Fatal cerebellar stroke following emergency endovascular stent grafting of a leaking thoracic aortic aneurysm: A case report

Stent-grafting of thoracic aortic diseases has developed as an alternative therapeutic modality in thoracic aneurysm management. Postprocedural complications include mortality, endoleaks, paraplegia and stroke. Other complications that may arise in cases of overstenting the origin of the left subclavian arther include left upper limb ischemia, subclavian steal syndrome and stroke. Posterior circulation strokes due to vertebral artery insufficiency have been reported in the past. In the present case, a fatal stroke caused by a cerebellar infarct culminating in the death of a patient with a leaking thoracic aortic aneurysm is reported. Medical personnel as well as patients should be aware of this possible complication. Vigilance in assessing the contralateral cerebral circulation before the procedure is a prerequisite in less acute circumstances.

Comparison of the relative analgesic efficacies of epidural or intramuscular diamorphine following total knee arthroplasty

BACKGROUND AND OBJECTIVES

Debate has proliferated as to the true site of action of opioids when placed in the epidural space. The aim of this study was to compare the analgesic effects of a bolus of diamorphine given by the epidural or intramuscular route.

METHODS

Sixty patients having elective primary total knee replacements were recruited and randomized to receive epidural or intramuscular diamorphine. A lumbar epidural catheter was sited and 10 mL of bupivacaine 0.5% wt vol-1 was injected. Patients subsequently received diamorphine 5 mg into the epidural space or as an intramuscular injection. Patient-controlled analgesia with intravenous morphine was used for postoperative analgesia. The primary outcome measures included time to first patient-controlled analgesia use and total morphine consumption in 24 h. Secondary end-points considered possible treatment complications.

RESULTS

All primary end-points showed significant differences in favour of epidural diamorphine. Medians for times to first patient-controlled analgesia use and total 24 h morphine requirements were significantly different (P < 0.001) at 418 vs. 198 min and 11 vs. 39 mg, respectively. There were no significant differences in secondary end-points.

CONCLUSIONS

This study has shown the superior analgesic efficacy of epidural diamorphine when compared to intramuscular injection.

Programmed −1 ribosomal frameshifting in the SARS coronavirus

Programmed −1 ribosomal frameshifting is an alternate mechanism of translation used by coronavirus to synthesize replication proteins encoded by two overlapping open reading frames. For some coronaviruses, the mRNA cis-acting stimulatory structures involved in this process have been characterized, but their precise contribution to ribosomal frameshifting is not completely understood. Recently, a novel coronavirus was identified as the causative agent of the severe acute respiratory syndrome. This review describes the mRNA motifs involved in programmed −1 ribosomal frameshifting in this virus.

Paget's disease in New Zealand: evidence for declining prevalence

The prevalence rate of Paget's disease in New Zealand is believed to be among the highest in the world, but recent data suggest that it may have decreased in recent decades. We estimated the current prevalence of Paget's disease in subjects of European origin (>55 years of age) in two New Zealand cities (Dunedin and Auckland) based on review of nearly 2000 pelvic radiographs. Prevalence rate increased with age (p = 0.022) and was higher in men (p = 0.014), but there was no significant difference between the two cities. The Dunedin data were compared with a 1983 survey from the same city, and prevalence was approximately half its previous level (p = 0.012). In Auckland, the prevalence of an isolated raised plasma alkaline phosphatase level (>150 U/L, normal range <120 U/L) was estimated in over 80,000 blood samples processed at a community laboratory. The prevalence of "biochemical Paget's disease," as assessed by this surrogate marker, was very similar to that observed in the radiographic survey in Auckland for subjects <80 years of age, but not for older subjects. We conclude that the prevalence of Paget's disease in New Zealand has declined over the past two decades, indicating that there are important environmental determinants in its development. Biochemical estimates of the prevalence of Paget's disease agree well with radiographic estimates, except in the elderly. The method used herein offers an alternative way of determining the prevalence of Paget's disease.

Modified Norwood operation for hypoplastic left heart syndrome

BACKGROUND

We examined early results in infants with hypoplastic left heart syndrome undergoing the Norwood operation with perioperative use of inhaled nitric oxide and application of extracorporeal membrane oxygenation.

METHODS

Medical records were reviewed retrospectively.

RESULTS

Between April 1997 and March 2001, 50 infants underwent a modified Norwood operation for hypoplastic left heart syndrome. Mean age at operation was 7.5 +/- 5.7 days, and mean weight was 3.1 +/- 0.5 kg. Five infants had a delayed operation because of sepsis. The mean diameter of the ascending aorta by echocardiography was 3.6 +/- 1.8 mm. Ductal cannulation was used to establish cardiopulmonary bypass in all patients. Mean circulatory arrest time was 39.4 +/- 4.8 minutes. The size of the pulmonary-systemic shunt was 3.0 mm in 6 infants, 3.5 mm in 37, and 4.0 mm in 7. Infants with persistent hypoxia (partial pressure of oxygen < 30 mm Hg) received nitric oxide after they were weaned from cardiopulmonary bypass. Extracorporeal membrane oxygenation was initiated in 8 infants in the pediatric intensive care unit primarily for low cardiac output and in 8 in the operating room because of the inability to separate them from cardiopulmonary bypass. The 30-day mortality rate was 22% (11 of 50 patients), and the hospital mortality rate was 32% (16 of 50 patients). Mean follow-up was 17 months. Ten patients (20%) underwent stage-two repair, with one operative death. One survivor had a Fontan procedure, and 2 underwent heart transplantation, with one death.

CONCLUSIONS

Early application of extracorporeal membrane oxygenation for hemodynamic instability and selective use of nitric oxide for persistent hypoxia in the immediate postoperative period may improve survival of patients with hypoplastic left heart syndrome. Renal failure requiring hemofiltration during extracorporeal membrane oxygenation (p < 0.05) and cardiopulmonary arrest in the pediatric intensive care unit (p < 0.05) were predictors of hospital mortality.

True aneurysm of a femoropopliteal vein graft

Aneurysmal dilatation of saphenous vein grafts mostly represent thin-walled pseudoaneurysms at anastomotic sites. True aneurysmal dilatation of femoropopliteal bypass vein grafts is rare. We report this unusual case, which was repaired with a prosthetic graft.

Long-term results of local recurrence after breast conservation treatment for invasive breast cancer

PURPOSE

The outcome for women with a local failure after breast conservation treatment is not well described in the literature. Because local recurrence is a potentially salvageable event, this study was performed to evaluate the outcome of patients with local recurrence after breast conservation surgery and definitive radiation treatment.

METHODS AND MATERIALS

The study population consisted of 112 patients with ipsilateral breast tumor recurrence. There were 100 isolated local recurrences and 12 local-plus-regional recurrences. There were 93 invasive local recurrences and 19 DCIS (ductal carcinoma in situ) local recurrences. Local recurrences were detected by physical examination alone in 42 patients, mammography alone in 47 patients, and both modalities in 23 patients. All patients were initially treated with breast conservation treatment with or without systemic therapy and subsequently treated at the time of local recurrence with salvage mastectomy with or without systemic therapy. The mean and median follow-up times after local recurrence were 49 and 44 months, respectively.

RESULTS

For the entire group of 112 patients, the overall survival at 10 years after local recurrence was 69%, the cause-specific survival was 71%, and the freedom from distant metastases was 47%. For the 93 patients with an invasive local recurrence, the overall survival at 10 years was 64%, cause-specific survival was 67%, and freedom from distant metastases was 44%. For the 93 patients with an invasive local recurrence, interval from diagnosis to local recurrence (< or =2 years vs. 2.1-5 years vs. >5 years) predicted for overall survival at 5 years (65% vs. 84% vs. 89%; p = 0.03). Method of detection of local recurrence (physical examination vs. mammography vs. both methods) also predicted for 5-year overall survival (73% vs. 91% vs. 93%, respectively; p = 0.04). On multivariable analysis, interval from diagnosis to local recurrence was an independent predictor of overall survival (p = 0.03). Method of detection of local recurrence (physical examination vs. mammography vs. both methods) was borderline in predicting for 5-year cause-specific survival (73% vs. 91% vs. 93%, respectively; p = 0.06). Similarly, interval from diagnosis to local recurrence (< or =2 years vs. 2.1-5 years vs. >5 years) was a borderline predictor of 5-year cause-specific survival (65% vs. 84% vs. 89%; p = 0.08). No factors that predicted for freedom from distant metastases were identified. There were three second locoregional failures on the chest wall. Two of the 19 patients with a DCIS local recurrence have died of metastatic breast cancer. Death was probably not related to their local recurrence, but rather a result of persistent risk from an invasive primary cancer.

CONCLUSIONS

This analysis provides long-term data after salvage treatment for patients who experience local recurrence after breast conservation treatment. The variables of method of detection and interval from diagnosis to local recurrence are identified as having prognostic significance for overall and cause-specific survival. In view of the potential for long-term survival, aggressive attempt at salvage treatment is warranted for the patient with local recurrence after breast conservation treatment. Second local recurrence after salvage mastectomy is an uncommon event. Although DCIS local recurrences may not in themselves cause an increase in the risk of mortality, the risk from the primary invasive cancer persists.

Brachytherapy for head and neck cancer: a case study

Brachytherapy currently is being used as a treatment modality for head and neck cancer. A case study is presented to illustrate the treatment and safety procedures required when brachytherapy is delivered. A multidisciplinary approach is essential to ensure that family and staff exposure to radiation is minimized. Nursing care considerations include preventing airway impairment, maintaining hydration, developing alternative communication methods, pain management, and bowel preparation. Through intensive patient, family, and staff education, patients with head and neck cancer can be treated with brachytherapy safely and effectively.

Transesophageal echocardiography in pediatric congenital heart disease

The uses of transesophageal echocardiography have expanded dramatically over the last decade. With advances in technology, this imaging modality has become readily available for evaluation of the complex pediatric population with congenital heart disease. This article discusses the many uses of transesophageal echocardiography in this population, in the outpatient setting, in the peri-operative period, and in the cardiac catheterization laboratory.

Co-occurrence of abuse of different drugs in men: the role of drug-specific and shared vulnerabilities

BACKGROUND

Previous research has demonstrated genetic and environmental influences on abuse of individual substances, but there is less known about how these factors may influence the co-occurrence of abuse of different illicit drugs.

METHODS

We studied 3372 male twin pairs from the Vietnam Era Twin Registry. They were interviewed using the Diagnostic Interview Schedule, Version III, Revised to investigate the extent to which the abuse of different categories of drugs occurs together within an individual, as well as the possibility that genetic and environmental factors are responsible for observed co-occurrence. Co-occurrence was quantified using odds ratios and conditional probabilities. Multivariate biometrical modeling analyses were used to assess genetic and environmental influences on co-occurrence.

RESULTS

Abusing any category of drug was associated with a marked increase in the probability of abusing every other category of drugs. We found evidence for a shared or common vulnerability factor that underlies the abuse of marijuana, sedatives, stimulants, heroin or opiates, and psychedelics. This shared vulnerability is influenced by genetic, family environmental, and nonfamily environmental factors, but not every drug is influenced to the same extent by the shared vulnerability factor. Marijuana, more than other drugs, was influenced by family environmental factors. Each category of drug, except psychedelics, had genetic influences unique to itself (ie, not shared with other drug categories). Heroin had larger genetic influences unique to itself than did any other drug.

CONCLUSION

There are genetically and environmentally determined characteristics that comprise a shared or common vulnerability to abuse a range of illicit drugs.

Interaction of beta-L-2',3'-dideoxy-2',3'-didehydro-5-fluoro-CTP with human immunodeficiency virus-1 reverse transcriptase and human DNA polymerases: implications for human immunodeficiency virus drug design

The work reported in this article has evaluated the relative molecular activity of the 5'-triphosphate of a novel beta-L-nucleoside with an unsaturated ribose residue, beta-L-2', 3'-dideoxy-2',3'-didehydro-5-fluorocytidine (beta-L-Fd4CTP), with that of beta-L-2',3'-dideoxy-5-fluorocytidine (beta-L-FddCTP) and 2', 3'-dideoxycytidine (ddCTP), on DNA strand elongation by human immunodeficiency virus-1 reverse transcriptase (HIV RT) and human DNA polymerases alpha (pol alpha), beta (pol beta), gamma (pol gamma), and epsilon (pol epsilon). The concentrations of beta-L-Fd4CTP that inhibited the yield of products by 50% were 0.20 micro M, 1.8 micro M, and 4.0 micro M for HIV RT, pol gamma, and pol beta, respectively. The beta-L-Fd4CTP at a concentration as high as 40 micro M had no inhibitory effect on pol epsilon, but could inhibit pol alpha by 10-20% at 20 micro M. The Km and relative Vmax values of beta-L-Fd4CTP, beta-L-FddCTP, and ddCTP for incorporation into the standing start point of 5'-[32P]-oligonucleotide primer annealed with M13mp19 phage DNA by HIV RT and human DNA polymerases were evaluated. The efficiency of incorporation (Vmax/Km) of beta-L-Fd4CTP by HIV RT was about 4-fold and 12-fold higher than that of ddCTP and beta-L-FddCTP, respectively. In contrast, the Vmax/Km ratio of beta-L-Fd4CTP for pol gamma was 7-fold lower than that of ddCTP, but 4-fold higher than that of beta-L-FddCTP. Pol alpha could use beta-L-Fd4CTP as a substrate, but only at a high concentration (>20 micro M). Incorporation of beta-L-Fd4CTP by pol epsilon could not be detected. A hypothesis about the preferable recognition of the 2',3'-dideoxy-2',3'-didehydro- structure of beta-L-Fd4CTP to that of the 2',3'-dideoxy-structure of beta-L-FddCTP by HIV RT is discussed.

Usefulness of positive troponin-T and negative creatine kinase levels in identifying high-risk patients with unstable angina pectoris

Troponin-T was measured in patients with chest pain and negative creatine phosphokinase-MB isoenzymes. Patients with elevated troponin-T had a significantly greater risk of cardiac events over the next 6 months than patients with normal troponin-T.

Changing care staff approaches to the prevention and management of aggressive behaviour in a residential treatment unit for persons with mental retardation and challenging behaviour

The impact of a new training procedure aimed at improving staff skills in the preventative and reactive management of severely challenging behaviours was investigated within a six-place residential treatment unit. The results showed that there was some evidence to support the notion that the training reduced the number of behavioural incidents for most residents. The rates of major reactive strategy use (restraint and emergency medication) also declined over time, as did rates of staff and resident injury. Although only a limited number of these changes showed statistically significant correlations with time, it is argued that they were clinically significant when viewed against the complexity of the client group under study.

Reversible acute renal failure induced by losartan in a renal transplant recipient

A 56-year-old man who received a live-related renal transplant in 1988 was started in 1995 on the selective angiotensin II antagonist losartan (Dupont-Merke) to treat worsening hypertension. Two months later because of pulmonary oedema, loop diuretics were started. Within two weeks, serum creatinine had increased from 245 to 571 mumol/l, and the patient became oliguric. A systolic bruit was noted over the graft. Renal angiography showed a 90% stenosis of the transplant renal artery. Losartan was withdrawn, with prompt improvement in renal function. A successful percutaneous transluminal angioplasty performed a few days later resulted in further improvement in renal function accompanied by a significant diuresis.

Movement of yeast cortical actin cytoskeleton visualized in vivo

Fusion proteins between the green fluorescent protein (GFP) and the cytoskeleton proteins Act1p (actin), Sac6p (yeast fimbrin homolog), and Abp1p in budding yeast (Saccharomyces cerevisiae) localize to the cortical actin patches. The actin fusions could not function as the sole actin source in yeast, but fusions between the actin-binding proteins Abp1p and Sac6p complement fully the phenotypes associated with their gene deletions. Direct observation in vivo reveals that the actin cortical patches move. Movement of actin patches is constrained to the asymmetric distribution of the patches in growing cells, and this movement is greatly reduced when metabolic inhibitors such as sodium azide are added. Fusion protein-labeled patches are normally distributed during the yeast cell cycle and during mating. In vivo observation made possible the visualization of actin patches during sporulation as well.

Pulmonary vein stenosis

Pulmonary vein stenosis (PVS) is a rare disorder. Accurate diagnosis often requires anatomical examination. We report four children with pulmonary vein stenosis. Autopsy showed bilateral lesions in two patients who were thought clinically to have unilateral disease. A diagnosis of PVS was made at autopsy in the third case. Intimal and medial fibromuscular proliferation was noted in extrapulmonary and intrapulmonary veins. Some of the fibromuscular proliferation were eccentric, resembling organized thrombi. In one case a focal organizing thrombus was found in a clinically unobstructed but anatomically narrowed veno-atrial junction. In another case injection of contrast medium into the stenotic pulmonary vein (PV) showed anastomosis between PV and bronchial vessels as well as small pulmonary arteries. Bilateral hypertensive arteriopathy was observed in unilateral and bilateral PVS. Our histological finding of intrapulmonary venous lesions in the lobes in which PVS was not detected clinically suggests that during surgical correction of unilateral PVS multiple biopsies of the opposite lung may help to evaluate possible bilateral disease. Our study also suggests that thrombosis in a stenotic pulmonary vein may further compromise the lumen and contribute to the progression of pulmonary vein obstruction. The possible pathogenesis of bilateral pulmonary hypertensive arteriopathy in unilateral PVS also is discussed.

Immunohistochemical localization of proliferating cells, basic fibroblast growth factor and Fos protein following iliac artery balloon angioplasty in hypercholesterolemic rabbits

The restenotic process in iliac arteries of hyperlipidemic rabbits following balloon angioplasty was evaluated in a temporal sequence by monitoring smooth muscle cell (SMC) proliferation (proliferating cell nuclear antigen -PCNA marker), growth factor (basic fibroblast growth factor -bFGF) production, and Fos oncogene protein expression using immunohistochemical methods. The percutaneous transluminal angioplasty was performed in iliac artery of rabbits fed a 1% cholesterol diet, with a balloon catheter inflated from 4 to 8 atm for 2 min under cineangiographic control until an acceptable (at least 50% stenosis reduction) result was obtained. The morphometric analysis indicated that the number of PCNA-positive cells in contralateral control arteries was low, but was increased in balloon-injury. The bFGF-positive labeled cells were localized in the media and in recently-migrated SMCs within the intima. Two days following angioplasty these cells were more abundant and scattered in the entire neo-intima. After 14 days their number was still higher than that of the controls. Cellular Fos protein expression was detected in the intima and, to a lesser extent, in the media 2 hours after angioplasty. These data suggest that early expression of Fos protein and bFGF in iliac arteries of hyperlipidemic rabbits following balloon angioplasty could be involved in development of restenosis in this animal model.