Tachycardia and Acute Kidney Injury among Critically Ill Patients with Sepsis: A Prospective Observational Study.

INTRODUCTION: Tachycardia caused by sympathetic overactivity impairs myocardial function and raises septic patients' mortality. This study examined whether tachycardia is associated with acute kidney injury (AKI) period-prevalence among critically ill patients with and without sepsis. METHODS: In 328 patients (119 sepsis and 209 non-sepsis) admitted to our intensive care unit (ICU), we assessed heart rate at ICU admission, plasma neutrophil gelatinase-associated lipocalin (NGAL) and N-terminal pro-B-type natriuretic peptide, and urinary L-type fatty acid-binding protein and N-acetyl-ß-d-glucosaminidase (NAG) at 0 and 48 h after admission. Tachycardia was defined as a heart rate above 100 beats/min. RESULTS: Tachycardia was independently correlated with AKI prevalence during the first week after ICU admission in the septic patients, but not in the non-septic patients. A dose-dependent increase in AKI period-prevalence was observed across ascending heart rate ranges. Furthermore, we discovered a dose-dependent increase in renal biomarker-positive patients regarding plasma NGAL and urinary NAG over increasing heart rate ranges 48 h after admission. CONCLUSION: The findings revealed an independent relationship between tachycardia and AKI prevalence during the first week of ICU in septic patients. Heart rate was found to have a dose-dependent effect on AKI prevalence and renal insult monitored by biomarkers.

Selective blockade of transient receptor potential vanilloid 4 reduces cyclophosphamide-induced bladder pain in mice.

Transient receptor potential vanilloid 4 (TRPV4) is a non-selective cation channel activated by various physical stimuli such as cell swelling and shear stress. TRPV4 is expressed in bladder sensory nerves and epithelium, and its activation produces urinary dysfunction in rodents. However, there have been few reports regarding its involvement in bladder pain. Therefore, we investigated whether TRPV4 is involved in bladder pain in mouse cystitis model. Intraperitoneal injection of cyclophosphamide (CYP; 300 mg/kg) produced mechanical hypersensitivity in the lower abdomen associated with a severe inflammatory bladder in mice. The mechanical threshold was reversed significantly in Trpv4-knockout (KO) mice. Repeated injections of CYP (150 mg/kg) daily for 4 days provoked mild bladder inflammation and persistent mechanical hypersensitivity in mice. Trpv4-KO mice prevented a reduction of the mechanical threshold without an alteration in bladder inflammation. A selective TRPV4 antagonist also reversed the mechanical threshold in chronic cystitis mice. Although expression of Trpv4 was unchanged in the bladders of chronic cystitis mice, the level of phosphorylated TRPV4 was increased significantly. These results suggest involvement of TRPV4 in bladder pain of cystitis mice. A TRPV4 antagonist might be useful for patients with irritable bladder pain such as those with interstitial cystitis/painful bladder syndrome.

Granulomatous pyoderma gangrenosum in a patient with ulcerative colitis.

A 34-year-old woman with a past history of inflammatory bowel disease developed a painful elevated edematous swelling with ulcerations on the dorsum of her left foot. Histopathological examination revealed dense infiltration of neutrophils and mononuclear cells in the lower dermis and subcutaneous tissue. Tumor necrosis factor (TNF) was strongly detected in giant cells. To date, only a few cases of pyoderma gangrenosum with granulomatous changes have been reported. Tumor necrosis factor may have played a role in the granulomatous reaction in our case.

Interface design dividing physical findings into medical and trauma findings facilitates clinical document entry in the emergency department: A prospective observational study.

PURPOSE: The interface design and its effect on workflow are key determinants of the usability of electronic medical records (EMRs) in the emergency department (ED). However, whether the overall clinical care can be improved by dividing the interface design of physical findings into medical and trauma findings is unknown. We previously developed an EMR system in which the checkpoints were separated into different sections according to the body part. Herein, we modified this EMR system by remaking the interface design specifically for trauma patients, and evaluated its performance. METHODS: This study was undertaken in a single-center ED between October 2014 and September 2015. In the modified EMR system, all trauma findings are displayed together on the screen, according to the Japan Advanced Trauma Evaluation and Care. We compared the time to final documentation entry and the length of ED stay between the previous (used in the first 6 months) and current systems (used in the latter 6 months). Furthermore, we stratified the patients by triage levels. RESULTS: The study involved 2141 patients (934 and 1207 assessed using the previous and modified EMR systems, respectively). The modified EMR in trauma patients significantly decreased the time to final documentation entry from 131.5 [interquartile range, 86.8-207.3] to 115 [78.8-161] min (p = 0.049). When stratifying trauma patients by triage level, significantly shorter clinical documentation times were observed with the modified EMR system in levels 2 (emergency) and 3 (urgent). CONCLUSIONS: Using different interfaces for trauma findings shortened the time for clinical documentation for trauma patients.

Retinoic acid regulates cell-shape and -death of E-FABP (FABP5)-immunoreactive septoclasts in the growth plate cartilage of mice.

Septoclasts, which are mononuclear and spindle-shaped cells with many processes, have been considered to resorb the transverse septa of the growth plate (GP) cartilage at the chondro-osseous junction (COJ). We previously reported the expression of epidermal-type fatty acid-binding protein (E-FABP, FABP5) and localization of peroxisome proliferator-activated receptor (PPAR)ß/δ, which mediates the cell survival or proliferation, in septoclasts. On the other hand, retinoic acid (RA) can bind to E-FABP and is stored abundantly in the GP cartilage. From these information, it is possible to hypothesize that RA in the GP is incorporated into septoclasts during the cartilage resorption and regulates the growth and/or death of septoclasts. To clarify the mechanism of the cartilage resorption induced by RA, we administered an overdose of RA or its precursor vitamin A (VA)-deficient diet to young mice. In mice of both RA excess and VA deficiency, septoclasts decreased in the number and cell size in association with shorter and lesser processes than those in normal mice, suggesting a substantial suppression of resorption by septoclasts in the GP cartilage. Lack of PPARß/δ-expression, TUNEL reaction, RA receptor (RAR)ß, and cellular retinoic acid-binding protein (CRABP)-II were induced in E-FABP-positive septoclasts under RA excess, suggesting the growth arrest/cell-death of septoclasts, whereas cartilage-derived retinoic acid-sensitive protein (CD-RAP) inducing the cell growth arrest or morphological changes was induced in septoclasts under VA deficiency. These results support and do not conflict with our hypothesis, suggesting that endogenous RA in the GP is possibly incorporated in septoclasts and utilized to regulate the activity of septoclasts resorbing the GP cartilage.

Synthesis, localization and possible function of serine (or cysteine) peptidase inhibitor, clade B, member 6a (Serpinb6a) in mouse submandibular gland.

The granular convoluted tubule (GCT) in the duct system of the submandibular gland (SMG) develops preferentially in male mice and produces a number of bioactive peptides including proteases such as renin and kallikrein. We examine the synthesis and localization of the serine (or cysteine) peptidase inhibitor, clade B, member 6a (Serpinb6a), the mouse ortholog of the human intracellular serine protease inhibitor SERPINB6, in the mouse SMG by using reverse transcription plus the polymerase chain reaction, in situ hybridization, immunoblotting and immunohistochemistry. Serpinb6a mRNA expression was more abundant in the male than in the female SMG and in the GCT than in other duct portions or acini. Within GCT cells, immunoreactivity for Serpinb6a was localized in the nucleus and cytosol but was absent in the secretory granules. The binding target of Serpinb6a in the SMG was investigated by using a mass spectrometric analysis of immunoprecipitation products and kallikrein-1-related peptidase b26 (Klk1b26), a serine protease, was identified. These results raise the possibility that Serpinb6a functions in the protection of GCT cells from intracellular kallikreins that may leak from secretory granules.

Expression and localization of calpain 3 in the submandibular gland of mice.

OBJECTIVES: Calpains comprise a family of intracellular Ca2+-dependent cysteine proteases and are considered to play roles in various physiological phenomena with limited proteolytic activities against specific substrates. We herein revealed the expression and localization of calpain 3, the muscle-type calpain, in the submandibular gland (SMG) of mice. DESIGN: The expression of the mRNA for conventional, ubiquitous calpains 1 and 2 and skeletal muscle-specific calpain 3 was examined in the major salivary glands of mice using RT-PCR, and the expression and localization of calpain 3 protein was examined in the SMG of mice using immunohistochemistry and Western blotting. RESULTS: The large catalytic subunits of calpains 1 and 2 and the small regulatory subunit common to calpains 1 and 2 were weakly expressed in the parotid gland, sublingual gland, and SMG at similar levels in males and females. In contrast, the single large catalytic subunit of calpain 3 was expressed predominantly in the SMG at markedly higher levels in males than in females and in a manner dependent on androgens. Immunoreactivity for calpain 3 was mainly localized in cells of the granular convoluted tubules (GCT) that developed preferentially in the male SMG. In GCT cells, calpain 3 immunoreactivity was localized predominantly in the cytosolic region and was absent in the secretory granules. CONCLUSIONS: These results revealed that the GCT is the primary site of production of calpain 3 in the mouse SMG.

Immunohistochemical localization of keratin 5 in the submandibular gland in adult and postnatal developing mice.

Keratin 5 (K5) is a marker of basal progenitor cells in the epithelia of a number of organs. During prenatal development of the submandibular gland (SMG) in mice, K5(+) progenitor cells in the developing epithelia play important roles in its organogenesis. Although K5(+) cells are also present in the adult mouse SMG and may function in tissue regeneration, their histological localization has not yet investigated in detail. In the present study, we examined the immunohistochemical localization of K5 in the SMG in adult and postnatal developing mice. At birth, K5 immunoreactivity was detected in the entire duct system, in which it was localized in the basal cells of a double-layered epithelium, but was not detected in the terminal tubule or myoepithelial cells. At postnatal weeks 1-3, with the development of intercalated ducts (ID), striated ducts (SD), and excretory ducts (ED), K5-immunoreactive basal cells were gradually restricted to the ED and the proximal double-layered portions of the ID connecting to the SD. At the same time, K5 immunoreactivity appeared in myoepithelial cells, in which its positive ratio gradually increased. In adults, K5 immunoreactivity was localized to most myoepithelial cells, most basal cells in the ED, and a small number of ID cells at the boundary between the ID and SD in the female SMG or between the ID and granular convoluted tubules in the male SMG. These results suggest that K5 is a marker of differentiated myoepithelial cells and duct progenitor cells in the mouse SMG.

Effects of Radiation on Spinal Dura Mater and Surrounding Tissue in Mice.

PURPOSE: Spinal surgery in a previously irradiated field carries increased risk of perioperative complications, such as delayed wound healing or wound infection. In addition, adhesion around the dura mater is often observed clinically. Therefore, similar to radiation-induced fibrosis--a major late-stage radiation injury in other tissue--epidural fibrosis is anticipated to occur after spinal radiation. In this study, we performed histopathologic assessment of postirradiation changes in the spinal dura mater and peridural tissue in mice. MATERIALS AND METHODS: The thoracolumbar transition of ddY mice was irradiated with a single dose of 10 or 20 Gy. After resection of the irradiated spine, occurrence of epidural fibrosis and expression of transforming growth factor beta 1 in the spinal dura mater were evaluated. In addition, microstructures in the spinal dura mater and peridural tissue were assessed using an electron microscope. RESULTS: In the 20-Gy irradiated mice, epidural fibrosis first occurred around 12 weeks postirradiation, and was observed in all cases from 16 weeks postirradiation. In contrast, epidural fibrosis was not observed in the nonirradiated mice. Compared with the nonirradiated mice, the 10- and 20-Gy irradiated mice had significantly more overexpression of transforming growth factor beta 1 at 1 week postirradiation and in the late stages after irradiation. In microstructural assessment, the arachnoid barrier cell layer was thinned at 12 and 24 weeks postirradiation compared with that in the nonirradiated mice. CONCLUSION: In mice, spinal epidural fibrosis develops in the late stages after high-dose irradiation, and overexpression of transforming growth factor beta 1 occurs in a manner similar to that seen in radiation-induced fibrosis in other tissue. Additionally, thinning of the arachnoid barrier cell layer was observed in the late stages after irradiation. Thus, consideration should be given to the possibility that these phenomena can occur as radiation-induced injuries of the spine.

Expression of epidermal fatty acid binding protein (E-FABP) in septoclasts in the growth plate cartilage of mice.

n-3 Polyunsaturated fatty acids play a role in regulating the growth of the long bones. Fatty acid-binding proteins (FABPs) bind and transport hydrophobic long-chain fatty acids intracellularly, and epidermal-type FABP (E-FABP) has an affinity for n-3 fatty acids. This study aimed to clarify the localization of E-FABP in the growth plate of the mouse tibia. At the chondro-osseous junction (COJ) of the growth plate, E-FABP-immunoreactivity was exclusively localized in mononuclear, spindle-shaped cells with several long processes. These E-FABP-immunoreactive cells were identified as being septoclasts, i.e., cells that resorb uncalcified transverse septa. The processes of these immunoreactive septoclasts terminated between the longitudinal and transverse septa. E-FABP-immunoreactivity was found in the entire cytoplasm and on the mitochondrial outer membrane. In ontogeny, immunoreactive septoclasts were observed immediately after emergence of the primary ossifying center and were distributed not only at the COJ but also in the metaphysis near the COJ. The number of septoclasts increased at the postnatal age of 1 week (P1w)-P2w, and thereafter gradually decreased; and the cells became concentrated at the COJ after P3w-P4w. The immunoreactivity for peroxisome proliferator-activated receptor (PPAR)ß/δ was detected in these E-FABP-immunoreactive septoclasts. The present results suggest that fatty acids, preferably n-3 ones, are intracellularly transported by E-FABP to various targets, including mitochondria and nucleus, in which PPARß/δ may play functional roles in the transcriptional regulation of genes involved in the endochondral ossification.

Proteasome dysfunction mediates obesity-induced endoplasmic reticulum stress and insulin resistance in the liver.

Chronic endoplasmic reticulum (ER) stress is a major contributor to obesity-induced insulin resistance in the liver. However, the molecular link between obesity and ER stress remains to be identified. Proteasomes are important multicatalytic enzyme complexes that degrade misfolded and oxidized proteins. Here, we report that both mouse models of obesity and diabetes and proteasome activator (PA)28-null mice showed 30-40% reduction in proteasome activity and accumulation of polyubiquitinated proteins in the liver. PA28-null mice also showed hepatic steatosis, decreased hepatic insulin signaling, and increased hepatic glucose production. The link between proteasome dysfunction and hepatic insulin resistance involves ER stress leading to hyperactivation of c-Jun NH2-terminal kinase in the liver. Administration of a chemical chaperone, phenylbutyric acid (PBA), partially rescued the phenotypes of PA28-null mice. To confirm part of the results obtained from in vivo experiments, we pretreated rat hepatoma-derived H4IIEC3 cells with bortezomib, a selective inhibitor of the 26S proteasome. Bortezomib causes ER stress and insulin resistance in vitro--responses that are partly blocked by PBA. Taken together, our data suggest that proteasome dysfunction mediates obesity-induced ER stress, leading to insulin resistance in the liver.