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51.
Undifferentiated (anaplastic) thyroid carcinoma is a highly aggressive human cancer with very poor prognosis. Although there have been a few studies of candidate treatments, the fact that it is an infrequent tumor makes it very difficult to design clinical trials. A strong association has been observed between undifferentiated thyroid carcinoma and TP53 mutations in numerous molecular genetic and expression studies. Plitidepsin (Aplidin, PharmaMar, Madrid, Spain) is a novel anticancer compound obtained from a sea tunicate. This compound has been reported to induce apoptosis independently of TP53 status. We investigated the actions of plitidepsin in human thyroid cancer cells. In initial experiments using primary cultured cells from a differentiated (papillary) carcinoma, we found that 100 nmol/L plitidepsin induced apoptosis, whereas lower doses were cytostatic. Because our aim was to study the effects of plitidepsin at clinically relevant concentrations, subsequent experiments were done with a dosage regimen reflecting plasma concentrations observed in previously reported clinical trials: 100 nmol/L for 4 hours, followed by 10 nmol/L for 20 hours (4(100)/20(10) plitidepsin). This plitidepsin dosage regimen blocked the proliferation of a primary undifferentiated/anaplastic thyroid carcinoma culture obtained in our laboratory and of a commercial cell line (8305C) obtained from an undifferentiated thyroid carcinoma; however, it did not induce apoptosis. The proportion of cells in the G(1) phase of the cell cycle was greatly increased and the proportion in the S/G(2)-M phases greatly reduced, suggesting that plitidepsin blocks G(1)-to-S transition. Levels of the cyclin D1/cyclin-dependent kinase 4/p21 complex proteins were decreased and, in line with this, the levels of unphosphorylated Rb1 increased. The decrease in cell cycle proteins correlated with hypoacetylation of histone H3. Finally, we did experiments to assess how rapidly tumor cells return to their initial pretreatment proliferative behavior after 4(100)/20(10) plitidepsin treatment. Cells from undifferentiated tumors needed more than 3 days to recover logarithmic growth, and after 7 days, cell number was still significantly lower than in control cultures. 4(100)/20(10) plitidepsin inhibited the growth in soft agar. Together, our data show that plitidepsin is able to block in vitro cell cycle progression at concentrations similar to serum concentrations observed in vivo, and that this effect is persistent for several days after plitidepsin removal. Whether plitidepsin will prove to be clinically useful in the treatment of undifferentiated thyroid cancers remains to be established. However, our results raise the possibility that plitidepsin might be effective alone or in combination with radiotherapy and/or other drug treatments.  相似文献   
52.
The screening program of congenital hypothyroidism (CH) is probably one of the best achievements in paediatrics. Thyroid hormones are essential for brain development and brain maturation that continue through the neonatal period. Hypothyroidism that begins in the first months of life causes irreversible damage to the central nervous system, and is one of the most frequent and preventable causes of mental retardation. As children with congenital hypothyroidism are born with a normal appearance, analytical studies are required to immediately start the appropriate therapy.This article analyses the aims, diagnostic procedures, tests required, aetiology, and differential diagnosis in this disorder. Especially relevant is to perform frequent monitoring to ensure dose adjustments of L-Thyroxine therapy, avoiding infra- or supra-dosing that negatively affects neurosensory functions. Re-evaluation of the aetiology permanent vs transient hypothyroidism is always recommended after 3 years of chronological age.The relevance of this screening program should be widely discussed in paediatrics. The main objective is to avoid cerebral damage in these patients, and has been highly successful and economically beneficial.Other aspects are required to optimise patient outcomes, to perform all the controls according to the recommendations and to include, in the near future, the diagnosis of central hypothyroidism. Implementation of this program is necessary to progress in accordance with current scientific knowledge.  相似文献   
53.
ObjectiveTest effectiveness and acceptability of interventions short essay-type training in health emergency management (EM).DesignCombined case series and controlled study before and after training sessions.LocationHealth Center (HC).ParticipantsTeam on duty, two monitors-facilitators, and a mannequin.Main measuresVariables: response times, staff performance, resource usage and opinion. Structure: scenarios and key messages. Instrument development: 1. Initial/final questionnaire and events. 2. Essential/non-essential times; 3. Post-test opinion questionnaire. Performance of six consecutive 15 min tests fortnightly (including corrections) and poll after each test. A month later, repeat in random order and under similar conditions. Analysis: repeated measures.ResultsA total of 93 (2/3) workers completed the initial survey, and 74 the final, with 46 participants (25 doctors, 7 nurses, 21 non-health completed 95 direct interventions. Matching participants > 80% between series. A reduction was seen in the “detection of collapse to first defibrillation” interval (10 to 4 min). EM events improved 2-3 fold and “sense of security during a real EM” increased from 23% to 71% among participants. The vast majority of participants said “useful corrections made by the facilitator.” The proportions of those who “would like to see tests introduced” and those who said “re-training was needed in EM” were moderately increased (67.4% vs 85% in health care workers). The “would like to attempt basic life support” was unchanged.ConclusionDespite being reduced in number and duration, this model of intervention has shown positive trends in terms of use and acceptability for implementation in the HC.  相似文献   
54.
Ts65Dn mice (TS), the most commonly used model of Down syndrome (DS), exhibit phenotypic characteristics of this condition. Both TS mice and DS individuals present cognitive disturbances, age‐related cholinergic degeneration, and increased brain expression of β‐amyloid precursor protein (AβPP). These neurodegenerative processes may contribute to the progressive cognitive decline observed in DS. Melatonin is a pineal indoleamine that has been reported to reduce neurodegenerative processes and improve cognitive deficits in various animal models. In this study, we evaluated the potentially beneficial effects of long‐term melatonin treatment on the cognitive deficits, cholinergic degeneration, and enhanced AβPP and β‐amyloid levels of TS mice. Melatonin was administered for 5 months to 5‐ to 6‐month‐old TS and control (CO) mice. Melatonin treatment improved spatial learning and memory and increased the number of choline acetyltransferase (ChAT)‐positive cells in the medial septum of both TS and CO mice. However, melatonin treatment did not significantly reduce AβPP or β‐amyloid levels in the cortex or the hippocampus of TS mice. Melatonin administration did reduce anxiety in TS mice without inducing sensorimotor alterations, indicating that prolonged treatment with this indoleamine is devoid of noncognitive behavioral side effects (e.g., motor coordination, sensorimotor abilities, or spontaneous activity). Our results suggest that melatonin administration might improve the cognitive abilities of both TS and CO mice, at least partially, by reducing the age‐related degeneration of basal forebrain cholinergic neurons. Thus, chronic melatonin supplementation may be an effective treatment for delaying the age‐related progression of cognitive deterioration found in DS.  相似文献   
55.
This article briefly outlines a collaboration among communities on Hawai‘i Island and a university-based research team to develop, implement, and evaluate a school-based substance use prevention curriculum called Ho‘ouna Pono. In addition to providing a rationale for the project, the goal of this paper is fourfold. First, an overview of the Ho‘ouna Pono research results to date (2007–2013) is provided. Second, within this overview, the ways in which selected results informed program development are highlighted. Third, the curriculum is briefly described, and finally, the role of the students and community in the video production is described.  相似文献   
56.
Recent evidence suggests that miRNAs could be used as serum markers in a variety of normal and pathological conditions. In this study, we aimed to identify novel miRNAs associated with skeletal metastatic disease in a preclinical model of lung cancer bone metastasis. We assessed the validity of these miRNAs as reliable serum biochemical markers to monitor the extent of disease and response to treatment in comparison to imaging techniques and standard biochemical markers of bone turnover. Using a murine model of human lung cancer bone metastasis after zoledronic acid (ZA) treatment, PINP (procollagen I amino-terminal propeptide) was the only marker that exhibited a strong correlation with osteolytic lesions and tumor burden at early and late stages of bone colonization. In contrast, BGP (osteocalcin) and CTX (carboxyterminal telopeptide) demonstrated a strong correlation only at late stages. We performed qPCR based screening of a panel of 380 human miRNAs and quantified bone metastatic burden using micro-CT scans, X-rays and bioluminescence imaging. Interestingly, levels of miR-326 strongly associated with tumor burden and PINP in vehicle-treated animals, whereas no association was found in ZA-treated animals. Only miR-193 was associated with biochemical markers PINP, BGP and CTX in ZA-treated animals. Consistently, miR-326 and PINP demonstrated a strong correlation with tumor burden. Our findings, taken together, indicate that miR-326 could potentially serve as a novel biochemical marker for monitoring bone metastatic progression.  相似文献   
57.
Introduction and objectivesLaryngeal electromyography, together with clinical evaluation, is a valuable tool in voice disorder management. It assesses the integrity of laryngeal nerves and muscles, contributing to the diagnosis of many diseases, especially laryngeal movement disorders. Our purpose was to describe the experience of the first Spanish series with laryngeal electromyography in evaluating voice disorders.MethodsA prospective study was designed to evaluate laryngeal movement disorders with laryngeal electromyography. Both the cricothyroid and thyroarytenoid muscles were tested routinely and, in some cases, the posterior cricoarytenoid muscle. The laryngeal electromyography technique and result interpretation were performed by a laryngologist and a neurophysiologist.ResultsWe included 110 patients, with the most common symptom being dysphonia. Laryngeal electromyography was performed in 85% of cases. Primary diagnosis before electromyography was laryngeal immobility. Positive predictive value for diagnosis in cases of paralysis was 88%.ConclusionsLaryngeal electromyography is a useful adjunct, together with clinical evaluation, for diagnosis and management of motion abnormalities in the larynx in patients who present with dysphonia.  相似文献   
58.
59.
Very preterm births prevent a complete development of the nervous system. The hippocampus is especially vulnerable in this population since the perinatal period is critical for its growth and development. Learning and memory abilities, like spatial memory, depend on the hippocampal integrity. In this study we applied virtual-reality-based tasks to assess spatial memory in a sample of 20 very preterm children of 7 and 8 years of age. Two different conditions of difficulty were used. Very preterm children performed poorly in the task in comparison with the control group. They committed more errors than controls searching for the rewarded positions. However, no significant differences were observed in the mean speed, an index of the motor abilities and joystick handling. These results suggest that the hippocampal function is affected in this sample. Nevertheless, other variables to consider are discussed.  相似文献   
60.
Patients with severe mental illness have higher prevalences of cardiovascular risk factors (CRF). The objective is to determine whether interventions to modify lifestyles in these patients reduce anthropometric and analytical parameters related to CRF in comparison to routine clinical practice. Systematic review of controlled clinical trials with lifestyle intervention in Medline, Cochrane Library, Embase, PsycINFO and CINALH. Change in body mass index, waist circumference, cholesterol, triglycerides and blood sugar. Meta-analyses were performed using random effects models to estimate the weighted mean difference. Heterogeneity was determined using i2 statistical and subgroups analyses. 26 studies were selected. Lifestyle interventions decrease anthropometric and analytical parameters at 3 months follow up. At 6 and 12 months, the differences between the intervention and control groups were maintained, although with less precision. More studies with larger samples and long-term follow-up are needed.  相似文献   
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