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101.
Nehal Elkhoshkhany Samir Marzouk Mohammed El-Sherbiny Heba Ibrahim Bozena Burtan-Gwizdala Mohammed S. Alqahtani Khalid I. Hussien Manuela Reben El Sayed Yousef 《Materials》2022,15(15)
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection. 相似文献
102.
A fluorescent curcumin-based Zn(II)-complex reactivates mutant (R175H and R273H) p53 in cancer cells
Alessia Garufi Daniela Trisciuoglio Manuela Porru Carlo Leonetti Antonella Stoppacciaro Valerio D’Orazi Maria Laura Avantaggiati Alessandra Crispini Daniela Pucci Gabriella D’Orazi 《Journal of experimental & clinical cancer research : CR》2013,32(1):72
Background
Mutations of the p53 oncosuppressor gene are amongst the most frequent aberration seen in human cancer. Some mutant (mt) p53 proteins are prone to loss of Zn(II) ion that is bound to the wild-type (wt) core, promoting protein aggregation and therefore unfolding. Misfolded p53 protein conformation impairs wtp53-DNA binding and transactivation activities, favouring tumor growth and resistance to antitumor therapies. Screening studies, devoted to identify small molecules that reactivate mtp53, represent therefore an attractive anti-cancer therapeutic strategy. Here we tested a novel fluorescent curcumin-based Zn(II)-complex (Zn-curc) to evaluate its effect on mtp53 reactivation in cancer cells.Methods
P53 protein conformation was examined after Zn-curc treatment by immunoprecipitation and immunofluorescence assays, using conformation-specific antibodies. The mtp53 reactivation was evaluated by chromatin-immunoprecipitation (ChIP) and semi-quantitative RT-PCR analyses of wild-type p53 target genes. The intratumoral Zn-curc localization was evaluated by immunofluorescence analysis of glioblastoma tissues of an ortothopic mice model.Results
The Zn-curc complex induced conformational change in p53-R175H and -R273H mutant proteins, two of the most common p53 mutations. Zn-curc treatment restored wtp53-DNA binding and transactivation functions and induced apoptotic cell death. In vivo studies showed that the Zn-curc complex reached glioblastoma tissues of an ortothopic mice model, highlighting its ability to crossed the blood-tumor barrier.Conclusions
Our results demonstrate that Zn-curc complex may reactivate specific mtp53 proteins and that may cross the blood-tumor barrier, becoming a promising compound for the development of drugs to halt tumor growth. 相似文献103.
A total of 3179 patients were screened for Y-chromosome microdeletions and 821 patients for partial AZFc deletions. Thirty-nine Y-chromosomal microdeletions were found (2.4% of men with <1 x 10(6)/ml spermatozoa): two AZFa, two AZFb, one AZFbc, one partial AZFb, one partial AZFb+c and 32 AZFc (b2/b4). Partial AZFc deletions were found in 45 patients (5.5%), mostly gr/gr deletions (n = 28). In patients with AZFc deletion, azoospermia was found in 53.1% and sperm concentrations of mostly <0.1 x 10(6)/ml were found in 46.9%. Semen analyses and FSH measurements showed no trend over time. Elongated spermatids were seen in 6/15 AZFc patients and bilateral Sertoli cell-only was found in 4/15. Testicular sperm extraction (TESE) was attempted in 10 patients and spermatozoa were found in six. Compared with infertile men matched by sperm concentration, no differences in hormonal and seminal parameters could be found in patients with AZFc or gr/gr deletions. It is concluded that: (i) frequency of AZF deletions in Germany is much lower than in other countries; (ii) AZFc deletions are associated with severe disturbances of spermatogenesis and TESE is not possible in half of these patients; (iii) AZFc and gr/ gr deletions are not associated with any clinical diagnostic parameter; (iv) and no trend is apparent over time. 相似文献
104.
Plotti G Plotti F Di Giovanni A Battaglia F Nagar G 《Journal of minimally invasive gynecology》2008,15(2):166-171
STUDY OBJECTIVE: Classic myomectomy was performed via laparotomy. More recently, laparoscopic myomectomy has become a valuable treatment option. Vaginal myomectomy is a surgical procedure that has recently been evaluated. However, few trials have been reported in past literature. The aim of this study was to evaluate feasibility and complication rate of patients submitted to vaginal myomectomy. DESIGN: Prospective study with review of literature (Canadian Task Force classification II-2). SETTING: Department of Obstetrics and Gynecology, S. Filippo Neri Hospital of Rome, Italy. PATIENTS: Consecutive patients with symptomatic myomas who refused hysterectomy. INTERVENTIONS: After preoperative assessment, patients were submitted to vaginal myomectomy using posterior colpotomy. MEASUREMENTS AND MAIN RESULTS: Operative time, perioperative complications, and hospital stay were prospectively recorded. Follow-up examinations were performed at 1 and 12 months postoperatively. Data on possible symptoms, fertility, and pregnancy outcome during follow-up periods were recorded. Myomectomy was completed vaginally in 17 (94%) of 18 patients. Mean operating time was 48 +/- 22 minutes; mean operative blood loss and hospital stay were 210 +/- 350 mL and 3.5 +/- 2.4 days, respectively. Only 2 (11%) patients required blood transfusion. Three patients have conceived spontaneously. CONCLUSION: Vaginal myomectomy is a feasible and safe surgical procedure, with low morbidity and short hospital stay, and could represent a valid alternative to open or laparoscopic myomectomy in selected cases. 相似文献
105.
AIM: To analyze the management of newborns after major surgery receiving morphine subcutaneously and to identify possible side effects. METHODS: Morphine was administered via a subcutaneous catheter (Insuflon) in 20 newborns after major surgery. Side effects like hypotension, pain during morphine administration and local infection were noted. Morphine dose was adjusted according to the hospital guidelines with the Neonatal Infant Pain Score (NIPS) and the Finnegan withdrawal score. RESULTS: Surgery was performed at the median age of 38 5/7 weeks (range: 32 1/7-49 5/7 weeks). Before starting subcutaneous morphine administration, patients received intravenous morphine for a median of two weeks (range six days to seven weeks). All patients showed good pain relief with no severe side effects. Three patients reacted with crying to the first dose of subcutaneous morphine. No other side effects occurred. CONCLUSION: Subcutaneous application of morphine with the Insuflon catheter is an alternative to intravenous treatment of postoperative pain in neonates. In this small group pain relief was good and side effects were harmless. 相似文献
106.
Paradisi R Fabbri R Battaglia C Facchinetti F Venturoli S 《Fertility and sterility》2007,88(3):744-748
The aim of this study was to evaluate the systemic production of nitric oxide (NO) in missed and threatened abortion and in nonpregnant and regular pregnant controls with the purpose of defining its role in the mechanisms regulating the first-trimester pregnancy toward either positive or negative evolution. Patients with missed abortion showed serum NO levels clearly decreased compared with nonpregnant patients and patients with regular pregnancy and threatened abortion, supporting a direct functional role of the NO mediator in early embryonic development and confirming its importance in the uterus and cervix during abortion. 相似文献
107.
Sylvia J. Gasparini Karen Tessmer Miriam Reh Stephanie Wieneke Madalena Carido Manuela Vlkner Oliver Borsch Anka Swiersy Marta Zuzic Olivier Goureau Thomas Kurth Volker Busskamp Günther Zeck Mike O. Karl Marius Ader 《The Journal of clinical investigation》2022,132(12)
Once human photoreceptors die, they do not regenerate, thus, photoreceptor transplantation has emerged as a potential treatment approach for blinding diseases. Improvements in transplant organization, donor cell maturation, and synaptic connectivity to the host will be critical in advancing this technology for use in clinical practice. Unlike the unstructured grafts of prior cell-suspension transplantations into end-stage degeneration models, we describe the extensive incorporation of induced pluripotent stem cell (iPSC) retinal organoid–derived human photoreceptors into mice with cone dysfunction. This incorporative phenotype was validated in both cone-only as well as pan-photoreceptor transplantations. Rather than forming a glial barrier, Müller cells extended throughout the graft, even forming a series of adherens junctions between mouse and human cells, reminiscent of an outer limiting membrane. Donor-host interaction appeared to promote polarization as well as the development of morphological features critical for light detection, namely the formation of inner and well-stacked outer segments oriented toward the retinal pigment epithelium. Putative synapse formation and graft function were evident at both structural and electrophysiological levels. Overall, these results show that human photoreceptors interacted readily with a partially degenerated retina. Moreover, incorporation into the host retina appeared to be beneficial to graft maturation, polarization, and function. 相似文献
108.
Solaro C Messmer Uccelli M Brichetto G Augello G Taddei G Boccardo F Buffoni F Campisi C Lopes L Battaglia MA Mancardi GL 《Multiple sclerosis (Houndmills, Basingstoke, England)》2006,12(5):659-661
The aim of the study was to evaluate the frequency of oedema of the lower limbs in multiple sclerosis (MS) patients utilizing a multidisciplinary approach. A total of 205 patients with definite MS were included in the study. Seventy-five were male and 130 female, with a mean age of 50.53, mean Expanded Disability Status Scale (EDSS) score of 5.27 and mean disease duration of 16.6 years. Seventy-one patients had a relapsing-remitting (RR) disease course, 85 were secondary progressive (SP) and 49 were primary progressive (PP). Ninety-three patients (45%) showed oedema at the examination. EDSS, disease duration and disease course, but not gender, were statistically different between oedema and non-oedema patients. Out of 93 patients with oedema, 69 agreed to undergo a vascular examination. Of 69 patients, 45 (65.2%) had a CEAP score (specific rating scale for oedema) of 3 (presence of oedema) and 24 (34.8%) had a score of 4 (presence of a trophic disorder). Out of 69 subjects, 33 agreed to undergo a lymphoscintigraphy, which was normal in only 29 extremities out of 66. Lower limb oedema is common in MS patients, especially in those with reduced mobility. Early screening is advised in patients with an elevated EDSS. 相似文献
109.
Georgiana-Emmanuela Gilca-Blanariu Anca Trifan Manuela Ciocoiu Iolanda Valentina Popa Alexandru Burlacu Gheorghe G. Balan Andrei Vasile Olteanu Gabriela Stefanescu 《Nutrients》2022,14(9)
The altered magnesium status in inflammatory bowel disease (IBD) patients may have a significant clinical imprint considering its role in cell signaling and genomic stability, as well as its involvement in IBD patients’ fatigue. Our study pioneers the investigation of magnesium hair concentration patterns in an adult population of IBD patients. The hair magnesium concentration in IBD patients is compared to healthy controls in order to identify correlations between the magnesium status and relevant parameters related to disease activity, psychological status, and sleep quality. We report a significantly lower hair magnesium concentration within the IBD group compared to healthy controls (95%CI: 0.006–0.062; p = 0.017) and lower levels in CD compared to UC (95%CI: −0.061–−0.002; p = 0.038). We identified a borderline statistical significance between the hair magnesium concentration and UC disease activity (95%CI; −0.679–0.008; p = 0.055) and a significantly lower magnesium concentration in patients who reported increased sleep latency (95%CI −0.65–−0.102; p = 0.011) or decreased sleep duration (95%CI −0.613–−0.041; p = 0.028). Our results advance several hypotheses with substantial clinical impact to be confirmed in future studies. Magnesium levels appear to be modified in IBD patients, which suggests it either plays a primary role in disease pathophysiology or a is result of the disease’s evolution. Magnesium could be used in predictive models for clinical/subclinical disease activity. Moreover, magnesium supplementation may improve IBD evolution and sleep quality for patients with a deficit of this mineral. However, confirmatory evidence-based studies are needed to generate specific dosing, time of supplementation, and optimum monitoring of magnesium status in IBD patients. 相似文献
110.
Sebastian Wiedl Peter Karlinger Michael Schemme Manuela List Holger Ruckdschel 《Materials》2022,15(9)
The necessity for resource-efficient manufacturing technologies requires new developments within the field of plastic processing. Lightweight design using wood fibers as sustainable reinforcement for thermoplastics might be one solution. The processing of wood fibers requires special attention to the applied thermal load. Even at low processing temperatures, the influence of the dwell time, temperature and shear force is critical to ensure the structural integrity of fibers. Therefore, this article compares different compounding rates for polypropylene with wood fibers and highlights their effects on the olfactory, visual and mechanical properties of the injection-molded part. The study compares one-step processing, using an injection-molding compounder (IMC), with two-step processing, using a twin-scew-extruder (TSE), a heating/cooling mixer (HCM) and an internal mixer (IM) with subsequent injection molding. Although the highest fiber length was achieved by using the IMC, the best mechanical properties were achieved by the HCM and IM. The measured oxidation induction time and volatile organic compound content indicate that the lowest amount of thermal damage occurred when using the HCM and IM. The advantage of one-time melting was evened out by the dwell time. The reinforcement of thermoplastics by wood fibers depends more strongly on the structural integrity of the fibers compared to their length and homogeneity. 相似文献