1,014 research outputs found
Global transcript and phenotypic analysis of yeast cells expressing Ssa1, Ssa2, Ssa3 or Ssa4 as sole source of cytosolic Hsp70-Ssa chaperone activity.
BACKGROUND: Cytosolic Hsp70 is a ubiquitous molecular chaperone that is involved in responding to a variety of cellular stresses. A major function of Hsp70 is to prevent the aggregation of denatured proteins by binding to exposed hydrophobic regions and preventing the accumulation of amorphous aggregates. To gain further insight into the functional redundancy and specialisation of the highly homologous yeast Hsp70-Ssa family we expressed each of the individual Ssa proteins as the sole source of Hsp70 in the cell and assessed phenotypic differences in prion propagation and stress resistance. Additionally we also analysed the global gene expression patterns in yeast strains expressing individual Ssa proteins, using microarray and RT-qPCR analysis. RESULTS: We confirm and extend previous studies demonstrating that cells expressing different Hsp70-Ssa isoforms vary in their ability to propagate the yeast [PSI+] prion, with Ssa3 being the most proficient. Of the four Ssa family members the heat inducible isoforms are more proficient in acquiring thermotolerance and we show a greater requirement than was previously thought, for cellular processes in addition to the traditional Hsp104 protein disaggregase machinery, in acquiring such thermotolerance. Cells expressing different Hsp70-Ssa isoforms also display differences in phenotypic response to exposure to cell wall damaging and oxidative stress agents, again with the heat inducible isoforms providing better protection than constitutive isoforms. We assessed global transcriptome profiles for cells expressing individual Hsp70-Ssa isoforms as the sole source of cytosolic Hsp70, and identified a significant difference in cellular gene expression between these strains. Differences in gene expression profiles provide a rationale for some phenotypic differences we observed in this study. We also demonstrate a high degree of correlation between microarray data and RT-qPCR analysis for a selection of genes. CONCLUSIONS: The Hsp70-Ssa family provide both redundant and variant-specific functions within the yeast cell. Yeast cells expressing individual members of the Hsp70-Ssa family as the sole source of Ssa protein display differences in global gene expression profiles. These changes in global gene expression may contribute significantly to the phenotypic differences observed between the Hsp70-Ssa family members
MITIGASI SEDIMENTASI SALURAN PERTAMBAKAN IKAN DAN UDANG DENGAN SEDIMEN EMULSIFIER DI WILAYAH KEC. MARGOYOSO – PATI
Permasalahan sedimentasi, tatakelola dan managemen saluran menjadi masalah
pertambakan kawasan pantai utara Jawa Tengah. Permasalahan ini mengakibatkan
berkurangnya volume pasokan air dan menurunkan kualitas air hingga timbulnya early
mortality syndrome (EMS) pada organisme yang dibudidayakan. Meningkatnya Sea Level
Rise (SLR) tidak menambah jumlah pasokan air dikarenakan kekuatan sedimentasi dua
arah dikawasan muara (pantai) membentuk delta. Kondisi ini dibutuhkan mitigasi
pengelolaan saluran untuk memberikan ruang transport material maupun pengarahan
sedimen dari lautan. Dua lokasi saluran pertambakan dan muara kawasan pertambakan
Margoyoso dijadikan sample untuk aplikasi “sedimen emulsifier” dan “bamboo
revetment”. Metode deskriptive digunakan dalam studi ini, aplikasi alat emulsifier dan
managemen air secara komprehensif ini menggunakan pendekatan Participatory Rural
Appraisal (PRA). Hasil menunjukkan bahwa tingkat keterisian tambak selama 2 bulan uji
coba mencapai 80% di dukuh Tapen, dan 72 % di dukuh Kemiri Desa Kertomulyo.
Sementara pada 2 bulan sebelum aplikasi alat hanya 35% dan 37% di kedua dukuh
tersebut. Laju sedimentasi menurun mencapai 70% per minggu di kedua lokasi dengan 2
kali treatment per minggu pada hari hari hujan. Sementara pada hari hari panas sedimentasi
berkurang hampir 90 % dengan hanya satu kali treatment
PENGARUH KEPEMIMPINAN DAN KNOWLEDGE MANAGEMENT TERHADAP KINERJA USAHA MIKRO, KECIL DAN MENENGAH KABUPATEN KARAWANG
This research was conducted on MSMEs in Karawang Regency in the food business sector. The type of research is quantitative with associative techniques. The sample used was 100 MSMEs with sample determination using the Simple Random Sampling technique. The data analysis technique used is multiple linear regression analysis technique. The research results show that leadership and knowledge management partially influence the performance of MSMEs while simultaneously showing that the contribution of both variables is 14.1% and has an effect on increasing the performance of MSMEs in the food sector in Karawang Regency. This means that improving the performance of MSMEs is influenced by these two variables, even though the contribution is low, they play a role in improving the performance of MSMEs.
 
Smolyak's algorithm: A powerful black box for the acceleration of scientific computations
We provide a general discussion of Smolyak's algorithm for the acceleration
of scientific computations. The algorithm first appeared in Smolyak's work on
multidimensional integration and interpolation. Since then, it has been
generalized in multiple directions and has been associated with the keywords:
sparse grids, hyperbolic cross approximation, combination technique, and
multilevel methods. Variants of Smolyak's algorithm have been employed in the
computation of high-dimensional integrals in finance, chemistry, and physics,
in the numerical solution of partial and stochastic differential equations, and
in uncertainty quantification. Motivated by this broad and ever-increasing
range of applications, we describe a general framework that summarizes
fundamental results and assumptions in a concise application-independent
manner
A mesocosm experiment investigating the effects of substratum quality and wave exposure on the survival of fish eggs
In a mesocosm experiment, the attachment of bream (Abramis brama) eggs to spawning substrata with and without periphytic biofilm coverage and their subsequent survival with and without low-intensity wave exposure were investigated. Egg attachment was reduced by 73% on spawning substrata with a natural periphytic biofilm, compared to clean substrata. Overall, this initial difference in egg numbers persisted until hatching. The difference in egg numbers was even increased in the wave treatment, while it was reduced in the no-wave control treatment. Exposure to a low-intensity wave regime affected egg development between the two biofilm treatments differently. Waves enhanced egg survival on substrata without a biofilm but reduced the survival of eggs on substrata with biofilm coverage. In the treatment combining biofilm-covered substrata and waves, no attached eggs survived until hatching. In all treatments, more than 75% of the eggs became detached from the spawning substrata during the egg incubation period, an
Production of 3,4-dihydroxy L-phenylalanine by a newly isolated Aspergillus niger and parameter significance analysis by Plackett-Burman design
<p>Abstract</p> <p>Background</p> <p>The amino acid derivative 3,4-dihydroxy L-phenylalanine (L-dopa) is gaining interest as a drug of choice for Parkinson's disease. <it>Aspergillus oryzae </it>is commonly used for L-dopa production; however, a slower growth rate and relatively lower tyrosinase activity of mycelia have led to an increasing interest in exploiting alternative fungal cultures. In the present investigation, we report on the microbiological transformation of L-tyrosine to L-dopa accomplished by a newly isolated filamentous fungus <it>Aspergillus niger</it>.</p> <p>Results</p> <p>The culture <it>A. niger </it>(isolate GCBT-8) was propagated in 500 ml Erlenmeyer flasks and the pre-grown mycelia (48 h old) were used in the reaction mixture as a source of enzyme tyrosinase. Grinded mycelia gave 1.26 fold higher L-dopa production compared to the intact at 6% glucose (pH 5.5). The rate of L-tyrosine consumption was improved from 0.198 to 0.281 mg/ml. Among the various nitrogen sources, 1.5% peptone, 1% yeast extract and 0.2% ammonium chloride were optimized. The maximal L-dopa was produced (0.365 mg/ml) at 0.3% potassium dihydrogen phosphate with L-tyrosine consumption of 0.403 mg/ml.</p> <p>Conclusion</p> <p>Over ~73% yield was achieved (degree of freedom 3) when the process parameters were identified using 2k-Plackett-Burman experimental design. The results are highly significant (p ≤ 0.05) and mark the commercial utility (LSD 0.016) of the mould culture which is perhaps the first ever report on L-dopa production from <it>A. niger</it>.</p
The Disrupt CAD II Study
BACKGROUND: The feasibility of intravascular lithotripsy (IVL) for modification of severe coronary artery calcification (CAC) was demonstrated in the Disrupt CAD I study (Disrupt Coronary Artery Disease). We next sought to confirm the safety and effectiveness of IVL for these lesions. METHODS: The Disrupt CAD II study was a prospective multicenter, single-arm post-approval study conducted at 15 hospitals in 9 countries. Patients with severe CAC with a clinical indication for revascularization underwent vessel preparation for stent implantation with IVL. The primary end point was in-hospital major adverse cardiac events (cardiac death, myocardial infarction, or target vessel revascularization). An optical coherence tomography substudy was performed to evaluate the mechanism of action of IVL, quantifying CAC characteristics and calcium plaque fracture. Independent core laboratories adjudicated angiography and optical coherence tomography, and an independent clinical events committee adjudicated major adverse cardiac events. RESULTS: Between May 2018 and March 2019, 120 patients were enrolled. Severe CAC was present in 94.2% of lesions. Successful delivery and use of the IVL catheter was achieved in all patients. The post-IVL angiographic acute luminal gain was 0.83±0.47 mm, and residual stenosis was 32.7±10.4%, which further decreased to 7.8±7.1% after drug-eluting stent implantation. The primary end point occurred in 5.8% of patients, consisting of 7 non-Q-wave myocardial infarctions. There was no procedural abrupt closure, slow or no reflow, or perforations. In 47 patients with post-percutaneous coronary intervention optical coherence tomography, calcium fracture was identified in 78.7% of lesions with 3.4±2.6 fractures per lesion, measuring 5.5±5.0 mm in length. CONCLUSIONS: In patients with severe CAC who require coronary revascularization, IVL was safely performed with high procedural success and minimal complications and resulted in substantial calcific plaque fracture in most lesions. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03328949
Comparative Tuberculosis (TB) Prevention Effectiveness in Children of Bacillus Calmette-Guérin (BCG) Vaccines from Different Sources, Kazakhstan
Except during a 1-year period when BCG vaccine was not routinely administered, annual coverage of infants with Bacillus Calmette-Guérin (BCG) in Kazakhstan since 2002 has exceeded 95%. BCG preparations from different sources (Japan, Serbia, and Russia) or none were used exclusively in comparable 7-month time-frames, September through March, in 4 successive years beginning in 2002. Our objective was to assess relative effectiveness of BCG immunization.Although there were differences in prevention effectiveness observed among the three BCG vaccines, all were protective. The Japanese vaccine (currently used in Kazakhstan), the Serbian vaccine, and the Russian vaccine respectively were 69%, 43%, and 22% effective with respect to clinical TB notifications, and 92%, 82%, and 51% effective with respect to culture confirmed TB. All three vaccines were >70% effective with respect to TB meningitis.Potential limitations included considerations that 1) the methodology used was retrospective, 2) multiple risk factors could have varied between cohorts and affected prevention effectiveness measures, 3) most cases were clinically diagnosed, and TB culture-positive case numbers and TB meningitis case numbers were sparse, and 4) small variations in reported population TB burden could have affected relative risk of exposure for cohorts.All three BCG vaccines evaluated were protective against TB, and prevention effectiveness varied by manufacturer. When setting national immunization policy, consideration should be given to prevention effectiveness of BCG preparations
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