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To prevent surgical site infection (SSI), which significantly increases the rate morbidity and mortality, eliminating microorganisms is prominent. Antimicrobial resistance is identified as a global health challenge. This work proposes a new strategy to eliminate microorganisms of deep tissue through electrical stimulation with an ultrasound (US)‐driven implantable, biodegradable, and vibrant triboelectric nanogenerator (IBV‐TENG). After a programmed lifetime, the IBV‐TENG can be eliminated by provoking the on‐demand device dissolution by controlling US intensity with no surgical removal of the device from the body. A voltage of ≈4 V and current of ≈22 µA generated from IBV‐TENG under ultrasound in vitro, confirming inactivating ≈100% of Staphylococcus aureus and ≈99% of Escherichia coli . Furthermore, ex vivo results show that IBV‐TENG implanted under porcine tissue successfully inactivates bacteria. This antibacterial technology is expected to be a countermeasure strategy against SSIs, increasing life expectancy and healthcare quality by preventing microorganisms of deep tissue.

The dual-specificity protein tyrosine phosphatases (PTPs) play integral roles in the regulation of cell signaling. There is a need for new tools to study these phosphatases, and the identification of inhibitors potentially affords not only new means for their study, but also possible therapeutics for the treatment of diseases caused by their dysregulation. However, the identification of selective inhibitors of the protein phosphatases has proven somewhat difficult. PTP localized to mitochondrion 1 (PTPMT1) is a recently discovered dual-specificity phosphatase that has been implicated in the regulation of insulin secretion. Screening of a commercially available small-molecule library yielded alexidine dihydrochloride, a dibiguanide compound, as an effective and selective inhibitor of PTPMT1 with an in vitro concentration that inhibits response by 50% of 1.08 M. A related dibiguanide analog, chlorhexidine dihydrochloride, also significantly inhibited PTPMT1, albeit with lower potency, while a monobiguanide analog showed very weak inhibition. Treatment of isolated rat pancreatic islets with alexidine dihydrochloride resulted in a dosedependent increase in insulin secretion, whereas treatment of a pancreatic ␤-cell line with the drug affected the phosphorylation of mitochondrial proteins in a manner similar to genetic inhibition of PTPMT1. Furthermore, knockdown of PTPMT1 in rat islets rendered them insensitive to alexidine dihydrochloride treatment, providing evidence for mechanism-based activity of the inhibitor. Taken together, these studies establish alexidine dihydrochloride as an effective inhibitor of PTPMT1, both in vitro and in cells, and support the notion that PTPMT1 could serve as a pharmacological target in the treatment of type II diabetes.

Scoparone is a major component of the shoot of Artemisia capillaris (Compositae), which has been used for the treatment of hepatitis and biliary tract infection in oriental countries. In the present study we observed that, scorparone exhibited no cytotoxic effect in unstimulated macrophages, but reduced the release of nitric oxide (NO) and prostaglandin E2 (PGE2) upon stimulation by IFN-gamma/LPS or LPS. The inhibitory effects were found to be in conjuction with the suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in IFN-gamma/LPS stimulated RAW 264.7 cells. Moreover, scoparone also attenuated the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 in LPS-stimulated RAW264.7 cells. These results suggest that scoparone decreases the production of the inflammatory mediators such as NO and PGE2 in macrophages by inhibiting iNOS and COX-2 expression.

By using mini-Tn5 transposon mutagenesis, two mutants of Pseudomonas putida ATCC 12633 were isolated which showed a marked increase in their sensitivity to carbon starvation; these mutants are presumably affected in the Pex type of proteins that P. putida induces upon carbon starvation (M. Givskov, L. Eberl, and S. Molin, J. Bacteriol. 176:4816-4824, 1994). The affected genes in our mutants were induced about threefold upon carbon starvation. The promoter region of the starvation gene in the mutant MK107 possessed a strong 54 -type promoter sequence, and deletion analysis suggested that this was the major promoter regulating expression; this was confirmed by transcript mapping in rpoN ؉ and rpoN mutant backgrounds. The deletion analysis implicated a sequence upstream of the 54 promoter, as well as a region downstream of the transcription start site, in the functioning of the promoter. Two 70 -type Pribnow boxes were also detected in the promoter region, but their transcriptional activity in the wild type was very weak. However, in a 54 -deficient background, these promoters became stronger. The mechanism and possible physiological role of this phenomenon and the possibility that the sequence upstream of the 54 promoter may have a role in carbon sensing are discussed.Recent studies have established that, contrary to earlier implicit assumptions, the so-called nondifferentiating bacteria do undergo an elaborate process of molecular realignment upon starvation which leads to the development of a resistant cellular state. Such differentiated cells possess markedly enhanced resistance to a variety of individual stresses (21,22). These studies have been most advanced in Escherichia coli (15,25,38), but evidence is accumulating that similar processes operate in marine Vibrio species (43) and in Salmonella typhimurium (50). This differentiation involves expression of several temporal classes of starvation genes that code for special resistance proteins and depends on alternate factors. In E. coli, two factors, 38 and 32 , have been implicated in the starvation response, with the former playing a specially critical role (20,27,40). Evidence has also been presented that these factors are regulated primarily at the posttranscriptional level by a mechanism that involves mRNA secondary structure (32, 39) and that carbon starvation in E. coli might be sensed through the accumulation of homoserine lactone (18).Given the ecological niches of E. coli and S. typhimurium, it is probable that they experience periods of feast and famine. Bacteria in many other habitats probably experience an even greater degree of nutrient scarcity with survival being mostly a matter of coping with prolonged starvation. Members of the genus Pseudomonas inhabit soil and groundwater environments which typically are very nutrient poor (11, 16) and thus belong to the latter class of bacteria. Earlier studies established the remarkable starvation resistance of many species of this genus (8, 36). More recently, Molin and his coworkers have shown that...