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81.
To assess the adaptation of the heart of diabetic subjects in the natural volume overload state of pregnancy, echocardiography was performed during each trimester and postpartum in 17 women with insulin-dependent diabetes mellitus (IDDM) and in 11 healthy women. The mean duration of diabetes was 14 yr and signs of microvascular complications were detected in 6 patients. The diabetic women had slightly smaller left ventricles than the control women already in the basal state (postpartum), and the pregnancy-induced increase in left ventricular size and stroke volume was less in the diabetic than in the control women. The heart rate rise also tended to be less in the diabetic women, resulting in a markedly smaller increase in cardiac output in this group (1.3 vs. 3.4 L/min, P less than .01). Left ventricular systolic function, wall thicknesses, or left atrial size did not differ between the groups at any point in the study. Minor collections of pericardial fluid were observed in 14 (76%) diabetic women and in 5 (45%) control women during the second and/or third trimester, but only 2 diabetic women had classic pericardial effusions. In conclusion, the normal hemodynamic adjustments to pregnancy seem to be impaired in women with IDDM. Preclinical diabetic cardiomyopathy and autonomic neuropathy may be involved in the observed alterations.  相似文献   
82.

Purpose

Rupture-prone atherosclerotic plaques are characterized by accumulation of macrophages, which have shown to express somatostatin type 2 receptors. We aimed to investigate whether somatostatin receptor-targeting positron emission tomography (PET) tracers, [68Ga]DOTANOC, [18F]FDR-NOC, and [68Ga]DOTATATE, can detect inflamed atherosclerotic plaques.

Procedures

Atherosclerotic IGF-II/LDLR?/?ApoB100/100 mice were studied in vivo and ex vivo for tracer uptake into atherosclerotic plaques. Furthermore, [68Ga]DOTANOC and [68Ga]DOTATATE were compared in a head-to-head setting for in vivo PET/X-ray computed tomography (CT) imaging characteristics.

Results

Ex vivo uptake of [68Ga]DOTANOC and [68Ga]DOTATATE in the aorta was higher in atherosclerotic mice compared to control C57Bl/6N mice, while the aortic uptake of [18F]FDR-NOC showed no genotype difference. Unlike [18F]FDR-NOC, [68Ga]DOTANOC and [68Ga]DOTATATE showed preferential binding to atherosclerotic plaques with plaque-to-wall ratio of 1.7?±?0.3 and 2.1?±?0.5, respectively. However, the aortic uptake and aorta-to-blood ratio of [68Ga]DOTANOC were higher compared to [68Ga]DOTATATE in in vivo PET/CT imaging.

Conclusion

Our results demonstrate superior applicability for [68Ga]DOTANOC and [68Ga]DOTATATE in the detection of atherosclerotic plaques compared to [18F]FDR-NOC.
  相似文献   
83.
Nasal allergen challenge (NAC) is an important tool to diagnose allergic rhinitis. In daily clinical routine, experimentally, or when measuring therapeutic success clinically, nasal allergen challenge is fundamental. It is further one of the key diagnostic tools when initiating specific allergen immunotherapy. So far, national recommendations offered guidance on its execution; however, international divergence left many questions unanswered. These differences in the literature caused EAACI to initiate a task force to answer unmet needs and find a consensus in executing nasal allergen challenge. On the basis of a systematic review containing nasal allergen challenges of the past years, task force members reviewed evidence, discussed open issues, and studied variations of several subjective and objective assessment parameters to propose a standardized way of a nasal allergen challenge procedure in clinical practice. Besides an update on indications, contraindications, and preparations for the test procedure, main recommendations are a bilaterally challenge with standardized allergens, with a spray device offering 0.1 mL per nostril. A systematic catalogue for positivity criteria is given for the variety of established subjective and objective assessment methods as well as a schedule for the challenge procedure. The task force recommends a unified protocol for NAC for daily clinical practice, aiming at eliminating the previous difficulty of comparing NAC results due to unmet needs.  相似文献   
84.
BACKGROUND: Central vein leads are known to predispose to venous obstruction. Although usually asymptomatic, obstruction may render electrode removal difficult. This study aimed at quantifying changes in venous calibers in a prospective fashion by intravenous contrast venography (ICV) before and after pacemaker (PM) or cardioverter-defibrillator implantation. METHODS: One hundred and fifty (mean age 67; 61% male) consecutive patients were enrolled, and followed for 6 months. A successful ICV was done at baseline prior to implantation and at 6-month follow-up in 136 (91%) patients. Minimum (D(min)) and maximum (D(max)) vessel diameters were obtained from both ICVs. A new stenosis was defined as a 50% diameter reduction in a venous segment when compared to baseline. We implanted a total of 230 electrodes: 47 (34.6%) single lead, 84 (61.8%) 2-lead, and 5 (3.7%) 3-lead systems. RESULTS: At baseline ICV, 10 patients (7%) were found to have venous anomalies, including 8 patients with obstructive lesions, 1 patient with a persistent left superior vena cava, and 1 patient with double axillary vein. At 6 months, a new obstructive venous lesion had developed in a total of 19 (14%) patients, none of whom exhibited any local symptoms. Of these patients 14 (10%) had a stenosis (mean D(min) 4.6 mm and diameter 38% of baseline), and 5 (3.6%) had a complete venous occlusion. In most cases the new stenosis developed in a location where the vessel was narrowest at baseline. Clinical predictors for the development of stenosis were atrial fibrillation at baseline and biventricular PM implantation. CONCLUSIONS: This is the first systematic study to quantify venous changes after PM or ICD implantation. Our study shows that venous anomalies rendering PM implantation difficult are not infrequent. The incidence of new venous obstruction was 14%. Atrial fibrillation and biventricular PM implantation were independent predictors of venous obstruction.  相似文献   
85.
Baseline levels of pinoline, 6-methoxy-1,2,3,4-tetrahydro-beta-carboline (6-MeOTHBC) in the serum and cerebrospinal fluid (CSF) were determined with GLC-mass spectrometry in 13 unmedicated schizophrenic patients and 18 non-psychiatric controls. A detectable concentration of 6-MeOTHBC was always present, but no differences were found between the schizophrenic and the control groups. The serum and the CSF levels of 6-MeOTHBC were not significantly related to such variables as sex, age, subtype of schizophrenia, the quality and/or intensity of the psychopathological symptoms, or the duration of illness. The role of the indoleamines in the aetiopathogenesis of schizophrenia is discussed.  相似文献   
86.
OBJECTIVE: The purpose of this preliminary study is to evaluate the effect of various wavelengths of light on nanobacteria (NB). BACKGROUND DATA: NB and mitochondria use light for biological processes. NB have been described as multifunctional primordial nanovesicles with the potential to utilize solar energy for replication. NB produce slime, a process common to living bacteria. Slime release is an evolutionary important stress-dependent phenomenon increasing the survival chance of individual bacteria in a colony. In the cardiovascular system, stress-induced bacterial colony formation may lead to a deposition of plaque. METHODS: Cultured NB were irradiated with NASA-LEDs at different wavelengths of light: 670, 728 and 880 nm. Light intensities were about 500k Wm(-2), and energy density was 1 x 10(4) J m(-2). RESULTS: Monochromatic light clearly affected replication of NB. Maximum replication was achieved at 670 nm. CONCLUSIONS: The results indicate that suitable wavelengths of light could be instrumental in elevating the vitality level of NB, preventing the production of NB-mediated slime, and simultaneously increasing the vitality level of mitochondria. The finding could stimulate the design of cooperative therapy concepts that could reduce death caused by myocardial infarcts.  相似文献   
87.
Objective: The Finnish Medicines Agency (Fimea) initiated a programme in 2012 for enhancing interprofessional networking in the medication management of the aged. The goal is to develop national guidelines for interprofessional collaboration with respect to medication management. This study aims to explore the challenges and potential solutions experienced by existing health care teams in managing medication of the aged: (1) at the individual and team level (micro level), (2) organisational level (meso level) and (3) structural level (macro level).

Design: Group discussions (n?=?10), pair (n?=?3) and individual interviews (n?=?2). Abductive content analysis combining data and theory was applied. Networking was used as a theoretical framework.

Setting: Meetings (n?=?15) organised by Fimea in the formation phase of the interprofessional network in 2012.

Subjects: Health care professionals (n?=?55).

Main outcome measures: Challenges and solutions in the medication management of the aged at the micro, meso and macro levels.

Results: Challenges in interprofessional collaboration, problems with patient record systems, and the organisation of work and lack of resources were present at all the levels contributing to patients’ medication problems. Participants suggested multiple potential solutions to improve interprofessional collaboration, sharing of tasks and responsibilities, better exploitation of pharmaceutical knowledge and developing tools as being the most commonly mentioned.

Conclusions: Optimising medication use of the aged requires new systemic solutions within and between different system levels. The main challenges can be solved by clarifying responsibilities, enhancing communication and applying operational models that involve pharmacists and the use of information technology in medication management.
  • KEY POINTS
  • An interprofessional team approach has been suggested as a solution to promote rational medicine use among the aged.

  • Fragmented health care system and lack of coordinated patient care are reasons for medication related problems of the aged.

  • Challenges in the implementation of interprofessional collaboration in medication management appear in legislation, information systems, operational models and individuals’ attitudes.

  • Optimising medications requires better interprofessional networking and new systemic solutions within and between macro, meso and micro levels.

  相似文献   
88.

Objectives

During menopausal transition autonomic balance is known to shift towards sympathetic dominance, but the role of vasomotor hot flushes in this phenomenon is not understood. We compared cardiovascular autonomic responsiveness between women with and without hot flushes.

Study design and main outcome measures

One hundred fifty recently postmenopausal healthy women with varying degree of hot flushes (none, mild, moderate, severe) underwent comprehensive cardiovascular autonomic nervous testing (controlled and deep breathing, active orthostatic test, Valsalva manoeuvre and handgrip test) assessing both sympathetic and parasympathetic activity. The responses of heart rate, heart rate variability and blood pressure in these tests were evaluated.

Results

Responses in heart rate showed differences between the study groups only in the Valsalva manoeuvre where the tachycardia ratio in all symptomatic women was lower (p = 0.041) than in women without hot flushes. Neither change in the heart rate variability analyses nor the blood pressure responses were affected by hot flush status. However, there was a non-significantly higher maximum systolic (140 (112–182) mmHg vs. 135 (102–208) mmHg) and diastolic blood pressure (94 (72–112) mmHg vs. 90 (66–122) mmHg) following the handgrip test in women without hot flushes vs. all the symptomatic women.

Conclusions

Menopausal hot flushes seem to be associated with a possibly increased sympathetic preponderance without an effect on parasympathetic activity in cardiovascular autonomic responses. This may imply a potentially negative impact on cardiovascular health in women experiencing hot flushes.  相似文献   
89.
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