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1.
Abnormal activation of Toll-like receptor (TLRs) signaling can result in colon cancer development. The aim of this study was to investigate the expression of important TLRs in different histological types of colorectal polyps and evaluate their relationship with intestinal microbiota. The expression levels of TLR2, 3, 4, and 5 were analyzed in intestinal biopsy specimens of 21 hyperplastic polyp (HP), 16 sessile serrated adenoma (SSA), 29 tubular adenoma (TA), 21 villous/tubulovillous (VP/TVP) cases, and 31 normal controls. In addition, selected gut bacteria including Streptococcus bovis, Enterococcus faecalis, Enterotoxigenic Bacteroides fragilis (ETBF), Fusobacterium nucleatum, Porphyromonas spp., Lactobacillus spp., Roseburia spp., and Bifidobacterium spp. were quantified in fecal samples using absolute qRT PCR, and, finally, the association between TLRs and these gut microbiota- was evaluated by Spearman’s correlation coefficient. Higher expression of TLR2 and TLR4 in VP/TVP and TA, and lower expression levels of TLR3 and TLR5 in all type of polyps were observed. The differences in TLR expression patterns was not only dependent on the histology, location, size, and dysplasia grade of polyps but also related to the intestinal microbiota patterns. TLR2 and TLR4 expression was directly associated with the F. nucleatum, E. faecalis, S. bovis, Porphyromonas, and inversely to Bifidobacterium, Lactobacillus, and Roseburia quantity. Furthermore, TLR3 and TLR5 expression was directly associated with Bifidobacterium, Roseburia, and Lactobacillus quantity. Our results suggest a possible critical role of TLRs during colorectal polyp progression. An abnormal regulation of TLRs in relation to gut microbial quantity may contribute to carcinogenesis.  相似文献   
2.
The wavelength-based machine, or simply w-machine, is an optical computational model, which is designed based on simultaneous movement of several wavelengths in a single light ray, and simultaneous effect of simple optical devices on them. In this paper, we investigate nonuniform complexity classes of w-machine, based on three complexity measures, namely, size, time, and word length. We show that the class of languages which can be generated by constant size nonuniform w-machines contain infinitely many Turing undecidable languages. Also, we show that polynomial size nonuniform w-machines generate all NP languages, and every NP-hard language requires at least polynomial time and polynomial size nonuniform w-machines to be generated. We prove that the class of languages which can be generated by polynomial size nonuniform w-machines is equal to NP/poly, and almost all languages require exponential size and polynomial time nonuniform w-machines to be generated.  相似文献   
3.
In this paper, an optical wavelength-based method to solve a well-known NP-complete problem 3-SAT is provided. In the 3-SAT problem, a formula F in the form of conjunction of some clauses over Boolean variables is given and the question is to find if F is satisfiable or not. The provided method uses exponential number of different wavelengths in a light ray and considers each group of wavelengths as a possible value-assignment for the variables. It then uses optical devices to drop wavelengths not satisfying F from the light ray. At the end, remaining wavelengths indicate satisfiability of the formula. The method provides two ways to arrange the optical devices to select satisfying wavelengths for a given clause: simple clause selectors and combined clause selectors, both requiring exponential preprocessing time. After preprocessing phase, the provided method requires polynomial time and optical devices to solve each problem instance.  相似文献   
4.
OBJECTIVES: This study sought to characterize occupational dermatoses and cutaneous hazards. METHODS: Workers' compensation claims filed for skin disease in the Washington State Fund were analyzed for 1989 through 1993; incidence rates for industries and employers were calculated, and cutaneous hazards associated with the highest rates were identified. RESULTS: A total of 7445 claims were filed for skin disorders, principally contact dermatitis; 675 (9.1%) involved more than 3 missed work-days. The rate of accepted skin disorder claims was 1.0 per 1000 full-time employee-years. The highest incidence rates (4.6 to 30.7 accepted claims per 1000 full-time employee-years) were in certain manufacturing industries (plastics related, concrete products, aircraft parts, sporting goods, and boat building), wholesale farm product raw materials, automotive glass replacement, and beauty shops. Seven of the 10 employers with the highest incidence rates (19.6 to 85.5 accepted claims per 1000 full-time employee-years) used fiber-reinforced plastics (composites) and exposed workers to epoxy and other resin systems associated with contact dermatitis. CONCLUSIONS: Workers' compensation data identify known and emerging workplace cutaneous hazards and show promise for targeting prevention efforts.  相似文献   
5.
Six aromatic oligoazomethines were synthesized containing seven benzene rings each. The terminal rings were substituted with different groups, namely, H, Cl, NO2, OH, OCH3 and CH3. The synthesis was carried out by condensing the para‐substituted benzaldehydes with benzidine to give the three‐ring compound, which was then condensed with terephthaldehyde to give the respective seven‐benzene‐ring oligomers. The oligomers were characterized by elemental analysis, electronic spectra, Fourier‐transform infrared and thermal analysis. The oligomers were used to investigate the effects of their molecular structure on their electronic spectra, as well as their thermal, electronic and electrical properties. The different conformers were reported and compared. The DC electrical conductivity variation of oligoazomethines was studied in the temperature range 300–500 K after annealing for 24 h at 100 °C and after doping with 5% I2. An attempt was made to relate the DC electrical conductivity, electronic properties and thermal properties to the chain length, substituted groups and coplanarity. The fairly low conductivity obtained was attributed to the non‐linearity of the rings in the chain. The different groups (neutral, electron withdrawing or electron donating) attached at the ends of the oligomer showed no influence upon the conductivity of the different oligomers. The action of doping gave almost the same enhancement as that noticed in the case of a long‐chain polymer. The DC electrical conductivity was interpreted using the band energy model. The seven‐benzene‐ring oligomer gave the same DC electrical conductivity as the long‐chain polymer. Copyright © 2004 Society of Chemical Industry  相似文献   
6.
We examined six radioimmunoassay procedures for measuring primary bile acids in human serum (two 3H-labeled and four 125I-labeled). A significant (p < 0.01) correlation was observed between measurements in the assay both for cholic acid and chenodeoxycholic acid, at low and high concentrations of serum bile acids. All kits were acceptable with respect to accuracy, precision, stability, and analytical recovery. All six procedures gave similar results for chenodeoxycholic and cholic acid in sera of 80 healthy subjects; the agreement was also close when the two primary bile acids were compared with their sum in serum. Normal values ranged from 0.4 to 2.5 mumol/L for conjugated chenodeoxycholic acid and from 0.3 to 1.5 mumol/L for conjugated cholic acid. The 125I assays do not require liquid-scintillation equipment but 125I induces a decrease in the affinity constant of antibody. The sensitivity of the assays was still adequate for measuring bile acids in the serum of healthy fasting persons and liver-disease patients.  相似文献   
7.
Bioactive wound dressings from poly(vinyl alcohol) (PVA) and zein nanoparticles (NPs) loaded with diclofenac (DLF) were prepared successfully by the single jet electrospinning method. DLF‐loaded zein NPs with an average diameter of ~228 nm were prepared using anti‐solvent precipitation method. The formulation of zein:DLF 1:1 exhibited optimum encapsulation efficiency of 47.80%. The NPs were characterized by dynamic light scattering, zeta‐potential measurement, and differential scanning calorimetry. In vitro, drug release profiles of the DLF‐loaded zein NPs, and PVA–zein NPs were also studied within 120 h and showed the release efficiency of nearly 80% from zein NPs. A more controlled release of DLF was achieved by embedding the zein NPs in the PVA nanofibers. Fourier transform infrared spectroscopy was used to analyze possible interactions between different components of the fabricated dressings. The mechanical properties of the developed dressings were also evaluated using uniaxial tensile testing. Young's modulus (E) of the dressings decreased after inclusion of zein NPs within the PVA nanofibers. Moreover, fibroblast culturing experiments proved that the composite dressings supported better cell attachment and proliferation compared to PVA nanofibers, by exhibiting moderate hydrophilicity. The results suggested that the electrospun composite dressing of PVA nanofibers and zein NPs is a promising topical drug‐delivery system and have a great potential for wound healing application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46643.  相似文献   
8.
The presence of a positive hepatitis B surface antigen (HBsAg) has been considered a highly questionable indication for orthotopic liver transplantation. We report our experience in the treatment of HBsAg-positive HBV-DNA-negative cirrhotics with liver transplantation, whether or not followed by passive prophylaxis with specific immunoglobulins. Of the 123 cirrhotics who received transplants at our institution since May 1986, 39 (31.7%) were HBsAg positive; of these, 1 was HBV-DNA positive, and 4 were hepatitis Be antigen (HBeAg) positive. Since April 1991, 25 HBsAg-positive HBV-DNA-negative cirrhotics have undergone an original protocol with the periodical intramuscular administration of 5,000 IU of specific immunoglobulins starting in the anhepatic phase and lasting for at least 1 year. There were no differences among cirrhotics in terms of operative mortality and long-term survival with respect to the presence of the HBsAg. Of the 35 HBsAg-positive HBV-DNA-negative patients having a follow-up of 1 month or longer, 12 (34.3%) developed HBsAg recurrence; of them, 4 (33.3%) had received a complete prophylaxis, whereas 8 (66.7%) had not. The recurrence rate was 80% (8 out of 10) in the group of patients who had not received the prophylaxis and 16% (4 out of 25) in the group who had received the prophylaxis (P = .0003). The actuarial recurrence rate in the treated patients was 20.2% and 20.2% after 1 and 3 years, respectively, whereas in the untreated group it was 60.0% and 70.0% (P < .01). The hazard of recurrence of treated patients was reduced to 24.9% compared with untreated patients. Liver transplantation can be performed in HBsAg-positive HBV DNA negative patients without an increase in the operative risk or a worsening of long-term results. Immunoglobulin prophylaxis seems to be effective in preventing hepatitis recurrence after transplantation.  相似文献   
9.
Two sequencing batch reactors were operated to investigate the effect of influent alkalinity and reactor pH on aerobic granulation. In the first reactor R1 with high influent alkalinity the pH was adjusted in the neutral range, and in the second reactor R2 with low alkalinity the pH was held within the acidic range. The R1‐dominating species were bacteria and the appearance time of granules was three weeks after reactor start‐up. On the other hand, the acidic environment of R2 provided favorable conditions for fungal growth, and rapid granule formation occurred within the first week of operation. The varying microbial structure of granules resulted in different reactor performance in terms of evolution time and morphology of granules, suspended solids in the reactors, settling ability of granules, effluent quality of treated wastewater, and physical strength of the granules.  相似文献   
10.
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