Antimicrobial activity of nature-inspired molecules against multidrug-resistant bacteria

Multidrug-resistant bacterial infections present a serious challenge to global health. In addition to the spread of antibiotic resistance, some bacteria can form persister cells which are tolerant to most antibiotics and can lead to treatment failure or relapse. In the present work, we report the discovery of a new class of small molecules with potent antimicrobial activity against Gram-positive bacteria and moderate activity against Gram-negative drug-resistant bacterial pathogens. The lead compound SIMR 2404 had a minimal inhibitory concentration (MIC) of 2 μg/mL against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-intermediate Staphylococcus aureus (VISA). The MIC values against Gram-negative bacteria such as Escherichia coli and Actinobacteria baumannii were between 8-32 μg/mL. Time-kill experiments show that compound SIMR 2404 can rapidly kill tested bacteria. Compound SIMR 2404 was also found to rapidly kill MRSA persisters which display high levels of tolerance to conventional antibiotics. In antibiotic evolution experiments, MRSA quickly developed resistance to ciprofloxacin but failed to develop resistance to compound SIMR 2404 even after 24 serial passages. Compound SIMR 2404 was not toxic to normal human fibroblast at a concentration of 4 μg/mL which is twice the MIC concentration against MRSA. However, at a concentration of 8 μg/mL or higher, it showed cytotoxic activity indicating that it is not ideal as a candidate against Gram-negative bacteria. The acceptable toxicity profile and rapid antibacterial activity against MRSA highlight the potential of these molecules for further studies as anti-MRSA agents.

Design, synthesis and mechanistic anticancer activity of new acetylated 5-aminosalicylate-thiazolinone hybrid derivatives

The development of hybrid compounds has been widely considered as a promising strategy to circumvent the difficulties that emerge in cancer treatment. The well-established strategy of adding acetyl groups to certain drugs has been demonstrated to enhance their therapeutic efficacy. Based on our previous work, an approach of accommodating two chemical entities into a single structure was implemented to synthesize new acetylated hybrids (HH32 and HH33) from 5-aminosalicylic acid and 4-thiazolinone derivatives. These acetylated hybrids showed potential anticancer activities and distinct metabolomic profile with antiproliferative properties. The in-silico molecular docking predicts a strong binding of HH32 and HH33 to cell cycle regulators, and transcriptomic analysis revealed DNA repair and cell cycle as the main targets of HH33 compounds. These findings were validated using in vitro models. In conclusion, the pleiotropic biological effects of HH32 and HH33 compounds on cancer cells demonstrated a new avenue to develop more potent cancer therapies.

X-ray Diffraction of Water in Polyvinylpyrrolidone

PVP is a hydrophilic polymer commonly used as an excipient in pharmaceutical formulations. Here we have performed time-resolved high-energy X-ray scattering experiments on pellets of PVP at different humidity conditions for 1-2 days. A two-phase exponential decay in water sorption is found with a peak in the differential pair distribution function at 2.85 Å, which is attributed to the average (hydrogen bonded) carbonyl oxygen-water oxygen distance. Additional scattering measurements on powders with fixed compositions ranging from 2 to 12.3 wt % H₂O were modeled with Empirical Potential Structure Refinement (EPSR). The models reveal approximately linear relations between the carbonyl oxygen-water oxygen coordination number (n_OC-OW) and the water oxygen-water oxygen coordination number (n_OW-OW) versus water content in PVP. A stronger preference for water-water hydrogen bonding over carbonyl-water bonding is found. At all the concentrations studied the majority of water molecules were found to be randomly isolated, but a wide distribution of coordination environments of water molecules is found within the PVP polymer strands at the highest concentrations. Overall, the EPSR models indicate a continuous evolution in structure versus water content with n_OW-OW=1 occurring at ∼12 wt % H₂O, i.e., the composition where, on average, each water molecule is surrounded by one other water molecule.

RNA- and ATAC-sequencing Reveals a Unique CD83+ Microglial Population Focally Depleted in Parkinson's Disease

All brain areas affected in Parkinson's disease (PD) show an abundance of microglia with an activated morphology together with increased expression of pro-inflammatory cytokines, suggesting that neuroinflammation may contribute to the neurodegenerative process in this common and incurable disorder. We applied a single nucleus RNA- and ATAC-sequencing approach using the 10x Genomics Chromium platform to postmortem PD samples to investigate microglial heterogeneity in PD. We created a multiomic dataset using substantia nigra (SN) tissues from 19 PD donors and 14 non-PD controls (NPCs), as well as three other brain regions from the PD donors which are differentially affected in this disease: the ventral tegmental area (VTA), substantia inominata (SI), and hypothalamus (HypoTs). We identified thirteen microglial subpopulations within these tissues as well as a perivascular macrophage and a monocyte population, of which we characterized the transcriptional and chromatin repertoires. Using this data, we investigated whether these microglial subpopulations have any association with PD and whether they have regional specificity. We uncovered several changes in microglial subpopulations in PD, which appear to parallel the magnitude of neurodegeneration across these four selected brain regions. Specifically, we identified that inflammatory microglia in PD are more prevalent in the SN and differentially express PD-associated markers. Our analysis revealed the depletion of a CD83 and HIF1A- expressing microglial subpopulation, specifically in the SN in PD, that has a unique chromatin signature compared to other microglial subpopulations. Interestingly, this microglial subpopulation has regional specificity to the brainstem in non-disease tissues. Furthermore, it is highly enriched for transcripts of proteins involved in antigen presentation and heat-shock proteins, and its depletion in the PD SN may have implications for neuronal vulnerability in disease.

Design and synthesis of new adamantyl derivatives as promising antiproliferative agents

A series of adamantyl carboxamide derivatives containing sulfonate or sulfonamide moiety were designed as multitargeted inhibitors of ectonucleotide pyrophosphatases/phosphodiesterases (NPPs) and carbonic anhydrases (CAs). The target compounds were investigated for their antiproliferative activity against NCI-60 cancer cell lines panel. Three main series composed of 3- and 4-aminophenol, 4-aminoaniline, and 5-hydroxyindole scaffolds were designed based on a lead compound (A). Compounds 1e (benzenesulfonyl) and 1i (4-fluorobenzenesulfonyl) of 4-aminophenol backbone exhibited the most promising antiproliferative activity. Both compounds exhibited a broad-spectrum and potent inhibition against all the nine tested cancer subtypes. Both compounds showed nanomolar IC50 values over several cancer cell lines that belong to leukemia and colon cancer such as K-562, RPMI-8226, SR, COLO 205, HCT-116, HCT-15, HT29, KM12, and SW-620 cell lines. Compounds 1e and 1i induced apoptosis in K-562 leukemia cells in a dose-dependent manner. Compound 1i showed the highest cytotoxic activity with IC50 value of 200 nM against HT29 cell line. In addition, compounds 1e and 1i were tested against normal breast cells (HME1) and normal skin fibroblast cells (F180) and the results revealed that the compounds are safe toward normal cells compared to cancers cells. Enzymatic assays against NPP1-3 and carbonic anhydrases II, IX, and XII were performed to investigate the possible molecular target(s) of compounds 1e and 1i. Furthermore, a molecular docking study was performed to predict the binding modes of compounds 1e and 1i in the active site of the most sensitive enzymes subtypes.

Efficient selective targeting of Candida CYP51 by oxadiazole derivatives designed from plant cuminaldehyde

Candida infection represents a global threat with associated high resistance and mortality rate. Azoles such as the triazole drug fluconazole are the frontline therapy against invasive fungal infections; however, the emerging multidrug-resistant strains limit their use. Therefore, a series of novel azole UOSO1-15 derivatives were developed based on a modified natural scaffold to combat the evolved resistance mechanism and to provide improved safety and target selectivity. The antifungal screening against C. albicans and C. auris showed that UOSO10 and 12-14 compounds were the most potent derivatives. Among them, UOSO13 exhibited superior potent activity with MIC50 values of 0.5 and 0.8 μg mL-1 against C. albicans and C. auris compared to 25 and 600 μg mL-1 for fluconazole, respectively. UOSO13 displayed significant CaCYP51 enzyme inhibition activity in a concentration-dependent manner with an IC50 10-fold that of fluconazole, while exhibiting no activity against human CYP50 enzyme or toxicity to human cells. Furthermore, UOSO13 caused a significant reduction of Candida ergosterol content by 70.3% compared to a 35.6% reduction by fluconazole. Homology modeling, molecular docking, and molecular dynamics simulations of C. auris CYP51 enzyme indicated the stability and superiority of UOSO13. ADME prediction indicated that UOSO13 fulfils the drug-likeness criteria with good physicochemical properties.

Mass spectroscopy-based proteomics and metabolomics analysis of triple-positive breast cancer cells treated with tamoxifen and/or trastuzumab

PURPOSE

HER2-enriched breast cancer with high levels of hormone receptor expression, known as "triple positive" breast cancer, may represent a new entity with a relatively favourable prognosis against which the combination of chemotherapy, HER-2 inhibition, and endocrine treatment may be considered overtreatment. We explored the effect of the anticancer drugs tamoxifen and trastuzumab, both separately and in combination, on the integrated proteomic and metabolic profile of "triple positive" breast cancer cells (BT-474).

METHOD

We employed ultra-high-performance liquid chromatography-quadrupole time of flight mass spectrometry using a Bruker timsTOF to investigate changes in BT-474 cell line treated with either tamoxifen, trastuzumab or a combination. Differentially abundant metabolites were identified using the Bruker Human Metabolome Database metabolite library and proteins using the Uniprot proteome for Homo sapiens using MetaboScape and MaxQuant, respectively, for identification and quantitation.

RESULTS

A total of 77 proteins and 85 metabolites were found to significantly differ in abundance in BT-474 treated cells with tamoxifen 5 μM/and or trastuzumab 2.5 μM. Findings suggest that by targeting important cellular signalling pathways which regulate cell growth, apoptosis, proliferation, and chemoresistance, these medicines have a considerable anti-growth effect in BT-474 cells. Pathways enriched for dysregulation include RNA splicing, neutrophil degranulation and activation, cellular redox homeostasis, mitochondrial transmembrane transport, ferroptosis and necroptosis, ABC transporters and central carbon metabolism.

CONCLUSION

Our findings in protein and metabolite level research revealed that anti-cancer drug therapy had a significant impact on the key signalling pathways and molecular processes in triple positive BT-474 cell lines.

Effect of safranal on the response of cancer cells to topoisomerase I inhibitors: Does sequence matter?

Lung and colorectal cancers are among the leading causes of death from cancer worldwide. Although topotecan (TPT), a topoisomerase1 inhibitor, is a first- and second-line drug for lung and colon cancers, the development of drug resistance and toxicity still remain as a major obstacle to chemotherapeutic success. Accumulating evidence indicates increased efficacy and reduced toxicity of chemotherapeutic agents upon combining them with natural products. We aimed to investigate the possible interaction of safranal (SAF), a natural compound obtained from Crocus sativus stigma, with TPT when used in different sequences in colon and lung cancer cell lines. The growth inhibitory effect of the proposed combination given in different sequences was assessed using the colony formation assay. The comet assay, cell cycle distribution, Annexin-V staining, and expression of proteins involved in DNA damage/repair were utilized to understand the mechanism underlying the effect of the combination. SAF enhanced the growth inhibitory effects of TPT particularly when it was added to the cells prior to TPT. This combination increased the double-strand break induction and dysregulated the DNA repair machinery, particularly the tyrosyl-DNA phosphodiesterase 1 enzyme. In addition, the SAF + TPT combination increased the fraction of cells arrested at the G2/M checkpoint as well as enhanced the induction of apoptosis. The current study highlights the status of SAF as a natural product sensitizing the lung and colon cancer cells to the cytotoxic effects of the anticancer drug TPT. In addition, it emphasizes the importance of sequence-dependent interaction which can affect the overall outcome.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

871 The Efficacy and Safety of Bariatric Surgery in Patients with End-Stage Renal Disease Awaiting Listing for Kidney Transplantation: A Systematic Review and Meta-Analysis

Aim

Obesity is associated with adverse outcomes in end-stage renal disease (ESRD) and hinders changes for waiting list allocation of kidney transplantation (KT). Bariatric surgery (BS) is an effective solution to obesity. The authors aim to summarise the evidence for the efficacy and safety of BS in ESRD awaiting KT.

Method

We performed a systematic review and meta-analysis to determine the efficacy and safety of BS in patients with ESRD awaiting KT. A literature search of MEDLINE, EMBASE and Web of Science was conducted from inception to April 2021. The methodological quality of selected studies was assessed using the Newcastle-Ottowa tool. Our primary outcome was change in BMI, with secondary outcomes including adverse events, graft outcomes and KT listing rate.

Results

Nine observational studies met the inclusion criteria with a total of 1903 patients (43.9% male). Mean change in BMI following BS was -11.3 (-15.3 to -7.3, p &lt;0.001) within a median follow up time of 27.6 months (IQR 12 to 36.6 months). Sleeve gastrectomy (44.6%, n=849) and gastric bypass (43.6%, n=829) were the most common procedures. Mean age at BS was 47.3 years with a mean rate to KT listing of 59.9% (SD = 1.13).

Conclusion

This review highlights that BS is both safe and efficacious on patients with ESRD and can aid with optimisation for waiting list allocation.

870 The Efficacy and Safety of Bariatric Surgery in Kidney Transplantation Candidates: A Systematic Review and Meta-Analysis

Introduction

Kidney transplantation (KT) remains a high-risk procedure which requires extensive pre-operative assessment and optimisation. Obesity is known to increase the risk of adverse post-operative consequences. Bariatric surgery (BS) is an effective solution to obesity. The authors aim to summarise the evidence for the efficacy and safety of BS in KT candidates.

Method

We performed a systematic review and meta-analysis to determine the efficacy and safety of BS in patients KT candidates. A literature search of MEDLINE, EMBASE and Web of Science was conducted from inception to April 2021. The methodological quality of selected studies was assessed using the Newcastle-Ottowa tool. Our primary outcome was change in BMI, with secondary outcomes including adverse events, graft outcomes and KT rate.

Results

Nine observational studies met the inclusion criteria with a total of 179 patients (48% male). Mean change in BMI following BS was -11.2 (-12.9 to -9.5, p &lt; 0.001) within a median follow up time of 43 months (IQR 36 to 47 months). Sleeve gastrectomy (44.7%, n=80) and gastric bypass (46.9%, n=84) were the most common procedures. Median time from BS to KT was 17 months (IQR 6 to 18 months) with a mean KT rate of 80.1% (SD = 14.9).

Conclusion

This review highlights that BS is both safe and efficacious for KT candidates and can be an effective means of optimising BMI prior to transplantation.

268 The Efficacy and Safety of Bariatric Surgery in Patients with End-Stage Renal Disease and Kidney Transplantation: A Systematic Review and Meta-Analysis

Aim

Obesity is associated with adverse outcomes in end-stage renal disease (ESRD) and kidney transplant (KT) recipients. Bariatric surgery (BS) is an effective solution to obesity. The authors aim to summarise the evidence for the efficacy and safety of BS in ESRD or KT.

Method

A literature search was conducted using MEDLINE, EMBASE and Web of Science from inception to date (April 2021). Articles were categorised into patients awaiting waiting list acceptance, awaiting transplantation, undergoing simultaneous BS and kidney transplantation, and undergoing BS following transplantation in the past. Primary outcome was change in BMI with secondary outcomes as adverse events, graft outcomes and KT.

Results

Twenty-eight articles were selected: fourteen on patients awaiting listing (n = 1984), nine on patients listed for KT (n = 196), one on simultaneous BS and KT and ten on patients undergoing BS following KT (n = 198). Mean change in BMI for patients awaiting listing was -10.5 (-4.1 to -17.0, p = 0.001), change in BMI for patients listed for KT was -11.2 (-9.5 to -12.9, p&lt;0.001) and change for patients with prior KT was -11.0 (-7.09 to -14.9, p&lt;0.001). 60.4% of patients undergoing BS were successfully listed for KT. 74.1% of patients listed for KT undergoing BS underwent KT within 17 months (SD = 78.5). Time from KT to BS was 59.2 months (SD = 43.0).

Conclusion

BS is both safe and efficacious on patients with ESRD, those awaiting KT, and those with prior KT and should be considered when obesity is a hurdle to favourable outcomes.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

796 THE IMPORTANCE OF CHEST X RAYS AS AN INITIAL INVESTIGATION IN ROUTINE ACUTE ELDERLY CARE ADMISSIONS

Introduction

The Chest X-Ray (CXR) is a common and central initial investigation for any patient that has been admitted via Accident and Emergency (A&E). In the context of elderly care, it is a useful measure of a patient’s baseline functional status as well as a tool for cancer surveillance and other aspects of clinical care. Accurate documentation of CXR review is also imperative for closed loop communication of clinical information amongst a multi-disciplinary team.

Methods

Twenty-eight random inpatients in a local NHS Trust Healthcare of Older People (HCOP) department were selected to be part of this two-cycle study. Using hospital database records, the CARESTREAM imaging system and patient clinical documentation, data including the following was collected: whether a CXR was completed, was CXR review documented in patient notes and initial reason for admission. As per local practice, all acute HCOP admissions should undergo a CXR and have an image review clearly documented in patients’ clinical noting. The established target was 95% compliance for both. Following intervention by way of ward poaters and presentation at a local quality improvement meeting the cycle was repeated to ascertain improvement in compliance.

Results

22 (79%) HCOP patients had a CXR on admission. Of those completed CXRs, only 6 (27%) of these showed evidence of review (documentation in clinical noting). Following the above mentioned interventions, 25 (89%) of HCOP patients had a CXR on admission, showing an improvement. Of those completed CXRs, 20 (80%) showed evidence of documented clinical review– once again showing improvement.

Conclusions

CXRs and their accurate documentation is an important aspect of the holistic care of the HCOP patient. Ensuring that compliance for completing the scan and documenting results should be a priority in clinical quality and safety. Our interventions have shown an improvement in compliance and resulted in sustainable change.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

Discovery of novel class of histone deacetylase inhibitors as potential anticancer agents

Selective inhibition of histone deacetylases (HDACs) is an important strategy in the field of anticancer drug discovery. However, lack of inhibitors that possess high selectivity toward certain HDACs isozymes is associated with adverse side effects that limits their clinical applications. We have initiated a collaborative initiatives between multi-institutions aimed at the discovery of novel and selective HDACs inhibitors. To this end, a phenotypic screening of an in-house pilot library of about 70 small molecules against various HDAC isozymes led to the discovery of five compounds that displayed varying degrees of HDAC isozyme selectivity. The anticancer activities of these molecules were validated using various biological assays including transcriptomic studies. Compounds 15, 14, and 19 possessed selective inhibitory activity against HDAC5, while 28 displayed selective inhibition of HDAC1 and HDAC2. Compound 22 was found to be a selective inhibitor for HDAC3 and HDAC9. Importantly, we discovered a none-hydroxamate based HDAC inhibitor, compound 28, representing a distinct chemical probe of HDAC inhibitors. It contains a trifluoromethyloxadiazolyl moiety (TFMO) as a non-chelating metal-binding group. The new compounds showed potent anti-proliferative activity when tested against MCF7 breast cancer cell line, as well as increased acetylation of histones and induce cells apoptosis. The new compounds apoptotic effects were validated through the upregulation of proapoptotic proteins caspases3 and 7 and downregulation of the antiapoptotic biomarkers C-MYC, BCL2, BCL3 and NFĸB genes. Furthermore, the new compounds arrested cell cycle at different phases, which was confirmed through downregulation of the CDK1, 2, 4, 6, E2F1 and RB1 proteins. Taken together, our findings provide the foundation for the development of new chemical probes as potential lead drug candidates for the treatment of cancer.

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Identification of robust and interpretable brain signatures of autism and clinical symptom severity using a dynamic time-series deep neural network

Introduction

Autism spectrum disorder (ASD) is among the most common and pervasive neurodevelopmental disorders. Yet, despite decades of research, the neurobiology of ASD is still poorly understood, as inconsistent findings preclude the identification of robust and interpretable neurobiological markers and predictors of clinical symptoms.

Objectives

Identify robust and interpretable dynamic brain markers that distinguish children with ASD from typically-developing (TD) children and predict clinical symptom severity.

Methods

We leverage multiple functional brain imaging cohorts (ABIDE, Stanford; N = 1004) and exciting recent advances in explainable artificial intelligence (xAI), to develop a novel multivariate time series deep neural network model that extracts informative brain dynamics features that accurately distinguish between ASD and TD children, and predict clinical symptom severity.

Results

Our model achieved consistently high classification accuracies in cross-validation analysis of data from the ABIDE cohort. Crucially, despite the differences in symptom profiles, age, and data acquisition protocols, our model also accurately classified data from an independent Stanford cohort without additional training. xAI analyses revealed that brain features associated with the default mode network, and the human voice/face processing and communication systems, most clearly distinguished ASD from TD children in both cohorts. Furthermore, the posterior cingulate cortex emerged as robust predictor of the severity of social and communication deficits in ASD in both cohorts.

Conclusions

Our findings, replicated across two independent cohorts, reveal robust and neurobiologically interpretable brain features that detect ASD and predict core phenotypic features of ASD, and have the potential to transform our understanding of the etiology and treatment of the disorder.

Disclosure

No significant relationships.

Natural compound catechol induces DNA damage, apoptosis, and G1 cell cycle arrest in breast cancer cells

Targeting cell cycle and inducing DNA damage by activating cell death pathways are considered as effective therapeutic strategy for combating breast cancer progression. Many of the naturally known small molecules target these signaling pathways and are effective against resistant and/or aggressive types of breast cancers. Here, we investigated the effect of catechol, a naturally occurring plant compound, for its specificity and chemotherapeutic efficacies in breast cancer (MCF-7 and MDA-MB-231) cells. Catechol treatment showed concentration-dependent cytotoxicity and antiproliferative growth in both MCF-7 and MDA-MB-231 cells while sparing minimal effects on noncancerous (F-180 and HK2) cells. Catechol modulated differential DNA damage effects by activating ATM/ATR pathways and showed enhanced γ-H2AX expression, as an indicator for DNA double-stranded breaks. MCF-7 cells showed G1 cell cycle arrest by regulating p21-mediated cyclin E/Cdk2 inhibition. Furthermore, activation of p53 triggered a caspase-mediated cell death mechanism by inhibiting regulatory proteins such as DNMT1, p-BRCA1, MCL-1, and PDCD6 with an increased Bax/Bcl-2 ratio. Overall, our results showed that catechol possesses favorable safety profile for noncancerous cells while specifically targeting multiple signaling cascades to inhibit proliferation in breast cancer cells.

Design, synthesis, and computational validation of novel compounds selectively targeting HER2-expressing breast cancer

Human epidermal growth factor receptor (HER) is a family of multidomain proteins that plays important role in the regulation of several biological functions. HER2 is a member of HER that is highly presented in breast cancer cells. Here, we designed and synthesized a series of diaryl urea/thiourea compounds. The compounds were tested on HER2⁺ breast cancer cells including MCF-7 and SkBr3, compared to HER2^- breast cancer cells including MDA-MB-231 and BT-549. Only compounds 12-14 at 10 µM showed selective anti-proliferative activity against MCF-7 and SkBr3 by 65-79%. Compounds 12-14 showed >80% inhibition of the intracellular kinase domain of HER2. The results obtained indicated that compounds 12-14 are selectively targeting HER2⁺ cells. The IC₅₀ of compound 13 against MCF-7 and SkBR3 were 1.3 ± 0.009 and 0.73 ± 0.03 µM, respectively. Molecular docking and MD simulations (50 ns) were carried out, and their binding free energies were calculated. Compounds 12-14 formed strong hydrogen bond and pi-pi stacking interactions with the key residues Thr862 and Phe864. 3DQSAR model confirmed the role of 3-bromo substituent of pyridine ring and 4-chloro substituent of phenyl ring in the activity of the compounds. In conclusion, novel compounds, particularly 13 were developed selectively against HER2-expressing/overexpressing breast cancer cells including MCF7 and SkBr3.

Efficacy of vitamin D supplementation in major depression: A meta-analysis of randomized controlled trials

Background:

There is a need to develop and periodically evaluate new treatment strategies in major depression due to the high burden of nonresponse and inadequate response to antidepressants.

Aim:

We aimed to assess the effect of vitamin D supplementation on depression symptom scores among individuals with clinically diagnosed major depression.

Materials and Methods:

Electronic search of databases was carried out for published randomized controlled trials in English language, peer-reviewed journals from inception till August 2017. Outcome measure used for effect size calculation was depression symptom scores. Effect sizes for the trials were computed using standardized mean difference (Cohen's d), and I² test was used to assess sample heterogeneity. Pooled mean effect sizes were derived using both fixed and random-effects model. Critical appraisal of studies was done using the Cochrane risk of bias assessment tool.

Results:

A total of four trials involving 948 participants were included in the study. In three trials, the intervention group received oral vitamin D supplementation whereas in one parenteral vitamin D was given. Pooled mean effect size for vitamin D supplementation on depressive symptom ratings in major depression was 0.58 (95% confidence interval, 0.45–0.72). The I² value for heterogeneity was 0 suggesting low heterogeneity among studies. Egger plot intercept indicated minimal publication bias.

Conclusion:

Vitamin D supplementation favorably impacted depression ratings in major depression with a moderate effect size. These findings must be considered tentative owing to the limited number of trials available and inherent methodological bias noted in few of them.

Neural correlates of cognitive variability in childhood autism and relation to heterogeneity in decision-making dynamics

Heterogeneity in cognitive and academic abilities is a prominent feature of autism spectrum disorder (ASD), yet little is known about its underlying causes. Here we combine functional brain imaging during numerical problem-solving with hierarchical drift-diffusion models of behavior and standardized measures of numerical abilities to investigate neural mechanisms underlying cognitive variability in children with ASD, and their IQ-matched Typically Developing (TD) peers. Although the two groups showed similar levels of brain activation, the relation to individual abilities differed markedly in ventral temporal-occipital, parietal and prefrontal regions important for numerical cognition: children with ASD showed a positive correlation between functional brain activation and numerical abilities, whereas TD children showed the opposite pattern. Despite similar accuracy and response times, decision thresholds were significantly higher in the ASD group, suggesting greater evidence required for problem-solving. Critically, the relationship between individual abilities and engagement of prefrontal control systems anchored in the anterior insula was differentially moderated by decision threshold in subgroups of children with ASD. Our findings uncover novel cognitive and neural sources of variability in academically-relevant cognitive skills in ASD and suggest that multilevel measures and latent decision-making dynamics can aid in characterization of cognitive variability and heterogeneity in neurodevelopmental disorders.

Infectious diseases and antimicrobial prescribing: Online spaced education for junior doctors

BACKGROUND

Inappropriate antimicrobial prescribing may harm patients and drive antimicrobial resistance. Junior doctors' knowledge of infectious diseases and antimicrobial prescribing is inadequate. Online spaced case-based learning can improve knowledge.

OBJECTIVE

To develop infectious diseases and antimicrobial prescribing course content for online spaced education and assess its effectiveness and feasibility for junior doctors.

METHODS

Infectious diseases and antimicrobial course content was developed for an online spaced education platform (Qstream Inc., Burlington, MA). Junior doctors (postgraduate years 1-3) at two tertiary teaching hospitals in Sydney participated in the study. Course content was provided with Qstream at one hospital and at the other hospital via two face-to-face (FTF) tutorials from August to October 2017. Knowledge and self-confidence were compared before and after training within and between both cohorts.

RESULTS

Participation in the course was higher in the Qstream cohort with 48/127 (37.8%) completing the course compared with 44/110 (40%) attending one or both FTF sessions, of whom 22/110 (20%) attended both. Improvement in mean knowledge score from 69.7% to 81.5% in the Qstream cohort was significantly greater than the FTF cohort's minimal improvement from 67.6% to 67.9% (95% CI 2.79-20.33; P=0.01). In the Qstream cohort mean confidence rating (0-10) improvement from 5.14 to 6.55 was greater than the FTF group improvement from 5.37 to 5.85 (95% CI 0.132-1.171; P=0.02). Qstream feedback was very positive.

CONCLUSIONS

Online spaced education in infectious diseases and antimicrobial prescribing was feasible, acceptable and effective for junior doctors. It has potential to reduce inappropriate antimicrobial prescribing and warrants further investigation.

P1951Serial left ventricular global longitudinal strain and mortality in patients with Takotsubo cardiomyopathy

Background

Recent studies on Takotsubo cardiomyopathy (TC) have challenged the common conception that it is a relatively benign condition with functional recovery observed in the majority of cases. However, it is important to recognize that overt functional recovery might not reflect the true regional recovery, which might have an adverse impact on survival.

Objective

We sought to assess baseline and follow-up left ventricular function characteristics and their impact on longer-term mortality in patients presenting with documented Takotsubo cardiomyopathy (TC) at a tertiary centre.

Methods

339 patients (66±14 years, 88% women) presented to our centre between 2006 and 2018 with acute anginal symptoms and were subsequently diagnosed with TC following clinical and angiographic evaluation. All patients returned for a follow-up evaluation including transthoracic echocardiography (TTE). Baseline and follow-up (3–6 months after TC diagnosis) LV ejection fraction (LVEF) and LV global longitudinal strain (LV-GLS using velocity vector imaging) were recorded on TTE. The primary endpoint was longer-term mortality.

Results

Hypertension, dyslipidaemia, and diabetes were present in 71%, 56%, and 26% of patients. Baseline mean troponin I peak, LVEF and LV-GLS were 0.9±7 ng/ml, 36±9%, and 11±3%; respectively. 94% had baseline LVEF<50%, 272 (80%) had apical ballooning, and 94% had LV-GLS worse than −18%. No patient had angiographically obstructive coronary artery disease. At 3–6 months follow-up, mean LVEF, and LV-GLS improved to 57±9% and 16±3%, respectively. 87% of patients had LVEF >50%, but in 70% LV-GLS remained worse than −18%. After 3.3±3 years, 72 patients (21%) died. On multivariable Cox survival analysis (adjusted for age, gender, baseline troponin peak and follow up LVEF), follow up LV-GLS was independently associated with longer-term mortality (hazard ratio 1.12 [95% confidence interval 1.05, 1.20], p<0.001). Significantly more patients with follow up LV-GLS worse than −18% died vs. those with LV-GLS better than −18% (57/237 [24%] vs. 15/102 [15%], log-rank statistic p-value 0.01, Kaplan-Meier figure 1).

Kaplan-Meier curve of freedom from death

Conclusions

In this large single-centre study of patients with documented TC (majority women), 87% recovered LVEF at 3–6 months, but in 70% LV-GLS remained worse than −18%, which was independently associated with higher longer-term mortality.

Psychiatric disorders and obesity: A review of association studies

Background:

Inconsistent evidence exists regarding the strength, direction, and moderators in the relationship between obesity and psychiatric disorders.

Aim:

This study aims to summarize the evidence on the association between psychiatric illness and obesity with particular attention to the strength and direction of association and also the possible moderators in each postulated link.

Materials and Methods:

Systematic electronic searches of MEDLINE through PubMed, ScienceDirect, PsycINFO, and Google Scholar were carried out from inception till October 2016. Generated abstracts were screened for eligibility to be included in the review. Study designs that evaluated the strength of relationship between obesity and psychiatric disorders were included in the study. Quality assessment of included studies was done using the Newcastle–Ottawa checklist tool.

Results:

From a total of 2424 search results, 21 eligible articles were identified and reviewed. These included studies on obesity and depression (n = 15), obesity and anxiety (four) and one each on obesity and personality disorders, eating disorder (ED), attention deficit hyperactivity disorder, and alcohol use. Maximal evidence existed for the association between depression and obesity with longitudinal studies demonstrating a bidirectional link between the two conditions. The odds ratios (ORs) were similar for developing depression in obesity (OR: 1.21–5.8) and vice versa (OR: 1.18–3.76) with a stronger association observed in women. For anxiety disorders, evidence was mostly cross-sectional, and associations were of modest magnitude (OR: 1.27–1.40). Among other disorders, obesity, and EDs appear to have a close link (OR: 4.5). Alcohol use appears to be a risk factor for obesity and not vice versa but only among women (OR: 3.84).

Conclusion:

Obesity and depression have a significant and bidirectional association. Evidence is modest for anxiety disorders and inadequate for other psychiatric conditions. Gender appears to be an important mediator in these relationships.

Inhibition of SHP2 by new compounds induces differential effects on RAS/RAF/ERK and PI3K/AKT pathways in different cancer cell types

Kinases and phosphatases are important players in growth signaling and are involved in cancer development. For development of targeted cancer therapy, attention is given to kinases rather than phosphatases inhibitors. Src homology region 2 domain-containing protein tyrosine phosphatase2 (SHP2) is overexpressed in different types of cancers. We investigated the SHP2-inhibitory effects of two new 5-aminosalicylate-4-thiazolinones in human cervical (HeLa) and breast (MCF-7 & MDA-MB-231) cancer cells. In-silico molecular docking showed preferential affinity of the two compounds towards the catalytic over the allosteric site of SHP2. An enzymatic assay confirmed the docking results whereby 0.01 μM of both compounds reduced SHP2 activity to 50%. On cellular level, the two compounds significantly reduced the expression of SHP2, KRAS, p-ERK and p-STAT3 in HeLa but not in the other two cell lines. Phosphorylation of AKT and JNK was enhanced in HeLa and MCF7. Both compounds exhibited anti-proliferative/anti-migratory effects on HeLa and MCF7 but not in MDA-MB-231 cells. These results indicate that inhibition of SHP2 and its downstream pathways by the two compounds might be a promising strategy for cancer therapy in some but not all cancer types.

DNA-dependent protein kinase: Epigenetic alterations and the role in genomic stability of cancer

DNA-dependent protein kinase (DNA-PK), a member of phosphatidylinositol-kinase family, is a key protein in mammalian DNA double-strand break (DSB) repair that helps to maintain genomic integrity. DNA-PK also plays a central role in immune cell development and protects telomerase during cellular aging. Epigenetic deregulation due to endogenous and exogenous factors may affect the normal function of DNA-PK, which in turn could impair DNA repair and contribute to genomic instability. Recent studies implicate a role for epigenetics in the regulation of DNA-PK expression in normal and cancer cells, which may impact cancer progression and metastasis as well as provide opportunities for treatment and use of DNA-PK as a novel cancer biomarker. In addition, several small molecules and biological agents have been recently identified that can inhibit DNA-PK function or expression, and thus hold promise for cancer treatments. This review discusses the impact of epigenetic alterations and the expression of DNA-PK in relation to the DNA repair mechanisms with a focus on its differential levels in normal and cancer cells.

Directional emission of rhodamine 6G on top of a silver grating

We have observed directional spontaneous emission of rhodamine 6G dye deposited on top of a silver grating and found that its angular distribution patterns were very different in TE and TM polarizations. The latter was related to the dispersion curves determined based on the polarized reflection spectra measured at multiple incidence angles. The most intriguing finding of this Letter was a resonance, which was coupled with TE-polarized light and determined the characteristic double-crescent patterns in the TE-polarized spontaneous emission. This observation, as well as nearly similar resonance observed in TM polarization, was tentatively explained in terms of leaky waveguide modes supported by a film of dye-doped polymer.

A report on an acute, in-hours, outpatient review clinic with ultrasonography facilities for the early evaluation of general surgical patients

Introduction In 2013 our hospital introduced an in-hours, consultant-led, outpatient acute surgical clinic (ASC) for emergency general surgical patients. In 2014 this clinic was equipped with a dedicated ultrasonography service. This prospective cohort study evaluated this service before and after the introduction of ultrasonography facilities. Methods Data were recorded prospectively for all patients attending the clinic during 2013 and 2014. The primary outcome was patient destination (whether there was follow-up/admission) after clinic attendance. Results The ASC reviewed patients with a wide age range and array of general surgical complaints. In 2013, 186 patients attended the ASC. After the introduction of the ultrasonography service in 2014, 304 patients attended. In 2014, there was a reduction in the proportion of patients admitted to hospital from the clinic (18.3% vs 8.9%, p=0.002). However, the proportion of patients discharged after ASC review remained comparable with 2013 (30.1% in 2013 vs 38.8% in 2014, p=0.051). The proportion of patients undergoing computed tomography (CT) scans also fell (14.0% vs 4.9%, p<0.001). Conclusions The ASC assessed a wide array of general surgical complaints. Only a small proportion required hospital admission. The introduction of an ultrasonography service was associated with a further reduction in admission rates and computed tomography.

Memory and cognitive control circuits in mathematical cognition and learning

Numerical cognition relies on interactions within and between multiple functional brain systems, including those subserving quantity processing, working memory, declarative memory, and cognitive control. This chapter describes recent advances in our understanding of memory and control circuits in mathematical cognition and learning. The working memory system involves multiple parietal-frontal circuits which create short-term representations that allow manipulation of discrete quantities over several seconds. In contrast, hippocampal-frontal circuits underlying the declarative memory system play an important role in formation of associative memories and binding of new and old information, leading to the formation of long-term memories that allow generalization beyond individual problem attributes. The flow of information across these systems is regulated by flexible cognitive control systems which facilitate the integration and manipulation of quantity and mnemonic information. The implications of recent research for formulating a more comprehensive systems neuroscience view of the neural basis of mathematical learning and knowledge acquisition in both children and adults are discussed.

Anhedonia and general distress show dissociable ventromedial prefrontal cortex connectivity in major depressive disorder

Anhedonia, the reduced ability to experience pleasure in response to otherwise rewarding stimuli, is a core symptom of major depressive disorder (MDD). Although the posterior ventromedial prefrontal cortex (pVMPFC) and its functional connections have been consistently implicated in MDD, their roles in anhedonia remain poorly understood. Furthermore, it is unknown whether anhedonia is primarily associated with intrinsic 'resting-state' pVMPFC functional connectivity or an inability to modulate connectivity in a context-specific manner. To address these gaps, a pVMPFC region of interest was first identified using activation likelihood estimation meta-analysis. pVMPFC connectivity was then examined in relation to anhedonia and general distress symptoms of depression, using both resting-state and task-based functional magnetic resonance imaging involving pleasant music, in current MDD and healthy control groups. In MDD, pVMPFC connectivity was negatively correlated with anhedonia but not general distress during music listening in key reward- and emotion-processing regions, including nucleus accumbens, ventral tegmental area/substantia nigra, orbitofrontal cortex and insula, as well as fronto-temporal regions involved in tracking complex sound sequences, including middle temporal gyrus and inferior frontal gyrus. No such dissociations were observed in the healthy controls, and resting-state pVMPFC connectivity did not dissociate anhedonia from general distress in either group. Our findings demonstrate that anhedonia in MDD is associated with context-specific deficits in pVMPFC connectivity with the mesolimbic reward system when encountering pleasurable stimuli, rather than a static deficit in intrinsic resting-state connectivity. Critically, identification of functional circuits associated with anhedonia better characterizes MDD heterogeneity and may help track of one of its core symptoms.

A prospective evaluation of retroequatorial recession of horizontal rectus muscles and Hertle-Dell'Osso tenotomy procedure in patients with infantile nystagmus with no definite null position

PURPOSE

To compare results of retroequatorial recession of horizontal rectus muscles and Hertle-Dell'Osso tenotomy procedure in patients with infantile nystagmus with null in primary position.

METHODS

In this prospective study, 10 subjects ≥5 years of age with infantile nystagmus with null in primary position were randomly assigned to two groups: group 1 underwent a large retroequatorial recession of the four horizontal rectus muscles; group 2, simple tenotomy and resuturing (Hertle-Dell'Osso procedure) of the four muscles. Patients were evaluated using Snellen and logMAR visual acuity charts, contrast sensitivity testing, color vision testing, stereopsis testing (TNO), and electronystagmography (ENG) for nystagmus waveforms, frequency, amplitude, and intensity.

RESULTS

Group 1 patients showed a trend toward 1-line improvement in their visual acuity for distance on the logMAR and ETDRS charts (P = 0.32); there was no improvement in group 2 patients. Contrast sensitivity improved significantly in both groups (P = 0.03), as did stereopsis (P = 0.02 [group 1], P = 0.04 [group 2]). The amplitude and intensity of nystagmus showed a tendancy to decrease in both the groups in all gazes, although the frequency showed no change in either group. Intergroup variability on all the parameters was not statistically significant.

CONCLUSIONS

Both retroequatorial recession of horizontal recti and the Hertle-Dell'Osso procedure showed a trend toward reducing ENG amplitude and improved contrast sensitivity and stereopsis in infantile nystagmus with null in primary position.

Predictors of weight loss at 1 year after laparoscopic adjustable gastric banding and the role of presurgical quality of life

BACKGROUND

There is uncertainty regarding preoperative predictors of a successful outcome for bariatric surgery (BarSurg), on which to determine appropriateness for such a procedure. Our aims were to identify preoperative clinical and psychosocial predictors of success following BarSurg and to explore the influence of body mass index (BMI) on these parameters.

METHODS

Preoperative data, including Impact of Weight on Quality of Life-Lite (IWQOL-Lite) scores transformed to Health-Related Quality of Life (HRQOL) scores, were accrued from 76 morbidly obese adults awaiting BarSurg. Pre- and postoperative data were also accrued for 26 patients who had completed 1-year follow-up post-bariatric surgery (laparoscopic adjustable gastric banding-LAGB). Statistical analysis was performed to assess the relationships between preoperative HRQOL scores, preoperative BMI and excess weight loss 1 year following BarSurg (EWL-1 year).

RESULTS

Preoperative BMI showed a significant independent, negative linear correlation with the public distress domain of preoperative quality of life (QOL) (r = -0.368, p = 0.001; β = -0.245, p = 0.009). Preoperative BMI had a significant, positive and independent association with EWL-1 year (r = 0.499, p = 0.009; β = 0.679, p = 0.015). Preoperative QOL scores had no association with EWL-1 year.

CONCLUSIONS

Preoperative BMI appears to predict EWL-1 year following restrictive bariatric surgery (LAGB). Preoperatively, patients with higher BMI appear to manifest greater public distress. Preoperative QOL scores, however, do not appear to have any predictive value for EWL-1 year post-LAGB. Preoperative BMI should therefore be employed as a predictor of EWL-1 year post-LAGB. Other measures of successful outcomes of bariatric surgeries (such as effects on QOL scores at 1 year) should be explored in future, larger and longer term studies.

Metal nanocluster light-emitting devices with suppressed parasitic emission and improved efficiency: exploring the impact of photophysical properties

Here we investigate the photophysical properties of Au(0)@Au(i)-thiolate nanoclusters by controlling the degree of aggregation, and measure electrochemical energy levels to design a metal nanocluster-based thin film LED (MNC-LED) structure. These efforts allow us to implement MNC-LEDs with luminance exceeding 40 cd m(-2) and external quantum efficiency exceeding 0.1% with clearly visible orange emission. It is also demonstrated that by varying the sizes of nanoclusters, the electroluminescence spectrum of the device can be tuned to the infrared emission, indicating the possibility of exploiting metal nanocluster emitters for use over a wide spectral range.