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31.
Diffusion tensor imaging (DTI) has become a useful tool for investigating early white matter (WM) abnormalities in motor neuron disease. Furthermore, fiber tracking packages that apply multi-tensorial algorithms, such as q-ball imaging (QBI), have been proposed as alternative approaches to overcome DTI limitations in depicting fiber tracts with different orientations within the same voxel. We explored motor and extra-motor WM tract abnormalities in phenotypically heterogeneous amyotrophic lateral sclerosis (ALS) cases aiming to establish a consistent QBI-based WM signature of disease. We performed a whole-brain, QBI tract-based spatial statistics analysis with deterministic tractography of genu, body and splenium of corpus callosum (CC) and corticospinal tracts (CST) in 20 ALS patients (12 classical and 8 lower motor neuron variants) compared to 20 healthy controls. Mean tract length, fiber volume and density, and generalized fractional anisotropy were extracted and related to clinical indices of pyramidal impairment (upper motor neuron score), disease disability (ALS functional rating scale-revised) and progression. ALS patients showed significantly decreased fiber density and volume, and increased tract length in all regions of CC and left CST (p < 0.05, corrected). In CC body, pyramidal impairment was inversely correlated to fiber density (p = 0.01), while in CC splenium, clinical disability (p = 0.01) and progression (p = 0.02) were inversely correlated to tract length. Our findings further suggest that QBI tractography might represent a promising approach for investigating structural alterations in neurodegenerative diseases and confirm that callosal involvement is a consistent feature of most ALS variants, significantly related to both pyramidal dysfunction and disease disability.  相似文献   
32.
HIV-1 V2 domain binds α4β7, which assists lymphocyte homing to gut-associated lymphoid tissue. This triggers bacterial translocation, thus contributing to immune activation. We investigated whether variability of V2 179-181binding site could influence plasma levels of lipopolysaccharide (LPS) and soluble cluster of differentiation 14 (sCD14), markers of microbial translocation/immune activation. HIV gp120 sequences from antiretroviral naïve patients were analyzed for V2 tripeptide composition, length, net charge, and potential N-linked-glycosylation sites. LPS and sCD14 plasma levels were quantified. Clinical/immuno-virologic data were retrieved. Overall, 174 subjects were enrolled, 8% with acute infection, 71% harboring a subtype B. LDV179-181 was detected in 41% and LDI in 27%. No difference was observed between levels of LPS or sCD14 according to different mimotopes or according to other sequence characteristics. By multivariable analysis, only acute infection was significantly associated with higher sCD14 levels. In conclusion, no association was observed between V2 tripeptide composition and extent of bacterial translocation/immune activation.  相似文献   
33.
34.

Objectives

A series of patients affected by desquamative gingivitis (DG) was investigated in order to evaluate relation patterns among clinical parameters relevant to plaque-induced periodontitis, periodontal microbiological data and the presence of DG lesions.

Patients and methods

Eight oral lichen planus (OLP) and four mucous membrane pemphigoid (MMP) patients were examined. Periodontal measurements (performed at six sites per tooth on all teeth) included probing depth (PD), gingival recession (REC), clinical attachment loss (CAL) and full-mouth plaque (FMPS) and bleeding (FMBS) scores; the presence and the exact location (site by site) of DG lesions were carefully recorded. Sub-gingival plaque samples were collected and examined by means of real-time PCR for the quantitative determination of the six most important marker organisms of periodontitis. Statistically significant differences and correlation of studied variables between DG-positive and DG-negative sites were investigated in MMP and OLP cases using Mann–Whitney test (p?<?0.05) and the Spearman rank correlation coefficient, respectively.

Results

OLP gingival lesions do not significantly affect CAL, although the presence of such lesions may reduce REC and increase PD and FMPS. MMP gingival lesions significantly worsened CAL and increased REC and FMPS. In both OLP and MMP cases, no significant difference was found between DG-positive and DG-negative sites as regards the relative percentage of the investigated species on the total bacterial load. Correlations between the presence of DG lesions and clinical parameters (CAL, PD, REC) were not significant (p?<?0.05). Significant correlations were found for the presence of gingival OLP lesions and Aggregatibacter actinomycetemcomitans (AA) and for the absence of gingival MMP lesions and AA.

Conclusions

These findings are not definitive, but highlight the need for further investigations of periodontal clinical and microbiological aspects of disorders causing DG in order to clarify their potential interference with plaque-related periodontitis.  相似文献   
35.
This monocentric, retrospective, two-stage observational study aimed to recognize the risk factors for a poor outcome in patients hospitalized with SARS-CoV-2 infection, and to develop and validate a risk score that identifies subjects at risk of worsening, death, or both. The data of patients with SARS-CoV-2 infection during the first wave of the pandemic were collected and analyzed as a derivation cohort. Variables with predictive properties were used to construct a prognostic score, which was tried out on a validation cohort enrolled during the second wave. The derivation cohort included 494 patients; the median age was 62 and the overall fatality rate was 22.3%. In a multivariable analysis, age, oxygen saturation, neutrophil-to-lymphocyte ratio, C-reactive protein and lactate dehydrogenase were independent predictors of death and composed the score. A cutoff value of 3 demonstrated a sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of 93.5%, 68.5%, 47.4% and 97.2% for death, and 84.9%, 84.5%, 79.6% and 87.9% for worsening, respectively. The validation cohort included 415 subjects. The score application showed a Se, Sp, PPV and NPV of 93.4%, 61.6%, 29.5% and 98.1% for death, and 81%, 76.3%, 72.1% and 84.1% for worsening, respectively. We propose a new clinical, easy and reliable score to predict the outcome in hospitalized SARS-CoV-2 patients.  相似文献   
36.
Hormone replacement therapy (HRT) seems to have a favorable influence on the plasma lipid profile. Only a few investigations have examined the effects of HRT versus hepatic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors. We compared the relative effects of different hypolipidemic strategies on lipoproteins and coagulative parameters in women with recent-onset spontaneous menopause. In this 24-week, placebo-controlled trial, 60 consecutive healthy women aged >/= 45 years, with amenorrhea from 6 to 60 months (mean, 1.9 +/- 1.4 years), serum follicle stimulating hormone (FSH) greater than 40 U/L, and slight to moderate hypercholesterolemia (low-density lipoprotein-cholesterol [LDL-C] 160 to 250 mg/dL, high-density lipoprotein-cholesterol [HDL-C] < 75 mg/dL, and triglycerides < 200 mg/dL) were enrolled and randomized to dietetic advice (placebo group), simvastatin 10 mg, 0.625 mg of conjugated equine estrogen (CEE), or 50 microg estrogen transdermal patch (ETP). In the latter 2 cases, the progestative nomegestrol was added to estrogens (days 17 to 28 of the cicle). Lipoprotein parameters were evaluated after separating very-low-density lipoproteins (VLDLs) by ultracentrifugation, while fasting glucose and insulin, homocysteine, and hemocoagulative parameters were determined in plasma. Fifty-four patients completed the trial. Total cholesterol (TC) and LDL-C significantly decrased in the simvastatin (-62 mg/dL [-20%] and -72 mg/dL [-30%], respectively), CEE (-42 mg/dL [-13%] and -45 mg/dL [-18%]), and ETP (-30 mg/dL [-10%] and -26 mg/dL [-11%]) groups compared to baseline, but only simvastatin showed an effect significantly superior to diet alone. Apolipoprotein (Apo) B was decreased by simvastatin (-25%, P <.001) and by CEE (-10%, P <.05); again, simvastatin was more effective than either diet or ETP. Triglyceride concentration and VLDL-C were unmodified by treatments. HDL-C and Apo A-I significantly increased in the simvastatin group (+18% and +8%, respectively), while HDL-C was unmodified by both HRT regimens and Apo A-I was reduced by ETP treatment (-17%); lipoprotein[a] (Lp[a]) was decreased by both HRTs (-38%, P <.05, and -22%, P =.07, for CEE and ETP, respectively). Among coagulative parameters, plasminogen activator inhibitor-1 (PAI-1) was significantly reduced by CEE (-29%, P <.05) but not ETP treatment (+16%, P = not significant), while fibrinogen, antithrombin, and homocysteine were unaffected by therapy. Thus, HRT, particularly CEE, seems well tolerated and moderately effective in improving the lipid pattern and, perhaps, the coagulative/fibrinolytic balance in postmenopausal hypercholesterolemic women; it may represent a therapeutic option in slightly dyslipidemic subjects. Statins are preferred in case of more severe disease.  相似文献   
37.
Objective We investigated the amino acid (AA) tolerance during Total Parenteral Nutrition (TPN) in adult patients undergone liver transplant (LTX).Design The treatment (Glucose and AA), induced on the 2nd postoperative day, was later maintained with 27 kcal/kg Ideal Body Weight (IBW) as glucose and 0.12 (12 patients: protocol #1), 0.18 (10 patients: protocol #2) and 0.25 g nitrogen (N)/kg IBW (13 patients: protocol #3) till end of the 6th postoperative day. The N intake was sequentially modified in protocol #2 and #3 to increase the supply of the amino acid (AA) that resulted in an infusion plasma level below the expected normal range (between 1 and 1.6 times the overnight fasting plasma level of volunteer).Patients 35 consecutive adult patients without diabetes and organ failures for the entire study period.Measurements: Plasma AA profile was measured before LTX and at the last TPN day under continuous infusion. During #1 and #2 protocol, many AA resulted below or at the lower range of the norm while, during 0.25 gN/kg IBW infusion, the majority of the administered AA significantly increased with respect to reference values. Nevertheless, they remained in the normal plasma range indicating that they were supplied in an optimal amount (particularly the aromatic and sulphurated ones, potentially toxic if liver function is impaired, and the branched chain AA (BCAA) given at consistent dosage: 0.5 g/kg). Arginine resulted significantly increased (Arg: 1.9 times the reference) and cystine (Cys: 0.45), serine (Ser: 0.8) and taurine (Tau: 0.85) remained significantly lower than normal as well as the not administered citrulline (Cit: 0.58) and alfa amino butyric acid (Aba: 0.41). The AA (and calorie) load almost balanced the N losses during the 5th (0.411±0.038) and 6th study day (0.305±0.019 gN/kg).Conclusions 0.25 gN/kg could be considered the minimum N load in the uncomplicated adult LTX recipients, for reassuring a balanced plasma AA pattern and body N turnover in the early postoperative phase.  相似文献   
38.
To evaluate the effect induced on gas exchange and on urea excretion by glucose and insulin infusion in injured patients. The magnitude and time necessary for the full development of the metabolic effect were investigated. Six injured patients were investigated. During the first 24 hours, the fasting period, patients received 1 mg/kg*min of glucose; during the second 24 hours, the treatment period, infusion was increased to about the 95% of the energy production rate; during the last 8 hours, (stop period) the infusion rate was again set to 1 mg/kg*min. Gas exchange was determined in two consecutive 12-hour series, for 30 minutes every hour, either during a stabilized treatment or after its variation. Urea excretion was determinated on 4-hour samples. With respect to the fasting period, during the last 4 hours of the treatment period, the energy production rate did not vary; urea excretion (−25%) and oxygen consumption (−9%) decreased significantly. Carbon dioxide production (+16%), total respiratory quotient, and minute ventilation (+5%) increased significantly. Carbon dioxide production varied linearly with time (glucose infusion +1.74 mL/min*m2*h, P <.05; glucose withdrawal −1.89 mL/min*m2*h, P < .01). Minute ventilation decreased only during the withdrawal period by 65 mL/ min*m2*h (P < .05). The infusion of glucose and insulin, in an amount slightly lower than the metabolic expenditure, leads to a consistently reduced amino acid catabolism and to a decreased oxygen consumption, without affecting energy requirements. Although it leads to an increase of carbon dioxide production, the measured change is so small and slow that it is not harmful unless there is severe respiratory insufficiency.  相似文献   
39.
Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury.  相似文献   
40.

Purpose

Pleural effusion (PE) is commonly encountered in mechanically ventilated, critically ill patients and is generally addressed with evacuation or by fluid displacement using increased airway pressure (PAW). However, except when massive or infected, clear evidence is lacking to guide its management. The aim of this study was to investigate the effect of recruitment maneuvers and drainage of unilateral PE on respiratory mechanics, gas exchange, and lung volume.

Materials and methods

Fifteen critically ill and mechanically ventilated patients with unilateral PE were enrolled. A 3-step protocol (baseline, recruitment, and effusion drainage) was applied to patients with more than 400 mL of PE, as estimated by chest ultrasound. Predefined subgroup analysis compared patients with normal vs reduced chest wall compliance (CCW). Esophageal and PAWs, respiratory system, lung and CCWs, arterial blood gases, and end-expiratory lung volumes were recorded.

Results

In the whole case mix, neither recruitment nor drainage improved gas exchange, lung volume, or tidal mechanics. When CCW was normal, recruitment improved lung compliance (81.9 [64.8-104.1] vs 103.7 [91.5-111.7] mL/cm H2O, P < .05), whereas drainage had no significant effect on total respiratory system mechanics or gas exchange, although it measurably increased lung volume (1717 vs 2150 mL, P < .05). In the setting of reduced CCW, however, recruitment had no significant effect on total respiratory system mechanics or gas exchange, whereas pleural drainage improved respiratory system and CCWs as well as lung volume (42.7 [38.9-50.0] vs 47.0 [43.8-63.3], P < .05 and 97.4 [89.3-97.9] vs 126.7 [92.3-153.8] mL/cm H2O, P < .05 and 1580 vs 1750 mL, P < .05, respectively).

Conclusions

Drainage of a moderate-sized effusion should not be routinely performed in unselected population of critically ill patients. We suggest that measurement of CCW may help in the decision-making process.  相似文献   
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