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11.
ABSTRACT  Renal agenesis (RA) appears to be a multifactorial condition with combined genetic and environmental influences. We performed a retrospective case-control study of reproductive history of 26 isolated RA live births cases referred to Sicilian Registry of Congenital Malformations. A statistical significant association for birth weight if we considered all RA together and for bilateral RA alone, an increasing risk for maternal age only in the bilateral RA subgroup and a male predominance both for unilateral and bilateral RA was found. Our results show that some reproductive risk factors may be associated with RA, moreover differences found between subgroups indicate that some risk factors may be different in unilateral and bilateral RA. The association between reproductive risk factors and RA may reflect pathogenetic interaction between genetic and environmental factors. Nevertheless further studies are needed to clarify these associations and to explore the role of perinatal factors in the etiology of renal agenesis. In fact if prenatal or perinatal risk factors are in a causal chain influencing the risk for developing RA, then these data could have important implications in the prevention or treatment of this condition.  相似文献   
12.
We have previously demonstrated that N-formyl-methionyl-leucyl-phenylalanine (FMLP) induces down-regulation of FcgammaRs on human neutrophils (PMN) modifying different FcgammaR-dependent functions. The aim of this work was to assess the cellular mechanisms by which FMLP exerts this effect on FcgammaRs. The role of the microfilament and cytoskeletal apparatus in this process was evaluated using cytochalasin B (CB), an inhibitor of microfilament functions. The expression of FcgammaRIIIB and FcgammaRII after CB + FMLP treatment was drastically diminished when compared to FMLP-treated cells. Neutrophil degranulation induced by FMLP affect only 22% of the cells in response to FMLP. However, the FcgammaRs of the whole PMN population were reduced, suggesting that secretory products could be responsible for the down-regulation induced by FMLP or FMLP + CB. In fact, supernatants from FMLP-treated PMN also induced FcyRs down-regulation on naive neutrophils. Moreover, supernatants from FMLP + CB-treated PMNs exerted a higher effect. Data obtained from permeabilized PMN show that after FMLP treatment there is an intracellular depletion of both FcgammaRIIIB and FcgammaRII. In addition, the FcgammaR down-regulation is abrogated by phenyl methyl sulfonyl fluoride (PMSF) but not by other protease inhibitors such as pepstatin, thiorphan, phosphoramidon and leupeptin, suggesting a role for serine protease(s) in this process.  相似文献   
13.
Preservation of vascular endothelium integrity and functionality represents an unmet medical need. Indeed, endothelial dysfunction leads to decreased nitric oxide biosynthesis, which is prodromic of hypertension and hypercoagulability. In this panorama, the nutraceutical supplement Taurisolo®, a polyphenolic extract from Aglianico cultivar grape, rich in catechin and procyanidins, was evaluated as a vasoprotective, vasorelaxing, anti-hypertensive and anti-coagulant agent in: cell lines, isolated vessels, in vivo models of chronic hypertension and hypercoagulability, and in clinical tests of endothelial reactivity. Taurisolo® demonstrated to fully protect vascular cell viability from oxidative stimulus at 100 µg/mL and evoke vasorelaxing effects (Emax = 80.6% ± 1.9 and pEC50 = 1.19 ± 0.03) by activation of the Sirtuins-AMPK-pathway. Moreover, Taurisolo®, chronically administered at 20 mg/Kg/die in in vivo experiments, inhibited the onset of cardiac hypertrophy (heart weight/rat weight = 3.96 ± 0.09 vs. 4.30 ± 0.03), hypercoagulability (decrease of fibrinogen vs. control: p < 0.01) and hypertension (mean of Psys: 200 ± 2 vs. control 234 ± 2 mmHg) and improved endothelial function (Emax = 88.9% ± 1.5 vs. control 59.6% ± 3.6; flow-mediated dilation in healthy volunteers after 400 mg twice daily for 8 weeks vs. baseline: p = 0.019). In conclusion, Taurisolo® preserves the vascular function against ox-inflamm-ageing process and the consequent cardiovascular accidents.  相似文献   
14.
A hospital-based case-control study of renal cell cancer was conducted in northern Italy betwen 1986 and 1989, with 240 cases of renal cell cancer (150 males and 90 females), and 665 controls (445 males and 220 females) chosen on the basis of age, sex, and area of residence. No associations were found between renal cell cancer and: body mass index (BMI); number of cigarettes smoked; age at starting to smoke; years of smoking; consumption of wine, beer, spirits, coffee, decaffeinated coffee; tea; intake of animal protein, fruits, and vegetables; various resproductive factors; hormonal use; sexual habits; sexually transmitted diseases; or selected occupational exposures. The odds ratio (OR) was above unity in smokers (OR=1.34 for 15 cigarettes/day), but the trends in risk with dose or duration were not statistically significant. Significant positive associations were found between renal cell cancer and sources of fat intake, especially margarine (OR for highest vs lowest intake = 1.71), and oils (OR=1.89) whereas carrot intake showed a negative association (OR=0.62). Also, a history of nephrolithiasis and multiple episodes of cystitis showed weak positive associations (OR=2.00, 95 percent confidence interval (CI) 1.07–3.73; and OR=1.60, 95 percent CI 0.95–2.70, respectively).Address reprint requests to Dr Talamini. The work was conducted with the contribution of the Italian Association for Cancer Research, Milan, Italy and the CNR (Italian National Research Council) Applied Projects Oncology (Contract n. 85.02209.44).Drs Talamini, Barón, Barra, Bidoli, Serraino, and Franceschi are in the Epidemiology Unit, Aviano Cancer Center, Via Pedemontana Occ. 33081 Aviano (PN) Italy. At the time of this work, Dr Barón was a visiting biostatistician from the Department of Preventive Medicine and Biometrics, University of Colorado, Health Science Center, CO, funded by the National Cancer Institute (US) and the Italian National Research Council. Dr Franceschi is also chief of the Hormones and Sexual Factors and Cancer Working Group of the European Organization for Cooperation in Cancer Prevention Studies, Bruxelles, Belgium. Drs La Vecchia and Negri are in the Mario Negri Institute for Pharmacological Research, Milan, Italy. Dr La Vecchia is also in the Institute of Social and preventive Medicine, University of Lausanne, Switzerland.  相似文献   
15.
  1. 8-epi-prostaglandin (PG) F, a major F2 isoprostane, is produced in vivo by free radical-dependent peroxidation of lipid-esterified arachidonic acid. Both cyclo-oxygenase isoforms (COX-1 and COX-2) may also form free 8-epi-PGF as a minor product. It has been recently seen in human volunteers that the overall basal formation of 8-epi-PGF in vivo is mostly COX-independent and urinary 8-epi-PGF is therefore an accurate marker of ‘basal'' oxidative stress in vivo.
  2. To test the validity of this marker in the rat, we evaluated in vivo the effect of COX inhibition on the formation of 8-epi-PGF vs prostanoids. Two structurally unrelated COX inhibitors (naproxen: 30 mg kg−1 day−1; indomethacin: 4 mg kg−1 day−1) were given i.p. to rats kept in metabolic cages. In vivo formation of 8-epi-PGF was assessed by measuring its urinary excretion. Prostanoid biosynthesis was assessed by measuring urinary excretion of major metabolites of thromboxane (TX) and prostacyclin (2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF). All compounds were selectively measured by immunopurification/gas chromatography-mass spectrometry.
  3. Naproxen reduced urinary excretion of 2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF but, unexpectedly, also that of 8-epi-PGF (82, 49 and 52% inhibition, respectively). Indomethacin had a similar effect (77, 69 and 55% inhibition). Esterified 8-epi-PGF in liver and plasma remained unchanged after indomethacin.
  4. These findings prompted us to re-assess the contribution of COX activity to the systemic production of 8-epi-PGF in man. We gave naproxen (1 g day−1) to healthy subjects (four nonsmokers and four smokers). Urinary 8-epi-PGF remained unchanged in the two groups (9.63±0.99 before vs 10.24±1.01 after and 20.14±3.00 vs 19.03±2.45 ng h−1 1.73 m−2), whereas there was a marked reduction of major urinary metabolites of thromboxane and prostacyclin (about 90% for both 11-dehydro-TXB2 and 2,3-dinor-TXB2; >50% for 2,3-dinor-6-keto-PGF).
  5. To investigate whether rat COX-1 produces 8-epi-PGF more efficiently than human COX-1, we measured the ex vivo formation of 8-epi-PGF and TXB2 simultaneously in whole clotting blood. Serum levels of 8-epi-PGF and TXB2 were similar in rats and man.
  6. We conclude that a significant amount of COX-dependent 8-epi-PGF is present in rat but not in human urine under normal conditions. This implies that urinary 8-epi-PGF cannot be used as an index of near-basal oxidant stress in rats. On the other hand, our data further confirm the validity of this marker in man.
  相似文献   
16.
Purpose: To prospectively evaluate the albumin/globulin ratio (AGR), neutrophil/lymphocyte ratio (NLR), and platelet/lymphocyte ratio (PLR) diagnostic and prognostic predictive value in a stratified population of prostate cancer (PC) cases. Methods: Population was divided based on the clinical and histologic diagnosis in: Group A: benign prostatic hyperplasia (BPH) cases (494 cases); Group B: all PC cases (525 cases); Group B1: clinically significant PC (426 cases); Group B2: non-metastatic PC (416 cases); Group B3: metastatic PC (109 cases). NLR, PLR, and AGR were obtained at the time of the diagnosis, and only in cases with PC considered for radical prostatectomy, determinations were also repeated 90 days after surgery. For each ratio, cut-off values were determined by receiver operating characteristics curve (ROC) analysis and fixed at 2.5, 120.0, and 1.4, respectively, for NLR, PLR, and AGR. Results: Accuracy in predictive value for an initial diagnosis of clinically significant PC (csPC) was higher using PLR (0.718) when compared to NLR (0.220) and AGR (0.247), but, despite high sensitivity (0.849), very low specificity (0.256) was present. The risk of csPC significantly increased only according to PLR with an OR = 1.646. The percentage of cases with metastatic PC significantly increased according to high NLR and high PLR. Accuracy was 0.916 and 0.813, respectively, for NLR and PLR cut-off, with higher specificity than sensitivity. The risk of a metastatic disease increased 3.2 times for an NLR > 2.5 and 5.2 times for a PLR > 120 and at the multivariate analysis. Conclusion: PLR and NLR have a significant predictive value towards the development of metastatic disease but not in relation to variations in aggressiveness or T staging inside the non-metastatic PC. Our results suggest an unlikely introduction of these analyses into clinical practice in support of validated PC risk predictors.  相似文献   
17.
ObjectivesTo compare three-dimensional facial scans obtained by stereophotogrammetry with two different applications for smartphone supporting the TrueDepth system, a structured light technology.Materials and MethodsFacial scans of 40 different subjects were acquired with three different systems. The 3dMDtrio Stereophotogrammetry System (3dMD, Atlanta, Ga) was compared with a smartphone (iPhone Xs; Apple, Cupertino, Calif) equipped with the Bellus3D Face Application (version 1.6.11; Bellus3D Inc, Campbell, Calif) or Capture (version 1.2.5; Standard Cyborg Inc, San Francisco, Calif). Times of image acquisition and elaboration were recorded. The surface-to-surface deviation and the distance between 18 landmarks from 3dMD reference images to those acquired with Bellus3D or Capture were measured.ResultsCapturing and processing times with the smartphone applications were considerably longer than with the 3dMD system. The surface-to-surface deviation analysis between the Bellus3D and 3dMD showed an overlap percentage of 80.01% ± 5.92% and 56.62% ± 7.65% within the ranges of 1 mm and 0.5 mm discrepancy, respectively. Images from Capture showed an overlap percentage of 81.40% ± 9.59% and 56.45% ± 11.62% within the ranges of 1 mm and 0.5 mm, respectively.ConclusionsThe face image acquisition with the 3dMD device is fast and accurate, but bulky and expensive. The new smartphone applications combined with the TrueDepth sensors show promising results. They need more accuracy from the operator and more compliance from the patient because of the increased acquisition time. Their greatest advantages are related to cost and portability.  相似文献   
18.
19.

Background/purpose

Laparoscopic hepatectomies have seen a worldwide proliferation. Major anatomic resections, which were initially considered unsuitable for laparoscopy, are currently confined to a few centers of expertise. The aim of this study was to discuss the current trends and techniques in laparoscopic major hepatectomy in Europe.

Methods

The prospective databases of ten European centers were combined to provide answers to a questionnaire that had been addressed to all European teams known to perform laparoscopic liver surgery.

Results

Between 1996 and 2011 a total of 2245 laparoscopic liver resections have been carried out, of which 495 (22 %) were major resections. The proportion of laparoscopic right and left hepatectomies varied between 4 and 40 % of all major hepatectomies of the same type. Benign, primary malignant and metastatic lesions were, respectively, 22.4, 19.6 and 58 % of all indications. The different techniques and approaches, as regards hand assistance, hepatic inflow and outflow control, liver mobilization and concomitant colectomies, are discussed.

Conclusions

To date, an important level of experience of laparoscopic liver resection has been accumulated in Europe, and experience of major hepatectomies is constantly increasing. However, they remain technically very demanding procedures which should be confined to expert surgeons who have already acquired considerable experience with simpler laparoscopic liver resections.  相似文献   
20.
Dolichol (D) is a long-chain polyprenoid broadly distributed in the cell membranes, possibly endowed with a free-radical scavenging activity, whose concentration in tissues increases with increasing age. No enzyme pathway for D degradation has been discovered. In order to test the hypothesis that D might undergo a non-enzymatic free-radical mediated decomposition the effects of a xenobiotic agent (carbon tetrachloride, CCl(4)) and ultraviolet-B (UV-B) radiation on D levels were studied in liver cells isolated from male ad libitum fed Sprague-Dawley rats aged 3 or 24 months. Liver cells (90 mg/ml) were incubated in sealed flasks (6 ml cell suspension each) for 0, 5, 10 and 20 min after the addition of 25, 50 or 200 microl CCl(4) in the central well. 50 ml of a 6 mg/ml liver cell suspension were poured in a 120 cm(2) Petri dish and the sediment liver cell monolayer was exposed to UVB radiation for 0, 5, 10, 20 and 40 min. At the given time, cells were taken and D was extracted and assayed by the HPLC procedure. D levels were remarkably higher in older than in younger cells as expected ( P < 0.001). Treatment with CCl(4) and UVB caused a highly significant decrease in D ( P < 0.001) whose percentage was larger in younger than in older cells. The conclusions are that free-radicals generated either by chemical or by physical agents cause a very rapid depletion of D in liver cells, and that the effect of the free radical attack on D decomposition may be lower percentage wise in older than in younger cells, which might account at least in part for the accumulation of D in older tissues.  相似文献   
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