Crisis averted: a world united against the menace of multiple drug-resistant superbugs -pioneering anti-AMR vaccines, RNA interference, nanomedicine, CRISPR-based antimicrobials, bacteriophage therapies, and clinical artificial intelligence strategies to safeguard global antimicrobial arsenal

The efficacy of antibiotics and other antimicrobial agents in combating bacterial infections faces a grave peril in the form of antimicrobial resistance (AMR), an exceedingly pressing global health issue. The emergence and dissemination of drug-resistant bacteria can be attributed to the rampant overuse and misuse of antibiotics, leading to dire consequences such as organ failure and sepsis. Beyond the realm of individual health, the pervasive specter of AMR casts its ominous shadow upon the economy and society at large, resulting in protracted hospital stays, elevated medical expenditures, and diminished productivity, with particularly dire consequences for vulnerable populations. It is abundantly clear that addressing this ominous threat necessitates a concerted international endeavor encompassing the optimization of antibiotic deployment, the pursuit of novel antimicrobial compounds and therapeutic strategies, the enhancement of surveillance and monitoring of resistant bacterial strains, and the assurance of universal access to efficacious treatments. In the ongoing struggle against this encroaching menace, phage-based therapies, strategically tailored to combat AMR, offer a formidable line of defense. Furthermore, an alluring pathway forward for the development of vaccines lies in the utilization of virus-like particles (VLPs), which have demonstrated their remarkable capacity to elicit a robust immune response against bacterial infections. VLP-based vaccinations, characterized by their absence of genetic material and non-infectious nature, present a markedly safer and more stable alternative to conventional immunization protocols. Encouragingly, preclinical investigations have yielded promising results in the development of VLP vaccines targeting pivotal bacteria implicated in the AMR crisis, including Salmonella, Escherichia coli, and Clostridium difficile. Notwithstanding the undeniable potential of VLP vaccines, formidable challenges persist, including the identification of suitable bacterial markers for vaccination and the formidable prospect of bacterial pathogens evolving mechanisms to thwart the immune response. Nonetheless, the prospect of VLP-based vaccines holds great promise in the relentless fight against AMR, underscoring the need for sustained research and development endeavors. In the quest to marshal more potent defenses against AMR and to pave the way for visionary innovations, cutting-edge techniques that incorporate RNA interference, nanomedicine, and the integration of artificial intelligence are currently under rigorous scrutiny.

A validated technique for the analysis of biliary bile acid secretion in donor livers prior to transplantation

Many parameters currently used for the pre-transplant assessment of liver allografts, are not reliable enough in predicting the likelihood of early graft dysfunction or non-function. It is generally accepted that bile secretion is a sign of hepatic function post-transplant and that bile flow shows a close linear relationship to the secretion of bile acids ("apparent choleretic activity"). We have studied bile flow, biliary bile acid concentrations and composition and measured apparent choleretic activity from hepatic bile collected with a new technique under controlled conditions at the time of retrieval from 18 donor livers. More than three samples were collected from each of 13 donors and a total of 65 samples of hepatic bile were analysed. Of these, ten showed typical apparent choleretic activity with a positive slope in the regression line analysis (correlation coefficient of 0.9), validating our collection technique.

Immunoscintigraphy using 111InCyt103 prior to second look laparotomy in ovarian cancer. A pilot study

A prospective pilot study was performed in order to determine the efficacy of 111InCyt103 (ONCOScintr CR/OV) in the detection of the presence and location, or absence of disease among patients with epithelial ovarian cancer who demonstrated no clinical or biochemical (Ca 125: < 35 mu/ml) evidence of disease at the end of first-line therapy. Among 15 patients who underwent second-look laparotomy, the overall accuracy of the test was 60%. The test demonstrated a sensitivity of 62.5% and a specificity of 57.1%. The predictive value of a positive test was 62.5% and of a negative test was 57.1%. The correct location of disease was predicted in 57% of patients with macroscopically appreciable tumors. ONCOScintr CR/OV offers little appreciable advantage over current modalities in discriminating between the presence or absence of disease among patients with epithelial ovarian cancer who demonstrate no clinical evidence of disease at the end of first-line therapy.

Antiglucocorticoids: in vivo assay and evaluation of cortexolone, progesterone, and 6-beta-bromoprogesterone

In vitro antiglucocorticoids (cortexolone and progesterone) were evaluated as in vivo antagonists of dexamethasone-induced increases in liver tyrosine amino transferase (TAT; EC 2.6.1.5), tryptophan oxygenase (TPO; EC 1.13.1.12), and glycogen deposition. Cortexolone antagonized the TPO and glycogen responses to dexamethasone in the liver of adrenalectomized rats but did not significantly influence the induced TAT activity. Progesterone, although toxic at levels approaching those used for cortexolone, was capable of antagonizing the glycogen increase. A new antagonist, 6 beta-bromoprogesterone, was found to be nontoxic and was more potent than cortexolone in blocking the TPO and glycogen responses. These results demonstrate that in vivo antiglucocorticoid activity can be evaluated and suggested significant differences between the sensitivity of TAT induction and that of glycogen or TPO.

Active-site-directed inactivation of aromatase from human placental microsomes by brominated androgen derivatives

Several brominated androgen derivatives were tested for their ability to inactivate microsomal aromatase from term human placenta. In the experimental protocol, the microsomal homogenate was incubated either with androstenedione or a brominated derivative of androstenedione (16alpha-bromo-6-ketoandrostenedione, 16alpha-bromoandrostenedione, 7alpha-(3'-bromoacetoxypropyl)androstenedione, 6alpha-bromoandrostenedione, or 6beta-bromoandrostenedione) and reduced nicotinamide adenine dinucleotide phosphate in a nitrogen saturated buffer composed of glycerol, ethylenediaminetetraacetic acid, and dithiothreitol in tris(hydroxymethyl)aminomethane hydrochloride (pH 7.4) under nitrogen at 4 degrees C with shaking. After the incubation period, the microsomes were recovered by centrifugation and washed once before determining aromatase specific activity. The brominated androgen derivatives which inactivated aromatase were 7alpha-(3'-bromoacetoxypropyl)androstenedione and 6alpha-bromoandrostenedione. The structures of 6alpha- and 6beta-bromoandrostenedione were unequivocally established by single crystal x-ray diffraction techniques. The extent of the enzyme inactivation by 6alpha-bromoandrostenedione was linearly proportional to the logarithm of its concentration. The evidence that this inactivation occurs at the aromatase active site is that androstenedione, when coincubated with 6alpha-bromoandrostenedione, protected aromatase from this inactivation. Progesterone provided much less protection than androstenedione. Furthermore, both 6alpha- and 6beta-bromoandrostenedione are competitive inhibitors of androstenedione aromatization, as determined by a Lineweaver-Burk plot, and 6alpha-bromoandrostenedione gives the same type I cytochrome P-450 binding spectrum with placental microsomes as androstenedione. These data suggest that 6alpha-bromandrostenedione is effective as an active-site-directed inhibitor of placental microsomal aromatase.