- A new protocol and standard of care for managing open crown margins. [Journal Article]
- GDGen Dent 2019 Mar-Apr; 67(2):19-22
- Open margins on indirect restorations (such as crowns) are the bane of dentists. Judging margins is a subjective undertaking, and there is no agreement among dentists on "how open is open?" Board act…
Open margins on indirect restorations (such as crowns) are the bane of dentists. Judging margins is a subjective undertaking, and there is no agreement among dentists on "how open is open?" Board actions and lawsuits commonly include charges concerning open margins. Immediate replacement of the offending restoration is claimed as the standard of care, particularly when litigation or state dental board actions are involved. However, repair and monitoring of margins are options that have recently become available. These approaches have been widely accepted and are less invasive alternatives to immediate replacement. Silver diamine fluoride (SDF) has provided new options for the management of margins. SDF, which is inexpensive and easy to apply, kills pathogens; hardens softened dentin (making it more acid and abrasion resistant); and does not stain sound dentin, enamel, or porcelain. SDF does stain any caries black. Except for those with demonstrably grossly open margins, restorations with marginal defects can and should be treated conservatively. Repairing or resealing, where possible, along with continued monitoring of all indirect restorations, has now become the standard of care. If caries develops, the tooth can often be conservatively treated by applying a layer of SDF. Only within the esthetic zones would the option of repair or replacement of the restoration be necessary.
- Discovery and Structural Optimization of Acridones as Broad-Spectrum Antimalarials. [Journal Article]
- JMJ Med Chem 2019 Apr 11; 62(7):3475-3502
- Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a…
Malaria remains one of the deadliest diseases in the world today. Novel chemoprophylactic and chemotherapeutic antimalarials are needed to support the renewed eradication agenda. We have discovered a novel antimalarial acridone chemotype with dual-stage activity against both liver-stage and blood-stage malaria. Several lead compounds generated from structural optimization of a large library of novel acridones exhibit efficacy in the following systems: (1) picomolar inhibition of in vitro Plasmodium falciparum blood-stage growth against multidrug-resistant parasites; (2) curative efficacy after oral administration in an erythrocytic Plasmodium yoelii murine malaria model; (3) prevention of in vitro Plasmodium berghei sporozoite-induced development in human hepatocytes; and (4) protection of in vivo P. berghei sporozoite-induced infection in mice. This study offers the first account of liver-stage antimalarial activity in an acridone chemotype. Details of the design, chemistry, structure-activity relationships, safety, metabolic/pharmacokinetic studies, and mechanistic investigation are presented herein.
- Extracellular polymeric substance (EPS)-degrading enzymes reduce staphylococcal surface attachment and biocide resistance on pig skin in vivo. [Journal Article]
- PlosPLoS One 2018; 13(10):e0205526
- Staphylococcal extracellular polymeric substances (EPS) such as extracellular DNA (eDNA) and poly-N-acetylglucosamine surface polysaccharide (PNAG) mediate numerous virulence traits including host co…
Staphylococcal extracellular polymeric substances (EPS) such as extracellular DNA (eDNA) and poly-N-acetylglucosamine surface polysaccharide (PNAG) mediate numerous virulence traits including host colonization and antimicrobial resistance. Previous studies showed that EPS-degrading enzymes increase staphylococcal biocide susceptibility in vitro and in vivo, and decrease virulence in animal models. In the present study we tested the effect of EPS-degrading enzymes on staphylococcal skin colonization and povidone iodine susceptibility using a novel in vivo pig model that enabled us to colonize and treat 96 isolated areas of skin on a single animal in vivo. To quantitate skin colonization, punch biopsies of colonized areas were homogenized, diluted, and plated on agar for colony forming unit enumeration. Skin was colonized with either Staphylococcus epidermidis or Staphylococcus aureus. Two EPS-degrading enzymes, DNase I and the PNAG-degrading enzyme dispersin B, were employed. Enzymes were tested for their ability to inhibit skin colonization and detach preattached bacteria. The effect of enzymes on the susceptibility of preattached S. aureus to killing by povidone iodine was also measured. We found that dispersin B significantly inhibited skin colonization by S. epidermidis and detached preattached S. epidermidis cells from skin. A cocktail of dispersin B and DNase I detached preattached S. aureus cells from skin and increased their susceptibility to killing by povidone iodine. These findings suggest that staphylococcal EPS components such as eDNA and PNAG contribute to skin colonization and biocide resistance in vivo. EPS-degrading enzymes may be a useful adjunct to conventional skin antisepsis procedures in order to further reduce skin bioburden.
- Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest. [Randomized Controlled Trial]
- NEJMN Engl J Med 2016 May 05; 374(18):1711-22
- CONCLUSIONS: Overall, neither amiodarone nor lidocaine resulted in a significantly higher rate of survival or favorable neurologic outcome than the rate with placebo among patients with out-of-hospital cardiac arrest due to initial shock-refractory ventricular fibrillation or pulseless ventricular tachycardia. (Funded by the National Heart, Lung, and Blood Institute and others; ClinicalTrials.gov number, NCT01401647.).
- Trial of Continuous or Interrupted Chest Compressions during CPR. [Randomized Controlled Trial]
- NEJMN Engl J Med 2015 Dec 03; 373(23):2203-14
- CONCLUSIONS: In patients with out-of-hospital cardiac arrest, continuous chest compressions during CPR performed by EMS providers did not result in significantly higher rates of survival or favorable neurologic function than did interrupted chest compressions. (Funded by the National Heart, Lung, and Blood Institute and others; ROC CCC ClinicalTrials.gov number, NCT01372748.).
- Medical Microbiology: Bacillus [BOOK]
- BOOKUniversity of Texas Medical Branch at Galveston: Galveston (TX)
- Bacillus species are aerobic, sporulating, rod-shaped bacteria that are ubiquitous in nature. Bacillus anthracis, the agent of anthrax, is the only obligate Bacillus pathogen in vertebrates. Bacillus…
Bacillus species are aerobic, sporulating, rod-shaped bacteria that are ubiquitous in nature. Bacillus anthracis, the agent of anthrax, is the only obligate Bacillus pathogen in vertebrates. Bacillus larvae, B lentimorbus, B popilliae, B sphaericus, and B thuringiensis are pathogens of specific groups of insects. A number of other species, in particular B cereus, are occasional pathogens of humans and livestock, but the large majority of Bacillus species are harmless saprophytes. Anthrax has afflicted humans throughout recorded history. The fifth and sixth plagues of Egypt described in Exodus are widely believed to have been anthrax. The disease was featured in the writings of Virgil in 25 BC and was familiar in medieval times as the Black Bane. It was from studies on anthrax that Koch established his famous postulates in 1876, and vaccines against anthraxthe best known being that of Pasteur (1881)were among the first bacterial vaccines developed. Bacillus species are used in many medical, pharmaceutical, agricultural, and industrial processes that take advantage of their wide range of physiologic characteristics and their ability to produce a host of enzymes, antibiotics, and other metabolites. Bacitracin and polymyxin are two well-known antibiotics obtained from Bacillus species. Several species are used as standards in medical and pharmaceutical assays. The spores of the obligate thermophile B stearothermophilus are used to test heat sterilization procedures, and B subtilis subsp globigii, which is resistant to heat, chemicals, and radiation, is widely used to validate alternative sterilization and fumigation procedures. Certain Bacillus species are important in the natural or artificial degradation of waste products. Some Bacillus insect pathogens are used as the active ingredients of insecticides. Because the spores of many Bacillus species are resistant to heat, radiation, disinfectants, and desiccation, they are difficult to eliminate from medical and pharmaceutical materials and are a frequent cause of contamination. Bacillus species are well known in the food industries as troublesome spoilage organisms.
- Convenience, the bane of our existence, and other barriers to donating. [Journal Article]
- TTransfusion 2006; 46(4):545-53
- CONCLUSIONS: Inconvenience is a major barrier to donating, suggesting that mobile collections and increased hours of operation might help recapture lapsed donors. The finding that lapsed minority donors were more likely to give bad treatment and poor staff skills as important reasons to not donate is disconcerting in light of the changing donor demographics and increased efforts to recruit these donors.