Screening the pandemic response box identified benzimidazole carbamates, Olorofim and ravuconazole as promising drug candidates for the treatment of eumycetoma.

Eumycetoma is a chronic subcutaneous neglected tropical disease that can be caused by more than 40 different fungal causative agents. The most common causative agents produce black grains and belong to the fungal orders Sordariales and Pleosporales. The current antifungal agents used to treat eumycetoma are itraconazole or terbinafine, however, their cure rates are low. To find novel drugs for eumycetoma, we screened 400 diverse drug-like molecules from the Pandemic Response Box against common eumycetoma causative agents as part of the Open Source Mycetoma initiative (MycetOS). 26 compounds were able to inhibit the growth of Madurella mycetomatis, Madurella pseudomycetomatis and Madurella tropicana, 26 compounds inhibited Falciformispora senegalensis and seven inhibited growth of Medicopsis romeroi in vitro. Four compounds were able to inhibit the growth of all five species of fungi tested. They are the benzimidazole carbamates fenbendazole and carbendazim, the 8-aminoquinolone derivative tafenoquine and MMV1578570. Minimal inhibitory concentrations were then determined for the compounds active against M. mycetomatis. Compounds showing potent activity in vitro were further tested in vivo. Fenbendazole, MMV1782387, ravuconazole and olorofim were able to significantly prolong Galleria mellonella larvae survival and are promising candidates to explore in mycetoma treatment and to also serve as scaffolds for medicinal chemistry optimisation in the search for novel antifungals to treat eumycetoma.

The Inhibitory Effect of Plant Extracts on Growth of the Foodborne Pathogen, Listeria monocytogenes.

Listeria monocytogenes is a foodborne pathogen responsible for about 1600 illnesses each year in the United States (US) and about 2500 confirmed invasive human cases in European Union (EU) countries. Several technologies and antimicrobials are applied to control the presence of L. monocytogenes in food. Among these, the use of natural antimicrobials is preferred by consumers. This is due to their ability to inhibit the growth of foodborne pathogens but not prompt negative safety concerns. Among natural antimicrobials, plant extracts are used to inactivate L. monocytogenes. However, there is a large amount of these types of extracts, and their active compounds remain unexplored. The aim of this study was to evaluate the antibacterial activity against L. monocytogenes of about 800 plant extracts derived from plants native to different countries worldwide. The minimal inhibitory concentrations (MICs) were determined, and scanning electron microscopy (SEM) was used to verify how the plant extracts affected L. monocytogenes at the microscopic level. Results showed that 12 of the plant extracts had inhibitory activity against L. monocytogenes. Future applications of this study could include the use of these plant extracts as new preservatives to reduce the risk of growth of pathogens and contamination in the food industry from L. monocytogenes.

Easy-To-Synthesize Spirocyclic Compounds Possess Remarkable in Vivo Activity against Mycobacterium tuberculosis.

Society urgently needs new, effective medicines for the treatment of tuberculosis. To kick-start the required hit-to-lead campaigns, the libraries of pharmaceutical companies have recently been evaluated for starting points. The GlaxoSmithKline (GSK) library yielded many high-quality hits, and the associated data were placed in the public domain to stimulate engagement by the wider community. One such series, the spiro compounds, are described here. The compounds were explored by a combination of traditional in-house research and open source methods. The series benefits from a particularly simple structure and a short associated synthetic chemistry route. Many members of the series displayed striking potency and low toxicity, and highly promising in vivo activity in a mouse model was confirmed with one of the analogues. Ultimately the series was discontinued due to concerns over safety, but the associated data remain public domain, empowering others to resume the series if the perceived deficiencies can be overcome.

Adverse Effects of Common Drugs: General Concepts.

Adverse drug reactions (ADRs) contribute to substantial morbidity and mortality and add to rising health care costs. Many ADRs are preventable with appropriate prescribing and monitoring because they often occur as an extension of a drug's mechanism of action or known drug interactions. Patients at higher risk of ADRs include those at the extremes of age, those with multiple comorbidities, those taking multiple drugs, and patients admitted to intensive care units or experiencing transitions of care. Because the risk of ADRs becomes greater as the number of drugs and dietary supplements taken increases, it is imperative that prescribers be vigilant about the prescribing cascade and take steps to discontinue drugs that are likely to be more harmful than helpful. Pharmacists serve as important partners in clinical care environments by conducting comprehensive drug reviews, aiding in drug/dosage selection, and developing therapeutic monitoring plans. Although the potential exists for clinicians to use electronic health record systems to aid in clinical decision making through drug safety decision support tools, computer systems should never replace clinical judgment. Clinicians also are encouraged to report ADRs to the Food and Drug Administration Adverse Event Reporting System.

Adverse Effects of Common Drugs: Children and Adolescents.

Drug use and harms are increasingly common among newborns, infants, children, and adolescents during ambulatory practice, emergency department, and in-hospital treatment, including treatment in pediatric intensive care units. The pharmacokinetic and pharmacodynamic parameters of drugs often are different for children compared with adults and must be considered before prescribing. Drug exposure and the potential for harms also should be considered for fetuses and breastfeeding infants. As with adult patients, a thorough drug and allergy history (including nonprescription drugs and herbal and dietary supplements) should be obtained and reviewed at each medical visit. Children and adolescents are increasingly at risk of drug harm/overdose through accidental or intentional ingestion of nonprescription and prescription drugs (eg, cough and cold preparations, candy-appearing vitamins, stimulants, narcotics). Parents and caregivers should receive training in the proper use, storage, and administration of all drugs. Prescribing clinicians should be vigilant in withholding unnecessary drugs, such as antibiotics for viral infections. When prescribing, clinicians should be aware of common drugs frequently associated with adverse reactions, including stimulants, antipsychotics, analgesics, asthma therapies, acne therapies, and tumor necrosis factor inhibitors. Scientifically based prescribing practices should be used and consultation with evidence-based resources and pharmacists sought as needed.

Adverse Effects of Common Drugs: Dietary Supplements.

Dietary supplement-induced adverse effects often resolve quickly after discontinuation of the offending product, especially in younger patients. The potential for unwanted outcomes can be amplified in elderly patients or those taking multiple prescription drugs, especially where interactions exist with drugs metabolized by cytochrome P450 enzymes. Attributing injury or illness to a specific supplement can be challenging, especially in light of multi-ingredient products, product variability, and variability in reporting, as well as the vast underreporting of adverse drug reactions. Clinicians prescribing a new drug or evaluating a patient with a new symptom complex should inquire about use of herbal and dietary supplements as part of a comprehensive evaluation. Clinicians should report suspected supplement-related adverse effects to the local or state health department, as well as the Food and Drug Administration's MedWatch program (available at https://www.safetyreporting.hhs.gov). Clinicians should consider discussing suspected adverse effects involving drugs, herbal products, or dietary supplements with their community- and hospital-based pharmacists, and explore patient management options with medical or clinical toxicology subspecialists.

Adverse Effects of Common Drugs: Adults.

Although drugs can be an essential and lifesaving component of the care of adult patients, their use frequently is accompanied by adverse effects and life-threatening adverse drug reactions that can result in significant disability and mortality. The potential for drug-related severe morbidity and mortality is compounded during periods of hospitalization, when high-risk drugs such as anticoagulants or insulin are used, and when care in an intensive care unit is required. Patient factors in adults that can increase the risk of drug harms include immunosuppression, cognitive impairment, depression, alcoholism and other substance abuse disorders, chronic kidney disease, hepatic dysfunction, coagulopathies, limited English proficiency, institutional/nursing home care, and underinsurance or lack of insurance. Physician factors that can increase the risk of drug harms include inappropriate prescribing of drugs (including to pregnant and breastfeeding women), failure to appropriately discontinue/deprescribe drugs, insufficient drug reconciliation, failure to coordinate care among multiple prescribing clinicians, and failure to elicit and incorporate into health histories and clinical decision-making the widespread use of nonprescription drugs, herbal products, and dietary supplements.

Evaluation of no-wash calcium assay kits: enabling tools for calcium mobilization.

The no-wash calcium assay kits developed by Molecular Devices Corporation have greatly enhanced the throughput of cell-based calcium mobilization high-throughput screening (HTS) assays and enabled screening using nonadherent cells. The fluorescent imaging plate reader (FLIPR) Calcium 3 Assay Kit, optimal for targets that have proteins or peptides as agonists, has 2 potential drawbacks: 1) a significant downward spike in fluorescence signal upon liquid transfer that can be the same magnitude as the agonist response, making data analysis difficult; and 2) medium removal is required for some targets, which essentially reintroduces a wash step. Several no-wash products were introduced in 2005. The authors compare the Fluo-4 NW Calcium Assay Kit and the BD Calcium Assay Kit with the FLIPR Calcium 3 Assay Kit using human native rhabdomyosarcoma cells expressing the urotensin-II receptor (UT). The BDtrade mark Calcium Assay Kit gives the best performance in the true no-wash mode, in which both agonist and antagonist activity are easily quantified. Although these new products provide additional options for measuring calcium mobilization, the different results observed with each kit, using the UT receptor as an example, suggest that one should characterize all dyes against each target in a systematic way prior to choosing one for HTS.

Praziquantel derivatives I: Modification of the aromatic ring.

Several analogues of the potent anthelmintic praziquantel were prepared with variation in the aromatic ring. The biological activity of these analogues was evaluated and compared against known analogues. Amination of the ring was tolerated while other variations were not. These results have important implications for drug development for schistosomiasis.

Oligomerization of the Na,K-ATPase in cell membranes.

The higher order oligomeric state of the Na,K-ATPase alphabeta heterodimer in cell membranes is the subject of controversy. We have utilized the baculovirus-infected insect cell system to express Na,K-ATPase with alpha-subunits bearing either His(6) or FLAG epitopes at the carboxyl terminus. Each of these constructs produced functional Na,K-ATPase alphabeta heterodimers that were delivered to the plasma membrane (PM). Cells were simultaneously co-infected with viruses encoding alpha-His/beta and alpha-FLAG/beta Na,K-ATPases. Co-immunoprecipitation of the His-tagged alpha-subunit in the endoplasmic reticulum (ER) and PM fractions of co-infected cells by the anti-FLAG antibody demonstrates that protein-protein associations exist between these heterodimers. This suggests the Na,K-ATPase is present in cell membranes in an oligomeric state of at least (alphabeta)(2) composition. Deletion of 256 amino acid residues from the central cytoplasmic loop of the alpha-subunit results in the deletion alpha-4,5-loop-less (alpha-4,5LL), which associates with beta but is confined to the ER. Co-immunoprecipitation demonstrates that when this inactive alpha-4,5LL/beta heterodimer is co-expressed with wild-type alphabeta, oligomers of wild-type alphabeta and alpha-4,5LL/beta form in the ER, but the alpha-4,5LL mutant remains retained in the ER, and the wild-type protein is still delivered to the PM. We conclude that the Na,K-ATPase is present as oligomers of the monomeric alphabeta heterodimer in native cell membranes.