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991.
992.
Contaldi Elena Magistrelli Luca Gallo Silvia Comi Cristoforo 《Neurological sciences》2022,43(8):4769-4776
Neurological Sciences - Dopamine is involved in sexual behavior, but dopaminergic imaging studies establishing the relationship between nigrostriatal dopaminergic degeneration and sexual... 相似文献
993.
Carlos Eduardo Bezerra Moura Naisandra Bezerra Silva Juliana Carvalho Sa Geraldo Barroso Cavalcanti Junior Silvia Regina Batistuzzo de Medeiros Hugo Alexandre Oliveira Rocha Paula Carvalho Papa Clodomiro Alves Jr 《Artificial organs》2016,40(5):497-504
To evaluate the effect of topography in nanoscale, titanium surfaces were bombarded by argon ions (a chemically inert gas), in an atmosphere of plasma. The effects of surface parameters on morphology, adhesion, proliferation, and MC3T3‐E1 preosteoblasts differentiation were analyzed. Nontreated (smooth) surfaces were used as a control. The levels of average roughness (Ra) observed in bombarded and smooth titanium surfaces were of 95 and 14 nm, respectively. The wettability increased on treated surfaces. The number of attached cells (30 and 60 min) was significantly higher on the bombarded surface. The cell proliferation after 3 and 7 days was also significantly higher on the ion‐bombarded surface. In addition, the ALP activity and expression of osteocalcin were higher in cells grown on the treated surface. The results showed that bombardment with argon ions increased the roughness and the wettability of the Ti surface, promoting a significant increase in the adhesion, proliferation, and differentiation of preosteoblasts. 相似文献
994.
Background
Previous reports have described several candidates, which have the potential to replace colonoscopy, but to date, there is still no device capable of fully replacing flexible colonoscopy in the management of colonic disorders and for mass adult population screening for asymptomatic colorectal cancer.Materials and methods
NASA developed the TRL methodology to describe and define the stages of development before use and marketing of any device. The definitions of the TRLS used in the present review are those formulated by “The US Department of Defense Technology Readiness Assessment Guidance” but adapted to micro-robots for colonoscopy. All the devices included are reported in scientific literature. They were identified by a systematic search in Web of Science, PubMed and IEEE Xplore amongst other sources. Devices that clearly lack the potential for full replacement of flexible colonoscopy were excluded.Assessment of the current situation
The technological salient features of all the devices included for assessment are described briefly, with particular focus on device propulsion. The devices are classified according to the TRL criteria based on the reported information. An analysis is next undertaken of the characteristics and salient features of the devices included in the review: wireless/tethered devices, data storage–transmission and navigation, additional functionality, residual technology challenges and clinical and socio-economical needs.Conclusions
Few devices currently possess the required functionality and performance to replace the conventional colonoscopy. The requirements, including functionalities which favour the development of a micro-robot platform to replace colonoscopy, are highlighted.995.
996.
Rodrigo M. Rocha Pâmela C. M. Delvas Zanni Patrícia de Souza Bonfim-Mendonça Fabrícia Gimenes Silvia S. Dantas Alczuk Terezinha I. Estivalet Svidzinski Márcia E. Lopes Consolaro 《International urogynecology journal》2016,27(5):773-780
Introduction and hypothesis
Acute uncomplicated lower urinary tract infections (UTI) and vulvovaginal candidiasis (VVC) both occur frequently in women. Although VVC is believed to commonly occur after antibiotic therapy, few studies have demonstrated this association. Thus, the aim of the study was to estimate the prevalence of colonization by Candida spp. and VVC after norfloxacin (NOR) use for UTI and the effects on the vaginal microbiota and inflammatory process.Methods
This was a prospective cohort study of women with culture-proven UTI who were treated with NOR (antibiotic group). The control group consisted of women with noninfectious diseases or in preventive care. Candida vaginal infections were monitored both clinically and mycologically at baseline and at the follow-up evaluation.Results
All women showed UTI remission after NOR treatment, and no woman in either group, antibiotic and control, showed symptoms of VVC. Both groups showed similar ratios of a positive Candida culture at baseline (6.7 % and 12.8 %, respectively) and at follow-up (3.3 % and 8.5 %, respectively) (p?=?0.2768 and p?=?0.5035, respectively). The antibiotic group showed no increased risk of Candida colonization or VVC after NOR treatment compared with the control group [odds ratio (OR) 0.556, 95 % confidence interval (CI) 0.2407–10.05].Conclusions
NOR was effective for UTI treatment, did not increase the risk of vaginal colonization by Candida or VVC, and did not lead to major disturbances of the vaginal microbiota.997.
Laurent de Landsheere Mathias Brieu Silvia Blacher Carine Munaut Betty Nusgens Chrystèle Rubod Agnès Noel Jean-Michel Foidart Michelle Nisolle Michel Cosson 《International urogynecology journal》2016,27(4):629-635
Introduction and hypothesis
The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP).Methods
Tissue samples were collected from the anterior [point Ba; POP Questionnaire (POP-Q)] and/or posterior (point Bp; POP-Q) vaginal wall of 15 women who underwent vaginal surgery for POP. Both histological and biomechanical assessments were performed from the same tissue samples in 14 of 15 patients. For histological assessment, the density of collagen and elastin fibers was determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. For biomechanical testing, uniaxial tension tests were performed to evaluate vaginal tissue stiffness at low (C0) and high (C1) deformation rates.Results
Biomechanical testing highlights the hyperelastic behavior of the vaginal wall. At low strains (C0), vaginal tissue appeared stiffer when elastin density was low. We found a statistically significant inverse relationship between C0 and the elastin/collagen ratio (p?=?0.048) in the lamina propria. However, at large strain levels (C1), no clear relationship was observed between elastin density or elastin/collagen ratio and stiffness, likely reflecting the large dispersion of the mechanical behavior of the tissue samples.Conclusion
Histological and biomechanical properties of the vaginal wall vary from patient to patient. This study suggests that elastin density deserves consideration as a relevant factor of vaginal stiffness in women with POP.998.
Andrea?Amaroli Silvia?Ravera Steven?Parker Isabella?Panfoli Alberico?Benedicenti Stefano?BenedicentiEmail author 《Lasers in medical science》2016,31(4):741-747
Photobiomodulation is proposed as a non-linear process, and only low-level laser therapy (LLLT) is assumed to stimulate exposed cells, whereas high powered laser and fluences can cause negative effects, exhausting the cell’s energy reserve as a consequence of excessive photon-based stimulation. In our work, we investigated and compared the effects of 808-nm diode laser (CW) with a new flat-top handpiece. To this purpose, we tested the photobiomodulation effects of 1 and 3 J/cm2 fluence, both generated by 100 mW or 1 W of laser power and of 64 J/cm2 of fluence generated by 100 mW, 1 W, 1.5 W or 2 W, as expressed through oxygen consumption and ATP synthesis of Paramecium. Data collected indicates the incremental consumption of oxygen through irradiation with 3 J/cm2–100 mW or 64 J/cm2–1 W correlates with an increase in Paramecium ATP synthesis. The Paramecium respiration was inhibited by fluences 64 J/cm2–100 mW or 64 J/cm2–2 W and was followed by a decrease in the endogenous ATP concentration. The 1 J/cm2–100 mW or 1 W and 3 J/cm2–1 W did not affect mitochondrial activity. The results show that the fluence of 64 J/cm2–1 W more than the 3 J/cm2–100 mW causes greater efficiency in Paramecium mitochondria respiratory chain activity. Our results suggest that thanks to flat-top handpiece we used, high fluences by high-powered laser have to be reconsidered as an effective and non-invasive therapy. Possible associated benefits of deeper tissue penetration would increase treatment effectiveness and reduced irradiation time. 相似文献
999.
Christopher M. Kuenze Silvia S. Blemker Joseph M. Hart 《Journal of orthopaedic research》2016,34(9):1656-1662
It remains unclear what role reduced volume and cross‐section area (CSA) of individual quadriceps muscles may play in persistent quadriceps weakness and more global dysfunction following ACL reconstruction (ACLR). The purpose of this investigation was to establish the relationship between cross‐sectional area of the quadriceps muscle group and measures of knee related and quadriceps function following ACLR. Thirty participants with a history of primary, unilateral ACLR experiencing persistent quadriceps activation failure participated in this cohort study. Clinical factors including International Knee Documentation Committee (IKDC) score, normalized knee extension MVIC torque (Nm/kg) and quadriceps central activation ratio (CAR, %) were assessed in addition to CSA. Quadriceps CSA was measured via magnetic resonance imaging (MRI; Siemens Avanto 1.5T). Quadriceps CSA (cm2) and quadriceps volume (cm3) as well as individual muscle estimates were identified within a 10 cm mid‐thigh capture area. Pearson's product‐moment correlation coefficients (r) established relationships between CSA and all other variables. Stepwise linear regression established which CSA factors were able to successfully predict clinical factors. Knee extension MVIC torque was strongly correlated with Vastus Intermedius (VI; r = 0.857, p < 0.001) CSA as well as partial VI (r = 0.849, p < 0.001) and quadriceps (r = 0.830, p < 0.001) volume. Partial VI (r = 0.365, p = 0.047) volume was weakly correlated with IKDC score. Knee extension MVIC torque was strongly predicted using VI CSA alone (R2 = 0.725) or in combination with Vastus Medialis CSA (VM; R2 = 0.756). Statement of Clinical Significance: Atrophy of the VI and VM muscles negatively impacts knee extension strength following ACLR. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1656–1662, 2016. 相似文献
1000.
Sclerostin Expression in Bile Ducts of Patients With Chronic Cholestasis May Influence the Bone Disease in Primary Biliary Cirrhosis 下载免费PDF全文
Núria Guañabens Silvia Ruiz‐Gaspà Laia Gifre Pilar Peris Ana Monegal Marta Dubrueil Ana Arias Albert Parés 《Journal of bone and mineral research》2016,31(9):1725-1733
Sclerostin is involved in the regulation of osteoblastogenesis and little is known about its role in the development of bone disease in primary biliary cirrhosis (PBC), characterized by low bone formation. Therefore, we have assessed the circulating levels and the liver expression of sclerostin in this cholestatic disease. Serum sclerostin levels were measured in 79 women with PBC (mean age 60.6 ± 1.2 years) and in 80 control women. Lumbar and femoral bone mineral density (BMD), as well as parameters of mineral metabolism and bone remodeling, were measured. Moreover, sclerostin gene (SOST) expression in the liver was assessed by real‐time PCR in samples of liver tissue taken by biopsy in 11 PBC patients and in 5 normal liver specimens. Presence and distribution of sclerostin was evaluated in liver slices from 11 patients by immunohistochemistry. The severity of histologic lesions was assessed semiquantitatively in the same liver samples. PBC patients had higher sclerostin levels than controls (75.6 ± 3.9 versus 31.7 ± 1.6 pmol/L, p < 0.001). Serum sclerostin correlated inversely with markers of bone formation and resorption. Sclerostin mRNA in the liver was overexpressed compared with control samples (2.7‐fold versus healthy liver). Sclerostin was detected by immunohistochemistry in 7 of the 11 liver samples, mainly located in the bile ducts. Liver sclerostin was associated with the severity of cholangitis (p = 0.02) and indirectly with the degree of lobular inflammation (p = 0.03). Sclerostin mRNA expression was higher in samples that tested positive by immunohistochemistry and particularly in those with lobular granuloma (p = 0.02). The increased expression of sclerostin in the liver and the association with histologic cholangitis may explain the high serum levels of this protein in patients with PBC, thus suggesting that sclerostin may influence the decreased bone formation in this cholestatic disease. © 2016 American Society for Bone and Mineral Research. 相似文献