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Melatonin therapy after hemorrhagic shock improves liver function, hepatic perfusion, redox state, and hepatic integrity. With respect to liver function, beneficial effects of the pineal hormone seem to be dependent on melatonin receptor activation.

Using a 445-nm semiconductor laser for tissue incision, an effective cut is expected due to the special absorption properties of blue laser light in soft tissues. The aim of the present study was the histological evaluation of tissue samples after incision with a 445-nm diode laser. Forty soft tissue specimens were obtained from pork oral mucosa and mounted on a motorized linear translation stage. The handpiece of a high-frequency surgery device, a 970-nm semiconductor laser, and a 445-nm semiconductor laser were connected to the slide, allowing a constant linear movement (2 mm/s) and the same distance of the working tip to the soft tissue's surface. Four incisions were made each: (I) 970-nm laser with conditioned fiber tip, contact mode at 3-W cw; (II-III): 445-nm laser with non-conditioned fiber tip, contact mode at 2-W cw, and non-contact mode (1 mm) at 2 W; and (IV): high-frequency surgery device with straight working tip, 90° angulation, contact mode at 50 W. Histological analysis was performed after H&E staining of the embedded specimens at 35-fold magnification. The comparison of the incision depths showed a significant difference depending on the laser wavelength and the selected laser parameters. The highest incision depth was achieved with the 445-nm laser contact mode (median depth 0.61 mm, min 0.26, max 1.17, interquartile range 0.58) (p < 0.05) with the lowest amount of soft tissue denaturation (p < 0.05). The lowest incision depth was measured for the high-frequency surgical device (median depth 0.36 mm, min 0.12, max 1.12, interquartile range 0.23) (p < 0.05). Using a 445-nm semiconductor laser, a higher cutting efficiency can be expected when compared with a 970-nm diode laser and high-frequency surgery. Even the 445-nm laser application in non-contact mode shows clinically acceptable incision depths without signs of extensive soft tissue denaturation.

Dobutamine is recommended for the treatment of sepsis-related circulatory failure in international guidelines. Furthermore, dobutamine has been demonstrated to improve liver function and hepatic perfusion after experimental hemorrhagic shock. Yet, it is unknown whether dobutamine may also induce hepatoprotective effects in sepsis. This study was designed to investigate the effect of dobutamine on survival, hepatic function, and microcirculation after polymicrobial sepsis in rat. Under general anesthesia, male Sprague-Dawley rats (n = 25/group) underwent pretreatment with dobutamine (10 μg/kg per minute) in the presence or absence of β1-receptor antagonist esmolol (500 μg/kg per minute), esmolol alone, or vehicle for 6 h, before induction of sepsis (cecal ligation and incision [CLI]). Sham-operated animals were treated likewise but underwent no CLI. Five hours after CLI, either liver function was assessed by plasma disappearance rate of indocyanine green (n = 5/group), or intravital microscopy was performed (n = 5/group) for evaluation of hepatic perfusion index and hepatic integrity (as propidium iodide-stained cells per field). Alternatively, survival time after induction of CLI was monitored under general anesthesia (n = 15/group). Compared with controls, dobutamine pretreatment significantly improved plasma disappearance rate of indocyanine green (13.8% ± 4.1% vs. 20.6% ± 4.6%; P = 0.029), hepatic perfusion index (275.0 ± 126.1 vs. 703.5 ± 177.4 pL/s per mm; P < 0.001), hepatocellular injury (22.2 ± 6.7 vs. 6.4 ± 3.1 cells per field; P < 0.001), and survival time (326 ± 20 vs. 603 ± 41 min; P < 0.001). Coadministration of esmolol abolished the protective effect of dobutamine completely. Our results indicate that pretreatment with dobutamine may improve survival, liver function, and hepatic microcirculation after polymicrobial sepsis in rat via β1-adrenoceptor activation. Dobutamine could therefore play a relevant role for hepatoprotection under septic conditions.

Since the first description of bisphosphonate-related osteonecrosis of the jaw (BRONJ), numerous research groups have focused on possible pathological mechanisms including the suppression of the bone turnover of the jaw, antiangiogenic effects and soft tissue toxicity. In our review we focused on summarizing the role of the soft tissues in the development and progression of BRONJ. The biological behavior of fibroblasts can be significantly influenced by bisphosphonates (BP) such as a concentration dependent reduction of cell viability. High concentrations of BP can induce apoptosis and necrosis of the cells. Comparable effects could be detected for keratinocytes. Compared to non-nitrogen containing bisphosphonates, nitrogen-containing BP have worse effects on cell biology by blocking the mevalonate pathway. Further, the cell architecture and expression levels of several genes and proteins are significantly disturbed by BP. These inhibitory effects of BP are in accordance with BP-related reduced angiogenesis and neovascularization and could underline the hypothesis that inhibition of fibroblasts and keratinocytes results in delayed wound healing and can induce and trigger BRONJ.

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Based on the conditions of this study, laser photochemotherapy may be able to raise the cytotoxicity of cisplatin and zolendronic acid in benign and malignant bone cells. This could be of interest in the development of new therapeutic treatment modalities against neoplastic bone diseases like osteosarcoma.

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