Cell-Engineered Recombinant α-Synuclein: A Gage R&R Validated Protocol.

α-Synuclein (α-Syn) misfolding and its presence in Lewy bodies are observed in almost all Parkinson's disease (PD) patients. Basic biomedical research would benefit from a quick, low-cost approach to purifying α-Syn and developing in vitro and in vivo models for PD. Several research groups utilize PFF-based models, yet the production of α-Syn PFFs is inconsistent, resulting in nonconclusive findings. Some research laboratories prepare recombinant α-Syn (r α-Syn) by molecular cloning to overexpress α-Syn with various purifying techniques. Laboratory-to-laboratory protocols cause considerable variability and sometimes contradictory findings. PD researchers spend more on protein than solving α-Syn's riddles. This article uncovered a novel method for expressing and purifying r α-Syn validated through gage reproducibility and repeatability (Gage R&R). For the production of r α-Syn, we have employed the ability of a high-cell-density-based expression system to overexpress protein in BL21(DE3). A simple, high-throughput, nonchromatographical purification protocol has been devised to facilitate research with higher reproducibility, which was validated through Gage R&R. A crossover experimental design was utilized, and the purified protein was characterized using orthogonal high-end analytical methods, which displayed higher similarity between the isolated r α-Syn. Batch-to-batch variability was the least for produced protein and hence can be utilized for exploring the iceberg of PD.

Medicinal chemical optimization of fluorescent pyrrole-based COX-2 probes.

Recent studies have demonstrated the ability of human prostaglandin-endoperoxide synthase 2 (COX-2) to guide the formation of fluorescent pyrroles through the Paal-Knorr reaction resulting in the discovery of a central motif. This initial discovery prompted further exploration of this motif for the design of COX-2 inhibitors through the modifications of the substituents on the pyrrole core. This effort led to the discovery of a set of pyrroles whose activity was comparable to Celecoxib, an orally prescribed nonsteroidal anti-inflammatory COX-2 inhibitor. Furthermore, structure-activity relationship (SAR) data, important for the discovery of COX-2 inhibitors, has been obtained.

Lessons in Organic Fluorescent Probe Discovery.

Fluorescent probes have gained profound use in biotechnology, drug discovery, medical diagnostics, molecular and cell biology. The development of methods for the translation of fluorophores into fluorescent probes continues to be a robust field for medicinal chemists and chemical biologists, alike. Access to new experimental designs has enabled molecular diversification and led to the identification of new approaches to probe discovery. This review provides a synopsis of the recent lessons in modern fluorescent probe discovery.

Impact of the pandemic on cancer care: Lessons learnt from a rural cancer center in the first 3 months.

INTRODUCTION: The COVID-19 outbreak and the subsequent declaration of pandemic was an unprecedented event, which created different complex situations for treatment of cancer patients. A critical assessment of the response to this calamity and its impact on healthcare workers (HCWs) and patient care in a dedicated cancer hospital is analyzed. SITE OF STUDY: Indrayani Cancer Hospital, Alandi, Pune, India. MATERIALS AND METHODS: Due to the pandemic, standard operating protocols were decided on for each department. Analysis of the impact on healthcare was done by comparing the number of patients taking treatment in the lockdown period in India with the previous year's data in the same corresponding period in all three departments. The impact of COVID infection on the HCW and its repercussions were analyzed. RESULTS: There was a marked decrease in the total number of patients during the lockdown period. The most affected department was surgical oncology. None of our patients contracted COVID-19, but one HCW was found to be positive. CONCLUSION: Strict adherence to protocols along with the support of the government authorities can prevent the spread of this virus thus providing optimal patient outcomes. The treatment of patients with cancer should not be delayed, even in times of a pandemic.

Catalytic Transformations of Alkynes into either α-Alkoxy or α-Aryl Enolates: Mannich Reactions by Cooperative Catalysis and Evidence for Nucleophile-Directed Chemoselectivity.

The catalytic formation of gold enolates from alkynes, nitrones, and nucleophiles is described, and their Mannich reactions result in nucleophile-directed chemoselectivity through cooperative catalysis. For 1-alkyn-4-ols and 2-ethynylphenols, their gold-catalyzed nitrone oxidations afforded N-containing dihydrofuran-3(2H)-ones with syn selectivity. The mechanism involves the Mannich reactions of gold enolates with imines through an O-H-N hydrogen-bonding motif. For aryloxyethynes, their gold enolates react selectively with nitrones to deliver 3-alkylidenebenzofuran-2-ones, as controlled by a C-H-O hydrogen-bonding motif.

Prospective evaluation of maternal morbidity and mortality in post-cesarean section patients admitted to postanesthesia intensive care unit.

BACKGROUND AND AIMS: Critical illness may complicate any pregnancy. Timely intensive care management of critically ill obstetric patients has better outcomes than expected from the initial severity of illness. The aim was to study the indications of transfer of post-cesarean section patients to post-anesthesia intensive care unit (PACU). (PACU transfer indicated that the patient required intensive care). MATERIALS AND METHODS: This was a prospective observational study carried out in the PACU of a tertiary care teaching public hospital over a period of 2 years. Sixty-one postoperative lower segment cesarean section (LSCS) females admitted consecutively in PACU were studied. The study included obstetric PACU utilization rate, intensive care unit interventions, outcome of mother, Acute Physiology and Chronic Health Evaluation (APACHE II) score, and its correlation with mortality. RESULTS: Postanesthesia intensive care unit admission rate was 2.8% and obstetric PACU utilization rate was 3.22%. Of 61 patients, four had expired. Obstetric indications (67.2%) were the most common cause of admission to PACU. Among the obstetric indications hemorrhage (36.1%) was found to be a statistically significant indication for PACU admission followed by hypertensive disorder of pregnancy (29.5%). Cardiovascular disease (16.4%) was the most common nonobstetric indication for PACU transfer and was associated with high mortality. The observed mortality was 6.557%, which was lower than predicted mortality by APACHE II Score. CONCLUSION: Obstetric hemorrhage, hypertensive disorders of pregnancy and cardiovascular diseases are the leading causes of PACU admission in post LSCS patients. Prompt provision of intensive care to critically ill obstetric patients can lead to a significant drop in maternal morbidity and mortality.

Sphaeropsidin A C15-C16 Cross-Metathesis Analogues with Potent Anticancer Activity.

We recently discovered that sphaeropsidin A (SphA), a fungal metabolite from Diplodia cupressi, overcomes apoptosis resistance in cancer cells by inducing cellular shrinkage by impairing regulatory volume increase. Previously, we prepared a pyrene-conjugated derivative of SphA by a cross-metathesis reaction involving the phytotoxin's C15,C16-alkene. This derivative's evaluation in a cancer cell panel revealed a significant increase in potency, with the IC50 values 5-10× lower than those displayed by the original natural product. Herein, we describe the preparation and anticancer evaluation of fifteen novel C15,C16-alkene cross-metathesis analogues in which the pyrene moiety was replaced with other aromatic or non-aromatic hydrophobic groups. The idea for this replacement was to prepare a family of compounds that would not be predicted to be mutagenic compared with the original pyrene analogue. We predict several of our new compounds to be non-mutagenic, while retaining the high potency of the original pyrene-containing analogues. Examples of these potential lead compounds included those containing pentamethylphenyl and triphenylethylene pendant groups. As an additional feature of the current investigation, we prepared several deuterated pyrene-containing compounds to overcome intellectual property issues associated with non-patentability of the original pyrene derivative.

New hemisynthetic derivatives of sphaeropsidin phytotoxins triggering severe endoplasmic reticulum swelling in cancer cells.

Sphaeropsidins are iso-pimarane diterpenes produced by phytopathogenic fungi that display promising anticancer activities. Sphaeropsidin A, in particular, has been shown to counteract regulatory volume increase, a process used by cancer cells to avoid apoptosis. This study reports the hemi-synthesis of new lipophilic derivatives obtained by modifications of the C15,C16-alkene moiety. Several of these compounds triggered severe ER swelling associated with strong proteasomal inhibition and consequently cell death, a feature that was not observed with respect to mode of action of the natural product. Significantly, an analysis from the National Cancer Institute sixty cell line testing did not reveal any correlations between the most potent derivative and any other compound in the database, except at high concentrations (LC50). This study led to the discovery of a new set of sphaeropsidin derivatives that may be exploited as potential anti-cancer agents, notably due to their maintained activity towards multidrug resistant models.

Synthesis, biological evaluation and docking studies of silicon incorporated diarylpyrroles as MmpL3 inhibitors: An effective strategy towards development of potent anti-tubercular agents.

Growing global demand for new molecules to treat tuberculosis has created an urgent need to develop novel strategies to combat the menace. BM212 related compounds were found to be potent anti-TB agents and they inhibit mycolic acid transporter, MmpL3, a known potent drug target from Mycobacterium tuberculosis. In order to enhance their inhibitory potency, several silicon analogues of diarylpyrroles related to BM212 were designed, synthesized, and evaluated for anti-tubercular activities. In Alamar blue assay, most of the silicon-incorporated compounds were found to be more potent than the parent compound (BM212), against Mycobacterium tuberculosis (MIC = 1.7 µM, H37Rv). Docking results from the crystal structure of MmpL3 and silicon analogues as pharmacophore model also strongly correlate with the biological assays and suggest that the incorporation of silicon in the inhibitor scaffold could enhance their potency by stabilizing the hydrophobic residues at the binding pocket. The best docking hit, compound 12 showed an MIC of 0.1 µM against H37Rv with an acceptable in vitro ADME profile and excellent selectivity index. Overall, the present study indicates that, the designed silicon analogues, especially compound 12 could be a good inhibitor for an intrinsically flexible drug-binding pocket of MmpL3 and has potential for further development as anti-tubercular agents.

A fluorescent target-guided Paal-Knorr reaction.

It has become increasingly apparent that high-diversity chemical reactions play a significant role in the discovery of bioactive small molecules. Here, we describe an expanse of this paradigm, combining a 'target-guided synthesis' concept with Paal-Knorr chemistry applied to the preparation of fluorescent ligands for human prostaglandin-endoperoxide synthase (COX-2).

Gold-Catalyzed Oxidative Hydrative Alkenylations of Propargyl Aryl Thioethers with Quinoline N-Oxides Involving a 1,3-Sulfur Migration.

This work reports gold-catalyzed oxidative alkenylations of quinoline N-oxides with propargyl aryl thioethers to afford 3-hydroxy-1-alkylidenephenylthiopropan-2-one via a 1,3-sulfur group migration. The mechanism of this reaction is postulated to involve an α-oxo gold carbene intermediate followed by formation of a four-membered sulfonium ring that is ring-opened by one H2O to form a gold enolate. A final condensation of this enolate with a second quinoline N-oxide delivers an alkenylation product accompanied by a 1,3-sulfur shift.

Gold-catalyzed reactions of propargylic esters with vinylazides for the synthesis of Z- or E-configured buta-1,3-dien-2-yl esters.

Gold-catalyzed synthesis of buta-1,3-dien-2-yl esters by the reaction of propargyl esters with vinylazides is described; the reaction mechanism is postulated to involve a vinyl attack of vinylazides at alkenyl gold carbenes.