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101.

Introduction:

In patients with severe aortic stenosis, low-gradient, low-flow and preserved ejection fraction (≥ 50%) (LG/LFp) the decrease in stroke volume index (Svi) could be due to diminished contractility. The aim of this study was to analyze if low Svi in patients with LG/LFp is related to a decrease in contractility.

Methods:

Thirty patients with LF/LGp and 63 normal subjects were studied with Doppler echocardiography. The level of contractility (LC) was assessed by mean of midwall shortening fraction (mSF) – end-systolic stress (ESS) relationship. Relative wall thickness (RWT) and aortic valve area (AVA) were calculated.

Results:

LC was diminished in 40% of LF/LGp patients. By bivariate analysis LC correlated with RWT and mSF. Svi correlated with AVA but not with LC. In multiple linear regression RWT and mSF were predictors independents of LC. About Svi, AVA was the only predictor independent variable.

Conclusion:

Decreased contractility was present in 40% of LF/LGp patients despite preserved ejection fraction. LC had correlation with mSF and EPR. Low Svi appears to be related to aortic stenosis severity rather than low contractility.Key words: Aortic stenosis, Contractility, Echocardiography, Ventricular function  相似文献   
102.
Recurrent respiratory papillomatosis can be a devastating condition for a child, with severe consequences. Currently, there is no proven successful medical treatment. We describe the use of systemic bevacizumab to treat two children affected by aggressive recurrent respiratory papillomatosis. Respiratory symptoms and quality of life improved dramatically in both patients, without observing any toxicity. The only complication was mild proteinuria. Systemic bevacizumab is a promising adjuvant treatment in aggressive recurrent respiratory papillomatosis in children. It is effective and well tolerated. Further studies are needed to establish the optimal dosing frequency and duration of therapy. Laryngoscope, 129:1001–1004, 2019  相似文献   
103.
Computed tomography (CT) and conventional radiography of the sacroiliac joint were compared in 43 patients. CT appeared to be far more sensitive and equally specific in the recognition of sacroiliitis. In a number of patients with sacroiliitis diagnosed by both techniques, CT demonstrated abnormalities that were not demonstrated by conventional radiographs. Of those patients with clinical evidence of sacroiliitis and HLA—B27 positivity, 50% had negative or equivocal radiographs compared to 19% who had negative computed tomographic images for sacroiliiti.  相似文献   
104.
ObjectiveTo compare the predictive value of the quick COVID-19 Severity Index (qCSI) and the National Early Warning Score (NEWS) for 90-day mortality amongst COVID-19 patients.MethodsMulticenter retrospective cohort study conducted in adult patients transferred by ambulance to an emergency department (ED) with suspected COVID-19 infection subsequently confirmed by a SARS-CoV-2 test (polymerase chain reaction). We collected epidemiological data, clinical covariates (respiratory rate, oxygen saturation, systolic blood pressure, heart rate, temperature, level of consciousness and use of supplemental oxygen) and hospital variables. The primary outcome was cumulative all-cause mortality during a 90-day follow-up, with mortality assessment monitoring time points at 1, 2, 7, 14, 30 and 90 days from ED attendance. Comparison of performances for 90-day mortality between both scores was carried out by univariate analysis.ResultsFrom March to November 2020, we included 2,961 SARS-CoV-2 positive patients (median age 79 years, IQR 66–88), with 49.2% females. The qCSI score provided an AUC ranging from 0.769 (1-day mortality) to 0.749 (90-day mortality), whereas AUCs for NEWS ranging from 0.825 for 1-day mortality to 0.777 for 90-day mortality. At all-time points studied, differences between both scores were statistically significant (p < .001).ConclusionPatients with SARS-CoV-2 can rapidly develop bilateral pneumonias with multiorgan disease; in these cases, in which an evacuation by the EMS is required, reliable scores for an early identification of patients with risk of clinical deterioration are critical. The NEWS score provides not only better prognostic results than those offered by qCSI at all the analyzed time points, but it is also better suited for COVID-19 patients.

KEY MESSAGES

  • This work aims to determine whether NEWS is the best score for mortality risk assessment in patients with COVID-19.
  • AUCs for NEWS ranged from 0.825 for 1-day mortality to 0.777 for 90-day mortality and were significantly higher than those for qCSI in these same outcomes.
  • NEWS provides a better prognostic capacity than the qCSI score and allows for long-term (90 days) mortality risk assessment of COVID-19 patients.
  相似文献   
105.
A subcutaneous air pouch formed in Sprague-Dawley rats was used to study the effect of diets enriched in γ-linolenic acid (GLA) (in plant seed oil) and eicosapentaenoic acid (EPA) (in fish oil) on acute inflammation induced by monosodium urate crystals. The GLA-enriched diet suppressed significantly the cellular phase of inflammation (polymorphonuclear leukocyte accumulation, crystal phagocytosis, and lysosomal enzyme activity), but it had little effect on the fluid phase (exudate volume and protein concentration). In contrast, the EPA-enriched diet suppressed the fluid phase but not the cellular phase of inflammation. The findings indicate that the fluid and cellular phases of acute inflammation can be controlled independently. A combined diet of fish oil and plant seed oil (EPA-enriched and GLA-enriched) reduced both the cellular and fluid phases of inflammation. Thus, dietary provision of alternative substrates for oxidative metabolism (other than arachidonic acid) modifies monosodium urate crystal-induced acute inflammation.  相似文献   
106.
This is a short communication based on recent high-impact publications related to how various chemical materials and substrate modifications could be tuned for nano- and microdevices, where their application for high point-of-care bioanalysis and further applications in life science is discussed. Hence, they have allowed different high-impact research topics in a variety of fields, from the control of nanoscale to functional microarchitectures embedded in various support materials to obtain a device for a given application or use. Thus, their incorporation in standard instrumentation is shown, as well as in new optical setups to record different classical and non-classical light, signaling, and energy modes at a variety of wavelengths and energy levels. Moreover, the development of miniaturized instrumentation was also contemplated. In order to develop these different levels of technology, the chemistry, physics and engineering of materials were discussed. In this manner, a number of subjects that allowed the design and manufacture of devices could be found. The following could be mentioned by way of example: (i) nanophotonics; (ii) design, synthesis and tuning of advanced nanomaterials; (iii) classical and non-classical light generation within the near field; (iv) microfluidics and nanofluidics; (v) signal waveguiding; (vi) quantum-, nano- and microcircuits; (vii) materials for nano- and microplatforms, and support substrates and their respective modifications for targeted functionalities. Moreover, nano-optics in in-flow devices and chips for biosensing were discussed, and perspectives on biosensing and single molecule detection (SMD) applications. In this perspective, new insights about precision nanomedicine based on genomics and drug delivery systems were obtained, incorporating new advanced diagnosis methods based on lab-on-particles, labs-on-a-chip, gene therapies, implantable devices, portable miniaturized instrumentation, single molecule detection for biophotonics, and neurophotonics. In this manner, this communication intends to highlight recent reports and developments of nano- and microdevices and further approaches towards the incorporation of developments in nanophotonics and biophotonics in the design of new materials based on different strategies and enhanced techniques and methods. Recent proofs of concept are discussed that could allow new substrates for device manufacturing. Thus, physical phenomena and materials chemistry with accurate control within the nanoscale were introduced into the discussion. In this manner, new potential sources of ideas and strategies for the next generation of technology in many research and development fields are showcased.

This is a short communication based on recent high-impact publications related to how various chemical materials and substrate modifications could be tuned for nano- and microdevices, where their application for high point-of-care bioanalysis and further applications in life science is discussed.  相似文献   
107.
Background: We evaluated the impact of surgically-induced weight loss on Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS), electrocardiographic changes, pulmonary arterial pressure and daytime sleepiness in morbidly obese patients. Methods: 16 women and 13 men (n=29) underwent bariatric surgery in a 3-year period. The following tests were performed before and 1 year after surgery: nocturnal polysomnography, daytime Multiple Sleep Latency Test (MSLT), and echocardiogram. Results: Mean age was 37.9±11 years (range 20-56). Preoperative body mass index was 56.5±12.3 kg/m2 and it was 39.2±8.5 kg/m2 at 13.7±6.6 months follow-up. Performed surgical procedures included: vertical banded gastroplasty in 6, Roux-en-Y gastric bypass in 12, and Distal Roux-en-Y gastric bypass in 11. Weight loss induced by surgery eliminated OSAHS in 46% of obese patients with an important improvement in oxygen saturation. Neck, thorax, waist and hip circumferences decreased significantly after surgical intervention but only neck circumference correlated significantly with the apnea/hypopnea index (Spearman rho=0.63, P <0.0001). Electrocardiographic abnormalities were present in 9 patients (31%) before surgery (sinus arrhythmia, ventricular arrhythmias, and sinus arrest). The number of electrocardiographic abnormalities decreased after surgery but new abnormalities appeared in some patients. Systolic pulmonary arterial pressure significantly decreased in the group of patients in whom OSAHS disappeared after surgery. Daytime sleepiness persisted after surgery in most patients. Conclusion: Bariatric surgery effectively reduces respiratory disturbances during sleep and improves pulmonary hypertension. Electro cardiographic abnormalities change after surgery. Daytime sleepiness appeared not to be related to respiratory disturbances during sleep.  相似文献   
108.
Infectious complications are a major cause of morbidity and mortality in patients who undergo autologous stem cell transplantation (ASCT). We examined 476 patients with hematologic malignancies (401) or solid tumors (75) who underwent ASCT between February 1990 and May 2005. Anti-infectious prophylaxis consisted of different combinations of ciprofloxacin, cotrimoxazole, fluconazole, aerosolized amphotericin B, acyclovir, and intravenous immunoglobulins. Overall, 454 patients (95%) developed fever in the first 60 days after ASCT. In the majority of patients, initial antibiotic therapy consisted of broad-spectrum beta-lactamic with or without amikacin. A glycopeptide was administered as initial therapy in 86 cases. Overall, there were 132 (29%) clinically documented infections (37 pneumonias), 79 (17%) microbiologically documented infections (65 bacteremias), and 243 (54%) fevers of unknown origin. Coagulase-negative staphylococci (18, 25%) and E coli (18, 25%) were the organisms most frequently isolated. The pattern of infection did not change throughout the study except for a significantly higher incidence of bacteremia due to gram-positive bacteria in the first 5 years of the study. Infection-related mortality was 5% (21 cases), with pneumonia the most frequent cause of death. ASCT should be considered a low-risk procedure, although new therapeutic approaches for patients developing severe respiratory infections are still needed.  相似文献   
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110.
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