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81.
Two novel catechol 1,2-dioxygenase (C 1,2-O) genes have been isolated from an Acinetobacter radioresistens strain that grows on phenol or benzoate as sole carbon and energy source. Designated as catA(A) and catA(B), they encode proteins composed of 314 and 306 amino acids, whose deduced sequences indicate that they have approximately 53% identity, whereas their NH2-terminal and COOH-terminal regions have no sequences in common. This may explain their different thermal and pH stability. Polyclonal antibodies raised against an amino-terminal CatA(A) peptide or the whole CatA(B) protein were used to establish their inducible and differential expression patterns upon bacterial growth in phenol or benzoate. The CatA(A) protein (IsoA) was induced by both phenol and benzoate though with different kinetics, whereas the catA(B) product (IsoB) was constitutively produced at low levels that increased only during growth in the presence of benzoate.  相似文献   
82.

Objectives

The present study aimed to investigate any associations between parameters of body fat mass distribution and levels of serum uric acid (sUA), a well-documented cardiovascular risk factor, among non-obese women ranging from pre- to post-menopausal status.

Methods

In this cross-sectional population-based study we assessed body fat distribution by dual-energy-X-ray absorptiometry (DXA), and sUA levels in 101 pre- and 134 post-menopausal non-obese apparently healthy women.

Results

Multivariate stepwise regression analysis revealed that sUA was independently associated to the indicators of overall fatness, i.e. body mass index (β = 0.339, p < 0.001) and DXA-assessed total and percentage body fat (β = 0.366, p < 0.001 and β = 0.412, p < 0.001, respectively), only among post-menopausal women. Within this sample subset, trunk (i.e. central) fat mass emerged as a strong predictor of sUA (β = 0.408, p < 0.001), after taking the potential confounders (including body mass index) into account.

Conclusion

Central fat accumulation was found to be independently associated with higher sUA levels among non-obese women in post- but not among those in pre-menopause.  相似文献   
83.
Cell-surface high-affinity monomeric 67-kD laminin receptors have been proposed to promote the invasion and metastasis of a variety of tumours, but there are, as yet, no data regarding the expression of these molecules in pancreatic endocrine tumours (PETs). The prognosis of these very rare tumours is problematic and the only irrefutable evidence of their malignancy still continues to be the occurrence of local invasion and metastases. In this retrospective investigation, 34 functioning and 48 non-functioning sporadic PETs were evaluated for the expression of the MLuC5 monoclonal antibody, which specifically recognizes the 67-kD laminin receptors. Laminin receptors were found in 42/82 cases (51 per cent) and their expression was associated with metastatic disease (P<0·001), high proliferative activity expressed by a Ki-67 index above 5·0 per cent (P<0·001), absence of progesterone receptors (P=0·013), immunoreactivity for hormones other than insulin (P<0·001), a tumour diameter more than 3·0 cm (P=0·001), and a fatal clinical outcome (P<0·001). Laminin receptors were also expressed by most metastatic foci and all intravascular emboli of tumour cells. Positivity for laminin receptors was associated with shorter survival in functioning (P=0·026) and non-functioning (P=0·042) tumours, as well as in the whole series of pancreatic endocrine tumours (P<0·001). On multivariate analysis, laminin receptor expression was not an independent prognostic factor, while a Ki-67 index above 5·0 per cent was the most powerful predictor of survival. However, the association of laminin receptor expression and Ki-67 index could identify a group of malignant PETs with low proliferative activity characterized by an intermediate prognosis. In conclusion, these data suggest that monomeric laminin receptors may play a role in the invasion and metastasis of PETs and that their expression may be an additional prognostic factor, along with proliferative activity. © 1997 by John Wiley & Sons, Ltd.  相似文献   
84.
BACKGROUND: To examine the emotional and behavioral characteristics of the offspring of depressed parents with and without anger attacks. METHODS: Forty-three parents who met criteria for major depressive disorder (MDD) completed the Achenbach Child Behavior Checklist - Parent Report Version (CBCL) for each of their birth children (n = 58, age range 6-17 years). Unpaired t tests were used to evaluate the CBCL scale score differences between children of parents with and children of parents without anger attacks. Baseline demographics and clinical differences between the two groups of parents were also evaluated. RESULTS: Parents with anger attacks had a significantly younger age of onset of MDD. Offspring of depressed parents with anger attacks were found to have significantly lower social and school competency scale scores and higher scores for delinquency, attention problems, and aggressive behavior. In addition, this group was found to have a significantly higher total T score (a global measure of psychopathology). CONCLUSIONS: There are some important differences between offspring of depressed parents with and without anger attacks. This finding may be important in identifying and formulating intervention strategies for childhood problems in the offspring of depressed parents.  相似文献   
85.

Introduction

Several neurodegenerative brain proteinopathies, including Alzheimer's disease (AD), are associated with cerebral deposition of insoluble aggregates of α-synuclein. Previous studies reported a trend toward increased cerebrospinal fluid (CSF) α-synuclein (α-syn) concentrations in AD compared with other neurodegenerative diseases and healthy controls.

Methods

The pathophysiological role of CSF α-syn in asymptomatic subjects at risk of AD has not been explored. We performed a large-scale cross-sectional observational monocentric study of preclinical individuals at risk for AD (INSIGHT-preAD).

Results

We found a positive association between CSF α-syn concentrations and brain β-amyloid deposition measures as mean cortical standard uptake value ratios. We demonstrate positive correlations between CSF α-syn and both CSF t-tau and p-tau181 concentrations.

Discussion

Animal models presented evidence, indicating that α-syn may synergistically and directly induce fibrillization of both tau and β-amyloid. Our data indicate an association of CSF α-syn with AD-related pathophysiological mechanisms, during the preclinical phase of the disease.  相似文献   
86.
Amyotrophic Lateral Sclerosis (ALS) is a devastating incurable disease. Stem-cell-based therapies represent a new possible strategy for ALS clinical research. The objectives of this Phase 1 clinical study were to assess the feasibility and toxicity of mesenchymal stem cell transplantation and to test the impact of a cell therapy in ALS patients. The trial was approved and monitored by the National Institute of Health and by the Ethics Committees of all participating Institutions. Autologous MSCs were isolated from bone marrow, expanded in vitro and analyzed according to GMP conditions. Expanded MSCs were suspended in the autologous cerebrospinal fluid (CSF) and directly transplanted into the spinal cord at a high thoracic level with a surgical procedure. Ten ALS patients were enrolled and regularly monitored before and after transplantation by clinical, psychological, neuroradiological and neurophysiological assessments. There was no immediate or delayed transplant-related toxicity. Clinical, laboratory, and radiographic evaluations of the patients showed no serious transplant-related adverse events. Magnetic resonance images (MRI) showed no structural changes (including tumor formation) in either the brain or the spinal cord. However the lack of post mortem material prevents any definitive conclusion about the vitality of the MSCs after transplantation. In conclusion, this study confirms that MSC transplantation into the spinal cord of ALS patients is safe and that MSCs might have a clinical use for future ALS cell based clinical trials.  相似文献   
87.

Background

Low-Field Magnetic Stimulation (LFMS) is a novel, non-invasive, sub-threshold neuromodulation technique, shown in preliminary studies to have immediate mood elevating effects in both unipolar and bipolar depressed patients.

Objective

We aimed to assess the antidepressant augmentation effects at 48 h of LFMS administered on two consecutive days compared to sham treatment in treatment resistant depression (TRD) subjects, using the Sequential Parallel Comparison Design (SPCD).

Methods

Eighty-four eligible subjects with TRD were randomly assigned to double-blind treatment with LFMS 20 min/day for four days, sham treatment 20 min/day for four days, or sham treatment 20 min/day for 2 days followed by LFMS treatment 20 min/day for two days, using the pre-randomization version of the SPCD (randomization 1:1:1). The SPCD analyses used a repeated measures linear modeling approach with maximum likelihood estimation to use all available data, and using a 60–40 weighting of Stage 1 vs. 2 responses, with the primary outcome being measured after 2 and 4 days.

Results

Both primary and secondary outcome measures consistently showed no differences between LFMS-treated patients and those treated with sham, with the exception of a slight, non-significantly greater improvement than sham in the visual analogue scale (VAS) sad mood on LFMS-treated patients. LFMS treatment was relatively well tolerated.

Conclusions

We did not observe a significantly greater, rapid efficacy of LFMS compared to sham therapy. Future studies need to examine the possible therapeutic effects of more intensive forms of LFMS, as other forms of neurostimulation typically require longer duration of exposure.  相似文献   
88.
89.
The present study examined whether Snoezelen and Stimulus Preference environments have differential effects on disruptive and pro-social behaviors in adults with profound mental retardation and autism. In N = 27 adults these target behaviors were recorded for a total of 20 sessions using both multi-sensory rooms. Three comparison groups were created by diagnosis and motor respective linguistic abilities. Each client was exposed to only one multi-sensory room. Results showed that Snoezelen intervention decreased disruptive behaviors only in individuals with autism, while Stimulus Preference increased pro-social behaviors only in participants with profound mental retardation with co-occurring poor motor and linguistic abilities.Furthermore, several trend analyses of the improved behaviors were conducted throughout all sessions toward short and mid term effects of the multi-sensory room applications.These findings support both the prudence of using the Snoezelen room in individuals with developmental disabilities and the importance of using a Stimulus Preference assessment in multi-sensory environments in clients with profound mental retardation.  相似文献   
90.
PURPOSE: Lung cancer has a high mortality rate and its prognosis largely depends on early detection. We report the prevalence data of the study on early detection of lung cancer with low-dose spiral CT underway at our hospital. MATERIALS AND METHODS: Since the beginning of 2001, 519 asymptomatic volunteers have undergone annual blood tests, sputum tests, urinalyses and low-dose spiral CT. The inclusion criteria were age (=/> 55 years old), a history of cigarette smoking and a negative history for previous neoplastic disease. The diagnostic workup varied depending on the size and CT features of the nodules detected. RESULTS: At baseline, the CT scan detected nodules > 5 mm in 22% of subjects; the nodules were single in 42 and multiple in 71. In 53% of cases the findings were completely negative, while in 122 (23.4%) nodules with a diameter < 5 mm were detected. Six cases of lung cancer were identified, of which four were stage I, one stage was IIIB and one was stage IV with adrenal metastases. CONCLUSIONS: Our preliminary data on spiral CT as a potential new diagnostic tool for lung cancer screening, although less promising than the Japanese and ELCAP results, confirm the feasibility of the technique. Additional validation is, however, required.  相似文献   
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