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111.
Vincenzo Tosco Flavia Vitiello Michele Furlani Maria Laura Gatto Riccardo Monterubbianesi Alessandra Giuliani Giovanna Orsini Angelo Putignano 《Materials》2021,14(1)
This study aimed to compare two different bulk-filling techniques, evaluating the internal and external adaptation of class II resin-composite restorations, by analysing the gap formation using microcomputed tomography (µ-CT) and scanning electronic microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Two standardized mesio/disto-occlusal (MO/DO) cavities were prepared in eight extracted human third molars that were divided, according to the filling technique used, in the following two groups (n = 4): BG (Bulk&Go group) and BT (Bulk Traditional group). After universal bonding application, followed by the light curing, all teeth were restored using a bulk-fill composite. Specimens were scanned with µ-CT to evaluate 3D interfacial gaps. Acquired µ-CT data were analysed to quantify the gap formation. Complementary information to the µ-CT analysis were obtained by SEM. Thereafter, the chemical composition of tooth–restoration interface was analysed using EDS. The µ-CT analysis revealed gaps formation at the tooth–restoration interface for both the BG and BT groups, while within the restoration, only in the BT group there was evidence of microleakage formation. The scanning electron micrographs of both groups showed that the external marginal integrity of the restoration was preserved, while EDS showed the three different structures (tooth surface, adhesive layer and resin composite) of the tooth–restoration interface, highlighting the absence of gap formation. In both BG and BT, the two filling techniques did not show significant differences regarding the internal and external marginal adaptation of the restoration. To achieve a successful restoration, the clinician could be advised to restore a class II cavity using a single increment bulk-filling technique (BG), thus treating it as a class I cavity. 相似文献
112.
Zhai G Cicuttini F Srikanth V Cooley H Ding C Jones G 《Arthritis and rheumatism》2005,52(4):1069-1076
OBJECTIVE: To compare associations between anthropometric and lifestyle factors and femoral head cartilage volume/thickness and radiographic features of osteoarthritis (OA) and to provide evidence of construct validity for magnetic resonance imaging (MRI) assessment of femoral cartilage volume and thickness. METHODS: We studied a cross-sectional sample of 151 randomly selected subjects (79 men, 72 women; mean age 63 years) from the Tasmanian Older Adult Cohort Study. A sagittal T1-weighted fat-suppression MRI scan of the right hip was performed to determine femoral head cartilage volume, cartilage thickness, and size. An anteroposterior radiograph of the pelvis with weight bearing was performed and scored for radiographic evidence of OA in the right hip. Other factors measured were height, weight, leg strength, serum vitamin D levels, and bone mineral density. RESULTS: Hip cartilage volume was significantly associated with female sex, body mass index, and femoral head size, whereas hip cartilage thickness was significantly associated only with the size of the femoral head. Only female sex was significantly associated with the total radiographic OA score and the joint space narrowing (JSN) score, but not the osteophyte score. Radiographic JSN of the hip, especially axial JSN (but not osteophytes), was significantly correlated with hip cartilage volume and thickness. CONCLUSION: Femoral head cartilage volume and thickness have modest but significant construct validity when correlated with radiographic findings. Furthermore, the generally stronger associations with volume compared with radiographic OA suggest that MRI may be superior at identifying risk factors for hip OA. 相似文献
113.
Symptoms and pathophysiological correlations in patients with constipation and functional dyspepsia 总被引:5,自引:0,他引:5
Sarnelli G Grasso R Ierardi E De Giorgi F Savarese MF Russo L Budillon G Cuomo R 《Digestion》2005,71(4):225-230
INTRODUCTION: Patients with constipation often report dyspeptic symptoms, but whether constipation is associated with specific dyspeptic symptoms and altered gastrointestinal (GI) motility, remains to be established. Our aim was to study symptoms association and GI motility parameters in patients with constipation and functional dyspepsia. PATIENTS AND METHOD: 42 patients with different symptoms and severity of constipation and dyspepsia were enrolled. Scintigraphic gastric emptying, colonic transit time and gallbladder contraction were studied in all subjects. RESULTS: No significant association was observed between individual symptoms of constipation and dyspepsia. Patients with more severe constipation did not have higher dyspepsia severity scores. Colonic transit time, gastric half emptying and gallbladder contraction were not significantly correlated. Although patients with severe nausea had faster colonic transit than those with absent/mild symptom (19 +/- 2 vs. 48 +/- 7 h; p < 0.05), the multivariate analysis only revealed a significant association between severe postprandial fullness, delayed t1/2 (OR 1.05, CI 1-1.1) and impaired gallbladder contraction (OR 0.94, CI 0.89-0.99). CONCLUSIONS: Constipation was not associated with severity, or any particular dyspeptic symptom. Although motor abnormalities of both colon and proximal GI tract regions existed in the subset of constipated dyspeptic patients, they did not seem associated with the genesis of different dyspeptic symptoms. 相似文献
114.
Franco Onofri Silvia Giovedì Paola Vaccaro Andrew J. Czernik Flavia Valtorta Pietro De Camilli Paul Greengard Fabio Benfenati 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(22):12168-12173
Synapsin I is a synaptic vesicle-associated phosphoprotein that has been implicated in the formation of presynaptic specializations and in the regulation of neurotransmitter release. The nonreceptor tyrosine kinase c-Src is enriched on synaptic vesicles, where it accounts for most of the vesicle-associated tyrosine kinase activity. Using overlay, affinity chromatography, and coprecipitation assays, we have now shown that synapsin I is the major binding protein for the Src homology 3 (SH3) domain of c-Src in highly purified synaptic vesicle preparations. The interaction was mediated by the proline-rich domain D of synapsin I and was not significantly affected by stoichiometric phosphorylation of synapsin I at any of the known regulatory sites. The interaction of purified c-Src and synapsin I resulted in a severalfold stimulation of tyrosine kinase activity and was antagonized by the purified c-Src-SH3 domain. Depletion of synapsin I from purified synaptic vesicles resulted in a decrease of endogenous tyrosine kinase activity. Portions of the total cellular pools of synapsin I and Src were coprecipitated from detergent extracts of rat brain synaptosomal fractions using antibodies to either protein species. The interaction between synapsin I and c-Src, as well as the synapsin I-induced stimulation of tyrosine kinase activity, may be physiologically important in signal transduction and in the modulation of the function of axon terminals, both during synaptogenesis and at mature synapses. 相似文献
115.
OBJECTIVE: To describe the association between prevalent and incident knee cartilage defects and loss of knee cartilage in male and female adults. METHODS: A convenience sample of 325 subjects (mean age 45 years; age range 26-61 years) was evaluated at baseline and approximately 2 years later. Knee cartilage volume, cartilage defect scores (0-4 scale), and joint surface area were determined using T1-weighted fat-suppression magnetic resonance imaging techniques. Height, weight, and radiographic evidence of osteoarthritis were measured by standard protocols. RESULTS: Multivariable analysis revealed that baseline cartilage defect scores at the medial tibia, lateral tibia, and patella had a dose-response association with the annual rate of change in knee cartilage volume at the corresponding site (beta = -1.3% to -1.2% per grade; P < 0.05 for all comparisons). In addition, an increase in knee cartilage defect score (change of > or =1) was associated with higher rates of knee cartilage volume loss at all sites (beta = -1.9% to -1.7% per year; P < 0.01 for all comparisons). Furthermore, a decrease in the knee cartilage defect score (change of less than or equal to -1) was associated with an increase in knee cartilage volume at all sites (beta = 1.0% to 2.7% per year; P < 0.05 for all comparisons). CONCLUSION: Prevalent knee cartilage defects are predictive of compartment-specific cartilage loss over 2 years. Both increases and decreases in knee cartilage defects are associated with changes in knee cartilage volume, which implies a potential for reversal of knee cartilage loss. 相似文献
116.
Sera L. Young Albert H. J. Plenty Flavia A. Luwedde Barnabas K. Natamba Paul Natureeba Jane Achan Julia Mwesigwa Theodore D. Ruel Veronica Ades Beth Osterbauer Tamara D. Clark Grant Dorsey Edwin D. Charlebois Moses Kamya Diane V. Havlir Deborah L. Cohan 《Maternal and child health journal》2014,18(9):2044-2053
Household food insecurity (HHFI) may be a barrier to both optimal maternal nutritional status and infant feeding practices, but few studies have tested this relationship quantitatively, and never among HIV-infected individuals. We therefore described the prevalence of HHFI and explored if it was associated with poorer maternal nutritional status, shorter duration of exclusive breastfeeding (EBF) and fewer animal-source complementary foods. We assessed these outcomes using bivariate and multivariate analyses among 178 HIV-infected pregnant and breastfeeding (BF) women receiving combination antiretroviral therapy in the PROMOTE trial (NCT00993031), a prospective, longitudinal cohort study in Tororo, Uganda. HHFI was common; the prevalence of severe, moderate, and little to no household hunger was 7.3, 39.9, and 52.8 %, respectively. Poor maternal nutritional status was common and women in households experiencing moderate to severe household hunger (MSHH) had statistically significantly lower body mass index (BMIs) at enrollment (21.3 vs. 22.5, p < 0.01) and prior to delivery (22.6 vs. 23.8, p < 0.01). BMI across time during pregnancy, but not gestational weight gain, was significantly lower for MSHH [adjusted beta (95 % CI) ?0.79 (?1.56, ?0.02), p = 0.04; ?2.06 (?4.31, 0.19), p = 0.07], respectively. The prevalence (95 % CI) of EBF at 6 months was 67.2 % (59.7–73.5 %), and the proportion of women BF at 12 months was 80.4 % (73.3–85.7 %). MSHH was not associated with prevalence of EBF at 6 months or BF at 12 months. However, among those women still EBF at 4 months (81.4 % of population), those experiencing MSHH were significantly more likely to cease EBF between 4 and 6 months (aHR 2.38, 95 % CI 1.02–5.58). The prevalence of HHFI, maternal malnutrition, and suboptimal infant feeding practices are high and the causal relationships among these phenomena must be further explored. 相似文献
117.
Michele Farisco Enrico Alleva Flavia Chiarotti Simone Macri Carlo Petrini 《Neuroethics》2014,7(1):93-104
Notwithstanding fundamental methodological advancements, scientific information about disorders of consciousness (DOCs)—e.g. Vegetative State/Unresponsive Wakefulness Syndrome (VS/UWS) and Minimally Conscious State (MCS)—is incomplete. The possibility to discriminate between different levels of consciousness in DOC states entails treatment strategies and ethical concerns. Here we attempted to investigate Italian clinicians’ and basic scientists’ opinions regarding some issues emerging from the care and the research on patients with DOCs. From our survey emerged that Italian physicians working with patients with DOCs give a central role to ethics. Current Italian regulation regarding basic research conducted in patients with DOCs apparently risks to be inadequate to support scientific advancement, and would deserve a different assessment compared to ordinary treatments. We think the results of our survey deserve attention from an international audience because they exemplify the difficulty to define a shared approach to the issues related to patients with DOCs and the necessity to better assess both the ordinary and experimental treatment of patients with DOCs at the ethical and legal level. 相似文献
118.
Sergio Sabbatani Fausto Catena Flavia Neri Carlo Vallicelli Luca Ansaloni Massimo Sartelli Federico Coccolini Salomone Di Saverio Rodolfo Catena Daniel Lazzareschi Antonio Tarasconi Hariscine K. Abongwa Belinda De Simone Antonio Pinna 《The Journal of surgical research》2014
Background
The first reliable statistic data about perioperatory mortality were published in 1841 by the French Joseph-Francois Malgaigne (1806–1863): he referred to a mean mortality of 60% for amputations and this bad result was to be attributed mainly to hospital acquired diseases. The idea of “hospital acquired disease” although vague, included five infective nosologic entities, which at that time were diagnosed more frequently: erysipelas, tetan, pyemia, septicemia, and gangrene. Nonetheless, the suppuration with pus production was considered from most of the surgeons and doctors of that time as a necessary and unavoidable step in the process of wound healing. During the end of the eighteenth century, hospitals of the main European cities were transforming into aggregations of several wards, where the high concentration of patients created poor sanitary conditions and a consistent increase of perioperatory mortality. In 1865, Lister applied his first antiseptic dressing on the surface of an exposed fracture. These experimental attempts lead to an effective reduction of wound infections respect to the dressing with strings used previously.Discussion
Lister's innovations in the field of wound treatment were based on two brand new concepts: germs causing rot were ubiquitarious and the wound infection was not a normal step in the process of wound healing. The concept of antisepsis was hardly accepted in the European surgical world: “Of all countries, Italy is the most indifferent and uninterested in experimenting this method, which has been so favorably judged from the greatest surgical societies in Germany”. This quotation from the young surgeon Giuseppe Ruggi (1844–1925) from Bologna comes from his article where he presented his first experiences on aseptic medications started the previous year in the Surgical Department of Maggiore Hospital in Bologna. In his report, Ruggi described the adopted technique and suggested that the medication should be extended to all the surgical patients of the hospital:“… this is needed to totally remove from the hospital all those elements of infection which grow in the wounds dressed with the old method”. The experimentation of this new dressing for the few treated cases was rigorous and concerned both the sterilization of surgical tools with the fenic acid (5%) and the shaving of the skin. Ruggi also observed that there was no correlation between the seriousness of the wound and its extension or way of healing: when “simple” cases that “should heal without complication” showed fever he often realized that “it was often due to a medication performed without following the rules for an accurate disinfection and dressing”. Ruggi thought that the fever was connected to “reabsorption of pyrogenic substances, which can be removed cleaning and disinfecting the wound” in cases of wounds not accurately dressed and rarely medicated. Frequent postoperative medications of the wound were able to eliminate the fever within 2 h. Ruggi's attitude toward the fine reasoning lead him to introduce the concept of immunodeficiency related to physical deterioration: “… patients treated for surgical disease may sometimes suffer from complications of medical conditions, which initially escape the most accurate investigations… The surgical operation could, in some cases, hold the balance of power”.Conclusions
The obtained results, published in 1879, appear extremely interesting. As he wrote in 1898, for the presentation of his case record of more than 1000 laparotomies, he had started “… operating as a young surgeon without any tutor, helped only by his mind and what he could deduce from publications existing at the moment …”. 相似文献119.
Gabriele Sani Georgios D. Kotzalidis Isabella Panaccione Alessio Simonetti Lavinia De Chiara Antonio Del Casale Elisa Ambrosi Flavia Napoletano Delfina Janiri Emanuela Danese Nicoletta Girardi Chiara Rapinesi Daniele Serata Giovanni Manfredi Alexia E. Koukopoulos Gloria Angeletti Ferdinando Nicoletti Paolo Girardi 《Psychiatry investigation》2014,11(1):95-101
The treatment of premenstrual dysphoric disorder (PMDD) is far from satisfactory, as there is a high proportion of patients who do not respond to conventional treatment. The antidiuretic sulfonamide, acetazolamide, inhibits carbonic anhydrase and potentiates GABAergic transmission; the latter is putatively involved in PMDD. We therefore tried acetazolamide in a series of women with intractable PMDD. Here, we describe a series of eight women diagnosed with DSM-IV-TR PMDD, five of whom had comorbidity with a mood disorder and one with an anxiety disorder, who were resistant to treatment and responded with symptom disappearance after being added-on 125 mg/day acetazolamide for 7-10 days prior to menses each month. Patients were free from premenstrual symptoms at the 12-month follow-up. We suggest that acetazolamide may be used to improve symptoms of PMDD in cases not responding to other treatments. GABAergic mechanisms may be involved in counteracting PMDD symptoms. 相似文献
120.
Allan K.N. Alencar Sharlene L. Pereira Flavia E. da Silva Luiza V.P. Mendes Valéria do M.N. Cunha Lidia M. Lima Tadeu L. Montagnoli Celso Caruso-Neves Emanuelle B. Ferraz Roberta Tesch José H.M. Nascimento Carlos M.R. Sant'Anna Carlos A.M. Fraga Eliezer J. Barreiro Roberto T. Sudo Gisele Zapata-Sudo 《International journal of cardiology》2014