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31.
Percutaneous transluminal coronary angioplasty in octogenarians   总被引:1,自引:0,他引:1  
OBJECTIVE: To assess the safety and short- and long-term outcomes of percutaneous transluminal coronary angioplasty in octogenarians. DESIGN: Retrospective chart review of clinical series. SETTING: Referral-based university medical center. PATIENTS: Consecutive series of 54 octogenarian patients (mean age, 82.4 years) who had percutaneous transluminal coronary angioplasty between March 1980 and December 1988. Of these patients, 91% presented with severe angina (Canadian Cardiovascular Society Class III or IV); 59% had unstable angina. Twenty-six patients (48%) had had a previous myocardial infarction and 15 (28%) had had previous coronary artery bypass surgery. Multivessel disease was present in 44 patients (81%). Follow-up ranged from 1 to 50 months (mean, 19 months). INTERVENTION: Percutaneous transluminal coronary angioplasty. MEASUREMENTS and MAIN RESULTS: The angiographic success rate was 50 of 54 (93%; 95% CI, 81% to 98%) and the clinical success rate was 49 of 54 (91%; CI, 79% to 97%). Two patients had procedure-related myocardial infarction. Two patients died in the hospital, 1 from cardiac tamponade because of pacemaker perforation and 1 from cardiogenic shock after a myocardial infarction despite successful angioplasty. During the follow-up period 4 patients required bypass surgery, 2 had myocardial infarction, and 7 died (4 deaths were cardiac). Eleven patients (20%) had re-stenosis, 7 of whom were managed with repeat angioplasty, including 1 patient who had four procedures. At follow-up, 42 of 45 survivors (93%) were asymptomatic or had class II angina. The Kaplan-Meier survival for all patients, including those who died in the hospital, was 87% at 1 year and 80% at 3 years. Cumulative freedom from major cardiac events (death, myocardial infarction, or coronary bypass surgery) was 81% at 1 year and 78% at 3 years. CONCLUSIONS: Percutaneous transluminal coronary angioplasty can be done in octogenarians with a high rate of angiographic and clinical success, low complication rate, and a favorable long-term (3-year) outcome. As such, it is a treatment option in managing advanced coronary artery disease in this fragile group of patients.  相似文献   
32.
Consensus-derived structural determinants of the ankyrin repeat motif   总被引:13,自引:0,他引:13       下载免费PDF全文
The ankyrin repeat is one of the most common, modular, protein-protein interaction motifs in nature. To understand the structural determinants of this family of proteins and extract the consensus information that defines the architecture of this motif, we have designed a series of idealized ankyrin repeat proteins containing one, two, three, or four repeats by using statistical analysis of approximately 4,000 ankyrin repeat sequences from the PFAM database. Biophysical and x-ray crystallographic studies of the three and four repeat constructs (3ANK and 4ANK) to 1.26 and 1.5 A resolution, respectively, demonstrate that these proteins are well-folded, monomeric, display high thermostability, and adopt a very regular, tightly packed ankyrin repeat fold. Mapping the degree of amino acid conservation at each position on the 4ANK structure shows that most nonconserved residues are clustered on the surface of the molecule that has been designated as the binding site in naturally occurring ankyrin repeat proteins. Thus, the consensus amino acid sequence contains all information required to define the ankyrin repeat fold. Our results suggest that statistical analysis and the consensus sequence approach can be used as an effective method to design proteins with complex topologies. These generic ankyrin repeat proteins can serve as prototypes for dissecting the rules of molecular recognition mediated by ankyrin repeats and for engineering proteins with novel biological functions.  相似文献   
33.
Described in detail is the molecular epidemiology of wild-type 1 poliovirus circulation in Ghana between 1995-2008, following the implementation of a surveillance system for cases of acute flaccid paralysis and poliovirus infection. Molecular phylogenetic analysis combined with a detailed evaluation of epidemiological indicators revealed that the geographical and temporal circulation of wild-type poliovirus in Ghana was determined by the quality of the implementation of global eradication strategies. The transmission of "indigenous" wild-type 1 poliovirus was eliminated in 1999. However, a drastic reduction in national immunization campaigns resulted in the importation in 2003 and 2008 of wild-type 1 poliovirus from neighboring countries. Both outbreaks were promptly interrupted following resumption of immunization activities. The results detailed here provide scientific evidence that supports the feasibility of polio eradication in Central West Africa, one of the remaining endemic areas for the disease, provided that comprehensive immunization campaigns and sensitive surveillance systems are in place.  相似文献   
34.
Dietary supplements (DSs) are used extensively in the general population and many are promoted for the natural treatment and management of hypertension. Patients with hypertension often choose to use these products either in addition to or instead of pharmacologic antihypertensive agents. Because of the frequent use of DS, both consumers and health care providers should be aware of the considerable issues surrounding these products and factors influencing both efficacy and safety. In this review of the many DSs promoted for the management of hypertension, 4 products with evidence of possible benefits (coenzyme Q10, fish oil, garlic, vitamin C) and 4 that were consistently associated with increasing blood pressure were found (ephedra, Siberian ginseng, bitter orange, licorice). The goals and objectives of this review are to discuss the regulation of DS, evaluate the efficacy of particular DS in the treatment of hypertension, and highlight DS that may potentially increase blood pressure.  相似文献   
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37.

Background

The open abdomen is an increasingly used technique that is applied in a wide variety of clinical situations. The ABThera Open Abdomen Negative Pressure Therapy System is one of the most common and successful temporary closure systems, but it has limited ability to close the fascia in approximately 30% of patients. The abdominal reapproximation anchor system (ABRA) is a dynamic closure system that seems ideal to manage patients who may not achieve primary fascial closure with ABThera alone. We report on the use of the ABRA in conjunction with the ABThera in patients with an open abdomen.

Methods

We retrospectively analyzed patients with an open abdomen managed with the ABThera and ABRA between January 2007 and December 2012 at the Halifax Infirmary, QEII Health Science Centre, Halifax, Nova Scotia.

Results

Sixteen patients had combination therapy using the ABRA and ABThera systems for treatment of the open abdomen. After removing patients who died prior to closure, primary fascial closure was achieved in 12 of 13 patients (92%).

Conclusion

We observed a high rate of primary fascial closure in patients with an open abdomen managed with the ABThera system in conjuction with the ABRA. Applying mechanical traction in addition to the ABThera should be considered in patients predicted to be at high risk for failure to achieve primary fascial closure.  相似文献   
38.
Machine perfusion for preservation led to compelling success for the outcome of renal transplantation. Further refinements of methods to decrease preservation injury remain an issue of high interest. This study investigates functional and morphological aspects of kidneys preserved by subnormothermic (20 °C) machine perfusion (SNTM) compared with oxygenated hypothermic machine perfusion (HMPox) and cold storage (CS) in a donation after circulatory death (DCD) model. After 30 min of warm ischaemia, porcine kidneys were randomly assigned to preservation for 7 h by CS, HMPox or SNTM. Afterwards, kidneys were reperfused for 2 h with autologous blood in vitro for assessment of function and integrity. Application of SNTM for preservation led to significantly higher blood flow and urine output compared with both other groups. SNTM led to a twofold increased creatinine clearance compared with HMPox and 10‐fold increased creatinine clearance compared with CS. Structural integrity was best preserved by SNTM. In conclusion, this is the first study on SNTM for kidneys from DCD donors. SNTM seems to be a promising preservation method with the potential to improve functional parameters of kidneys during reperfusion.  相似文献   
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40.
Bla g 4 is a male cockroach specific protein and is one of the major allergens produced by Blattella germanica (German cockroach). This protein belongs to the lipocalin family that comprises a set of proteins that characteristically bind small hydrophobic molecules and play a role in a number of processes such as: retinoid and pheromone transport, prostaglandin synthesis and mammalian immune response. Using NMR and isothermal titration calorimetry we demonstrated that Bla g 4 binds tyramine and octopamine in solution. In addition, crystal structure analysis of the complex revealed details of tyramine binding. As tyramine and octopamine play important roles in invertebrates, and are counterparts to vertebrate adrenergic transmitters, we speculate that these molecules are physiological ligands for Bla g 4. The nature of binding these ligands to Bla g 4 sheds light on the possible biological function of the protein. In addition, we performed a large-scale analysis of Bla g 4 and Per a 4 (an allergen from American cockroach) homologs to get insights into the function of these proteins. This analysis together with a structural comparison of Blag 4 and Per a 4 suggests that these proteins may play different roles and most likely bind different ligands.  相似文献   
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