Displaying publications 21 - 40 of 4455 in total

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  1. The effect of early-age food restriction on heat shock protein 70 response in heat-stressed female broiler chickens
    Zulkifli I, Che Norma MT, Israf DA, Omar AR
    Br Poult Sci, 2002 Mar;43(1):141-5.
    PMID: 12003331
    1. This study was conducted to determine the effect of early-age food restriction on heat shock protein (hsp) 70 synthesis in the brains of female broiler chickens exposed to high ambient temperatures. 2. Chicks were brooded for 3 weeks and then maintained at 24+/-1 degrees C. 3. On d 0, chicks were assigned to one of 4 feeding regimens; each regimen was applied to 4 cages of chicks. The regimens were: (1) ad libitum feeding (AL); (2) 80% food restriction at 4, 5 and 6 d of age (F80); (3) 60% food restriction at 4, 5, and 6 d of age (F60); and (4) 40% food restriction at 4, 5 and 6 d of age (F40). From d 35 to d 41, all chicks were subjected to 38+/-1 degrees C for 2 h/d. 4. One day following food restriction (d 7), hsp 70 expression in the brain samples of F60 and F40 chicks was augmented but not those fed AL and F80. 5. Prior to the heat challenge (d 35), all chicks had similar hsp 70 response. Irrespective of feeding regimen, there was a marked increase in hsp 70 expression after 4 d of heat treatment (d 38). Following 7 d of heat exposure (d 41), except for the F60 chicks, the augmented hsp 70 expression in the brains of AL, F80 and F40 birds was not maintained. 6. Enhancement of hsp 70 expression was noted in birds subjected to F60, but not AL, F80 or F40, throughout the period of heat exposure.
    Matched MeSH terms: Brain Chemistry/physiology*; Chickens/physiology*; Food Deprivation/physiology*
  2. Growth performance and immune response of two commercial broiler strains fed diets containing Lactobacillus cultures and oxytetracycline under heat stress conditions
    Zulkifli I, Abdulllah N, Azrin NM, Ho YW
    Br Poult Sci, 2000 Dec;41(5):593-7.
    PMID: 11201439
    1. Hubbard x Hubbard (HH) and Shaver x Shaver (SS) chicks given a dietary supplement of either 50 mg/kg oxytetracycline (OTC) or 1 g/kg Lactobacillus culture (LC) were exposed to 36 +/- 1 degrees C for 3 h daily from day (d) 21 to 42. 2. Prior to heat treatment, body weight (d 21) and weight gain (d 1 to d 21) of OTC and LC birds were greater than those fed the control diet. Chicks given LC had the best food efficiency followed by OTC and control birds during d 1 to d 21. Body weight (d 1 and d 21) and weight gain (d 1 to d 21) were greater for HH tlhan SS chicks. 3. After 3 weeks of heat exposure, birds receiving the LC diet had greater body weight and weight gain, higher food intake and lower food efficiency than OTC and control chicks. 4. Antibody production against Newcastle discase vaccine on d 21 was not affected by strain or diet. On d 42, while diet had negligible effect on this variable among the SS broilers, HH birds fed LC had higher antibody production than those on the control diet. 5. Neither strain nor diet had a significant effect on mortality.
    Matched MeSH terms: Chickens/physiology
  3. Effects of low-protein diets on acute phase proteins and heat shock protein 70 responses, and growth performance in broiler chickens under heat stress condition
    Zulkifli I, Akmal AF, Soleimani AF, Hossain MA, Awad EA
    Poult Sci, 2018 Apr 01;97(4):1306-1314.
    PMID: 29381776 DOI: 10.3382/ps/pex436
    A study with a 4 × 2 factorial arrangement was conducted to investigate the effects of 4 dietary protein levels and 2 environmental conditions on acute phase proteins (APP), brain heat shock protein (HSP) 70 density, and growth performance of broiler chickens. Day-old broiler chicks (Cobb 500) were fed isocaloric diets but with various levels of crude protein (CP), namely, (1) 21.0 and 19.0% CP in starter and finisher diets, respectively (control), (2) 19.5 and 17.5% CP in starter and finisher diets, respectively (Diet A), (3) 18.0 and 16.0% CP in starter and finisher diets, respectively (Diet B), and (4) 16.5 and 14.5% CP in starter and finisher diets, respectively (Diet C). Equal numbers of birds from each diet were subjected to either 23±1°C throughout or 33±1°C for 6 h per d from 22 to 35 d of age. From d 1 to 21, feed intake (FI) and weight gain (WG) decreased linearly (P = 0.021 and P = 0.009, respectively), as CP level was reduced. During the heat treatment period (d 22 to 35), there were significant (P = 0.04) diet × heat treatment interactions for FCR. Diet had no effect on FCR among the unheated birds, but the ratio increased linearly (P = 0.007) as dietary CP level decreased. Irrespective of ambient temperature, there was a significant linear decrease in FI (P = 0.032) and WG (P < 0.001) as dietary CP level decreased. Low-CP diets improved the survivability of heat-stressed broilers when compared to those fed control diets. Low-CP diets linearly decreased (P < 0.01) APP (ovotransferrin and alpha-acid glycoprotein) responses. Both APP and HSP 70 reactions were elevated following heat treatment. In conclusion, feeding broilers with low-CP diets adversely affect the growth performance of broilers under heat stress condition. However, low-CP diets were beneficial in improving the survivability. Because APP are involved in the restoration of homeostasis, the adverse effect of low-CP diet on the synthesis of these proteins could be of concern.
    Matched MeSH terms: Chickens/physiology*
  4. Nanostructured materials from hydroxyethyl cellulose for skin tissue engineering
    Zulkifli FH, Hussain FSJ, Rasad MSBA, Mohd Yusoff M
    Carbohydr Polym, 2014 Dec 19;114:238-245.
    PMID: 25263887 DOI: 10.1016/j.carbpol.2014.08.019
    In this study, a novel fibrous membrane of hydroxyethyl cellulose (HEC)/poly(vinyl alcohol) blend was successfully fabricated by electrospinning technique and characterized. The concentration of HEC (5%) with PVA (15%) was optimized, blended in different ratios (30-50%) and electrospun to get smooth nanofibers. Nanofibrous membranes were made water insoluble by chemically cross-linking by glutaraldehyde and used as scaffolds for the skin tissue engineering. The microstructure, morphology, mechanical and thermal properties of the blended HEC/PVA nanofibrous scaffolds were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, differential scanning colorimetry, universal testing machine and thermogravimetric analysis. Cytotoxicity studies on these nanofibrous scaffolds were carried out using human melanoma cells by the MTT assays. The cells were able to attach and spread in the nanofibrous scaffolds as shown by the SEM images. These preliminary results show that these nanofibrous scaffolds that supports cell adhesion and proliferation is promising for skin tissue engineering.
    Matched MeSH terms: Cell Proliferation/physiology
  5. Fulltext Food Consumption, Developmental Time, and Protein Profile of the Digestive System of the Red Palm Weevil, Rhynchophorus ferrugineus (Coleptera: Dryophthoridae) Larvae Reared on Three Different Diets
    Zulkifli AN, Zakeri HA, Azmi WA
    J Insect Sci, 2018 Sep 01;18(5).
    PMID: 30285257 DOI: 10.1093/jisesa/iey093
    The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (Coleoptera: Dryophthoridae) is one of the most dangerous pests of major cultivated palms including coconut, oil palm, and sago. The larval stage of the weevil causes the most destruction of the palms as it completely destroys the palm cabbage. In this study, the larvae were given three different diets-coconut cabbage, oil palm cabbage, and sago stem, under laboratory conditions for food consumption and developmental time experiment. The protein profiles of the digestive systems of the larvae fed on these three diets were also determined. Although the coconut diet was the most consumed by RPW larvae compared to oil palm and sago diets, the growth rate of RPW larvae on oil palm diet was however significantly shorter than those on the coconut and sago diets: the RPW only need 1 mo and 9 d to complete the larval duration. Proteins profiling of eight 2-DE gel protein spots that range 50-20 kDa were identified by mass spectrometry sequence analysis. Based on the Matrix Science Software, the most dominant protein was cationic trypsin. However, based on the NCBI BLAST tool, aminopeptidase N was the most dominant enzyme. This finding can lead to the development of pest control strategies based on the antinutritional protease inhibitors as potential biocontrol agents. Urgent action to find effective control methods should be taken seriously as this weevil is presumed to be one of the serious pests of oil palm industry in Malaysia.
    Matched MeSH terms: Larva/physiology; Weevils/physiology*
  6. Fulltext Probiotic Properties of Bacillus Strains Isolated from Stingless Bee (Heterotrigona itama) Honey Collected across Malaysia
    Zulkhairi Amin FA, Sabri S, Ismail M, Chan KW, Ismail N, Mohd Esa N, et al.
    Int J Environ Res Public Health, 2019 12 31;17(1).
    PMID: 31906055 DOI: 10.3390/ijerph17010278
    This study aimed to isolate, identify, and evaluate the probiotic properties of Bacillus species from honey of the stingless bee Heterotrigona itama. Bacillus spp. were isolated from five different H. itama meliponicultures, and the isolates were characterized through Gram-staining and a catalase test. Tolerance to acidic conditions and bile salt (0.3%), hydrophobicity, and autoaggregation tests were performed to assess the probiotic properties of the selected isolates, B. amyloliquefaciens HTI-19 and B. subtilis HTI-23. Both Bacillus isolates exhibited excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria and possessed significantly high survival rates in 0.3% bile solution for 3 h. Their survival rates in acidic conditions were also comparable to a commercial probiotic strain, Lactobacillus rhamnosus GG. Interestingly, the hydrophobicity and autoaggregation percentage showed no significant difference from L. rhamnosus GG, a commercial probiotic strain. The results from this study suggest that B. amyloliquefaciens HTI-19 and B. subtilis HTI-23 isolated from stingless bee honey have considerably good probiotic properties. Therefore, more studies should be done to investigate the effects of these bacteria cultures on gastrointestinal health.
    Matched MeSH terms: Bacillus/physiology*
  7. Fulltext Flavonoids as Potential Wound-Healing Molecules: Emphasis on Pathways Perspective
    Zulkefli N, Che Zahari CNM, Sayuti NH, Kamarudin AA, Saad N, Hamezah HS, et al.
    Int J Mol Sci, 2023 Feb 27;24(5).
    PMID: 36902038 DOI: 10.3390/ijms24054607
    Wounds are considered to be a serious problem that affects the healthcare sector in many countries, primarily due to diabetes and obesity. Wounds become worse because of unhealthy lifestyles and habits. Wound healing is a complicated physiological process that is essential for restoring the epithelial barrier after an injury. Numerous studies have reported that flavonoids possess wound-healing properties due to their well-acclaimed anti-inflammatory, angiogenesis, re-epithelialization, and antioxidant effects. They have been shown to be able to act on the wound-healing process via expression of biomarkers respective to the pathways that mainly include Wnt/β-catenin, Hippo, Transforming Growth Factor-beta (TGF-β), Hedgehog, c-Jun N-Terminal Kinase (JNK), NF-E2-related factor 2/antioxidant responsive element (Nrf2/ARE), Nuclear Factor Kappa B (NF-κB), MAPK/ERK, Ras/Raf/MEK/ERK, phosphatidylinositol 3-kinase (PI3K)/Akt, Nitric oxide (NO) pathways, etc. Hence, we have compiled existing evidence on the manipulation of flavonoids towards achieving skin wound healing, together with current limitations and future perspectives in support of these polyphenolic compounds as safe wound-healing agents, in this review.
    Matched MeSH terms: Wound Healing/physiology
  8. Fulltext Hearing loss in diving--a study amongst Navy divers
    Zulkaflay AR, Saim L, Said H, Mukari SZ, Esa R
    Med J Malaysia, 1996 Mar;51(1):103-8.
    PMID: 10967988
    Despite the commonly observed condition of middle and inner ear barotrauma among divers, there is little evidence of insidious and permanent development of sensorineural hearing loss associated with diving. An audiometric survey was performed on a group of 120 divers and 166 non divers from the Royal Malaysian Naval Base in Lumut, West Malaysia between July to December 1991. The results of this survey revealed that insidious development of high frequency sensorineural hearing loss may be associated with diving. At frequencies 4000, 6000 and 8000 Hz the divers had higher mean hearing levels than non divers and their hearing at those frequencies seemed to deteriorate faster. The etiology of this insidious hearing loss is multifactorial and may be related to inner ear barotrauma, decompression sickness or noise-induced deafness.
    Matched MeSH terms: Aging/physiology
  9. Evaluation of Shoulder and Knee Isokinetic Strength Profile Among Elite Adolescent Badminton Players
    Zulfikri N, Selvanayagam VS, Yusof A
    J Sport Rehabil, 2021 Jan 19;30(5):717-724.
    PMID: 33465761 DOI: 10.1123/jsr.2019-0483
    CONTEXT: Badminton continues to be a highly competitive sport where training is introduced at an early age and load has intensified. This exposes players to a greater risk of injuries, in particular when assessing related training outcomes such as strength, agonist-antagonist ratio, and bilateral deficit among adolescents where age- and sex-associated growth and development should be considered.

    OBJECTIVE: To evaluate strength profile of the upper and lower limbs among adolescent elite Malaysian badminton players.

    DESIGN: Cross-sectional study.

    SETTING: Laboratory.

    PARTICIPANTS: Forty-eight asymptomatic athletes (24 males and 24 females) were grouped into early and late adolescence (13-14 y old and 15-17 y old, respectively).

    MAIN OUTCOME MEASURE(S): Strength (absolute and normalized) of the external/internal rotators of the shoulder and flexor/extensor of the knee and strength derivatives, conventional strength ratio (CSR), dynamic control ratio (DCR), and bilateral deficits were measured.

    RESULTS: Males showed greater strength in all strength indices (P < .05). The older group had greater strength compared to younger for most of the upper and lower limb indices (P < .05); these effects diminished when using normalized data. For females, there was no age group effect in the shoulder and knee strength. All players displayed lower shoulder and knee normative values for CSR and DCR. Dominant and non-dominant knee strength were comparable between sex and age groups.

    CONCLUSIONS: For males, growth and maturation had a greater contribution to strength gained compared to training, whereas for females, growth, maturation, and training did not improve strength. The normalized data indicated that training did not improve all indices measured apart from external rotator strength in females. All players also displayed lower normative values of CSR and DCR. These results suggest that training in elite adolescent Malaysian badminton players lacks consideration of strength gain and injury risk factors.

    Matched MeSH terms: Knee Joint/physiology*; Functional Laterality/physiology; Shoulder Joint/physiology*; Racquet Sports/physiology*; Rotator Cuff/physiology; Muscle, Skeletal/physiology; Adolescent Development/physiology; Muscle Strength/physiology*; Physical Conditioning, Human/physiology
  10. Lethal and sublethal impacts of predaceous backswimmer Anisops wakefieldi (Hemiptera: Notonectidae) on the life-history traits of the New Zealand mosquito Culex pervigilans (Diptera: Culicidae)
    Zuharah WF, Fadzly N, Lester PJ
    J Med Entomol, 2013 Sep;50(5):1014-24.
    PMID: 24180106
    The presence of predators can have dramatic consequences on prey communities, not only by the direct effects of consumption but also through sublethal effects. We investigated the survival rate and subsequent life history of the mosquito Culex pervigilans Bergroth under the influence of its major predator, the backswimmer Anisops wakefieldi White. We established a field experiment with various treatments: 1) control without predators, 2) free-roaming A. wakefieldi (with one, three, or nine A. wakefieldi per container), 3) caged A. wakefieldi (empty cage without predators, with one, three, or nine A. wakefieldi in each cage, and 4) A. wakefieldi cues (with cues concentrations of one, three, or nine A. wakefieldi). Cx. pervigilans eggs were then taken from these four experimental treatments and reared in two different laboratory conditions: 1) in clean water without any traces of predators, or 2) in water with the same treatments as in field. The survival rate of Cx. pervigilans was significantly reduced by the presence of predators or their cues. Even after a brief exposure to waters containing predators or residual cues, the subsequent progeny and the ontogeny of the remaining survivors were still affected. The percentage of eggs that hatched, and the resulting mosquito population, was influenced by the presence of predators or their cues. Our results suggest that sublethal effects may be carried by surviving individuals primarily through the effects of stress, perhaps by epigenetic mechanisms. We may expect to observe similar plasticity in species or populations with high temporal or spatial variability in predation.
    Matched MeSH terms: Culex/physiology; Larva/physiology; Ovum/physiology; Pupa/physiology; Heteroptera/physiology*
  11. Fulltext The influence of aquatic predators on mosquito abundance in animal drinking troughs in New Zealand
    Zuharah WF, Lester PJ
    J Vector Ecol, 2010 Dec;35(2):347-53.
    PMID: 21175942 DOI: 10.1111/j.1948-7134.2010.00093.x
    The occurrence and abundance of mosquito populations may be associated with the abundance of predators. We examined the relationship between aquatic predators and populations of mosquitoes in animal water troughs in Waikanae, New Zealand. We also investigated the effects of water volume and environmental factors (temperature, rainfall, wind speed, humidity, and pressure) in order to further understand factors influencing mosquito and predator populations. Logistic regression indicated that the presence or absence of mosquitoes was primarily affected by three factors: predator abundance, week of observation, and water volume. Pearson's correlation indicated that the presence of predators had a positive correlation with water volume (r² = 0.176, p< 0.05). Otherwise, the presence of mosquito larvae in water troughs was negatively correlated with water volume (r² =-0.159, p=0.022) and wind speed (r² =0.142, p=0.041). We established a translocation experiment in which predators or mosquitoes were moved between troughs in order to examine the prey survival rate after exposure to Anisops wakefieldi predators. The survival rate of mosquitoes was not significantly different, between 0-0.1%, irrespective of the number of predators translocated (1-9) or the initial mosquito density (20-70 larvae). Our results suggested that A. wakefieldi predators may have the potential to be a promising biological control tool for the control of mosquito populations by altering mosquito population dynamics.
    Matched MeSH terms: Insects/physiology
  12. Developmental rate, size, and sexual dimorphism of Megaselia scalaris (Loew) (Diptera: Phoridae): its possible implications in forensic entomology
    Zuha RM, Omar B
    Parasitol Res, 2014 Jun;113(6):2285-94.
    PMID: 24728523 DOI: 10.1007/s00436-014-3883-z
    Cosmopolitan scuttle fly, Megaselia scalaris (Loew) (Diptera: Phoridae) is one of the commonest forensic species recorded colonizing human corpse indoors and in concealed environment. The occurrence of this species in such environments provides a higher evidential value to assist estimation of postmortem interval (PMI) compared to other forensically important dipterans. However, developmental and size data of M. scalaris are still lacking and they are derived from a limited range of thermal values. The objective of this study is to develop the growth model of M. scalaris by emphasizing the size range of larvae and puparia at different constant temperatures. This species was reared in six replicates at eight varying constant temperatures ranging from 23 to 36 °C and cow's liver was provided as food source. Larvae and puparia were sampled at set time intervals and measured by their length and weight. Because interpretation of forensic entomological evidence is subject to application of different techniques, development of M. scalaris is expressed herein by using developmental table, length/morphological stage diagrams and linear/nonlinear estimation methods. From the findings, it is very important to highlight that sexual dimorphism of M. scalaris during post feeding larva and pupa stage could be observed based on size and developmental periods. Mean length and weight ratios of male to female puparia are approximately 0.8 and 0.3-0.5, respectively, indicating sexual dimorphism of this species. Developmental period in female are 4.0-11.4 h (post feeding larval stage), 3.7-24.0 h (pupal stage), and 3.0-20.1 h (total developmental period) longer in male. Due to this dimorphism, PMI estimation using M. scalaris post feeding larva or puparium specimens must be carried out carefully by to avoid inaccuracy and misinterpretation.
    Matched MeSH terms: Diptera/physiology; Larva/physiology; Ovum/physiology; Pupa/physiology
  13. Fulltext Fly artifact documentation of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) - a forensically important blowfly species in Malaysia
    Zuha RM, Supriyani M, Omar B
    Trop Biomed, 2008 Apr;25(1):17-22.
    PMID: 18600200
    Analysis on fly artifacts produced by forensically important blowfly, Chrysomya megacephala (Fabricius) (Diptera:Calliphoridae), revealed several unique patterns. They can be divided into fecal spots, regurgitation spots and swiping stains. The characteristics of fecal spots are round with three distinct levels of pigmentation; creamy, brownish and darkly pigmented. Matrix of the spots appears cloudy. The round spots are symmetrical and non-symmetrical, delineated by irregular and darker perimeter which only visible in fairly colored fecal spots. Diameter of these artifacts ranged from 0.5 mm to 4 mm. Vomit or regurgitation spots are determined by the presence of craters due to sucking activity of blowflies and surrounded by thickly raised and darker colored perimeter. The size of these specks ranged from 1 mm to 2 mm. Matrix of the spots displays irregular surface and reflective under auxiliary microscope light. Swiping stains due to defecation by flies consists of two distinguishable segments, the body and tail. It can be seen as a tear drop-like, sperm-like, snake-like and irregular tadpole-like stain. The direction of body and tail is inconsistent and length ranged between 4.8 mm to 9.2 mm. A finding that should be highlighted in this observation is the presence of crater on tadpole-like swiping stain which is apparent by its raised border characteristic and reflective under auxiliary microscope light. The directionality of this darkly brown stain is random. This unique mix of regurgitation and swiping stain has never been reported before. Highlighting the features of artifacts produced by flies would hopefully add our understanding in differentiating them from blood spatters produced from victims at crime scenes.
    Matched MeSH terms: Diptera/physiology*
  14. Amycolatopsis thermophila sp. nov. and Amycolatopsis viridis sp. nov., thermophilic actinomycetes isolated from arid soil
    Zucchi TD, Tan GYA, Goodfellow M
    Int J Syst Evol Microbiol, 2012 Jan;62(Pt 1):168-172.
    PMID: 21378137 DOI: 10.1099/ijs.0.029256-0
    The taxonomic positions of two thermophilic actinomycetes isolated from an arid Australian soil sample were established based on an investigation using a polyphasic taxonomic approach. The organisms had chemical and morphological properties typical of members of the genus Amycolatopsis and formed distinct phyletic lines in the Amycolatopsis methanolica 16S rRNA subclade. The two organisms were distinguished from one another and from the type strains of related species of the genus Amycolatopsis using a range of phenotypic properties. Based on the combined genotypic and phenotypic data, it is proposed that the two isolates be classified in the genus Amycolatopsis as Amycolatopsis thermophila sp. nov. (type strain GY088(T)=NCIMB 14699(T)=NRRL B-24836(T)) and Amycolatopsis viridis sp. nov. (type strain GY115(T)=NCIMB 14700(T)=NRRL B-24837(T)).
    Matched MeSH terms: Actinomycetales/physiology
  15. Fulltext Hybrid mesh for nasal airflow studies
    Zubair M, Abdullah MZ, Ahmad KA
    Comput Math Methods Med, 2013;2013:727362.
    PMID: 23983811 DOI: 10.1155/2013/727362
    The accuracy of the numerical result is closely related to mesh density as well as its distribution. Mesh plays a very significant role in the outcome of numerical simulation. Many nasal airflow studies have employed unstructured mesh and more recently hybrid mesh scheme has been utilized considering the complexity of anatomical architecture. The objective of this study is to compare the results of hybrid mesh with unstructured mesh and study its effect on the flow parameters inside the nasal cavity. A three-dimensional nasal cavity model is reconstructed based on computed tomographic images of a healthy Malaysian adult nose. Navier-Stokes equation for steady airflow is solved numerically to examine inspiratory nasal flow. The pressure drop obtained using the unstructured computational grid is about 22.6 Pa for a flow rate of 20 L/min, whereas the hybrid mesh resulted in 17.8 Pa for the same flow rate. The maximum velocity obtained at the nasal valve using unstructured grid is 4.18 m/s and that with hybrid mesh is around 4.76 m/s. Hybrid mesh reported lower grid convergence index (GCI) than the unstructured mesh. Significant differences between unstructured mesh and hybrid mesh are determined highlighting the usefulness of hybrid mesh for nasal airflow studies.
    Matched MeSH terms: Nasal Cavity/physiology*; Respiratory Mechanics/physiology
  16. Fulltext A magnetic resonance imaging study on the articulatory and acoustic speech parameters of Malay vowels
    Zourmand A, Mirhassani SM, Ting HN, Bux SI, Ng KH, Bilgen M, et al.
    Biomed Eng Online, 2014;13:103.
    PMID: 25060583 DOI: 10.1186/1475-925X-13-103
    The phonetic properties of six Malay vowels are investigated using magnetic resonance imaging (MRI) to visualize the vocal tract in order to obtain dynamic articulatory parameters during speech production. To resolve image blurring due to the tongue movement during the scanning process, a method based on active contour extraction is used to track tongue contours. The proposed method efficiently tracks tongue contours despite the partial blurring of MRI images. Consequently, the articulatory parameters that are effectively measured as tongue movement is observed, and the specific shape of the tongue and its position for all six uttered Malay vowels are determined.Speech rehabilitation procedure demands some kind of visual perceivable prototype of speech articulation. To investigate the validity of the measured articulatory parameters based on acoustic theory of speech production, an acoustic analysis based on the uttered vowels by subjects has been performed. As the acoustic speech and articulatory parameters of uttered speech were examined, a correlation between formant frequencies and articulatory parameters was observed. The experiments reported a positive correlation between the constriction location of the tongue body and the first formant frequency, as well as a negative correlation between the constriction location of the tongue tip and the second formant frequency. The results demonstrate that the proposed method is an effective tool for the dynamic study of speech production.
    Matched MeSH terms: Speech/physiology*; Tongue/physiology
  17. Fulltext Allometry and Scaling of the Intraocular Pressure and Aqueous Humour Flow Rate in Vertebrate Eyes
    Zouache MA, Eames I, Samsudin A
    PLoS One, 2016;11(3):e0151490.
    PMID: 26990431 DOI: 10.1371/journal.pone.0151490
    In vertebrates, intraocular pressure (IOP) is required to maintain the eye into a shape allowing it to function as an optical instrument. It is sustained by the balance between the production of aqueous humour by the ciliary body and the resistance to its outflow from the eye. Dysregulation of the IOP is often pathological to vision. High IOP may lead to glaucoma, which is in man the second most prevalent cause of blindness. Here, we examine the importance of the IOP and rate of formation of aqueous humour in the development of vertebrate eyes by performing allometric and scaling analyses of the forces acting on the eye during head movement and the energy demands of the cornea, and testing the predictions of the models against a list of measurements in vertebrates collated through a systematic review. We show that the IOP has a weak dependence on body mass, and that in order to maintain the focal length of the eye, it needs to be an order of magnitude greater than the pressure drop across the eye resulting from gravity or head movement. This constitutes an evolutionary constraint that is common to all vertebrates. In animals with cornea-based optics, this constraint also represents a condition to maintain visual acuity. Estimated IOPs were found to increase with the evolution of terrestrial animals. The rate of formation of aqueous humour was found to be adjusted to the metabolic requirements of the cornea, scaling as Vac(0.67), where Vac is the volume of the anterior chamber. The present work highlights an interdependence between IOP and aqueous flow rate crucial to ocular function that must be considered to understand the evolution of the dioptric apparatus. It should also be taken into consideration in the prevention and treatment of glaucoma.
    Matched MeSH terms: Anterior Chamber/physiology; Aqueous Humor/physiology*; Cornea/physiology; Intraocular Pressure/physiology*
  18. Systematic review and meta-analysis of the prevalence of neuropathic-like pain and/or pain sensitization in people with knee and hip osteoarthritis
    Zolio L, Lim KY, McKenzie JE, Yan MK, Estee M, Hussain SM, et al.
    Osteoarthritis Cartilage, 2021 08;29(8):1096-1116.
    PMID: 33971205 DOI: 10.1016/j.joca.2021.03.021
    OBJECTIVE: To determine the prevalence of neuropathic-like pain (NP) and pain sensitization (PS) defined by self-report questionnaires in knee and hip osteoarthritis, and whether prevalence is potentially explained by disease-severity or affected joint.

    DESIGN: MEDLINE, EMBASE, CINAHL were systematically searched (1990-April 2020) for studies describing the prevalence of NP and PS in knee and hip osteoarthritis using self-report questionnaires. Random-effects meta-analysis was performed. Statistical heterogeneity between studies and sub-groups (affected joint and population source as a proxy for disease severity) was assessed (I2 statistic and the Chi-squared test).

    RESULTS: From 2,706 non-duplicated references, 39 studies were included (2011-2020). Thirty-six studies reported on knee pain and six on hip pain. For knee osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP(score ≥13) 40% (95%CI 32-48%); probable NP(score >18) 20% (95%CI 15-24%); using Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, 32% (95%CI 26-38%); using Douleur Neuropathique (DN4) 41% (95% CI 24-59%). The prevalence of PS using Central Sensitization Inventory (CSI) was 36% (95% CI 12-59%). For hip osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP 29% (95%CI 22-37%%); probable NP 9% (95%CI 6-13%); using DN4 22% (95%CI 12-31%) in one study. The prevalence of possible NP pain was higher at the knee (40%) than the hip (29%) (difference 11% (95% CI 0-22%), P = 0.05).

    CONCLUSIONS: Using self-report questionnaire tools, NP was more prevalent in knee than hip osteoarthritis. The prevalence of NP in knee and hip osteoarthritis were similar for each joint regardless of study population source or tool used. Whether defining NP using self-report questionnaires enables more effective targeted therapy in osteoarthritis requires investigation.

    Matched MeSH terms: Central Nervous System Sensitization/physiology*
  19. Fulltext Characterization and antimicrobial activities of two Streptomyces isolates from soil in the periphery of Universiti Putra Malaysia
    Zin NZ, Tasrip NA, Desa MN, Kqueen CY, Zakaria ZA, Hamat RA, et al.
    Trop Biomed, 2011 Dec;28(3):651-60.
    PMID: 22433896 MyJurnal
    This study was to assess the identification and antimicrobial activities of two actinomycete isolates. The two isolates designated as B8 and C2, were isolated from a patch of soil in the peripheral area of Universiti Putra Malaysia by streaking on starch casein agar after standard serial dilution procedures. Their antimicrobial activities were first evaluated against eight clinical laboratory strains namely Bacillus sp., Enterococcus sp., Escherichia coli, Klebsiella sp., Pseudomonas sp., Salmonella sp., Staphylococcus aureus, and Staphylococcus epidermidis by perpendicular streak method on Mueller Hinton and Tryptic Soy agar. In both media, a broad-spectrum antibacterial activity was observed for both isolates, with B8 against all the test bacteria and C2 against five of them (Bacillus sp., E. coli, Pseudomonas sp., S. aureus and S. epidermidis). Re-assessment against E. coli ATCC 25922 and S. aureus ATCC 25923 strains by similar method showed antibacterial activities by isolate B8 against both ATTC strains while C2 only against S. aureus ATCC 25923. Streptomyces griseus ATCC 10137 was included in the later experiment and showed antibacterial activity against both ATCC strains. Subsequently, the two isolates were identified by PCR/sequencing techniques and phylogenetic analysis to be Streptomyces species (>93% homology based on 16S rRNA and rpoB genes). Characterization on cultural characteristic and viable count at different temperatures (37ºC and 28ºC), on different microbiological media (AIA, ISP-2, MHA, NA, PDA and TSA), were performed. More morphological features were observed on ISP-2 for both isolates. A higher growth yield was also observed at 28ºC in all media but in comparing that between the two isolates, isolate B8 outnumbered C2 at all experimental conditions. The observed variation in cultural traits and growth yield indicate unique properties between the two antibiotic-producing isolates.
    Matched MeSH terms: Streptomyces/physiology*
  20. Bioactive endophytic streptomycetes from the Malay Peninsula
    Zin NM, Sarmin NI, Ghadin N, Basri DF, Sidik NM, Hess WM, et al.
    FEMS Microbiol Lett, 2007 Sep;274(1):83-8.
    PMID: 17608698
    Three novel endophytic streptomycetes have been isolated and characterized from plants with ethnobotanical uses on the Malay Peninsula including: Thottea grandiflora (family -Aristolochiaceae), Polyalthia spp. (family -Annonaceae), and Mapania sp. (family -Cyperaceae). Each isolate, as studied by scanning electron microscopy, has small hyphae, and produces typical barrel-shaped spores arising by hyphal fragmentation. Interestingly, although none has any detectable antibacterial killing properties, each has demonstrable killing activity against one or more pathogenic fungi including organisms such as Phytophthora erythroseptica, Pythium ultimum, Sclerotinia sclerotiorum, Mycosphaerella fijiensis and Rhizoctonia solani. Molecular biological studies on the rRNA gene sequence of each isolate revealed that it is distinct from all other genetic accessions of streptomyectes in GenBank, and each bears some genetic similarity to other streptomycetes. The bioactivity of each microbe was extractable in various organic solvents.
    Matched MeSH terms: Actinomycetales/physiology*
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