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81.
Numerous molecular mechanisms are being examined in an attempt to discover disease-modifying drugs to slow down the underlying neurodegeneration in Alzheimer’s disease.Recent studies have shown the beneficial effects of epidermal growth factor receptor inhibitors on the enhancement of behavioral and pathological sequelae in Alzheimer’s disease.Despite the promising effects of epidermal growth factor receptor inhibitors in Alzheimer’s disease,there is no irrefutable neuroprotective evidence in well-established animal models using epidermal growth factor receptor inhibitors due to many un-explored downstream signaling pathways.This caused controversy about the potential involvement of epidermal growth factor receptor inhibitors in any prospective clinical trial.In this review,the mystery beyond the under-investigation of epidermal growth factor receptor in Alzheimer’s disease will be discussed.Furthermore,their molecular mechanisms in neurodegeneration will be explained.Also,we will shed light on SARS-COVID-19 induced neurological manifestations mediated by epidermal growth factor modulation.Finally,we will discuss future perspectives and under-examined epidermal growth factor receptor downstream signaling pathways that warrant more exploration.We conclude that epidermal growth factor receptor inhibitors are novel effective therapeutic approaches that require further research in attempts to be repositioned in the delay of Alzheimer’s disease progression.  相似文献   
82.
Development of late-onset Becker muscular dystrophy is reported in a patient whose two healthy brothers showed high serum creatine kinase level. No cases of neuromuscular disorders had been previously reported in this family. The analysis of the dystrophin gene showed that the three brothers had A → C transversion at nucleotide 6092 in exon 41, a missense mutation which converts lysine into glutamine. The symptomatic patient showed an additional mutation in the same exon, a T → C transition at nucleotide 6119, converting a phenylalanine to leucine. The possible pathogenic role of this mutation is discussed. Am. J. Med. Genet. 80:99–102, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
83.
BackgroundT2DM patients are more likely to have UTIs caused by resistant organisms such as ESBLs producing bacteria. Challenging reliable identification and prompt characterization of in-vitro susceptibilities of these bacteria are the first steps of deciding the appropriate antimicrobial therapy for UTIs caused by them.ObjectivesTo isolate and identify E. coli and K. pneumoniae from urine of T2DM patients with UTIs, to determine antibiotic resistance pattern among isolates, and to identify ESBLs production phenotypically and genotypically.Material and methodAll samples were cultured on Cystine-Lactose-Electrolyte-Deficient Agar medium (CLED) by using calibrated loop. Growth of 100 colonies or more, i.e. 105 colony forming units (CFU)/mL urine was considered as significant bacteriuria. Isolation and identification were done according to standard method. All isolates were tested for antibiotic susceptibility testing by the disc diffusion method according to CLSI guidelines. Phenotypic detection of ESBLs was done by double-disk synergy test. Genotypic detection of blaTEM, blaSHV and blaCTX-M genes by using PCR.ResultsResults of this study showed that E. coli and K. pneumoniae were the dominant bacterial isolates, they constituted 103 (91.2%) out of 113 urine isolates. E. coli (58. 4%) K. pneumoniae (32.7%), Enterococcus spp. (4.4%), Proteus spp. (2.7%) and Pseudomonas spp. (1.8%). About 25 (24.3%) out of 103 E. coli and K. pneumoniae isolates were ESBLs positive by DDST, and 22 (88.0%) out of them had ESBLs encoding genes by conventional PCR. The most common gene detected was blaTEM (59.1%), followed by blaSHV (27.3%). CTX-M had not been detected in any of testes isolates.ConclusionblaTEM and blaSHV genes were detected in 22 out of 25 ESBLs producing E. coli and K. pneumoniae isolates phenotypically detected by DDST. blaTEM was found to be the predominant gene (59.1%), while blaCTX-Mene was not detected in any of tested isolates.  相似文献   
84.
85.

Background

Neoadjuvant chemotherapy (NAC) has clinically important outcome. Early evaluation of the treatment response is important to avoid unnecessary therapy in non-responders. MRI is the most sensitive imaging for monitoring NAC response.

Aim of this study

Is to test the ability of DWI to detect early response to NAC.

Results

The study was performed on 20 patients, proved pathologically to have invasive breast cancer. All patients underwent breast MRI before initiation of NAC, after one cycle and after completion of the NAC protocol. Regarding the mass size, results showed no significant change in maximum mass diameters occur after the 1st NAC cycle. Absolute value of the ADC show increase all along the treatment course which has no significant correlation with the pathological response. The relative increase ADC more than 20% calculated from subtraction of the pre-treatment ADCmean value from that after the first NAC, subdividing the result on the pre-treatment ADCmean value and multiply it by 100 reflected significantly on the pathological response (p value of 0.011).

Conclusion

ADC value can predict responder from non-responder as early as after the first cycle of chemotherapy.  相似文献   
86.
Background: Prior series investigated the expression of prepro-gastrin releasing peptide (prepro-GRP) in the peripheral blood of lung cancer patients. Our aim was to assess any prepro-GRP role as a prognostic factor for small cell lung cancer (SCLC) and NSCLC and correlations with clinical presentation and treatment outcome. Methods: A prospective study was conducted during the time period from the beginning of January 2012 till the end of January 2014. Prepro-GRP expression was analysed using a nested RT-PCR assay in peripheral blood of 62 untreated lung cancer patients attending the National Cancer Institute (NCI), Cairo University, and 30 age and sex matched healthy volunteers. Results: Among the 62 lung cancer cases, there were 24 (38.7%) SCLC, and 38 (61.3%) NSCLC (10 squamous cell carcinomas, 12 adenocarcinomas, 11 large cell carcinomas, 4 undifferentiated carcinomas, and 1 adenosquamous carcinoma). Twenty six patients (41.9%) were prepro-GRP positive. Prepro-GRP expression was higher (58.3%) among SCLC patients compared to NSCLC (squamous cell carcinoma (15.4%), large cell carcinoma (36.4%), and adenocarcinoma (25%)). Mean OS among prepro-GRP negative cases was longer than that among preprogastrin positive cases (17.6 vs 14.9 months). The mean PFS durations among preprogastrin negative versus positive cases were 7.7 vs 4.6 months (p= 0.041). No difference in response to chemotherapy was identified between the groups (p=0.983). Conclusion: Prepro-GRP is suggested to be a useful prognostic marker for lung cancer patients, especially with the fast- growing, bad prognostic SCLC type. More studies should aim at detailed understanding of the mechanisms of prepro-GRP action and its use in monitoring the response to treatment in a larger cohort.  相似文献   
87.
ObjectiveThe aim of this study was to evaluate the effect of dilute HCl as a sodium removal treatment of grit blasted/NaOH/heat treated cp titanium implants on the in vitro bioactivity and the in vivo interface shear resistance at different healing periods.MethodsCylindrical implants were machined from cp titanium bars. Half of the implants were blasted by AL2O3 particles followed NaOH/heat treatment. The other half received similar treatment except, dilute HCl was additionally used as a sodium removal treatment. Implants surfaces topography was characterized by AFM before and after immersion in simulated body fluid (SBF) for 3 and 7 days. The implants resistance to interfacial shear force was evaluated at 2, 4, and 8 weeks implantation periods in experimental rabbits.ResultsSodium removal treatment significantly increased surface roughness (Sa parameter), valley fluid retention index and surface area before and after immersion in SBF, however, it significantly decreased core fluid retention index. Calcium and phosphorus containing surface deposits, of larger surface area, were precipitated on implants received the sodium removal treatment after 3 and 7 days in SBF. The implant–bone interface resistance to shear force was significantly increased at 2 weeks healing period after the use of the sodium removal treatment.SignificanceThe sodium removal treatment showed to be effective in improving the early bone–implant interface resistance to shear force. Topographical changes, after dilute HCl etching, seem to contribute to the different in vitro and/or in vivo responses observed.  相似文献   
88.

Objective

The aim of this study was to investigate the effect of dentin dryness on the variation in the probed nano-scale adhesion force between an AFM silicon nitride tip and demineralized intertubular dentin collagen fibrils network surface.

Methods

Dentin specimens were etched with 37% phosphoric acid for 15 s and then divided into three groups. Specimens of the first two groups were air-dried for 5 or 10 s (DH5s and DH10s), respectively, whereas specimens of the third group were left in the hydrated condition (H). For each group, Force curves were characterized by contact-mode AFM and the adhesion force (Fad) was calculated. The structure of the demineralized collagen fibrils network was characterized by tapping mode AFM. The tensile bond strength (TBS) to dentin was evaluated using one alcohol-based dentin self-priming adhesive. The dentin/resin interface was investigated by SEM.

Results

Dentin specimens in the wet-hydrated condition (H) showed significantly higher adhesion force and TBS values than dry-dehydrated specimens (DH5s and DH10s). AFM images showed open collagen fibrils network structure in wet-hydrated specimens (H), while the dry-dehydrated specimens (DH5s and DH10s) showed a collapsed appearance to varying degrees. SEM images revealed minimum resin infiltration in dry-dehydrated specimens.

Significance

The nano-scale adhesion force between the AFM probe and demineralized intertubular dentin surface was shown to be sensitive to surface air-drying. The decrease in the nano-scale adhesion force with the increase in the time of air-dryness is related to dehydration of the demineralized collagen fibrils network surface.  相似文献   
89.
Familial Mediterranean fever (FMF) is a hereditary inflammatory disorder transmitted as an autosomal recessive trait. It predominantly affects people living in, or originating from, areas around the Mediterranean and was difficult to diagnose until mutations in the MEFV gene were identified. This study aims to analyse the five most common MEFV mutations in Egyptian patients diagnosed clinically as FME Thirty-eight unrelated patients were tested for the presence of the MEFV gene mutations V726A, M694V, M694I, M680I and E148Q, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and the amplification refractory mutation system (ARMS). Twenty-three patients (60.5%) had one or more mutations, whereas no mutation was found in the remaining 15 patients (39.5%). The most common mutation was M694I (42.5%), followed by V726A (22.5%), M680I (17.5%) and E148Q (17.5%). The M694V mutation was not detected. The profile of MEFV gene mutations in this study suggests that the origin of FMF in Egypt is heterogeneous, a finding in concordance with that for other Arab populations; however, some differences were observed as M694V, the most common mutation reported in Arabs, was not detected in this study.  相似文献   
90.
PURPOSE: The aim of this study was to evaluate the effect of using 5.25% commercial sodium hypochlorite treatment prior to the application of etch-and-rinse and self-etching adhesives on dentin surface microtopography and tensile bond strength. MATERIALS AND METHODS: Thirty-two noncarious, nonrestored human third molars were collected. The occlusal enamel of all teeth was removed using diamond disks to expose flat dentin surfaces. The exposed dentin surfaces were abraded using 600-grit SiC disks, to create a uniform dentin smear layer. For AFM characterization, 12 teeth were equally divided into 4 groups according to the proposed dentin surface treatment. Three dentin disks, 2 mm thick, were evaluated per group using tapping mode assessment. Twenty teeth were used for TBS and SEM evaluation and were equally divided into 4 groups, according to the proposed dentin surface treatment. For TBS, 8 dentin/composite slabs, 2 mm thick, were used in each group, while for SEM evaluation 2 slabs were used. Each slab was tested in tension at a crosshead speed of 0.5 mm/min until failure occurred. The samples were examined using SEM operated at 30 kv to evaluate the hybrid layer photographically at 1500X. Statistical analysis was carried out using StatsDirect 2.5.7. One-way ANOVA followed by Tukey-Kramer multiple-comparison post-hoc tests were performed to test the difference between roughness parameters and TBS between groups. RESULTS: Sodium hypochlorite followed by the application of 37% phosphoric acid significantly increased the arithmetic average of the absolute values of surface height deviations (Sa), the surface area ratio which expresses the ratio between the surface area (taking the z height into account) and the area of the flat x,y plane (Sdr), and the surface bearing index (Sbi) parameters, while the application of sodium hypochlorite prior to the application of the self-etching primer significantly increased the valley fluid retention index (Svi) parameter. Self-etching primer without sodium hypochlorite pretreatment significantly increased the core fluid retention index (Sci) parameter. Sodium hypochlorite/AdheSE (7.42 +/- 2.16 MPa) significantly increased TBS value compared to other groups. However, no statistically significant difference was found between sodium hypochlorite/Excite (4.68 +/- 1.26 MPa), AdheSE (4.42 +/- 1.36), and Excite (4.06 +/- 1.35). Remnants of smear layer were detected with areas devoid of resin tags in SEM images of samples bonded with AdheSE self-etching adhesive, in contrast to samples bonded with sodium hypochlorite followed by AdheSE self-etching adhesive. CONCLUSION: The application of 5.25% commercial sodium hypochlorite with rubbing action for 60 s (total application time 120 s) seems to positively influence the TBS of the self-etching adhesive; however, it has no significant effect on TBS of etch-and-rinse single-bottle adhesive to dentin. The addition of functional roughness parameters to study the dentin surface was shown to be of importance in evaluating the relationship between bond strength and surface topography of conditioned dentin.  相似文献   
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