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In vitro inhibition of proliferation of SCLC cells by PEN-221 or DM1

Description of BT-984 synthesis and LC-MS/MS sample preparation

Immunohistochemical Analysis of SSTR2 Expression in 44 Small Cell Lung Cancer Patient Samples

Background Stress-induced hyperglycaemia at time of hospital admission has been linked to worse prognosis following acute myocardial infarction (AMI). In addition to glucose, other glucose-related indices, such as HbA1c, glucose-HbA1c ratio (GHR), and stress-hyperglycaemia ratio (SHR) are potential predictors of clinical outcomes following AMI. However, the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting adverse outcomes post-AMI are unknown. As such, we determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting 1-year all cause mortality in diabetic and non-diabetic ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) patients. Methods We undertook a national, registry-based study of patients with AMI from January 2008 to December 2015. We determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values using the Youden’s formula for 1-year all-cause mortality. We subsequently analyzed the sensitivity, specificity, positive and negative predictive values of the cut-off values in the diabetic and non-diabetic subgroups, stratified by the type of AMI. Results There were 5841 STEMI and 4105 NSTEMI in the study. In STEMI patients, glucose, GHR, and SHR were independent predictors of 1-year all-cause mortality [glucose: OR 2.19 (95% CI 1.74–2.76); GHR: OR 2.28 (95% CI 1.80–2.89); SHR: OR 2.20 (95% CI 1.73–2.79)]. However, in NSTEMI patients, glucose and HbA1c were independently associated with 1-year all-cause mortality [glucose: OR 1.38 (95% CI 1.01–1.90); HbA1c: OR 2.11 (95% CI 1.15–3.88)]. In diabetic STEMI patients, SHR performed the best in terms of area-under-the-curve (AUC) analysis (glucose: AUC 63.3%, 95% CI 59.5–67.2; GHR 68.8% 95% CI 64.8–72.8; SHR: AUC 69.3%, 95% CI 65.4–73.2). However, in non-diabetic STEMI patients, glucose, GHR, and SHR performed equally well (glucose: AUC 72.0%, 95% CI 67.7–76.3; GHR 71.9% 95% CI 67.7–76.2; SHR: AUC 71.7%, 95% CI 67.4–76.0). In NSTEMI patients, glucose performed better than HbA1c for both diabetic and non-diabetic patients in AUC analysis (For diabetic, glucose: AUC 52.8%, 95% CI 48.1–57.6; HbA1c: AUC 42.5%, 95% CI 37.6–47. For non-diabetic, glucose: AUC 62.0%, 95% CI 54.1–70.0; HbA1c: AUC 51.1%, 95% CI 43.3–58.9). The optimal cut-off values for glucose, GHR, and SHR in STEMI patients were 15.0 mmol/L, 2.11, and 1.68 for diabetic and 10.6 mmol/L, 1.72, and 1.51 for non-diabetic patients respectively. For NSTEMI patients, the optimal glucose values were 10.7 mmol/L for diabetic and 8.1 mmol/L for non-diabetic patients. Conclusions SHR was the most consistent independent predictor of 1-year all-cause mortality in both diabetic and non-diabetic STEMI, whereas glucose was the best predictor in NSTEMI patients.

Background Esophageal fistulae are rare, though serious, complications of anterior cervical surgery. Hardware-related issues are important etiologic factors. Patient-specific implants (PSIs) have increasingly been adapted to spinal surgery and offer a range of benefits. Zero-profile implants are a recent development primarily aimed at combating postoperative dysphagia. We report the first use of a 3-dimensional (3D)-printed zero-profile PSI in managing implant failure with migration and a secondary esophageal fistula. Methods A 68-year-old female had a prior C5-7 corpectomy with cage and plate fixation, as well as posterior C3-T1 lateral mass fixation, complicated by anterior plate displacement, resulting in pseudoarthrosis and an esophageal fistula. A 3D-printed zero-profile PSI was designed and implanted as part of a revision procedure to assist in recovery, prevent recurrence, and facilitate bony fusion. Results Optimal implant placement was achieved on the basis of preoperative virtual surgical planning. By 1 month postoperatively the patient had significantly improved, with evidence of esophageal fistula resolution and radiographic evidence of optimal implant placement. Conclusions Zero-profile 3D-printed PSIs may combat common and serious complications of anterior cervical surgery including postoperative dysphagia and esophageal fistulae. Further research is required to validate their widespread use for either cervical corpectomy or diskectomy and interbody fusion.

Background Stress-induced hyperglycaemia at time of hospital admission has been linked to worse prognosis following acute myocardial infarction (AMI). The stress-hyperglycaemia ratio (SHR) index normalises the acute increase in blood glucose values to background glycaemic status. However, the optimal cut-off blood glucose and SHR values for predicting adverse outcomes post-AMI are unknown. As such, we determined the optimal blood glucose and SHR cut-offs for predicting 1-year all cause mortality in diabetic and non-diabetic non-ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI) patients. Methods We undertook a national, registry-based study of patients with AMI from January 2008 to December 2015. We determined the optimal blood glucose and SHR cut-off values using the Youden’s formula for 1-year all-cause mortality. We subsequently analyzed the sensitivity, specificity, positive and negative predictive values of the cut-offs in the diabetic and non-diabetic subgroups, stratified by the type of AMI. Results There were 5,841 STEMI and 4,105 NSTEMI in the study. In STEMI patients, both glucose and SHR were independent predictors of 1-year all-cause mortality [Glucose: OR 2.19 (95% CI 1.74–2.75); SHR: 2.19 (95% CI 1.73–2.78)]. However, in NSTEMI patients, glucose and SHR were not independently associated with 1-year all-cause mortality [Glucose: OR 1.37 (95% CI 1.00-1.89); SHR: 1.27 (95% CI 0.91–1.78)]. In STEMI patients, ROC analysis showed that SHR performed better than glucose (AUC for glucose 0.633 versus AUC for SHR 0.692, P

Introduction: Acute myocardial infarction (MI) and acute ischaemic stroke (AIS) are leading causes of morbidity and mortality. There is scarce data examining the interplay between post-MI left ventricular systolic dysfunction (LVSD), with or without atrial fibrillation (AF), and subsequent AIS, especially in patients with milder degrees of LVSD (ejection fraction 40-49%). Evidence of an association would be helpful in developing new strategies of reducing AIS after MI. As such, we sought to study this relationship in a real-world population-based registry. Methods: This study involved linking national-level data from the Singapore Myocardial Infarction Registry with the Singapore Stroke Registry from 1st January 2007 to 31st December 2018. Both data sets have similar definitions for patient demographics. The ejection fraction (EF) and AF status were recorded during the MI episode. The outcome studied was the first instance of AIS that developed after the MI episode. We also studied the relationship between EF, AF and the severity of AIS as measured by the NIH Stroke Scale (NIHSS). Results: There were 64,512 patients available for analysis. The median age was 65.7 (IQR 56.1-76.5) and 69.5% were male. The median duration post-MI to develop AIS was 16.9 (IQR 1.6-46.1) months. There was an independent association between LVSD and the outcome of AIS (adjusted HR 1.18, 95% CI 1.10-1.27); this was evident even in mild forms of LVSD (adjusted HR 1.16, 95% CI 1.06-1.27). AF was not a statistically significant predictor of AIS in post-MI patients with LVSD. Amongst patients without AF, post-MI LVSD was associated with a more severe stroke and higher NIHSS. Conclusion: Post-MI LVSD is associated with the occurrence of subsequent AIS. Although this relationship was independent of AF status, patients with LVSD but no AF had suffered a more severe AIS. These findings support the need to develop effectives therapies to prevent AIS post-MI, especially among those with LVSD.

Background and Aim: The benefit of early coronary angiography (CAG) and revascularization in resuscitated out-of-hospital cardiac arrest (OHCA) is unclear. We evaluated the association between early CAG and clinical outcomes in these patients. Methods: Data on all resuscitated adult OHCA cases of cardiac etiology between 2011-2015 were extracted from the prospective Singapore Pan-Asian Resuscitation Outcomes Study and linked with data from the national database of cardiac procedures. The 30-day survival and neurological outcomes (good outcome defined as Cerebral Performance Category [CPC] 1 or 2) were compared between patients undergoing early CAG (within 1-calender day) and patients not undergoing early CAG. Inverse probability weighted estimator was used to adjust for propensity to perform early CAG and PCI. Results: Of 976 consecutive patients who survived to admission (mean age 64±13, 73.7% males), 401 (41.1%) patients underwent CAG and obstructive coronary artery disease (CAD) was present in 352 (87.8%), of whom 284 (70.8%) underwent revascularization. Patients who underwent early CAG (n=337[34.5%]) were significantly different compared to those who underwent delayed or no CAG (n=639[65.5%]) (Table 1). Early CAG and PCI patients had improved survival and better neurological outcomes (adjusted odds ratio [AOR] 3.806 [95% CI 1.675 - 8.648] and AOR 3.075 [95% CI 1.119 - 8.451]), compared to those without. The odds of survival decreased with epinephrine administration (AOR 0.357 [95% CI 0.199 - 0.640]), but increased with an initial shockable rhythm (AOR 6.587 [95% CI 3.659 - 11.861]). The rates of bleeding (2% vs 0%, p=0.300) and stroke (1.6% vs 1.9%, p=0.880) were not increased with early intervention. Conclusion: Early CAG and PCI after OHCA were associated with improved clinical outcomes after OHCA without increasing complications. Further studies are required to identify the characteristics of patients who would benefit most from this invasive strategy.

The Environmental Protection Agency (EPA) sets national ambient air quality standards (NAAQS) for six criteria pollutants and monitors attainment to these standards through a system of federally accepted analytical methods (FEMs or FRMs). Due to their cost and technical sophistication, FEM monitoring networks may be good for measuring air pollution at a regional spatial resolution but may not be appropriate for monitoring neighborhood-level resolution. While FEM networks are effective at monitoring regional scale pollution, literature indicates that pollution varies considerably at sub-regional and even neighborhood-or block-level spatial scales. Therefore, while a region may be in attainment with the NAAQS, local communities’ air quality may not be represented by the data collected through the FEM network. In fact, public health trends, uneven distribution of tree canopy, and socioeconomic data indicate that particular communities in Washington, DC may have a high risk for nonattainment despite the District being in compliance with federal measures of air quality. With the overarching goal of mitigating this potential environmental and public health issue, the George Washington University Sustainability living lab project, Fresh Air DC, is working to deploy low-cost high-density air monitoring systems with at least one sensor in each advisory neighborhood council (ANC) throughout the District. In this paper, we formulate the elements of a policy framework that can support the establishment of this system. Our research will involve a comparative analysis between two existing low-cost high-density systems, one deployed in California and brought forth by state legislation, and the Breathe London hyperlocal air quality monitoring network. This comparative analysis will demonstrate the role of effective policy systems in supporting the development and implementation of a low-cost high-density system in DC. Moreover, this analysis demonstrates the role of the proposed policy framework in supporting the new DC Sustainability Plan.

Background In ST-segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (PPCI), current oral P2Y12 platelet inhibitors do not provide maximal platelet inhibition at the time of reperfusion. Furthermore, administration of cangrelor prior to reperfusion has been shown in pre-clinical studies to reduce myocardial infarct (MI) size. Therefore, we hypothesize that cangrelor administered prior to reperfusion in STEMI patients will reduce the incidence of microvascular obstruction (MVO) and limit MI size in STEMI patients treated with PPCI. Methods The platelet inhibition to target reperfusion injury (PITRI) trial, is a phase 2A, multi-center, double-blinded, randomized controlled trial, in which 210 STEMI patients will be randomized to receive either an intravenous (IV) bolus of cangrelor (30 μg/kg) followed by a 120-minute infusion (4 μg/kg/min) or matching saline placebo, initiated prior to reperfusion (NCT03102723). Results The study started in October 2017 and the anticipated end date would be July 2020. The primary end-point will be MI size quantified by cardiovascular magnetic resonance (CMR) on day 3 post-PPCI. Secondary endpoints will include markers of reperfusion, incidence of MVO, MI size, and adverse left ventricular remodeling at 6 months, and major adverse cardiac and cerebrovascular events. Summary The aim of the PITRI trial is to assess whether cangrelor administered prior to reperfusion would reduce acute MI size and MVO, as assessed by CMR.

Bilateral acetabular fractures have been documented in the setting of high-energy trauma, but few reports regarding atraumatic bilateral acetabular fractures exist. The following is a case report of bilateral insufficiency acetabular fractures which occurred acutely in the absence of trauma in a 49-year-old female. The case highlights the importance of perioperative awareness of those patients at significant risk of insufficiency fractures and offers a relatively elegant, less invasive solution for early mobilization in the context of acetabula insufficiency fractures.

Somatostatin receptor 2 (SSTR2) is frequently overexpressed on several types of solid tumors, including neuroendocrine tumors and small-cell lung cancer. Peptide agonists of SSTR2 are rapidly internalized upon binding to the receptor and linking a toxic payload to an SSTR2 agonist is a potential method to kill SSTR2-expressing tumor cells. Herein, we describe our efforts towards an efficacious SSTR2-targeting cytotoxic conjugate; examination of different SSTR2-targeting ligands, conjugation sites, and payloads led to the discovery of 22 (PEN-221), a conjugate consisting of microtubule-targeting agent DM1 linked to the C-terminal side chain of Tyr3–octreotate. PEN-221 demonstrates in vitro activity which is both potent (IC50 = 10 nM) and receptor-dependent (IC50 shifts 90-fold upon receptor blockade). PEN-221 targets high levels of DM1 to SSTR2-expressing xenograft tumors, which has led to tumor regressions in several SSTR2-expressing xenograft mouse models. The safety and efficacy of PEN-221 is currently ...

Small cell lung cancer (SCLC) is an aggressive neuroendocrine carcinoma with a 95% mortality rate with no improvement to treatment in decades, and new therapies are desperately needed. PEN-221 is a miniaturized peptide–drug conjugate (∼2 kDa) designed to target SCLC via a Somatostatin Receptor 2 (SSTR2)–targeting ligand and to overcome the high proliferation rate characteristic of this disease by using the potent cytotoxic payload, DM1. SSTR2 is an ideal target for a drug conjugate, as it is overexpressed in SCLC with limited normal tissue expression. In vitro, PEN-221 treatment of SSTR2-positive cells resulted in PEN-221 internalization and receptor-dependent inhibition of cellular proliferation. In vivo, PEN-221 exhibited rapid accumulation in SSTR2-positive SCLC xenograft tumors with quick clearance from plasma. Tumor accumulation was sustained, resulting in durable pharmacodynamic changes throughout the tumor, as evidenced by increases in the mitotic marker of G2–M arrest, phosphohistone H3, and increases in the apoptotic marker, cleaved caspase-3. PEN-221 treatment resulted in significant antitumor activity, including complete regressions in SSTR2-positive SCLC xenograft mouse models. Treatment was effective using a variety of dosing schedules and at doses below the MTD, suggesting flexibility of dosing schedule and potential for a large therapeutic window in the clinic. The unique attributes of the miniaturized drug conjugate allowed for deep tumor penetration and limited plasma exposure that may enable long-term dosing, resulting in durable tumor control. Collectively, these data suggest potential for antitumor activity of PEN-221 in patients with SSTR2-positive SCLC.

Hypercholesterolemia has been identified as a risk factor for Alzheimer's disease. In this study, rabbits were fed either a cholesterol diet or normal chow diet for 24 months. At endpoint, in vivo MRI was performed at the field strength of 3 Tesla using fast imaging employing steady state acquisition without (FIESTA) or with susceptibility-weighted post-processing (SWI-FIESTA) and susceptibility-weighted imaging with multi-echo acquisition (SWAN). This imaging revealed signal voids/hypointensities throughout the cortex, sub-cortex, and hippocampus of cholesterol-fed animals compared to control animals. Quantitative image analysis corroborated these qualitative findings and highlighted that SWI processing of FIESTA images significantly improved the detectability of plaques (p < 0.05). A beta immunostaining and Prussian blue staining for iron demonstrated that the voids in MR images corresponded to iron-laden A beta-positive plaques. This study demonstrates non-invasive in vivo visualization of A beta plaques in a diet-induced large animal model of Alzheimer's disease. This work lays the foundation for future work focusing on longitudinal monitoring of plaque formation in this model and the effects of diet or drug interventions.

Small interfering RNA (siRNA) therapeutics have potential advantages over traditional small molecule drugs such as high specificity and the ability to inhibit otherwise "undruggable" targets. However, siRNAs have short plasma half-lives in vivo, can induce a cytokine response, and show poor cellular uptake. Formulating siRNA into nanoparticles offers two advantages: enhanced siRNA stability against nuclease degradation beyond what chemical modification alone can provide; and improved site-specific delivery that takes advantage of the enhanced permeability and retention (EPR) effect. Existing delivery systems generally suffer from poor delivery to tumors. Here we describe the formation and biological activity of polymeric nanopharmaceuticals (PNPs) based on biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) conjugated to siRNA via an intracellular cleavable disulfide linker (PLGA-siRNA). Additionally, these PNPs contain (1) PLGA conjugated to polyethylene glycol (PEG) for enhanced pharmacokinetics of the nanocarrier; (2) a cation for complexation of siRNA and charge compensation to avoid high negative zeta potential; and (3) neutral poly(vinyl alcohol) (PVA) to stabilize the PNPs and support the PEG shell to prevent particle aggregation and protein adsorption. The biological data demonstrate that these PNPs achieve prolonged circulation, tumor accumulation that is uniform throughout the tumor, and prolonged tumor-specific knockdown. PNPs employed in this study had no effect on body weight, blood cell count, serum chemistry, or cytokine response at doses10 times the effective dose. PNPs, therefore, constitute a promising solution for achieving durable siRNA delivery and gene silencing in tumors.

This article examines the occupational aspirations of 15-year olds. [The authors] first determine the drivers of occupational aspirations before comparing aspirations with actual employment outcomes a decade later. Whilst actual jobs held at age 25 years do not quite meet young people's initial aspirations, they compare favourably with the overall job distribution of the Australian workforce, particularly for young women. It is suggested that these positive outcomes reflect the higher education levels of young cohorts, compared to older ones. One likely reason why young women exceed young men regarding occupational status is the higher proportion of women completing university studies.

This article examines the importance of schools relative to individual characteristics in explaining Tertiary Entrance Rank scores, using Longitudinal Surveys of Australian Youth data. The school characteristics explain around 20 per cent of the variance in Tertiary Entrance Rank scores, with the measured school characteristics explaining around 7 percentage points, indicating that idiosyncratic factors—which we interpret as reflecting schools' ethos—dominate. School sector is an important explanator; whilst the government, independent and Catholic systems all contain ‘good’ schools, schools that have low Tertiary Entrance Rank scores, after controlling for individual characteristics, are dominated by the government sector.

The issue addressed by this article is whether there is an interaction between school ‘quality’ and students' socioeconomic status. That is, is a school that is of ‘high quality’ for high socioeconomic status students as effective for students from a low socioeconomic background? The answer is that a school that is of ‘high-quality’ benefits all students in terms of completion of Year 12, but more so for the most vulnerable of students: those who have low academic achievement at age 15 years in addition to coming from a low socioeconomic status background.

The thermal and flammability properties of halogen-free flame retardants, calcium borate and intumescent ammonium polyphosphate, were evaluated on epoxy/glass fiber composites. The evolved volatile products under thermal stresses were analyzed accordingly, and the thermal decomposition of the composites was studied. It was determined that ammonium polyphosphate and calcium borate releases water vapor and carbon dioxide during their thermal decomposition, as a method to overcome the fire. Ammonium polyphosphate that achieved the V-0 rating at 5 vol% loading had showed better fire resistance than calcium borate that failed to achieve any rating even at high loading of 20 vol%. However, the calcium borate had recorded higher residual content. The combination of 1 vol% calcium borate and 4 vol% ammonium polyphosphate exhibited a synergistic performance by mass producing more char as a protection for the composites. Nevertheless, this synergism was not observed with the other combination, which comprised a 50:50 ratio of ammonium polyphosphate–calcium borate.

PurposeThe aim of this paper is to compare the performance of area‐based vs individual‐level measures of socioeconomic status (SES).Design/methodology/approachUsing data from the longitudinal surveys of Australian youth (LSAY), a multidimensional measure of individual SES is created. This individual measure is used to benchmark the relative usefulness of socio‐economic indexes for areas (SEIFA), a geographic set of measures often used in Australia to assess the SES of individuals. Both measures are compared in terms of classification bias. The effects of using the different SES measures on participation in post‐compulsory education are examined.FindingsSEIFA measures perform satisfactorily with regard to the aggregate measurement of SES. However, they perform poorly when their use is aimed at channelling resources toward disadvantaged individuals. It is at the individual level that the analysis reveals the shortcomings of area‐based SES measures.Research limitations/implicationsWhile region based measures are relatively easy to collect and utilise, we suggest that they hide significant SES heterogeneity within regional districts. Hence, the misclassification resulting from the use of regional measures to direct support for low SES groups creates a risk for resource misallocations.Originality/valueThe finding that region‐based measures are subject to significant misclassification has important research and policy implications. Given the increasing availability of individual‐level administrative data, the paper suggests that such data be used as a substitute for geographic SES measures in categorising the SES of individuals.

We examined the biological importance of Sertoli cell androgen receptor (AR) genomic interaction, using a Cre-loxP approach to selectively disrupt the AR DNA-binding domain (AR-DBD). Sertoli cell (SC)-specific transgenic Abpa or AMH promoters targeted Cre-mediated inframe excision of mouse Ar exon-3, encoding the AR-DBD second zinc-finger (ZF2), generating SC-specific mutant AR(DeltaZF2) lines designated Abp.SCAR(DeltaZF2) and AMH.SCAR(DeltaZF2), respectively. Both SCAR(DeltaZF2) lines produced infertile males exhibiting spermatogenic arrest, despite normal SC numbers and immunolocalized SC nuclear AR. Adult homozygous TgCre((+/+)) SCAR(DeltaZF2) or double-TgCre((+/-)) Abp/AMH.SCAR(DeltaZF2) males displayed equivalent small testes 30% of normal size, representing maximal Cre-loxP-disruption of Sertoli AR function. Hemizygous TgCre((+/-)) vs. homozygous TgCre((+/+)) Abp.SCAR(DeltaZF2) testes were larger (47% normal size) with more postmeiotic development, indicating dose-dependent Cre-mediated disruption of SC-specific AR-DBD activity. SCAR(DeltaZF2) males exhibited adult Leydig cell hypertrophy but normal serum testosterone levels. Sertoli cell-specific Rhox5 and Spinlw1 transcription, regulated by divergent or classical androgen-response elements, respectively, were both decreased in postnatal SCAR(DeltaZF2) vs. control testes, demonstrating SC-specific AR-DBD function as early as postnatal d 5. However, Rhox5 expression declined dose-dependently, whereas Spinlw1 expression increased, in adult TgCre((+/-)) and TgCre((+/+)) SCAR(DeltaZF2) testes, revealing differential temporal control for distinct AR-regulated transcripts. Androgen-repressed Ngfr was not up-regulated in SCAR(DeltaZF2) testes, suggesting maintenance of a nonclassical mechanism independent of AR-DBD. Thus, our unique SCAR(DeltaZF2) paradigm provided dose-dependent Cre-mediated disruption of testicular development and gene expression revealing that the AR-DBD is essential for SC function and postmeiotic spermatogenesis. Nongenomic or AR-DBD-independent pathways appear secondary or play no major independent role in SC function.

We have characterized the in vivo actions of human wild-type FSH receptor (FSHR) overexpressed in Sertoli cells of transgenic (Tg) mice ( TgFSHRwt) compared with transgenic overexpression of the human activated mutant FSHR*D567G ( TgFSHR*D567G). Testicular TgFSHRwt expression significantly elevated specific FSH binding (>2-fold, P < 0.01) relative to nontransgenic testes, similar to increased FSH binding in TgFSHR*D567G testes. Isolated TgFSHRwt Sertoli cells exhibited higher FSH-stimulated cAMP levels compared with non- Tg or TgFSHR*D567G cells but did not display the elevated FSH-independent basal cAMP levels found in TgFSHR*D567G Sertoli cells. Furthermore, Sertoli cell overexpression of TgFSHR*D567G but not TgFSHRwt allowed promiscuous cAMP responses to human chorionic gonadotropin (300 IU/ml) and TSH (30 mIU/ml), demonstrating increased constitutive signaling and altered glycoprotein hormone specificity via the intracellular D567G substitution rather than FSHR overexpression. Despite elevating Sertoli cell FSH sensitivity, overexpression of TgFSHRwt had no detectable effect upon normal testis function and did not stimulate Sertoli and germ cell development in testes of gonadotropin-deficient hypogonadal ( hpg) mice, in contrast to the increased meiotic and postmeiotic germ cell development in TgFSHR*D567G hpg testes. Increased steroidogenic potential of TgFSHR*D567G hpg testes was demonstrated by elevated Cyp11a1 and Star expression, which was not detected in TgFSHRwt hpg testes. Androgen-regulated and Sertoli cell-specific Rhox5 gene expression was increased in TgFSHR*D567G but not TgFSHRwt hpg testes, providing evidence of elevated LH-independent androgen activity due to mutant FSHR*D567G. Hence, transgenic FSHR overexpression in Sertoli cells revealed that the D567G mutation confers autonomous signaling and steroidogenic activity in vivo as well as promiscuous glycoprotein hormone receptor activation, independently of FSHR overexpression alone.

There is increasing interest in the usefulness of block copolymer micelles as drug delivery vehicles. However, their subcellular distribution has not been explored extensively, mostly because of the lack of adequately labeled block copolymers. In a previous study, we showed that fluorescently labeled block copolymer micelles entered living cells and co-localized with cytoplasmic organelles selectively labeled with fluorescent dyes. The details of the observed co-localizations were, however, limited by the resolution of the fluorescence approach, which is ca. 500 nm. Using transmission electron microscopy (TEM), we established time- and concentration-dependent subcellular distributions of gold-labeled micelles within human embryonic kidney (HEK 293) cells and human lung carcinoma (A549) cells. Gold particles were incorporated into poly(4-vinylpyridine)-block-poly(ethylene oxide) (P4VP21-b-PEO45) micelles. Data from dynamic light scattering (DLS) and TEM analyses revealed that the sizes of the gold particles ranged from 4 to 8 nm. The cells survived up to 24 h in the presence of low gold-labeled micelle concentrations (0.73 microg/mL), but cell death occurred at higher concentrations (i.e., kidney cells are more susceptible than lung cells). Over 24 h periods of equivalent exposure, lung cells internalized significantly more gold-incorporated micelles than kidney cells. Although micelles were added to the cell culture media as dispersed colloidal particles, the presence of serum in these media caused aggregation. These aggregates occurred mainly close to the cell plasma membrane at early times (5-10 min); however, at later times (24 h) aggregated particles were seen inside endosomes and lysozomes. Thus, gold-incorporated (labeled) micelles can serve as a valuable extension of the fluorescence approach to visualizing the localization of micelles in subcellular compartments, improving the resolution by at least 20-fold.

Various hormone replacement regimens and delivery systems have been developed ; however, there is still a need for additional, easily controllable and biocompatible systems. We have developed and characterized biocompatible polycaprolactone-block-poly(ethylene oxide) (PCL-b-PEO) micelles for the delivery of 17beta-estradiol (E2) and investigated their loading and release properties using fluorescence spectroscopy. The micelles are spherical aggregates that range in size from 20 to 40 nm, as determined by both transmission electron microscopy and dynamic light scattering. A high loading efficiency for E2 of up to 96%, as well as a high drug loading capacity of up to 4000 molecules of E2 per micelle (equivalent to 190% (w/w)), is obtainable. In addition, the E2 loading and release can be controlled by modifying the block length of the polycaprolactone core and the initial estradiol concentration. The release of E2 from the micelles showed a biphasic profile under perfect sink conditions: there is an initial burst release, followed by a slow and prolonged release for up to 5 days, until complete release is achieved. The release of E2 from the micelles was shown to be diffusional, as shown by the linearity of the release as a function of the square root of time. Approximate diffusion coefficients of the order of 10(-17) cm2/s were obtained. In vitro and in vivo experiments confirmed that the biological activity of E2 was retained after preparation of the micelles. This micelle carrier could serve as a versatile and efficient nanodelivery system for steroids and other poorly water soluble drugs that require solubilizing agents for delivery.

Block copolymer vesicles can be prepared in solution from a variety of different amphiphilic systems. Polystyrene-block-poly(acrylic acid), polystyrene-block-poly(ethylene oxide), and many other block copolymer systems can produce vesicles of a wide range of sizes; those in the range of 100–1000 nm have been explored extensively. Different factors, such as the absolute and relative block lengths, the presence of additives (ions, homopolymers, and surfactants), the water content in the solvent mixture, the nature and composition of the solvent, the temperature, and the polydispersity of the hydrophilic block, provide control over the types of vesicles produced. Their high stability, resistance to many external stimuli, and ability to package both hydrophilic and hydrophobic compounds make them excellent candidates for use in the medical, pharmaceutical, and environmental fields. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 923–938, 2004

Here we describe the discovery and the structure of PEN-221, a somatostatin receptor 2 (SSTR2) targeting peptide conjugated to DM1. PEN-221 is the first clinical compound from Tarveda’s Pentarin platform, which utilizes miniaturized drug conjugates that diffuse rapidly and deeply into solid tumors. Antibody drug conjugates (ADCs) have garnered a significant amount of attention in their ability to direct cytotoxic drugs to cancer cells; however, the efficacy of ADCs in solid tumors is limited by the slow diffusion of such large molecules through solid tumor tissue. Pentarins are designed to improve the efficacy of targeted therapies through effective tumor cell targeting and enhanced tumor penetration. SSTR2, a GPCR overexpressed in multiple types of neuroendocrine tumors, including small cell lung cancers, internalizes rapidly upon agonist stimulation, making it an ideal vector for delivering cytotoxic payloads. Examination of a variety of SSTR2 targeting ligands, as well as several potential conjugation sites, led to the identification of the C-terminal side chain of [Tyr3]-octreotate amide as the best conjugation site for a lipophilic payload. The use of DM1 as a payload afforded superior receptor affinity and receptor internalization when compared to other similarly potent microtubule-targeting agents. In vitro studies show that PEN-221 has receptor-dependent cytotoxic effects, and preclinical studies demonstrate PEN-221 induces tumor regression in several SSTR2 expressing xenograft models. Citation Format: Brian H. White, Patrick Bazinet, Kerry Whalen, Michelle DuPont, James M. Quinn, Rossitza Alargova, Tsun Au Yeung, Adam Brockman, James Gifford, Haley Oller, Kristina Kriksciukaite, Charles-Andre Lemelin, Patrick Lim Soo, Benoit Moreau, Samantha Perino, Gitanjali Sharma, Rajesh Shinde, Beata Sweryda-Krawiec, Mary Simcox, Richard Wooster, Mark T. Bilodeau. Discovery of PEN-221, an SSTR2-targeting maytansinoid conjugate with potent activity in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 39. doi:10.1158/1538-7445.AM2017-39

Hydrolysis of benzaldehyde dimethyl acetal 1 in aqueous acid is slowed down greatly by cyclodextrins (CDs): α-CD, β-CD, hp-β-CD (hydroxypropyl-β-cyclodextrin) and γ-CD. The variations of the observed first-order rate constants (kobs) with [CD] exhibit saturation behaviour, consistent with 1∶1 binding between 1 and the CDs. In the case of β-CD and hp-β-CD, the binding is relatively strong and the CD-bound acetal is unreactive. In contrast, binding of the acetal by α-CD and γ-CD is much weaker, but only with α-CD does the CD-bound form show significant reactivity. The four CD-mediated reactions have been evaluated as probe reactions for determining dissociation constants of {CD– ‘guest’} complexes. In this approach, added guests attenuate the retarding effect of CD–substrate binding and cause an increase in the rate of acetal hydrolysis. The method works well for aliphatic alcohols and ketones binding to β-CD and hp-β-CD, but it is less successful with α-CD because of the shallow dependence of kobs on [α-CD] in the probe reaction. With γ-CD, the approach is not applicable at all, because added guests cause a further reduction in the rate of acetal hydrolysis, not an increase. Various implications of these findings are discussed.

Sham feeding has been shown to hasten the return of GI function following colorectal surgery, before the advent of enhanced recovery after surgery protocols. Few data exist regarding the efficacy of sham feeding in the modern era, with rapid postoperative feeding.We sought to perform a meta-analysis on the effect of sham feeding in colorectal surgery, with a separate analysis on trials that used rapid postoperative feeding.Cochrane, MEDLINE, EMBASE, Scopus, and PubMed were searched by using the terms gum OR sham feeding OR chew AND (colorect OR resect).All studies were randomized controlled trials (in any language) performed on adults, comparing standard care with gum chewing following colorectal resection. From 439 citations, 10 articles were included.The intervention was sham feeding by means of gum chewing.The outcome measures were time to return of flatus, time to first bowel movement, complication rates, length of hospital stay, readmission rates, and reoperation rates.Ten randomized controlled trials (n = 612) were included. Sham feeding resulted in a reduction in time to flatus of 31 minutes (p = 0.003) and time to first bowel movement of 30 minutes (p = 0.05). Sham feeding also resulted in a reduction in length of stay by 0.5 days (p = 0.007), and a reduction in complication rates (relative risk = 0.687, p = 0.017), although this appeared to be associated with publication bias. Analysis of trials that used rapid postoperative feeding (n = 282) revealed no difference in postoperative GI function.This review was limited by the heterogeneity of postoperative feeding regimes, in addition to limited reporting by trials of postoperative morbidity.Sham feeding following colorectal surgery is safe, results in small improvements in GI recovery, and is associated with a reduction in the length of hospital stay. It confers no advantage if patients are placed on a rapid postoperative feeding regime.

To determine whether sham feeding with chewing gum improved gastrointestinal recovery after colorectal resection surgery, in the presence of routine postoperative feeding.Sham feeding with chewing gum has been shown to accelerate the return of gut function after colorectal surgery. This study sought to determine whether sham feeding with gum, after colorectal resection, accelerates return of gastrointestinal function in patients on a rapid feeding enhanced recovery program.A randomized "two armed" controlled clinical trial was performed. Equal groups of open and laparoscopic colorectal resection surgical patients were recruited. Patients in the intervention arm received chewing gum 4 times a day postoperatively. All patients in the trial were placed on an established, standardized Enhanced Recovery After Surgery program. The primary outcome was time to return of gut function, assessed by time to flatus and first bowel motion. Secondary outcomes were time to tolerate diet, symptoms of ileus in the form of nausea, vomiting and distension, pain as assessed by analgesic consumption and visual analogue scales, complications, and length of hospital stay.A total of 161 patients were recruited. Postoperative morbidity was equivalent between groups, with no complications related to gum chewing. There was no difference between groups with respect to the primary outcomes of time to flatus and bowel motion. There was less perception of pain in the intervention group on days 2 to 5, and no difference with respect to all other secondary outcomes.Sham feeding with gum, after open and laparoscopic colorectal resectional surgery is safe, but does not hasten the return of gastrointestinal function in patients who receive accelerated postoperative feeding. (ACTRN12607000538448).