A note on the fractional Cauchy problems with nonlocal initial conditions

AbstractOf concern is the Cauchy problems for fractional integro-differential equations with nonlocal initial conditions. Using a new strategy in terms of the compactness of the semigroup generated by the operator in the linear part and approximating technique, a new existence theorem for mild solutions is established. An application to a fractional partial integro-differential equation with a nonlocal initial condition is also considered

Optimiranje podloge za enzimsku proizvodnju L-cisteina s pomoću Pseudomonas sp. Zjwp-14 primjenom metode odzivnih površina

Response surface methodology was applied to optimize medium constituents for enzymatic production of L-cysteine from DL-2-amino-Δ^2-thiazoline-4-carboxylic acid (DL-ATC) by a novel Pseudomonas sp. Zjwp-14. With the Plackett-Burman design experiment, glycerol, DL-ATC, yeast extract, and pH were found to be the most powerful factors among the eight tested variables that influence intracellular enzyme activity for biotransformation of DL-ATC to L-cysteine. In order to investigate the quantitative effects for four variables selected from Plackett-Burman design on enzyme activity, a central composite design was subsequently employed for further optimization. The determination coefficient (R^2) was 0.9817, and the results show that the regression models adequately explain the data variation and represent the actual relationships between the parameters and responses. The optimal medium for Pseudomonas sp. Zjwp-14 was composed of (in g/L): glycerol 16.94, DL-ATC 4.59, yeast extract 6.99, NaCl 5.0, peptone 5.0, beef extract 5.0, MgSO4·7H2O 0.4, and pH=7.94. Under the optimal conditions, the maximum intracellular enzyme activity of 918.7 U/mL in theory and 903.6 U/mL in the experiment were obtained, with an increase of 15.6 % compared to the original medium components. In a 5-litre fermentor, cultivation time for Pseudomonas sp. Zjwp-14 was cut down for 6 h and the maximum enzyme activity reached 929.6 U/mL.Primjenom metode odzivnih površina optimirani su sastojci podloge za enzimsku proizvodnju L-cisteina iz DL-amino-Δ^2-tiazolin-4-karboksilne kiseline (DL-ATC) s pomoću Pseudomonas sp. Zjwp-14. Upotrebom Plackett-Burmanova eksperimentalnog dizajna od 8 ispitanih varijabla, koje utječu na aktivnost enzima u stanici i biotransformaciju DL-ATC u L-cistein, odabrani su ovi najvažniji parametri: koncentracija glicerola, DL-ATC i kvaščeva ekstrakta, te pH-vrijednost. Za daljnje optimiranje četiriju odabranih varijabla uporabljen je centralno složeni plan. Koeficijent determinacije (R^2) iznosio je 0,9817, a rezultati pokazuju da je regresijski model prikladan za objašnjenje podataka i da predstavlja stvarni odnos parametara i odziva. Optimalni sastav podloge za uzgoj Pseudomonas sp. Zjwp-14 bio je (u g/L): glicerol 16,94; DL-ATC 4,59; kvaščev ekstrakt 6,99; NaCl 5,0; pepton 5,0; goveđi ekstrakt 5,0; MgSO4·7H2O 0,4 i pH=7,94. U optimalnim eksperimentalnim uvjetima postignuta je maksimalna aktivnost enzima u stanici od 903,6 U/mL (teorijska vrijednost bila je 918,7 U/mL), što čini povećanje od 15,6 % u usporedbi s početnim sastavom podloge. U reaktoru zapremnine 5 litara vrijeme uzgoja soja Pseudomonas sp. Zjwp-14 skraćeno je za 6 sati, a maksimalna aktivnost enzima dosegla je 929,6 U/mL

The effect of experimental warming on leaf functional traits, leaf structure and leaf biochemistry in Arabidopsis thaliana

<p>Abstract</p> <p>Background</p> <p>The leaf is an important plant organ, and how it will respond to future global warming is a question that remains unanswered. The effects of experimental warming on leaf photosynthesis and respiration acclimation has been well studied so far, but relatively little information exists on the structural and biochemical responses to warming. However, such information is very important to better understand the plant responses to global warming. Therefore, we grew <it>Arabidopsis thaliana </it>at the three day/night temperatures of 23/18°C (ambient temperature), 25.5/20.5°C (elevated by 2.5°C) and 28/23°C (elevated by 5°C) to simulate the middle and the upper projected warming expected within the 21st century for this purpose.</p> <p>Results</p> <p>The 28/23°C treatment significantly reduced the life span, total biomass and total weight of seeds compared with the other two temperatures. Among the three temperature regimes, the concentrations of starch, chlorophyll, and proline were the lowest at 28/23°C, whereas the total weight of seeds, concentrations of chlorophyll and proline, stomatal density (SD), stomatal conductance (g_s), net CO₂assimilation rate (A) and transpiration rate (E) were the highest at 25.5/20.5°C. Furthermore, the number of chloroplasts per cell and mitochondrial size were highest at 25.5/20.5°C and lowest at 28/23°C.</p> <p>Conclusions</p> <p>The conditions whereby the temperature was increased by 2.5°C were advantageous for <it>Arabidopsis</it>. However, a rise of 5°C produced negative effects, suggesting that lower levels of warming may benefit plants, especially those which belong to the same functional group as <it>Arabidopsis</it>, whereas higher levels of warming may produce negative affects. In addition, the increase in A under moderately warm conditions may be attributed to the increase in SD, chlorophyll content, and number of chloroplasts. Furthermore, starch accumulation in chloroplasts may be the main factor influencing chloroplast ultrastructure, and elevated temperature regulates plant respiration by probably affecting mitochondrial size. Finally, high SOD and CAT activities may enable plants grown at elevated temperatures to exhibit relatively high tolerance to temperature stress, thus alleviating the harmful effects of superoxide anion radicals and hydrogen peroxide.</p

Effects of Chinese Formula Jueyin Granules on Psoriasis in an Animal Model

Although Traditional Chinese medicine (TCM) is known to be effective for psoriasis patients, the responsible mechanisms still remain poorly understood. In this study, we aimed to evaluate the effect of one formula, named Jueyin granules (JYG) in the mouse model of the vaginal epithelium and tail epidermis. Additionally, we also determined the anti-inflammatory effects of JYG in an imiquimod- (IMQ-) induced psoriasis-like skin mouse model. Our results show that JYG can attenuate the IMQ-induced psoriasis-like inflammation, accompanied with increased epidermal hyperplasia. We also measured estrogenic stage mitosis of vaginal epithelial cells and the formation of granular cell layers in male mouse tails per 100 scales, as well as the tissue nitric oxide (NO) and malondialdehyde (MDA) levels using the ELISA method. The results suggest that JYG significantly inhibited mitosis in mouse vaginal epithelial cells, promoted the formation of the squamous epidermal granular layer in mice tails, and reduced the levels of NO and MDA in an imiquimod-induced psoriasis-like skin mouse model after 14 d (P<0.05). These results demonstrate that JYG might be an effective clinical treatment for psoriasis and the effects may be related to inhibited keratinocytes proliferation, improved parakeratotic epidermal cells, and reduced expression of NO and MDA

Effects of two Lactobacillus strains on lipid metabolism and intestinal microflora in rats fed a high-cholesterol diet

<p>Abstract</p> <p>Background</p> <p>The hypocholesterolemic effects of lactic acid bacteria (LAB) have now become an area of great interest and controversy for many scientists. In this study, we evaluated the effects of <it>Lactobacillus plantarum </it>9-41-A and <it>Lactobacillus fermentum </it>M1-16 on body weight, lipid metabolism and intestinal microflora of rats fed a high-cholesterol diet.</p> <p>Methods</p> <p>Forty rats were assigned to four groups and fed either a normal or a high-cholesterol diet. The LAB-treated groups received the high-cholesterol diet supplemented with <it>Lactobacillus plantarum </it>9-41-A or <it>Lactobacillus fermentum </it>M1-16. The rats were sacrificed after a 6-week feeding period. Body weights, visceral organ and fat pad weights, serum and liver cholesterol and lipid levels, and fecal cholesterol and bile acid concentrations were measured. Liver lipid deposition and adipocyte size were evaluated histologically.</p> <p>Results</p> <p>Compared with rats fed a high-cholesterol diet but without LAB supplementation, serum total cholesterol, low-density lipoprotein cholesterol and triglycerides levels were significantly decreased in LAB-treated rats (p < 0.05), with no significant change in high-density lipoprotein cholesterol levels. Hepatic cholesterol and triglyceride levels and liver lipid deposition were significantly decreased in the LAB-treated groups (p < 0.05). Accordingly, both fecal cholesterol and bile acids levels were significantly increased after LAB administration (p < 0.05). Intestinal <it>Lactobacillus </it>and <it>Bifidobacterium </it>colonies were increased while <it>Escherichia coli </it>colonies were decreased in the LAB-treated groups. Fecal water content was higher in the LAB-treated groups. Compared with rats fed a high-cholesterol diet, administration of <it>Lactobacillus plantarum </it>9-41-A resulted in decreases in the body weight gain, liver and fat pad weight, and adipocytes size (p < 0.05).</p> <p>Conclusions</p> <p>This study suggests that LAB supplementation has hypocholesterolemic effects in rats fed a high-cholesterol diet. The ability to lower serum cholesterol varies among LAB strains. Our strains might be able to improve the intestinal microbial balance and potentially improve intestinal transit time. Although the mechanism is largely unknown, <it>L. plantarum </it>9-41-A may play a role in fat metabolism.</p

Renal Protective Effect of Sirtuin 1

Silent information regulator 2 (Sir2) is a nicotinamide adenine dinucleotide-(NAD + -) dependent deacetylase. The homology of SIRT1 and Sir2 has been extensively studied. SIRT1 deacetylates target proteins using the coenzyme NAD + and is therefore linked to cellular energy metabolism and the redox state through multiple signalling and survival pathways. During the past decade, investigators have reported that SIRT1 activity is essential in cancer, neurodegenerative diseases, diabetes, cardiovascular disease, and other age-related diseases. In the kidneys, SIRT1 may inhibit renal cell apoptosis, inflammation, and fibrosis. Therefore its activation may also become a new therapeutic target in the patients with chronic kidney disease including diabetic nephropathy. In this paper, we would like to review the protective functions of sirtuins and the role of SIRT1 in the onset of kidney disease based on previous studies, including diabetic nephropathy, acute renal injury, chronic kidney disease as well as lupus nephritis

Delivery of Protein Kinase A by CRISPRMAX and Its Effects on Breast Cancer Stem-Like Properties

Protein kinase A (PKA) activation has recently been reported to inhibit epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) ability, which is considered to be responsible for chemoresistance and tumor recurrence in patients. While current studies mainly focus on gene manipulation of the EMT process, the direct delivery of PKA enzymes to cancer cells has never been investigated. Here, we utilize the commercial Lipofectamine CRISPRMAX reagent to directly deliver PKAs to breast cancer cells and evaluate its effects on EMT regulation. We optimized the delivery parameters with fluorescent-labeled bovine serum albumin, and successfully delivered fluorescent PKAs through CRISPRMAX into breast cancer cells. Then, we evaluated the biological effects by immunofluorescence, flow cytometry, mammosphere assay, and chemoresistance assay. Our data showed the expression of EMT-related markers, alpha-smooth muscle actin and N-cadherin, was downregulated after CRISPRMAX-PKA treatment. Although the CD44(+)/CD24(-) population did not change considerably, the size of mammospheres significantly decreased. In paclitaxel and doxorubicin chemoresistance assays, we noticed PKA delivery significantly inhibited paclitaxel resistance rather than doxorubicin resistance. Taken together, these results suggest our direct enzyme delivery can be a potential strategy for inhibiting EMT/CSC-associated traits, providing a safer approach and having more clinical translational efficacy than gene manipulation. This strategy will also facilitate the direct testing of other target enzymes/proteins on their biological functions

Rapid assessment of knowledge, attitudes, practices, and risk perception related to the prevention and control of Ebola virus disease in three communities of Sierra Leone

Questionnaire on Ebola knowledge, attitudes, practices, and risk perception in three communities of Sierra Leone, 2015. (DOCX 34 kb