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1.
2.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
3.

Background

Most elderly trauma patients suffer blunt head injury and many utilize antithrombotic (AT) medications. The utility of delayed CT-head (D-CTH) in neurologically intact elderly patients using AT who have an intracranial hemorrhage (ICH) on presentation is unknown. We hypothesized that D-CTH would not alter clinical management and aimed to evaluate the role of D-CTH in this population.

Methods

A retrospective cohort study was performed. Patients ≥65 years sustaining blunt head injuries from January 2010 to July 2017 were identified using our level 1 trauma center database. AT-patients presenting with ICH who underwent D-CTH were included. Patients with worsened ICH were compared to those with stable to improved ICH on D-CTH. AT-patients were compared to a cohort of non-AT patients. Fisher’s Exact and Mann-Whitney U tests were utilized and a power analysis conducted.

Results

137?A?T and 34 non-AT patients were identified. There was no difference in hemorrhage progression or appearance of new ICH. No patient had a change in management from D-CTH in either cohort. AT-patients were slightly older (p?<?0.001), but cohorts were otherwise similar.50 AT-patients with worsened ICH were compared to 87 with stable ICH. There was no difference in cohort demographics. Hemorrhage progression did not vary with type of AT used but did increase if multiple types of synchronous ICH were present (p?<?0.001).

Conclusions

Our data supports abstaining from routine D-CTH of elderly ICH patients with an intact neurologic examination who are utilizing aspirin, clopidogrel or warfarin. Conclusions cannot be drawn regarding new oral anticoagulants (NOACs) given low enrollment. Further multicenter study is required to provide adequate power and detect small levels of management change.  相似文献   
4.
Objective: M-mode and 2D have been proposed for evaluating fetal myocardial thickness. However, studies comparing the performance of both modalities are lacking. We aimed to compare 2D versus M-mode reproducibility for assessing myocardial wall thicknesses.

Methods: A prospective study including 45 healthy fetuses from low-risk pregnancies evaluated between 18 and 41 weeks of gestation. Left and right ventricular free-wall and septal myocardial thicknesses were measured at end-diastole (ED) and end-systole (ES) in transverse 4-chamber view using 2D and M-mode. Intra- and interobserver reproducibility was evaluated by the concordance correlation coefficient (CCC). Both techniques were compared by t-test of the CCC.

Results: 2D and M-mode demonstrated excellent and similar intraobserver repeatability, with the best concordance in ES septal thickness (M-mode CCC 0.956 versus 2D-mode CCC 0.914). Interobserver reproducibility demonstrated also a high concordance, optimal in ES left ventricular free wall (M-mode 0.925 versus 2 D 0.855). Comparison of both techniques demonstrated a high concordance in all measurements, except for ED septal thickness with better reproducibility using M-mode (CCC 0.954 versus 0.847, p?=?.017).

Conclusions: 2D and M-mode can be used in a reproducible manner for measuring fetal myocardial thickness, with a slightly better performance of M-mode for assessing ED septal wall thickness.  相似文献   
5.
Writer's cramp is a task-specific dystonia that leads to involuntary hand postures during writing. Abnormalities of sensory processing may play a pathophysiological role in this disorder. Electrophysiology studies in a monkey model of focal dystonia have revealed de-differentiation of sensory maps and the existence of single cells in hand regions of area 3b with enlarged receptive fields that extend to the surfaces of more than one digit. These changes may lead to abnormal processing of simultaneous sensory inputs. To study abnormal processing of simultaneous sensory information in adult humans with writer's cramp, we used functional magnetic resonance imaging to compare the response in primary sensory cortex with simultaneous tactile stimulation of the index and middle finger, with the response to stimulation of each finger alone. We tested five patients with writer's cramp and seven unaffected (normal) subjects. In the normal subjects, a linear combination of the activation patterns for individual finger stimulation predicts the pattern of activity for combined stimulation with 12% error. In writer's cramp patients, the linear combination predicted the combined stimulation pattern with 30% error. Results indicate a nonlinear interaction between the sensory cortical response to individual finger stimulation in writer's cramp. This altered interaction may contribute to the motor abnormalities.  相似文献   
6.
A child had two to three generalized tonic-clonic (GTC) seizures per week unresponsive to phenobarbital (PB) and valproate (VPA). Interictal EEG demonstrated left occipital spikes. When carbamazepine (CBZ) therapy was started, he developed very frequent (4-6/day) complex partial seizures (CPS) characterized on ictal EEG by focal right temporal lobe discharges. The seizure exacerbation, which was associated with development of nonepileptic, multifocal myoclonus, resolved 24 h after CBZ was discontinued. The exacerbation occurred with therapeutic CBZ serum levels, but may have been related to the toxic levels of carbamazepine-10, 11-epoxide (CBZE).  相似文献   
7.
Various methods of cryopreservation of human endothelial cells (EC) were studied to determine their viability and behavior when seeded onto vascular prostheses made of polytetrafluoroethylene (PTFE). Three different protocols were used: (1) cyropreservation of whole umbilical vein, (2) cyropreservation of freshly extracted umbilical EC in suspension, and (3) cryopreservation of EC derived from a first subculture. Fresh EC and EC from a first subculture were used as controls. The viability and growth of these cells in culture media were studied, and basal prostacyclin levels were determined. The cells were assessed morphologically after they were seeded onto PTFE discs. Our results showed that the cryopreservation method that maintained the greatest viability was that in which previously cultured EC were used. Basal prostacyclin levels were significantly different following cyropreservation. However, when these cells were seeded onto PTFE discs their behavior was similar to that of fresh EC.We thank W. L. Gore & Associates for supplying the prostheses used in this study.Supported by a grant from the Comision Interministerial de Cieucia y Tecnologia SAF 92/0875.  相似文献   
8.
CONTEXT AND OBJECTIVE: The safety and efficacy of drug-eluting stents reduce the need for surgical revascularization. The objective of the present study was to investigate whether paclitaxel or rapamycin-eluting stent are effective in avoiding the need for coronary-artery bypass grafting. METHODS: This was a systematic review of the literature using the methodology of the Cochrane Collaboration. The type of study considered was controlled randomized trials; the type of intervention was drug-eluting or bare-metal stents; and the main outcome investigated was coronary-artery bypass grafting. RESULTS: The ten studies included in this systematic review did not show any statistically significant difference between the drug-eluting stents and the bare-metal stents with regard to the outcome of coronary-artery bypass grafting (confidence interval: 0.31 to 1.42). CONCLUSION: The surgical revascularization rate was not reduced by the use of drug-eluting stents.  相似文献   
9.
F. Daschner  H. Rüden 《Der Chirurg》1997,68(9):941-944
Zusammenfassung. Viele Hygienema?nahmen in Operationsabteilungen sind durch wissenschaftliche Untersuchungen nicht belegt. Die in dieser Arbeit vom Nationalen Referenzzentrum für Krankenhaushygiene, das 1996 vom Bundesgesundheitsministerium eingerichtet wurde, zusammengestellten Empfehlungen stützen sich auf die Ergebnisse wissenschaftlicher Untersuchungen und trennen so die unbedingt notwendigen von den weniger bzw. nicht sinnvollen Ma?nahmen.
Summary. Many hygienic procedures performed in operation units are not supported by scientific investigations. The following recommendations by the National Reference Center for Hospital Epidemiology, founded by the German Ministry of Health in 1996, are based on the scientific literature and separate necessary from less necessary and unnecessary procedures.
  相似文献   
10.
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