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51.
Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.  相似文献   
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BACKGROUND: Corticosteroids have been recommended to facilitate rapid recovery after cardiac surgery. We previously reported that dexamethasone given after induction of anesthesia decreases the incidence of postoperative shivering. We performed a post hoc analysis of the data obtained during that study, focusing on secondary outcomes. METHODS: A total of 235 adult patients undergoing elective coronary or valvular heart surgery were randomized to receive dexamethasone 0.6 mg/kg or placebo after induction of anesthesia. Patients who had pharmacologically treated diabetes mellitus, had hypersensitivity to dexamethasone, or were receiving treatment with corticosteroids were excluded. RESULTS: We found that, compared with placebo, patients receiving dexamethasone were more likely to remain tracheally intubated for 6 hours or less (26.4% vs 10.0%, p = 0.020) and had a lower incidence of early postoperative fever (20.2% vs 36.8%, p = 0.009) and new-onset atrial fibrillation during the first 3 days postoperatively (18.9% vs 32.3%, p = 0.027). However, we could not demonstrate a statistical difference in the intensive care unit or hospital length of stay, or in overall morbidity and mortality. The dexamethasone-treated patients were also more likely to have a higher blood glucose on admission to the intensive care unit (186 mg/dL vs 143 mg/dL, p = 0.012). CONCLUSIONS: Dexamethasone facilitates early tracheal extubation and is associated with a lower incidence of early postoperative fever and new-onset atrial fibrillation. Apart from a treatable decreased glucose tolerance, dexamethasone treatment was not shown to affect morbidity or mortality significantly.  相似文献   
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Background:In latest decades, mortality rates from ischemic heart disease (IHD) had declined steadily in most of the world as a consequence of improvements in prevention and therapy.Objective:The aim of this study was to analyze trends in mortality caused by IHD in the region of the Americas from 2000 to 2019.Methods:Estimates of the age-adjusted mortality rate (AAMR) due to IHD were extracted from the Data Portal on Noncommunicable Diseases, Mental Health, and External Causes (ENLACE), Pan American Health Organization. We used Joinpoint regression to analyze significant changes in mortality trends by country, gender, geographical sub-region, and country income, according to the World Bank classification. We also calculated the average annual percent change (AAPC) mortality rate for the overall period in the Americas as a whole and by country and sub-region.Results:In the region of the Americas, the AAMR from IHD decreased from 117.80 (95% uncertainty interval (UI)) 106.64–135.90) in 2000 to 73.64 (62.65–92.66) per 100,000 in 2019. In males, from 149.08 (95% UI 138.23–168.08) to 96.02 (95% UI 83.48–117.19) and in females 92.36 (95% UI 81.35–109.42) to 54.84 (95% UI 45.28–71.76). The AAPC mortality rate in the region decreased –2.5% (95% CI: –2.7, –2.3), with joinpoints in 2007 and 2012, –2.3% (95% CI: –2.5, –2.1) in men and –2.7% (95% CI: –3.0, –2.5) in women. According to the sub-region analysis, the highest decrease was recorded in North America, AAPC –3.1% (95% CI: –3.3, –3.0) with one joinpoint in 2011, whereas there was a stagnation of the mortality rate in Central America, Mexico, and Latin Caribbean with an AAPC of 0.1 (–0.2, 0.3) with one joinpoint in 2007.Conclusions:Age-adjusted mortality rate from IHD between 2000 and 2019 has decreased in the region of the Americas. However, different trends were observed, North America had the highest reduction in AAPC, while Central America, Mexico, and Latin Caribbean Region had a stagnation. This trend was highly influenced by country income.  相似文献   
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ObjectiveManagement of postoperative pain after head and neck cancer surgery is a complex issue, requiring a careful balance of analgesic properties and side effects. The objective of this review is to discuss the efficacy and safety of multimodal analgesia (MMA) for these patients.MethodsPubmed, Cochrane, Embase, Scopus, and clinicaltrials.gov were systematically searched for all comparative studies of patients receiving MMA (nonsteroidal anti‐inflammatory drugs (NSAIDs), acetaminophen, anticonvulsants, local anesthetics, and corticosteroids) for head and neck cancer surgeries. The primary outcome was additional postoperative opioid usage, and secondary outcomes included subjective pain scores, complications, adverse effects, and 30‐day outcomes.ResultsA total of five studies representing 592 patients (MMA, n = 275; non‐MMA, n = 317) met inclusion criteria. The most commonly used agents were gabapentin, NSAIDs, and acetaminophen (n = 221), NSAIDs (n = 221), followed by corticosteroids (n = 35), dextromethorphan (n = 40), and local nerve block (n = 19). Four studies described a significant decrease in overall postoperative narcotic usage with two studies reporting a significant decrease in hospital time. Subjective pain scores widely varied with two studies reporting reduced pain at postoperative day 3. There were no differences in surgical outcomes, medical complications, adverse effects, or 30‐day mortality and readmission rates.ConclusionMMA is an increasingly popular strategy that may reduce dependence on opioids for the treatment of postoperative pain. A variety of regimens and protocols are available for providers to utilize in the appropriate head and neck cancer patient.  相似文献   
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Background: Craniovertebral junction (CVJ) schwannomas are rare, with surgery and stereotactic radiosurgery (SRS) being effective yet challenging options. We systematically reviewed the literature on CVJ schwannomas. Methods: PubMed, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA statement to include studies reporting CVJ schwannomas. Clinical features, management, and outcomes were analyzed. Results: We collected 353 patients from 101 included articles. Presenting symptoms were mostly neck pain (30.3%) and headache (26.3%), with most cranial neuropathies involving the XII (31.2%) and X (24.4%) nerves. Most tumors originated from C2 (30.9%) and XII (29.4%) nerves, being extracranial (45.1%) and intradural-extradural (44.2%). Erosion of C1–C2 vertebrae (37.1%), the hypoglossal canal (28.3%), and/or jugular foramen (20.1%) were noted. All tumors were operated, preferably with the retrosigmoid approach (36.5%), with the far-lateral approach (29.7%) or with the posterior approach and cervical laminectomy (26.9%), far-lateral approaches (14.2%), or suboccipital craniotomy with concurrent cervical laminectomy (14.2%). Complete tumor resection was obtained most frequently (61.5%). Adjuvant post-surgery stereotactic radiosurgery was delivered in 5.9% patients. Median follow-up was 27 months (range, 12–252). Symptom improvement was noted in 88.1% of cases, and cranial neuropathies showed improvement in 10.2%. Post-surgical complications occurred in 83 patients (23.5%), mostly dysphagia (7.4%), new cranial neuropathies (6.2%), and cerebrospinal fluid leak (5.9%). A total of 16 patients (4.5%) had tumor recurrence and 7 died (2%), with median overall survival of 2.7 months (range, 0.1–252). Conclusions: Microsurgical resection is safe and effective for CVJ schwannomas. Data on SRS efficacy and indications are still lacking, and its role deserves further evaluation.  相似文献   
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BackgroundAnthracycline use in metastatic breast cancer (MBC) is hindered by cumulative exposure limits and risk of cardiotoxicity. Pixantrone, a novel aza-anthracenedione with structural similarities to mitoxantrone and anthracyclines, is theorized to exhibit less cardiotoxicity, mainly due to lack of iron binding. We conducted a randomized phase II study to evaluate the efficacy and safety of 2 dosing schedules of pixantrone in patients with refractory HER2-negative MBC.MethodsIntravenous pixantrone was administered at 180 mg/m2 every 3 weeks (group A) versus 85 mg/m2 on days 1, 8, and 15 of a 28-day cycle (group B). Primary endpoint was objective response rate (ORR) and secondary endpoints included progression-free survival (PFS), median 6-month PFS, overall survival (OS), safety, quality of life, and serial assessment of circulating tumor cells. A 20% ORR was targeted as sufficient for further testing of pixantrone in this patient population.ResultsForty-five patients were evaluable, with 2 confirmed partial responses in group A and 1 in group B. The trial was terminated due to insufficient activity. Overall median PFS and OS were 2.8 (95% confidence interval [CI]: 2.0-4.1) and 16.8 (95% CI: 8.9-21.6) months, respectively. Notable overall grade 3-4 adverse events were the following: neutrophil count decrease (62%), fatigue (16%), and decrease in ejection fraction (EF) (4%).ConclusionPixantrone has insufficient activity in the second- and third-line MBC setting. It appears, however, to have limited cardiotoxicity. (ClinicalTrials.gov ID: NCT01086605).  相似文献   
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