183 research outputs found

    Qualità Ossea e Osteoporosi: un nuovo metodo di valutazione antropologica su reperti scheletrici umani recenti ed antichi

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    Osteoporosis is a major health problem in the world; it is an insidious disease that, silently, reduces bone mass making the bones weak and more prone to fractures. The attention that is paid is very great, especially in industrialized countries where the life expectancy is high and in which osteoporosis is becoming a disease with high social impact. In paleopathology, many studies have focused on bone loss in past populations. The aim of these works is to define the traces of a disease that is only apparently modern. The current study investigates a new methodological approach to assess bone health in recent and ancient human skeletal remains. The use of the Quantitative Ultrasonometry (QUS), applied for the first time on skeletal samples, has allowed to evaluate bone tissue identifying characteristics not only related to its mass and density, but also to the structure and to its elastic component. Starting to the differences found between sexes and age, ultrasonometric standard were created to provide a reference point for archaeological and to help identify osteoporosis or simple bone loss cases. The application of this method on a medieval sample has allowed to validate it on an archaeological sample demonstrating its efficacy

    Quantitative ultrasonometry for the diagnosis of osteoporosis in human skeletal remains: New methods and standards

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    Abstract Osteoporosis, a complex and heterogeneous disorder with a multi-factorial etiology, is characterized by abnormal bone loss leading to an increased risk of fractures. In recent years, the study of osteoporosis and bone mineral quality has received increasing interest by biological anthropologists. In particular, the study of bone quality in ancient populations in relation to sex, age and cultural background can provide important insights into the diachronic evolution of a seemingly modern pathology. However, a number of challenges remain in the determination of bone loss in ancient remains, partly due to the methodological approaches applied in the anthropological analysis. This underlines the need for a new methodology and new standards, specifically created and adapted to human skeletal remains. The current study aims to develop a new methodology to assess bone quality in modern and ancient human skeletal remains using Quantitative Ultrasonometry, applied for the first time to a skeletal sample of known age-at-death and sex (Frassetto collection, University of Bologna). After the assessment of intra- and inter-observer reliability, new ultrasonometric standards based on the analysis of age-related and sex-related changes in bone quantity and quality were created, providing a reference point for the analysis of osteoporosis and bone loss in skeletal remains. The applicability of the method was tested in a medieval sample including both males and females. The low intra- and inter-observer errors suggest that the Phalangeal Ultrasonometry is a reliable and valid technique that can be applied to modern and ancient human skeletons

    Experimental left pneumonectomy in pigs. Procedure and management

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    Background Because there is no detailed description of procedures and perioperative management of major pulmonary resections in swine, we reviewed our experience to delineate the most effective practice in performing left pneumonectomy. Materials and methods Analysis of 11 consecutive left pneumonectomies. Animal data, operative reports, anesthesia records, and perioperative facts were evaluated. Follow-up information until postoperative day 60, methods of care-taking, therapy administration, and all the stabling aspects were systematically assessed. The investigation was aimed at highlighting those procedural steps or details which make the difference in optimizing the available resources (animals, instruments, and personnel). No statistical analysis was performed considering data characteristics and the descriptive nature of information. Results Surgery requires a median time of 2 h and 16 min; two operators and one anesthesiologist represent the basic team. Circulators' number depends on goals to accomplish. The most straightforward procedure requires careful dissection of the pulmonary ligament (limited view), pulmonary veins (low variability), pulmonary artery (delicate), and finally bronchus (no variability observed). The key factors for good anesthesia management have been identified: sedation by caregivers, preoxygenation before induction of general anesthesia, high respiratory rates with low tidal volume after pneumonectomy, and noninvasive ventilation after extubation. Antibiotic prophylaxis has been performed. Postoperative care must be continuous until animals are able to stand up, afterward "preventive noncurative," and always animal friendly. Ideas for minimally stressful therapy administration are helpful. Conclusions After the delineation of this methodology, the compliance to a routine practice allowed us to reduce time, stress, and cost; quality and quantity of possible research increased

    Too much tolerance for hyperoxemia in mechanically ventilated patients with SARS-CoV-2 pneumonia? Report from an Italian intensive care unit

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    Background: In COVID-19 patients requiring mechanical ventilation, the administration of high oxygen (O2) doses for prolonged time periods may be necessary. Although life-saving in most cases, O2 may exert deleterious effects if administered in excessive concentrations. We aimed to describe the prevalence of hyperoxemia and excessive O2 administration in mechanically ventilated patients with SARS-CoV-2 pneumonia and determine whether hyperoxemia is associated with mortality in the Intensive Care Unit (ICU) or the onset of ventilator-associated pneumonia (VAP). Materials and methods: Retrospective single-center study on adult patients with SARS-CoV-2 pneumonia requiring invasive mechanical ventilation for ≥48 h. Patients undergoing extracorporeal respiratory support were excluded. We calculated the excess O2 administered based on the ideal arterial O2 tension (PaO2) target of 55–80 mmHg. We defined hyperoxemia as PaO2 > 100 mmHg and hyperoxia + hyperoxemia as an inspired O2 fraction (FiO2) > 60% + PaO2 > 100 mmHg. Risk factors for ICU-mortality and VAP were assessed through multivariate analyses. Results: One hundred thirty-four patients were included. For each day of mechanical ventilation, each patient received a median excess O2 of 1,121 [829–1,449] L. Hyperoxemia was found in 38 [27–55]% of arterial blood gases, hyperoxia + hyperoxemia in 11 [5–18]% of cases. The FiO2 was not reduced in 69 [62–76]% of cases of hyperoxemia. Adjustments were made more frequently with higher PaO2 or initial FiO2 levels. ICU-mortality was 32%. VAP was diagnosed in 48.5% of patients. Hyperoxemia (OR 1.300 95% CI [1.097–1.542]), time of exposure to hyperoxemia (OR 2.758 [1.406–5.411]), hyperoxia + hyperoxemia (OR 1.144 [1.008–1.298]), and daily excess O2 (OR 1.003 [1.001–1.005]) were associated with higher risk for ICU-mortality, independently of age, Sequential Organ failure Assessment score at ICU-admission and mean PaO2/FiO2. Hyperoxemia (OR 1.033 [1.006–1.061]), time of exposure to hyperoxemia (OR 1.108 [1.018–1.206]), hyperoxia + hyperoxemia (OR 1.038 [1.003–1.075]), and daily excess O2 (OR 1.001 [1.000–1.001]) were identified as risk factors for VAP, independently of body mass index, blood transfusions, days of neuromuscular blocking agents (before VAP), prolonged prone positioning and mean PaO2/FiO2 before VAP. Conclusion: Excess O2 administration and hyperoxemia were common in mechanically ventilated patients with SARS-CoV-2 pneumonia. The exposure to hyperoxemia may be associated with ICU-mortality and greater risk for VAP

    Near-infrared spectroscopy for assessing tissue oxygenation and microvascular reactivity in critically ill patients: a prospective observational study

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    Impaired microcirculatory perfusion and tissue oxygenation during critical illness are associated with adverse outcome. The aim of this study was to detect alterations in tissue oxygenation or microvascular reactivity and their ability to predict outcome in critically ill patients using thenar near-infrared spectroscopy (NIRS) with a vascular occlusion test (VOT)

    Long-term complete response in a patient with liver metastases from breast cancer treated with metronomic chemotherapy

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    Background. Preclinical studies have shown that several chemotherapeutic agents at low doses may affect the vascular system. Here we report the case of a patient with long-term cancer control by metronomic chemotherapy. Case presentation. A 62-year-old woman with breast cancer underwent a left mastectomy in July 2007. For a liver metastasis she was given first-line chemotherapy with doxorubicin plus paclitaxel every 21 days. A CT scan after the sixth cycle showed a partial response. It was decided to stop the treatment with doxorubicin and paclitaxel, and start metronomic therapy with cyclophosphamide 50 mg daily orally and methotrexate 2.5 mg twice daily, 2 days a week. After 6 months of this maintenance treatment, CT scan showed a complete response. We examined the expression of vascular endothelial growth factor receptor 2 (VEGFR2) in histological sections of the primary tumor of our patient, finding evidence of overexpression of the receptor. The metronomic treatment is still ongoing, and after 60 months the patient maintains a complete response. Conclusion. This clinical case highlights how suitable metronomic chemotherapy can be used as maintenance therapy, allowing long-term treatment with no significant toxicity. This case suggests that the level of VEGFR2 is predictive of best response to antiangiogenic therapy

    Effects of short-term hyperoxia on erythropoietin levels and microcirculation in critically Ill patients: a prospective observational pilot study

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    BACKGROUND: The normobaric oxygen paradox states that a short exposure to normobaric hyperoxia followed by rapid return to normoxia creates a condition of 'relative hypoxia' which stimulates erythropoietin (EPO) production. Alterations in glutathione and reactive oxygen species (ROS) may be involved in this process. We tested the effects of short-term hyperoxia on EPO levels and the microcirculation in critically ill patients.METHODS: In this prospective, observational study, 20 hemodynamically stable, mechanically ventilated patients with inspired oxygen concentration (FiO2) \ue2\u89\ua40.5 and PaO2/FiO2\ue2\u80\u89\ue2\u89\ua5\ue2\u80\u89200\uc2\ua0mmHg underwent a 2-hour exposure to hyperoxia (FiO2 1.0). A further 20 patients acted as controls. Serum EPO was measured at baseline, 24\uc2\ua0h and 48\uc2\ua0h. Serum glutathione (antioxidant) and ROS levels were assessed at baseline (t0), after 2\uc2\ua0h of hyperoxia (t1) and 2\uc2\ua0h after returning to their baseline FiO2 (t2). The microvascular response to hyperoxia was assessed using sublingual sidestream dark field videomicroscopy and thenar near-infrared spectroscopy with a vascular occlusion test.RESULTS: EPO increased within 48\uc2\ua0h in patients exposed to hyperoxia from 16.1 [7.4-20.2] to 22.9 [14.1-37.2] IU/L (p\ue2\u80\u89=\ue2\u80\u890.022). Serum ROS transiently increased at t1, and glutathione increased at t2. Early reductions in microvascular density and perfusion were seen during hyperoxia (perfused small vessel density: 85% [95% confidence interval 79-90] of baseline). The response after 2\uc2\ua0h of hyperoxia exposure was heterogeneous. Microvascular perfusion/density normalized upon returning to baseline FiO2.CONCLUSIONS: A two-hour exposure to hyperoxia in critically ill patients was associated with a slight increase in EPO levels within 48\uc2\ua0h. Adequately controlled studies are needed to confirm the effect of short-term hyperoxia on erythropoiesis.TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.gov ), NCT02481843 , registered 15th June 2015, retrospectively registered

    COVID-19 Rapid Antigen Test Screening in Patients on Hemodialysis

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    Introduction. Patients receiving in-center hemodialysis are extremely vulnerable to COVID-19. It is unclear if routine screening of asymptomatic hemodialysis patients is an effective strategy to prevent COVID-19 outbreaks within the dialysis unit. Methods. We conducted a retrospective analysis of in-center hemodialysis patients who underwent bimonthly COVID-19 rapid antigen test screening from February 15(th) to December 26(th), 2021. Nasal rapid antigen testing was performed in all asymptomatic patients. All rapid antigen-positive tests were confirmed by RT-PCR nasopharyngeal swab. Besides universal rapid antigen screening, RT-PCR testing was conducted in all symptomatic patients and contacts of COVID-19 subjects. Results. Overall, 4079 rapid antigen tests were performed in 277 hemodialysis patients on chronic hemodialysis with a mean age of 68.4 +/- 14.6 years. Thirty-eight (0.9%) rapid antigen tests resulted positive. Only five (13.8%) positive-rapid antigen tests were also positive by RT-PCR testing. During the same period, 219 patients regularly screened by rapid antigen tests bimonthly underwent 442 RT-PCR nasopharyngeal swabs for clinical reasons. RT-PCR testing yielded a positive result in 13 (5.9%) patients. The time elapsed between PCR and the negative-rapid antigen test was 7.7 +/- 4.6 days (range 1.8-13.9 days). At the end of the follow-up, 6.4% of the population on in-center hemodialysis contracted COVID-19, and routine rapid antigen tests detected only 5 out of 18 (27.7%) COVID-19 cases. No outbreaks of COVID-19 were identified within the dialysis unit. Conclusion. Bimonthly rapid antigen screening led to the early diagnosis of COVID-19 in less than one-third of cases. The short incubation period of the new SARS-CoV-2 variants makes bimonthly test screening inadequate for an early diagnosis of COVID-19. More frequent tests are probably necessary to improve the utility of COVID-19 nasal rapid antigen test in patients on hemodialysis
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