Nonoperative approach to endotension

OBJECTIVE: The necessity of operative treatment of endotension after endovascular grafting of abdominal aortic aneurysms (endovascular aneurysm repair; EVAR) is under debate. The proposed causes of endotension and related treatment protocols are controversial. We report the outcome of a nonoperative approach to five patients with endotension after EVAR. METHODS: From February 1997 to August 2004, 160 patients who underwent EVAR of an infrarenal abdominal aortic aneurysm were evaluated for the incidence of endotension. According to the endovascular protocol, plain radiographs, spiral computed tomography, and angiography were performed before and after surgery for follow-up. To detect endotension, spiral computed tomography was performed by using a delayed imaging technique after the infusion of contrast medium. Endotension was defined as an aneurysm sac enlargement after EVAR without evidence of endoleak. Aneurysm sac rupture was defined as discontinuity of the calcific rim of the aneurysmal sac and the presence of intra-aneurysmal fluid outside the sac. RESULTS: We found five (3.1%) patients with endotension. Three of these experienced aneurysmal sac rupture. Only one of the three was underwent operation on experiencing sudden intestinal occlusion due to intra-abdominal adhesions. This patient had no intra-abdominal or retroperitoneal bleeding or hematoma but died after intensive care as a result of non-aneurysm-related problems. Four patients with endotension are still being closely followed up according to our surveillance protocol, and they are doing clinically well. After rupture, clear shrinking of the aneurysm sac was seen in two patients. CONCLUSIONS: Endotension after EVAR may cause subsequent aneurysm rupture. Endotension is evidently not associated with endoleak I to III provided that the endovascular graft is maintained in appropriate position and that free endovascular flow is observed. We propose to consider a nonoperative approach in the clinically asymptomatic patient with aneurysm enlargement after EVAR if endoleak is excluded by well-performed imaging techniques.     

Apolipoprotein E ε4 allele frequency is increased in Parkinson’s disease only with co-existing Alzheimer pathology

We determined the apolipoprotein E (apoE) genotype in clinically diagnosed and neuropathologically verified cases of Parkinson’s disease (PD) (n = 45), with or without Alzheimer (AD)-type changes, and compared the apoE genotype with that in healthy age-matched controls (n = 59). The PD cases were divided into two groups according to the CERAD criteria: “O + A”, with no or only uncertain histological findings of AD, and “B + C” with histological findings suggestive or indicative of AD. DNA was isolated from frozen brain samples, and the apoE genotypes were determined using polymerase chain reaction amplification and subsequent restriction analysis by HhaI enzyme. The frequency of the apoɛ4 allele (29.4%) was significantly increased in the B + C group. The odds ratio for an apoɛ4 allele in the B + C group was 2.5 as compared to controls (95% confidence interval, 1.2–5.2). In the 0 + A group, the frequency of apoɛ4 allele (13.6%) was similar to that in controls (14.4%) and the risk of an apoɛ4 allele was not increased (odds ratio 0.94). The PD cases with an apoɛ4 allele had a greater number of cortical (P = 0.02) but not nigral Lewy bodies than those without an apoɛ4 allele (P = 0.57). The results show that neuropathologically verified PD as such is not associated with increased apoɛ4 allele frequency. Received: 15 January 1998 / Revised, accepted: 24 March 1998     

Amino acids of coxsackie B5 virus are critical for infection of the murine insulinoma cell line,MIN‐6

It was shown recently that 15 successive passages of a laboratory strain of the Coxsackie B virus 5 in a mouse pancreas (CBV‐5‐MPP) resulted in apparent changes in the virus phenotype, which led to the capacity to induce a diabetes‐like syndrome in mice. For further characterization of islet cell interactions with a passaged virus strain, a murine insulinoma cell line, MIN‐6, was selected as an experimental model. The CBV‐5‐MPP virus strain was not able to replicate in MIN‐6 cells in vitro but required adaptation over a few days for progeny production and the generation of cytopathic effects. In order to determine the genetic characteristics required for virus growth in MIN‐6 cells, the whole genome of the MIN‐6‐adapted virus variant was sequenced, and critical amino acids were identified by comparing the sequence with that of a virus strain passaged repeatedly in the mouse pancreas. The results of site‐directed mutagenesis demonstrated that only one residue, amino acid 94 of VP1, is a major determinant for virus adaptation to MIN‐6 cells. J. Med. Virol. 81:296–304, 2009. © 2008 Wiley‐Liss, Inc.     

Transantral orbital decompression in the treatment of Graves' disease

A series of twenty patients operated on for severe endocrine exophthalmos is presented. All the operations were performed by removing the orbital floor, making a total ethmoidectomy and removing part of the inferior orbital margin; in some cases, a section of the lateral orbital wall was also removed. No serious complications were detected. In all but one patient there was an immediate, marked decrease in exophthalmometry. A marked decrease of the inflammatory signs of the conjunctivae was also observed within a week following surgery.     

Immunocytochemical detection of peptides in the guinea pig cochlea

Summary The cochleae of juvenile guinea pigs were investigated for the presence of several neuropeptides. Glucagon, insulin, CCK and -endorphin immunoreactive neurons and nerve fibers as well as hair cells were demonstrated by the peroxidase antiperoxidase technique. Small amounts of substance P were also found in different sites in the inner ear. In contrast, prolactin-like material could not be found at all. These findings have significance with regard to the putative role of neuropeptides in neuromodulation.     

Regional effects of donepezil and rivastigmine on cortical acetylcholinesterase activity in Alzheimer's disease

Donepezil and rivastigmine are acetylcholinesterase (AChE) inhibitors used to improve cholinergic neurotransmission and cognitive function in Alzheimer's disease (AD). This study examined direct effects of these drugs on AChE activity in the frontal, temporal, and parietal cortices in AD. Six AD patients were scanned with positron emission tomography before and after 3 months of treatment with donepezil (10 mg/day), and five AD patients were scanned before and after 3 to 5 months of treatment with rivastigmine (9 mg/day). Healthy unmedicated controls were imaged twice to evaluate the reproducibility of the method. A specific AChE tracer, [methyl-11C]N-methyl-piperidyl-4-acetate, and a 3D positron emission tomography system with MRI coregistration were used for imaging. Treatment with donepezil reduced the AChE activity (k3 values) in the AD brain by 39% in the frontal (p < 0.001, Bonferroni corrected), 29% in the temporal (p = 0.02, corrected) and 28% in the parietal cortex (p = 0.05, corrected). The corresponding levels of inhibition for rivastigmine were 37% (p = 0.003, corrected), 28% (p = 0.03, uncorrected) and 28% (p = 0.05, corrected). When the treatment groups were combined, the level of AChE inhibition was significantly greater in the frontal cortex compared to the temporal cortex (p = 0.03, corrected). The test-retest analysis with healthy subjects indicated good reproducibility for the method, with a nonsignificant 0% to 7% intrasubject variability between scans. The present study provides first evidence for the effect of rivastigmine on cortical AChE activity. Our results indicate that the pooled effects of donepezil and rivastigmine on brain AChE are greater in the frontal cortex compared to the temporal cortex in AD. This regional difference is probably related to the prominent temporoparietal reduction of AChE in AD. We hypothesize that the clinical improvement in behavioral and attentional symptoms of AD due to AChE inhibitors is associated with the frontal AChE inhibition.     

Technetium labeled small peptide radiopharmaceuticals in the identification of lung cancer

Globally, lung cancer has risen to the leading cause of cancer mortality in both sexes. Currently, the only potentially curable stage of the disease is the pulmonary nodule. Since numerous studies have documented that in any population of nodules only approximately fifty percent ultimately prove to be neoplastic, non-invasive evaluation of nodules to reduce surgical morbidity, mortality and cost is desirable. Recent nuclear medicine imaging modalities have shown promise in the accurate non-invasive characterization of pulmonary nodules. These new technologies exploit the biomolecular alterations of neoplastic cells. The somatostatin receptor is relatively over-expressed in pulmonary neoplastic tissue when compared to most benign tissue processes. A somatostatin analog-technetium ligand ((99m)Tc depreotide) has shown significant promise in the rapid, convenient, accurate and cost effective characterization of lung nodules with conventional gamma camera systems. The development of this agent required synthesis of a somatostatin receptor ligand of high affinity for the receptor subtypes operative in pulmonary neoplasia and the incorporation of technetium without loss of pharmacore specificity.     

Different brain activation patterns during production of animals versus artefacts: a PET activation study on category-specific processing

To study neural correlates of category-specific processing, we measured relative cerebral blood flow changes by PET (oxygen-15) in young healthy subjects while they produced exemplars of animals or artefacts to written subcategory prompts. In comparison to a baseline (word reading), production of animal names elicited increased rCBF in the right inferior temporal region. This fits to recent lesion data on semantic impairment with animals, as well as imaging data on object recognition and semantic retrieval. In our study, it may represent an involvement of visual imagery in generation of animal names. In contrast, production of artefact names elicited increased rCBF in frontoparietal regions previously related to attention and mental effort.     

Selective changes in the levels of nicotinic acetylcholine receptor protein and of corresponding mRNA species in the brains of patients with Parkinson's disease

Reductions in the number of neuronal nicotinic acetylcholine receptors (nAChRs) have been shown to occur in connection with Parkinson's disease (PD), but it is still unclear which subtype of this receptor is affected. In the present study we examined various nAChR subtypes employing ligand binding, as well as levels of subunit protein and mRNA in the brains of PD patients and age-matched controls. Binding of [3H]epibatidine and levels of alpha3 mRNA in the caudate nucleus and temporal cortex, but not in the hippocampus were significantly decreased in the PD brain. The level of the alpha3 protein subunit was significantly reduced in all these brain regions but there was no change in the level of alpha4. The level of the beta2 protein subunit in the temporal cortex and hippocampus and the beta2 mRNA in the temporal cortex was lowered. Both the levels of the alpha7 subunit protein and [125I]alpha-bungarotoxin binding were significantly increased in the temporal cortex of PD patients whereas the alpha7 mRNA level was unchanged. These findings reveal selective losses of the alpha3- and beta2-containing nAChRs and an increase in the alpha7 nAChRs that might be related to the pathogenesis of PD.     

Randomised,controlled walking trials in postmenopausal women: the minimum dose to improve aerobic fitness?

BACKGROUND: The American College of Sports Medicine recommends 20-60 minutes of aerobic exercise three to five days a week at an intensity of 40/50-85% of maximal aerobic power (VO(2)MAX) reserve, expending a total of 700-2000 kcal (2.93-8.36 MJ) a week to improve aerobic power and body composition. OBJECTIVE: To ascertain the minimum effective dose of exercise. METHODS: Voluntary, healthy, non-obese, sedentary, postmenopausal women (n = 121), 48-63 years of age, were randomised to four low dose walking groups or a control group; 116 subjects completed the study. The exercise groups walked five days a week for 24 weeks with the following intensity (% of VO(2)MAX) and energy expenditure (kcal/week): group W1, 55%/1500 kcal; group W2, 45%/1500 kcal; group W3, 55%/1000 kcal; group W4, 45%/1000 kcal. VO(2)MAX was measured in a direct maximal treadmill test. Submaximal aerobic fitness was estimated as heart rates at submaximal work levels corresponding to 65% and 75% of the baseline VO(2)MAX. The body mass index (BMI) was calculated and percentage of body fat (F%) estimated from skinfolds. RESULTS: The net change (the differences between changes in each exercise group and the control group) in VO(2)MAX was 2.9 ml/min/kg (95% confidence interval (CI) 1.5 to 4.2) in group W1, 2.6 ml/min/kg (95% CI 1.3 to 4.0) in group W2, 2.4 ml/min/kg (95% CI 0.9 to 3.8) in group W3, and 2.2 ml/min/kg (95% CI 0.8 to 3.5) in group W4. The heart rates in standard submaximal work decreased 4 to 8 beats/min in all the groups. There was no change in BMI, but the F% decreased by about 1% unit in all the groups. CONCLUSIONS: Walking (for 24 weeks) at moderate intensity 45% to 55% of VO(2)MAX, with a total weekly energy expenditure of 1000-1500 kcal, improves VO(2)MAX and body composition of previously sedentary, non-obese, postmenopausal women. This dose of exercise apparently approaches the minimum effective dose.