Influence of transducer pressure and examiner experience on muscle active shear modulus measured by shear wave elastography

INTRODUCTION

This study examined the effects of ultrasound transducer pressure and examiner experience on the biceps femoris long head and semitendinosus muscle active shear modulus in healthy individuals (n = 28).

METHODS

Active shear modulus was assessed using shear wave elastography at 20% of knee flexor maximal voluntary isometric contraction. Examiners with different experience levels measured the muscles' shear modulus with three pressure levels: mild, moderate, and hard.

RESULTS

A main effect of transducer pressure was found for both biceps femoris long head (p < 0.001; η2p = 0.314) and semitendinosus muscles (p < 0.001; η2p = 0.280), whereas differences were found between mild-moderate (biceps femoris long head: p = 0.013, d = 0.23; semitendinosus: p = 0.024, d = 0.25), and mild-hard pressures (biceps femoris long head: p = 0.001, d = 0.47; semitendinosus: p = 0.002, d = 0.47). Examiners performed similar shear modulus measurements in the biceps femoris long head (p = 0.299; η2p = 0.041) and semitendinosus (p = 0.177; η2p = 0.066), although the experienced examiner showed a higher measurement repeatability (biceps femoris long head: ICC = 0.86-0.95, semitendinosus: ICC = 0.89-0.96; vs. biceps femoris long head: ICC = 0.78-0.87, semitendinosus: ICC = 0.66-0.87).

CONCLUSION

Transducer pressure influences the active shear modulus measurement between mild and moderate or hard pressures. Additionally, examiner experience seems to have no influence on muscle active shear modulus measurement when assessed at the same site (using casts).

IMPLICATIONS FOR PRACTICE

Future studies assessing active muscle shear modulus should use mild transducer pressure and having experienced examiners in order to improve measurement reliability.

Functional improvements associated with cranioplasty after stroke and traumatic brain injury: a cohort study

OBJECTIVE

Decompressive craniectomy is part of the acute management of several neurosurgical illnesses, and is commonly followed by cranioplasty. Data are still scarce on the functional and cognitive outcomes following cranioplasty. We aim to evaluate these outcomes in patients who underwent cranioplasty following traumatic brain injury (TBI) or stroke.

METHODS

In this prospective cohort, we assessed 1-month and 6-month neuropsychological and functional outcomes in TBI and stroke patients who underwent cranioplasty at a Brazilian tertiary center. The primary outcome was the change in the Digits Test at 1 and 6 months after cranioplasty. Repeated measures general linear models were employed to assess the patients' evolution and interactions with baseline characteristics. Effect size was estimated by the partial η2.

RESULTS

A total of 20 TBI and 14 stroke patients were included (mean age 42 ± 14 years; 52.9% male; average schooling 9.5 ± 3.8 years; 91.2% right-handed). We found significant improvements in the Digits Tests up to 6 months after cranioplasty (p = 0.004, partial η2 = 0.183), as well as in attention, episodic memory, verbal fluency, working memory, inhibitory control, visuoconstructive and visuospatial abilities (partial η2 0.106-0.305). We found no interaction between the cranioplasty effect and age, sex or schooling. Patients submitted to cranioplasty earlier (<1 year) after injury had better outcomes.

CONCLUSION

Cognitive and functional outcomes improved after cranioplasty following decompressive craniectomy for stroke or TBI. This effect was consistent regardless of age, sex, or education level and persisted after 6 months. Some degree of spontaneous improvement might have contributed to the results.

Discovery of indolizine lactones as anticancer agents and their optimization through late-stage functionalization

Indolizines fused with a seven-member lactone ring were identified as a promising scaffold in the search for new anticancer agents. Through a modular synthetic sequence, a library of cis and trans indolizines lactones had their antiproliferative activity evaluated against hormone-refractory prostate DU-145 and triple-negative breast MDA-MB-231 cancer cell lines. A methoxylated analogue was identified as an initial hit against MDA-MB-231 and late-stage functionalization of the indolizine core led to analogues within potencies up to twenty times higher than the parent precursor.

One-pot organocatalyzed synthesis of tricyclic indolizines

Indolizines and their saturated derivatives are important structural motifs present in several biologically active compounds of both natural and synthetic origin. We describe herein a one-pot approach for the synthesis of tricyclic indolizines catalyzed by a bicyclic imidazole-alcohol. The protocol is based on an aqueous Morita-Baylis-Hillman reaction between pyridine-2-carboxaldehydes and six- or seven-membered cyclic enones, followed by sequential intramolecular cyclization and dehydration. So, in a single operational step two new bonds (C-C and C-N) are formed in an organocatalyzed process that takes place in simple conditions (stirring in water at 60 °C for 12 h) and with great atom economy (water as the sole byproduct), affording the purified compounds in yields ranging from 19 to 70%. The facility of the cyclization strongly depends on the size of the cycloalkenone ring: while MBH adducts derived from six-, seven- or eight-membered cycloenones are readily transformed into the corresponding indolizines, cyclopentenone-derived MBH adducts do not cyclize. A competition experiment revealed that cycloheptenone-derived MBH adducts cyclize faster than cyclohexenone-derived adducts. Model DFT calculations have been performed to rationalize these reactivity trends.

Introduction of the method of intravaginal culture (IVC), through the device INVOCell routine laboratory RHA in Brazil

INTRODUCTION

The conventional in vitro fertilization and the intracytoplasmic sperm microinjection are currently the established techniques for the treatment of infertility. In the last decade, however, the process of in vitro fertilization has suffered several changes in ovulation induction and oocyte retrieval (Ranoux 1990, ; ).The INVO procedure has been used to treat patients with different causes of infertility in many countries. This is a procedure which was developed over 20 years ago and is simpler and less costly to the infertility treatment when compared to conventional techniques. Interesting finding of this intravaginal culture technique are the physiological benefits and the reduction of the number of handling steps, reducing the risk of contamination.

OBJECTIVE

This study aimed to evaluate the possibility of including the method INVO through the use of the deviceINVOCell™ in routine laboratory treatments of couple infertility. That, in turn, tends to provide the simplification of laboratory work and thereby reduce the costs of infertility treatment.

MATERIAL AND METHODS

40 women were included in this study, who were treated at the Service of Human Reproduction School Hospital Álvaro Alvim, in the period from August 2011 to January 2012. On all of them it was used the protocol of modified mild ovarian stimulation. The number of pre-embryos transferred into the uterine cavity followed the CFM Resolution nº. 1.957/10.

RESULTS AND CONCLUSION

There was no significant difference in the results presented by the device INVOCell™. Therefore showing that it can be included in routine laboratory assisted human reproduction.

Cardiovascular disease in an intensive care unit: patterns of an often fatal omen

Background

Care for the critically ill patient with Cardiovascular Disease (CVD) requires a unique management approach, as the theoretical critical threshold for decompensation is lower and inherent adaptive mechanisms may be compromised. We aimed to characterize the prognostic impact of CVD in patients admitted to an Intensive Care Unit (ICU).

Methods

We performed a cohort study of consecutive patients admitted to an ICU from January to December 2019. Patients were stratified as follows: (1) established CVD – presence of either atrial fibrillation, heart failure, coronary artery disease and/or peripheral artery disease; (2) at higher risk of CVD – known arterial hypertension, dyslipidemia, diabetes mellitus and/or current smoking, in the absence of established CVD; and (3) at lower risk of CVD – i.e. none of the above. The co-primary endpoints were all-cause death in ICU and death during index hospitalization.

Results

During 2019, there were 334 admissions in ICU, comprising a total of 296 patients (mean age 67±15 years, 58.1% male). Overall, 69 (23.3%) and 108 (36.5%) died in ICU and during index hospitalization, respectively. Compared to patients at lower risk of CVD, those at higher CVD risk or with established CVD had markers of more severe disease, as noted by higher risk scores (e.g., SAPS-II 35.0±20.0 vs. 43.5±22.3 vs. 52.6±20.0; p&lt;0.001), higher rates of mechanical ventilation (41.5 vs. 57.3 vs. 63.9%; p=0.020), shock during ICU stay (34.0 vs. 52.7 vs. 66.9%; p&lt;0.001) and acute kidney injury (26.4 vs. 35.5 vs. 57.9%; p&lt;0.001), respectively, as well as higher death rates in ICU (5.7 vs. 21.8 vs. 31.6%; p=0.001) and index hospitalization (9.4 vs. 37.3 vs. 46.6%; p&lt;0.001). In multivariate analysis, adjusted for age and cause of admission, established CVD independently predicted the risk of all-cause death in ICU (HR: 2.084; 95% CI: 1.136–3.823; p=0.018) and during index hospitalization (HR 1.712; CI: 1.009–2.889; p=0.046). The analysis for the group of patients at higher risk of CVD yielded similar results to the abovementioned.

Conclusion

Roughly 4 in every 5 patients admitted in ICU were at risk of or had established CVD. The presence of either of the above independently predicted a two- to three-fold higher risk of death during hospitalization. Our findings emphasize the considerable burden of CVD in ICU and underscore the importance of comprehensive management of the complex critically ill patient.

Funding Acknowledgement

Type of funding sources: None.

Chronic heart failure in intensive care unit: can we accurately predict the risk?

Background

Severity of disease scoring systems, namely the Simplified Acute Physiology Score (SAPS) and Acute Physiology and Chronic Health Evaluation (APACHE), are widely used to predict mortality in Intensive Care Units (ICU). Yet, neither score includes chronic HF in their model. We aimed to evaluate whether these scores perform well in risk prediction of death of patients previously diagnosed with heart failure (HF).

Methodology

This is a single-center retrospective cohort of patients admitted to an ICU in 2019. Those whose admission lasted &lt;24 hours were excluded from analysis. The SAPS II and APACHE II scores were calculated using data from the first 24 hours of ICU admission, imputing the worst variable obtained within this timeframe. HF was defined according to the ESC recommendations. In order to assess the performance of the scores, Receiver Operating Characteristic (ROC) Curves were used to predict the risk of death in ICU in HF compared to the non-HF population.

Results

A total of 267 patients were hospitalized in ICU for a period over 24 hours in 2019 (mean age 67±16 years; 58.8% males; 21.7% with chronic HF; 33.7% admitted for sepsis). Compared to patients without HF, those with chronic HF were older (74±13 vs. 65±16 years; p&lt;0.001) and had higher risk scores (mean SAPS II: 43.2±21.7 vs. 56.5±20.7; p&lt;0.001; mean APACHE II: 19.8±10.0 vs. 25.1±10.0; p&lt;0.001). Moreover, these patients were at higher risk of meaningful events during hospitalization (e.g. acute kidney injury: 38.0 vs. 66.1%; p&lt;0.001; shock at any time: 52.4 vs. 67.8%; p=0.036). Furthermore, patients with HF had a trend towards higher mortality rates in ICU (17.3 vs. 28.8%; p=0.051) and a significantly higher death in overall hospitalization (30.8 vs. 45.8%; p=0.032). ROC curves performed well in predicting the risk of ICU death regardless of HF (SAPS II – AUC 0.78 vs. 0.81; p=0.36; APACHE II – AUC 0.75 vs. 0.78; p=0.37).

Conclusion

Approximately 1 in every 4 patients admitted to the ICU had chronic HF. Traditional risk scoring systems (SAPS II and APACHE II) performed well regardless of HF. While these results are reassuring as far as risk stratification accuracy is concerned, HF patients remained at a higher risk for worse outcomes. Therefore, prognostic tools with a therapeutic clinical applicability are urgently needed to improve the outcome of this population.

Funding Acknowledgement

Type of funding sources: None.

Synthetic Spirocyclohexadienones as New Anti-Migratory Compounds in Triple- Negative Breast Cancer Cell Migration

BACKGROUND

Triple-negative BC is the most aggressive type of breast cancer and its lack of responsiveness to conventional therapies requires screening of new chemical entities. Anti-migratory compounds are promising to treat metastatic cancer since they inhibit one of the main steps of the metastatic cascade. Spirocyclic compounds are non-conventional structures used as building blocks for the synthesis of biologically active molecules and considered interesting structures in the search for new targets in cancer research.

OBJECTIVE

Here, we evaluated the potential of eight synthetic spirocyclohexadienones as cell migration inhibitors.

METHODS

The anti-migratory ability of compounds was tested by wound healing and Boyden chamber approaches. Experiments in tubulin were performed by fluorescence and tubulin polymerization techniques. Finally, compounds were submitted to cell proliferation inhibition and flow cytometry assays to explore the mechanism by which they inhibit cell migration.

RESULTS

Four compounds inhibited cell migration significantly. Analogs containing the 3,4,5-trimethoxyphenil ring at R¹ position were the most potent and, thus, selected for additional experiments. Tubulin polymerization and fluorescence assays highlighted a possible binding of spirocyclohexadienones in the colchicine binding site; however, these compounds did not affect the cell cycle to the same extent as colchicine. Cell proliferation was affected and, notably, the most potent analogs induced apoptosis of tumor cells, suggesting a different mechanism by which they inhibit cell migration.

CONCLUSION

We presented, for the first time, a series of eight synthetic spirocyclohexadienones with the ability to inhibit TNBC cell migration. These compounds represent a new category to be explored as anticancer agents.

Methodologies for the synthesis of quaternary carbon centers via hydroalkylation of unactivated olefins: twenty years of advances

Olefin double-bond functionalization has been established as an excellent strategy for the construction of elaborate molecules. In particular, the hydroalkylation of olefins represents a straightforward strategy for the synthesis of new C(sp³)–C(sp³) bonds, with concomitant formation of challenging quaternary carbon centers. In the last 20 years, numerous hydroalkylation methodologies have emerged that have explored the diverse reactivity patterns of the olefin double bond. This review presents examples of olefins acting as electrophilic partners when coordinated with electrophilic transition-metal complexes or, in more recent approaches, when used as precursors of nucleophilic radical species in metal hydride hydrogen atom transfer reactions. This unique reactivity, combined with the wide availability of olefins as starting materials and the success reported in the construction of all-carbon C(sp³) quaternary centers, makes hydroalkylation reactions an ideal platform for the synthesis of molecules with increased molecular complexity.

Anthelmintic activity of a nanoformulation based on thiophenes identified in Tagetes patula L. (Asteraceae) against the small ruminant nematode Haemonchus contortus

The synthesis of thiophenic compounds, previously identified in Tagetes patula, revealed that 4-(5'-(hydroxymethyl)-[2,2'-bithiophene]-5-yl)but-3-yn-1-ol), or simply Thio1, has a pronounced in vitro anthelmintic effect against Haemonchus contortus, showing 100% efficacy in the egg hatch and larval development tests presenting EC₅₀ = 0.1731 mg.mL^-1 and EC₅₀ = 0.3243 mg.mL^-1, respectively. So, this compound was selected to preparation of a nanostructured formulation to be orally administered to Santa Inês sheep. In general, from the fecal egg count reduction test (FECRT), it was observed that the product kept the parasitic load in the digestive tract of the hosts stable, with eggs per gram of faeces (EPG) counts having a mean value < 3,000 (EPG_mean = 2167.1, efficacy = 36,45%), thus protecting the animals from health risks caused by a massive nematode infestation. To better understand the mode of action of this thiophene derivative, in silico molecular modeling studies were carried out with the glutamate-activated chloride channel (GluCl), a well-known molecular target of anthelmintic compounds. Based on the affinity score (GlideScore = -5.7 kcal.mol^-1) and the proposed binding mode, Thio1 could be classified as a potential GluCl ligand, justifying the promising results observed in the anthelmintic assays.

Through space JFH spin-spin coupling constant transmission pathways in 2-(trifluoromethyl)thiophenol: formation of unusual stabilizing bifurcated CFHS and CFSH interactions

Given its importance and the possibility of organic F to participate in hydrogen bonds (H-bonds), the understanding of its behavior as a H-bond acceptor with different donors is crucial. The interest in organofluorine compounds and the works related to the study of the participation of this atom in non-covalent interactions is constantly growing. Following recent studies in this subject, we evaluated the existence of two bifurcated intramolecular interactions, a bifurcated CFHS H-bond in the cis conformer of 2-trifluoromethylthiophenol and an unusual, bifurcated CFSH interaction in the trans conformer. The JFH spin-spin coupling constant (SSCC) was evaluated for 2-trifluoromethylthiophenol both experimentally by 1H and 19F NMR and theoretically using the natural bond orbitals (NBO), the quantum theory of atoms in molecules (QTAIM) and the non-covalent interactions (NCI) framework. Although both interactions are crucial for the stabilization of the conformer geometries, the observed positive JFH spin-spin coupling constant (SSCC) is mainly resultant from the trans conformer, which has a large calculated positive SSCC, and is transmitted through steric interactions involving the F lone pairs and the σSH bonding orbital.

Disseminated Saprochaete capitata fungal infection in a patient with acute myeloid leukemia

The case highlights the importance of actively obtaining informative samples at an early stage and of prompt initiation of combination therapy with antifungal drugs.

Why does transcultural consultation matter?

Introduction

Psychiatrists should be aware of the new challenges and needs that globalization poses.

Objectives

To highlight the need for a culturally sensitive approach to mental health.

Methods

Non-systematic review of “cultural consultation” on PubMed.

Results

Most people assume a direct connection between pathophysiology and clinical symptoms. However, evidence shows that the translation of pathophysiology and psychopathology into specific symptoms is mediated by cognitive processes and social interactions, which reflect models/practices specific to our culture. Patients focus on specific aspects of being sick, reinforced by cultural narratives or to fit expectations. Thus, people from different cultural backgrounds might have trouble communicating; cultural idioms of distress can be misinterpreted. The role of structural violence bestowed upon cultural minorities, which leads to discrimination and social exclusion, has extensively been studied as a risk factor for mental illness. Furthermore, ignoring cultural differences and diversity has been shown to contribute to healthcare disparities, hampering access to care and diminishing the quality of care received. In Canada, the Cultural Consultation Model provides cultural expertise, either by evaluating patients (preferably accompanied by the referring doctor, a translator and cultural mediator) for 1-3 sessions, providing recommendations to the referring doctor; or providing consulting to a referring doctor or organisation, through general guidance or discussion of specific cases.

Conclusions

In an evergrowing globalization process, we will inevitably have more contact with patients from culturally distinct backgrounds. To provide the best care, we must be aware of the ways in which culture can shape symptom expression, and take into account cultural explanations and preferences.

Disclosure

No significant relationships.

Systematic review of racial and ethnic disparities pertaining treatment in mental healthcare amongst incarcerated patients

Introduction

Research has shown that ethnic/racial minorities have a higher risk of homelessness, involvement with the criminal system, psychiatric misdiagnosis, treatment delay, and being prescribed first (versus second) generation antipsychotics.

Objectives

To investigate if the disparities found in the community are replicated in incarcerated patients.

Methods

Systematic review on PubMed for articles that fulfilled criteria for 4 domains: prison, psychosis, race/ethnic, and treatment.

Results

Forty-one articles matched the search criteria. Of those, 24 were irrelevant; 2 were inaccessible. Fifteen articles were considered; most highlighted the interplay between the criminal system, homelessness, mental disorders, and ethnic/racial minorities. Five articles highlighted differences in treatment. One stated that African-Americans and Asians were less likely than Whites to have access to mental health services. Concerning treatment for substance use disorders, one study found Hispanic inmates were more often engaged in treatment, followed by Caucasians and lastly, African-Americans; a different study reported the percentage of Whites and Blacks receiving treatment was similar, while Latinos were under-represented. Whites were most likely to have mental health counseling/substance use treatment as part of their sentence. A study from New-Zealand stated that treatment for mental disorders was less common for Maoris, in whom suicidal thoughts were often unrecognized. The last study reported a higher risk of self-harm for foreign patients, coupled with non-recognition/misinterpretation of symptoms.

Conclusions

Racial/ethnic inequalities show that disparities in healthcare are pervasive in all settings. More studies are needed to better understand the complex nature of this problem.

Disclosure

No significant relationships.

Synthetic cyclopenta[b]indoles exhibit antineoplastic activity by targeting microtubule dynamics in acute myeloid leukemia cells

Acute promyelocytic leukemia (APL) is associated with PML-RARα oncogene, which is treated using all-trans retinoic acid (ATRA)-based chemotherapy. However, chemoresistance is observed in 20-30% of treated patients and represents a clinical challenge, raising the importance of the development of new therapeutic options. In the present study, the effects of three synthetic cyclopenta[b]indoles on the leukemia phenotype were investigated using NB4 (ATRA-sensitive) and NB4-R2 (ATRA-resistant) cells. Among the tested synthetic cyclopenta[b]indoles, compound 2, which contains a heterocyclic nucleus, was the most active, presenting time-dependent cytotoxic activity in the μM range in APL cells, without cytotoxicity for normal leukocytes, and was selected for further characterization. Compound 2 significantly decreased clonogenicity, increased apoptosis, and caused cell cycle arrest at S and G₂/M phases in a drug concentration-dependent manner. Morphological analyses indicated aberrant mitosis and diffuse tubulin staining upon compound 2 exposure, which corroborates cell cycle findings. In the molecular scenario, compound 2 reduced STMN1 expression and activity, and induced PARP1 cleavage and H2AX and CHK2 phosphorylation, and modulated CDKN1A, PMAIP1, GADD45A, and XRCC3 expressions, indicating reduction of cell proliferation, apoptosis, and DNA damage. Moreover, in the in vivo tubulin polymerization assay, NB4 and NB4-R2 cells showed a reduction in the levels of polymerized tubulin upon compound 2 exposure, which indicates tubulin as a target of the drug. Molecular docking supports this hypothesis. Taken together, these data indicated that compound 2 exhibits antileukemic effects through disrupting the microtubule dynamics, identifying a possible novel potential antineoplastic agent for the treatment of ATRA-resistant APL.

Acute organ failure and risk of admission to intensive medical care in cancer patients: a single center prospective cohort study

OBJECTIVE

To ascertain the cumulative incidence of acute organ failure and intensive care unit admission in cancer patients.

METHODS

This was a single-center prospective cohort study of adult cancer patients admitted for unscheduled inpatient care while on systemic cancer treatment.

RESULTS

Between August 2018 and February 2019, 10,392 patients were on systemic treatment, 358 had unscheduled inpatient care and were eligible for inclusion, and 285 were included. The mean age was 60.9 years, 50.9% were male, and 17.9% of patients had hematologic cancers. The cumulative risk of acute organ failure was 39.6% (95%CI: 35 - 44), and that of intensive care unit admission among patients with acute organ failure was 15.0% (95%CI: 12 - 18). On admission, 62.1% of patients were considered not eligible for artificial organ replacement therapy. The median follow-up time was 9.5 months. Inpatient mortality was 17.5%, with an intensive care unit mortality rate of 58.8% and a median cohort survival of 134 days (95%CI: 106 - 162). In multivariate analysis, acute organ failure was associated with 6-month postdischarge mortality (HR 1.6; 95%CI: 1.2 - 2.2).

CONCLUSION

The risk of acute organ failure in cancer patients admitted for unscheduled inpatient care while on systemic treatment was 39.6%, and the risk of intensive care unit admission was 15.0%. Acute organ failure in cancer patients was an independent poor prognostic factor for inpatient hospital mortality and 6-month survival.

Brønsted-acid-catalyzed selective Friedel-Crafts monoalkylation of isatins with indolizines in water

The controlled mono-addition of indolizines to isatins under very mild conditions is described. The reaction occurs in water using diphenylphosphate as the catalyst, which is dramatically accelerated by surfactant addition. 3-Hydroxy-3-indolizinyl-2-oxindole scaffolds were synthesized in up to >99% yield. Notably, in organic solvents only bis-addition products were observed.

Origin of the Diastereoselectivity of the Heterogeneous Hydrogenation of a Substituted Indolizine

In this work, the stereoselective heterogeneous hydrogenation of a tetrasubstituted indolizine was studied. Partial hydrogenation products were obtained in three steps from a substituted pyridine-2-carboxaldehyde prepared from commercial pyridoxine hydrochloride. The hydrogenation of the indolizine ring was shown to be diastereoselective, forming trans-6b and cis-9. Theoretical calculations (ab initio and DFT) were used to rationalize the unusual trans stereoselectivity for 6b, and a keto–enol tautomerism under kinetic control has been proposed as the source of diastereoselectivity.

Discovery of highly potent and selective antiparasitic new oxadiazole and hydroxy-oxindole small molecule hybrids

A series of highly active hybrids were discovered as novel antiparasitic agents. Two heterocyclic scaffolds (1,2,4-oxadiazole and 3-hydroxy-2-oxindole) were linked, and the resulting compounds showed in vitro activities against intracellular amastigotes of two protozoan parasites, Trypanosoma cruzi and Leishmania infantum. Their cytotoxicity was assessed using HFF-1 fibroblasts and HepG2 hepatocytes. Compounds 5b, 5d, 8h and 8o showed selectivity against L. infantum (IC₅₀ values of 3.89, 2.38, 2.50 and 2.85 μM, respectively). Compounds 4c, 4q, 8a and 8k were the most potent against T. cruzi, exhibiting IC₅₀ values of 6.20, 2.20, 2.30 and 2.20 μM, respectively. Additionally, the most potent anti-T. cruzi compounds showed in vitro efficacies comparable or superior to that of benznidazole. These easy-to-synthesize molecules represent novel chemotypes for the design of potent and selective lead compounds for Chagas disease and leishmaniasis drug discovery.

Catalyst-Free Conjugate Addition of Indolizines to In Situ-Generated Oxidized Morita-Baylis-Hillman Adducts

Sequential one-pot 2-iodoxybenzoic acid (IBX) oxidation of Morita-Baylis-Hillman (MBH) adducts followed by catalyst-free indolizine conjugate addition was developed. The wide scopes of MBH adducts and indolizines were investigated, and densely functionalized adducts were obtained in yields of up to 94%. The conjugate addition step occurred in less than a minute at room temperature with total regioselectivity toward indolizine C3 carbon. Less nucleophilic C1 carbon was also alkylated when C3-substituted indolizines were employed as the substrate.

Synthesis of 1,4,6-Tricarbonyl Compounds via Regioselective Gold(I)-Catalyzed Alkyne Hydration and Their Application in the Synthesis of α-Arylidene-butyrolactones

We report a direct, straightforward, and regioselective hydration of 1,4-enynes designed from Morita-Baylis-Hillman adducts. Under smooth conditions and short reaction times, gold-catalyzed hydration of internal alkynes provides synthetically useful ketones as single regioisomers in yields higher than 90%. The synthetic usefulness of this protocol was demonstrated by the conversion of selected ketones into biologically valuable α-alkylidene-γ-lactones upon reduction with sodium borohydride. In the course of the scope evaluation, we discovered that this methodology could also furnish α-arylidene-β,γ-butenolides.

Aza-Morita–Baylis–Hillman Reaction with Vinyl-oxadiazoles: An Expeditious Approach to Access New Heterocyclic Arrangements

In this communication, we disclosed a new aza-MBH reaction in which traditional nucleophilic partners of these reactions (e.g., acrylates, nitroolefins or enones) were replaced by vinyl-1,2,4-oxadiazoles. Thus, the aza-MBH reaction between 5-aryl-3-vinyl-1,2,4-oxadiazoles and N-sulfonylimines, catalyzed by the mixture DABCO/AcOH, provides a class of new adduct in yields varying from 31% up to 93% in reaction times from 30 minutes to 24 hours. Due to the biological activities and technological applications associated with the 1,2,4-oxadiazole motifs, this new class of heterocycles offers great synthetic and commercial potentiality.

Intramolecular H-Bond Is Formed in 2-Fluorophenol and 2-Fluorothiophenol, but It May Not Be the Main Pathway of the JFH Coupling Constant Transmission

The intramolecular CF···HX (X = O or S) H-bond and J_FH spin-spin coupling constants (SSCCs) in 2-fluorophenol and 2-fluorothiophenol were investigated experimentally by ¹H and ¹⁹F NMR and theoretically in the framework of the natural bond orbital analysis. In contrast with recent findings from the literature, the results obtained in this work showed that an intramolecular H-bond is formed in the cis conformers and that it has an electrostatic origin. Such an intramolecular electrostatic H-bond is the interaction that rules the conformational preferences on these compounds. Moreover, the natural J-coupling analysis indicated that the J_HF SSCC in 2-fluorophenol has its origin on LP(F)/σ_OH steric interactions and should be labeled as ^4TSJ_HF. On the other hand, the analogue SSCC for 2-fluorothiophenol has its origin on the intramolecular H-bond LP(F) → σ_SH^* hyperconjugative interaction and should be described as a ^1hJ_FH SSCC.

Spirocyclohexadienones as an Uncommon Scaffold for Acetylcholinesterase Inhibitory Activity

BACKGROUND

The most important cause of dementia affecting elderly people is the Alzheimer's disease (AD). Patients affected by this progressive and neurodegenerative disease have severe memory and cognitive function impairments. Some medicines used for treating this disease in the early stages are based on inhibition of acetylcholinesterase. Population aging should contribute to increase the cases of patients suffering from Alzheimer's disease, thus requiring the development of new therapeutic entities for the treatment of this disease.

METHODS

The objective of this work is to identify new substances that have spatial structural similarity with donepezil, an efficient commercial drug used for the treatment of Alzheimer's disease, and to evaluate the capacity of inhibition of these new substances against the enzyme acetylcholinesterase.

RESULTS

Based on a previous results of our group, we prepared a set of 11 spirocyclohexadienones with different substitutions patterns in three steps and overall yield of up to 59%. These compounds were evaluated in vitro against acetylcholinesterase. We found that eight of them are able to inhibit the acetylcholinesterase activity, with IC50 values ranging from 0.12 to 12.67 µM. Molecular docking study indicated that the spirocyclohexadienone, 9e (IC50 = 0.12 µM), a mixedtype AChE inhibitor, showed a good interaction at active site of the enzyme, including the cationic (CAS) and the peripheral site (PAS).

CONCLUSION

We described the first study aimed at investigating the biological properties of spirocyclohexadienones as acetylcholinesterase inhibitors. Thus, we have identified an inhibitor, which provided valuable insights for further studies aimed at the discovery of more potent acetylcholinesterase inhibitors.

Vinyl-1,2,4-oxadiazoles Behave as Nucleophilic Partners in Morita-Baylis-Hillman Reactions

We describe that vinyl-oxadiazoles function as a new and efficient nucleophilic partner for the Morita-Baylis-Hillman (MBH) reaction. The reaction between 5-vinyl-3-aryl-1,2,4-oxadiazoles and aromatic and aliphatic aldehydes, catalyzed by DABCO in the absence of solvent, showed high efficiency to afford a new class of heterocyclic MBH adducts with potential biological activity on yields up to 99% and short reaction times. These synthetically attractive adducts bear a heterocyclic scaffold of large pharmaceutical and commercial interest associated with a plethora of biological effects and technological applications. We also demonstrate their synthetic usefulness by a photoinduced addition reaction to a polyfunctionalized amino alcohol.

Short and Diastereoselective Total Synthesis of the Polyhydroxylated Pyrrolidine LAB-1: A Potent α-Glycosidase Inhibitor

We described herein a total synthesis of 1,4-dideoxy-1,4-imino-l-arabinitol [(2S,3S,4S)-2-(hydroxymethyl)pyrrolidine-3,4-diol, LAB-1], a polyhydroxylated pyrrolidine, which has been demonstrated to be a selective and potent α-glycosidase inhibitor. The main features of our approach are its shortness, efficiency, and simplicity. The total synthesis was accomplished in 6 steps with an overall yield of 12%, starting from a chiral optically active Morita–Baylis–Hillman (MBH) adduct prepared (without epimerization), from Garner’s aldehyde. As far as we know, this is the first report describing the total synthesis of this biologically active pyrrolidine by exploring the synthetic versatility of a MBH adduct.

Catalytic Asymmetric Conjugate Addition of Indolizines to α,β-Unsaturated Ketones

A catalytic enantioselective conjugate addition of indolizines to enones is described. The chiral phosphoric acid (S)-TRIP activates α,β-unsaturated ketones, thereby promoting an enantioface-differentiating attack by indolizines. Using this reaction, several alkylated indolizines were synthesized in good yields and with enantiomeric ratios of up to 98:2.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Withdrawing and Withholding Life Support in Patients With Cancer in an ICU Setting: A 5-Year Experience at a European Cancer Center

OBJECTIVE

This was an observational retrospective study aimed to examine the frequency and associated factors of withdrawing or withholding life support (WWLS) in the intensive care unit (ICU) of a comprehensive cancer center.

METHODS

Medical records of adult patients with cancer admitted to the ICU between January 2010 and December 2014 were reviewed. Patients who died during that period were classified into 2 groups: full life support and withdrawing and withholding life support. The relative impact of demographic and clinical factors was assessed using logistic regression.

RESULTS

A total of 247 patients died in our unit (mortality rate of 16.3%). Their median age was 62 (interquartile range [IQR] 51-73) years, there were 142 (57.5%) male patients, and they had predominantly solid malignancies (62.3%). The median Simplified Acute Physiology Score II and Acute Physiology and Chronic Health Evaluation scores were 67 (IQR 54-80) and 29 (IQR 23-55), respectively. Ninety-six (38.9%) patients died after WWLS with no statistically significant differences in decisions to limit therapy during the study period. Patients with advanced age, solid malignancies, nonneutropenic, and longer duration of mechanical ventilation were more likely to die after WWLS. In multivariate analysis, presenting with neutropenia was independently associated with a lower likelihood of dying after WWLS (odds ratio: 0.34, 95% confidence interval: 0.15-0.80).

CONCLUSION

Limitation of therapy has been a common practice in oncologic ICUs over recent years. Neutropenia is an independent predictor of limitation of therapy.