Defining a Role for G-Protein Coupled Receptor/cAMP/CRE-Binding Protein Signaling in Hair Follicle Stem Cell Activation

Manipulation of adrenergic signaling has been shown experimentally and clinically to affect hair follicle growth. In this study, we provide direct evidence that canonical cAMP/CRE-binding protein signaling through adrenergic receptors can regulate hair follicle stem cell (HFSC) activation and hair cycle. We found that CRE-binding protein activation is regulated through the hair cycle and coincides with HFSC activation. Both isoproterenol and procaterol, agonists of adrenergic receptors, show the capacity to activate the hair cycle in mice. Furthermore, deletion of ADRB2 receptor, which is thought to mediate sympathetic nervous system regulation of HFSCs, was sufficient to block HFSC activation. Downstream, stimulation of adenylyl cyclase with forskolin or inhibition of phosphodiesterase to increase cAMP accumulation or direct application of cAMP was each sufficient to promote HFSC activation and accelerate initiation of hair cycle. Genetic induction of a Designer Receptors Exclusively Activated by Designer Drug allele showed that G-protein coupled receptor/GαS stimulation, specifically in HFSCs, promoted the activation of the hair cycle. Finally, we provide evidence that G-protein coupled receptor/CRE-binding protein signaling can potentially act on HFSCs by promoting glycolytic metabolism, which was previously shown to stimulate HFSC activation. Together, these data provide mechanistic insights into the role of sympathetic innervation on HFSC function.

Assessment of the efficacy of intra-articular platelet rich plasma treatment in an ACLT experimental model by dynamic contrast enhancement MRI of knee subchondral bone marrow and MRI T2∗ measurement of articular cartilage

OBJECTIVE

The vascularization of subchondral bone plays a significant role in the progression of knee osteoarthritis (OA). Treatment with platelet-rich plasma (PRP) has positive effects on cartilage lesions. However, PRP's efficacy for subchondral bone marrow lesions and the relationship of these lesions to cartilage are still undiscovered. Therefore, our aims were first to longitudinally investigate the change in subchondral flow by dynamic contrast enhanced MRI and degeneration of cartilage by MRI T2∗ in an anterior cruciate transection rodent (ACLT) model, and second to examine changes in parameters after intra-articular PRP injection.

DESIGN

A 32-week investigation in 18 rats allocated to sham-control, ACLT with normal saline injection (ACLT + NS), and ACLT with PRP injection groups ended with histological evaluation. Another rat was used as a donor of allogenic PRP.

RESULTS

Compared to the sham-control group, the ACLT + NS group had higher subchondral blood volume A (0.051, 95% confidence interval: 0.009, 0.092) and lower venous washout kel (-0.030: -0.055, -0.005) from week 4; lower permeability kep from week 18 (-0.954: -1.339, -0.569); higher cartilage T2∗ values (1.803: 1.504, 2.102) reflecting collagen loss beginning at week 10. For the PRP treatment group, subchondral bone marrow A and cartilage T2∗ decreased from week 10. Histological results confirmed and were correlated with the MRI findings.

CONCLUSION

Subchondral hyper-perfusion plays a vital role in the pathogenesis of OA and was associated with cartilage degeneration. The efficacy of PRP can be observed from reduced perfusion and MRI T2∗ values.

Risk of post-contrast acute kidney injury in emergency department patients with sepsis

INTRODUCTION

Although computed tomography (CT) is a useful tool for exploring occult infection in patients with sepsis in the emergency department, the potential nephrotoxicity of contrast media is a major concern. Our study aimed to investigate the association between use of contrast-enhanced CT and the risks of acute kidney injury and other adverse outcomes in patients with sepsis.

METHODS

In total, 587 patients with sepsis who underwent CT scan (enhanced CT group: 105, non-enhanced CT group: 482) from January 2012 to December 2016 at a tertiary referral centre were enrolled in this retrospective analysis, and propensity score matching was performed to minimise the selection bias. The length of stay, incidences of acute kidney injury and emergent dialysis, and short-term mortality were compared between the two groups.

RESULTS

Compared with patients in the non-enhanced CT group, patients in the contrast-enhanced CT group did not have increased risks of acute kidney injury (odds ratio [OR]=1.38, 95% confidence interval [CI]=0.55-3.43; P=0.489), emergent dialysis (OR=1.31, 95% CI=0.47-3.68; P=0.602), or short-term mortality (OR=0.90, 95% CI=0.48-1.69; P=0.751). In addition, there was no significant difference in the median length of hospital stay between survivors in the two groups (20 vs 19 days, P=0.742).

CONCLUSIONS

Intravenous contrast administration during CT scanning was not associated with prolonged length of hospital stay in patients with sepsis in an emergency setting. Moreover, the use of contrast-enhanced CT was not associated with increased risks of acute kidney injury, emergent dialysis, or short-term mortality.

P5388N-cadherin promotes cardiac regeneration by stabilizing beta-catenin

Background

Although the adult mammalian heart fails to regenerate after injury, it is known that newborn mice within a week have full cardiac regenerative capacity. The molecular determinants underlying the disparate regenerative capacity between neonatal and adult mice, however, remain incompletely understood. Exploiting RNA sequencing in isolated cardiomyocytes from neonatal and adult mouse heart, we identified Cdh2, which encodes the adherence junction protein N-cadherin, as a potential novel mediator of cardiac regeneration. Cdh2 expression levels were much higher in neonatal, compared with adult, cardiomyocytes and showed a strong positive correlation with that of multiple cell cycle genes. N-cadherin has been reported to be essential for embryonic cardiac development; its role in cardiac regeneration, however, remains unknown.

Purpose

To determine the role of Cdh2 (N-cadherin) in cardiac regeneration and to investigate the underlying molecular mechanisms.

Methods

Apical resection in postnatal day 1 mice was used as a cardiac regenerative model. The in vitro gain/loss-of function studies of Cdh2/N-cadherin was performed in postnatal day 1 neonatal mouse cardiomyocytes (P1CM) and human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM). N-cadherin inhibitor exherin was used to study the effects of N-cadherin in vivo.

Results

Comparing to sham-operated control, Cdh2 was significantly upregulated in mouse cardiac apex and border zone following apical resection, which was accompanied with increased cardiomyocyte proliferation activity. In vitro, knocking down Cdh2 or inhibition of N-cadherin activity with exherin in P1CM significantly reduced the proliferative activity of cardiomyocytes, whereas overexpression of Cdh2 markedly increased the proliferation of P1CM. In addition, forced expression of Cdh2 resulted in significant upregulation of multiple cell cycle genes, including Ccnd1 (Cyclin D1) and Pcna (proliferating cell nuclear antigen), in P1CM. In vivo inhibition of N-cadherin in P1 neonatal mice with exherin following apical resection impaired cardiac regeneration and increased scar formation (Figure). Knocking down CDH2 in human iPSC-CMs significantly reduced the proliferative activity and the expression levels of cell cycle gene CCND1 in iPSC-CMs. Mechanistically, we demonstrated that the pro-mitotic effects of N-cadherin in cardiomyocytes were mediated, at least partially, by stabilizing β-catenin, a pro-mitotic transcription factor, through direct interaction with its cytoplasmic domain and/or inactivation of GSK3β, a critical component of β-catenin destruction complex.

N-Cad blocker impairs heart regeneration

Conclusion

Our study uncovered a previously unrecognized role of Cdh2 (N-cadherin) in cardiomyocyte proliferation and cardiac regeneration. Enhancing cardiac expression or activity of N-cadherin, therefore, could be a potential novel therapeutic approach to promote cardiac regeneration and restore cardiac function in adult heart following injury.

The incidence and predictors of HBV relapse after cessation of tenofovir therapy in chronic hepatitis B patients

This study investigates the incidences and predictors of hepatitis B virus (HBV) relapse after tenofovir disoproxil fumarate (TDF) therapy in hepatitis B e antigen (HBeAg)-positive and -negative patients. We retrospectively recruited 143 chronic hepatitis B (CHB) patients without cirrhosis (39 HBeAg-positive and 104 HBeAg-negative patients) who were previously treated with TDF and had post-treatment follow-up for at least 6 months (median: 55, IQR 36-85 weeks). All the patients fulfilled the stopping criteria of APASL 2012. The virological and clinical relapse rates at 104 weeks in HBeAg-positive patients were 66.6% and 59.1%, while they were 72.3% and 55.9%, respectively, in HBeAg-negative patients. Cox regression analysis revealed that the higher end-of-treatment HBsAg levels were an independent factor of virological relapse in HBeAg-positive and HBeAg-negative patients. The end-of-treatment HBsAg levels of 200 (area under the receiver operating characteristic (AUROC): 0.624) and 80 IU/mL (AUROC: 0.959) were the optimal values for predicting HBV relapse in HBeAg-positive and HBeAg-negative patients, respectively. The virological relapse rate at 78 weeks was 14.3% and 19.6% in HBeAg-positive and HBeAg-negative patients who achieved HBsAg ≤200 IU/mL and HBsAg ≤80 IU/mL, respectively. Two patients experienced hepatic decompensation upon hepatitis flares, and no patient died after timely retreatment. Seven patients experienced off-therapy HBsAg loss. The cumulative rates of HBsAg loss at 104 weeks were 45.5% and 59.3% in patients with end-of-treatment HBsAg ≤80 IU/mL and ≤50 IU/mL, respectively. In conclusions, the end-of-treatment HBsAg levels were a useful marker for predicting HBV relapse in HBeAg-positive and HBeAg-negative CHB patients.

What happens after no contralateral exploration in total extraperitoneal (TEP) herniorrhaphy of clinical unilateral inguinal hernias?

BACKGROUND

While performing unilateral TEP herniorrhaphy, controversy still exists about whether to do contralateral exploration or not. Routine contralateral exploration has been proposed to prevent metachronous contralateral hernias by the repair of incidental contralateral occult hernias. Some surgeons have even proposed to do prophylactic bilateral TEP herniorrhaphy for unilateral hernia patients. To evaluate the appropriateness of not doing contralateral exploration in unilateral TEP herniorrhaphy, we reviewed our experiences under our practice of no contralateral exploration and we also reviewed other published literature.

METHODS

A total of 305 patients who underwent 313 TEP herniorrhaphies for inguinal hernias by a single surgeon during August 2012-July 2016 at Chia-Yi Christian Hospital were enrolled in this retrospective study. Demographic, perioperative and follow-up data were obtained for analysis and review.

RESULTS

Of the 305 patients, 261 patients had unilateral TEP herniorrhaphy and 44 patients had bilateral TEP herniorrhaphy. The mean operation time for the unilateral TEP herniorrhaphy group was 59.8 min, and for the bilateral TEP herniorrhaphy group it was 85.2 min (p < 0.001). Seven of 261 (2.7%) patients had metachronous contralateral hernia after unilateral TEP herniorrhaphy. There were no statistically significant differences in any of the outcome variables when comparing the sequential and simultaneous primary bilateral TEP herniorrhaphies.

CONCLUSIONS

Without routine contralateral exploration, the incidence of metachronous contralateral hernia was 2.7% (7/261) in unilateral hernia patients. This is acceptable as metachronous hernia also occurred in 3.2% of patients with negative contralateral exploration according to our literature review. Sequential and simultaneous bilateral primary TEP herniorrhaphy outcomes were similar. We conclude that no exploration for the other groin is a justified decision for unilateral inguinal hernia patients.

Cartilage MRI T2∗ relaxation time and perfusion changes of the knee in a 5/6 nephrectomy rat model of chronic kidney disease

OBJECTIVE

Chronic kidney disease (CKD) is characterized by metabolic disturbances in calcium and phosphorus homeostasis as kidney function declines. Alterations in blood perfusion in bone resulting from arteriosclerosis of bone vessels may relate to the progression of CKD. Herein, change in dynamic contrast enhanced (DCE) MRI parameters (A: amplitude, k_el: elimination constant, and k_ep: permeability rate constant) and MRI T2^∗ relaxation time of the knee cartilage were measured in a rodent nephrectomy model in order to (1) examine the relationship of peripheral blood perfusion to CKD and (2) demonstrate the feasibility of using DCE-MRI parameters and MRI T2^∗ as imaging biomarkers to monitor disease progression.

DESIGN

Two groups of male Sprague-Dawley rats received either (1) no intervention or (2) 5/6 nephrectomy.

RESULTS

We found that the CKD group (compared with the control group) had lower A and k_el values and similar k_ep value in the lateral and medial articular cartilages beginning at 12 weeks (P < 0.05); statistically significantly higher T2^∗ values in the lateral and medial articular cartilages beginning at 18 weeks (P < 0.05); statistically significantly decreased inner luminal diameter of the popliteal artery, and altered structure of the lateral and medial articular cartilages (P < 0.05).

CONCLUSION

Perfusion deficiency and CKD may be related. DCE parameters and MRI T2^∗ could serve as imaging biomarkers of cartilage degeneration in CKD progression.

Abnormal perfusion in patellofemoral subchondral bone marrow in the rat anterior cruciate ligament transection model of post-traumatic osteoarthritis: a dynamic contrast-enhanced magnetic resonance imaging study

OBJECTIVE

Although anterior cruciate ligament (ACL) injury is a well-recognized risk factor for developing knee post-traumatic osteoarthritis (PTOA), the process in the patellofemoral (PF) joint after ACL injury is still under-researched. Our aim was to investigate the perfusion changes in PF subchondral bone marrow in the rat ACL transection (ACLX) model of PTOA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

DESIGN

Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group): a normal control group and groups receiving ACLX and sham-surgery, respectively, in the right knee. Perfusion parameters in the patellar and femoral subchondral bone marrows of all rats were measured on DCE-MRI at 0, 4, 8, and 16 weeks after respective treatment. After the last MRI at week 16, the rats were sacrificed and their right knees were harvested for histologic examination. In addition, to observe the long-term histologic change in PF joints, 9 additional rats (n = 3 in each group) were included and sacrificed at week 32 for histologic examination.

RESULTS

In the ACLX group vs the sham and control groups, the perfusion parameters were significantly changed in both patellar and femoral subchondral bone marrows at week 16. Histologic examination revealed cartilage defects in ACLX rats at 32 weeks after surgery.

CONCLUSIONS

These data point to a possible functional relationship between subchondral bone marrow perfusion abnormalities and cartilage breakdown in PTOA. Moreover, the perfusion parameters derived from DCE-MRI can potentially serve as biomarkers of early OA.

Targeting post-translational modifications of histones for cancer therapy

Post-translational modifications (PTMs) on histones including acetylation, methylation, phosphorylation, citrullination, ubiquitination, ADP ribosylation, and sumoylation, play important roles in different biological events including chromatin dynamics, DNA replication, and transcriptional regulation. Aberrant histones PTMs leads to abnormal gene expression and uncontrolled cell proliferation, followed by development of cancers. Therefore, targeting the enzymes required for specific histone PTMs holds a lot of potential for cancer treatment. In this review article, we retrospect the latest studies in the regulations of acetylation, methylation, and phosphorylation of histones. We also summarize inhibitors/drugs that target these modifications for cancer treatment.

Saturated fatty acid induces cancer stem cell-like properties in human hepatoma cells

Hepatic steatosis has been reported to be a risk factor for the development of liver cancer. The underlying mechanism for carcinogenesis remains to be elucidated. It has been postulated that cancer stem cells (CSCs) within tumor tissues are a subset of cells with stem cell properties of self-renewal and undifferentiation. The purpose of this study was to investigate the effects of a saturated fatty acid, palmitate (PA), on CSC-like properties of human hepatoma HepG2 cells. We investigated the effects of PA on HepG2 cells and primary rat hepatocytes (PRH) by exposing them to PA to induce lipid accumulation. Significant fat accumulation was observed by Oil Red O staining in cells exposed to PA, and it was accompanied by significant increase in NFκB (p65) nuclear translocation in HepG2 cells. Notably, PA significantly enhanced the sphere forming ability of HepG2 cells, but not PRH. Furthermore, PA significantly increased stemness gene expressions of Sox2 and Oct4, and sonic hedgehog (Shh) production. Notably, NFκB inhibitors, N-Acetyl-L-cysteine and pyrollidine dithiocarbamate, and a NOX inhibitor, diphenyleneiodonium, significantly attenuated PA-induced sphere forming ability of HepG2 cells. Our results suggest that lipid accumulation may not only induce pro-inflammatory responses in hepatocytes but may also activate CSC-like properties of hepatoma cells through NFκB activation.

Genetic polymorphisms and tissue expression of interleukin-22 associated with risk and therapeutic response of gastric mucosa-associated lymphoid tissue lymphoma

Chronic Helicobacter pylori-stimulated immune reactions determine the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. We aimed to explore the genetic predisposition to this lymphoma and its clinical implication. A total of 68 patients and 140 unrelated controls were genotyped for 84 single-nucleotide polymorphisms in genes encoding cytokines, chemokines and related receptors that play important roles in T cell-mediated gastrointestinal immunity. Five genotypes in IL-22, namely CC at rs1179246, CC at rs2227485, AA at rs4913428, AA at rs1026788 and TT at rs7314777, were associated with disease susceptibility. The former four genotypes resided in the same linkage disequilibrium block (r(2)=0.99) that conferred an approximately threefold higher risk. In vitro experiments demonstrated that co-culturing peripheral mononuclear cells or CD4(+) T cells with H. pylori stimulated the secretion of interleukin-22 (IL-22), and that IL-22 induced the expression of antimicrobial proteins, RegIIIα and lipocalin-2, in gastric epithelial cells. Furthermore, patients with gastric tissue expressing IL-22 were more likely to respond to H. pylori eradication (14/22 vs 4/19, P<0.006). We conclude that susceptibility of gastric MALT lymphoma is influenced by genetic polymorphisms in IL-22, the product of which is involved in mucosal immunity against H. pylori and associated with tumor response to H. pylori eradication.

Therapeutic ROS targeting of GADD45γ in the induction of G2/M arrest in primary human colorectal cancer cell lines by cucurbitacin E

Cucurbitacin E (CuE) or α-elaterin is a natural compound previously shown to be an antifeedant as well as a potent chemopreventive agent against several types of cancer. The present study investigated the anticancer effects of CuE on colorectal cancer (CRC) using primary cell lines isolated from five CRC patients in Taiwan, Specifically, we explored the anti-proliferation and cell cycle G2/M arrest induced by CuE in CRC cells. MPM-2 flow cytometry tests show that CuE-treated cells accumulated in metaphase (CuE 2.5-7.5 μM). Results further indicate that CuE produced G2/M arrest as well as the downregulation of CDC2 and cyclin B1 expression and dissociation. Both effects increased proportionally with the dose of CuE; however, the inhibition of proliferation, arrest of mitosis, production of reactive oxygen species (ROS), and loss of mitochondrial membrane potential (ΔΨm) were found to be dependent on the quantity of CuE used to treat the cancer cells. In addition, cell cycle arrest in treated cells coincided with the activation of the gene GADD45(α, β, γ). Incubation with CuE resulted in the binding of GADD45γ to CDC2, which suggests that the delay in CuE-induced mitosis is regulated by the overexpression of GADD45γ. Our findings suggest that, in addition to the known effects on cancer prevention, CuE may have antitumor activities in established CRC.

Slug is temporally regulated by cyclin E in cell cycle and controls genome stability

The transcriptional repressor Slug is best known to control epithelial-mesenchymal transition (EMT) and promote cancer invasion/metastasis. In this study, we demonstrate that Slug is temporally regulated during cell cycle progression. At G1/S transition, cyclin E-cyclin-dependent kinase 2 mediates the phosphorylation of Slug at Ser-54 and Ser-104, resulting in its ubiquitylation and degradation. Non-phosphorylatable Slug is markedly stabilized at G1/S transition compared with wild-type Slug and greatly leads to downregulation of DNA synthesis and checkpoint-related proteins, including TOP1, DNA Ligase IV and Rad17, reduces cell proliferation, delays S-phase progression and contributes to genome instability. Our results indicate that Slug has multifaceted roles in cancer progression by controlling both EMT and genome stability.

Assessment of cam-type femoroacetabular impingement by ultrasonography: value of anterior femoral distance measurements

PURPOSE

To retrospectively determine the reproducibility and performance of a quantitative measurement for cam-type femoroacetabular impingement (FAI) designated as the anterior femoral distance (AFD) of the femoral head-neck junction identified at ultrasonography (US).

MATERIALS AND METHODS

72 patients with clinically suspected FAI were retrospectively evaluated, and US studies were performed during a 20-month period. Of these, we selected 53 patients who underwent subsequent magnetic resonance (MR) arthrography and had adequate recorded US images. All the longitudinal US images of the anterior and anterosuperior contours of the femoral head-neck junction were recorded by a radiologist. 33 of these US images were also recorded by a technician. An alpha angle of > 55° on MR arthrography was indicative of cam-type FAI. Two independent radiology residents blinded to the clinical data and MR arthrography measured the maximal femoral head-neck overgrowth defined as the AFD on US (AFD-US). Reproducibility was assessed using intra-class correlation coefficients (ICCs) and Bland-Altman plots, and diagnostic performance was assessed using receiver operating characteristic (ROC) analysis.

RESULTS

AFD-US showed high intra- and inter-rater agreement (ICC = 0.913 - 0.968) in all measurements and good reproducibility among different operators in the anterior contour measurements (ICC = 0.881) but not in the anterosuperior contour measurements (ICC = 0.196). An AFD-US cut-off value of 4.0 mm in the anterior contour yielded the greatest sensitivity (80.9 %) and specificity (87.5 %) for the diagnosis of cam-type FAI by ROC analysis.

CONCLUSION

AFD-US of the anterior contour of the femoral head-neck junction is helpful in diagnosing cam-type FAI.

Streptococcus agalactiae infective endocarditis with large vegetation in a patient with underlying protein S deficiency

We present a case of a patient with underlying protein S deficiency who suffered from infective endocarditis with a large anterior mitral leaflet (AML) mass of approximately 4.5 cm in length. Intraoperative transesophageal echocardiography (TEE) revealed the mass at the AML base and a rupture of the posterior mitral leaflet chordae tendinae. The vegetation's large size may have been caused by one or more of three factors: location, underlying disease, and the microorganism causing infection. Patients with protein S deficiency are prone to thromboembolic events during cardiac surgery. Infective endocarditis caused by Streptococcus agalactiae usually has a poor prognosis, and, thus, early surgery is recommended.

Hoffa fracture: should precautions be taken during fixation and rehabilitation?

A coronal fracture of a femoral condyle (Hoffa fracture) is an unusual injury and there are only a handful of reports discussing it. We report a case of a 52-year-old worker who fell from a height, suffering lower limb injuries, including a Hoffa fracture with comminution, and had problems with malunion during the postoperative period. Clinicians should be aware that rehabilitation programmes need to be tailored to the method of fixation used to manage this uncommon fracture pattern.

Catastrophic gastrointestinal manifestations of post-transplant lymphoproliferative disorder

Post-transplant lymphoproliferative disorder is a rare complication after bone marrow transplantation and frequently involves gastrointestinal tract, but the endoscopic characteristics and catastrophic clinical manifestations in adults have not been discussed in detail. We report a 35-year-old allogeneic bone marrow transplantation recipient who presented with recurrent gastrointestinal bleeding. Ulcerative nodular lesions were noted in stomach, duodenum and ileum on endoscopy but were not biopsied because of thrombocytopenia. Obstruction and perforation of small intestine occurred 5 months after bone marrow transplantation and was managed with surgery. Histopathology revealed the diagnosis of Epstein-Barr virus related post-transplant lymphoproliferative disorder. Rituximab was given after operation but repeated intestinal perforation supervened and resulted in mortality. The characteristic endoscopic and radiographic features are presented. Recognition of these characteristic endoscopic and radiographic findings with histological confirmation is crucial in making early diagnosis, and prompt treatment may prevent gastrointestinal complications and mortality.

Effects of passivation treatments on titanium alloy with nanometric scale roughness and induced changes in fibroblast initial adhesion evaluated by a cytodetacher

Passivation treatments of titanium alloy alter not only its nanosurface characteristics of oxides and ion release but also surface roughness (Ra), and wettability as well, where nanosurface characteristics of oxides include chemistries of oxides, amphoteric-OH groups adsorbed on oxides, and oxide thickness. Consequently, the passivation treatment affects the alloy's cyto-comparability. In this study, we polish specimens to achieve nanometric scale roughness. In addition, treatment effects are evaluated for surface topology, roughness, wettability, and responses of fibroblasts consisting of MTT assay, initial adhesion strength, and morphology. The initial adhesion strength is measured using a cyto-detacher that achieves nano-Newton resolution. Results reveal that (1) the treatment effects on the percentage of Ti--OH basic groups and wettability are nearly collinear; (2) the Ra of passivated Ti-6Al-4V ranges from 1.9 to 7.4 nm; (3) the initial adhesion strength of fibroblast ranges from 58 to 143 nN, and it is negatively correlated to the Ra; (4) the passivation results in distinguishable morphologies, which further substantiate the negative correlation between cell initial adhesion force and Ra; and (5) our results fall short of confirming previous reports that found positively charged functional groups promoting fibroblast attachment and spread. Potential causes of the inconsistency are addressed.

Comparison of epidermal growth factor receptor mutations between primary and corresponding metastatic tumors in tyrosine kinase inhibitor-naive non-small-cell lung cancer

BACKGROUND

Mutations of the epidermal growth factor receptor (EGFR) gene in non-small-cell lung cancer (NSCLC) patients predict the patients who will respond to EGFR tyrosine kinase inhibitor (TKI) treatment. A recent study has suggested that 33% of NSCLC showed primary tumor/metastasis discordance of EGFR expression by immunohistochemistry analysis. We intended to find out whether the EGFR mutations of primary lung cancers are concordant to that of corresponding metastatic tumors.

MATERIALS AND METHODS

We analyzed EGFR exons 18-21 from paired primary and metastatic tumors in 67 lung cancer patients who had not received TKI before tissues were sampled.

RESULTS

Using the direct sequencing method, 9 of 18 (50%) patients with EGFR mutation-positive primary lung tumors had lost the mutations in metastases. For 26 patients who were EGFR mutation positive in the metastatic tumors, 17 (65%) were negative in the primary tumors. We analyzed these paired tissues with discrepant EGFR mutations by the Scorpion Amplified Refractory Mutation System assay. Finally, the discordant rate reached 27% (18 of 67 cases).

CONCLUSION

EGFR mutations in primary lung tumors do not always reflect the same situation in metastases. Analysis of EGFR mutations in the primary lung tumor would be inadequate for planning the use of TKI for advanced NSCLC.

Frequent epidermal growth factor receptor gene mutations in malignant pleural effusion of lung adenocarcinoma

Malignant pleural effusions (MPEs) are often observed in lung cancer, especially adenocarcinoma. Epidermal growth factor receptor (EGFR) gene mutations are usually detected in lung adenocarcinoma. The purpose of the present study was to investigate the EGFR mutation rate in MPEs of lung adenocarcinoma. Between June 2005 and December 2006, 136 MPEs from lung adenocarcinoma were collected for EGFR mutation detection. In addition, between April 2001 and November 2004, 91 surgically resected specimens of lung adenocarcinoma from patients without MPEs were assessed for EGFR mutation. The EGFR mutation rate was significantly higher in the patients with MPEs than in the patients without (68.4% versus 50.5%). The EGFR mutation rate in patients with MPEs was not associated with sex, smoking history, age or cancer stage. By multivariate analysis, an age of <65 yrs, never smoking, Eastern Cooperative Oncology Group performance status 0-1, and EGFR mutation were significantly associated with a longer overall survival for lung adenocarcinoma patients with MPEs. The patients with malignant pleural effusions related to lung adenocarcinoma had a higher epidermal growth factor receptor gene mutation rate than the patients from whom surgically resected specimens were taken. Epidermal growth factor receptor tyrosine kinase inhibitors may be the treatment of choice for lung adenocarcinoma with malignant pleural effusions in east Asia.

Effects of nano-surface properties on initial osteoblast adhesion and Ca/P adsorption ability for titanium alloys

Titanium alloys (Ti6Al4V), while subjected to high temperature surface treatment, experience altered nano-surface characteristics. The effects of such surface treatments are examined, including the initial adhesion force experienced by osteoblasts, the Ca/P adsorption capability, and the nano-surface properties, including the amounts of amphoteric Ti-OH groups, surface topography, and surface roughness. The initial adhesion force is considered a quantitative indicator of cyto-compatibility in vitro. Previously, a cyto-detacher was applied in a pioneer attempt measuring the initial adhesion force of fibroblasts on a metal surface. Presently, the cyto-detacher is further applied to evaluate the initial adhesion force of osteoblasts. Results reveal that (1) titanium alloys subjected to heat treatment could promote the adsorption capability of Ca and P; (2) titanium alloys subjected to heat treatment could have higher initial osteoblast adhesion forces; (3) the adhesion strength of osteoblasts, ranging from 38.5 to 58.9 nN (nanonewtons), appears stronger for rougher surfaces. It is concluded that the heat treatment could have impacted the biocompatibility in terms of the initial osteoblast adhesion force and Ca/P adsorption capability.

Antibiotic-loaded cement articulating spacer for 2-stage reimplantation in infected total knee arthroplasty: a simple and economic method

We presented a simple and economic method of preparing articulating antibiotic-loaded cement spacers for treatment of infection after total knee arthroplasty. From 1996 to 2004, 28 infected total knee arthroplasties were treated with 2-stage reimplantation. Static spacers were used in 7 knees, and articulating spacers were used in 21 knees. A minimum of 2 years' follow-up after final treatment was evaluated. In the static group, 1 (14%) knee had recurrence of infection. In the articulating group, 2 (9%) knees had recurrence of infection with the original organism. Patients receiving articulating spacer had better range of motion, better knee score, and less bone loss than patients with static spacer.

Magnolol protects against cerebral ischaemic injury of rat heatstroke

1. Free radicals mediate cerebral ischaemic injury associated with heatstroke. Magnolol, an active component of Magnolia officinalis, is 1000-fold more potent than alpha-tocopherol in inhibiting lipid peroxidation in rat mitochondria. The aim of the present study was to ascertain whether magnolol attenuated cerebral ischaemic injury and free radical formation associated with heatstroke. 2. Urethane-anaesthetized rats were exposed to heat stress (ambient temperature 42 degrees C) to induce heatstroke. Controlled rats were exposed to 24 degrees C. Mean arterial pressure, cerebral perfusion pressure and cerebral blood flow after the onset of heatstroke were all significantly lower than in control rats. However, colonic temperature, intracranial pressure, heart rate, cerebral free radicals, lipid peroxidation and the neuronal damage score were greater after the onset of heatstroke. 3. Magnolol (20 or 40 mg/kg, i.v.) significantly attenuated the heatstroke-induced hyperthermia, arterial hypotension, intracranial hypertension, cerebral ischaemia and neuronal damage and increased free radical formation and lipid peroxidation in the brain. The extracellular concentrations of ischaemic (e.g. glutamate and lactate/pyruvate ratio) and damage (e.g. glycerol) markers in the corpus striatum were increased after the onset of heatstroke. Magnolol significantly attenuated the increase in striatal ischaemia and damage markers associated with heatstroke. 4. Thus, it appears that magnolol has impressive effects against heatstroke reactions.

Consumption of flea faeces and eggs by larvae of the cat flea, Ctenocephalides felis

The effects of the consumption of flea faeces and non-viable eggs on larval development in the cat flea Ctenocephalides felis (Bouché) (Siphonaptera: Pulicidae) were investigated. Only 13.3% of larvae developed into adults when fed a diet of male or female flea faeces alone; however, 90% of larvae developed into adults when fed on flea faeces supplemented with non-viable flea eggs. When fed with non-viable eggs alone, larvae did not develop into adults. Nevertheless, non-viable eggs may provide critical supplemental nutrients, lacking in flea faeces and required for larval development. None of the larvae fed on flea faeces or non-viable eggs alone formed a cocoon. A diet of flea faeces alone significantly extended the second as well as third larval stadia compared to larvae fed on diets containing non-viable eggs. It is suggested that the cannibalism of fertile eggs may limit population growth in the cat flea.

Fluoroalkylated polyethylene glycol as potential surfactant for perfluorocarbon emulsion

So far, perfluorocarbon (PFC) emulsions have been manufactured based mainly on two surfactants, Pluronic F-68 and egg yolk phospholipids (EYP) for clinical use. However, they have been documented to induce inflammatory or allergic responses when PFC emulsions were injected into human bloodstream. The cause of these side effects is associated with the phagocytosis of emulsified PFC microparticles by cells such as macrophages. In order to lessen the side effects, it is logic to develop surfactants, which are more phagocytosis-resistant and biocompatible. In this study, a perfluoroalkylated polyethylene glycol (R(F)-PEG) surfactant was synthesized by reacting perfluorooctanoyl chloride (C7F15COCl) with PEG of molecular weigh 8000. Both R(F)-PEG 8000 and EYP were used to make PFC emulsions separately by an ultrasonic homogenizer. Individual PFC emulsions were then incubated with mouse macrophage J774A.1 cells to examine the degree of phagocytosis. From microscopic observation of cell morphology, our results showed that the process of phagocytosis was retarded to a large extend using the R(F)-PEG surfactant. We also harnessed 19F-NMR to quantitatively detect the amount of PFC emulsions phagocytosed by J774A.1 cells. 19F-NMR result was consistent with the qualitative microscopic observation aforementioned.

The distinct roles that Gln-192 and Glu-217 of factor IX play in selectivity for macromolecular substrates and inhibitors

In this paper, we report functional characterization of positions 192 and 217 (chymotrypsinogen numbering system) in human factor IX and discuss the distinction and similarity of these two sites among the blood coagulation factors. Recombinant factor IXQ192E (residue glutamine at position 192 replaced by glutamic acid), IXQ192K, IXE217D, and IXE217R proteins exhibited 11%, 46%, 39%, and 2% of the wild-type factor IX's clotting activity, respectively. Binding of these variants to factor VIIIa (FVIIIa) was inefficient compared to that of wild-type factor IX, and the dissociation constants doubled for IXQ192E, 3-fold higher for IXQ192K and 4-fold higher for both IXE217D and IXE217R. In the presence of FVIIIa, all variant factor IX hydrolyzed factor X at the catalytic efficiencies correlating with respective clotting activities. However, FVIIIa greatly enhanced the catalytic efficiency of both IXE217 variants to a greater extent (approximately 7 x 10(4)-fold) as compared to its effect on the wild-type factor IXa and the other two IXQ192 variants [by a factor of (1-2) x 10(4)]. Moreover, while both IXQ192 variants demonstrated small substrate selectivity similar to that of wild-type factor IXa, the selectivity of both IXE217 variants was greatly altered. Mutations at position 192 disturbed the interaction of factor IXa with physiological inhibitors. Although all variants formed an SDS-stable complex with antithrombin III (ATIII) equally well in the presence of heparin and were readily inhibited by ATIII in the absence of heparin, activated IXQ192K exhibited a slower stable complex formation with ATIII without heparin. On the other hand, only IXQ192E showed decreased interaction with TFPI. Our results demonstrate that positions 192 and 217 play different roles unique to factor IX in specifying the interaction of factor IX with substrates and inhibitors.

Postoperative 6-month and 1-year evaluation of health-related quality of life in total hip replacement patients

BACKGROUND AND PURPOSE

During the last decade, health-related quality of life (HRQOL) has been recognized as a principal outcome measure for total hip replacement (THR). However, most THR outcome studies in Taiwan have limited their assessments to the areas of pain relief and physical function. This study examined the effects of THR on quality of life.

METHODS

A longitudinal prospective study design was adopted. A total of 76 THR patients were enrolled. Disease specific (Harris Hip Score) and generic measures (SF-36) were determined before and after surgery. Postoperative evaluations were completed at 6 months and 1 year. Patient characteristics and related medical information were derived from chart data.

RESULTS

Significant improvement was found in HRQOL. This improvement was maintained at both 6-month and 1-year follow-up. Specifically, the mean Harris Hip Score improved from 44.7 to 88.9 at the 6-month postoperative evaluation, and further improved to 91.3 at the 1-year evaluation. In the SF-36, each domain of health status showed a significant improvement at 6-month and 1-year evaluations (p < 0.05 or p < 0.01).

CONCLUSIONS

The results of the Harris Hip Score and the SF-36 showed that THR not only relieved physical pain but also enhanced all aspects of quality of life. In addition to pain relief and improved physical function, improvements in role limitations due to physical or emotional problems were also significant. These findings indicate that a general health survey should be combined with a disease-specific scoring system to assess THR outcome.

Phonological studies of the new gas-induced agitated reactor using computational fluid dynamics

An ozone-induced agitated reactor has been found to be very effective in degrading industrial wastewater. However, the cost of the ozone generation as well as its short residence time in reactors has restricted its application in a commercial scale. An innovated gas-induced draft tube installed inside a conventional agitated reactor was proved to effectively retain the ozone in a reactor. The setup was demonstrated to significantly promote the ozone utilization rate up to 96% from the conventional rate of 60% above the onset speed. This work investigates the mixing mechanism of an innovated gas-induced reactor for the future scale-up design by using the technique of computational fluid dynamics. A three-dimensional flow model was proposed to compute the liquid-gas free surface as well as the flow patterns inside the reactor. The turbulent effects generated by two 45 degrees pitch-blade turbines were considered and the two phases mixing phenomena were also manipulated by the Eulerian-Eulerian techniques. The consistency of the free surface profiles and the fluid flow patterns proved a good agreement between computational results and the experimental observation.

Therapeutic effect of sheng-ji-san on pressure ulcers

In the present study, the effectiveness of sheng-ji-san (SJS) in promoting the healing of pressure ulcers was evaluated. Thirty-two patients with pressure ulcers were divided into two groups. The treated group received routine medical care combined with SJS treatment and the control group received only routine medical care. After three weeks, the treated group showed a significant reduction in both surface area and depth grade, while the control group showed no significant change. The reduction ratio of the surface area of the ulcer and the effectiveness ratio for the treated group were significantly higher than for the control group. Multiple Linear Regression Analysis revealed that only the SJS treatment was significantly associated with the reduction of surface area and that the use of SJS could independently explain the observed high effectiveness ratio and a relatively high Odds Ratio of 9.539. These results indicate that SJS is effective in promoting the healing of pressure ulcers and should be considered as an adjuvant to routine therapy.

Diminution of Phagocytosed Perfluorocarbon Emulsions Using Perfluoroalkylated Polyethylene Glycol Surfactant

Perfluorocarbon emulsions have been considered as potential blood substitutes for years due to their high capacity of dissolving respiratory oxygen and carbon dioxide. However, they have been reported to associate with side effects (e.g., flu-like syndrome) after being injected into animal's bloodstream. The cause of these side effects is related to the phagocytosis of perfluorocarbon emulsions by cells (e.g., macrophages). Inspired by the approach of using polyethylene glycol (PEG) to camouflage liposomes, we synthesized a perfluoroalkylated PEG (R(F)-PEG) surfactant to provide steric hindrance for decreasing phagocytosis of perfluorocarbon emulsions. The R(F)-PEG surfactant along with Pluronic F-68 and egg yolk phospholipid mediated perfluorocarbon emulsions were incubated individually with J774A.1 macrophages to examine the degree of phagocytosis. 19F NMR studies were used to quantitatively determine the amount of perfluorocarbon emulsions phagocytosed by macrophages. Results showed that the degree of phagocytosis was diminished to a large extent for perfluorocarbon microparticles emulsified by the R(F)-PEG surfactant.

Folate depletion and elevated plasma homocysteine promote oxidative stress in rat livers

This study was designed to determine whether nutritional folate depletion exerts hepatic oxidative stress in relation to elevated plasma homocysteine. To mimic various extents of folate depletion status in vivo, male Wistar rats were fed an amino acid-defined diet containing either 8 (control), 2, 0.5, or 0 mg folic acid/kg diet. After a 4-wk feeding period, the plasma and hepatic folate concentrations of the rats decreased significantly with each decrement of dietary folate. Folate depletion did not significantly affect two major liver antioxidants: reduced glutathione and alpha-tocopherol. Conversely, folate depletion decreased Cu-Zn superoxide dismutase and glutathione peroxidase activities, but had no effect on catalase activity in liver homogenates. Lipid peroxidation products, as measured by thiobarbituric acid-reactive substances, were significantly higher in livers of folate-depleted rats than in those of the controls. This occurrence of hepatic oxidative stress in folate-depleted rats was confirmed by demonstrating an increased susceptibility of livers of folate-depleted rats to lipid peroxidation induced by additional H2O2 or Fe(2+) treatments compared with the controls. Decreasing dietary folate intake resulted in graded increases in plasma homocysteine concentrations of folate-depleted rats. Elevated plasma homocysteine and decreased plasma and hepatic folate concentrations in folate-depleted rats were all strongly and significantly correlated with increased liver lipid peroxidation (/r/ > or = 0.58, P < 0.0003). These data demonstrate that folate depletion and elevated plasma homocysteine promote oxidative stress in rat livers.

Duck hepatitis B virus expresses a regulatory HBx-like protein from a hidden open reading frame

Duck hepatitis B viruses (DHBV), unlike mammalian hepadnaviruses, are thought to lack X genes, which encode transcription-regulatory proteins believed to contribute to the development of hepatocellular carcinoma. A lack of association of chronic DHBV infection with hepatocellular carcinoma development supports this belief. Here, we demonstrate that DHBV genomes have a hidden open reading frame from which a transcription-regulatory protein, designated DHBx, is expressed both in vitro and in vivo. We show that DHBx enhances neither viral protein expression, intracellular DNA synthesis, nor virion production when assayed in the full-length genome context in LMH cells. However, similar to mammalian hepadnavirus X proteins, DHBx activates cellular and viral promoters via the Raf-mitogen-activated protein kinase signaling pathway and localizes primarily in the cytoplasm. The functional similarities as well as the weak sequence homologies of DHBx and the X proteins of mammalian hepadnaviruses strongly suggest a common ancestry of ortho- and avihepadnavirus X genes. In addition, our data disclose similar intracellular localization and transcription regulatory functions of the corresponding proteins, raise new questions as to their presumed role in hepatocarcinogenesis, and imply unique opportunities for deciphering of their still-enigmatic in vivo functions.

Extracellular polymers of ozonized waste activated sludge

Effect of ozonation on characteristics of waste activated sludge was investigated in the current study. Concentrations of cell-bound extracellular polymers (washed ECPs) did not change much upon ozonation, whereas the sum of cell-bound and soluble extracellular polymers (unwashed ECPs) increased with increasing ozone dose. Washed ECPs in original sludge as divided by molecular weight distribution was 39% < 1,000 Da (low MW), 30% from 1,000 to 10,000 Da (medium MW), and 31% > 10,000 Da (high MW). It was observed that the low-MW fraction decreased, and the high-MW fraction increased in ozonized sludge. The unwashed ECPs were characterized as 44% in low MW, 30% in medium MW, and 26% in high MW. Both low-MW and medium-MW fractions of unwashed ECPs decreased while high-MW fraction increased in ozonized sludge. The dewaterability of ozonized sludge, assessed by capillary suction time (CST) and specific resistance to filtration (SRF), deteriorated with ozone dose. The optimal dose of cationic polyelectrolyte increased with increasing ozone dose. The production rate and the accumulated amount of methane gas of ozonized sludge were also higher.

Tunnel study of on-road vehicle emissions and the photochemical potential in Taiwan

Motor vehicle emission factors of carbon monoxide (CO) and non-methane volatile organic compounds (NMVOCs) were calculated inside the Chung-Cheng Tunnel of Kaohsiung in Taiwan. The results were compared with those model predictions from the Mobile Taiwan 2.0 model. Individual concentrations of 21 species of NMVOCs were also determined. Photochemical potential of NMVOCs was evaluated by using the maximum incremental reactivity (MIR). Field data showed that the integrated emission factors of CO and NMVOCs for actual fleet were 6.3 and 1.5 g/veh km, respectively. The error range of these factors may be up to 45%. The predicted values by the Mobile Taiwan 2.0 model closely matched the observed data. Concentrations of isopentane, 2-methylpentane, toluene and m,p-xylene were the dominant species of NMVOCs. The ratio of maximum incremental reactivity to NMVOCs concentration was 3.9, similar to those of the studies in the US Fort McHenry and Tuscarora Tunnel.

Identification of a new CA dinucleotide repeat in the human factor VIII gene

We describe the identification of a new CA dinucleotide repeat marker for the diagnosis of haemophilia A carriers. The marker (CA-6) is present in intron 6 as a single copy 5 kb upstream of exon 7. Of 195 and 118 X chromosomes from normal individuals and haemophilia A patients, respectively, we observed three alleles of CA-6 with 12-14 repetitions [(CA)(12-14)]. The frequencies were 0.5% and 0% for (CA)(12), 99% and 95.8% for (CA)(13), and 0.5% and 4.2% for (CA)(14) in normals and patients respectively. We conclude that the low polymorphism of the CA-6 marker renders it less useful for the diagnosis of Chinese haemophilia A carriers.

Hierarchical order of critical residues on the immunity-determining region of the Im7 protein which confer specific immunity to its cognate colicin

The directed mutagenesis study of the Im7 protein of colicin E7 revealed that three residues, D31, D35, and E39, located in the loop 1 and helix 2 regions of the protein were critical for initiating the complex formation with its cognate colicin E7. Interestingly, the importance of these three critical residues in conferring specific immunity to its own colicin was exhibited in a hierarchical order, respectively. Moreover, we found that existence of the three critical residues was common among the DNase-type Im proteins. Most likely the three residues of the DNase-type immunity proteins are critical for initiating the unique protein-protein interactions with their cognate colicin. In addition, replacement of the helix 2 of Im7 by the corresponding region of Im8 produced a phenotype of the mutant protein very similar to that of Im8. This result suggests that the DNase-type Im proteins indeed share a "homologous-structural framework" and evolution of the Im proteins may be engendered by minor amino acid changes in this specific immunity-determining region without causing structural alteration of the proteins.

Molecular and electrophysiological characterizations of fGluR3 alpha, an ionotropic glutamate receptor subunit of a teleost fish

Here we report the cloning and functional analysis of a cDNA encoding a functional glutamate receptor subunit of Oreochromis sp., a freshwater teleost fish. The deduced amino acid sequence of this cDNA clone, fGluR3 alpha, displays the highest sequence identity to that of the mammalian GluR3 subunit. Results of quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis indicated that the expression level of fGluR3 alpha in the cerebellum was much less than that in the telencephalon and optical lobe. Similar to its mammalian counterpart, variants of fGluR3 alpha were created by alternative splicing and RNA editing at the R/G site. The channel properties of homomeric fGluR3 alpha expressed in Xenopus oocytes were similar to those of the mammalian alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-preferring receptors. The rank order of agonist potency of the expressed fGluR3 alpha is AMPA > or = glutamate > or = quisqualate > domoate > or = kainate. This is the first functional glutamate receptor of teleost fish being demonstrated to be sensitive to AMPA. Furthermore, this study suggested a strong functional conservation of AMPA-preferring receptors in vertebrates.

Distant metastasis of gastric cancer is associated with elevated expression of the antimetastatic nm23 gene

To understand the clinical significance of nm23 gene expression in gastric cancer patients, the Nm23-H1 protein level of fresh resected specimens from a total of 37 gastric cancer patients was measured by Western blot analysis. The elevated nm23 expression group (Nm23-H1 protein level in tumor tissue greater than the 75th percentile value of patients) was significantly associated with the histologically differentiated type (P = 0.036). This group had a higher incidence of distant (hematogeneous) metastasis (P = 0.0023) and a lower 2-year disease-free survival rate (P = 0.033) than the non-elevated group. The result was not consistent with the previous assumption that nm23 is an antimetastatic gene for gastric cancer.