Mixed evidence for the potential of non-invasive transcutaneous vagal nerve stimulation to improve the extinction and retention of fear.

Extinction memories are fragile and their formation has been proposed to partially rely on vagus nerve activity. We tested whether stimulating the auricular branch of the vagus (transcutaneous VNS; tVNS) accelerates extinction and reduces spontaneous recovery of fear. Forty-two healthy students participated in a 3-day fear conditioning study, where we tested fear acquisition (day 1), fear extinction (day 2) and the retention of the extinction memory (day 3). During extinction, participants were randomly allocated to receive tVNS or sham stimulation concurrently with each CS presentation. During the acquisition and retention phases, all participants received sham stimulation. Indexes of fear included US-expectancy, startle blink EMG and skin conductance responses. Results showed successful acquisition and extinction of fear in all measures. tVNS facilitated the extinction of declarative fear (US expectancy ratings), but did not promote a stronger retention of the declarative extinction memory. No clear effects of tVNS on extinction and retention of extinction were found for the psychophysiological indexes. The present findings provide tentative indications that tVNS could be a promising tool to improve fear extinction and call for larger scale studies to replicate these effects.

Role of Ki-67 proliferation index in the assessment of patients with neuroendocrine neoplasias regarding the stage of disease.

BACKGROUND: Neuroendocrine neoplasias (NEN) of the gastroenteropancreatic (GEP) system frequently present with metastatic deposits. The proliferation marker Ki-67 is used for diagnosis and to assess the prognosis of disease. The aim of our study was to evaluate the usefulness of Ki-67 % in the assessment of NEN patients with regard to their disease stage in clinical practice. Additionally, a comparative analysis of Ki-67 levels among different sites of disease was performed. METHODS: This retrospective study included patients with GEP NEN referred to our center from 2010 to 2012. The NEN diagnosis was confirmed by standard histopathology. Ki-67 immunohistochemistry was done on paraffin-embedded sections using an automated Leica immunohistochemistry machine. NEN grading was carried out according to European Neuroendocrine Tumor Society recommendations (low grade [G1] to intermediate grade [G2], well to moderately differentiated neuroendocrine neoplasms; high-grade [G3], moderately to poorly differentiated neuroendocrine neoplasms). Results of tumor staging and grading were correlated. In a subgroup of cases, comparative analysis of Ki-67 levels in different sites of disease was carried out. RESULTS: One hundred sixty-one GEP NEN patients were included in the study. Metastatic disease was seen in 46.1 % (53/115) of G1 tumors, 77.8 % (28/36) of G2 tumors, and 100 % of (10/10) G3 tumors (p = 0.0002). When stratified according to primary tumor site, metastatic disease was documented in 42.9 % (36/84) of patients with pancreatic NEN and in 91.9 % (34/37) of those with small intestinal primary. Stage IV metastatic disease was present in 27.8 % (32/115) and 72.2 % (26/36) of the G1 and G2 tumors, respectively, and in 90 % (9/10) of the G3 tumors. Assessment of the Ki-67 index for a subset of cases at metastatic sites as well as the primary tumor site showed discrepancies in 35.3 % cases. In 7/9 (77.8 %) patients with liver metastases, Ki-67 % was higher in the liver lesions than in the primary tumor. CONCLUSIONS: Patients with GEP NEN exhibiting a high Ki-67 proliferation index present with metastatic disease in the vast majority of cases. Depending upon the primary tumor site, metastases are to be expected also in tumors with low Ki-67 %, although they are considered less aggressive. Different disease sites may express heterogeneous Ki-67 levels.

Fine-scale genetic structure of a long-lived reptile reflects recent habitat modification.

Anthropogenic habitat fragmentation--ubiquitous in modern ecosystems--has strong impacts on gene flow and genetic population structure. Reptiles may be particularly susceptible to the effects of fragmentation because of their extreme sensitivity to environmental conditions and limited dispersal. We investigate fine-scale spatial genetic structure, individual relatedness, and sex-biased dispersal in a large population of a long-lived reptile (tuatara, Sphenodon punctatus) on a recently fragmented island. We genotyped individuals from remnant forest, regenerating forest, and grassland pasture sites at seven microsatellite loci and found significant genetic structuring (R(ST)=0.012) across small distances (<500 m). Isolation by distance was not evident, but rather, genetic distance was weakly correlated with habitat similarity. Only individuals in forest fragments were correctly assignable to their site of origin, and individual pairwise relatedness in one fragment was significantly higher than expected. We did not detect sex-biased dispersal, but natural dispersal patterns may be confounded by fragmentation. Assignment tests showed that reforestation appears to have provided refuges for tuatara from disturbed areas. Our results suggest that fine-scale genetic structuring is driven by recent habitat modification and compounded by the sedentary lifestyle of these long-lived reptiles. Extreme longevity, large population size, simple social structure and random dispersal are not strong enough to counteract the genetic structure caused by a sedentary lifestyle. We suspect that fine-scale spatial genetic structuring could occur in any sedentary species with limited dispersal, making them more susceptible to the effects of fragmentation.

Twenty year comparison of a Bjork-Shiley mechanical heart valve with porcine bioprostheses.

OBJECTIVE: To compare survival and outcome in patients receiving a mechanical or bioprosthetic heart valve prosthesis. DESIGN: Randomised prospective trial. SETTING: Tertiary cardiac centre. PATIENTS: Between 1975 and 1979, patients were randomised to receive either a Bjork-Shiley or a porcine prostheses. The mitral valve was replaced in 261 patients, the aortic in 211, and both valves in 61 patients. Follow up now averages 20 years. MAIN OUTCOME MEASURES: Death, reoperation, bleeding, embolism, and endocarditis. RESULTS: After 20 years there was no difference in survival (Bjork-Shiley v porcine prosthesis (mean (SEM)): 25.0 (2.7)% v 22.6 (2.7)%, log rank test p = 0.39). Reoperation for valve failure was undertaken in 91 patients with porcine prostheses and in 22 with Bjork-Shiley prostheses. An analysis combining death and reoperation as end points confirmed that Bjork-Shiley patients had improved survival with the original prosthesis intact (23.5 (2.6)% v 6.7 (1.6)%, log rank test p < 0.0001); this difference became apparent after 8-10 years in patients undergoing mitral valve replacement, and after 12-14 years in those undergoing aortic valve replacement. Major bleeding was more common in Bjork-Shiley patients (40.7 (5.4)% v 27.9 (8.4)% after 20 years, p = 0.008), but there was no significant difference in major embolism or endocarditis. CONCLUSIONS: Survival with an intact valve is better among patients with the Bjork-Shiley spherical tilting disc prosthesis than with a porcine prosthesis but there is an attendant increased risk of bleeding.

Enhanced expression of intercellular adhesion molecule-1 (ICAM-1) in amnion with term and preterm labour.

To evaluate the association between intercellular adhesion molecule-1 (ICAM-1) in the amnion and preterm labour and delivery, we have assessed ICAM-1 mRNA abundance by Northern analysis and protein levels by enzyme-linked immunosorbent assay (ELISA), in samples of this tissue after term and preterm delivery. The median ICAM-1 mRNA expression following preterm delivery (PTD, n=30) was 24 times greater (P< 0.05) than following elective caesarean section prior to labour at term (CST, n=14). ICAM-1 expression following vaginal delivery after spontaneous labour at term (SLT, n=11) was seven times greater than in the CST group (P< 0.05). The concentration of ICAM-1 protein in the PTD samples (n=31) was four-fold greater than (P< 0.05) in CST (n=14). It was also three-fold greater than in the SLT (n=15) samples (P< 0.05). The results were substantially the same when a preterm spontaneous labour group (PTL) (n=26), exclusive of deliveries complicated by pre-eclampsia (n=1) or intrauterine growth restriction (n=3), was compared to the CST and SLT groups. The ICAM-1 mRNA expression did not differ significantly (P=0.93) between PTL with (n=12) or without (n=14) indicators of intrauterine infection. The results were similar when ICAM-1 protein concentrations were compared (P=0.43) between these two groups. These findings indicate that ICAM-1 is expressed by the human amnion and that this expression is elevated with preterm labour and delivery.

Have complication rates decreased after treatment for localized prostate cancer?

PURPOSE: The American Urological Association Prostate Cancer Clinical Guidelines Panel reviewed 12,501 publications on prostate cancer from 1955 to 1992 to determine whether the complication rates of external beam radiation therapy, interstitial radiotherapy and radical prostatectomy have decreased. MATERIALS AND METHODS: Complications reported in at least 6 series, study duration and sample sizes were extracted. Year specific study weighted mean patient ages and complication rates were computed. Regression analysis was performed of the study year on weighted mean patient age and complication rate. RESULTS: Study year had a significant effect on mean patient age and rate of the majority of complications examined. Data indicated a gradual increase in study patient age and a simultaneous decrease in complications from 1960 to 1990. CONCLUSIONS: Complication rates in the treatment of localized prostate cancer have decreased during the last 20 to 40 years. This decrease occurred despite evidence that the average age of treated patients had increased during the same period.

Amnion-derived cells express intercellular adhesion molecule-1: regulation by cytokines.

We have examined the expression of the intercellular adhesion molecule-1 (ICAM-1) mRNA in primary and established amnion-derived cell cultures and regulation of this expression by tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-1beta. TNF-alpha (50 ng/ml) and IL-1beta (1.0 ng/ml) induced 18- and 11-fold increases respectively in expression of the ICAM-1 mRNA in WISH cells (an amnion epithelium-derived cell line). The increase was detectable within one hour of treatment and peaked by two hours. The protein synthesis inhibitor, cycloheximide (10 microg/ml) did not inhibit this induction. Increased levels of ICAM-1 protein were detected in the cells within 4 h after initiation of treatment with either cytokine. By 16 h of treatment with IL-1beta or TNF-alpha ICAM-1 reached 40 and 73 pg/microg cellular protein, representing 6- and 11-fold stimulations respectively. In primary amnion cells, basal expression of ICAM-1 mRNA was undetectable. However, TNF-alpha (50 ng/ml) induced ICAM-1 mRNA within two hours, peak expression being reached between four and eight hours after initiation of treatment. The present report demonstrates for the first time that amnion derived cells can express ICAM-1 and, further, that this expression is regulated by pro-inflammatory cytokines. This has implications for the amnion as a possible source for soluble ICAM-1, for this gene product as a marker for preterm labour, and for participation of the amnion, additional to its reported secretory role, in inflammatory processes of the fetal membranes.

Effects of interleukin-4 on the expression and activity of prostaglandin endoperoxide H synthase-2 in amnion-derived WISH cells.

Increased prostaglandin biosynthesis during intrauterine infection may be a possible mechanism by which preterm labour is initiated. Inflammatory cytokines and growth factors are known to stimulate prostaglandin production through an increase in prostaglandin endoperoxide H synthase (PGHS)-2 synthesis and activity. Interleukin-4 (IL-4), an anti-inflammatory cytokine, can downregulate PGHS-2 expression and inhibit prostaglandin production. Therefore, the aims of the current study were to determine the effects of IL-4 on PGHS-1 and PGHS-2 expression in amion-derived WISH cells treated with inflammatory cytokines and growth factors. In WISH cells, near-maximal production of the PGHS-2 mRNA occurred using 5 ng/ml EGF, 1 ng/ml IL-1beta or 50 ng/ml TNF-alpha. Time-course experiments determined that the PGHS-2 mRNA was induced maximally by these stimuli by 1 h. Pretreatment of WISH cells with IL-4 reduced PGHS-2 mRNA levels at 1 h by 67% in cells treated with EGF, 62% in cells treated with IL-1beta and 54% in cells treated with TNF-alpha. Pretreatment with IL-4 more effectively inhibited PGHS-2 expression than simultaneous addition with EGF or IL-1beta but not TNF-alpha. Immunoblot analysis showed a correlation between inhibition of mRNA levels and levels of PGHS-2 protein, although stimulation of PGHS-2 protein production by EGF was undetectable. Levels of PGHS-1 protein and mRNA remained unchanged in all experiments. Increased production of prostaglandin E2 (PGE2) in response to TNF-alpha and IL-1beta treatment was attenuated by IL-4 pretreatment, by 52% and 72%, respectively. No attenuation of EGF-stimulated PGE2 levels was seen. We conclude that IL-4 inhibits PGHS-2 mRNA and protein production in cytokine-stimulated WISH cells, but does not affect EGF-stimulated PGE2 production, suggesting that EGF can induce prostaglandin biosynthesis by a mechanism other than through increased PGHS-2 expression.

Atrioventricular block occurring several months after radiofrequency ablation for the treatment of atrioventricular nodal re-entrant tachycardia.

Atrioventricular (AV) block following radiofrequency (RF) ablation for the treatment of AV nodal re-entrant tachycardia (AVNRT) is a rare but well recognised complication of the procedure--the reported incidence ranges from 1% to 21%. Almost all cases of AV block occur during or shortly after the procedure, are transient, and recover quickly. Two patients (a 22 year man and a 72 year old woman) with symptomatic AV block occurring several months after slow pathway RF ablation, requiring permanent pacemaker implantation, are described. Both patients had had several 24 hour Holter recordings before the procedure, and in neither case was there any evidence of intermittent or persistent AV block. This is a rare complication with no definitive predictors; however, all efforts should be made to exclude AV block in patients presenting with suggestive symptoms following RF ablation. With the wide use of RF ablation for the treatment of AVNRT, more cases are likely to occur. A registry should allow documentation of the incidence of this complication.

Effectiveness of five days of therapy with cefuroxime axetil suspension for treatment of acute otitis media.

BACKGROUND: In recent years there has been considerable interest in reducing the duration of antibiotic treatment regimens in patients with common bacterial infections. We conducted two independent, investigator-blinded, multicenter, randomized clinical trials, one of which included microbiologic evaluation of middle ear fluid obtained by tympanocentesis, comparing the efficacy and safety of 5 or 10 days of treatment with cefuroxime axetil suspension (CAE) with that of 10 days of treatment with amoxicillin/clavulanate suspension (AMX/CL) in children with acute otitis media. METHODS: A total of 719 pediatric patients from the ages of 3 months to 12 years were enrolled in the 2 studies. Patients received CAE for either 5 or 10 days at 30 mg/kg/day in 2 divided doses (n = 242 and 235, respectively) or AMX/CL for 10 days at 40 mg/kg/day in 3 divided doses (n = 242). Patients in the CAE (5 days) group received placebo on Days 6 through 10. In the study that included tympanocentesis, bacteriologic assessments were based on middle ear fluid cultures obtained pretreatment and, when possible, after treatment in patients with an unsatisfactory clinical outcome. RESULTS: Organisms were isolated from the pretreatment middle ear fluid specimens of 177 of 244 (73%) patients undergoing tympanocentesis, with the primary pathogens being Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis (37, 35 and 12% of isolates, respectively). Pathogens were eradicated or presumed to be eradicated in 92% (24 of 26), 84% (32 of 38) and 95% (36 of 38) of bacteriologically evaluable patients treated with CAE for 5 or 10 days or with AMX/CL, respectively. A satisfactory clinical outcome (cure or improvement) occurred in 69% (101 of 147), 70% (121 of 173) and 74% (131 of 177) of clinically evaluable patients treated with CAE (5 days), CAE (10 days) or AMX/CL, respectively. Treatment with AMX/CL was associated with a significantly higher incidence of drug-related adverse events than was treatment with CAE for either 5 or 10 days (P < 0.001), primarily reflecting a higher incidence of drug-related gastrointestinal adverse events (34% vs. 17 and 12%, respectively; P < 0.001), particularly diarrhea. CONCLUSIONS: Treatment with CAE given twice daily for 5 days is equivalent to treatment for 10 days either with the same regimen of CAE or with AMX/CL given three times daily in pediatric patients with acute otitis media.

Prostate Cancer Clinical Guidelines Panel Summary report on the management of clinically localized prostate cancer. The American Urological Association.

PURPOSE: The American Urological Association convened the Prostate Cancer Clinical Guidelines Panel to analyze the literature regarding available methods for treating locally confined prostate cancer, and to make practice policy recommendations based on the treatment outcomes data insofar as the data permit. MATERIALS AND METHODS: The panel searched the MEDLINE data base for all articles from 1966 to 1993 on stage T2 (B) prostate cancer and systematically analyzed outcomes data for radical prostatectomy, radiation therapy and surveillance as treatment alternatives. Outcomes considered most important were survival at 5, 10 and 15 years, progression at 5, 10 and 15 years, and treatment complications. RESULTS: The panel found the outcomes data inadequate for valid comparisons of treatments. Differences were too great among treatment series with regard to such significant characteristics as age, tumor grade and pelvic lymph node status. The panel elected to display, in tabular form and graphically, the ranges in outcomes data reported for each treatment alternative. CONCLUSIONS: In making its recommendations, the panel presented treatment alternatives as options, identifying the advantages and disadvantages of each, and recommended as a standard that patients with newly diagnosed, clinically localized prostate cancer should be informed of all commonly accepted treatment options.

Clinical comparison of cefuroxime axetil suspension and amoxicillin/clavulanate suspension in the treatment of pediatric patients with acute otitis media with effusion.

Two independent, investigator-blinded, multicenter, randomized clinical trials, one of which included microbiologic evaluation of middle-ear fluid obtained by use of tympanocentesis, compared the efficacy and safety of two oral antibiotics, cefuroxime axetil suspension and amoxicillin/clavulanate suspension, in the treatment of children 3 months to 12 years old diagnosed with acute otitis media with effusion (AOME). Four hundred seventy-seven pediatric patients with signs and symptoms of AOME were enrolled at 20 centers and were randomly assigned to receive 10 days of treatment with either cefuroxime axetil suspension 30 mg/kg per day in two divided doses (n = 235) or amoxicillin/clavulanate suspension 40 mg/kg per day in three divided doses (n = 242). Patients were assessed for their response to treatment once during treatment (at 3 to 5 days) and twice after treatment (at 1 to 4 days and at 14 to 18 days). In the study that included tympanocentesis, bacteriologic assessments were based on middle-ear fluid cultures obtained pretreatment, and, when possible, posttreatment in patients with an unsatisfactory clinical outcome. Organisms were isolated from the pretreatment middle-ear fluid specimens of 120 (73%) of 164 patients undergoing tympanocentesis, with the primary pathogens being Streptococcus pneumoniae. Haemophilus influenzae, and Moraxella catarrhalis (27%, 24%, and 6% of isolates, respectively). Forty-four percent of the H influenzae isolates and 94% of the M catarrhalis isolates that were tested for beta-lactamase production were positive. A satisfactory clinical outcome (cure or improvement) was obtained in 70% of clinically assessable patients treated with cefuroxime axetil or amoxicillin/clavulanate, respectively (P = 0.40). With respect to the eradication of bacterial pathogens, in the study that included tympanocentesis a satisfactory outcome (cure or presumed cure) was obtained in 84% (32 of 38) and 95% (36 of 38) of bacteriologically assessable patients treated with cefuroxime axetil or amoxicillin/clavulanate, respectively (P = 0.26). Treatment with amoxicillin/clavulanate was associated with a significantly higher incidence of drug-related adverse events than was treatment with cefuroxime axetil (37% vs 16%; P < 0.001), primarily reflecting a higher incidence of drug-related gastrointestinal adverse events (34% vs 12%; P < 0.001), particularly diarrhea. Eight patients in the cefuroxime axetil group and 11 patients in the amoxicillin/clavulanate group withdrew from the studies because of drug-related adverse events. These results indicate that cefuroxime axetil suspension 15 mg/kg twice daily is as effective as amoxicillin/clavulanate suspension 13.3 mg/kg three times daily in the treatment of pediatric patients with AOME, but produces fewer gastrointestinal adverse events, particularly diarrhea.

Vascular interventions for impotence: lessons learned.

PURPOSE: The purpose of this study was to analyze the results of vascular interventions for impotence in men with this complaint. METHODS: Between September 1983 and March 1993, 1094 men with the chief complaint of impotence (average age 54.5 years) were screened by use of penile plethysmography and penile brachial indexes: 635 were considered to have normal flow, and 459 were considered to have abnormal arterial flow, 12.2% of whom were found to have aortoiliac disease. Based on negative neural screening results, absence of erectile responses on increasing doses of intracavernously injected papaverine or prostaglandin E1 (ICI), surgical candidates for microvascular procedures were referred for dynamic infusion cavernosography (DICC) and pudendal arteriography. Operations for men discovered to have aortoiliac disease were based on conventional indications including aneurysm size or limb ischemia. None of the subjects had diabetes. Only those patients without diabetes and those not requiring blood pressure medications were selected for microvascular procedures. We report our experience and surgical outcomes at average follow-ups of 33 to 48 months. Four types of operations were performed on 67 men (age 18 to 79 years). These included 17 aortoiliac reconstructions, 11 dorsal penile artery bypasses, 12 dorsal vein arterializations, and 27 venous interruptions. Follow-up data were obtained by direct examination and noninvasive Doppler examinations; repeat arteriography (4 of 11); repeat DICC after venous ablation procedures (18 of 27) and postoperative ICI response. Mail questionnaires completed postoperative surveillance. RESULTS: Among 17 men undergoing aortoiliac intervention for aneurysms in eight and occlusive disease in nine, 58% functioned spontaneously after operation and 18% used ICI or vacuum constrictor devices at an average follow-up time of 38 months. Among 11 men with dorsal penile artery bypasses, 27% functioned spontaneously and 45% used ICI at an average follow-up time of 34.5 months. Among 12 men with dorsal vein arterialization, 33% functioned spontaneously, and 47% used ICI at an average follow-up time of 48 months. Among 27 with venous interruption, 33% functioned spontaneously and 44% used ICI. In seven of eight aneurysms of 4.5 to 6.0 cm in size, impotence workup led to discovery; probable embolic mechanisms existed in three. Venous interruption efficacy correlated with postoperative DICC results when flow to maintain erection was 40 ml or less. Apart from two cases of glans hyperemia, no surgical complications occurred in the microvascular procedures. There was one episode of bleeding caused by DICC after aortic reconstruction. There were no deaths. CONCLUSIONS: With prospective screening criteria, 6% to 7% of impotent men became candidates for vascular intervention. Including those functioning with ICI or vacuum constriction devices, about 70% of these men were functional after operation. Men undergoing aortoiliac reconstruction has a significantly higher rate (58%) of spontaneous function as compared with those undergoing microvascular procedures.

Human immune response to Pseudomonas aeruginosa mucoid exopolysaccharide (alginate) vaccine.

Chronic lung infection with mucoid Pseudomonas aeruginosa is the major pathologic feature of cystic fibrosis. Previous studies suggested that a failure to produce opsonic antibody to the mucoid exopolysaccharide (MEP; also called alginate) capsule is associated with the maintenance of chronic bacterial infection. Provision of MEP-specific opsonic antibodies has therapeutic potential. To evaluate the ability of MEP to elicit opsonic antibodies, humans were immunized with two lots of MEP vaccine that differed principally in molecular size. Lot 2 had a larger average MEP polymer size. Both vaccines were well tolerated, but lot 1 was poorly immunogenic, inducing long-lived opsonic antibodies in only 2 of 28 vaccinates given doses of 10 to 150 micrograms. In contrast, at the optimal dose of 100 micrograms, lot 2 elicited long-lived opsonic antibodies in 80 to 90% of the vaccinates. The antibodies elicited by both lots enhanced deposition of C3 onto mucoid P. aeruginosa cells and mediated opsonic killing of heterologous mucoid strains expressing distinct MEP antigens. These results indicate that the polymers of MEP with the largest molecular sizes safely elicit opsonic antibodies in a sufficiently large proportion of vaccinates to permit studies of active and passive immunization of cystic fibrosis patients against infection with mucoid P. aeruginosa.

The need for alternatives to capitation under managed care.

Health reform requires the merging of traditional insurance and health financing tools. At the center of this intersection may be the need for risk adjustment of capitated payments. For ambulatory services ACGs and capitation are but one possible fate for provider payment in a managed care-dominated future. It is the authors' opinion that such an approach fails to meet the demands of risk adjustment as well as other needs related to provider payment under managed care and health reform.

Hemorrhagic varicella: a case report and review of the complications of varicella in children.

The case of a previously healthy child who developed progressive systemic varicella with purpura is reported. The clinical course of this patient is outlined, and the range of potential complications of chickenpox in children is reviewed. Familiarity with the usual uncomplicated natural history of primary varicella infection should alert the clinician to signs and symptoms that signal significant systemic involvement.