26 research outputs found

    Proliferation and Differentiation of Human Hair Follicle Stem Cells on Chitosan-Skin Engineered Template in Vitro

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    Hair follicles repeatedly regress and reconstitute themselves, suggesting the presence of intrinsic tissue stem cells. Among the unique characteristics of adult stem cells isolated from hair follicles is their ability to differentiate into keratinocytes. Study on chitosan skin-engineered templates (SETs) as scaffolds for the proliferation of human fibroblasts have shown the promise of SETs in facilitating skin cell growth in three-dimensional culture. High proliferation in three-dimensional culture using human cells allows the researcher to extensively evaluate the cultivation of desirable cell types on chitosan SETs. Therefore, this study aimed to evaluate the in vitro attachment, proliferation and differentiation of hair follicle stem cells (HFSCs) on a chitosan SETs. HFSCs were isolated from human scalp tissues using collagenase type I prior to propagation in supplemented CnT-07 media. The phenotype of the HFSCs was verified using the markers keratin-15 (K15) and CD200, as detected by immunocytochemical staining. The attachment and proliferation of the HFSCs on the chitosan SETs were evaluated using scanning electron microscopy (SEM), an alamar blue assay and a live/dead assay. Subsequently, the HFSCs were differentiated using CnT-2D differentiation media. The cells’ differentiation was verified using the markers involucrin and keratin-6 (K6), as detected by immunofluorescence staining. The HFSCs were successfully isolated, proliferated and differentiated according to staining positivity and microscopy imaging. HFSCs are able to proliferate and directly differentiate into keratinocytes on a chitosan SETs, which may facilitate their use in regenerative medicine

    Proliferation and Differentiation of Human Hair Follicle Stem Cells on Chitosan-Skin Engineered Template in Vitro

    Get PDF
    Hair follicles repeatedly regress and reconstitute themselves, suggesting the presence of intrinsic tissue stem cells. Among the unique characteristics of adult stem cells isolated from hair follicles is their ability to differentiate into keratinocytes. Study on chitosan skin-engineered templates (SETs) as scaffolds for the proliferation of human fibroblasts have shown the promise of SETs in facilitating skin cell growth in three-dimensional culture. High proliferation in three-dimensional culture using human cells allows the researcher to extensively evaluate the cultivation of desirable cell types on chitosan SETs. Therefore, this study aimed to evaluate the in vitro attachment, proliferation and differentiation of hair follicle stem cells (HFSCs) on a chitosan SETs. HFSCs were isolated from human scalp tissues using collagenase type I prior to propagation in supplemented CnT-07 media. The phenotype of the HFSCs was verified using the markers keratin-15 (K15) and CD200, as detected by immunocytochemical staining. The attachment and proliferation of the HFSCs on the chitosan SETs were evaluated using scanning electron microscopy (SEM), an alamar blue assay and a live/dead assay. Subsequently, the HFSCs were differentiated using CnT-2D differentiation media. The cells’ differentiation was verified using the markers involucrin and keratin-6 (K6), as detected by immunofluorescence staining. The HFSCs were successfully isolated, proliferated and differentiated according to staining positivity and microscopy imaging. HFSCs are able to proliferate and directly differentiate into keratinocytes on a chitosan SETs, which may facilitate their use in regenerative medicine

    Comparative in vitro activity of various antibiotic against planktonic and biofilm and the gene expression profile in Pseudomonas aeruginosa

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    P. aeruginosa is an opportunistic pathogen that is commonly found in nosocomial infections. The purpose of this study was to investigate the effects of seven antibiotics on P. aeruginosa planktonic growth, biofilm formation, and the expression of virulence factors. These antibiotics included Ciprofloxacin (CP), Amikacin (AMK), Vancomycin (VAN), Tetracycline (TET), Gentamicin (GEN), Erythromycin (Ery), and Clindamycin (CLI). Antibiotic susceptibility testing, Minimum Bactericidal Concentration (MBC), Minimum Inhibitory Concentration (MIC), growth curve, time-kill curve, biofilm inhibition and reduction assay, and RT-qPCR were used to assess the effects of these antibiotics on P. aeruginosa planktonic and biofilm. The clear zones of inhibition against P. aeruginosa for the CP, AMK, VAN, TET, GEN, Ery, and CLI were 26 mm, 20 mm, 21 mm, 22 mm, 20 mm, 25 mm and 23 mm, respectively. The MIC values for CP, AMK, VAN, TET, GEN, Ery and CLI against P. aeruginosa ranged from 0.25 to 1 µg/mL while the MBC values ranged from 1 and 0.5 to 2 µg/mL respectively. The growth, total viable counts (TVCs), bacterial adhesion and biofilm formation of P. aeruginosa were reduced after exposure to all the tested antibiotics in a dose-dependent manner. The RT-qPCR analysis showed that all the tested antibiotics share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest (lasR, lasI, fleN, fleQ and fleR, oprB and oprC) in P. aeruginosa. The results indicate that all of the tested antibiotics possess antimicrobial and anti-biofilm activities, and that they may be multiple inhibitors and moderators of P. aeruginosa virulence via a variety of molecular targets. This deduction requires to be investigated in vivo

    Factors Related to Smoking Habits of Male Adolescents

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    A cross-sectional study was conducted to identify the factors related to smoking habits of adolescents among secondary school boys in Kelantan state, Malaysia. A total of 451 upper secondary male students from day, boarding and vocational schools were investigated using a structured questionnaire. Cluster sampling was applied to achieve the required sample size. The significant findings included: 1) the highest prevalence of smoking was found among schoolboys from the vocational school; 2) mean duration of smoking was 2.5 years; 3) there were significant associations between smoking status and parents' smoking history, academic performance, perception of the health hazards of smoking, and type of school attended. Peer influence was the major reason students gave for taking up the habit. Religion was most often indicated by non-smokers as their reason for not smoking. Approximately 3/5 of the smokers had considered quitting and 45% of them had tried at least once to stop smoking. Mass media was indicated as the best information source for the students to acquire knowledge about negative aspects of the smoking habit. The authors believe an epidemic of tobacco use is imminent if drastic action is not taken, and recommend that anti-smoking campaigns with an emphasis on the religious aspect should start as early as in primary school. Intervention programs to encourage behavior modification of adolescents are also recommended

    Klasifikasi al-Quran terhadap tingkah laku manusia dalam membina peradaban

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    Sebagai panduan dan pedoman bagi manusia, al-Quran tidak hanya merangkumi perkara yang berkaitan dengan aqidah, ibadah, muamalah dan akhlak, tetapi juga membincangkan hal-hal yang berhubung kait dengan manusia, seperti asal kejadian, proses penciptaan serta matlamat dan tujuan mereka dicipta oleh Allah SWT. Al-Quran juga tidak ketinggalan membincangkan perilaku, sikap dan tabiat manusia, baik yang dapat dikesan oleh pancainderia mahupun yang tersembunyi dalam hati sanubari. Hal ini dimaktubkan dalam banyak surah dan ayat. Namun adanya penjelasan tentang hakikat tingkah laku ini kurang disedari oleh kebanyakan sarjana, sedangkan ianya amat penting untuk menyelesaikan masalah manusia yang berkaitan khususnya tingkah laku yang negatif. Mereka lebih banyak merujuk kepada sumber bukan daripada al-Quran ataupun pandangan sarjana barat semata-mata apabila membicarakan tentang tingkah laku dan perkara yang berhubungan dengannya. Sehubungan dengan itu, penulisan ini bertujuan membincangkan kepelbagaian tingkah laku manusia menerusi ayat al-Quran serta huraiannya. Huraian al-Quran mengenainya adalah isyarat kepada tranformasi tingkah laku manusia yang dianjurkan bagi membina peradaban yang unggul. Perbincangan merujuk kepada ayat al-Quran dan huraian serta analisisnya menurut sarjana Islam, khususnya dalam kalangan ahli tafsir. Boleh dirumuskan bahawa al-Quran telah mengisyaratkan kepelbagaian tingkah laku manusia samada tingkah laku yang meliputi aspek luaran manusia (fizikal) dan juga aspek dalaman (rohani). Mengetahui dan memahami kepelbagaian ini dapat membantu usaha menyelesaikan masalah yang dihadapi oleh seseorang dengan mengenal pasti diri mereka dari sudut tindakan dan perbuatannya

    A Multi - Centered Study Of The Influence Of Hiv Infection On The Transmission Of Tuberculosis To Household Contacts Three States Of Malaysia.

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    A multi-centered cross-sectional study was carried out to examine tuberculin (Mantoux) response among household contacts of pulmonary TB (PTB) patients registered in Kota Bharu Hospital, Kelantan; Alor Setar Hospital Kedah and Institute of Respiratory Medicine, Kuala Lumpur from year 2000 through 2004

    Power losses analysis of multiphase DC-DC buck converter using OrCAD PSpice software

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    DC-DC buck converters have wide applications in portable electronic devices, battery chargers, and telecommunications. However, single-phase DC-DC buck converters have some drawbacks, especially in high current applications, where the increase in the size of the inductor will increase power losses, which significantly affects the overall efficiency of the converter. The multiphase configuration offers several advantages, such as reduction in output voltage ripple, input current ripple, conduction loss, and the physical size of the hardware. This paper presents an analysis of the power losses of the multiphase DC-DC buck converter with output power ranging between 50 watts to 250 watts. To verify the effectiveness of the multiphase converter, performance analysis was done using OrCAD PSpice software, where the number of phases was limited to five phases. This paper focused on power losses in the converter, namely conduction losses in diodes and MOSFETs, switching loss in MOSFETs, as well as losses in the inductor and capacitor. The relationship between the number of phases and factors of switching frequency, output, and the components’ internal resistance was also highlighted and discussed in detail

    Spermidine Promotes Human Hair Growth and Is a Novel Modulator of Human Epithelial Stem Cell Functions

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Chitosan Dermal Substitute and Chitosan Skin Substitute Contribute to Accelerated Full-Thickness Wound Healing in Irradiated Rats

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    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
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