Intrathecal non-viral interleukin-10 gene therapy ameliorates neuropathic pain as measured by both classical static allodynia and a novel supra-spinally mediated pain assay, the Two-Arm Rodent Somatosensory (TARS) task

Intrathecal delivery of interleukin-10 (IL-10) gene therapy has been reported to be effective in suppressing pain enhancement in a variety of rodent models. However, all publications that have tested this treatment have relied upon measures of static allodynia (von Frey test) and thermal hyperalgesia (Hargreaves test). As this plasmid DNA IL-10 (pDNA-IL10) therapeutic approach is now in human clinical trials for multiple pain indications, including intrathecal delivery for human neuropathic pain, it is important to consider the recent concerns raised in the pain field that such tests reflect spinal rather than supraspinal processing of, and responsivity to, noxious stimuli. Consequently, this raises the question of whether intrathecal pDNA-IL10 can reverse established neuropathic pain when assessed by a test requiring supraspinal, rather than solely spinal, mediation of the behavioral response. The present study utilizes the rat sciatic chronic constriction injury (CCI) model of neuropathic pain to compare the expression of static allodynia with that of cognitively controlled choice behavior in a two-arm maze, adapted from Hayashida et al. (2019). This modification, termed the Two-Arm Rodent Somatosensory (TARS) task, provides rats free choice to reach a desired goal box via a short "arm" of the maze with tactile probes as flooring versus a longer "arm" of the maze with a smooth surface. Here we demonstrate that static allodynia and avoidance of the nociceptive flooring in TARS develop in parallel over time, and that both behaviors also resolve in parallel following intrathecal pDNA-IL10 gene therapy. Details for the construction and use of this new maze design are also provided. Together, this study documents both: (a) the important finding that intrathecal IL-10 gene therapy does indeed resolve neuropathic pain as measured by a supraspinally-mediated behavioral task, and (b) a new, supraspinally-mediated task that allows behavioral assessments across weeks and allows the analysis of both development and resolution of neuropathic pain by therapeutic interventions. As such, the TARS operant behavior task is an improvement over other approaches such as the mechanical conflict-avoidance system which have difficulties demonstrating development and reversal of pain behavior in a within-subject design.

Modifiable Host Factors for the Prevention and Treatment of COVID-19: Diet and Lifestyle/Diet and Lifestyle Factors in the Prevention of COVID-19

Many studies have shown that the immune system requires adequate nutrition to work at an optimal level. Not only do optimized nutritional strategies support the immune system, but they also reduce chronic inflammation. Nutritional supplements that are recommended for patients with critical illnesses are thought to also be effective for the coronavirus disease 2019 (COVID-19) patients in the intensive care unit. Some studies have recommended fresh fruits and vegetables, soy, nuts, and antioxidants, such as omega-3 fatty acids, to improve immune system activity. Although nutritional status is considered to be an important prognostic factor for patients with COVID-19, there is to date no sufficient evidence that optimal nutritional therapies can be beneficial for these patients. Some have argued that the COVID-19 pandemic is a good opportunity to test the effectiveness of nutritional intervention for infectious diseases. Many researchers have suggested that testing the proposed nutritional approaches for infectious diseases in the context of a pandemic would be highly informative. The authors of other review papers concluded that it is important to have a diet based on fresh foods, such as fruits, vegetables, whole grains, low-fat dairy products, and healthy fats (i.e., olive oil and fish oil), and to limit the intake of sugary drinks as well as high-calorie and high-salt foods. In this review, we discuss the clinical significance of functional food ingredients as complementary therapies potentially beneficial for the prevention or treatment of COVID-19. We believe that our review will be helpful to plan and deploy future studies to conclude these potentials against COVID-19, but also to new infectious diseases that may arise in the future.

Coreceptor Functions of Cell Surface Heparan Sulfate Proteoglycans

Receptor-ligand interactions play an important role in many biological processes by triggering specific cellular responses. These interactions are frequently regulated by coreceptors that facilitate, alter, or inhibit signaling. Coreceptors work in parallel with other specific and accessory molecules to coordinate receptor-ligand interactions. Cell surface heparan sulfate proteoglycans (HSPGs) function as unique coreceptors because they can bind to many ligands and receptors through their HS and core protein motifs. Cell surface HSPGs are typically expressed in abundance of the signaling receptors and, thus, are capable of mediating the initial binding of ligands to the cell surface. HSPG coreceptors do not possess kinase domains or intrinsic enzyme activities and, for the most part, binding to cell surface HSPGs does not directly stimulate intracellular signaling. Because of these features, cell surface HSPGs primarily function as coreceptors for many receptor-ligand interactions. Given that cell surface HSPGs are widely conserved, they likely serve fundamental functions to preserve basic physiological processes. Indeed, cell surface HSPGs can support specific cellular interactions with growth factors, morphogens, chemokines, extracellular matrix (ECM) components, and microbial pathogens and their secreted virulence factors. Through these interactions, HSPG coreceptors regulate cell adhesion, proliferation, migration and differentiation, and impact the onset, progression, and outcome of pathophysiological processes, such as development, tissue repair, inflammation, infection, and tumorigenesis. This review seeks to provide an overview of the various mechanisms of how cell surface HSPGs function as coreceptors.

Short-term effects of low-dose tolvaptan in acute decompensated heart failure patients with severe aortic stenosis: the LOHAS registry

Background

Tolvaptan exerts potent diuretic effects in heart failure patients without hemodynamic instability. Nonetheless, its clinical efficacy for acute decompensated heart failure (ADHF) due to severe aortic stenosis (AS) remains unclear. This study aimed to evaluate the short-term effects of tolvaptan in ADHF patients with severe AS.

Methods

The LOw-Dose Tolvaptan (7.5 mg) in Decompensated Heart Failure Patients with Severe Aortic Stenosis (LOHAS) registry is a multicenter (7 centers) prospective registry that assessed the short-term effects of tolvaptan in subjects hospitalized for ADHF with severe AS. A total of 59 subjects were enrolled between September 2014 and December 2017. The primary endpoints were changes in body weight and fluid balance measured daily from baseline up to 4 days.

Results

The median [interquartile range] patient age and aortic valve area were 85.0 [81.0–89.0] years and 0.58 [0.42–0.74] cm2, respectively. Body weight continuously decreased, and fluid balance was maintained from baseline to day 4 (p<0.001, p=0.194, respectively). Median serum B-type natriuretic peptide concentration significantly decreased from 910.5 to 740.0 pg/mL by day 4 (p=0.002). However, systolic blood pressure and heart rate were non-significantly changed (p=0.250, p=0.656, respectively). Hypernatremia (>150 mEq/L) and worsening renal function occurred in 2 (3.4%) and 4 (6.8%) patients, respectively.

Conclusions

Short-term treatment with low-dose tolvaptan is safe and effective, providing stable hemodynamic parameters in patients with ADHF and severe AS.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): This research was supported by Otsuka Pharmaceutical Co., Ltd.

Syndecan-1 limits the progression of liver injury and promotes liver repair in acetaminophen-induced liver injury in mice

Accidental or intentional misuse of acetaminophen (APAP) is the leading cause of acute liver failure in the Western world. Although mechanisms that trigger APAP-induced liver injury (AILI) are well known, those that halt the progression of APAP liver disease and facilitate liver recovery are less understood. Heparan sulfate proteoglycans (HSPGs) bind to and regulate various tissue injury factors through their heparan sulfate (HS) chains, but the importance of HSPGs in liver injury in vivo remains unknown. Here, we examined the role of syndecan-1, the major cell-surface HSPG of hepatocytes, in AILI. Ablation of syndecan-1 in mice led to unopposed progression of liver injury upon APAP overdose. However, direct APAP hepatoxicity and liver injury at early times post-APAP overdose were unaffected by syndecan-1, suggesting that syndecan-1 influences later mechanisms that lead to liver repair. The exuberant liver injury phenotypes in syndecan-1 null (Sdc1^-/- ) mice were traced to a deficiency in protein kinase B (Akt) activation in hepatocytes, which led to a delayed increase in glycogen synthase kinase-3β (GSK-3β)-mediated hepatocyte apoptosis. Inhibition of Akt worsened, whereas inhibition of GSK-3β and caspases protected mice from AILI. Moreover, administration of purified syndecan-1, HS, or engineered heparan compounds containing 2-O-sulfate groups rescued Sdc1^-/- mice from AILI by potentiating Akt signaling and inhibiting GSK-3β-mediated apoptosis in hepatocytes. In addition, HS showed a significantly prolonged therapeutic efficacy as compared to N-acetylcysteine.

CONCLUSION

These results demonstrate that 2-O-sulfated domains in syndecan-1 HS halt disease progression and promote liver repair by enhancing hepatocyte survival in AILI. We propose that syndecan-1 is a critical endogenous factor that controls the balance between prosurvival signaling and apoptosis in hepatocytes in APAP liver disease. (Hepatology 2017;66:1601-1615).

Venous superdrained gastric tube pull-up procedure for hypopharyngeal and cervical esophageal reconstruction reduces postoperative anastomotic leakage and stricture

Gastric pull-up is a common procedure to reconstruct the continuity of the upper digestive tract after esophageal resection. However, this technique sometimes causes postoperative anastomotic leakage or stricture, resulting from insufficient blood flow at the distal end. To overcome this problem, additional microvascular venous anastomoses were performed. The purpose of this study was to compare the outcomes of post-surgical anastomotic leakage and stricture in patients with and without additional microvascular venous superdrainage after cervical esophageal and hypopharyngeal resection and gastric tube reconstruction. A total of 29 consecutive patients with esophageal or hypopharyngeal cancer who underwent total esophagectomy and hypopharyngectomy with gastric tube reconstruction in the National Organization Nagasaki Medical Center between April 2014 and May 2016 were analyzed in this study. Of these patients, 20 underwent additional venous anastomoses (superdrainage group), and 9 did not undergo additional procedures (standard group). We compared the frequency of post-surgical stricture and leakage in the two groups retrospectively. Three of nine patients (33.3%) developed postoperative leakage in the standard group, and 1 of 20 (5.0%) did so in the superdrainage group. Six of nine patients (66.7%) showed postoperative anastomotic stricture in the standard group, but none did so in the superdrainage group. Patients who did not undergo additional venous superdrainage were significantly more likely to develop postsurgical leakage (P < 0.05, Chi-square test) and anastomotic stricture (P < 0.001, Chi-square test). Our study revealed that only additional venous anastomoses could reduce the incidence of postoperative anastomotic leakage and stricture. This procedure is of merit to perform after total esophagectomy and hypopharyngectomy with gastric tube reconstruction.

EXTL3 mutations cause skeletal dysplasia, immune deficiency, and developmental delay

Volpi et al. demonstrate that hypomorphic EXTL3 mutations cause abnormalities of heparan sulfate composition, affect signaling in response to growth factors and cytokines, and perturb thymopoiesis, resulting in a novel genetic disease associating skeletal dysplasia, T cell immunodeficiency, and neurodevelopmental delay.

We studied three patients with severe skeletal dysplasia, T cell immunodeficiency, and developmental delay. Whole-exome sequencing revealed homozygous missense mutations affecting exostosin-like 3 (EXTL3), a glycosyltransferase involved in heparan sulfate (HS) biosynthesis. Patient-derived fibroblasts showed abnormal HS composition and altered fibroblast growth factor 2 signaling, which was rescued by overexpression of wild-type EXTL3 cDNA. Interleukin-2–mediated STAT5 phosphorylation in patients’ lymphocytes was markedly reduced. Interbreeding of the extl3-mutant zebrafish (box) with Tg(rag2:green fluorescent protein) transgenic zebrafish revealed defective thymopoiesis, which was rescued by injection of wild-type human EXTL3 RNA. Targeted differentiation of patient-derived induced pluripotent stem cells showed a reduced expansion of lymphohematopoietic progenitor cells and defects of thymic epithelial progenitor cell differentiation. These data identify EXTL3 mutations as a novel cause of severe immune deficiency with skeletal dysplasia and developmental delay and underline a crucial role of HS in thymopoiesis and skeletal and brain development.

Evaluation of Acute Myocardial Infarction In-hospital Mortality Using a Risk-adjustment Model Based on Japanese Administrative Data

This study aimed to develop a new risk-adjustment method to assess acute myocardial infarction (AMI) in-hospital mortality. Risk-adjustment was based on variables obtained from administrative data from Japanese hospitals, and included factors such as age, gender, primary diagnosis and co-morbidity. The infarct location was determined using the criteria of the International Classification of Diseases (10th version). Potential co-morbidity risk factors for mortality were selected based on previous studies and their critical influence analysed to identify major co-morbidities. The remaining minor co-morbidities were then divided into two groups based on their medical implications. The major co-morbidities included shock, pneumonia, cancer and chronic renal failure. The two minor co-morbidity groups also demonstrated a substantial impact on mortality. The model was then used to assess clinical performance in the participating hospitals. Our model reliably employed the available data for the risk-adjustment of AMI mortality and provides a new approach to evaluating clinical performance.

Spinal antinociceptive effects of the novel NOP receptor agonist PWT2-nociceptin/orphanin FQ in mice and monkeys

BACKGROUND AND PURPOSE

Using an innovative chemical approach, peptide welding technology (PWT), a tetrabranched derivative of nociceptin/orphanin FQ (N/OFQ) has been generated and pharmacologically characterized. Both in vitro and in vivo PWT2-N/OFQ displayed the same pharmacological profile to the natural ligand. It was more potent and produced longer-lasting effects. The aim of the present study was to investigate the spinal effects of PWT2-N/OFQ in nociceptive and neuropathic pain models in mice and non-human primates.

EXPERIMENTAL APPROACH

Tail withdrawal assay in mice and monkeys was used as a nociceptive pain model and mechanical threshold in mice subjected to chronic constriction injury was used as a neuropathic pain model. The antinociceptive effects of spinally administered N/OFQ and PWT2-N/OFQ were assessed in these models.

KEY RESULTS

PWT2-N/OFQ mimicked the spinal antinociceptive effects of N/OFQ both in nociceptive and neuropathic pain models in mice as well as in non-human primates displaying 40-fold higher potency and a markedly prolonged duration of action. The effects of N/OFQ and PWT2-N/OFQ were sensitive to the N/OFQ receptor (NOP) antagonist SB-612111, but not to opioid receptor antagonists.

CONCLUSIONS AND IMPLICATIONS

The present study has demonstrated that PWT2-N/OFQ mimicked the antinociceptive effects of the natural peptide in rodents and non-human primates acting as a potent and longer-lasting NOP-selective agonist. More generally, PWT derivatives of biologically active peptides can be viewed as innovative pharmacological tools for investigating those conditions and states in which selective and prolonged receptor stimulation promotes beneficial effects.

Supraspinal actions of nociceptin/orphanin FQ, morphine and substance P in regulating pain and itch in non-human primates

BACKGROUND AND PURPOSE

Nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor agonists display a promising analgesic profile in preclinical studies. However, supraspinal N/OFQ produced hyperalgesia in rodents and such effects have not been addressed in primates. Thus, the aim of this study was to investigate the effects of centrally administered ligands on regulating pain and itch in non-human primates. In particular, nociceptive thresholds affected by intracisternal N/OFQ were compared with those of morphine and substance P, known to provide analgesia and mediate hyperalgesia, respectively, in humans.

EXPERIMENTAL APPROACH

Intrathecal catheters were installed to allow intracisternal and lumbar intrathecal administration in awake and unanaesthetized rhesus monkeys. Nociceptive responses were measured using the warm water tail-withdrawal assay. Itch scratching responses were scored from videotapes recording behavioural activities of monkeys in their home cages. Antagonist studies were conducted to validate the receptor mechanisms underlying intracisternally elicited behavioural responses.

KEY RESULTS

Intracisternal morphine (100 nmol) elicited more head scratches than those after intrathecal morphine. Distinct dermatomal scratching locations between the two routes suggest a corresponding activation of supraspinal and spinal μ receptors. Unlike intracisternal substance P, which induced hyperalgesia, intracisternal N/OFQ (100 nmol) produced antinociceptive effects mediated by NOP receptors. Neither peptide increased scratching responses.

CONCLUSIONS AND IMPLICATIONS

Taken together, these results demonstrated differential actions of ligands in the primate supraspinal region in regulating pain and itch. This study not only improves scientific understanding of the N/OFQ-NOP receptor system in pain processing but also supports the therapeutic potential of NOP-related ligands as analgesics.

Diagnostic performance of plasma biomarkers in patients with acute intestinal ischaemia

BACKGROUND

The aim of this study was to evaluate the use of intestinal fatty acid binding protein (I-FABP) and traditional biomarkers in the early diagnosis of acute intestinal ischaemia of different causes.

METHODS

I-FABP, white blood cell (WBC) count, C-reactive protein, base deficit, lactate, lactate dehydrogenase, aspartate aminotransferase, creatine kinase and D-dimer were measured prospectively in consecutive patients suspected of having acute intestinal ischaemia. Biomarker levels were compared in patients with vascular and non-vascular ischaemia.

RESULTS

Two hundred and eight patients with a clinical suspicion of acute intestinal ischaemia were enrolled. Vascular intestinal ischaemia was diagnosed in 24 patients (11·5 per cent), non-vascular ischaemia in 62 (29·8 per cent) and non-ischaemic disease in 122 (58·7 per cent). The levels of most biomarkers (except WBC count and creatine kinase) were significantly higher in the vascular ischaemia group than in the other groups (P < 0·010). However, none of the biomarker levels differed between patients with non-vascular intestinal ischaemia and those with non-ischaemic disease. Receiver operating characteristic (ROC) curve analysis suggested that I-FABP was best at diagnosing vascular intestinal ischaemia (area under the curve 0·88).

CONCLUSION

Serum biomarkers may be useful in the diagnosis of vascular, but not non-vascular, intestinal ischaemia. Among them, I-FABP shows promise for detecting vascular ischaemia.

The puerperium alters spinal cord plasticity following peripheral nerve injury

Tissue and nerve damage can result in chronic pain. Yet, chronic pain after cesarean delivery is remarkably rare in women and hypersensitivity from peripheral nerve injury in rats resolves rapidly if the injury occurs in the puerperium. Little is known regarding the mechanisms of this protection except for a reliance on central nervous system oxytocin signaling. Here we show that the density of inhibitory noradrenergic fibers in the spinal cord is greater when nerve injury is performed in rats during the puerperium, whereas the expression of the excitatory regulators dynorphin A and neuregulin-1 in the spinal cord is reduced. The puerperium did not alter spinal cord microgial and astrocyte activation. Astrocyte activation, as measured by glial fibrillary acidic protein (GFAP) expression, was not evident in female rats with injury, regardless of delivery status suggesting sex differences in spinal astrocyte activation after injury. These results suggest a change in the descending inhibitory/facilitating balance on spinal nociception neurotransmission during the puerperium, as mechanisms for its protective effect against injury-induced hypersensitivity.

Impact of system-level activities and reporting design on the number of incident reports for patient safety

BACKGROUND

Incident reporting is a promising tool to enhance patient safety, but few empirical studies have been conducted to identify factors that increase the number of incident reports. Objective To evaluate how the number of incident reports are related to system-level activities and reporting design.

METHODS

A questionnaire survey was administered to all 1039 teaching hospitals in Japan. Items on the survey included number of reported incidents; reporting design of incidents; and status for system-level activities, including assignment of safety managers, conferences, ward rounds by peers, and staff education. Staff education encompasses many aspects of patient safety and is not limited to incident reporting. Poisson regression models were used to determine whether these activities and design of reporting method increase incident reports filed by physicians and nurses.

RESULTS

Educational activities were significantly associated with reporting by physicians (53% increase, p<0.001) but had no significant effect on nurse-generated reports. More reports were submitted by physicians and nurses in hospitals where time involved with filing a report was short (p<0.05). The impact of online reporting was limited to a 26% increase in physicians' reports (p<0.05).

CONCLUSION

In accordance with the suggestions by previous studies that examined staff perceptions and attitudes, this study empirically demonstrated that to decrease burden to reporting and to implement staff educations may improve incident reporting.

Molecular and cellular mechanisms of ectodomain shedding

The extracellular domain of several membrane-anchored proteins is released from the cell surface as soluble proteins through a regulated proteolytic mechanism called ectodomain shedding. Cells use ectodomain shedding to actively regulate the expression and function of surface molecules, and modulate a wide variety of cellular and physiological processes. Ectodomain shedding rapidly converts membrane-associated proteins into soluble effectors and, at the same time, rapidly reduces the level of cell surface expression. For some proteins, ectodomain shedding is also a prerequisite for intramembrane proteolysis, which liberates the cytoplasmic domain of the affected molecule and associated signaling factors to regulate transcription. Ectodomain shedding is a process that is highly regulated by specific agonists, antagonists, and intracellular signaling pathways. Moreover, only about 2% of cell surface proteins are released from the surface by ectodomain shedding, indicating that cells selectively shed their protein ectodomains. This review will describe the molecular and cellular mechanisms of ectodomain shedding, and discuss its major functions in lung development and disease.

Soluble lectin-like oxidized LDL receptor-1 (sLOX-1) as a sensitive and specific biomarker for acute coronary syndrome--comparison with other biomarkers

BACKGROUND

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) appears to be involved in atherosclerotic plaque vulnerability and rupture. Circulating soluble LOX-1 (sLOX-1) levels are dramatically elevated in patients with acute coronary syndrome (ACS), and its diagnostic sensitivity and specificity is superior to high-sensitivity C-reactive protein (hs-CRP). In this study, we have compared the diagnostic value of sLOX-1 for ACS with those of troponin T (TnT) and heart-type fatty acid binding protein (H-FABP).

METHODS

One hundred and seven patients who underwent coronary angiography (CAG), including 18 ACS and 89 non-ACS patients were enrolled. Peripheral blood samples were obtained during the emergent or elective CAG. The non-ACS group consisted of 30 patients with normal CAG, 30 stable angina pectoris patients controlled by medical treatment, and 29 patients with stable angina who required elective coronary revascularization (percutaneous coronary intervention or coronary artery bypass graft).

RESULTS

Age, gender, lipid profiles, or prevalence of diabetes, smoking, or hypertension were not significantly different between ACS and non-ACS. These factors did not significantly affect blood sLOX-1 levels. Circulating sLOX-1, TnT, and H-FABP levels were significantly higher in ACS than non-ACS. Area under the curve (AUC) values of the receiver-operating characteristic curves were 0.948, 0.704, and 0.691 for sLOX-1, TnT, and H-FABP, respectively. In a TnT-negative (<0.03 ng/mL) subgroup, the AUC values for sLOX-1 and H-FABP were 0.848 and 0.476, respectively.

CONCLUSION

Circulating sLOX-1 is a more sensitive and specific biomarker for ACS than TnT and H-FABP, and provides additional diagnostic values when measured in combination with TnT.

Soluble lectin-like oxidized low-density lipoprotein receptor-1 predicts prognosis after acute coronary syndrome--a pilot study

BACKGROUND

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is implicated in atherosclerotic plaque vulnerability. It is shed, in part, by proteases and released as soluble LOX-1 (sLOX-1), which is a specific and sensitive biomarker of acute coronary syndrome (ACS). The present study explored if sLOX-1 can also predict prognosis after ACS.

METHODS AND RESULTS

ACS patients undergoing emergency percutaneous coronary intervention and measurement of circulating sLOX-1 were followed (median: 896 days). Among 94 patients, 13 had ACS recurrence or died (re-ACS/death group). None of age, sex, lipid profile or prevalence of diabetes, smoking or hypertension was significantly different between the re-ACS/death group and the event-free survival group. Circulating sLOX-1 levels, but not those of high-sensitivity C-reactive protein (hs-CRP) or troponin T (TnT), were significantly (P<0.005) higher in the re-ACS/death group than in the event-free survival group. Kaplan-Meier survival curves showed that ACS patients with sLOX-1 values in the highest quartile or tertile had more frequent and earlier ACS recurrence or death. Receiver-operating characteristic curves for prediction of re-ACS or death showed higher sensitivity and specificity for sLOX-1 (area under the curve for sLOX-1, hs-CRP and TnT: 0.764, 0.658 and 0.524, respectively).

CONCLUSIONS

Circulating sLOX-1, a diagnostic biomarker of ACS, also predicts ACS recurrence or death.

The expressions of claudin-1 and E-cadherin in junctional epithelium

BACKGROUND AND OBJECTIVE

The epithelium provides an important barrier against microbial invasion. Tight junction structural proteins called claudins are known to contribute to the epithelial cell barrier. Junctional epithelium is located at a strategically important interface between gingival sulcus and is interconnected by desmosomes and gap junctions, but not by tight junctions. Although claudins are tight junction-associated proteins, they are also expressed in the epithelium despite its lack of tight junctions in invertebrates. Therefore, claudins may play an important role in junctional epithelium without tight junctions. E-cadherin is a key molecule in the formation of adherence junctions and desmosomes. In the present study, we aimed to investigate the expressions of claudin-1,claudin-3, claudin-7 and E-cadherin in the junctional epithelium of Fischer 344 rats.

MATERIAL AND METHODS

Gingival tissues from Fischer 344 rats were analyzed by immunohistochemical staining for claudin-1, claudin-3, claudin-7, and E-cadherin.

RESULTS

Intense staining for claudin-1 and E-cadherin were observed in the junctional epithelium. In contrast to claudin-1, claudin-3 was mainly expressed in oral gingival epithelium and claudin-7 could not be detected on immunohistochemical analysis of the rat gingiva.

CONCLUSION

These data suggest that claudin-1 and E-cadherin exist in the junctional epithelium and may play an important role in epithelial barrier function.

Circulating soluble SR-PSOX/CXCL16 as a biomarker for acute coronary syndrome -comparison with high-sensitivity C-reactive protein

AIM

Diagnostic values of soluble SR-PSOX/CXCL16 (sSR-PSOX/CXCL16), a receptor for atherogenic oxidized LDL and a membrane-anchored chemokine for CXCR6-positive lymphocytes, for acute coronary syndrome (ACS) were evaluated..

METHODS

We examined 106 patients undergoing coronary angiography (CAG); 17 patients with ACS and 89 patients without ACS (non-ACS) including stable angina. Circulating sSR-SPOX/CXCL16 was measured in peripheral venous blood by sandwich ELISA.

RESULTS

Age, gender, prevalence of diabetes or hypertension, and serum lipid profiles were not significantly different between ACS and non-ACS. Presence or absence of risk factors, such as diabetes, smoking and hypertension, did not significantly affect circulating sSR-PSOX/CXCL16 levels. Circulating sSR-PSOX/CXCL16 levels were significantly lower in ACS than non-ACS (median: 3.05 versus 3.36 ng/mL, p<0.02). Lipid profiles, high-sensitivity C-reactive protein (hs-CRP), cardiac troponin T (TnT), and soluble LOX-1 (sLOX-1) showed no significant correlation with sSR-PSOX/CXCL16. Receiver-operating characteristic (ROC) curves for ACS detection indicate higher sensitivity and specificity for sSR-PSOX/CXCL16 than hs-CRP. In the TnT-negative and sLOX-1-negative subpopulation, sSR-PSOX/CXCL16 showed similar sensitivity and specificity for ACS; however, hs-CRP showed less sensitivity and specificity for ACS when compared with the whole population.

CONCLUSION

sSR-PSOX/CXCL16 is a biomarker for ACS, which would provide additional diagnostic information besides TnT and sLOX-1.

Generation of monoclonal antibodies against a soluble form of lectin-like oxidized low-density lipoprotein receptor-1 and development of a sensitive chemiluminescent enzyme immunoassay

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), expressed prominently in atherosclerotic lesions, is cleaved and released as a soluble LOX-1 (sLOX-1), which is a specific biomarker to diagnose acute coronary syndrome (ACS) at an early stage. Although sLOX-1 levels in patient's blood were successfully measured with our previously established enzyme-linked immunosorbent assay (ELISA), the assay was not sensitive enough to detect normal serum levels of sLOX-1 in healthy human subjects. We therefore developed sensitive and specific monoclonal antibodies (mAbs) against sLOX-1 in order to establish a more sensitive immunoassay. Mice were immunized with recombinant human LOX-1 extracellular domain. mAbs were subsequently generated by standard myeloma cell fusion techniques with a novel screening method using time-resolved fluorescence immunoassay. Using two anti-human sLOX-1 mAbs and alkaline phosphatase as a label, a sandwich chemiluminescent enzyme immunoassay (CLEIA) was developed. In total, nine mAbs were obtained. The dissociation constant (K(d)) values of these mAbs for sLOX-1 were 0.12-1.32 nM. Characteristics of these mAbs were estimated and the best combination for CLEIA was selected. The newly established CLEIA could determine sLOX-1 levels as low as 8 pg/mL, and thus, was sensitive enough to measure serum sLOX-1 levels in normal human subjects and to evaluate subtle differences. Values for sLOX-1 measured by monoclonal CLEIA and polyclonal ELISA were highly correlated (r(2)=0.7594, p<0.0001). Area under the curve values of the receiver-operating characteristic curves in detecting ACS were 0.948 and 0.978 for monoclonal CLEIA and polyclonal ELISA, respectively. Thus, a more sensitive sLOX-1 CLEIA was established using newly developed mAbs against sLOX-1. In addition to its advantage in early diagnosis of ACS, this assay may also be useful in predicting cardiovascular disease risk in disease-free subjects.

Syndecan-1 ectodomain shedding is regulated by the small GTPase Rab5

The ectodomain shedding of syndecan-1, a major cell surface heparan sulfate proteoglycan, modulates molecular and cellular processes central to the pathogenesis of inflammatory diseases. Syndecan-1 shedding is a highly regulated process in which outside-in signaling accelerates the proteolytic cleavage of syndecan-1 ectodomains at the cell surface. Several extracellular agonists that induce syndecan-1 shedding and metalloproteinases that cleave syndecan-1 ectodomains have been identified, but the intracellular mechanisms that regulate syndecan-1 shedding are largely unknown. Here we examined the role of the syndecan-1 cytoplasmic domain in the regulation of agonist-induced syndecan-1 shedding. Our results showed that the syndecan-1 cytoplasmic domain is essential because mutation of invariant cytoplasmic Tyr residues abrogates ectodomain shedding, but not because it is Tyr phosphorylated upon shedding stimulation. Instead, our data showed that the syndecan-1 cytoplasmic domain binds to Rab5, a small GTPase that regulates intracellular trafficking and signaling events, and this interaction controls the onset of syndecan-1 shedding. Syndecan-1 cytoplasmic domain bound specifically to Rab5 and preferentially to inactive GDP-Rab5 over active GTP-Rab5, and shedding stimulation induced the dissociation of Rab5 from the syndecan-1 cytoplasmic domain. Moreover, the expression of dominant-negative Rab5, unable to exchange GDP for GTP, interfered with the agonist-induced dissociation of Rab5 from the syndecan-1 cytoplasmic domain and significantly inhibited syndecan-1 shedding induced by several distinct agonists. Based on these data, we propose that Rab5 is a critical regulator of syndecan-1 shedding that serves as an on-off molecular switch through its alternation between the GDP-bound and GTP-bound forms.

Syndecan-1 is an in vivo suppressor of Gram-positive toxic shock

Heparan sulfate proteoglycans bind to and regulate many inflammatory mediators in vitro, suggesting that they serve an important role in influencing inflammatory responses in vivo. Here we evaluated the role of syndecan-1, a major heparan sulfate proteoglycan, in modulating inflammatory responses in Gram-positive toxic shock, a systemic disease that is a significant cause of morbidity and mortality. Syndecan-1-null and wild-type mice were injected intraperitoneally with staphylococcal enterotoxin B, a pyrogenic superantigen, and their inflammatory responses were assessed. Syndecan-1-null mice showed significantly increased liver injury, vascular permeability, and death in response to staphylococcal enterotoxin B challenge compared with wild-type mice. Although serum levels of systemic IL-2 and IFNgamma were similar between the two backgrounds, those of TNFalpha and IL-6 were significantly increased in syndecan-1-null mice undergoing Gram-positive toxic shock. Furthermore, syndecan-1-null mice challenged with staphylococcal enterotoxin B showed enhanced T cell accumulation in tissues, whereas immunodepletion of T cells protected syndecan-1-null mice from the magnified systemic cytokine storm, inflammatory tissue injury, and death. Importantly, syndecan-1 shedding was induced in wild-type mice injected with staphylococcal enterotoxin B, and the administration of heparan sulfate, but not syndecan-1 core protein, rescued syndecan-1-null mice from lethal toxic shock by suppressing the production of TNFalpha and IL-6, and attenuating inflammatory tissue injury. Altogether, these data suggest that syndecan-1 shedding is a key endogenous mechanism that protects the host from Gram-positive toxic shock by inhibiting the dysregulation and amplification of the inflammatory response.

Cost of open versus laparoscopic appendectomy

AIMS

There are several literatures on outcome variations between patients treated with an open appendectomy (OA) and a laparoscopic appendectomy (LA). However, there are no studies assessing differences in cost and outcome that adjust for age and hospital function or region. This study examines the differences in cost and procedure-related complications of OA and LA procedures.

MATERIALS AND METHODS

This study contains 1703 appendectomy patients treated for appendicitis in 76 academic hospitals and 80 community hospitals. Demographic variables, clinical variables, length of stay (LOS), total charges (TC; US$) and complication rates were analyzed for both OA and LA procedures. The specific contributions of LA to LOS, TC, and complication rate were identified using multivariate analysis.

RESULTS

1469 (86.3%) patients underwent OA and 234 (13.7%) underwent LA. Complicated appendicitis was diagnosed in 13.1% of OA cases and 15.4% of LA cases. The complication rates were 3.4% in OA and 2.6% in LA (p=0.504). There were significant differences in LOS and TC by severity of appendicitis and by procedure type. After risk adjustment for the other study variables, LA was associated with a higher TC than OA ($1458, p0.001). However there were no significant differences in LOS or complication rates between the two treatment groups.

CONCLUSIONS

This study suggests that LA increases cost, but has no significant impact on LOS or complication rates. However, other outcomes such as quality of life or subgroup analysis for obese patients are needed for a more complete economic analysis of OA and LA.

Interleukin 18 stimulates release of soluble lectin-like oxidized LDL receptor-1 (sLOX-1)

Lectin-like oxidized LDL receptor-1 (LOX-1) appears to play crucial roles in atherosclerotic plaque rupture. We previously reported that circulating soluble LOX-1 (sLOX-1) levels are elevated in acute coronary syndrome (ACS) and that sLOX-1 can be a specific and sensitive biomarker for ACS. A proinflammatory cytokine interleukin 18 (IL-18) and its receptor are prominently expressed in atherosclerotic plaques. In addition, circulating IL-18 levels were reported to be high in ACS. In this study, we have examined if IL-18 can stimulate shedding of LOX-1 and subsequent release of sLOX-1. After transfection with LOX-1 cDNA, HEK-293T cells were incubated with or without IL-18. Cell-conditioned media and total cell lysates were subjected to immunoblot analyses with an anti-LOX-1 monoclonal antibody. In addition, ADAM10 cDNA, ADAM10 siRNA or control vector were also co-transfected into HEK-293T cells, and the cell-conditioned media and total cell lysates were subjected to LOX-1 immunoblotting after treatment with or without IL-18. The cell-conditioned medium/total cell lysate ratios in the amounts of LOX-1 or sLOX-1 were determined as sLOX-1 cleavage ratios. IL-18 (10-100ng/mL) stimulation increased the sLOX-1 cleavage by 3-4-fold in a concentration- and time-dependent manner. ADAM10 overexpression alone similarly enhanced the sLOX-1 cleavage. ADAM10 inhibition by ADAM10 siRNA transfection significantly suppressed IL-18-induced sLOX-1 cleavage. IL-18 similarly enhanced sLOX-1 cleavage in TNF-alpha-activated cultured endothelial cells, as well as LOX-1 transgenic mice in vivo. IL-18 appears one of the stimuli that enhance sLOX-1 release in ACS and ADAM10 may be involved in this process.

Molecular and cellular mechanisms of syndecans in tissue injury and inflammation

The syndecan family of heparan sulfate proteoglycans is expressed on the surface of all adherent cells. Syndecans interact with a wide variety of molecules, including growth factors, cytokines, proteinases, adhesion receptors and extracellular matrix components, through their heparan sulfate chains. Recent studies indicate that these interactions not only regulate key events in development and homeostasis, but also key mechanisms of the host inflammatory response. This review will focus on the molecular and cellular aspects of how syndecans modulate tissue injury and inflammation, and how syndecans affect the outcome of inflammatory diseases in vivo.

Preliminary application and evaluation of loop-mediated isothermal amplification (LAMP) for detection of bovine theileriosis and trypanosomosis in Tanzania : research communication

The sensitivity of LAMP, PCR and microscopy to detect Theileria spp. and Trypanosoma congolense in field-derived bovine blood samples from Tanzania was evaluated and compared. No parasites were detected by microscopy. Furthermore, no bovine Theileria spp. were detected by LAMP and PCR from all the 24 samples collected from Arusha. Four and one out of 24 samples were positive for Theileria congolense infection by LAMP and PCR respectively while, 18 and nine out of 40 samples from Dar es Salaam were positive by LAMP and PCR for Theileria spp. Infection, respectively. Although all samples from Dar es Salaam were negative for Trypanosoma congolense infections by PCR, 12 out of 40 samples were LAMP positive. Whilst PCR is an established gene amplification method for the detection of Theileria and trypanosome parasites, this study introduces LAMP as an alternative molecular diagnostic tool that could be used in large-scale epidemiological surveys.

Human peripheral blood dendritic cells and monocyte subsets display similar chemokine receptor expression profiles with differential migratory responses

Human antigen presenting cells (APC) found in peripheral blood are considered to be precursors that have been released from the bone marrow and are in transit to the peripheral tissues. These APC populations include myeloid dendritic cells (mDC), plasmacytoid DC (pDC) and monocytes (Mo). To assign specialized functional roles and stages of development for APCs, CD33 expressing APC subsets were examined for their capacity to respond to chemokines. Three major CD33(+) subsets including CD33(bright)CD14(bright) Mo, CD33(bright)CD14(-) CD11c(+) mDC and CD33(dim)CD14(-) pDC were present. Dendritic cells subsets and Mo expressed low levels of CC and CXC receptors, but distinctive chemokine receptor expression profiles were not observed. The percentage of cells expressing a particular chemokine receptor varied from donor to donor and over time in the same donor. Myeloid DC and Mo but not pDC migrated toward CXCL12 in a concentration dependent manner. Monocytes and pDC, but not myeloid DC, were attracted by high concentrations of CXCL10. All CD33(+) subsets migrated in a concentration dependent manner toward CCL19, but responded less robustly to CCL21. CCL20 was not chemoattractant for any population. Despite the finding that APC did not exhibit unique surface chemokine receptor expression patterns, they exhibited differential migration to CXCL12, CXCL10 and CCL21 but not to CCL20 or CCL19.

Mulberry leaf aqueous fractions inhibit TNF-α-induced nuclear factor κB (NF-κB) activation and lectin-like oxidized LDL receptor-1 (LOX-1) expression in vascular endothelial cells

Mulberry (Morus Alba L., family Moraceae) leaf extracts have various biological effects including inhibition of oxidative modification of low-density lipoprotein (LDL), which is the major cause of atherosclerosis. Endothelial dysfunction elicited by oxidized LDL (Ox-LDL) has been implicated in atherogenesis. Lectin-like Ox-LDL receptor-1 (LOX-1), a cell-surface receptor for atherogenic Ox-LDL, appears to mediate Ox-LDL-induced inflammation, which may be crucial in atherogenesis. Previous studies revealed that expression of LOX-1 is highly inducible by proinflammatory stimuli, including tumor necrosis factor-alpha (TNF-alpha), lipopolysaccharide (LPS), and transforming growth factor-beta (TGF-beta). Therefore, we examined whether mulberry leaf aqueous fractions inhibit LOX-1 expression induced by proinflammatory stimuli. Pretreatment of cultured bovine aortic endothelial cells (BAECs) with mulberry leaf aqueous fractions inhibited TNF-alpha- and LPS-induced expression of LOX-1 at both protein and mRNA levels in a time- and concentration-dependent manner. In contrast, mulberry leaf aqueous fractions did not affect TGF-beta-induced LOX-1 expression. Furthermore, mulberry leaf aqueous fractions inhibited TNF-alpha-induced activation of nuclear factor-kappaB (NF-kappaB) and phosphorylation of inhibitory factor of NF-kappaB-alpha (IkappaB-alpha) in a time- and concentration-dependent fashion. Thus, mulberry leaf aqueous fractions suppress TNF-alpha- and LPS-induced LOX-1 gene expression, by inhibiting NF-kappaB activation.