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1.
To determine whether pulsatile hypothermic perfusion with University of Wisconsin preservation solution is superior to topical cooling as a method for the preservation of amputated limbs, six pairs of amputated canine limbs were preserved for twelve to fifteen hours. One limb of each pair was subjected to topical cooling and the other, to pulsatile hypothermic perfusion with University of Wisconsin solution. The bioenergetic status of the limbs was monitored by 31phosphorus magnetic-resonance spectroscopy, and histological evaluation was performed to assess ischemic changes in the preserved tissue. The pH and tissue levels of adenosine triphosphate declined three times more slowly in the limbs that were preserved by pulsatile hypothermic perfusion than in the topically cooled limbs. Consistent with these findings, the perfused limbs also had less histological evidence of ischemic injury. The data from this in vitro study show that pulsatile hypothermic perfusion with University of Wisconsin solution, in combination with an optimum degree of topical cooling, is superior to topical cooling alone as a method of preserving the bioenergetic status of amputated limbs.  相似文献   
2.
We report a case of mucous gland adenoma arising in the left main bronchus which was initially misdiagnosed as asthma and review the previous reported cases of this rare tumor published in the available literature.  相似文献   
3.
In a recent study we described an increase of elastic tissue fibres in blood vessel walls of placental stem villi during pre-eclampsia when compared to uncomplicated pregnancies. Furthermore, the thickness of these blood vessel walls was enhanced in pre-eclampsia. Since it is known that elastic tissue fibres increase in systemic hypertension, it may be assumed that the enhancement of elastic tissue fibres in placental stem villi during pre-eclampsia may be induced by the hypertension. To get further insight into this assumption, we examined the amount of elastic tissue fibres in stem villus blood vessels of placentae of pregnancies complicated by intrauterine growth retardation (isolated IUGR, fourteen cases), a disease without hypertension of the mother and such with pre-eclampsia and concomitant IUGR (IUGR+PE, nine cases). Each study group was compared with uncomplicated pregnancies (twenty-six cases). Unfixed cryostat serial sections were processed for conventional orcein staining and for the demonstration of alpha-actin-immunoreactivity. The intensity of orcein staining of stem villus blood vessel walls was evaluated by a semiquantitative score method. Significant lower intensities of orcein staining were calculated for blood vessel walls of placentae of isolated IUGR (P=0.0007) and IUGR+PE (P=0.0039) when compared to uncomplicated pregnancies each. Additionally, the blood vessel wall thickness of stem villi of isolated IUGR (P=0.0081) and IUGR+PE (P=0.0007) was significantly reduced. In comparison to the above mentioned investigation, our results show that, in contrast to isolated pre-eclampsia, elastic tissue fibres are decreased during pregnancies complicated by IUGR, independently of the occurrence of concomitant pre-eclampsia when compared to uncomplicated pregnancies. From our studies it may be considered that the increase of elastic tissue fibres in placentae of patients with isolated pre-eclampsia may be induced by systemic hypertension. Furthermore, our study underline arguments that IUGR may be an independent disease of the fetus.  相似文献   
4.
Flexible tantalum stents: Effects in the stenotic canine urethra   总被引:2,自引:0,他引:2  
Purpose Evaluate the effects of flexible tantalum stents (Strecker) implanted into stenotic canine urethras.Methods Eight conditioned, adult, German shepherd dogs, weighing 30–40 kg, were used. Strictures were created surgically in the bulbar urethra just proximal to the os penis. Two months postsurgery, strictures were documented radiographically and then balloon dilated. Following dilatation, a single Strecker stent was placed across the stricture. Stents were 7 mm in expanded diameter and either 2 or 4 cm in length. Retrograde urethrography was performed immediately after stent placement and then biweekly for up to 12 months. Two dogs were sacrificed at 2, 4, 6, and 12 months post-stenting, and necropsy was performed. The urethra was excised, fixed, and examined by scanning electron and light microscopy.Results Clinical success was achieved without complications in all animals. Hyperplasia of the urothelium was noted 4–6 weeks after stent placement and was most pronounced at 4–6 months. Mucosal folds were found between the stent struts. Restenosis occurred at the distal end of the stent in one dog. Histological alterations were noted in the deeper layers of the urethral wall.Conclusion Strecker stents were well tolerated in all animals and seem useful for the treatment of urethral strictures.Presented at CIRSE Annual Meeting and Postgraduate Course, Budapest, June 20–24, 1993  相似文献   
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PURPOSE: To determine the effect of taxane-based chemotherapy on intratumoral levels of cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) in patients with non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Lung specimens obtained at the time of surgery were used to measure levels of COX-2 and PGE(2) in tumors and adjacent nontumorous tissues in three subsets of NSCLC patients who underwent: (A) surgical resection only (n = 16); (B) surgical resection after preoperative taxane-based chemotherapy (n = 13); or (C) surgical resection after preoperative chemotherapy coadministered with the selective COX-2 inhibitor, celecoxib 400 mg bid (n = 17). RESULTS: Levels of intratumoral PGE(2) were nearly 3-fold higher among patients who received preoperative chemotherapy compared with those treated by surgery alone (P < 0.001). This difference was abrogated by the addition of celecoxib to preoperative chemotherapy (P < 0.001). Amounts of intratumoral COX-2 were approximately 3-fold higher in groups of patients who received preoperative chemotherapy with celecoxib (P < 0.0001) or without celecoxib (P < 0.001), compared with the group who underwent surgical resection only. Importantly, statistically significant positive correlations between COX-2 and PGE(2) were observed in the surgery only (r = 0.502, P = 0.047) and preoperative chemotherapy groups (r = 0.740, P = 0.004); this correlation was abrogated when celecoxib was given with chemotherapy (r = 0.005, P = 0.98). CONCLUSIONS: Treatment with chemotherapy led to increased amounts of COX-2 and PGE(2) in NSCLC. Cotreatment with celecoxib abrogated the increase in levels of PGE(2) but not COX-2 induced by chemotherapy. Importantly, these results clearly show that levels of a pharmacologic target (i.e., COX-2) can be affected by both the intrinsic molecular properties of a tumor and therapy.  相似文献   
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The role of autophagy, a process in which the cell self-digests its own components, was investigated in glioma cell death induced by the hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase-inhibiting drug simvastatin. Induction of autophagy and activation of autophagy-regulating signalling pathways were analyzed by immunoblotting. Flow cytometry/fluorescent microscopy was used to assess autophagy-associated intracellular acidification and apoptotic markers (phosphatidylserine exposure, DNA fragmentation and caspase activation). Cell viability was determined by crystal violet, MTT or LDH release assay. Simvastatin treatment of U251 and C6 glioma cell lines caused the appearance of autophagolysosome-like intracytoplasmic acidic vesicles. The induction of autophagy in U251 cells was confirmed by the upregulation of autophagosome-associated LC3-II and pro-autophagic beclin-1, as well as by the downregulation of the selective autophagic target p62. Simvastatin induced the activation of AMP-activated protein kinase (AMPK) and its target Raptor, while simultaneously downregulating activation of Akt. Mammalian target of rapamycin (mTOR), a major AMPK/Akt downstream target and a major negative autophagy regulator, and its substrate p70 S6 kinase 1 were also inhibited by simvastatin. Mevalonate, the product of HMG-CoA reductase enzymatic activity, AMPK siRNA or pharmacological inactivation of AMPK with compound C suppressed, while the inhibitors of Akt (10-DEBC hydrochloride) and mTOR (rapamycin) mimicked autophagy induction by simvastatin. Inhibition of autophagy with bafilomycin A1, 3-methyladenine and LC3β shRNA, as well as AMPK inhibition with compound C or AMPK siRNA, markedly increased apoptotic death of simvastatin-treated U251 cells. These data suggest that inhibition of AMPK-dependent autophagic response might sensitize glioma cells to statin-induced apoptotic death.  相似文献   
9.
This paper deals with the selection of the optimal material for railway wagons, from among three different steel and three aluminium based materials, by using four different Multicriteria Decision Making Methods (MCDM) and comparing their ranking of the materials. We analysed: Dual-Phase 600 steel, Transformation-Induced Plasticity (TRIP) 700 steel, Twinning-Induced Plasticity (TWIP) steel, Aluminium (Al) alloys, Al 6005-T6, and Al 6082-T6, and porous Al structure with closed cells. Four different MCDM methods were used: VIKOR, TOPSIS, PROMETTHEE and the Weighted aggregated sum product assessment method (WASPAS). Key material properties that were used in the MCDM analysis were: density, yield strength (Y.S.), tensile strength (T.S.), Y.S./T.S. ratio, Youngs modulus (Y.M.), cost and corrosion resistance (C.R.). Research results indicate that aluminium and its alloys prove to be the most suitable material, based on setup criteria. Advanced steels also achieved good ranking, making them a valid option, immediately behind lightweight aluminium alloys. Porous aluminium did not perform well, according to the used MDCM methods, mainly due to the significantly lower strength exhibited by the porous structures in general.  相似文献   
10.
AimTo assess the prevalence of actionable pharmacogenetic interventions in patients who underwent pharmacogenetic testing with a multi-gene panel.MethodsWe retrospectively reviewed single-center electronic health records. A total of 319 patients were enrolled who underwent pharmacogenomic testing with the RightMed test panel using TaqMan quantitative real-time PCR method and copy number variation analysis to determine the SNPs in the 27 target genes.ResultsActionable drug-gene pairs were found in 235 (73.7%) patients. Relevant guidelines on genotype-based prescribing were available for 133 (56.7%) patients at the time of testing. Based on the patients’ genotype, 139 (43.6%) patients were using at least one drug with significant pharmacogenetic interactions.ConclusionTwo out of three patients had at least one drug-gene pair in their therapy. Further studies should assess the clinical effectiveness of integrating pharmacogenomic data into patients’ electronic health records.

The field of pharmacogenetics has been booming in the past decades, with research being focused on studying novel genetic variants that impact drug metabolism or pharmacological effect, which ultimately affects the patient’s response to a given dose of medication. Pharmacogenetics examines gene-drug interactions that change pharmacokinetic and/or pharmacodynamic properties of a drug (1). It is impossible to implement any of the principles of personalized medicine without determining the patients'' pharmacogenetic profile before starting a new therapy (2).Several professional organizations, namely, Clinical Pharmacogenetics Implementation Consortium (CPIC) and Dutch Pharmacogenetics Working Group (DPWG), provide comprehensive and understandable guidelines on genotype-based drug prescribing (3,4). Pharmacogenomic prescribing guidelines are growing in number and are available for various drug classes including the cardiovascular drugs, drugs affecting the central nervous system, gastrointestinal drugs, drugs that treat infectious and malignant diseases, immunosuppressives, analgesics, and other (5,6).Several companies specialize in pharmacogenetic panels, making it easily accessible for patients and clinicians of various specialties to obtain the test results in a matter of days or weeks. These commercial tests are developed by industry stakeholders and can be implemented in various settings during the diagnostic or treatment process (7,8). They are comprehensive and include a number of genes that are important for the pharmacologic profile across drug groups, or targeted for a certain category of drugs, ie, psychiatric, analgesics, oncologic drugs, etc. Data on the rate of utilization and clinical utility of such tests are lacking. A recent study found that from 2013 until 2017 only 5712 insured US patients performed pharmacogenetic testing of at least one gene (9). The field of pharmacogenomics is still in its early stages. One of the principal problems is the education of health care providers responsible for ordering and interpreting the test results. In a recent survey, 84.3% of doctors from seven European countries deemed pharmacogenomics relevant for their practice, however 65.7% did not order a pharmacogenomic test in the last year (10). Potential implementation of pharmacogenomics in the clinical practice should be complemented with a clinical decision support tool integrated into the patient’s electronic health record (11,12). In Croatia, pharmacogenomic testing has been available for over a decade, with multiple studies examining population genetics and cost-effectiveness of pharmacogenomic guided therapies (13,14). However, commercial panel-based tests targeting multiple genes known to influence drug response is a new concept that was implemented in 2018 at St. Catherine Hospital in Zagreb (8,15,16).The aim of this retrospective study was to assess the proportion of patients with actionable pharmacogenetic interventions in a single center from 2018 to 2021 who had undergone pharmacogenetic testing of 27 genes by using a commercial gene panel.  相似文献   
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