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41.
42.

Background

Postoperative pancreatic fistula (PPF) is the most frequent and serious complication after laparoscopic distal pancreatectomy (LDP). Our goal was to compare the performance, in terms of PPF prevention, and safety of a radiofrequency (RF)-assisted transection device versus a stapler device in a porcine LDP model.

Methods

Thirty-two animals were randomly divided into two groups to perform LDP using a RF-assisted device (RF group; n = 16) and stapler device (ST group; n = 16) and necropsied 4 weeks after surgery. The primary endpoint was the incidence of PPF. Secondary endpoints were surgery/transection time, intra/postoperative complications/deaths, postoperative plasmatic amylase and glucose concentration, peritoneal liquid amylase and interleukin 6 (IL-6) concentrations, weight variations, and histopathological changes.

Results

Two clinical and one biochemical PPF were observed in the ST and RF groups respectively. Peritoneal amylase concentration was significantly higher in the RF group 4 days after surgery, but this difference was no longer present at necropsy. Both groups presented a significant decrease in peritoneal IL-6 concentration during the postoperative follow-up, with no differences between the groups. RF group animals showed a higher postoperative weight gain. In the histopathological exam, all RF group animals showed a common pattern of central coagulative necrosis of the parenchymal surface, surrounded by a thick fibrosis, which sealed main and secondary pancreatic ducts and was not found in ST group.

Conclusions

The fibrosis caused by an RF-assisted device can be at least as safe and effective as stapler compression to achieve pancreatic parenchyma sealing in a porcine LDP model.  相似文献   
43.
The synuclein family includes three neuronal proteins, named α-synuclein, β-synuclein, and γ-synuclein, that have peculiar structural features. α-synuclein is largely known for being a key protein in the pathophysiology of Parkinson's disease (PD) and other synucleinopathies, namely, dementia with Lewy bodies and multisystem atrophy. The role of β-synuclein and γ-synuclein is less well understood in terms of physiological functions and potential contribution to human diseases. α-synuclein has been investigated extensively in both cerebrospinal fluid (CSF) and blood as a potential biomarker for synucleinopathies. Recently, great attention has been also paid to β-synuclein, whose CSF and blood levels seem to reflect synaptic damage and neurodegeneration independent of the presence of synucleinopathy. In this review, we aim to provide an overview on the pathophysiological roles of the synucleins. Because γ-synuclein has been poorly investigated in the field of synucleinopathy and its pathophysiological roles are far from being clear, we focus on the interactions between α-synuclein and β-synuclein in PD. We also discuss the role of α-synuclein and β-synuclein as potential biomarkers to improve the diagnostic characterization of synucleinopathies, thus highlighting their potential application in clinical trials for disease-modifying therapies. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society  相似文献   
44.
45.
Bacterial pathogenicity islands (PAI) often encode both effector molecules responsible for disease and secretion systems that deliver these effectors to host cells. Human enterohemorrhagic Escherichia coli (EHEC), enteropathogenic E. coli, and the mouse pathogen Citrobacter rodentium (CR) possess the locus of enterocyte effacement (LEE) PAI. We systematically mutagenized all 41 CR LEE genes and functionally characterized these mutants in vitro and in a murine infection model. We identified 33 virulence factors, including two virulence regulators and a hierarchical switch for type III secretion. In addition, 7 potential type III effectors encoded outside the LEE were identified by using a proteomics approach. These non-LEE effectors are encoded by three uncharacterized PAIs in EHEC O157, suggesting that these PAIs act cooperatively with the LEE in pathogenesis. Our findings provide significant insights into bacterial virulence mechanisms and disease.  相似文献   
46.
AIM: To evaluate whether the Helicobacter pylori status of the patient's spouse plays a role in reinfection after eradication success, and to assess the possibility of transmission of H. pylori among partners by using molecular methods. METHODS: We studied prospectively 120 patients in whom H. pylori had been eradicated. Endoscopy with biopsies and a 13C-urea breath test were performed 1 month after completing therapy. The breath test was repeated in all patients at 6 and 12 months. At the 1-year follow-up visit (or before if reinfection occurred), a breath test was also performed on the patient's partner. Samples for the molecular study included gastric biopsies from patients and gastric content obtained by the string test from partners. The heterogeneity of ureC was studied by enzymatic digestion with MseI and HhaI enzymes of a polymerase chain reaction (PCR) product of 1179 bp belonging to the ureC gene, and different band patterns were generated after electrophoresis. RESULTS: Four reinfections were diagnosed at 6 months, and four were diagnosed from 6 to 12 months (incidence 6.8% per patient-year). Seven of eight (87%) of the reinfected patients' spouses were infected, but H. pylori infection of spouses was also frequent (76%) among non-reinfected patients. In the multivariate analysis, age of the patient (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.87 to 0.99, P < 0.05), delta(13)CO(2) value after therapy (OR 2.51, 95% CI 1.14 to 5, P < 0.05), and therapy regimen (OR 6.23, 95% CI 1.25 to 31, P < 0.05) were the only variables that correlated with H. pylori recurrence. However, family variables (H. pylori status of spouse, breath test value of spouse, length of time couple had lived together, number of children living at home, household density) did not correlate with recurrences. Thus, the OR for the H. pylori status of spouse (adjusted by age, delta(13)CO(2) and therapy) was 2.93 (95% CI 0.29 to 29, P > 0.05). H. pylori recurrence occurred in seven of 92 (7.6%) patients when the spouse was infected (95% CI 3.7% to 15%), and in one of 28 (3.6%) patients when the spouse was H. pylori-negative (95% CI 0.6% to 18%) (P > 0.05; however, the power of this comparison was < 20%). Therefore, even if the spouse was infected, 92.4% of patients will remain uninfected 1 year after H. pylori eradication. Three reinfected patients (at 1 year) and their partners (also infected) agreed to have the endoscopy and string test performed, respectively. The molecular study revealed that H. pylori strains involved were different in all cases. CONCLUSION: Recurrence of H. pylori infection seems to be relatively infrequent, even if the patient's spouse is H. pylori-positive. The molecular study demonstrated that the strains in reinfected patients and their partners are different, suggesting that the patient's partner does not act as a reservoir for H. pylori reinfection.  相似文献   
47.
Acquired hemophilia is a life-threatening condition associated with a high mortality, occurring mainly in elderly patients. We report on a 92-year-old male, administered two courses of 90 microg kg(-1) of recombinant activated factor VII (rFVIIa) due to failure of human factor VIII (FVIII) therapy, without side effects nor evidence of thrombotic complications. Despite the bleeding being completely under control, the patient died on day 11 of acute respiratory failure due to pneumonia. This case confirms previous reports on the complexity and severity of this disorder, showing that rFVIIa is an effective and safe agent for achieving hemostasis even in elderly patients with a FVIII inhibitor.  相似文献   
48.
Perimortem fracture patterns in long bones, defined in previous publications, include layered breakage, bone scales, crushed margins, flakes with flake def  相似文献   
49.
To compare detectability of hyperfunctioning parathyroid tissue (HPT) by digital and analog 18F-fluorocholine PET/CT in patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT. Thirty-three patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT were prospectively included. All patients accepted to be scanned by digital and analog PET/CT in the same imaging session after a single injection of 18F-fluorocholine. Three nuclear medicine physicians evaluated the digital and analog PET/CT datasets to assess the detection rate of HPT. Maximum standard uptake values (SUVmax) of HPT and locoregional lymph nodes were measured in both systems. HPT was detected in 30/33 patients by the digital system, whereas it was detected in 22/33 patients by the analog system (p < 0.01). Moreover, in 21 of these 33 patients, both systems detected one focal 18F-fluorocholine uptake, and in one patient the digital system detected two foci. Histopathology demonstrated HPT in 32 patients and it was inconclusive in one patient. The digital PET/CT detected HPT in 29 of the 32 patients, and the analog system in 22 of the 32 (p < 0.01). All HPT suspected lesions resected and detected only by the digital system (n = 8) were < 10 mm (7.5 ± 1.3 mm), while those detected by both systems (n = 22) were > 10 mm (13 ± 3.8 mm). SUVmax of HPT lesions was significantly higher than SUVmax of locoregional lymph node independently of the PET/CT system used (4.5 ± 1.9 vs. 2.9 ± 1.3, p < 0.0001). Digital PET/CT offers superior performance over analog system in patients with suspected HPT and previous negative/inconclusive imaging examinations, particularly in sub-centimeter lesions. SUVmax can help in the differentiation between HTP and locoregional lymph nodes.  相似文献   
50.

OBJECTIVE

To analyze physical activity during adolescence in participants of the 1993 Pelotas Birth Cohort Study, Brazil.

METHODS

Data on leisure time physical activity at 11, 15, and 18 years of age were analyzed. At each visit, a cut-off point of 300 min/week was used to classify adolescents as active or inactive. A total of 3,736 participants provided data on physical activity at each of the three age points.

RESULTS

A significant decline in the proportion of active adolescents was observed from 11 to 18 years of age, particularly among girls (from 32.9% to 21.7%). The proportions of girls and boys who were active at all three age points were 28.0% and 55.1%, respectively. After adjustment for sex, economic status, and skin color, participants who were active at 11 and 15 years of age were 58.0% more likely to be active at 18 years of age compared with those who were inactive at 11 and 15 years of age.

CONCLUSIONS

Physical activity declined during adolescence and inactivity tended to track over time. Our findings reinforce the need to promote physical activity at early stages of life, because active behavior established early tends to be maintained over time.  相似文献   
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