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Deep tissue injuries are pressure ulcers which initiate in the subcutaneous tissues and extend through a bottom‐up pathway. Once deep tissue injuries are visual at skin level, serious irreversible tissue damage has already occurred. In pressure ulcer development, inflammation and edema are coupled physiological processes associated with tissue damage arising due to sustained mechanical loading. This study aimed to provide an in‐depth overview of the physiological processes of inflammation and edema initiated by sustained mechanical loading in subcutaneous tissues, in the context of pressure ulceration. A scoping review was performed according to the framework by Arksey and O'Malley. The databases MEDLINE, EMBASE, Web of Science, and Scopus, and the reference lists of included studies were searched for in vivo (animal, human), and in vitro studies matching the study objectives (from inception to 28 May 2018). No restrictions for inclusion were applied for study design, setting, participants, and year of publication. A total of 12 studies were included, varying in study design, sample characteristics, amount and duration of mechanical loads that were applied, follow‐up time, and assessment methods. Neutrophil infiltration and edema occur in the subcutaneous tissues nearly immediately after the application of load on soft tissues. The amount of neutrophils and edema increase in the first days after the mechanical insult and decrease once healing has been initiated and no supplementary mechanical load was applied. One study indicated that edema may extend up to the level of the dermo‐epidermal junction. Further research should focus on how deep tissue inflammation and edema are reflected into unique tissue changes at skin level, and how abnormal inflammatory responses manifest (e.g. when the nervous system is not functioning normally).  相似文献   
84.
Variation in the shape of the glenoid and periarticular anatomy of the scapula has been associated with shoulder pathology. The goal of this study was to identify the modes of shape variation of periarticular scapular anatomy in relation to the glenoid in nonpathologic shoulders. Computed tomography scans of 31 cadaveric scapulae, verified to be free of pathology, were three-dimensionally reconstructed. Statistical shape modeling and principal component analysis identified the modes of shape variation across the population. Corresponding linear and angular measurements quantified the morphometric variance identified by the modes. Linear measures were normalized to the radius of the inferior glenoid to account for differences in the scaling of the bones. Five modes captured 89.7% of total shape variation of the glenoid and periarticular anatomy. Apart from size differences (mode 1: 33.0%), acromial anatomy accounted for the largest variation (mode 2: 32.0%). Further modes described variation in glenoid inclination (mode 3: 11.8%), coracoid orientation and size (mode 4: 9.0%), and variation in coracoacromial (CA) morphology (mode 5: 3.1%). The average scapula had a mean acromial tilt of 49 ± 7°, scapular spine angle of 61 ± 6°, the glenoid inclination of 84 ± 4°, coracoid deviation angle of 26 ± 4°, coracoid length of 3.7 ± 0.3 glenoid radii, and a CA base length of 5.6 ± 0.5 radii. In this study, the identified shape modes explain almost all of the variance in scapular anatomy. The acromion exhibited the highest variance of all periarticular anatomic structures of the scapula in relation to the glenoid, which may play a role in many shoulder pathologies.  相似文献   
85.
Evidence suggests that affect plays a role in the development of psychosis but the underlying mechanism requires further investigation. This study examines the moment-to-moment dynamics between negative affect (NA) and paranoia prospectively in daily life. A female general population sample (n = 515) participated in an experience sampling study. Time-lagged analyses between increases in momentary NA and subsequent momentary paranoia were examined. The impact of childhood adversity, stress sensitivity (impact of momentary stress on momentary NA), and depressive symptoms on these time-lagged associations, as well as associations with follow-up self-reported psychotic symptoms (Community Assessment of Psychic Experiences and the Symptom Checklist-90-Revised) were investigated. Moments of NA increase resulted in a significant increase in paranoia over 180 subsequent minutes. Both stress sensitivity and depressive symptoms impacted on the transfer of NA to paranoia. Stress sensitivity moderated the level of increase in paranoia during the initial NA increase, while depressive symptoms increased persistence of paranoid feelings from moment to moment. Momentary paranoia responses to NA increases were associated with follow-up psychotic symptoms. Examination of microlevel momentary experience may thus yield new insights into the mechanism underlying co-occurrence of altered mood states and psychosis. Knowledge of the underlying mechanism is required in order to determine source and place where remediation should occur.Key words: momentary assessment methodology, stress, childhood adversity, psychotic symptoms, depressive symptoms  相似文献   
86.

Purpose

Since glomerular filtration rate (GFR) is responsible for the elimination of a large number of water-soluble drugs, the aim of this study was to develop a semi-physiological function for GFR maturation from neonates to adults.

Methods

In the pharmacokinetic analysis (NONMEM VI) based on data of gentamicin, tobramycin and vancomycin collected in 1,760 patients (age 1 day–18 years, bodyweight 415 g–85 kg), a distinction was made between drug-specific and system-specific information. Since the maturational model for clearance is considered to contain system-specific information on the developmental changes in GFR, one GFR maturational function was derived for all three drugs.

Results

Simultaneous analysis of these three drugs showed that maturation of GFR mediated clearance from preterm neonates to adults was best described by a bodyweight-dependent exponent (BDE) function with an exponent varying from 1.4 in neonates to 1.0 in adults (ClGFR?=?Cldrug*(BW/4 kg)BDE with BDE?=?2.23*BW?0.065). Population clearance values (Cldrug) for gentamicin, tobramycin and vancomycin were 0.21, 0.28 and 0.39 L/h for a full term neonate of 4 kg, respectively.

Discussion

Based on an integrated analysis of gentamicin, tobramycin and vancomycin, a semi-physiological function for GFR mediated clearance was derived that can potentially be used to establish evidence based dosing regimens of renally excreted drugs in children.  相似文献   
87.
88.
In this double-blind randomized placebo-controlled trial involving 30 healthy male volunteers we investigated the acute effects of iron loading (single dose of 1.25 mg/kg iron sucrose) and iron chelation therapy (single dose of 30 mg/kg deferasirox) on iron parameters, oxidative stress, the innate immune response, and subclinical organ injury during experimental human endotoxemia. The administration of iron sucrose induced a profound increase in plasma malondialdehyde 1 h after administration (433±37% of baseline; P<0.0001), but did not potentiate the endotoxemia-induced increase in malondialdehyde, as was seen 3 h after endotoxin administration in the placebo group (P=0.34) and the iron chelation group (P=0.008). Endotoxemia resulted in an initial increase in serum iron levels and transferrin saturation that was accompanied by an increase in labile plasma iron, especially when transferrin saturation reached levels above 90%. Thereafter, serum iron decreased to 51.6±9.7% of baseline at T=8 h in the placebo group versus 84±15% and 60.4±8.9% of baseline at 24 h in the groups treated with iron sucrose and deferasirox, respectively. No significant differences in the endotoxemia-induced cytokine response (TNF-α, IL-6, IL-10 and IL-1RA), subclinical vascular injury and kidney injury were observed between groups. However, vascular reactivity to noradrenalin was impaired in the 6 subjects in whom labile plasma iron was elevated during endotoxemia as opposed to those in whom no labile plasma iron was detected (P=0.029). In conclusion, a single dose of iron sucrose does not affect the innate immune response in a model of experimental human endotoxemia, but may impair vascular reactivity when labile plasma iron is formed. (Clinicaltrials.gov identifier:01349699)  相似文献   
89.

Background

Levels of atherogenic lipoproteins achieved with statin therapy are highly variable, but the consequence of this variability for cardiovascular disease risk is not well-documented.

Objectives

The aim of this meta-analysis was to evaluate: 1) the interindividual variability of reductions in low-density lipoprotein cholesterol (LDL-C), non–high-density lipoprotein cholesterol (non-HDL-C), or apolipoprotein B (apoB) levels achieved with statin therapy; 2) the proportion of patients not reaching guideline-recommended lipid levels on high-dose statin therapy; and 3) the association between very low levels of atherogenic lipoproteins achieved with statin therapy and cardiovascular disease risk.

Methods

This meta-analysis used individual patient data from 8 randomized controlled statin trials, in which conventional lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up.

Results

Among 38,153 patients allocated to statin therapy, a total of 6,286 major cardiovascular events occurred in 5,387 study participants during follow-up. There was large interindividual variability in the reductions of LDL-C, non-HDL-C, and apoB achieved with a fixed statin dose. More than 40% of trial participants assigned to high-dose statin therapy did not reach an LDL-C target <70 mg/dl. Compared with patients who achieved an LDL-C >175 mg/dl, those who reached an LDL-C 75 to <100 mg/dl, 50 to <75 mg/dl, and <50 mg/dl had adjusted hazard ratios for major cardiovascular events of 0.56 (95% confidence interval [CI]: 0.46 to 0.67), 0.51 (95% CI: 0.42 to 0.62), and 0.44 (95% CI: 0.35 to 0.55), respectively. Similar associations were observed for non-HDL-C and apoB.

Conclusions

The reductions of LDL-C, non-HDL-C, and apoB levels achieved with statin therapy displayed large interindividual variation. Among trial participants treated with high-dose statin therapy, >40% did not reach an LDL-C target <70 mg/dl. Patients who achieve very low LDL-C levels have a lower risk for major cardiovascular events than do those achieving moderately low levels.  相似文献   
90.
Atopobium species are Gram-positive, anaerobic, catalase-negative, fastidious bacteria belonging to the family Coriobacteriaceae. We report the isolation of an Atopobium-like species in a patient with Fournier''s gangrene and highlight the role of 16S rRNA gene sequencing in the identification of fastidious organisms in the clinical laboratory.  相似文献   
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