Protease inhibitor reduces loss of tensile strength in rat anastomosis with peritonitis

BACKGROUND: The tensile strength in intestinal anastomoses decreases postoperatively in association with degradation of the extracellular matrix, and these changes would be expected to be more intense in the presence of peritonitis. MATERIALS AND METHODS: In this study, we investigated extracellular matrix degradation and tensile strength in a rat model of intestinal anastomosis with peritonitis. In the chemical peritonitis model, peritonitis was induced 24 h earlier with intraperitoneal HCl. A serine protease inhibitor, nafamostat mesilate (NM), was given intraperitoneally to some animals every 12 h from immediately after the operation for 3 days. Immunostaining was performed by the standard streptavidin-biotin-peroxidase method after fibronectin (Fn) and factor XIII antigen retrieval on paraformaldehyde-fixed, paraffin-embedded tissue sections. RESULTS: In comparison with controls, administration of NM reduced the loss of tensile strength on Day 3 in a dose-dependent manner, and high-dose NM (20/mg/kg) significantly prevented the loss of tensile strength on Day 3 (P < 0. 05). In the control group, degradation of the collagen layer in the anastomosis was associated with disappearance of Fn and factor XIII staining on Day 3. The administration of NM attenuated these changes with intense immunostaining for Fn and factor XIII seen particularly between collagen fibers on both sides of the anastomosis on Day 3. In the chemical peritonitis model, administration of NM also significantly prevented the loss of tensile strength on Day 3 without disappearance of collagen fibers. CONCLUSION: These findings suggest that NM may be clinically useful for preventing intestinal leakage, particularly when anastomoses are performed under protease-activating conditions, such as intestinal edema and inflammation.     

A Novel Nonradioactive Method for Measuring Aromatase Activity Using a Human Ovarian Granulosa-Like Tumor Cell Line and an Estrone ELISA

The following sentences should have read: Results, Reproducibility     

Rattlesnake venom induces apoptosis by stimulating PC-PLC and upregulating the expression of integrin beta4, P53 in vascular endothelial cells.

In the previous studies, we found that phosphatidylcholine-specific phospholipase C (PC-PLC) was implicated in apoptosis induced by rattlesnake venom in vascular endothelial cells (VEC) [Biochem. Biophys. Res. Commun. (1997b) 223, 182]. In order to find out other signal elements in this pathway and the mechanisms by which PC-PLC mediates apoptosis induced by rattlesnake venom in VEC, the expression of integrin beta4 and P53 was evaluated when the activity of PC-PLC was suppressed by D609 (tricyclodecan-9-yl-xanthogenate), a specific inhibitor of this enzyme. The increase of integrin beta4 and P53 expression induced by the venom was markedly suppressed when apoptosis of VEC was inhibited by D609. The data indicated that integrin beta4 and P53 play important roles in signal transduction of apoptosis induced by rattlesnake venom, and that PC-PLC might regulate apoptosis by up-regulating the expression of integrin beta4 and P53 in VEC.     

Molecular diversity of TEX101, a marker glycoprotein for germ cells monitored with monoclonal antibodies: variety of the molecular characteristics according to subcellular localization within the mouse testis

TEX101 was characterized as a unique germ cell marker molecule using the specific monoclonal antibody (mAb), TES101. Although this mAb has strong affinity/specificity for TEX101, TES101 mAb loses its reactivity under reducing conditions. In this study, we have generated new mAbs against TEX101 to compensate for the shortcomings of the TES101 mAb using different approaches. First, we immunized mice with the antigen on a baculovirus expression system and isolated new anti-TEX101 mAbs, 6002 and 6035. Second, we raised the mAb Ts4 from spleen cells of an immunologically naive old mouse. Western blot analysis revealed that the new mAbs possess immunoreactivity under reducing/non-reducing conditions. Immunopositive staining of the mAbs against Bouin-fixed sections was observed in spermatocytes, spermatids and testicular spermatozoa, but not in other cells, similar to paraformaldehyde (PFA)-fixed frozen sections stained with TES101 as previously reported. However, whereas the mAbs 6002/6035 mainly showed immunoreactivity only in spermatocytes in PFA-fixed frozen sections, the reactivity of the mAbs to spermatids and testicular spermatozoa was clearly recovered when the PFA-fixed sections were autoclaved or treated with SDS. Peptide mapping and deglycosylation analysis indicated that the epitopes for TES101, 6002 and 6035 are located within TEX101(25-94), whereas Ts4 recognized N-linked carbohydrate moieties on TEX101 in Triton X-100-soluble mouse testicular extracts but not in the extracellular or water-soluble fractions. These results suggest strongly that the molecular association or structure of N-linked carbohydrate moieties of TEX101 varies according to its subcellular localization within the seminiferous tubules. These new mAbs will be valuable tools for further analysis of TEX101, including its function(s).     

Lack of evidence for the involvement of catecholaminergic mechanisms in the behavioral anti-methamphetamine effect of L-histidine in the mouse

The effects of L-histidine (HIS) on the hypermotility and the changes in brain monoamine dynamics induced by methamphetamine (MAMP) were examined in mice. HIS (1000 mg/kg) completely inhibited the hypermotility induced by MAMP (1 mg/kg). MAMP (1 mg/kg) significantly increased the dopamine level and decreased the 3,4-dihydroxyphenylacetic acid level. MAMP (5 and 10 mg/kg) also produced changes in the levels of noradrenaline, serotonin and their metabolites. HIS administered alone caused no significant changes in the levels of these amines and metabolites, nor did it affect MAMP-induced alterations in monoamine dynamics. These results suggest that catecholaminergic mechanisms are not involved in the behavioral anti-MAMP action of HIS.     

Fast magnetic resonance imaging of liver.

Recent magnetic resonance (MR) units with a stronger gradient system have allowed various fast MR imaging techniques to develop. These fast scan techniques have easily realized breath-holding acquisition in the liver and the image quality has been greatly improved without sacrificing spatial resolution. The majority of the fast imaging techniques have been devoted to T2-weighted imaging to obtain useful T2-weighted images in the shortest possible time. Among the fast sequences, fast spin-echo (FSE) sequence is the most promising technique and allows high-quality T2-weighted images with reduced motion artifacts. However, FSE sequences using multiple refocused pulses may essentially realize only poor soft-tissue contrast due to magnetization transfer and T2-filtering effects, and therefore, echo-planar (EP) imaging is expected to provide high image contrast. In addition, single-shot EP imaging allows even diffusion-weighted (DW) and perfusion-weighted (PW) imaging in the liver due to its short scanning time. Recent development of fast gadolinium-enhanced 3D MR angiography has also impacted liver imaging. Combined with such gadolinium-enhanced 3D-MRA sequences and zerofilling image interpolation technique, biphasic gadolinium-enhanced 3D-MRA (whole-liver dynamic MR imaging in the arterial phase and MR portography in the portal phase) can be obtained.     

Stromal cell-derived factor 1 (SDF-1) and its receptor CXCR4 in the formation of postburn hypertrophic scar (HTS)

Recent data support the involvement of stromal cell-derived factor 1 (SDF-1) in the homing of bone marrow-derived stem cells to wound sites during skeletal, myocardial, vascular, lung, and skin wound repair as well as some fibrotic disorders via its receptor CXCR4. In this study, the role of SDF-1/CXCR4 signaling in the formation of hypertrophic scar (HTS) following burn injury and after treatment with systemic interferon α2b (IFNα2b) is investigated. Studies show SDF-1/CXCR4 signaling was up-regulated in burn patients, including SDF-1 level in HTS tissue and serum as well as CD14+ CXCR4+ cells in the peripheral blood mononuclear cells. In vitro, dermal fibroblasts constitutively expressed SDF-1 and deep dermal fibroblasts expressed more SDF-1 than superficial fibroblasts. Lipopolysaccharide increased SDF-1 gene expression in fibroblasts. Also, recombinant SDF-1 and lipopolysaccharide stimulated fibroblast-conditioned medium up-regulated peripheral blood mononuclear cell mobility. In the burn patients with HTS who received subcutaneous IFNα2b treatment, increased SDF-1/CXCR4 signaling was found prior to treatment which was down-regulated after IFNα2b administration, coincident with enhanced remodeling of their HTS. Our results suggest that SDF-1/CXCR4 signaling is involved in the development of HTS by promoting migration of activated CD14+ CXCR4+ cells from the bloodstream to wound sites, where they may differentiate into fibrocyte and myofibroblasts and contribute to the development of HTS.     

Programmable cells: interfacing natural and engineered gene networks

Novel cellular behaviors and characteristics can be obtained by coupling engineered gene networks to the cell's natural regulatory circuitry through appropriately designed input and output interfaces. Here, we demonstrate how an engineered genetic circuit can be used to construct cells that respond to biological signals in a predetermined and programmable fashion. We employ a modular design strategy to create Escherichia coli strains where a genetic toggle switch is interfaced with: (i) the SOS signaling pathway responding to DNA damage, and (ii) a transgenic quorum sensing signaling pathway from Vibrio fischeri. The genetic toggle switch endows these strains with binary response dynamics and an epigenetic inheritance that supports a persistent phenotypic alteration in response to transient signals. These features are exploited to engineer cells that form biofilms in response to DNA-damaging agents and cells that activate protein synthesis when the cell population reaches a critical density. Our work represents a step toward the development of "plug-and-play" genetic circuitry that can be used to create cells with programmable behaviors.     

Left ventricular oozing rupture following acute myocardial infarction

We describe the case of an 85-year-old woman in whom pericardiocentesis, prolonged bed rest and blood pressure control were performed without surgery to successfully treat an oozing-type myocardial rupture due to myocardial infarction.