Synthesis of Bicyclo[1.1.0]butanes from Iodo-Bicyclo[1.1.1]pentanes.

We describe a two-step process for the synthesis of substituted bicyclo[1.1.0]butanes. A photo-Hunsdiecker reaction generates iodo-bicyclo[1.1.1]pentanes under metal-free conditions at room temperature. These intermediates react with nitrogen and sulfur nucleophiles to afford substituted bicyclo[1.1.0]butane products.

Substituted diaryl ether compounds as retinoic acid-related orphan Receptor-γt (RORγt) agonists.

The discovery of a series of substituted diarylether compounds as retinoic acid related orphan receptor γt (RORγt) agonists is described. Compound 1 was identified from deck mining as a RORγt agonist. Hit-to-lead optimization led to the identification of lead compound 5, which possesses improved potency (10x). Extensive SAR exploration led to the identification of a potent and selective compound 22, that demonstrated an improved pharmacokinetic profile and a dose-dependent pharmacodynamic response. However, when dosed in a MC38 syngeneic tumor model, no evidence of efficacy was observed. ©2020 Elsevier Science Ltd. All rights reserved.

The Longitudinal and Cross-Sectional Associations of Grief and Complicated Grief With Sleep Quality in Older Adults.

OBJECTIVE/BACKGROUND: About 15% of grievers experience complicated grief. We determined cross-sectional and longitudinal relations of grief and complicated grief with sleep duration and quality in the general population of elderly adults. PARTICIPANTS: We included 5,421 men and women from the prospective population-based Rotterdam Study. METHODS: The Inventory of Complicated Grief was used to define grief and complicated grief. We assessed sleep with the Pittsburgh Sleep Quality Index. RESULTS: After 6 years, 3,511 (80% of survivors) underwent the follow-up interview. Complicated grief was cross-sectionally associated with shorter sleep duration and lower sleep quality. These associations were explained by the presence of depressive symptoms. The prospective analyses showed that sleep duration and sleep quality did not decline further during follow-up of persons who experienced grief or complicated grief. CONCLUSION: In community-dwelling, middle-aged and older adults, persons with normal and complicated grief had both a shorter sleep duration and a lower sleep quality, mainly explained by depressive symptoms. However, prospective analyses showed that sleep quality and sleep duration do not decline further in persons with normal grief and complicated grief.

Prolonged Grief and Cognitive Decline: A Prospective Population-Based Study in Middle-Aged and Older Persons.

OBJECTIVE: Bereavement can result in unresolved and prolonged grief, often termed prolonged grief disorder (PGD). The impact of PGD on cognitive functioning is poorly understood. The aim of the study was to compare the cognitive decline, assessed by repeated measures of different cognition domains, between persons with normal and PGD and a non-grieving reference population in a 7-year follow-up study. METHODS: The study sample comprised 3126 non-demented persons, mean age: 64 years, of the Rotterdam Study. Participants were classified into three groups: no grief (reference group, N = 2,582), normal grief (N = 418), and prolonged grief disorder (N = 126). Participants were assessed with the Complicated Grief Inventory and underwent cognitive testing (Mini-Mental State Examination [MMSE], Letter-Digit Substitution test, Stroop test, Word fluency task, Word learning test). Analyses were adjusted for baseline cognition and depressive symptoms; persons with major depressive disorders were excluded. RESULTS: Compared with the reference group, participants with PGD showed a decrease in global cognitive function, MMSE scores, and World learning test (immediate and delayed) over time. Participants with normal grief did not show a stronger cognitive decline in any of cognitive tests than the reference group. CONCLUSIONS: Participants with PGD showed a stronger cognitive decline than the reference group during 7 years of follow-up. This suggests that PGD is a risk factor for cognitive decline, but this study cannot detect the psychobiological mechanism underlying this longitudinal association.

Macrocyclic pyrrolobenzodiazepine dimers as antibody-drug conjugate payloads.

Macrocyclic pyrrolobenzodiazepine dimers were designed and evaluated for use as antibody-drug conjugate payloads. Initial structure-activity exploration established that macrocyclization could increase the potency of PBD dimers compared with non-macrocyclic analogs. Further optimization overcame activity-limiting solubility issues, leading to compounds with highly potent (picomolar) activity against several cancer cell lines. High levels of in vitro potency and specificity were demonstrated with an anti-mesothelin conjugate.

The Impact of Complicated Grief on Diurnal Cortisol Levels Two Years After Loss: A Population-Based Study.

OBJECTIVE: Few studies have focused on the effect of complicated grief-unresolved and prolonged grief-on the neuroendocrine systems. The present study examined the association of complicated grief and normal grief with the diurnal cortisol patterns in a large population-based study. METHODS: This study was set in the Rotterdam Study and comprised 2084 persons aged older than 55 years (mean [SD] age, 64.9 [5.5] years). Participants were assessed with the Complicated Grief Inventory and classified into no grief (n = 1922), normal grief (n = 131), or complicated grief (n = 31) if they experienced the loss in the past 2 years. Saliva samples were collected to measure cortisol levels. Morning cortisol and summary measures (area under the curve and the slope) were studied to account for the diurnal pattern of cortisol. Persons with depressive disorders were excluded, and analyses were additionally adjusted for depressive symptoms. RESULTS: Compared to normal grievers, participants with complicated grief showed lower levels of morning cortisol (11.26 vs 15.51 nmol/L; difference, -4.24; 95% confidence interval [CI] = -7.87 to -0.62; p = .022), and lower levels of overall diurnal cortisol (6.89 vs 8.98 nmol/L; difference, -2.09; 95% CI = -3.81 to -0.37; p = .017). No difference was observed in slope between both groups. Participants with complicated grief also showed lower levels of morning cortisol than the nongrievers (11.26 vs 14.71; difference, -3.46; 95% CI = -6.78 to -0.13; p = .042). In contrast, cortisol secretion patterns did not differ between persons with normal grief and nongrieving controls. CONCLUSIONS: Participants with complicated grief showed low levels of morning cortisol and low overall diurnal cortisol levels characteristic for a chronic stress reaction.

Markers of cerebral small vessel disease and severity of depression in the general population.

The vascular depression hypothesis postulates that cerebral small vessel disease can cause or exacerbate depression in elderly persons. Numerous studies explored the association of imaging markers of cerebral small vessel disease including white matter lesions (WMLs) and lacunar infarcts with depressive symptoms or disorders. However, cerebral microbleeds have not been tested in depression. In the current study, we aimed to explore the association of WMLs, lacunar infarcts and cerebral microbleeds with depression continuum in a large population-based sample, the Rotterdam Study. Study population consisted of 3799 participants (aged 45 or over) free of dementia. WML volumes, lacunar infarcts and cerebral microbleeds were measured with brain magnetic resonance imaging. Depressive symptoms, depressive disorders and co-morbid anxiety disorders were assessed with validated questionnaires and clinical interview. WML volumes and lacunar infarcts were associated with depressive symptoms and disorders. Cerebral microbleeds, especially in deep or infratentorial brain regions, were related to depressive disorders only. Our results indicate that WMLs and lacunar infarcts might be non-specific vascular lesions seen in depressive symptoms and disorders. Association of cerebral microbleeds with more severe forms of depression may indicate impaired brain iron homeostasis or minor episodes of cerebrovascular extraversion, which may play a role in depression etiology.

Discovery of potent heterodimeric antagonists of inhibitor of apoptosis proteins (IAPs) with sustained antitumor activity.

The prominent role of IAPs in controlling cell death and their overexpression in a variety of cancers has prompted the development of IAP antagonists as potential antitumor therapies. We describe the identification of a series of heterodimeric antagonists with highly potent antiproliferative activities in cIAP- and XIAP-dependent cell lines. Compounds 15 and 17 further demonstrate curative efficacy in human melanoma and lung cancer xenograft models and are promising candidates for advanced studies.

Discovery of tetrahydroisoquinoline-based bivalent heterodimeric IAP antagonists.

Bivalent heterodimeric IAP antagonists that incorporate (R)-tetrahydroisoquinoline in the P3' subunit show high affinity for the BIR2 domain and demonstrated potent IAP inhibitory activities in biochemical and cellular assays. Potent in vivo efficacy was observed in a variety of human tumor xenograft models. The bivalent heterodimeric molecule 3 with a P3-P3' benzamide linker induced pharmacodynamic markers of apoptosis and was efficacious when administered intravenously at a dose of 1mg/kg to mice harboring A875 human melanoma tumors. Analog 5, with a polyamine group incorporated at the P2' thiovaline side chain exhibited antiproliferative activity against the P-gp expressing HCT116/VM46 cell line.

Antibody-drug conjugates: current status and future directions.

Antibody-drug conjugates (ADCs) aim to take advantage of the specificity of monoclonal antibodies (mAbs) to deliver potent cytotoxic drugs selectively to antigen-expressing tumor cells. Despite the simple concept, various parameters must be considered when designing optimal ADCs, such as selection of the appropriate antigen target and conjugation method. Each component of the ADC (the antibody, linker and drug) must also be optimized to fully realize the goal of a targeted therapy with improved efficacy and tolerability. Advancements over the past several decades have led to a new generation of ADCs comprising non-immunogenic mAbs, linkers with balanced stability and highly potent cytotoxic agents. Although challenges remain, recent clinical success has generated intense interest in this therapeutic class.

Silent brain infarcts: a cause of depression in the elderly?

The present study included 1047 elderly participants. At baseline, brain magnetic resonance imaging (MRI) was performed to detect infarcts and white matter lesions; further, depressive disorders were assessed. Participants were followed up during 3.6 years to determine incident and recurrent depression. We found an increased risk of recurrent depression associated with silent brain infarcts.

Pyrazole and pyrimidine phenylacylsulfonamides as dual Bcl-2/Bcl-xL antagonists.

5-Butyl-1,4-diphenyl pyrazole and 2-amino-5-chloro pyrimidine acylsulfonamides were developed as potent dual antagonists of Bcl-2 and Bcl-xL. Compounds were optimized for binding to the I88, L92, I95, and F99 pockets normally occupied by pro-apoptotic protein Bim. An X-ray crystal structure confirmed the proposed binding mode. Observation of cytochrome c release from isolated mitochondria in MV-411 cells provides further evidence of target inhibition. Compounds demonstrated submicromolar antiproliferative activity in Bcl-2/Bcl-xL dependent cell lines.

Identification of a phenylacylsulfonamide series of dual Bcl-2/Bcl-xL antagonists.

A series of phenylacylsulfonamides has been prepared as antagonists of Bcl-2/Bcl-xL. In addition to potent binding affinities for both Bcl-2 and Bcl-xL, these compounds were shown to induce classical markers of apoptosis in isolated mitochondria. Overall weak cellular potency was improved by the incorporation of polar functionality resulting in compounds with moderate antiproliferative activity.

Involvement of several transcriptional regulators in the differential expression of tfd genes in Cupriavidus necator JMP134.

Cupriavidus necator JMP134 has been extensively studied because of its ability to degrade chloroaromatic compounds, including the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 3-chlorobenzoic acid (3-CB), which is achieved through the pJP4-encoded chlorocatechol degradation gene clusters: tfdCIDIEIFI and tfdDIICIIEIIFII. The present work describes a different tfd-genes expression profile depending on whether C. necator cells were induced with 2,4-D or 3-CB. By contrast, in vitro binding assays of the purified transcriptional activator TfdR showed similar binding to both tfd intergenic regions; these results were confirmed by in vivo studies of the expression of transcriptional lacZ fusions for these intergenic regions. Experiments aimed at investigating whether other pJP4 plasmid or chromosomal regulatory proteins could contribute to the differences in the response of both tfd promoters to induction by 2,4-D and 3-CB showed that the transcriptional regulators from the benzoate degradation pathway, CatR1 and CatR2, affected 3-CB- and 2,4-D-related growth capabilities. It was also determined that the ISJP4-interrupted protein TfdT decreased growth on 3-CB. In addition, an ORF with 34% amino acid identity to IclR-type transcriptional regulator members and located near the tfdII gene cluster module was shown to modulate the 2,4-D growth capability. Taken together, these results suggest that tfd transcriptional regulation in C. necator JMP134 is far more complex than previously thought and that it involves proteins from different transcriptional regulator families.

Involvement of several transcriptional regulators in the differential expression of tfd genes in Cupriavidus necator JMP134

Cupriavidus necator JMP134 has been extensively studied because of its ability to degrade chloroaromatic compounds, including the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 3-chlorobenzoic acid (3-CB), which is achieved through the pJP4-encoded chlorocatechol degradation gene clusters: tfdCIDIEIFI and tfdDIICIIEIIFII. The present work describes a different tfd-genes expression profile depending on whether C. necator cells were induced with 2,4-D or 3-CB. By contrast, in vitro binding assays of the purified transcriptional activator TfdR showed similar binding to both tfd intergenic regions; these results were confirmed by in vivo studies of the expression of transcriptional lacZ fusions for these intergenic regions. Experiments aimed at investigating whether other pJP4 plasmid or chromosomal regulatory proteins could contribute to the differences in the response of both tfd promoters to induction by 2,4-D and 3-CB showed that the transcriptional regulators from the benzoate degradation pathway, CatR1 and CatR2, affected 3-CB- and 2,4-D-related growth capabilities. It was also determined that the ISJP4-interrupted protein TfdT decreased growth on 3-CB. In addition, an ORF with 34% amino acid identity to IclR-type transcriptional regulator members and located near the tfdII gene cluster module was shown to modulate the 2,4-D growth capability. Taken together, these results suggest that tfd transcriptional regulation in C. necator JMP134 is far more complex than previously thought and that it involves proteins from different transcriptional regulator families (AU)

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