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1.

Background

The detection of early neuropsychological abnormalities as precursors of cognitive decline of vascular origin in patients with lacunar stroke is a subject of increasing interest. The objective of this study was to assess whether there were differences in the performance of a battery of neuropsychological tests in first-ever lacunar stroke patients with and without associated silent multiple lacunar infarctions found incidentally on the brain magnetic resonance imaging (MRI) scan.

Methods

A total of 72 consecutive patients with first-ever lacunar infarction were studied 1 month after stroke. All patients underwent a comprehensive neuropsychological evaluation, which included the California Verbal Learning Test (CVLT), Phonetic Verbal Fluency Test (PMR), Semantic Verbal Fluency Test (category “animals”), Digit Span Forward and Backward from the Wechsler Adult Intelligence Scale (WAIS-III), and Mini-Mental State Examination (MMSE).

Results

A total of 38 patients (52.7%) had silent multiple lacunar infarcts, with corona radiata as the most frequent topography (P?<?0.023). White matter hyperintensities (leukoaraiosis) were observed in 81.1% of patients with silent multiple lacunar infarcts and in 50% with a single lacunar infarction (P?<?0.007). Patients in both groups showed similar scores in the MMSE, but those with associated silent lacunar infarctions showed a poorer performance in the semantic fluency test (P?<?0.008) and in short delayed verbal memory (P?<?0.001). In both cases, however, leukoaraiosis was not statistically significant in multivariate linear regression models adjusted by confounding covariates. In these models, multiple silent lacunar infarctions and education were independent predictors of poor performance in the semantic fluency test and in short delayed verbal memory.

Conclusions

The presence of silent multiple lacunar infarctions documented on brain MRI scans in patients with first-ever lacunar stroke was associated with mild neuropsychological abnormalities, particularly in the performance of executive functions (semantic fluency) and short delayed verbal memory. According to these findings, in the initial stages of small vessel disease, mild neuropsychological abnormalities appear to be related to lacunes rather than to leukoaraiosis or perivascular hyperintensities of vascular cause.
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2.
The current study was conducted to provide normative data on actigraphic dichotomy index (I?<?O) (the percentage of in bed activity counts that are less than the median of out of bed counts) in healthy population and to assess whether the I?<?O could be an effective index in discriminating the circadian motor activity of cancer patients from healthy controls. In this retrospective study, we recovered 408 actigraphic records from two databases: healthy controls (n?=?182; 79 males; mean age 38.7?±?12.6) and patients with metastatic colorectal cancer (n?=?226; 149 males; mean age 58.4?±?11.4). Beside the usual actigraphic sleep parameters (time in bed, sleep onset latency, total sleep time, wake after sleep onset, sleep efficiency, number of awakenings, and mean motor activity), we also computed the dichotomy index and number of actigraphic wake parameters, namely, diurnal motor activity, diurnal total sleep time, number of sleep episodes, and the mean duration of the longest diurnal sleep episode. Using the Youden index, we calculated the cut off value that performed the best for I?<?O and actigraphic wake parameters. Finally, we created Receiver Operator Characteristic curves to test the efficacy of each actigraphic parameter to discriminate cancer patient from healthy controls. Mean I?<?O was 99.5% (SD, 0.48%) in the healthy group, as compared to 96.6% (SD, 3.6%) in the cancer group (p?<?0.0001). Important age-related effects appeared unlikely after performing both the main analysis with age as a covariate, and a subset analysis in 104 subjects matched for age and sex. In the main analysis, all actigraphic parameters, except total sleep time, significantly differentiated the two groups of participants. However, the I?<?O was the one that clearly performed best. Here, we provide the first large dataset on I?<?O in healthy subjects, we confirm the relevance of this circadian index for discriminating advanced stage colorectal cancer patients from healthy subjects, and we lay the grounds for further investigations of this circadian index in patients with other chronic diseases.  相似文献   

3.

Introduction

Diabetes mellitus is a key predictor of mortality in rheumatoid arthritis (RA) patients. Both RA and diabetes increase the risk of cardiovascular disease (CVD), yet understanding of how comorbid RA impacts the receipt of guideline-based diabetes care is limited. The purpose of this study was to examine how the presence of RA affected hemoglobin A1C (A1c) and lipid measurement in older adults with diabetes.

Methods

Using a retrospective cohort approach, we identified beneficiaries ≥65 years old with diabetes from a 5% random national sample of 2004 to 2005 Medicare patients (N = 256,331), then examined whether these patients had comorbid RA and whether they received guideline recommended A1c and lipid testing in 2006. Multivariate logistic regression was used to examine the effect of RA on receiving guideline recommended testing, adjusting for baseline sociodemographics, comorbidities and health care utilization.

Results

Two percent of diabetes patients had comorbid RA (N = 5,572). Diabetes patients with comorbid RA were more likely than those without RA to have baseline cardiovascular disease (such as 17% more congestive heart failure), diabetes-related complications including kidney disease (19% higher), lower extremity ulcers (77% higher) and peripheral vascular disease (32% higher). In adjusted models, diabetes patients with RA were less likely to receive recommended A1c testing (odds ratio (OR) 0.84, CI 0.80 to 0.89) than those without RA, but were slightly more likely to receive lipid testing (OR 1.08, CI 1.01 to 1.16).

Conclusions

In older adults with diabetes, the presence of comorbid RA predicted lower rates of A1c testing but slightly improved lipid testing. Future research should examine strategies to improve A1c testing in patients with diabetes and RA, in light of increased CVD and microvascular risks in patients with both conditions.  相似文献   

4.
Multidrug resistance (MDR) is an obstacle in cancer treatment. An understanding of how tumoral cells react to oxidants can help us elucidate the cellular mechanism involved in resistance. Microcystins are cyanobacteria hepatotoxins known to generate oxidative stress. The aim of this study was to compare the sensitivity to microcystins of human tumoral cell lines with (Lucena) and without (K562) MDR phenotype. Endpoints analyzed were effective microcystins concentration to 50% of exposed cells (EC50), antioxidant enzyme activity, lipid peroxidation, DNA damage, reactive oxygen species (ROS) concentration, and tubulin content. Lucena were more resistant and showed lower DNA damage than K562 cells (P<0.05). Although microcystins did not alter catalase activity, a higher mean value was observed in Lucena than in K562 cells. Lucena cells also showed lower ROS concentration and higher tubulin content. The higher metabolism associated with the MDR phenotype should increase ROS concentration and make for an improved antioxidant defense against the toxic effects of microcystins.  相似文献   

5.
Changes in haematocrit values under lowered oxygen tension and aerobically treated blood samples of rainbow trout Salmo gairdneri (Richardson), landlocked Baltic salmon S. salar (L.), brown trout S. trutta lacustris (L.) and lake trout Salvelinus namaycush (Walbaum) have been studied in vitro . The mean haematocrit value increased during 2 h incubation under lowered oxygen tension by 32.7 ± 3.1% in rainbow trout, 28.2 ± 2.8% in landlocked Baltic salmon, 29.2 ± 5.6% in brown trout and 25.2 ± 2.8% in lake trout. During corresponding incubation with oxygen the mean haematocrit value decreased below the starting level by 18.1 ± 1.9% in rainbow trout, 18.3 ± 4.8% in landlocked Baltic salmon, 22.4 ± 0.7% in brown trout and 11.8 ± 1.7% in lake trout. Consequently, the changes in the haematocrit values were greater in the species belonging to the genus Salmo than in that of the genus Salvelinus . The increase in the haematocrit values seems to have resulted from swelling of the erythrocytes and their decrease is similarly attributable to shrinking of the cells. The reasons for this swelling, which may be complicated, and its apparent significance for haematocrit determinations are discussed.  相似文献   

6.
Crouau Y 《Tissue & cell》1990,22(2):245-258
Three different sensory organs (one mechanoreceptor, one chemoreceptor and one chemo-mechanoreceptor) of the antennae of the cavernicolous Coleoptera Speonomus hydrophilus and S. zophosinus have been compared by means of electron microscopy after chemical fixation or cryofixation without cryoprotectant; when cryofixation succeeds, cells and organelles have a different appearance from the chemically fixed ones: they have rounded and smooth outlines and are more electron-dense; some very fine details, such as tubulinc sub-units of microtubules, are perceptible after cryofixation only. However, chemical fixation gives much more reproducible results than cryofixation; moreover, when good cryofixation is achieved preservation of cells and organelles is satisfactory only for the peripheral region; large ice-crystals more or less destroying the central zone, except the nerves. In short, chemical fixation and cryofixation appear as complementary techniques: chemical fixation must be used as a routine fixation and cryofixation when specially good cell and molecular preservation must be achieved for peripheral tissues only.  相似文献   

7.
Background:Disability-related considerations have largely been absent from the COVID-19 response, despite evidence that people with disabilities are at elevated risk for acquiring COVID-19. We evaluated clinical outcomes in patients who were admitted to hospital with COVID-19 with a disability compared with patients without a disability.Methods:We conducted a retrospective cohort study that included adults with COVID-19 who were admitted to hospital and discharged between Jan. 1, 2020, and Nov. 30, 2020, at 7 hospitals in Ontario, Canada. We compared in-hospital death, admission to the intensive care unit (ICU), hospital length of stay and unplanned 30-day readmission among patients with and without a physical disability, hearing or vision impairment, traumatic brain injury, or intellectual or developmental disability, overall and stratified by age (≤ 64 and ≥ 65 yr) using multivariable regression, controlling for sex, residence in a long-term care facility and comorbidity.Results:Among 1279 admissions to hospital for COVID-19, 22.3% had a disability. We found that patients with a disability were more likely to die than those without a disability (28.1% v. 17.6%), had longer hospital stays (median 13.9 v. 7.8 d) and more readmissions (17.6% v. 7.9%), but had lower ICU admission rates (22.5% v. 28.3%). After adjustment, there were no statistically significant differences between those with and without disabilities for in-hospital death or admission to ICU. After adjustment, patients with a disability had longer hospital stays (rate ratio 1.36, 95% confidence interval [CI] 1.19–1.56) and greater risk of readmission (relative risk 1.77, 95% CI 1.14–2.75). In age-stratified analyses, we observed longer hospital stays among patients with a disability than in those without, in both younger and older subgroups; readmission risk was driven by younger patients with a disability.Interpretation:Patients with a disability who were admitted to hospital with COVID-19 had longer stays and elevated readmission risk than those without disabilities. Disability-related needs should be addressed to support these patients in hospital and after discharge.

A successful public health response to the COVID-19 pandemic requires accurate and timely identification of, and support for, high-risk groups. There is increasing recognition that marginalized groups, including congregate care residents, racial and ethnic minorities, and people experiencing poverty, have elevated incidence of COVID-19.1,2 Older age and comorbidities such as diabetes are also risk factors for severe COVID-19 outcomes.3,4 One potential high-risk group that has received relatively little attention is people with disabilities.The World Health Organization estimates there are 1 billion people with disabilities globally.5 In North America, the prevalence of disability is 20%, with one-third of people older than 65 years having a disability.6 Disabilities include physical disabilities, hearing and vision impairments, traumatic brain injury and intellectual or developmental disabilities.5,6 Although activity limitations experienced by people with disabilities are heterogeneous,5,6 people with disabilities share high rates of risk factors for acquiring COVID-19, including poverty, residence in congregate care and being members of racialized communities.79 People with disabilities may be more reliant on close contact with others to meet their daily needs, and some people with disabilities, especially intellectual developmental disabilities, may have difficulty following public health rules. Once they acquire SARS-CoV-2 infection, people with disabilities may be at risk for severe outcomes because they have elevated rates of comorbidities.10 Some disabilities (e.g., spinal cord injuries and neurologic disabilities) result in physiologic changes that increase vulnerability to respiratory diseases and may mask symptoms of acute respiratory disease, which may delay diagnosis.1113 There have also been reports of barriers to high-quality hospital care for patients with disabilities who have COVID-19, including communication issues caused by the use of masks and restricted access to support persons.1417Some studies have suggested that patients with disabilities and COVID-19 are at elevated risk for severe disease and death, with most evaluating intellectual or developmental disability.13,1826 Yet, consideration of disability-related needs has largely been absent from the COVID-19 response, with vaccine eligibility driven primarily by age and medical comorbidity, limited accommodations made for patients with disabilities who are in hospital, and disability data often not being captured in surveillance programs.1417 To inform equitable pandemic supports, there is a need for data on patients with a broad range of disabilities who have COVID-19. We sought to evaluate standard clinical outcomes in patients admitted to hospital with COVID-1927 (i.e., in-hospital death, intensive care unit [ICU] admission, hospital length of stay and unplanned 30-d readmission) for patients with and without a disability, overall and stratified by age. We hypothesized that patients with a disability would have worse outcomes because of a greater prevalence of comorbidities,10 physiologic characteristics that increase morbidity risk1113 and barriers to high-quality hospital care.1417  相似文献   

8.
The catalytic activity of amyloglucosidase covalently attached to DEAE-cellulose was studied in a packed bed reactor and a continuous feed stirred tank reactor (CSTR) for the reaction maltose → glucose. At low flow rates mass-transfer limitations in the bed reactor lead to lower conversions for this reactor compared to the CSTR. Simple theoretical expressions for these reactors were compared with the experimental results. There are significant differences between the kinetic parameters and pH profile of the immobilized and free enzyme. The immobilized enzyme also showed greater stability at 50°C than did free amyloglucosidase. The temperature dependence of the reaction rate was the same for immobilized and free enzyme.  相似文献   

9.
10.

Background  

Efficient and accurate prediction of protein function from sequence is one of the standing problems in Biology. The generalised use of sequence alignments for inferring function promotes the propagation of errors, and there are limits to its applicability. Several machine learning methods have been applied to predict protein function, but they lose much of the information encoded by protein sequences because they need to transform them to obtain data of fixed length.  相似文献   

11.
FULLER, R. M., 1989. Orfordness and Dungeness: a comparative study . Dungeness originally developed as a shingle spit from Winchelsea, across the bay which now forms the Romney Marshes and, 700–800 years ago, probably had its distal end between New Romney and Hythe. The structure seems to have been very similar to present-day Orfordness. Then a breach at the spit's origin produced an abrupt change in accretion and erosion patterns with the eventual development of the present-day cuspate foreland. It would seem that Orfordness is on the verge of such a breach, which is prevented by coastal defence works. Much can be learned by comparing physiographic and ecological processes at Orfordness with those at Dungeness, using Orfordness as an historical model for early Dungeness. This paper considers some of the evidence for these conclusions, examines the structures which survive to the present-day and discusses the ecological significance of the features, especially in terms of plant successional developments.  相似文献   

12.
Lactoferrin and transferrin: a comparative study   总被引:27,自引:0,他引:27  
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13.
BackgroundThe scapula locator method has associated intra-observer and inter-observer errors caused by the dependency on the observer to locate the scapular landmarks. The potential effect of the pressures applied by the observer on the measured scapular kinematics when this method is used has also been overlooked so far. The aim of this study was to investigate the effect of using feedback on the pressures applied on the scapula using the locator on the intra-observer and inter-observer reliabilities of the method as well as on the kinematics obtained using this method.MethodsThree observers tracked the scapular motion of the dominant shoulder of each subject using the locator with no reference to pressure-feedback for three trials of bilateral elevation in the scapular plane and using the locator with pressure-feedback for three other trials. Variations between the measurements obtained were used to calculate the intra-observer errors and variations between the measurements obtained by the three observers for the same subject were used to calculate inter-observer errors. Repeated-measures ANOVA tests were used to look at differences between the two methods in terms of intra-observer and inter-observer errors and scapular kinematics.FindingsUsing pressure-feedback reduced the intra-observer errors but had no effect on the inter-observer errors. Different scapular kinematics was measured using the two methods.InterpretationsPressure-feedback improves the reliability of the scapula locator method. Differences in the scapular kinematics suggest that unregulated pressures have an effect on the physiological scapular motion.  相似文献   

14.
15.
Although rapid screening of negative and inadequate cervical smears is a quality assurance requirement for all UK laboratories, there has been little attempt to standardize the method and laboratories make use of a number of different techniques and times. The aim of this study was to assess the sensitivity of these various techniques by measuring their ability to pick out known false-negative smears. Completed questionnaires from 123 laboratories across England revealed that 52% of laboratories use a "step" technique, 19% use "turret", 15% use random paths and 34% attempt to rescreen the whole slide quickly. Twenty-two percent of laboratories use a mixture of techniques. Timings are also variable, with the majority of laboratories allowing screeners to review slides at a pace decided by themselves but usually between 1 and 2 min. The study involved 120 participants who performed a total of 24 000 rapid screens. The results showed that, of the 90 abnormal slides used in the study, 62 cases (69%) were identified as abnormal or needing review by more than 50% of participants. Overall rapid screening picked out 58% of high-grade squamous abnormalities, 59% of low-grade abnormalities and 72% of glandular lesions. Step screening performed best, followed by whole slide/random and then turret. One minute was the optimum time and there was a significant fall in performance once individuals attempted to rescreen large numbers (>50). The most significant finding was the marked variation in the performance of individuals using the same slide sets.  相似文献   

16.

Background

Internal Jugular Veins (IJVs) are the principle outflow pathway for intracranial blood in clinostatism condition. In the seated position, IJVs collapse, while Vertebral Veins (VVs) increase the venous outflow and partially compensate the venous drainage. Spinal Epidural Veins are an additional drainage pathway in the seated position. Colour- Doppler-Sonography (CDS) examination is able to demonstrate IJVs and VVs outflow in different postural and respiratory conditions. The purpose of this study was to evaluate CDS quantification of the cerebral venous outflow (CVF) in healthy subjects and patients with multiple sclerosis (MS).

Methodology/Principal Findings

In a group of 27 healthy adults (13 females and 14 males; mean age 37.8±11.2 years), and 52 patients with MS (32 females and 20 males; mean age 42.6±12.1 years), CVF has been measured in clinostatism and in the seated position as the sum of the flow in IJVs and VVs. The difference between CVF in clinostatism and CVF in the seated position (ΔCVF) has been correlated with patients'' status (healthy or MS), and a number of clinical variables in MS patients. Statistical analysis was performed by Fisher''s exact test, non-parametric Mann-Whitney U test, ANOVA Kruskal-Wallis test, and correntropy coefficient.The value of ΔCVF was negative in 59.6% of patients with MS and positive in 96.3% of healthy subjects. Negative ΔCVF values were significantly associated with MS (p<0.0001). There was no significant correlation with clinical variables.

Conclusions/Significance

Negative ΔCVF has a hemodynamic significance, since it reflects an increased venous return in the seated position. This seems to be a pathologic condition. In MS patients, a vascular dysregulation resulting from involvement of the autonomous nervous system may be supposed. ΔCVF value should be included in the quantitative CDS evaluation of the cerebral venous drainage, in order to identify cerebral venous return abnormalities.  相似文献   

17.
Disseminated histoplasmosis is one the main AIDS-defining opportunistic infections in HIV-infected patients, notably in Latin America. The non-specific and proteiform clinical presentation leads to diagnostic delays that may lead to fatal outcomes. This retrospective multicentric study aimed to describe the frequency and manifestations of gastrointestinal histoplasmosis in French Guiana, and to compare patients with disseminated histoplasmosis with or without gastrointestinal involvement.Between January 1, 1981 and October 1, 2014 co-infections with HIV and histoplasmosis were enrolled. Inclusion criteria were: age >18 years, confirmed HIV infection; first proven episode of histoplasmosis.Among 349 cases of disseminated histoplasmosis, 245 (70%) had a gastrointestinal presentation. Half of patients with gastrointestinal signs had abdominal pain or diarrhea, mostly watery. Half of patients with abdominal pain had diarrhea (63/124) and half of those with diarrhea (63/123) had abdominal pain. A significant proportion of patients also had hepatomegaly and, to a lesser degree, splenomegaly. After adjusting for potential confounding, the presence of lymphadenopathies >2cm (AOR = 0.2, IC95 = 0.04–0.7, P = 0.01), Haitian origin (AOR = 0.04, IC95 = 0.004–0.4, P = 0.006) were associated with a lower prevalence of gastrointestinal signs and positive gastrointestinal presence of H. capsulatum. Persons with a gastrointestinal H. capsulatum were more likely to have a decreased prothrombin time, lower ferritin, lower liver enzymes, and lower concentrations of LDH than those without gastrointestinal signs and symptoms. They also had a shorter interval between symptoms onset and diagnosis. Patients with a positive gastrointestinal identification of H. capsulatum were less likely to die at 1 month than those without a gastrointestinal presentation (respectively, 4.6% vs 18.5%, P = 0.01).Subacute or chronic gastrointestinal presentations are very frequent during disseminated histoplasmosis, they seem less severe, and should lead to suspect the diagnosis in endemic areas. There were populational or geographic differences in the frequency of gastrointestinal manifestations that could not be explained.  相似文献   

18.
Tumor Necrosis Factor (TNF) was determined in the serum of 72 lung carcinoma patients. Twenty-four healthy subjects younger than 50 years and 10 healthy subjects older than 70 years were considered as control group. TNF was also measured in 20 patients with stage I sarcoidosis and in 15 patients with pulmonary fibrosis. The marker was detected in 32% of cases in the neoplastic group, in 37.5% of disease confined to the chest and in 25% of advanced disease cases. A large proportion of TNF-positive samples was found in sarcoidosis (30%), and even larger in pulmonary fibrosis (66.6%). TNF was also present in healthy subjects older than 70 (40%). We conclude that TNF is not specific of malignancy, being demonstrable in other benign pulmonary diseases and even in the course of physiological aging.  相似文献   

19.
The present article describes a comparative study of the performances of liposomes and ethosomes as specialized delivery systems for distamycin A (DA) and two of its derivatives. Liposomes and ethosomes were prepared by classical methods, extruded through polycarbonate filters, and characterized in terms of dimensions, morphology, and encapsulation efficiency. It was found that DA was associated with vesicles (either liposomes or ethosomes) by around 16.0%, while both derivatives of DA showed a percentage of association around 80% in the case of liposomes and around 50% in the case of ethosomes. In vitro antiproliferative activity experiments performed on cultured human and mouse leukemic cells demonstrated that vesicles were able to increase the activity of both derivatives of DA. In addition, it was demonstrated that the aging of both liposomes- and ethosomes-associated distamycin suspensions did not heavily influence the vesicle size, while all samples showed a relevant drug leakage with time. Moreover, according to the different physicochemical characteristics of DA and its derivatives (i.e., log P), vesicle-associated DA showed the highest loss of drug with respect to both its derivatives. In conclusion, the enhancement of drug activity expressed by these specialized delivery systems-associated DD could be interesting to obtain an efficient therapeutic effect aimed at reducing or minimizing toxic effects occurring with distamycins administration.  相似文献   

20.
Fish and mammalian metallothioneins: a comparative study   总被引:2,自引:0,他引:2  
Scudiero R  Temussi PA  Parisi E 《Gene》2005,345(1):21-26
Structural studies show that fish and mammalian metallothioneins are endowed of distinctive features. In particular, the ninth cysteine residue present in the alpha domain of fish metallothionein is shifted of two positions with respect to the mammalian metallothionein, introducing a conformational modification in the protein structure. In addition, the fish metallothionein is less hydrophobic and more flexible than its mammalian counterpart. Our previous studies showed that the hydropathy of piscine and mammalian metallothioneins is significantly correlated with organismal temperature. In the present paper we have performed phylogenetic comparative analysis on metallothioneins of 24 species of fish and mammals. The results of such analysis failed to indicate that metallothionein hydropathy is an adaptive response to the thermal regime of the species. We concluded that metallothionein hydropathy is a trait that did not evolve in association with environmental changes.  相似文献   

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