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31.
The need for a better understanding of cell behavior and for exploiting cell functions in various healthcare applications has driven biomedical research to develop increasingly complex fabrication strategies to reproduce the natural biological microenvironment in vitro. Different approaches have led to the development of refined examples of 2- and 3-D structures able to sustain cellular proliferation, differentiation and functionality very similar to those normally occurring in living organisms. One such approach is two-photon polymerization. In this paper, we present a trabecula-like structure (which we have named “Osteoprint”) that resembles to the typical microenvironment of trabecular bone cells. Starting from microtomography images of the trabecular bone, we prepared several Osteoprints through two-photon polymerization and tested the behavior of SaOS-2 bone-like cells cultured on our structures. Interestingly, we found that Osteoprints deeply affect cellular behavior, determining an exit from the cell cycle and an enhancement of osteogenic differentiation. Indeed, we found an up-regulation of the genes involved in SaOS-2 cell maturation and an increase in hydroxyapatite production and accumulation upon SaOS-2 culture on the Osteoprints. The findings we obtained are extremely interesting, and open up new perspectives in “bioinspired” approaches for tissue engineering and regenerative medicine.  相似文献   
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Two series of piperazinyl-pyrrolo[1,2-a]quinoxaline derivatives were prepared via a Buchwald–Hartwig cross-coupling reaction and then evaluated for their ability to inhibit the drug efflux activity of CaCdr1p and CaMdr1p transporters of Candida albicans overexpressed in a Saccharomyces cerevisiae strain. In the initial screening of twenty-nine piperazinyl-pyrrolo[1,2-a]quinoxaline derivatives, twenty-three compounds behaved as dual inhibitors of CaCdr1p and CaMdr1p. Only four compounds showed exclusive inhibition of CaCdr1p or CaMdr1p. Further biological investigations were developed and for example, their antifungal potential was evaluated by measuring the growth of control yeast cells (AD1-8u) and efflux pump-overexpressing cells (AD-CDR1 and AD-MDR1) after exposition to variable concentrations of the tested compounds. The MIC80 values of nineteen compounds ranging from 100 to 901 μM for AD-CDR1 demonstrated that relative resistance index (RI) values were between 8 and 274. In comparison, only seven compounds had RI values superior to 4 in cells overexpressing Mdr1p. These results indicated substrate behavior for nineteen compounds for CaCdr1p and seven compounds for CaMdr1p, as these compounds were transported via MDR transporter overexpressing cells and not by the AD1-8u cells. Finally, in a combination assay with fluconazole, two compounds (1d and 1f) have shown a synergistic effect (fractional inhibitory concentration index (FICI) values ≤ 0.5) at micromolar concentrations in the AD-MDR1 yeast strain overexpressing CaMdr1p-protein, indicating an excellent potency toward chemosensitization.

Two series of piperazinyl-pyrrolo[1,2-a]quinoxaline derivatives were prepared via a Buchwald–Hartwig cross-coupling reaction and then evaluated for their ability to inhibit the drug efflux activity of two Candida albicans transporters.  相似文献   
34.
Objective. To evaluate the use of color-flow Doppler ultrasonography, a direct, noninvasive technique, for measurement of kidney blood flow in patients with systemic sclerosis (SSc). Methods. Twenty-five normal volunteers and 25 SSc patients (median disease duration 8 years, range 2–21 years) were studied. All were free of clinical symptoms of renal damage. The resistance index (RI) was determined on main, interlobar, and cortical vessels. Results. In SSc patients, the RI was significantly increased at every sampling site examined (P < 0.001). RI values were strongly correlated with disease duration (main artery r = 0.56, P < 0.04; interlobar artery r = 0.63, P < 0.02; cortical artery r = 0.75, P < 0.002). Regression analysis showed no relationship between RI and creatinine clearance values. Conclusion. Color-flow Doppler ultrasonography is a sensitive and noninvasive technique for evaluating vascular damage of the kidney in patients with SSc.  相似文献   
35.
36.
Neuromyelitis optica is a rare neurological autoimmune disorder characterized by a poor prognosis. Immunosuppression can halt disease progression, but some patients are refractory to multiple treatments, experiencing frequent relapses with accumulating disability. Here we report on durable clinical remissions after allogeneic hematopoietic stem cell transplantation in 2 patients suffering from severe forms of the disease. Immunological data evidenced disappearance of the pathogenic antibodies and regeneration of a naive immune system of donor origin. These findings correlated with evident clinical and radiological improvement in both patients, warranting extended clinical trials to investigate this promising therapeutic option. ANN NEUROL 2014;75:447–453  相似文献   
37.
Because of its similarity to ageing in impaired immune efficiency 48 h after surgical procedures on young partially hepatectomised mice, partial hepatectomy/liver regeneration (pHx) provides a good model for the study of inflammation in ageing. In old age, high metallothionein (I+II) (MT) sequesters a substantial number of intracellular zinc ions consequently leading to low zinc ion bioavailability for an adequate immune response. Corticosterone and IL-6 affect MTmRNA induction in inflammation and after pHx against oxidative damage. The aim of this study was to investigate the role played by MT in conferring immune plasticity in ageing and in very old age using the pHx model. 48 h after their partial hepatectomy, the crude zinc balance was negative in young, old and very old mice coupled with increased MT, corticosterone, sIL-6R and IL-6. Concomitantly, Natural Killer (NK) cell activity and IL-2 production decreased. Complete restoration of the nutritional-endocrine-immune parameters occurred 15 days from the surgical procedures in young and very old mice, but not in old or transgenic mice overexpressing MT. A significant positive or inverse correlation among nutritional-endocrine-immune parameters exists in young and very old mice, but not in old mice during liver regeneration. Since MT also affects c-myc, the gene expression of c-myc declines from 48 h to days 7 and 15 after pHx in young and very old mice, but remains constantly high in old pHx mice for the same days. This circumstance leads to the appearance of tumours in the long run in old pHx mice and survival times that are shorter than old sham controls. Because complete remodelling also occurs in IL-6 and in sIL-6R in very old mice during liver regeneration, the pre-existing inflammation is not detrimental in very old age. As such, very old mice are still responsive to large inflammation, such as pHx, thanks to correct MT homeostasis. Correct MT homeostasis, via c-myc, is therefore pivotal in both suitable liver regeneration and in conferring immune plasticity with subsequent successful ageing. High MT plays an extremely harmful role in ageing: on one hand it lowers zinc ion bioavailability levels required for immune efficiency and on the other hand it increases c-myc expression. The combination of immune depression and enhanced c-myc, via high MT, may trigger the appearance of age-related degenerative diseases.  相似文献   
38.
We report a modified post-transplant cyclophosphamide (PT-CY) regimen, for unmanipulated haploidentical marrow transplants, in 150 patients with acute myeloid leukemia (AML). All patients received a myeloablative regimen, cyclosporine A (CsA) on day 0, mycophenolate on day +1, and PT-CY 50?mg/kg on days +3 and +5. The median age was 51 (range, 17–74) years, 51 (34%) patients had active disease at transplant, and the median follow-up of surviving patients 903 (range, 150-1955) days. The cumulative incidence (CI) of engraftment, acute graft-versus-host disease (GVHD) grade II to IV, and moderate/severe chronic GVHD was 92%, 17%, and 15%, respectively. The 4-year CI of transplant-related mortality (TRM) and relapse was 20% and 24%, respectively. Four-year survival for remission patients was 72% (74% versus 67% for <60 or ≥60 years of age) and 26% for advanced patients (17% versus 41% for <60 or ≥60 years of age). In a multivariate analysis, active disease at transplant was the only negative predictor of survival, TRM and relapse. The original PT-CY regimen can be modified with CsA on day 0, still providing protection against GVHD, low toxicity, and encouraging low relapse incidence in AML patients, also over 60 years of age.  相似文献   
39.

Study Objective

To estimate the incidence of infection after diagnostic and operative hysteroscopic procedures performed in an in-office setting with different distension media (saline solution or CO2).

Design

Prospective, multicenter, observational study (Canadian Task Force classification II-2).

Setting

Tertiary women's health centers.

Patients

A total of 42,934 women who underwent hysteroscopy between 2015 and 2017.

Interventions

Of the 42,934 patients evaluated, 34,248 underwent a diagnostic intervention and 8686 underwent an operative intervention; 17,973 procedures used CO2 and 24,961 used saline solution as a distension medium. Patients were contacted after the procedure to record postprocedure symptoms suggestive of infection, including 2 or more of the following signs occurring within the 3 weeks after hysteroscopy: fever; lower abdominal pain; uterine, adnexal, or cervical motion tenderness; purulent leukorrhea; vaginal discharge or itchiness; and dysuria. Vaginal culture, clinical evaluation, transvaginal ultrasound, and histological evaluation were completed to evaluate symptoms.

Measurements and Main Results

Operative hysteroscopies comprised polypectomies (n?=?7125; 82.0%), metroplasty (n?=?731; 15.0%), myomectomy (n?=?378; 7.8%), and tubal sterilization (n?=?194; 4.0%). Twenty-five of the 42,934 patients (0.06%) exhibited symptoms of infection, including 24 patients (96%) with fever, 11 (45.8%) with fever as a single symptom, 7 (29.2%) with fever with pelvic pain, and 10 (41.7%) with fever with dysuria. In 5 patients with fever and pelvic pain, clinical examination and transvaginal ultrasound revealed monolateral or bilateral tubo-ovarian abscess. In these patients, histological examination from surgical specimens revealed the presence of endometriotic lesions.

Conclusion

The present study suggests that routine antibiotic prophylaxis is not necessary before hysteroscopy because the prevalence of infections following in-office hysteroscopy is low (0.06%).  相似文献   
40.
Aim: To evaluate sensitivity to different probiotics in children with cow's milk allergy.
Methods: Eighty-five patients (age range: 4 months –12 years) presenting atopic dermatitis (AD) were enrolled. Skin prick test (SPT) responses to three different probiotics preparations (Fiorilac®, Dicoflor® and Reuterin®) were evaluated in addition to relevant food allergens.
Results: Thirty-nine patients out of 85 (45.8%) had a positive skin response to prick test for cow's milk (3 with reaction <3 mm). Of the thirty-six patients with a cow's milk weal reaction >3 mm, twenty-eight (77.8%) had a skin response to Fiorilac®, four patients (11%) to Dicoflor® and four (11%) to Reuterin®. The proportion of SPT reaction to all the investigated probiotics preparations was significantly lower than cow's milk (r = 9.406; p = 0.002). A significantly higher sensitization was observed for Fiorilac® versus Dicoflor® (r = 30.916; p < 0.001) and versus Reuterin® (r = 34.133; p < 0.001).
Conclusion: Probiotic use in patients with cow's milk allergy has to be limited to products that do not contain milk. This should be clearly reported in the label. In selected patients, it is advisable to perform a screening SPT with the product to evaluate its potential contamination with milk.  相似文献   
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