A newly designed uncovered biliary stent for palliation of malignant obstruction: results of a prospective study.

BACKGROUND: Biliary decompression can reduce symptoms and improve quality of life in patients with malignant biliary obstruction. Endoscopically placed stents have become the standard of care for biliary drainage with the aim of improving hepatic function, relieving jaundice, and reducing adverse effects of obstruction. The purpose of this study was to evaluate the performance characteristics of a newly-designed, uncovered metal biliary stent for the palliation of malignant biliary obstruction. METHODS: This post-market, prospective study included patients with biliary obstruction due to a malignant neoplasm treated with a single-type, commercially available uncovered self-expanding metal stent (SEMS). Stents were placed as clinically indicated for palliation of jaundice and to potentially facilitate neo-adjuvant chemotherapy. The main outcome measure was freedom from recurrent biliary obstruction (within the stent) requiring re-intervention within 1, 3, and 6 months of stent insertion. Secondary outcome measures included device-related adverse events and technical success of stent deployment. RESULTS: SEMS were placed in 113 patients (73 men; mean age, 69); a single stent was inserted in 106 patients, and 2 stents were placed in 7 patients. Forty-eight patients survived and/or completed the 6 month study protocol. Freedom from symptomatic recurrent biliary obstruction requiring re-intervention was achieved in 108 of 113 patients (95.6, 95%CI = 90.0-98.6%) at study exit for each patient. Per interval analysis yielded the absence of recurrent biliary obstruction in 99.0% of patients at 1 month (n = 99; 95%CI = 97.0-100%), 96.6% of patients at 3 months (n = 77; 95%CI = 92.7-100%), and 93.3% of patients at 6 months (n = 48; 95%CI = 86.8-99.9%). In total, only 5 patients (4.4%) were considered failures of the primary endpoint. Most of these failures (4/5) were due to stent occlusion from tumor ingrowth or overgrowth. Overall technical success rate of stent deployment was 99.2%. There were 2 cases of stent-related adverse events (1.8%). There were no cases of post-procedure stent migration, stent-related perforation, or stent-related deaths. CONCLUSIONS: This newly designed and marketed biliary SEMS system appears to be effective at relieving biliary obstruction and preventing re-intervention within 6 months of insertion in the overwhelming majority of patients. The device has an excellent safety profile, and associated high technical success rate during deployment. TRIAL REGISTRATION: The study was registered on clinicaltrials.gov on 14 October 2013 and the study registration number is NCT01962168. University of Massachusetts Medical School did not participate in the study.

The genetics of cholesteatoma. A systematic review using narrative synthesis.

OBJECTIVE: A cholesteatoma is a mass of keratinising epithelium in the middle ear. It is a rare disorder that is associated with significant morbidity, and its causative risk factors are poorly understood; on a global scale, up to a million people are affected by this each year. We have conducted a systematic literature review to identify reports about the heritability of cholesteatoma or any constitutional genetic factors that may be associated with its aetiology. DATA SOURCES: A systematic search of MEDLINE (EBSCO) and two databases of curated genetic research (OMIM and Phenopedia) was conducted. STUDY SELECTION: The participants and populations of interest for this review were people treated for cholesteatoma and their family members. The studies of interest reported evidence of heritability for the trait, or any association with congenital syndromes and particular genetic variants. DATA EXTRACTION: The searches identified 449 unique studies, of which 35 were included in the final narrative synthesis. DATA SYNTHESIS: A narrative synthesis was conducted, and data were tabulated to record characteristics, including study design, genetic data and author conclusions. Most of the studies identified in the literature search, and described here, are case reports and so represent the lowest level of evidence. In a few case reports, congenital and acquired cholesteatomas have been shown to segregate within families in the pattern typical of a monogenic or oligogenic disorder with incomplete penetrance. Evidence from syndromic cases could suggest that genes controlling ear morphology may be risk factors for cholesteatoma formation. CONCLUSIONS: This is the first systematic review about the genetics of cholesteatoma, and we have identified a small body of relevant literature that provides evidence of a heritable component for its aetiology. Cholesteatoma is a complex and heterogeneous clinical phenotype, and it is often associated with chronic otitis media and with some rare congenital syndromes known to affect ear morphology and related pathologies.

Young women with polycystic ovary syndrome have raised levels of circulating annexin V-positive platelet microparticles.

STUDY QUESTION: Are circulating microparticles (MPs) altered in young women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Women with PCOS have elevated concentrations of circulating platelet-derived MPs, which exhibit increased annexin V binding and altered microRNA (miR) profiles compared with healthy volunteers. WHAT IS KNOWN ALREADY: Some studies have shown that cardiovascular risk is increased in young women with PCOS but the mechanisms by which this occurs are uncertain. Circulating MPs are elevated in patients with cardiovascular disease but the characteristics of MPs in patients with PCOS are unclear. STUDY DESIGN, SIZE, DURATION: Case-control study comprising 17 women with PCOS (mean ± SD; age 31 ± 7 years, BMI 29 ± 6 kg/m(2)) and 18 healthy volunteers (age 31 ± 6 years, BMI 30 ± 6 kg/m(2)). PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted in a University hospital. Nanoparticle tracking analysis (NTA) and flow cytometry (CD41 platelet, CD11b monocyte, CD144 endothelial) were used to determine MP size, concentration, cellular origin and annexin V positivity (reflecting phosphatidylserine exposure). Fatty acid analysis was performed by gas chromatography and MP miR expression profiles were compared by microarray. MAIN RESULTS AND THE ROLE OF CHANCE: PCOS subjects showed increased MP concentrations compared with healthy volunteers (mean ± SD; 11.5 ± 5 × 10(12)/ml versus 10.0 ± 4 × 10(12)/ml, respectively; P = 0.03), which correlated with the homeostasis model of insulin resistance (r = 0.53, P = 0.03). This difference was predominantly seen in MPs whose size was in the small exosomal range (<150 nm in diameter, P< 0.05). PCOS patients showed a greater percentage of annexin V(+) MPs compared with healthy volunteers (84 ± 18 versus 74 ± 24%, respectively, P = 0.05) but the cellular origin of MPs, which were predominantly platelet-derived (PCOS: 99 ± 0.9%; controls: 99 ± 2.5%), did not differ. MP fatty acid concentration and composition was similar between groups but 16 miRs were differentially expressed (P < 0.05). LIMITATIONS, REASON FOR CAUTION: Patients with PCOS were classified by the Rotterdam criteria, which describes a less severe metabolic phenotype than other definitions of the syndrome. Our findings may thus not be generalizable to all patients with PCOS. MicroRNA expression analysis was only undertaken in an exploratory subset of the overall study population hence, validation of our findings in a larger cohort is mandatory. Furthermore, miR levels were unaltered for the highly expressed miRs and it is unclear whether differences in the lowly expressed miRs carries pathological relevance. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that women with PCOS have an altered MP profile but further studies are needed to confirm this, to explore the mechanisms by which these alterations develop and to establish whether therapies that improve insulin sensitivity are able to reduce circulating MP concentrations. STUDY FUNDING/COMPETING INTERESTS: The study was funded by grants from the Wales Heart Research Institute and Mrs John Nixon Scholarship. The authors have no conflicts of interest to declare.

Detailed characterisation of circulatory nitric oxide and free radical indices--is there evidence for abnormal cardiovascular homeostasis in young women with polycystic ovary syndrome?

OBJECTIVE: To assess circulating biochemical indices of endothelial function and nitro-oxidative stress in women with polycystic ovary syndrome (PCOS). DESIGN: Case-control study. POPULATION: Seventeen women with PCOS and eighteen age- and body mass index-matched healthy volunteers. METHODS: Nitric oxide (NO) metabolite levels were assessed by chemiluminescence. Electron paramagnetic resonance spectroscopy with spin trapping was used to assess oxidative stress ex vivo and in vitro. Antioxidant capacity was measured using oxygen radical absorbance. MAIN OUTCOME MEASURES: Biochemical indices of endothelial function, including NO metabolites, lipid-derived radicals and antioxidant capacity. RESULTS: Plasma NO metabolites were similar in the two groups (nitrite: 257±116 nmol/l [PCOS], 261±135 nmol/l [controls] P=0.93; nitrate: 27±7 µmol/l [PCOS], 26±6 µmol/l [controls] P=0.89). Alkoxyl free radicals (lipid-derived) were detected as the dominant species, but levels were not different between women with PCOS and controls whether measured directly ex vivo (median 7.2 [range 0.17-16.73]e6 arbitrary units [a.u.] and 7.2 [1.7-11.9]e6 a.u., respectively, P=0.57) or when stimulated in vitro to test radical generation capacity (1.23 [0.3-5.62]e7 a.u. and 1.1 [0.48-15.7]e7 a.u. respectively, P=0.71). In regression analysis, visceral fat area was independently associated with in vitro oxidative potential (ß=0.6, P=0.002). Total plasma antioxidant capacity (94±30% [PCOS], 79±24% [controls], P=0.09) and plasma hydroperoxides (7.5±4 µmol/l [PCOS], 6.7±5 µmol/l [controls], P=0.21) were not different between groups. However, lipophilic antioxidant capacity was lower in women with PCOS compared with controls (92±32 and 125±48%, respectively, P=0.02). CONCLUSIONS: Young overweight women with PCOS display a reduced lipophilic antioxidant capacity compared with healthy volunteers, but no change in circulating free radicals or nitro-oxidative stress.

Bond analysis in meta- and para-substituted thiophenols: overlap descriptors, local mode analysis, and QTAIM.

CONTEXT: This study delves into the chemical nuances of thiophenols and their derivatives through a comprehensive computational analysis, moving beyond traditional energetic perspectives such as bond dissociation enthalpy and S-H dissociation dynamics. By employing the overlap model along with its topological descriptors (OP/TOP), quantum theory of atoms in molecules (QTAIM), and local vibrational mode (LVM) theories, the research provides a deeper understanding of the S-H and C-S bonding scenarios in substituted thiophenols. The investigation follows the electron-donating capacity of S-H substituent variation with the nature and positioning of other ring substituents. Energy profile analyses indicate distinct stability differences in the cis and trans conformations of meta- and para-PhSH systems, influenced by the electron-donating strength of these substituents. The study also uncovers significant variations in S-H bond distances and descriptor values, particularly in para-substituted PhSH, reflecting the influence of electron-donating or withdrawing substituents. In contrast, alterations at the meta-position show minimal effects on C-S bond descriptors, while para-substitutions markedly influence C-S bond characteristics, demonstrating a clear correlation with the electron-donating or withdrawing capabilities of the substituents. This research sheds light on the intricate bond dynamics in aromatic systems with diverse substituents, highlighting the complex interaction between electronic effects and molecular conformation. METHODS: The study employs the ω B97X-D/Def2TZVP level of theory for molecular geometries, ensuring accurate characterization of structures as true minima via analytical harmonic frequency determination. The electronic properties of S-H and C-S bonds in variously substituted thiophenols were analyzed using OP/TOP, QTAIM, and LVM methodologies. Computational processes, including conformational scans, geometry optimizations, and vibrational frequency calculations, were conducted using Gaussian 09, with ultra-fine integration grids and tight convergence criteria for the SCF procedure. Bond descriptors were computed utilizing ChemBOS, Multiwfn, and LModeA software, providing a robust and detailed examination of bond properties.

Glycerol as a partial replacement for lactose in milk replacer for young dairy calves.

Glycerol (glycerin) is increasingly available from biodiesel manufacture and edible oil refining and it has been used successfully in diets for chickens, pigs, and adult cattle; however, less information is available on its nutritional value in young calves. Our objective was to determine the effects on calf growth and health when glycerol replaced a portion of lactose in milk replacer. Holstein calves (12 male, 12 female) born at the University of Illinois dairy unit were assigned alternately to 1 of 2 treatments (24 calves total): control milk replacer or milk replacer supplemented with 15% glycerol in replacement of lactose. The experimental base milk replacer contained greater protein, fat, minerals, and vitamins so that when glycerol was added, the composition would be the same as that of the control, except that glycerol replaced some lactose. Calves were housed in individual hutches bedded with straw, and water was freely available. Starter was offered beginning on d 36. The amount of milk replacer offered was reduced by half on d 43, and calves were weaned at d 49. Calves were fed milk replacers twice daily from d 3 of life. Milk replacers contained 28% protein (all from whey proteins), 2.6% lysine, and 15% fat. Control milk replacer contained 40% lactose, and the glycerol milk replacer contained 25% lactose. Both replacers were reconstituted to 15% solids. Glycerol (liquid) was added to reconstituted base milk replacer at each feeding. During wk 1, milk replacers were fed at a rate of 0.25 Mcal/kg of metabolic body weight (BW) (about 1.5% of BW daily as powder, or approximately 675 g/d) and from wk 2 to 6 at 0.30 Mcal/kg of metabolic BW (about 2% of BW daily, or approximately 900 to 1,200 g/d). Measurements of BW and stature were made weekly through d 56. Calf BW and average daily gain through d 35 (0.66 vs. 0.65 kg/d for controls and glycerol, respectively) did not differ significantly between treatments. Stature measurements (withers height, body length, heart girth) and measures of health (fecal scores, medical treatments) did not differ between treatments. Under the conditions of this experiment, glycerol was an acceptable replacement for at least 37.5% of the total lactose in milk replacer (15% of the formula) if economically favorable.

The impact of a vaccine mandate and the COVID-19 pandemic on influenza vaccination uptake in Western Australian health care students.

Annual influenza vaccination of health care students and workers helps protect themselves and patients from influenza, which has a high disease burden during seasonal peaks in Australia. Health care students are an important cohort whose early attitudes and habits towards influenza vaccination may influence future behaviours. We explored the knowledge, attitudes, and behaviours towards influenza vaccination of health care students in two universities from 2018 to 2020 using convergent mixed methodology. We also assessed the impact of two external events - the introduction of mandatory influenza vaccination for select students in 2019, and the COVID-19 pandemic in 2020. We found a significant increase in self-reported vaccination uptake between 2018 (73.5%) and 2020 (89.6%), with the mandate and COVID-19 pandemic being likely drivers of increased uptake. Vaccine mandates are effective but must be supported by easy accessibility, adequately addressing concerns around effectiveness and safety, and promotion of voluntary acceptance and trust.

Nodal metastasis in endometrial cancer.

PURPOSE: Besides hysterectomy and bilateral salpingo-oophorectomy, the goal of surgery in early endometrial cancer is to identify extrauterine disease. The purpose of this study was to evaluate disease characteristics and survival of patients found to have nodal metastasis at staging for endometrial cancer. METHODS: All patients presenting to our practice from January 1993 to July 2009 with a new diagnosis of early endometrial cancer underwent pelvic and paraaortic lymph node sampling at the time of surgery as permitted by the body mass index. Patient and disease characteristics of patients with nodal metastasis were abstracted by retrospective chart review. Factors contributing to disease-free and overall corrected survival were evaluated. RESULTS: Forty-three patients with an early endometrial cancer were found to have pelvic and/or paraaortic nodal metastasis. Thirty-three percent of patients with nodal metastasis had papillary serous or clear cell cancers. Such tumors were often superficially invasive, yet were more likely to demonstrate lymphovascular space involvement as compared to endometrioid cancers. Furthermore, in a global model of disease-free and overall corrected survival, only tumor histology (endometrioid vs non-endometrioid) was a significant prognostic factor. Excluding clear cell and papillary serous tumors, only tumor grade was a significant prognostic factor in disease-free survival and overall corrected survival in patients with endometrioid adenocarcinomas and nodal involvement. Following adjuvant treatment after surgery, the recurrences were nearly evenly divided between pelvic, paraaortic nodal and distant sites. Only four of 33 (12%) patients treated with adjuvant pelvic radiation experienced a failure in the irradiated field. Furthermore, none of the patients experiencing a paraaortic nodal recurrence received adjuvant radiation to this site. CONCLUSIONS: The data suggest a benefit to the use of adjuvant radiation for local control of disease. Furthermore, the use of paclitaxel and carboplatinum chemotherapy also appears a promising adjunct in patients with endometrioid histologies and nodal spread. Papillary serous and clear cell cancers contributed disproportionately to the incidence of nodal metastasis and an adverse prognosis following further adjuvant therapy of patients with nodal disease. Despite taxol/carboplatinum chemotherapy, over half of the patients with non-endometrioid cancers recurred, as opposed to one of 19 endometrioid cancers so treated. The ideal form of adjuvant treatment for such patients remains problematic.

Improved oral intake after palliative duodenal stenting for malignant obstruction: a prospective multicenter clinical trial.

OBJECTIVES: We sought to test the hypothesis that placement of a new nitinol duodenal self-expandable metallic stent (SEMS) for palliation of malignant gastroduodenal obstruction is effective and safe in allowing patients to tolerate an oral diet. METHODS: In a prospective multicenter study, SEMSs (Duodenal WallFlex, Boston Scientific) were placed to alleviate gastroduodenal obstruction in inoperable patients without the ability to tolerate solid food. The primary study end point was improvement in oral intake monitored according to the 4-point Gastric Outlet Obstruction Scoring System (GOOSS) up to 24 weeks after stent placement. RESULTS: Forty-three patients received SEMSs, which were successfully deployed on the first attempt in 41 cases (95%) and the second attempt in two (5%). Within 1 day and 7 days after SEMS placement, 52% and 75% of patients, respectively, benefited from a GOOSS increase > or =1. Resumption of solid food intake (GOOSS 2-3) was attained by 56% of patients within 7 days and 80% by 28 days. Of the patients attaining GOOSS 2-3, 48% remained on solid food until death or last follow-up. Device-related adverse events included stent occlusion/malfunction in 9% of patients and perforation in 5% of patients. CONCLUSIONS: Duodenal WallFlex stent placement promptly improves oral intake in a majority of inoperable patients with malignant gastroduodenal obstruction. In approximately half the patients achieving GOOSS 2-3, the capacity for solid food intake endures until death or last follow-up.

Randomized clinical trial of folate supplementation in patients with peripheral arterial disease.

BACKGROUND: The aim was to determine whether folate supplementation improved arterial function in patients with peripheral arterial disease (PAD). METHODS: Individuals with PAD were randomly assigned to receive 400 microg folic acid (45 patients) or 5-methyltetrahydrofolate (5-MTHF) (48) daily, or placebo (40) for 16 weeks. Primary endpoints were changes in plasma total homocysteine (tHcy), ankle : brachial pressure index (ABPI) and pulse wave velocity (PWV). Secondary outcomes were changes in plasma inflammatory markers. RESULTS: Plasma tHcy was significantly reduced in folic acid and 5-MTHF groups compared with controls: median difference: - 2.12 (95 per cent confidence interval - 3.70 to - 0.75) micromol/l (P = 0.002) and - 2.07 (-3.48 to - 0.54) micromol/l (P = 0.007) respectively. ABPI improved significantly: median difference 0.07 (0.04 to 0.11) (P < 0.001) and 0.05 (0.01 to 0.10) (P = 0.009) respectively. Brachial-knee PWV (bk-PWV) decreased significantly in individuals receiving 5-MTHF and tended to be reduced in those taking folic acid compared with controls: median difference: - 1.10 (-2.20 to - 0.20) m/s (P = 0.011) and - 0.90 (-2.10 to 0.00) m/s (P = 0.051) respectively. Plasma levels of inflammatory markers were not affected. CONCLUSION: Folate administration reduced plasma homocysteine, and slightly improved ABPI and bk-PWV.

The urban homeless: estimating composition and size.

Although homelessness has been recognized as a serious and growing urban social problem, scientifically acceptable methods for estimating the composition and size of the homeless population have been lacking. A new research approach to estimating the size and composition of undomiciled urban populations is presented, and its utility is illustrated through a description of the literal homeless of Chicago. The homeless in the Chicago sample are unaffiliated persons living in extreme poverty, with high levels of physical and mental disability. Homelessness is interpreted as a manifestation of extreme poverty among persons without families in housing markets with declining stocks of inexpensive dwelling units suitable for single persons.

Comparative performance of uncoated, self-expanding metal biliary stents of different designs in 2 diameters: final results of an international multicenter, randomized, controlled trial.

BACKGROUND: The Wallstent has remained the industry standard for biliary self-expanding metal stents (SEMSs). Recently, stents of differing designs, compositions, and diameters have been developed. OBJECTIVE: To compare the new nitinol 6-mm and 10-mm Zilver stents with the 10-mm stainless steel Wallstent and determine the mechanism of obstruction. DESIGN: Randomized, prospective, controlled study. SETTING: Nine centers experienced in SEMS placement during ERCP. PATIENTS: A total of 241 patients presenting between September 2003 and December 2005 with unresectable malignant biliary strictures at least 2 cm distal to the bifurcation. MAIN OUTCOME MEASUREMENT: Stent occlusions requiring reintervention and death. RESULTS: At interim analysis, a significant increase in occlusions was noted in the 6-mm Zilver group at the P = .04 level, resulting in arm closure but continued follow-up. Final study arms were 64, 88, and 89 patients receiving a 6-mm Zilver, 10-mm Zilver, and 10-mm Wallstent, respectively. Stent occlusions occurred in 25 (39.1%) of the patients in the 6-mm Zilver arm, 21 (23.9%) of the patients in the 10-mm Zilver arm, and 19 (21.4%) of the patients in the 10-mm Wallstent arm (P = .02). The mean number of days of stent patency were 142.9, 185.8, and 186.7, respectively (P = .057). No differences were noted in secondary endpoints, and the study was ended at the 95% censored study endpoints. Biopsy specimens of ingrowth occlusive tissue revealed that 56% were caused by benign epithelial hyperplasia. CONCLUSIONS: SEMS occlusions were much more frequent with a 6-mm diameter SEMS and equivalent in the two 10-mm arms despite major differences in stent design, material, and expansion, suggesting that diameter is the critical feature. Malignant tumor ingrowth produced only a minority of the documented occlusions.

Incidence of benign inflammatory disease in patients undergoing Whipple procedure for clinically suspected carcinoma: a single-institution experience.

BACKGROUND: We evaluated the incidence of chronic pancreatitis and chronic bile duct inflammation in patients undergoing pancreaticoduodenectomy (PD) for suspected periampullary cancer. METHODS: Differences between clinical presentation, surgical management, and outcomes were compared between patients with malignancy and benign inflammatory disease. RESULTS: The incidence of chronic inflammatory disease was 12.9% (21/162). Patients with chronic inflammatory disease were associated with a higher incidence of smoking (75.0% versus 64.7%) and chronic alcohol use (66.7% versus 46.2%). Jaundice was significantly more frequent in patients with malignant disease (83.6% versus 42.9%, P < .05). Surgery for chronic inflammatory disease was associated with significantly more intraoperative bleeding (P < .05). CONCLUSIONS: The finding of chronic inflammatory disease after PD for suspected carcinoma is justifiable because (1) none of the available diagnostic modalities are infallible, (2) early treatment of pancreatic cancer is crucial for achieving cure, and (3) PD may relieve clinical symptoms in patients with chronic pancreatitis or pancreatic cancer.

Energy drink use is associated with alcohol and substance use in eighth, tenth, and twelfth graders.

The increasing prevalence of energy drink (ED) use and its link with negative behaviors and adverse health outcomes has garnered much attention. Use of EDs combined with alcohol among college students has been of particular interest. It is unclear if these relationships develop in the context of college, or if similar associations exist in younger individuals. The present study examined associations between ED consumption patterns and other substance use in an adolescent, school-based sample. Participants were N = 3743 students attending 8th, 10th or 12th grade in a suburban central Virginia public school system who completed a prevention needs assessment survey in 2012. Chi-square analyses and logistic regressions were used to compare rates of alcohol, tobacco and other drug use across three ED use groups: moderate/heavy (12.6%), light (30.5%), and non-users (57%). Over 40% of the sample reported recent (past month) ED use, with males more likely to report moderate/heavy ED use than females (14.0% and 11.1%, respectively; p = 0.02). After adjusting for gender and grade, ED use group predicted lifetime alcohol, tobacco and other drug use (all p < 0.001). Moderate/heavy ED users were most likely and ED non-users were least likely to report using each of the 13 substances in the survey, with light ED users intermediate to the other two groups. Moderate/heavy ED users were consistently most likely to report licit and illicit substance use. Additional research is needed to better understand which adolescents are at greatest risk for adverse health behaviors associated with ED use.

Rapid direct conversion of Cu(2-x)Se to CuAgSe nanoplatelets via ion exchange reactions at room temperature.

The use of template nanostructures for the creation of photovoltaic and thermoelectric semiconductors is becoming a quickly expanding synthesis strategy. In this work we report a simple two-step process enabling the formation of ternary CuAgSe nanoplatelets with a great degree of control over the composition and shape. Starting with hexagonal nanoplatelets of cubic Cu2-xSe, ternary CuAgSe nanoplatelets were generated through a rapid ion exchange reaction at 300 K using AgNO3 solution. The Cu2-xSe nanoplatelet template and the final CuAgSe nanoplatelets were analyzed by electron microscopy and X-ray diffraction (XRD). It was found that both the low temperature pseudotetragonal and the high temperature cubic forms of CuAgSe phase were created while maintaining the morphology of the Cu2-xSe nanoplatelet template. Thermal and electronic transport measurements of hot-pressed pellets of the synthesized CuAgSe nanoplatelets showed a drastic reduction in the thermal conductivity and a sharp transition from n-type (S = -45 µV K(-1)) to p-type (S = +200 µV K(-1)) semiconducting behavior upon heating above the structural transition from the low temperature orthorhombic to the high temperature super-ionic cubic phase. This simple reaction process utilizing a template nanostructure matrix represents an energy efficient, cost-efficient, and versatile strategy to create interesting materials with lower defect density and superior thermoelectric performance.

Amine accumulation in Parkinson's disease and other disorders.

Amine accumulation in the axons of degenerating, amine-containing neurones is a natural component of neurone death in many species, including man. While it is becoming increasingly clear that this phenomenon may have functional significance in animal models of Parkinson's Disease, its potential importance in the clinical syndrome has been pretermitted. There are several reasons for this. Failure to sample tissue which contains accumulated amines, the masking of accumulation by adjacent depleted tissues and the degradation of accumulated amines in post-mortem tissues from Parkinsonian brains could account for the low incidence of detection of accumulation in this disorder. Increased levels of amines have been detected in the brains of patients with other conditions including cerebral infarction, Alzheimer's Disease and Huntington's Chorea. These increases have been attributed previously to enhanced aminergic activity, rather than a stage in the degenerative process, as our hypothesis suggests. In addition to the potential importance of amine accumulation in the pathophysiology of various clinical syndromes, a more thorough investigation of this phenomenon in animal models would seem essential since they are used routinely to both describe the basic principles of dopamine function and to evaluate therapeutic possibilities in Parkinson's Disease.

Glomerular dynamics and morphology of aged spontaneously hypertensive rats. Effects of angiotensin-converting enzyme inhibition.

Relationships between glomerular dynamics and renal injury, micropuncture and histological studies were assessed in 73 week-old normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats divided into untreated and angiotension-converting enzyme inhibitor-treated (quinapril; 3 mg/kg/day; for 3 weeks) groups. Urinary protein excretion (UPE) and histologic arteriolar (AIS) and glomerular (GIS) injury scores were determined. Mean arterial pressure (MAP) of untreated SHR was increased compared with WKY (200 +/- 6 vs 119 +/- 4 mm Hg; P < 0.01), effective renal plasma flow (ERPF) was reduced (1.47 +/- 0.21 vs 3.06 +/- 0.26 ml/min/per g; P > 0.01), and filtration fraction (FF) and total renal vascular resistance (RVR) of SHR were increased (P < 0.01). Single-nephron plasma flow (SNPF) of untreated SHR was decreased (174 +/- 17 vs 80 +/- 9 ml/min; P < 0.01), and single-nephron filtration fraction and afferent arteriolar resistance (RA) were increased (19.4 +/- 1.8 vs 30.0 +/- 2.5% and 1.90 +/- 0.25 vs 9.05 +/- 1.35 U, respectively; both P < 0.01). Despite reduced SNPF, glomerular capillary pressure (PG) increased (49.7 +/- 0.7 vs 53.8 +/- 1.3 mm Hg; P < 0.05), the result of efferent arteriolar constriction (1.15 +/- 0.18 vs 2.84 +/- 0.36 U; P < 0.01). Untreated SHR had higher UPE (13.9 +/- 1.5 vs 42.8 +/- 3.2; mg/100 g per day; P < 0.01) and GIS and AIS scores than WKY (4.3 +/- 1.1 vs 64.3 +/- 8.4 and 16.6 +/- 3.1 vs 96.3 +/- 14.4; both P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Outpatient treatment of schizophrenia.

The authors discuss the treatment of 575 schizophrenic patients over the past 15 years. They describe a shift the patients have experiences from reliance on inpatient treatment to heavy use of outpatient services. The have found that effective outpatient treatment for these patients involves a program of nearly continuous administration of neuroleptic medication combined with counseling and social and crisis services. A major component of the outpatient management of these schizophrenic patients is the education of the patients in how to regulate their own medication within a prescribed range. This educational component appears to add a measure of precision that enhances the safety and reliability of the treatment program.

Proinflammatory cytokines regulate myogenic cell proliferation and fusion but have no impact on myotube protein metabolism or stress protein expression.

The objective of the present study was to evaluate the effect of the proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1-alpha (IL-1a), on myoblast proliferation and fusion and on myocyte protein metabolism and stress protein expression. Proliferation was suppressed (p < 0.05) by both cytokines, alone and in combination, and at lower concentrations, the suppression was additive. Likewise, fusion was retarded (p < 0.05) by these cytokines alone and in combination. Myosin synthesis was not altered acutely or chronically by TNF-alpha alone or by the combination of this cytokine with IL-1alpha. Chronic exposure to TNF-alpha did not alter total cellular protein synthesis, but exposure to IL-1alpha and the cytokine combination resulted in an increase (14% to 19%, p < 0.05) in synthesis. Neither total cellular protein nor myosin degradation were influenced by either cytokine alone or by the combination. There was no detectable induction, acutely or chronically, of any of the stress proteins evaluated (HSC70, HSP70, or HSP60). These data suggest that cytokines may alter muscle growth and development prenatally and postnatally and that the changes in muscle protein metabolism during periods of immune challenge are not direct effects of TNF-alpha or IL-1alpha.