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91.

Introduction

Communication between pulp and periodontal tissue has been well established. However, it is unknown when periodontal disease begins to affect the clinical response of pulp tissue. The aim of this study was to assess the influence of periodontal severity on pulp sensibility by means of electric and thermal cold testing.

Methods

The teeth assessed in this study were allocated into 3 groups considering radiographic alveolar bone loss (ABL) as follows: slight periodontitis (SP, ABL ≤7 mm without reaching the apex, n = 25), moderate periodontitis (ABL >7 mm without reaching the apex, n = 23), and severe periodontitis (SvP, ABL >7 reaching the apex, n = 8). Gingival recession (GR), probing depth (PD), and clinical attachment level (CAL) were also measured.

Results

The results showed higher levels of PD and CAL in the SvP group compared with the SP group (P < .05), with no significant difference in GR (P > .05). The SvP group showed significant ABL compared with the other groups (P > .05). The SP group showed a significant number of teeth with a positive pulp response, whereas the SvP group showed a significant number of teeth with a negative pulp response (P < .05); no significant differences were observed between the thermal cold and electric tests (P > .05).

Conclusions

Within the limits of this study, it can be concluded that pulp clinical involvement with a negative response to thermal cold and electric testing occurs only in the most advanced stage of chronic periodontitis with apical involvement.  相似文献   
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The cystine/glutamate antiporter is a membrane transport system responsible for the uptake of extracellular cystine and release of intracellular glutamate. It is the major source of cystine in most cells, and a key regulator of extrasynaptic glutamate in the CNS. Because cystine is the limiting factor in the biosynthesis of glutathione, and glutamate is the most abundant neurotransmitter, the cystine/glutamate antiporter is a central player both in antioxidant defense and glutamatergic signaling, two events critical to brain function. However, distribution of cystine/glutamate antiporter in CNS has not been well characterized. Here, we analyzed expression of the catalytic subunit of the cystine/glutamate antiporter, xCT, by immunohistochemistry in histological sections of the forebrain and spinal cord. We detected labeling in neurons, oligodendrocytes, microglia, and oligodendrocyte precursor cells, but not in GFAP+ astrocytes. In addition, we examined xCT expression and function by qPCR and cystine uptake in primary rat cultures of CNS, detecting higher levels of antiporter expression in neurons and oligodendrocytes. Chronic inhibition of cystine/glutamate antiporter caused high toxicity to cultured oligodendrocytes. In accordance, chronic blockage of cystine/glutamate antiporter as well as glutathione depletion caused myelin disruption in organotypic cerebellar slices. Finally, mice chronically treated with sulfasalazine, a cystine/glutamate antiporter inhibitor, showed a reduction in the levels of myelin and an increase in the myelinated fiber g‐ratio. Together, these results reveal that cystine/glutamate antiporter is expressed in oligodendrocytes, where it is a key factor to the maintenance of cell homeostasis. GLIA 2016. GLIA 2016;64:1381–1395  相似文献   
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Introduction and objectivesCardiac amyloidosis (CA) is produced by amyloid fiber deposition in the myocardium. The most frequent forms are those caused by light chains (AL) and transthyretin (ATTR). Our objective was to describe the diagnosis, treatment and outcomes of CA in a specialized Spanish center.MethodsWe included all patients diagnosed with CA in Hospital Universitario Puerta de Hierro Majadahonda from May 2008 to September 2018. We analyzed their clinical characteristics, outcomes, and survival.ResultsWe included 180 patients with CA, of whom 64 (36%) had AL (50% men; mean age, 65 ± 11 years) and 116 had ATTR (72% men; mean age 79 ± 11 years; 18 with hereditary ATTR). The most common presentation was heart failure in both groups (81% in AL and 45% in ATTR, P < .01). Other forms of presentation in ATTR patients were atrial arrhythmias (16%), conduction disorders (6%), and incidental finding (6%); 70 patients (40%), had a previous alternative cardiac diagnosis. Diagnosis was noninvasive in 75% of ATTR patients. Diagnostic delay was higher in ATTR (2.8 ± 4.3 vs 0.6 ± 0.7 years, P < .001), but mortality was greater in AL patients (48% vs 32%, P = .028). Independent predictors of mortality were AL subtype (HR, 6.16; 95%CI, 1.56-24.30; P = .01), female sex (HR, 2.35; 95%CI,1.24-4.46; P = .01), and NYHA functional class III-IV (HR, 2.07; 95%CI, 1.11-3.89; P = .02).ConclusionsCA is a clinical challenge, with wide variability in its presentation depending on the subtype, leading to diagnostic delay and high mortality. Improvements are needed in the early diagnosis and treatment of these patients.  相似文献   
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An adenosine diphosphate sugar pyrophosphatase (ASPPase, EC ) has been characterized by using Escherichia coli. This enzyme, whose activities in the cell are inversely correlated with the intracellular glycogen content and the glucose concentration in the culture medium, hydrolyzes ADP-glucose, the precursor molecule of glycogen biosynthesis. ASPPase was purified to apparent homogeneity (over 3,000-fold), and sequence analyses revealed that it is a member of the ubiquitously distributed group of nucleotide pyrophosphatases designated as "nudix" hydrolases. Insertional mutagenesis experiments leading to the inactivation of the ASPPase encoding gene, aspP, produced cells with marginally low enzymatic activities and higher glycogen content than wild-type bacteria. aspP was cloned into an expression vector and introduced into E. coli. Transformed cells were shown to contain a dramatically reduced amount of glycogen, as compared with the untransformed bacteria. No pleiotropic changes in the bacterial growth occurred in both the aspP-overexpressing and aspP-deficient strains. The overall results pinpoint the reaction catalyzed by ASPPase as a potential step of regulating glycogen biosynthesis in E. coli.  相似文献   
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Introduction and objectivesMalnutrition has been shown to affect clinical outcomes in patients with heart failure. The aim of this study was to analyze the impact of preoperative nutritional status assessed by the nutritional risk index (NRI) on the prognosis of patients with a continuous-flow left ventricular assist device (cf-LVAD).MethodsWe performed a retrospective study of 279 patients who underwent cf-LVAD implantation between 2009 and 2015 in our center. Preoperative NRI was calculated and the patients were followed-up for 1 year. The association between preoperative NRI and postoperative clinical events was analyzed using multivariable logistic regression.ResultsThe prevalence of severe (NRI < 83.5), moderate (83.5 ≤ NRI < 97.5) and mild (97.5 ≤ NRI < 100) nutritional risk was 5.4%, 21.5%, and 9.3%. Mortality rates 1 year after cf-LVAD implantation in these 3 categories were 53.3%, 31.7%, 23.1% vs 18.0% (P < .001) in patients with a normal IRN. A normal preoperative NRI value was an independent predictor of lower risk of death from any cause during follow-up (aHR per 1 unit, 0.961; 95%CI, 0.941-0.981; P < .001) was and a predictor for a lower risk of postoperative infections (aOR, 0.968; 95%CI, 0.946-0.991; P = .007), respiratory failure (aOR, 0,961; 95%CI, 0.936-0.987; P = .004), and right heart failure (aOR, 0.963; 95%CI, 0.934-0.992; P = .014).ConclusionsMalnourished patients are at increased risk for postoperative complications and death after cf-LVAD implantation. Assessment of nutritional risk could improve patient selection and the early initiation of nutritional support.Full English text available from: www.revespcardiol.org/en  相似文献   
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The purpose of this study was to investigate smart features required for the next generation of personal protective equipment (PPE) for firefighters in Australia, Korea, Japan, and the USA. Questionnaire responses were obtained from 167 Australian, 351 Japanese, 413 Korean, and 763 U.S. firefighters (1,611 males and 61 females). Preferences concerning smart features varied among countries, with 27% of Korean and 30% of U.S. firefighters identifying ‘a location monitoring system’ as the most important element. On the other hand, 43% of Japanese firefighters preferred ‘an automatic body cooling system’ while 21% of the Australian firefighters selected equally ‘an automatic body cooling system’ and ‘a wireless communication system’. When asked to rank these elements in descending priority, responses across these countries were very similar with the following items ranked highest: ‘a location monitoring system’, ‘an automatic body cooling system’, ‘a wireless communication system’, and ‘a vision support system’. The least preferred elements were ‘an automatic body warming system’ and ‘a voice recording system’. No preferential relationship was apparent for age, work experience, gender or anthropometric characteristics. These results have implications for the development of the next generation of PPE along with the international standardisation of the smart PPE.  相似文献   
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