Early laparotomy wound failure as the mechanism for incisional hernia formation.

Background: Incisional hernia is the most common complication of abdominal surgery leading to reoperation. In the United States, 200,000 incisional hernia repairs are performed annually, often with significant morbidity. Obesity is increasing the risk of laparotomy wound failure.

Reversibility of abdominal wall atrophy and fibrosis after primary or mesh herniorrhaphy.

Objective: To determine whether primary or mesh herniorrhaphy reverses abdominal wall atrophy and fibrosis associated with hernia formation.

Background: We previously demonstrated that hernia formation is associated with abdominal wall atrophy and fibrosis after 5 weeks in an animal model.

Methods: A rat model of chronic incisional hernia was used.

Loss of mechanical strain impairs abdominal wall fibroblast proliferation, orientation, and collagen contraction function.

Background: Laparotomy wound load forces are reduced when dehiscence and incisional hernia formation occur. The purpose of this study was to determine the effects of strain loss on abdominal fascial fibroblast proliferation, orientation, and collagen compaction function.

Methods: Cultured rat linea alba fibroblasts were subjected to continuous cyclic strain (CS), CS interrupted at 24 or 48 hours followed by culture at rest (IS-24 and IS-48) or were cultured without mechanical strain (NS).

Impaired laparotomy wound healing in obese rats.

Background: Obesity increases the risk of laparotomy dehiscence and incisional hernia. The aim of this study was to measure the biological effect of obesity on laparotomy wound healing and the formation of incisional hernias.

Methods: Normal-weight Sprague-Dawley (SD) and obese Zucker rats were used in an established laparotomy wound healing and incisional ventral hernia model.

The use of amnion-derived cellular cytokine solution to improve healing in acute and chronic wound models.

Objective: Growth factors demonstrate mixed results improving wound healing. Amnion-derived multipotent cells release physiologic levels of growth factors and tissue inhibitors of metalloproteinases. This solution was tested in models of acute and chronic wound healing.

Amnion-derived multipotent progenitor cells increase gain of incisional breaking strength and decrease incidence and severity of acute wound failure.

Objective: Acute wound failure is a common complication following surgical procedures and trauma. Laparotomy wound failure leads to abdominal dehiscence and incisional hernia formation. Delayed recovery of wound-breaking strength is one mechanism for laparotomy wound failure.

Promoter elements responsible for antioxidant regulation of MCP-1 gene expression.

Monocyte chemoattractant protein-1 (MCP-1) is produced by different cells in response to inflammatory stimulation. In the present study, a series of human MCP-1 promoter reporter genes were constructed to illustrate elements involved in antioxidant dimethyl sulfoxide (DMSO) inhibition of MCP-1 gene expression. MCP-1 secretion and mRNA expression and transcription activity stimulated by TNF-alpha or IL-1beta were significantly inhibited by 1% DMSO in alveolar type II epithelial cells (A549).

Mechanisms of oxidant regulation of monocyte chemotactic protein 1 production in human whole blood and isolated mononuclear cells.

Previous work has demonstrated that reactive oxygen intermediates (ROIs) play an important regulatory role in the induction of monocyte chemotactic protein 1 (MCP-1) in certain cells. This study investigated the mechanisms of ROI regulation of MCP-1 gene expression in whole blood and isolated peripheral blood mononuclear cells (PBMCs). The antioxidants dimethyl sulfoxide (DMSO), N-acetyl cysteine, and dimethyl thiourea significantly inhibited lipopolysaccharide (LPS)-induced MCP-1 production in either whole blood or isolated blood cells.

Neutrophils as firemen, production of anti-inflammatory mediators by neutrophils in a mixed cell environment.

Neutrophils represent critical components of the innate immune system that bear primary responsibility for phagocytosis and killing of invading pathogens. Following stimulation of human whole blood, robust production of multiple cytokines and cytokine inhibitors occurs. We attempted to define the cell population responsible for the synthesis of different mediators by first stimulating whole blood and then isolating pure populations of granulocytes and monocytes.

Mechanisms of dimethyl sulfoxide augmentation of IL-1 beta production.

Expression of the inflammatory cytokine IL-1beta occurs in various inflammatory diseases, and IL-1beta production is regulated at multiple levels. There are conflicting reports about the effects of antioxidants on IL-1beta production. In this study, we investigated the regulatory role of the antioxidant DMSO on LPS-stimulated IL-1beta gene expression in human PBMC and in vivo.

Relative cytokine and cytokine inhibitor production by mononuclear cells and neutrophils.

Mononuclear cells represent the major source of cytokines in blood; however, it has been postulated that neutrophils may produce and/or release modest amounts of cytokines. In this study, we compared the production of cytokines and cytokine inhibitors in lipopolysaccharide (LPS)-stimulated whole blood, peripheral blood mononuclear cells (PBMCs), and neutrophils (PMNs) separated by density gradient centrifugation. Contamination of PBMCs in the isolated PMNs was less than 0.

Production and secretion of calcitonin gene-related peptide from human lymphocytes.

Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide, which is mainly present in primary sensory nerves. Although our previous study has shown that rat lymphocytes can synthesize beta-CGRP, there is no evidence demonstrating whether CGRP can be synthesized by human lymphocytes. In this study, the production of CGRP from human lymphocytes from spleen and blood were investigated by using CGRP-specific radioimmunoassay (RIA), and RNase protection assay (RPA).

Comparison of calcitonin gene-related peptide release from rat lymphocytes and dorsal root ganglia neurons.

Calcitonin gene-related peptide (CGRP), a neuropeptide contained in primary sensory neurons, has been demonstrated to be synthesized and released by rat lymphocytes in our previous studies. In this study, the release properties and molecular characteristics of CGRP such as immunoreactivity (CGRP-LI) from lymphocytes were compared with those from dorsal root ganglia (DRG) neurons by using CGRP-specific RIA, reverse-phase HPLC, and RT-PCR. Con A and IL-2 could trigger CGRP-LI release from lymphocytes in a time-dependent manner.