https://www.cell.com/cell/pdf/S0092-8674(04)00661-0.pdf

Recognition of Commensal Microflora by Toll-Like Receptors Is Required for Intestinal Homeostasis

Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait.

https://www.physiology.org/doi/pdf/10.1152/physrev.00044.2003

Melanin Pigmentation in Mammalian Skin and Its Hormonal Regulation

Given the trillions of microbes that inhabit the mammalian intestines, the host immune system must constantly maintain a balance between tolerance to commensals and immunity against pathogens to avoid unnecessary immune responses against otherwise harmless bacteria. Misregulated responses can lead to inflammatory bowel diseases such as ulcerative colitis or Crohn's disease. The mechanisms by which the immune system maintains this critical balance remain largely undefined. Here, we demonstrate that the short-chain fatty acid n-butyrate, which is secreted in high amounts by commensal bacteria, can modulate the function of intestinal macrophages, the most abundant immune cell type in the lamina propria. Treatment of macrophages with n-butyrate led to the down-regulation of lipopolysaccharide-induced proinflammatory mediators, including nitric oxide, IL-6, and IL-12, but did not affect levels of TNF-α or MCP-1. These effects were independent of toll-like receptor signaling and activation of G-protein-coupled receptors, two pathways that could be affected by short-chain fatty acids. In this study, we provide several lines of evidence that suggest that these effects are due to the inhibition of histone deacetylases by n-butyrate. These findings elucidate a pathway in which the host may maintain tolerance to intestinal microbiota by rendering lamina propria macrophages hyporesponsive to commensal bacteria through the down-regulation of proinflammatory effectors.

https://www.pnas.org/content/pnas/111/6/2247.full.pdf

The microbial metabolite butyrate regulates intestinal macrophage function via histone deacetylase inhibition

https://www.jidonline.org/article/S0022-202X(15)33382-0/pdf

Keratinocyte–Fibroblast Interactions in Wound Healing

In wound healing, a variety of mediators have been identified throughout the years. The mediators discussed here comprise growth factors, cytokines and chemokines. These mediators act via multiple (specific) receptors to facilitate wound closure. As research in the last years has led to many new findings, there is a need to give an overview on what is known, and on what might possibly play a role as a molecular target for future wound therapy. This review aims to keep the reader up to date with selected important and novel findings regarding growth factors, cytokines and chemokines in wound healing.

Cytokines, chemokines and growth factors in wound healing

To clarify interleukin (IL)-6 roles in wound healing, we prepared skin excisions in wild-type (WT) and IL-6-deficient BALB/c [knockout (KO)] mice. In WT mice, the wound area was reduced to 50% of original size at 6 days after injury. Microscopically, leukocyte infiltration was evident at wound sites. Furthermore, the re-epithelialization rate was approximately 80% at 6 days after injury with increases in angiogenesis and hydroxyproline contents. The gene expression of IL-1, chemokines, adhesion molecules, transforming growth factor-beta1, and vascular endothelial growth factor was enhanced at the wound sites. In contrast, the enhanced expression of these genes was significantly reduced in KO mice. Moreover, in KO mice, the reduction of wound area was delayed with attenuated leukocyte infiltration, re-epithelialization, angiogenesis, and collagen accumulation. Finally, the administration of a neutralizing anti-IL-6 monoclonal antibody significantly delayed wound closure in WT mice. These observations suggest that IL-6 has crucial roles in wound healing, probably by regulating leukocyte infiltration, angiogenesis, and collagen accumulation.

https://jlb.onlinelibrary.wiley.com/doi/epdf/10.1189/jlb.0802397

Essential involvement of IL-6 in the skin wound-healing process as evidenced by delayed wound healing in IL-6-deficient mice.

Sex determination by polymerase chain reaction on mummies discovered at Taklamakan desert in 1912.

( Abstract Analyses of several volatile substances were already reported, including ethanol (2), diethylether, chloroform, and toluene (3), nitrous oxide, 1,1,1-trichloroethane, cresol, and acetone (4), and thinner components (toluene, ethylbenzene, and xylene) (5). This report describes the analysis of four kinds of volatile anesthetics (halothane, enflurane, isoflurane, and sevoflurane) commonly used in surgical operations by pulse-heating gas chromatography-mass spectrometry (GC-MS) using minute biological samples.

Determination of the Volatile Anesthetics Halothane, Enflurane, Isoflurane, and Sevoflurane in Biological Specimens by Pulse-Heating GC-MS

Methamphetamine (MA) was analyzed using formalin-fixed organ tissues from experimental animals and an autopsied cadaver. The brain, lung, liver, kidney and skeletal muscles of rabbits that had been administered MA were collected, and then fixed with a non-buffered 10% formalin solution at room temperature (10-20 degrees C) for five different fixation periods (1, 3, 7, 14 and 28 days). After the Extrelut column extraction, MA was derivatized using anhydrous trifluoroacetic acid (TFA) and analyzed by GC-MS using a DB-17 column. MA-TFA in the eluates from the organ tissues after the formalin-fixation could be identified by GC-MS. Even one day after the formalin-fixation, concentrations of MA in the fixed organ tissues already significantly decreased to 1.3-3.1% when compared with those of MA in the non-fixed tissues, and to 0.04-0.4% in all of the fixed organ tissues at 28 days after the fixation. Moreover, MA in the organ eluates from the autopsied male cadaver after one-month formalin-fixation was qualitatively detected. These results obviously show the usefulness of MA detection using formalin-fixed organs in the practice of forensic medicine and police science.

Toxicological analysis for drugs and poisons using the formalin-fixed organ tissues. 1. Methamphetamine

Screening of volatile substances and determination of toluene (a thinner component) in the blood and urine in emergency medical care and autopsy cases by the pulse heating method.

Z. Lin

Papers

Essential involvement of IL-6 in the skin wound-healing process as evidenced by delayed wound healing in IL-6-deficient mice.

Sex determination by polymerase chain reaction on mummies discovered at Taklamakan desert in 1912.

Determination of the Volatile Anesthetics Halothane, Enflurane, Isoflurane, and Sevoflurane in Biological Specimens by Pulse-Heating GC-MS

Toxicological analysis for drugs and poisons using the formalin-fixed organ tissues. 1. Methamphetamine

Screening of volatile substances and determination of toluene (a thinner component) in the blood and urine in emergency medical care and autopsy cases by the pulse heating method.