Perkembangan kesihatan buruh India di estet-estet di negeri Kedah, 1910-1945

Kajian ini bertujuan meninjau perkembangan kesihatan buruh India di estet di negeri Kedah antara tahun 1910-1945. Hasil kajian menunjukkan bahawa pennasalahan kesihatan buruh India di estet berpunca daripada sistem pengeluaran kapitalis yang berorientasikan keuntungan maksima. Untuk mencapai matlamat itu buruh India yang murah dari India Selatan telah dimanipulasi dengan bayaran upah yang rendah. Keadaan ini telah memiskinkan golongan buruh tersebut. Dalam hal ini, pengenalan Sistem Kangany serta amalan minum todi di kalangan buruh India di estet telah memburukkan lagi keadaan kemiskinan di estet. The research aims to study the development of health among Indian labourers in the Kedah estates, between the years 1910 and 1945. The results of the study revealed that health problems among estate workers of Indian origin started with the Capitalist System of Production, which was oriented towards maximising profits. With this objective in mind, cheap Indian labour from South India was manipulated with the payment of low wages. This act of manipulation resulted in the emergence of a group of poor labourers. Subsequently, the introduction of the 'Kangany' System and the habit of drinking toddy among these labourers in the estates further aggravated the conditions of poverty in estates

Production, Process Design and Quality Characterization of Catfish Visceral Oil.

Between 45--55% of viscera, head, skin, intestine and slurries are generally generated as byproducts or waste from catfish filleting process. Our preliminary study showed that the crude fat content of the whole catfish viscera was 30--35% (wet basis) and the total o-3 fatty acids of oils recovered from the whole and/or portioned viscera ranged from 4.3--20.9 mg/g (dry basis). Catfish viscera may serve as an excellent source of health-promoting oil. Yield of purified (deodorized) catfish visceral oil was 65.7% and contained considerable amounts of DHA (1.21 mg/g of oil) and omega-3 fatty acid (4.6 mg/g of oil). A rapid microwave-assisted method for fatty acid analysis was developed. The microwave heating power (%) and time (sec) required for maximal fatty acid recovery were determined. Heating at 100% power for 80 sec yielded the highest recovery of DHA (C22:6 o-3) and arachidonic acid (C20:4 o-3). The adsorption of free fatty acid of crude catfish oil was performed with chitosan, activated carbon and/or activated earth as adsorbents. Batch adsorbent experiments were carried out to assess equilibrium parameters. Chitosan was the most effective adsorbent to adsorb free fatty acids. The fixed-bed adsorption study showed that the highest percent of bed length was used when chitosan was used as an adsorbent. Melting points, specific heat capacity, enthalpy, and heat resistance were studied using DSC (Differential Scanning Calorimeter) and TGA (Thermogravimetric analysis). Melting points, enthalpy, and specific heat capacity varied greatly among the catfish oils from different processing stages due to differences in impurities. Catfish visceral oils from different processing steps showed different rates of weight loss with increased temperature. Suitability of Newtonian, Herschel-Bulkley, Bingham plastic, and Casson models to characterize the flow behavior of catfish oils form different processing steps was investigated. The Casson equation sufficiently described the flow behavior of catfish oils. The research findings from this study will benefit the whole catfish industries and will set a good model for fish oil recovery from other fish species as well

PTPα regulates integrin-stimulated FAK autophosphorylation and cytoskeletal rearrangement in cell spreading and migration

We investigated the molecular and cellular actions of receptor protein tyrosine phosphatase (PTP) α in integrin signaling using immortalized fibroblasts derived from wild-type and PTPα-deficient mouse embryos. Defects in PTPα−/− migration in a wound healing assay were associated with altered cell shape and focal adhesion kinase (FAK) phosphorylation. The reduced haptotaxis to fibronectin (FN) of PTPα−/− cells was increased by expression of active (but not inactive) PTPα. Integrin-mediated formation of src–FAK and fyn–FAK complexes was reduced or abolished in PTPα−/− cells on FN, concomitant with markedly reduced phosphorylation of FAK at Tyr397. Reintroduction of active (but not inactive) PTPα restored FAK Tyr-397 phosphorylation. FN-induced cytoskeletal rearrangement was retarded in PTPα−/− cells, with delayed filamentous actin stress fiber assembly and focal adhesion formation. This mimicked the effects of treating wild-type fibroblasts with the src family protein tyrosine kinase (Src-PTK) inhibitor PP2. These results, together with the reduced src/fyn tyrosine kinase activity in PTPα−/− fibroblasts (Ponniah et al., 1999; Su et al., 1999), suggest that PTPα functions in integrin signaling and cell migration as an Src-PTK activator. Our paper establishes that PTPα is required for early integrin-proximal events, acting upstream of FAK to affect the timely and efficient phosphorylation of FAK Tyr-397

Force-Bioreactor for Assessing Pharmacological Therapies for Mechanobiological Targets

Tissue fibrosis is a major health issue that impacts millions of people and is costly to treat. However, few effective anti-fibrotic treatments are available. Due to their central role in fibrotic tissue deposition, fibroblasts and myofibroblasts are the target of many therapeutic strategies centered primarily on either inducing apoptosis or blocking mechanical or biochemical stimulation that leads to excessive collagen production. Part of the development of these drugs for clinical use involves in vitro prescreening. 2D screens, however, are not ideal for discovering mechanobiologically significant compounds that impact functions like force generation and other cell activities related to tissue remodeling that are highly dependent on the conditions of the microenvironment. Thus, higher fidelity models are needed to better simulate in vivo conditions and relate drug activity to quantifiable functional outcomes. To provide guidance on effective drug dosing strategies for mechanoresponsive drugs, we describe a custom force-bioreactor that uses a fibroblast-seeded fibrin gels as a relatively simple mimic of the provisional matrix of a healing wound. As cells generate traction forces, the volume of the gel reduces, and a calibrated and embedded Nitinol wire deflects in proportion to the generated forces over the course of 6 days while overhead images of the gel are acquired hourly. This system is a useful in vitro tool for quantifying myofibroblast dose-dependent responses to candidate biomolecules, such as blebbistatin. Administration of 50 μM blebbistatin reliably reduced fibroblast force generation approximately 40% and lasted at least 40 h, which in turn resulted in qualitatively less collagen production as determined via fluorescent labeling of collagen

Discovery of SMAD4 promoters, transcription factor binding sites and deletions in juvenile polyposis patients

Inactivation of SMAD4 has been linked to several cancers and germline mutations cause juvenile polyposis (JP). We set out to identify the promoter(s) of SMAD4, evaluate their activity in cell lines and define possible transcription factor binding sites (TFBS). 5′-rapid amplification of cDNA ends (5′-RACE) and computational analyses were used to identify candidate promoters and corresponding TFBS and the activity of each was assessed by luciferase vectors in different cell lines. TFBS were disrupted by site-directed mutagenesis (SDM) to evaluate the effect on promoter activity. Four promoters were identified, two of which had significant activity in several cell lines, while two others had minimal activity. In silico analysis revealed multiple potentially important TFBS for each promoter. One promoter was deleted in the germline of two JP patients and SDM of several sites led to significant reduction in promoter activity. No mutations were found by sequencing this promoter in 65 JP probands. The predicted TFBS profiles for each of the four promoters shared few transcription factors in common, but were conserved across several species. The elucidation of these promoters and identification of TFBS has important implications for future studies in sporadic tumors from multiple sites, and in JP patients

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data