Asma Hassan

Tualang honey supplement improves memory performance and hippocampal morphology in stressed ovariectomized rats

Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed sham-operated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17β-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rats.

Chitosan dermal substitute and chitosan skin substitute contribute to accelerated full-thickness wound healing in irradiated rats.

Wounds with full-thickness skin loss are commonly managed by skin grafting. In the absence of a graft, reepithelialization is imperfect and leads to increased scar formation. Biomaterials can alter wound healing so that it produces more regenerative tissue and fewer scars. This current study use the new chitosan based biomaterial in full-thickness wound with impaired healing on rat model. Wounds were evaluated after being treated with a chitosan dermal substitute, a chitosan skin substitute, or duoderm CGF. Wounds treated with the chitosan skin substitute showed the most re-epithelialization (33.2 ± 2.8%), longest epithelial tongue (1.62 ± 0.13 mm), and shortest migratory tongue distance (7.11 ± 0.25 mm). The scar size of wounds treated with the chitosan dermal substitute (0.13 ± 0.02 cm) and chitosan skin substitute (0.16 ± 0.05 cm) were significantly decreased (P < 0.05) compared with duoderm (0.45 ± 0.11 cm). Human leukocyte antigen (HLA) expression on days 7, 14, and 21 revealed the presence of human hair follicle stem cells and fibroblasts that were incorporated into and surviving in the irradiated wound. We have proven that a chitosan dermal substitute and chitosan skin substitute are suitable for wound healing in full-thickness wounds that are impaired due to radiation.

Enhancement of BDNF concentration and restoration of the hypothalamic-pituitary-adrenal axis accompany reduced depressive-like behaviour in stressed ovariectomised rats treated with either Tualang honey or estrogen.

A possible interaction between glucocorticoids and estrogen-induced increases in brain-derived-neurotrophic factor (BDNF) expression in enhancing depressive-like behaviour has been documented. Here we evaluated the effects of Tualang honey, a phytoestrogen, and 17β-estradiol (E2) on the depressive-like behaviour, stress hormones, and BDNF concentration in stressed ovariectomised (OVX) rats. The animals were divided into six groups: (i) nonstressed sham-operated control, (ii) stressed sham-operated control, (iii) nonstressed OVX, (iv) stressed OVX, (v) stressed OVX treated with E2 (20 μg daily, sc), and (vi) stressed OVX treated with Tualang honey (0.2 g/kg body weight daily, orally). Two months after surgery, the animals were subjected to social instability stress procedure followed by forced swimming test. Struggling time, immobility time, and swimming time were scored. Serum adrenocorticotropic hormone (ACTH) and corticosterone levels, and the BDNF concentration were determined using commercially available ELISA kits. Stressed OVX rats displayed increased depressive-like behaviour with significantly increased serum ACTH and corticosterone levels, while the BDNF concentration was significantly decreased compared to other experimental groups. These changes were notably reversed by both E2 and Tualang honey. In conclusion, both Tualang honey and E2 mediate antidepressive-like effects in stressed OVX rats, possibly acting via restoration of hypothalamic-pituitary-adrenal axis and enhancement of the BDNF concentration.

Mood and memory function in ovariectomised rats exposed to social instability stress.

This study aims to compare the effects of social instability stress on memory and anxiety- and depressive-like behaviour between sham-operated controls and ovariectomised (OVX) rats. Forty adult female Sprague-Dawley rats (8 weeks old) were randomly divided into four groups, (n = 10 per group). These were non-stressed sham-operated control rats, stressed sham-operated control rats, non-stressed OVX rats, and stressed OVX rats. The rats were subjected to social instability stress procedure for 15 days. Novel object recognition, open field, and forced swim tests were conducted after the stress procedure. Serum estradiol, ACTH and corticosterone levels were measured using commercially available ELISA kits. Lower serum estradiol level and uterine weight with higher weight gain were observed in OVX rats compared to sham-operated controls. Serum ACTH, and corticosterone levels were higher in stressed compared to non-stressed groups. Memory deficit and anxiety- and depressive-like behaviour were significantly increased in stressed compared to non-stressed OVX rats but these changes were not seen in sham-operated controls. These results suggest that the high circulating corticosterone acts synergistically with low circulating estradiol to exert negative effects on mood and memory function.

Potential Role of Honey in Learning and Memory

The composition and physicochemical properties of honey are variable depending on its floral source and often named according to the geographical location. The potential medicinal benefits of Tualang honey, a multifloral jungle honey found in Malaysia, have recently been attracting attention because of its reported beneficial effects in various diseases. This paper reviews the effects of honey, particularly Tualang honey, on learning and memory. Information regarding the effects of Tualang honey on learning and memory in human as well as animal models is gleaned to hypothesize its underlying mechanisms. These studies show that Tualang honey improves morphology of memory-related brain areas, reduces brain oxidative stress, increases brain-derived neurotrophic factor (BDNF) and acetylcholine (ACh) concentrations, and reduces acetylcholinesterase (AChE) in the brain homogenates. Its anti-inflammatory roles in reducing inflammatory trigger and microglial activation have yet to be investigated. It is hypothesized that the improvement in learning and memory following Tualang honey supplementation is due to the significant improvement in brain morphology and enhancement of brain cholinergic system secondary to reduction in brain oxidative damage and/or upregulation of BDNF concentration. Further studies are imperative to elucidate the molecular mechanism of actions.

Interparietal Bone Variations in Accordance with their Ossification Centres in Human Skulls

El segmento interparietal superior de la porcion escamosa del hueso occipital es de origen membranoso y la parte inferior supraoccipital se desarrolla en el cartilago. De acuerdo con la literatura disponible, el segmento interparietal se osifica a partir de 2 a3 pares de centros y cada uno de estos centros cuenta con 2 nucleos. El hueso interparietal se forma debido a la falta de fusion de estos centros y / o sus nucleos. Muchas variaciones de hueso interparietal han sido reportados por investigadores. En el presente estudio, de 25 craneos humanos estudiados, seis craneos presentaban algunas variaciones interesantes de huesos interparietales. Cuatro huesos interparietales fueron encontrados en un craneo, dos huesos interparietales en un craneo y cuatro craneos presentaban un solo hueso interparietal (Os inca) en el lambda. Ademas, de los huesos interparietales, en tres craneos se observaron huesos suturales. Estas variaciones estaban en relacion con los centros de osificacion de la parte membranosa del hueso occipital. Por su ubicacion y forma, se concluyo que los huesos se formaron debido a la falta de fusion entre si de los nucleos de los centros del tercer par de osificacion, con otros opuestos y con los centros del segundo par. Se concluye, ademas, que estos casos de huesos interparietales eran diferentes de lo que se habia informado anteriormente por otros investigadores y esto nos impulso al estudio, el cual puede ser util para anatomistas, antropologos, radiologos y neurocirujanos.

Empowering students’ minds through a cognitive load theory-based lecture model: A metacognitive approach

ABSTRACT Lecturing is widely considered to be a passive, teacher-centred teaching method that fails to foster learning, yet it remains the most feasible method of teaching among higher institutions. Some modern lectures, aligned with recommendations from published guidelines on effective lecturing, are less didactic and more interactive than others, but little is known about converting the classical knowledge-transfer process of lecturing to actual learning. We introduce a cognitive load theory-based lecture guideline that adopts various types of empirically proven strategies to manage learners’ mental loads during lectures. We conducted a randomised controlled trial to evaluate its effectiveness by determining the between-group difference in cognitive load level, self-perceived learning, knowledge acquisition and knowledge retention. This study discusses the practical application of the guideline and several examples of the principles.

Protective Effects of Tualang Honey against Oxidative Stress and Anxiety-Like Behaviour in Stressed Ovariectomized Rats.

The present study aims to evaluate the antioxidant and anxiolytic-like effect of Tualang honey in stressed ovariectomized (OVX) rats. The animals were divided into; (i) nonstressed sham-operated control rats, (ii) sham-operated control rats exposed to stress, (iii) nonstressed OVX rats, (iv) OVX rats exposed to stress, (v) OVX rats exposed to stress and treated with 17 β-oestradiol (E2) (20 μg daily, sc), and (vi) OVX rats exposed to stress and treated with Tualang honey (0.2 g/kg body weight, orally). The open field test was used to evaluate the anxiety-like behaviour and ELISA kits were used to measure oxidant/antioxidant status of the brain homogenates. The result showed that anxiety-like behavior was significantly increased in stressed OVX compared to other groups, and administering either E2 or Tualang honey significantly decreased anxiety-like behaviour in stressed OVX rats. The levels of malondialdehyde (MDA) and protein carbonyl (PCO) were significantly decreased while the levels/activities of superoxide dismutase (SOD), glutathione S-transferases (GST), glutathione peroxidase (GPx), and glutathione reductase (GR) were significantly increased in the brain homogenates of treated stressed OVX groups compared to untreated stressed OVX. In conclusion, Tualang honey has protective effects against brain oxidative stress and may be useful alternative anxiolytic agent especially for postmenopausal women.

The Teacher Behavior Inventory: validation of teacher behavior in an interactive lecture environment

Abstract Students’ rating of teacher behaviors provides valuable information on teaching improvement and instructional quality. Unfortunately, there is a lack of new validated instruments for measuring teacher behaviors. The Teacher Behaviors Inventory is an old inventory that was initially developed to measure teaching behaviors as regards lecture-based instructions, which is effected through the use of low-inference items. The aim of this study was to assess its continued suitability in the present educational setting by examining its construct validity and internal consistency through the lens of one lecturer’s teaching behaviors, as rated by 527 students after six interactive lectures. The variables evaluated, as mentioned above, were achieved after an items removal process, which resulted in a 32-item version. Apart from being valid and reliable, this condensed version allows for immediate assessment of teaching behaviors after an instruction session as the rating procedure is now more straightforward and less time-consuming, and also enables a reduction in rating errors. Therefore, the 32-item format serves as a practical diagnostic feedback tool in the present educational arena, permitting a longitudinal teaching behavior assessment to enhance teachers’ professional development.