Spectroscopic Investigation of the Activation of a Chromium-Pyrrolyl Ethene Trimerization Catalyst.

1-Hexene is an important α-olefin for polyethylene production and is produced from ethene. Recent developments in the α-olefin industry have led to the successful commercialization of ethene trimerization catalysts. An important industrially applied ethene trimerization system uses a mixture of chromium 2-ethylhexanoate, AlEt3, AlEt2Cl, and 2,5-dimethylpyrrole (DMP). Here, we have studied the activation of this system using catalytic and spectroscopic experiments (XAS, EPR, and UV-vis) under conditions employed in industry. First, chromium 2-ethylhexanoate was prepared and characterized to be [Cr3O(RCO2)6(H2O)3]Cl. Next, the activation of chromium 2-ethylhexanoate with AlEt3, AlEt2Cl, and DMP was studied, showing immediate reduction (<5 ms) of the trinuclear Cr(III) carboxylate and formation of a neutral polynuclear Cr(II) carboxylate complex. Over time, this Cr(II) carboxylate complex is partially converted into a chloro-bridged dinuclear Cr(II) pyrrolyl complex. In cyclohexane, small quantities of an unknown Cr(I) complex (∼1% after 1 h) are observed, while in toluene, the quantity of Cr(I) is much higher (∼23% after 1 h). This is due to the formation of cationic bis(tolyl)Cr(I) complexes, which likely leads to the observed inferior performance using toluene as the reaction solvent. Catalytic studies allow us to exclude some of the observed Cr(I) and Cr(II) complexes as the active species in this catalytic system. Using this combination of techniques, we have been able to structurally characterize complexes of this selective Cr-catalyzed trimerization system under conditions which are employed in industry.

CO oxidation over supported gold nanoparticles as revealed by operando grazing incidence X-ray scattering analysis.

The mechanism of carbon monoxide oxidation over gold was explored using a model planar catalyst consisting of monodisperse gold nanoparticles periodically arranged on single crystal SiO2/Si(111) substrates using a combination of Grazing Incidence Small Angle X-ray Scattering and Grazing Incidence X-ray Diffraction (GISAXS/GIXD) under reaction conditions. It is shown that nanoparticle composition, size and shape change when the catalyst is exposed to reactive gases. During CO oxidation, the particle's submergence depth with respect to the surface decreases due to the removal of gold oxide at the metal-support edge, meanwhile the particle 'flattens' to maximise the number of the reaction sites along its perimeter. The effect of the CO concentration on the catalyst structure is also discussed. Our results support the dual catalytic sites mechanism whereby CO is activated on the gold surface whereas molecular oxygen is dissociating at the gold-support interface.

Universal 2 total wrist arthroplasty: high satisfaction but high complication rates.

The Universal 2 total wrist arthroplasty is intended to alleviate wrist pain and restore function. There is limited evidence regarding its success and safety. We report outcomes in 48 wrists of 46 patients with Universal 2 arthroplasty between 2006 and 2014. We recorded range of motion of the operated wrist, patient satisfaction, complication and revision rates, and radiological appearances of the wrists with mean follow-up of 7 years (3.5 to 11 years). We found a significant improvement in DASH scores after surgery, with active range of wrist motion being 33° flexion and 24° extension. Thirty-nine patients would undergo the procedure again if he had similar wrist problems. Twenty-three patients had loosening of at least one component of the implant. Complications were found in 13 wrists; seven underwent revision. We conclude that the Universal 2 arthroplasty produces significant improvements in DASH scores and high levels of satisfaction of the patients. However, the surgery has a high complication rate. LEVEL OF EVIDENCE: IV.

Hemodialysis treatment engenders anxiety and emotional distress
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AIMS: Anxiety is common in maintenance hemodialysis (MHD) patients. The extent to which anxiety is engendered by the dialysis treatment itself is not known. We investigated whether anxiety occurs with individual hemodialysis treatments and examined factors associated with these symptoms. MATERIALS AND METHODS: This was a cross-sectional study examining 246 MHD patients. Anxiety and other emotional distresses associated with hemodialysis treatments were examined with a questionnaire. Patients were also assessed with the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). RESULTS: Patients were 57 ± 15 (SD) years; 58% male, 46% diabetic, and undergoing MHD for a median of 40 months (range: 6 - 210 months). 32 - 51% of patients reported anxiety when coming to dialysis, hearing an alarm sound, being connected to the dialysis machine by a new person or seeing paramedics in the dialysis unit. 12 - 18% of patients experienced severe anxiety with one or more of these events. Dialysis-related anxiety correlated with severity of anxiety and depression as determined by BAI and BDI (p < 0.0001 for each comparison) but generally not with dialysis vintage. Even among patients with no or minimal anxiety according to BAI, 9 - 23% reported a little bit to moderate anxiety and 9 - 15% described quite a bit to extreme anxiety with hemodialysis treatments. The frequency that patients described distressing thoughts and feelings correlated directly with their degree of anxiety or depression as determined by BAI and BDI. CONCLUSION: Patients commonly experience anxiety, which is often severe, with MHD treatments. Hemodialysis-induced anxiety is directed related to the presence and severity of underlying anxiety and depression. Hemodialysis-associated anxiety is prevalent and may be severe even in patients with minimal or no anxiety and/or depression, as determined by BAI and BDI. The frequency and severity of hemodialysis anxiety does not decrease with greater dialysis vintage except for a reduction in anxiety when hearing the dialysis machine alarm.
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Transient Formation and Reactivity of a High-Valent Nickel(IV) Oxido Complex.

A reactive high-valent dinuclear nickel(IV) oxido bridged complex is reported that can be formed at room temperature by reaction of [(L)2Ni(II)2(µ-X)3]X (X = Cl or Br) with NaOCl in methanol or acetonitrile (where L = 1,4,7-trimethyl-1,4,7-triazacyclononane). The unusual Ni(IV) oxido species is stabilized within a dinuclear tris-µ-oxido-bridged structure as [(L)2Ni(IV)2(µ-O)3]2+. Its structure and its reactivity with organic substrates are demonstrated through a combination of UV-vis absorption, resonance Raman, 1H NMR, EPR, and X-ray absorption (near-edge) spectroscopy, ESI mass spectrometry, and DFT methods. The identification of a Ni(IV)-O species opens opportunities to control the reactivity of NaOCl for selective oxidations.

Chemical imaging of Fischer-Tropsch catalysts under operating conditions.

Although we often understand empirically what constitutes an active catalyst, there is still much to be understood fundamentally about how catalytic performance is influenced by formulation. Catalysts are often designed to have a microstructure and nanostructure that can influence performance but that is rarely considered when correlating structure with function. Fischer-Tropsch synthesis (FTS) is a well-known and potentially sustainable technology for converting synthetic natural gas ("syngas": CO + H2) into functional hydrocarbons, such as sulfur- and aromatic-free fuel and high-value wax products. FTS catalysts typically contain Co or Fe nanoparticles, which are often optimized in terms of size/composition for a particular catalytic performance. We use a novel, "multimodal" tomographic approach to studying active Co-based catalysts under operando conditions, revealing how a simple parameter, such as the order of addition of metal precursors and promoters, affects the spatial distribution of the elements as well as their physicochemical properties, that is, crystalline phase and crystallite size during catalyst activation and operation. We show in particular how the order of addition affects the crystallinity of the TiO2 anatase phase, which in turn leads to the formation of highly intergrown cubic close-packed/hexagonal close-packed Co nanoparticles that are very reactive, exhibiting high CO conversion. This work highlights the importance of operando microtomography to understand the evolution of chemical species and their spatial distribution before any concrete understanding of impact on catalytic performance can be realized.

Predictors of weight loss 2 years after laparoscopic sleeve gastrectomy.

INTRODUCTION: Despite the rapidly increasing popularity of laparoscopic sleeve gastrectomy (LSG), there is limited data examining weight loss more than 1 year after the procedure. There have also been few studies examining baseline predictors of weight loss after LSG. We aimed to examine the percentage of excess weight loss (%EWL) in patients 2 years after LSG and identify baseline predictors of %EWL. METHODS: Electronic records from university hospitals were available for 292 patients who underwent LSG (205 women; mean age, 41.5 ± 11.1 years; mean weight, 126.5 ± 27.5 kg; mean BMI, 45.5 ± 7.5 kg/m(2) ). Variables assessed for predictive effect were baseline age, sex, BMI, presence of comorbidities (diabetes, hypertension, or obstructive sleep apnea), the amount of weight loss induced by a very low-calorie diet before surgery, and the number of clinic appointments attended over the 2 years. We performed linear regression and mixed model analyses between predictor variables and %EWL at 2 years. RESULTS: Adjusted %EWL was 31% at 2 weeks, 49% at 3 months, 64% at 6 months, 70% at 9 months, 76% at 12 months, 79% at 18 months, and 79% at 2 years. Multivariate analysis showed that lower baseline BMI, absence of hypertension, and greater clinic attendance predicted better %EWL (r(2) = 0.11). CONCLUSION: Longer-term follow-up studies of weight loss post LSG are required to assist with patient care and management.

The efficacy of bariatric surgery performed in the public sector for obese patients with comorbid conditions.

OBJECTIVE: To determine the efficacy of bariatric surgery in the public sector for the treatment of complicated obesity. DESIGN, SETTING AND PARTICIPANTS: A longitudinal observational study of obese participants with comorbid conditions, aged 21-73 years, who underwent publicly funded bariatric surgery. Data were extracted from clinical databases (1 October 2009 to 1 September 2013) and recorded at seven time points. Participants are from an ongoing public obesity program. MAIN OUTCOME MEASURES: Postoperative weight loss and partial or full resolution of: type 2 diabetes mellitus (T2DM), hypertension (HTN), dyslipidaemia and obstructive sleep apnoea (OSA). RESULTS: The 65 participants in the cohort lost a mean weight of 22.6 kg (SD, 9.5 kg) by 3 months, 34.2.kg (SD, 20.1 kg) by 12 months and 39.9 kg (SD, 31.4 kg) by 24 months (P < 0.001). Body mass index (BMI) decreased from a preoperative mean of 48.2 kg/m(2) (SD, 9.5 kg/m(2)) to 35.7 kg/m(2) (SD, 7.7 kg/m(2)) by 24 months (P < 0.001). Full resolution of comorbid conditions by 18 months (P < 0.001) was achieved by almost half of those with baseline T2DM, nearly two-thirds with HTN and three-quarters of those with OSA, with continued improvements beyond 24 months. CONCLUSIONS: Bariatric surgery performed in the public sector is efficacious in the treatment of obese patients with comorbid conditions. Our findings parallel similar studies suggesting that there is equal benefit in publicly funded and privately performed procedures. This study highlights that obese patients reliant on public health care maintain sufficient intrinsic motivation in the absence of payment and supposed value-driven incentive. Improved access to bariatric surgery in the public sector can justifiably reduce the health inequities for those most in need.

Surgical versus endoscopic treatment of bile duct stones.

BACKGROUND: Between 10% to 18% of people undergoing cholecystectomy for gallstones have common bile duct stones. Treatment of the bile duct stones can be conducted as open cholecystectomy plus open common bile duct exploration or laparoscopic cholecystectomy plus laparoscopic common bile duct exploration (LC + LCBDE) versus pre- or post-cholecystectomy endoscopic retrograde cholangiopancreatography (ERCP) in two stages, usually combined with either sphincterotomy (commonest) or sphincteroplasty (papillary dilatation) for common bile duct clearance. The benefits and harms of the different approaches are not known. OBJECTIVES: We aimed to systematically review the benefits and harms of different approaches to the management of common bile duct stones. SEARCH METHODS: We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL, Issue 7 of 12, 2013) in The Cochrane Library, MEDLINE (1946 to August 2013), EMBASE (1974 to August 2013), and Science Citation Index Expanded (1900 to August 2013). SELECTION CRITERIA: We included all randomised clinical trials which compared the results from open surgery versus endoscopic clearance and laparoscopic surgery versus endoscopic clearance for common bile duct stones. DATA COLLECTION AND ANALYSIS: Two review authors independently identified the trials for inclusion and independently extracted data. We calculated the odds ratio (OR) or mean difference (MD) with 95% confidence interval (CI) using both fixed-effect and random-effects models meta-analyses, performed with Review Manager 5. MAIN RESULTS: Sixteen randomised clinical trials with a total of 1758 randomised participants fulfilled the inclusion criteria of this review. Eight trials with 737 participants compared open surgical clearance with ERCP; five trials with 621 participants compared laparoscopic clearance with pre-operative ERCP; and two trials with 166 participants compared laparoscopic clearance with postoperative ERCP. One trial with 234 participants compared LCBDE with intra-operative ERCP. There were no trials of open or LCBDE versus ERCP in people without an intact gallbladder. All trials had a high risk of bias.There was no significant difference in the mortality between open surgery versus ERCP clearance (eight trials; 733 participants; 5/371 (1%) versus 10/358 (3%) OR 0.51;95% CI 0.18 to 1.44). Neither was there a significant difference in the morbidity between open surgery versus ERCP clearance (eight trials; 733 participants; 76/371 (20%) versus 67/358 (19%) OR 1.12; 95% CI 0.77 to 1.62). Participants in the open surgery group had significantly fewer retained stones compared with the ERCP group (seven trials; 609 participants; 20/313 (6%) versus 47/296 (16%) OR 0.36; 95% CI 0.21 to 0.62), P = 0.0002.There was no significant difference in the mortality between LC + LCBDE versus pre-operative ERCP +LC (five trials; 580 participants; 2/285 (0.7%) versus 3/295 (1%) OR 0.72; 95% CI 0.12 to 4.33). Neither was there was a significant difference in the morbidity between the two groups (five trials; 580 participants; 44/285 (15%) versus 37/295 (13%) OR 1.28; 95% CI 0.80 to 2.05). There was no significant difference between the two groups in the number of participants with retained stones (five trials; 580 participants; 24/285 (8%) versus 31/295 (11%) OR 0.79; 95% CI 0.45 to 1.39).There was only one trial assessing LC + LCBDE versus LC+intra-operative ERCP including 234 participants. There was no reported mortality in either of the groups. There was no significant difference in the morbidity, retained stones, procedure failure rates between the two intervention groups.Two trials assessed LC + LCBDE versus LC+post-operative ERCP. There was no reported mortality in either of the groups. There was no significant difference in the morbidity between laparoscopic surgery and postoperative ERCP groups (two trials; 166 participants; 13/81 (16%) versus 12/85 (14%) OR 1.16; 95% CI 0.50 to 2.72). There was a significant difference in the retained stones between laparoscopic surgery and postoperative ERCP groups (two trials; 166 participants; 7/81 (9%) versus 21/85 (25%) OR 0.28; 95% CI 0.11 to 0.72; P = 0.008.In total, seven trials including 746 participants compared single staged LC + LCBDE versus two-staged pre-operative ERCP + LC or LC + post-operative ERCP. There was no significant difference in the mortality between single and two-stage management (seven trials; 746 participants; 2/366 versus 3/380 OR 0.72; 95% CI 0.12 to 4.33). There was no a significant difference in the morbidity (seven trials; 746 participants; 57/366 (16%) versus 49/380 (13%) OR 1.25; 95% CI 0.83 to 1.89). There were significantly fewer retained stones in the single-stage group (31/366 participants; 8%) compared with the two-stage group (52/380 participants; 14%), but the difference was not statistically significantOR 0.59; 95% CI 0.37 to 0.94).There was no significant difference in the conversion rates of LCBDE to open surgery when compared with pre-operative, intra-operative, and postoperative ERCP groups. Meta-analysis of the outcomes duration of hospital stay, quality of life, and cost of the procedures could not be performed due to lack of data. AUTHORS' CONCLUSIONS: Open bile duct surgery seems superior to ERCP in achieving common bile duct stone clearance based on the evidence available from the early endoscopy era. There is no significant difference in the mortality and morbidity between laparoscopic bile duct clearance and the endoscopic options. There is no significant reduction in the number of retained stones and failure rates in the laparoscopy groups compared with the pre-operative and intra-operative ERCP groups. There is no significant difference in the mortality, morbidity, retained stones, and failure rates between the single-stage laparoscopic bile duct clearance and two-stage endoscopic management. More randomised clinical trials without risks of systematic and random errors are necessary to confirm these findings.

Surgical versus endoscopic treatment of bile duct stones.

BACKGROUND: Between 10% to 18% of people undergoing cholecystectomy for gallstones have common bile duct stones. Treatment of the bile duct stones can be conducted as open cholecystectomy plus open common bile duct exploration or laparoscopic cholecystectomy plus laparoscopic common bile duct exploration (LC + LCBDE) versus pre- or post-cholecystectomy endoscopic retrograde cholangiopancreatography (ERCP) in two stages, usually combined with either sphincterotomy (commonest) or sphincteroplasty (papillary dilatation) for common bile duct clearance. The benefits and harms of the different approaches are not known. OBJECTIVES: We aimed to systematically review the benefits and harms of different approaches to the management of common bile duct stones. SEARCH METHODS: We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL, Issue 7 of 12, 2013) in The Cochrane Library, MEDLINE (1946 to August 2013), EMBASE (1974 to August 2013), and Science Citation Index Expanded (1900 to August 2013). SELECTION CRITERIA: We included all randomised clinical trials which compared the results from open surgery versus endoscopic clearance and laparoscopic surgery versus endoscopic clearance for common bile duct stones. DATA COLLECTION AND ANALYSIS: Two review authors independently identified the trials for inclusion and independently extracted data. We calculated the odds ratio (OR) or mean difference (MD) with 95% confidence interval (CI) using both fixed-effect and random-effects models meta-analyses, performed with Review Manager 5. MAIN RESULTS: Sixteen randomised clinical trials with a total of 1758 randomised participants fulfilled the inclusion criteria of this review. Eight trials with 737 participants compared open surgical clearance with ERCP; five trials with 621 participants compared laparoscopic clearance with pre-operative ERCP; and two trials with 166 participants compared laparoscopic clearance with postoperative ERCP. One trial with 234 participants compared LCBDE with intra-operative ERCP. There were no trials of open or LCBDE versus ERCP in people without an intact gallbladder. All trials had a high risk of bias.There was no significant difference in the mortality between open surgery versus ERCP clearance (eight trials; 733 participants; 5/371 (1%) versus 10/358 (3%) OR 0.51;95% CI 0.18 to 1.44). Neither was there a significant difference in the morbidity between open surgery versus ERCP clearance (eight trials; 733 participants; 76/371 (20%) versus 67/358 (19%) OR 1.12; 95% CI 0.77 to 1.62). Participants in the open surgery group had significantly fewer retained stones compared with the ERCP group (seven trials; 609 participants; 20/313 (6%) versus 47/296 (16%) OR 0.36; 95% CI 0.21 to 0.62), P = 0.0002.There was no significant difference in the mortality between LC + LCBDE versus pre-operative ERCP +LC (five trials; 580 participants; 2/285 (0.7%) versus 3/295 (1%) OR 0.72; 95% CI 0.12 to 4.33). Neither was there was a significant difference in the morbidity between the two groups (five trials; 580 participants; 44/285 (15%) versus 37/295 (13%) OR 1.28; 95% CI 0.80 to 2.05). There was no significant difference between the two groups in the number of participants with retained stones (five trials; 580 participants; 24/285 (8%) versus 31/295 (11%) OR 0.79; 95% CI 0.45 to 1.39).There was only one trial assessing LC + LCBDE versus LC+intra-operative ERCP including 234 participants. There was no reported mortality in either of the groups. There was no significant difference in the morbidity, retained stones, procedure failure rates between the two intervention groups.Two trials assessed LC + LCBDE versus LC+post-operative ERCP. There was no reported mortality in either of the groups. There was no significant difference in the morbidity between laparoscopic surgery and postoperative ERCP groups (two trials; 166 participants; 13/81 (16%) versus 12/85 (14%) OR 1.16; 95% CI 0.50 to 2.72). There was a significant difference in the retained stones between laparoscopic surgery and postoperative ERCP groups (two trials; 166 participants; 7/81 (9%) versus 21/85 (25%) OR 0.28; 95% CI 0.11 to 0.72; P = 0.008.In total, seven trials including 746 participants compared single staged LC + LCBDE versus two-staged pre-operative ERCP + LC or LC + post-operative ERCP. There was no significant difference in the mortality between single and two-stage management (seven trials; 746 participants; 2/366 versus 3/380 OR 0.72; 95% CI 0.12 to 4.33). There was no a significant difference in the morbidity (seven trials; 746 participants; 57/366 (16%) versus 49/380 (13%) OR 1.25; 95% CI 0.83 to 1.89). There were significantly fewer retained stones in the single-stage group (31/366 participants; 8%) compared with the two-stage group (52/380 participants; 14%), but the difference was not statistically significantOR 0.59; 95% CI 0.37 to 0.94).There was no significant difference in the conversion rates of LCBDE to open surgery when compared with pre-operative, intra-operative, and postoperative ERCP groups. Meta-analysis of the outcomes duration of hospital stay, quality of life, and cost of the procedures could not be performed due to lack of data. AUTHORS' CONCLUSIONS: Open bile duct surgery seems superior to ERCP in achieving common bile duct stone clearance based on the evidence available from the early endoscopy era. There is no significant difference in the mortality and morbidity between laparoscopic bile duct clearance and the endoscopic options. There is no significant reduction in the number of retained stones and failure rates in the laparoscopy groups compared with the pre-operative and intra-operative ERCP groups. There is no significant difference in the mortality, morbidity, retained stones, and failure rates between the single-stage laparoscopic bile duct clearance and two-stage endoscopic management. More randomised clinical trials without risks of systematic and random errors are necessary to confirm these findings.

Helping people with HIV/AIDS return to work: a randomized clinical trial.

OBJECTIVE: New treatments introduced in the mid-1990s led many people with HIV/AIDS who previously had been disabled by their disease to contemplate workforce reentry; many remain unemployed, and little is known concerning interventions that might help them return to work. We report the results of a randomized clinical trial of an intervention designed to help people with HIV/AIDS reenter the workforce. DESIGN: We tested a mixed (group-individual) modality intervention that incorporated elements of Motivational Interviewing (Miller & Rollnick, 2002), skills building from Dialectical Behavior Therapy (Linehan, 1993), and job-related skills (Price & Vinokur, 1995). A total of 174 individuals participated in either the intervention or in standard of care and were followed for 24 months. RESULTS: Compared with individuals referred for standard of care, participants in the intervention engaged in more workforce-reentry activities over time and, once employed, were more likely to remain employed. Dose-response analyses revealed that among intervention participants, participants who attended more than 1 individual session engaged in more workforce-reentry activities than individuals who attended 1 or fewer individual sessions, whereas frequency of group session participation did not effect a difference between participants who attended more than 6 group sessions and participants who attended 6 or fewer group sessions. CONCLUSION: Theoretically based workforce-reentry assistance programs can assist disabled people with HIV/AIDS in their return-to-work efforts.

Pancreatic surgery: beyond the traditional limits.

Pancreatic cancer is one of the five leading causes of cancer death for both males and females in the western world. More than 85 % pancreatic tumors are of ductal origin but the incidence of cystic tumors such as intrapapillary mucinous tumors (IPMN) or mucinous cystic tumors (MCN) and other rare tumors is rising. Complete surgical resection of the tumor is the mainstay of any curative therapeutic approach, however, up to 40 % of patients with potentially resectable pancreatic cancer are not offered surgery. This is despite 5-year survival rates of up to 40 % or even higher in selected patients depending on tumor stage and histology. Standard procedures for pancreatic tumors include the Kausch-Whipple- or pylorus-preserving Whipple procedure, and the left lateral pancreatic resection (often with splenectomy), and usually include regional lymphadenectomy. More radical or extended pancreatic operations are becoming increasingly utilised however and we examine the data available for their role. These operations include major venous and arterial resection, multivisceral resections and surgery for metastatic disease, or palliative pancreatic resection. Portal vein resection for local infiltration with or without replacement graft is now well established and does not deleteriously affect perioperative morbidity or mortality. Arterial resection, however, though often technically feasible, has questionable oncologic impact, is not without risk and is usually reserved for isolated cases. The value of extended lymphadenectomy is frequently debated; the recent level I evidence demonstrates no advantage. Multivisceral resections, i.e. tumors, often in the tail of the pancreas, with invasion of the colon or stomach or other surrounding tissues, while associated with an increased morbidity and a longer hospital stay, do however show comparable mortality-and survival rates to those without such infiltration and therefore should be performed if technically feasible. Routine resection for metastatic disease however does not seem to show any advantage over palliative treatment but may be an option in selected patients with easily removable metastases. In conclusion pancreatic surgery beyond the traditional limits is established in tumors infiltration the venous system and may be a considered approach in selected patients with locally infiltrating pancreatic cancer or metastasis.

Renal tumors and second primary pancreatic tumors: a relationship with clinical impact?

BACKGROUND: The occurrence of synchronous or metachronous renal cell carcinoma and pancreatic tumors has been described only in a few cases in the scientific literature. The study of double primary cancers is important because it might provide understanding of a shared genetic basis of different solid tumors and to detect patients at risk for secondary malignancy. METHODS: In a combined analysis of patient registries from University Departments of Urology and Visceral Surgery, 1178 patients with pancreatic tumors and 518 patients with renal cell carcinoma treated between 2001 and 2008 were evaluated, RESULTS: Overall 16 patients with renal cancer and synchronous (n = 6) or metachronous (n = 10) primary pancreatic tumors were detected. The median survival of all patients was 12.6 months, for the patients with synchronous resections 25.7 months and for the patients with metachronous resections 12.2 months, respectively. CONCLUSIONS: The association between these two etiologies of malignancy demands more detailed epidemiological and molecular investigation. Clinical outcomes would support a resection as a recommended clinically valid option.

An efficient synthesis of 3-OBn-6ß,14-epoxy-bridged opiates from naltrexone and identification of a related dual MOR inverse agonist/KOR agonist.

In an effort to better understand the conformational preferences that inform the biological activity of naltrexone and related naltrexol derivatives, a new synthesis of the restricted analog 3-OBn-6ß,14-epoxymorphinan 4 is described. 4 was synthesized starting from naltrexone in 50% overall yield, proceeding through the OBn-6α-triflate intermediate 8. Key steps to the synthesis include benzylation (96% yield), reduction (90% yield, α:ß:3:2), followed by a one-pot triflation/displacement sequence (96% yield) to yield the desired bridged epoxy derivative 4. X-ray crystallographic analysis of intermediate 3-OBn-6α-naltrexol 7a supports population of the key boat conformation required for the epoxy ring closure. We also report that the 6ß-mesylate 10-a high affinity opioid receptor ligand, the epimeric derivative of 11, and an analog of 12-functions as an inverse agonist at the mu opioid receptor using herkinorin pre-conditioned cells and an agonist at the kappa opioid receptor when evaluated in independent in vitro [(35)S]-GTP-γ-S assays.

Quality-of-life and mortality in hemodialysis patients: roles of race and nutritional status.

BACKGROUND AND OBJECTIVES: Maintenance hemodialysis (MHD) patients often have protein-energy wasting, poor health-related quality of life (QoL), and high premature death rates, whereas African-American MHD patients have greater survival than non-African-American patients. We hypothesized that poor QoL scores and their nutritional correlates have a bearing on racial survival disparities of MHD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We examined associations between baseline self-administered SF36 questionnaire-derived QoL scores with nutritional markers by multivariate linear regression and with survival by Cox models and cubic splines in the 6-year cohort of 705 MHD patients, including 223 African Americans. RESULTS: Worse SF36 mental and physical health scores were associated with lower serum albumin and creatinine levels but higher total body fat percentage. Spline analyses confirmed mortality predictability of worse QoL, with an almost strictly linear association for mental health score in African Americans, although the race-QoL interaction was not statistically significant. In fully adjusted analyses, the mental health score showed a more robust and linear association with mortality than the physical health score in all MHD patients and both races: death hazard ratios for (95% confidence interval) each 10 unit lower mental health score were 1.12 (1.05-1.19) and 1.10 (1.03-1.18) for all and African American patients, respectively. CONCLUSIONS: MHD patients with higher percentage body fat or lower serum albumin or creatinine concentration perceive a poorer QoL. Poor mental health in all and poor physical health in non-African American patients correlate with mortality. Improving QoL by interventions that can improve the nutritional status without increasing body fat warrants clinical trials.

On the road to single-site laparoscopic adjustable gastric banding: lessons learned from 60 cases.

BACKGROUND: Single-site laparoscopic surgery is a promising emerging technique with potential to decrease postoperative pain, reduce port-site complications, and improve cosmetic results. Laparoscopic adjustable gastric banding (LapGB) is a procedure that lends itself well to single-site laparoscopic surgery because the surgery is confined to a single region of the body, the need for a larger incision for port implantation and the fact that bariartric patients are more likely to be body image conscious. The procedure is, however, technically challenging and potentially more time consuming and hazardous. To simplify learning, a hybrid technique that used multiple conventional trocars and laparoscopic equipment through a single periumbilical incision while retaining the use of the Nathanson retractor via a separate epigastric incision was developed. The authors' experience and results with this technique are described. METHODS: This retrospective review describes the prospectively collected data for the first 60 consecutive cases completed using the minimally invasive technique described. RESULTS: The 60 cases in this study comprised 12 men and 48 women with an average age of 39 years (range 20-59 years). Their average body mass index (BMI) was 39.1 kg/m(2) (range 32-52 kg/m(2)). Four patients (6.7%) needed an additional port either for hemostasis or for access difficulties. Concomitant hiatal hernia repair was performed for 13 patients. Five patients (8.3%) had superficial wound infection requiring oral antibiotic therapy and dressings. No other complications were observed. Overall, the average operating time was 55 min (range 30-160 min). For both surgeons, the learning curve was six cases, with a significant difference in the operating times between the first six cases and the remaining cases (p < 0.0001, Mann-Whitney U test). CONCLUSIONS: The authors' early experience with the minimally invasive LapGB technique shows that it is feasible and safe. It can be used either as a bridging technique to single-site LapGB or on its own as a minimally invasive technique.

Neuropsychological functioning as a predictor of employment activity in a longitudinal study of HIV-infected adults contemplating workforce reentry.

Cognitive deficits are associated with HIV disease, and HIV-related cognitive deficits have been associated with declines in everyday functioning and vocational status. We administered a baseline neuropsychological (NP) test battery designed to assess estimated full-scale IQ, achievement, attention/concentration, executive function, language, mental speed, motor function, nonverbal memory, verbal memory, and visual-spatial function to a sample of 174 disabled, HIV-positive individuals enrolled in a randomized, controlled trial of a vocational-rehabilitation program. We then used these NP scores to predict employment at the end of participants' study participation, using both hierarchical multiple regression and ordinal logistic regression models. The hierarchical multiple regression analyses did not predict participants' employment activities at the end of study participation. In the ordinal logistic regression model, executive functioning weakly predicted employment status at the end of study participation and inspection of the predicted classifications revealed that 63% of the participants were incorrectly classified using this model. These results suggest that although predicting workforce reentry from NP testing may be statistically significant, NP testing may be of limited clinical value for informing the workforce reentry of disabled people with HIV who are interested in returning to work.

Vascular resection in pancreatic cancer surgery: survival determinants.

INTRODUCTION: Pancreaticoduodenectomy (PD) is the standard operation for cancer of the pancreatic head. To achieve complete tumor resection and, thus, improve long-term survival, venous resection of the portal or superior mesenteric vein with reconstruction has become routine for advanced pancreatic adenocarcinoma (PDAC). However, its clinical benefit still remains controversial. The aim of this study was to investigate morbidity, mortality, and survival of patients with advanced PDAC following PD with venous resection and to identify significant survival determinants. MATERIAL AND METHODS: From October 2001 to December 2007, 488 patients with PDAC of the pancreatic head underwent PD at our department. Venous resection was performed in 110 patients (22.5%). Clinical data, surgical techniques, perioperative parameters, and histopathologic data were analyzed on a prospective database. RESULTS: Major venous reconstruction was accomplished through primary lateral venorrhaphy in 18 patients (16.3%), polytetrafluoroethylene grafting (n = 14, 12.7%), primary end-to-end anastomosis (n = 72, 65.5%), an autologous saphenous venous graft patch (n = 4, 4.6%) or a Goretex(R) patch (n = 2, 2.3%). In 78.1% histopathologic examination revealed cancer invasion of the vein, whereas the remainder had peritumoral inflammation extending to the vessel wall. Perioperative morbidity rate was 41.8%; and the mortality rate 3.6%. The 1-, 2-, and 3-year survival rates were 55.2%, 23.1%, and 14.4%, respectively. Operating time (>420 min) and advanced age (>70 years) were the only prognostic variables, which significantly diminished survival on multivariate analysis. CONCLUSION: Resection of the superior mesenteric or portal vein to achieve macroscopic tumor clearance can be performed safely with acceptable operative morbidity and mortality. However, improved local clearance in these patients cannot achieve a favorable long-term survival for all patients because distant metastases or local recurrence is frequent.

Examination of the impact of ethnicity on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Fake Bad Scale.

The Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Fake Bad Scale (FBS; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) has been shown to be sensitive to somatic over-endorsement. However, the impact of ethnicity has not been examined on the FBS, which is of concern given some studies that show increased rates of somatic endorsement in particular ethnic groups. We evaluated the FBS performance of 190 Caucasian American, Hispanic, and African American outpatients who were obtained from two different clinical settings, excluding those who were applying for disability or in litigation. We failed to find significant ethnic differences in mean FBS performance or in cut-off specificity rates. We did find evidence of a gender effect, supporting continued use of gender-specific FBS cutoffs.

Long-term outcomes after laparoscopic bile duct exploration: a 5-year follow up of 150 consecutive patients.

BACKGROUND: The treatment of common bile duct stones discovered at routine intraoperative cholangiography includes postoperative endoscopic retrograde cholangiography or intraoperative laparoscopic common bile duct exploration. Given the equivalence of short-term outcome data for these two techniques, the choice of one over the other may be influenced by long-term follow-up data. We aimed to establish the long-term outcomes following laparoscopic common bile duct exploration and compare this with endoscopic retrograde cholangiography. METHODS: One hundred and fifty consecutive patients underwent laparoscopic common bile duct exploration between March 1998 and March 2006 carried out by a single surgeon. All were prospectively studied for 1 month followed by a late-term phone questionnaire ascertaining the prevalence of adverse symptoms. Patients presented with a standardized series of questions, with reports of symptoms corroborated by review of medical records. RESULTS: In 150 patients, operations included laparoscopic transcystic exploration (135), choledochotomy (10) and choledochoduodenostomy (2). At long-term follow up (mean 63 months), 116 (77.3%) patients were traceable, with 24 (20.7%) reporting an episode of pain and 18 (15.5%) had more than a single episode of pain. There was no long-term evidence of cholangitis, stricture or pancreatitis identified in any patient. CONCLUSION: Laparoscopic bile duct exploration appears not to increase the incidence of long-term adverse sequelae beyond the reported prevalence of postcholecystectomy symptoms. There was no incidence of bile duct stricture, cholangitis or pancreatitis. It is a safe procedure, which obviates the need and expense of preoperative or postoperative endoscopic retrograde cholangiography in most instances.