, printed questionnaires consisting of six questions (five multiple choice questions and one open-ended question) were distributed and collected after the lecture. The questionnaire was designed to compare the classification systems in terms of accuracy, practicability, understanding of root canal morphology and recommendation for use in pre-clinical and clinical courses. The exact test was used for statistical analysis, with the level of significance set at 0.05 (P = 0.05).
RESULTS: A total of 382 (out of 447) students participated giving a response rate of 86%. More than 90% of students reported that the new system was more accurate and more practical compared with the Vertucci system (P 0.05). The students' responses for all questions were almost similar for both presenters (P > 0.05).
CONCLUSIONS: The new system of International Endodontic Journal 2017, 50, 761 for classifying root and canal morphology was favoured by final year undergraduate dental students in Malaysia. The new system has the potential to be included in the undergraduate endodontic curriculum for teaching courses related to root and canal morphology.