FBXL8 inhibits post-myocardial infarction cardiac fibrosis by targeting Snail1 for ubiquitin-proteasome degradation

Abnormal cardiac fibrosis is the main pathological change of post-myocardial infarction (MI) heart failure. Although the E3 ubiquitin ligase FBXL8 is a key regulator in the cell cycle, cell proliferation, and inflammation, its role in post-MI ventricular fibrosis and heart failure remains unknown. FBXL8 was primarily expressed in cardiac fibroblasts (CFs) and remarkably decreased in CFs treated by TGFβ and heart subjected to MI. The echocardiography and histology data suggested that adeno-associated viruses (AAV9)-mediated FBXL8 overexpression had improved cardiac function and ameliorated post-MI cardiac fibrosis. In vitro, FBXL8 overexpression prevented TGFβ-induced proliferation, migration, contraction, and collagen secretion in CFs, while knockdown of FBXL8 demonstrated opposite effects. Mechanistically, FBXL8 interacted with Snail1 to promote Snail1 degradation through the ubiquitin-proteasome system and decreased the activation of RhoA. Moreover, the FBXL8ΔC3 binding domain was indispensable for Snail1 interaction and degradation. Ectopic Snail1 expression partly abolished the effects mediated by FBXL8 overexpression in CFs treated by TGFβ. These results characterized the role of FBXL8 in regulating the ubiquitin-mediated degradation of Snail1 and revealed the underlying molecular mechanism of how MI up-regulated the myofibroblasts differentiation-inducer Snail1 and suggested that FBXL8 may be a potential curative target for improving post-MI cardiac function.

Analysis of risk factors for complications following transurethral resection of the prostate

OBJECTIVE

This study investigates the risk factors for complications following transurethral resection of the prostate and provides a reference for reducing postoperative complications.

PATIENTS AND METHODS

A retrospective analysis was conducted on 322 patients with benign prostatic hyperplasia who underwent transurethral resection of the prostate from April 2015 to January 2022. Among them, 214 patients had complete clinical and follow-up data. Clinical and follow-up data were collected, and both univariate and multivariate logistic regression analyses were performed to identify factors influencing the occurrence of postoperation transurethral resection of the prostate complications.

RESULTS

The incidence of complications after transurethral resection of the prostate was 19.16% (41/214). Among them, the incidence of Grade I-II complications was 14.96% (32/214), and Grade III-IV complications were 4.2% (9/214). The preoperative Quality of Life score (p<0.001) was identified as an independent risk factor for the occurrence of Grade I-II complications after transurethral resection of the prostate. The International Prostate Symptom Score (p=0.006) was identified as an independent risk factor for the occurrence of Grade III-IV complications after transurethral resection of the prostate.

CONCLUSIONS

The preoperative Quality of Life score is an independent risk factor for the occurrence of Grade I-II complications after transurethral resection of the prostate. The International Prostate Symptom Score is an independent risk factor for the occurrence of Grade III-IV complications after transurethral resection of the prostate.

Analysis of risk factors for stone remnants and recurrence after lateral decubitus percutaneous nephrolithotomy

OBJECTIVE

This study aims to explore the risk factors for stone remnants and recurrence after lateral decubitus percutaneous nephrolithotomy (PCNL), providing insights to enhance the stone-free rate and reduce the stone recurrence rate.

PATIENTS AND METHODS

A retrospective analysis was conducted on 356 patients with renal or upper ureteral stones who underwent lateral decubitus PCNL from January 2015 to August 2022. Among them, 271 patients had complete clinical and follow-up data. General clinical information, perioperative data, and follow-up data were collected. Univariate and multivariate logistic regression analyses were performed to identify risk factors for stone remnants and recurrence after lateral decubitus PCNL.

RESULTS

The stone-free rate after lateral decubitus PCNL was 88.6% (195/271), and the stone recurrence rate within three years was 28.1% (76/271). Stone size (p<0.001) and stone co-infection (p=0.047) were identified as independent risk factors for stone remnants after lateral decubitus PCNL. Multiple stones (p=0.003) were an independent risk factor for stone recurrence after lateral decubitus PCNL.

CONCLUSIONS

Stone size and stone co-infection are independent risk factors for stone remnants after lateral decubitus PCNL. Multiple stones are an independent risk factor for stone recurrence after lateral decubitus PCNL.

["Double Grooves-Double Rings" technique of transurethral Thulium laser enucleation of the prostate: learning curve of single surgeon]

Objective: To evaluate the learning curve of the "Double Grooves-Double Rings" (DGDR) technique of transurethral Thulium laser enucleation of the prostate (ThuLEP) for benign prostatic hyperplasia (BPH) by a single surgeon. From June 2021 to July 2022, 84 patients mean age (69.0±8.0) years,preoperative prostate volume (90.9±40.3)ml with BPH underwent ThuLEP in the Department of Urology, Peking University First Hospital.Performed by a single surgeon who had no experience of transurethral resection of prostate (TURP) and any laser surgeries. The case scatter plots with the best fitting line were drawn to analyze the learning curve. According to the date of the surgeries, the patients were equally divided into three learning stages (28 patients for each group). The T-PSA,prostate volume,operative time,enucleation time, enucleation efficiency,catheter indwelling time, hemoglobin drop and perioperative complications (including re-TURP, blood transfusion, stress incontinence≥3 months and urethral stricture) were compared among the groups. The learning curve was divided into three stages, and the cutting point was shown on the 14^th case. Except the prostate volume [stage1 (75.7±30.7) ml, stage2 (93.40±39.6)ml, stage3 (103.5±46.2) ml, P<0.05], there was no significant difference of the baseline data between three groups (P>0.05). Compared with those of stage 1(100.6±24.7) min,(0.55±0.22) g/min, a statistically significant improvement was observed in both of the operative time and the enucleation efficiency among stage 2[(84.5±36.6) min, (0.87±0.33) g/min and stage 3 (71.2±26.3) min, (1.27±0.45) g/min, P<0.05]. The learning curve of the DGDR technique for ThuLEP can be divided into three stages. A ThuLEP beginner can preliminarily master this technique after completing 14 cases.

ASIC1a involves the acid-mediated activation of pancreatic stellate cells associated with autophagy induction

The acidic tumor microenvironment (TME) of pancreatic cancer affects the physiological function of pancreatic stellate cells (PSCs), which in turn promotes cancer progression. Acid-sensing ion channel 1a (ASIC1a) is responsible for acidosis-related physiopathological processes. In this study, we investigated the effect of acid exposure on the activation and autophagy of PSCs, and the role of ASIC1a in these events. The results showed that acidic medium upregulated the expression of ASIC1a, induced PSCs activation and autophagy, which can be suppressed by inhibiting ASIC1a using PcTx1 or ASIC1a knockdown, suggesting that ASIC1a involves these two processes. In addition, the acid-induced activation of PSCs was impaired after the application of autophagy inhibitor alone or in combination with ASIC1a siRNA, meaning a connection between autophagy and activation. Collectively, our study provides evidence for the involvement of ASIC1a in the acid-caused PSCs activation, which may be associated with autophagy induction.

Loss of DP1 Aggravates Vascular Remodeling in Pulmonary Arterial Hypertension via mTORC1 Signaling

Rationale: Vascular remodeling, including smooth muscle cell hypertrophy and proliferation, is the key pathological feature of pulmonary arterial hypertension (PAH). Prostaglandin I₂ analogs (beraprost, iloprost, and treprostinil) are effective in the treatment of PAH. Of note, the clinically favorable effects of treprostinil in severe PAH may be attributable to concomitant activation of DP1 (D prostanoid receptor subtype 1).Objectives: To study the role of DP1 in the progression of PAH and its underlying mechanism.Methods: DP1 levels were examined in pulmonary arteries of patients and animals with PAH. Multiple genetic and pharmacologic approaches were used to investigate DP1-mediated signaling in PAH.Measurements and Main Results: DP1 expression was downregulated in hypoxia-treated pulmonary artery smooth muscle cells and in pulmonary arteries from rodent PAH models and patients with idiopathic PAH. DP1 deletion exacerbated pulmonary artery remodeling in hypoxia-induced PAH, whereas pharmacological activation or forced expression of the DP1 receptor had the opposite effect in different rodent models. DP1 deficiency promoted pulmonary artery smooth muscle cell hypertrophy and proliferation in response to hypoxia via induction of mTORC1 (mammalian target of rapamycin complex 1) activity. Rapamycin, an inhibitor of mTORC1, alleviated the hypoxia-induced exacerbation of PAH in DP1-knockout mice. DP1 activation facilitated raptor dissociation from mTORC1 and suppressed mTORC1 activity through PKA (protein kinase A)-dependent phosphorylation of raptor at Ser791. Moreover, treprostinil treatment blocked the progression of hypoxia-induced PAH in mice in part by targeting the DP1 receptor.Conclusions: DP1 activation attenuates hypoxia-induced pulmonary artery remodeling and PAH through PKA-mediated dissociation of raptor from mTORC1. These results suggest that the DP1 receptor may serve as a therapeutic target for the management of PAH.

Pancreatic sarcomatoid carcinoma: CT, MRI, and 18F-FDG PET/CT features

AIM

To investigate computed tomography (CT), magnetic resonance imaging (MRI), and combined 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/CT features of pancreatic sarcomatoid carcinoma (PSC).

MATERIALS AND METHODS

The hospital database was searched retrospectively for the patients with PSC confirmed at histopathology after surgery. Ten patients who underwent unenhanced and enhanced CT (n=4), unenhanced and enhanced MRI (n=2), ¹⁸F-FDG PET/CT (n=2), and both enhanced CT and ¹⁸F-FDG PET/CT (n=2) were enrolled. Two patients underwent additional delayed PET/CT. The maximum standardised uptake value (SUVmax) was measured on PET/CT images.

RESULTS

Eleven lesions were detected in 10 patients. Solid and cystic components (n=6), intratumoural haemorrhage (n=1), nodular calcification (n=2), main pancreatic duct dilatation resulted from lesion obstruction (n=5) or compression (n=3), cholangiectasis (n=5), vascular and peripheral organ invasion (n=5 and 6, respectively), hepatic and lymphatic metastases (n=4 and 2, respectively) were detected. All five lesions in four patients who underwent PET/CT showed intense FDG uptake on PET/CT with SUVmax (16, range 10.9-21.1). Increase of FDG uptake (SUVmax = 18.9, 20.1, and 27.3, respectively) was revealed on the delayed scan of three lesions in two patients.

CONCLUSIONS

PSCs were more commonly ill-defined solid cystic masses, which caused pancreatic duct obstruction/compression without pancreatic parenchymal atrophy, and these masses on PET/CT showed high FDG uptake on both initial and delayed PET/CT.

Osteoglycin attenuates cardiac fibrosis by suppressing cardiac myofibroblast proliferation and migration through antagonizing lysophosphatidic acid 3/matrix metalloproteinase 2/epidermal growth factor receptor signalling

Aims

Cardiac myofibroblasts (CMFs) play a crucial role in the progression of pathological fibrotic cardiac remodelling. The expression of osteoglycin (OGN) is increased in diseased hearts; however, the role of OGN in pathological cardiac remodelling is not understood. Here, we sought to determine the effect of OGN on cardiac interstitial fibrosis and investigate the molecular mechanisms of OGN in CMF activation and matrix production.

Methods and results

We found that OGN expression was significantly upregulated in mouse hearts in response to chronic 14-day angiotensin II (Ang II) infusion. Mice lacking OGN (OGN-/-) exhibited enhanced cardiac interstitial fibrosis and significantly more severe cardiac dysfunction following Ang II infusion compared to wild-type mice. OGN deficiency did not alter blood pressure, nor had effect on transforming growth factor-beta signalling activation, but presented with increased proliferative activity in hearts. In vitro studies with isolated CMFs revealed that OGN deficiency significantly increased proliferation and migration and enhanced the transactivation of epidermal growth factor receptor (EGFR) signalling by Ang II. On the other hand, OGN overexpression in CMFs decreased their proliferation and migration via reducing EGFR activation. Overexpression of OGN also suppressed the shedding of membrane anchored EGFR ligand. Moreover, OGN was found to interact with a lysophosphatidic acid (LPA) receptor isoform 3 and thus to attenuate EGFR transactivation through blocking cell surface translocation of membrane type 1 matrix metalloproteinase (MT1-MMP) and subsequent pro-MMP-2 activation in a Ras homolog gene family, member A (RhoA)/Rho-associated, coiled-coil containing protein kinase (ROCK)-dependent manner.

Conclusion

These findings suggest that OGN negatively regulates cardiac fibrotic remodelling by attenuating CMF proliferation and migration through LPA3-mediated and Rho/ROCK-dependent inhibition of MT1-MMP translocation, MMP2 activation and EGFR transactivation.

Macrophage-Derived Legumain Promotes Pulmonary Hypertension by Activating the MMP (Matrix Metalloproteinase)-2/TGF (Transforming Growth Factor)-β1 Signaling

Objective—

Macrophages participate in the pathogenesis of pulmonary arterial hypertension (PAH). Lgmn (Legumain), a newly discovered cysteine proteinase belonging to the C13 peptidase family, is primarily expressed in macrophages; however, its roles in PAH remain unknown.

Approach and Results—

Herein, Lgmn was upregulated in lung tissues of PAH mice subjected to hypoxia plus SU5416 and PAH rats challenged with monocrotaline. Global Lgmn ablation and macrophage-specific ablation alleviated PAH compared with wild-type mice, evident from a reduction in right ventricular systolic pressure, the ratio of the right ventricular wall to the left ventricular wall plus the septum, the pulmonary vascular media thickness, and pulmonary vascular muscularization. Increased expression of ECM (extracellular matrix) proteins was correlated with MMP (matrix metalloproteinase)-2 activation and TGF (transforming growth factor)-β1 signaling in the PAs. Although Lgmn did not affect inflammatory cell infiltration and PA smooth muscle cell proliferation, it drove increased the synthesis of ECM proteins via MMP-2 activation. MMP-2 hydrolyzed the TGF-β1 precursor to the active form. An Lgmn-specific inhibitor markedly ameliorated PAH. Clinically, serum Lgmn levels were closely associated with the severity of idiopathic PAH.

Conclusions—

Our results indicate that Lgmn inhibition could be an effective strategy for preventing or delaying PAH.

Inhibition of CRTH2-mediated Th2 activation attenuates pulmonary hypertension in mice

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by progressive pulmonary artery (PA) remodeling. T helper 2 cell (Th2) immune response is involved in PA remodeling during PAH progression. Here, we found that CRTH2 (chemoattractant receptor homologous molecule expressed on Th2 cell) expression was up-regulated in circulating CD3⁺CD4⁺ T cells in patients with idiopathic PAH and in rodent PAH models. CRTH2 disruption dramatically ameliorated PA remodeling and pulmonary hypertension in different PAH mouse models. CRTH2 deficiency suppressed Th2 activation, including IL-4 and IL-13 secretion. Both CRTH2^+/+ bone marrow reconstitution and CRTH2^+/+ CD4⁺ T cell adoptive transfer deteriorated hypoxia + ovalbumin-induced PAH in CRTH2^-/- mice, which was reversed by dual neutralization of IL-4 and IL-13. CRTH2 inhibition alleviated established PAH in mice by repressing Th2 activity. In culture, CRTH2 activation in Th2 cells promoted pulmonary arterial smooth muscle cell proliferation through activation of STAT6. These results demonstrate the critical role of CRTH2-mediated Th2 response in PAH pathogenesis and highlight the CRTH2 receptor as a potential therapeutic target for PAH.

Chronic sun exposure is associated with distinct histone acetylation changes in human skin

BACKGROUND

Photoageing is attributed to continuous sunlight or artificial ultraviolet exposure and manifests as clinical and histological changes in skin. Epigenetic changes have been found to be involved in the pathogenesis of photoageing. However, the underlying mechanisms are unclear.

OBJECTIVES

To analyse histone modification patterns in sun-exposed and nonexposed skin, and to identify the abnormally histone-modified genes related to photoageing.

METHODS

Skin biopsies were collected from both the outer forearm (sun-exposed area) and the buttock (sun-protected area) in 20 healthy middle-aged female volunteers. Global histone H3/H4 acetylation and H3K4/H3K9 methylation statuses were assessed by enzyme-linked immunosorbent assay. Expression levels of histone acetyltransferases and histone deacetylases were measured by reverse-transcriptase quantitative polymerase chain reaction (qPCR) and Western blot. Chromatin immunoprecipitation combined with DNA microarray (ChIP-chip) assay with anti-acetyl-histone H3 antibody in a sun-exposed pool (combining six sun-exposed skin samples) and a nonexposed pool (combining six nonexposed skin samples) was conducted to explore the abnormally acetylated histone H3 genes related to photoageing; ChIP-qPCR was then used to verify the results of ChIP-chip.

RESULTS

We observed higher global histone H3 acetylation levels increased EP300 and decreased HDAC1 and SIRT1 expression in sun-exposed skin compared with matched nonexposed skin. Furthermore, the ChIP-chip assay showed that 227 genes displayed significant hyperacetylation of histone H3, and 81 genes displayed significant hypoacetylation of histone H3 between the two groups. Histone H3 acetylation levels on the promoters of PDCD5, ITIH5, MMP1 and AHR were positively correlated with the mRNA expression of the corresponding gene.

CONCLUSIONS

Chronic sun exposure-induced histone H3 hyperacetylation may play a critical role in the pathogenesis of skin photoageing.

RAGE-mediated extracellular matrix proteins accumulation exacerbates HySu-induced pulmonary hypertension

Aims

Extracellular matrix (ECM) proteins accumulation contributes to the progression of pulmonary arterial hypertension (PAH), a rare and fatal cardiovascular condition defined by high pulmonary arterial pressure, whether primary, idiopathic, or secondary to other causes. The receptor for advanced glycation end products (RAGE) is constitutively expressed in the lungs and plays an important role in ECM deposition. Nonetheless, the mechanisms by which RAGE mediates ECM deposition/formation in pulmonary arteries and its roles in PAH progression remain unclear.

Methods and results

Expression of RAGE and its activating ligands, S100/calgranulins and high mobility group box 1 (HMGB1), were increased in both human and mouse pulmonary arterial smooth muscle cells (PASMCs) under hypoxic conditions and were also strikingly upregulated in pulmonary arteries in hypoxia plus SU5416 (HySu)-induced PAH in mice. RAGE deletion alleviated pulmonary arterial pressure and restrained extracellular matrix accumulation in pulmonary arteries in HySu-induced PAH murine model. Moreover, blocking RAGE activity with a neutralizing antibody in human PASMCs, or RAGE deficiency in mouse PASMCs exposed to hypoxia, suppressed the expression of fibrotic proteins by reducing TGF-β1 expression. RAGE reconstitution in deficient mouse PASMCs restored hypoxia-stimulated TGF-β1 production via ERK1/2 and p38 MAPK pathway activation and subsequently increased ECM protein expression. Interestingly, HMGB1 acting on RAGE, not toll-like receptor 4 (TLR4), induced ECM deposition in PASMCs. Finally, in both idiopathic PAH patients and HySu-induced PAH mice, soluble RAGE (sRAGE) levels in serum were significantly elevated compared to those in controls.

Conclusions

Activation of RAGE facilitates the development of hypoxia-induced pulmonary hypertension by increase of ECM deposition in pulmonary arteries. Our results indicate that sRAGE may be a potential biomarker for PAH diagnosis and disease severity, and that RAGE may be a promising target for PAH treatment.

[Correlation analysis of serum secreted frizzled-related protein 5 levels with airway inflammation and insulin resistance in chronic obstructive pulmonary disease patients]

Objective: To investigate the relationship between serum secreted frizzled-related protein 5(sfrp5) levels, insulin resistance, and airway inflammation in patients with chronic obstructive pulmonary disease(COPD). Method: A total of 178 COPD patients visiting our respiratory outpatient clinic from February 2015 to January 2017 were enrolled, and 99 healthy control subjects from the same time period were selected. Serum sfrp5 levels were compared between the 2 groups. Serum sfrp5 and inflammatory cytokines in induced sputum were observed in the 4 subgroups: insulin resistant COPD group [homeostasis model assessment of insulin resistance (HOMA-IR)≥2.29], non-insulin resistant COPD group, non-COPD insulin resistant group, and healthy control group. Results: Serum sfrp5 levels were found to be significantly higher in the COPD group as compared to the healthy control group (t=-14.29, P<0.001). Serum sfrp5 levels in the insulin resistant COPD group [(8±3)ng/ml] were significantly lower than that of the non-insulin resistant COPD group [(10±5)ng/ml], non-COPD insulin resistant group [(13±3)ng/ml], and normal control group [(14±4)ng/ml, F=35.85, P<0.01]. The insulin resistant COPD group had higher levels of In(Homa-IR), as well as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in induced sputum as compared to the non-insulin resistant COPD group, non-COPD insulin resistant group, and healthy control group (F values were 64.968, 41.40, 64.15, respectively, P value <0.01 for all items). The non-insulin resistant COPD group had higher levels of In(HOMA-IR) as well as TNF-α and IL-6 in induced sputum as compared to the non-COPD insulin resistant group and healthy control group. FEV(1)/FVC and FEV(1)% predicted were significantly lower in the insulin resistant COPD group as compared to those of non-insulin resistant COPD group and non-COPD insulin resistant group, and healthy control group (F values were 2.481 and 8.37, respectively, P value<0.05 for all items). FEV(1)/FVC and FEV(1)% predicted were significantly lower in the non-insulin resistant COPD group as compared to those of the healthy control group and non-COPD insulin-resistant group. Serum sfrp5 levels were positively correlated to FEV(1)/FVC and FEV(1) predicted (r values were 0.466 and 0.412, respectively; P values were <0.001 and 0.007, respectively) and inversely correlated to In(HOMA-IR) and TNF-α and IL-6 in induced sputum (r values were -0.304, -0.459, -0.517, respectively; P values were <0.001, 0.002, <0.001, respectively). BMI, ln(HOMA-IR), and IL-6 in induced sputum were independent related factors (r(2) values were 0.286, 0.176, 14.69, respectively; P values were <0.01 for all items) Conclusion: Sfrp5 may be concurrently associated with COPD and insulin resistance; insulin resistance may be associated with airway inflammation and airflow limitation. Sfrp5 may be involved in the development of COPD and may be the key link by which insulin resistance exerts its effects on airway inflammation.

Osteoprotegerin Disruption Attenuates HySu-Induced Pulmonary Hypertension Through Integrin αvβ3/FAK/AKT Pathway Suppression

BACKGROUND

Pulmonary arterial remodeling characterized by increased vascular smooth muscle proliferation is commonly seen in life-threatening disease, pulmonary arterial hypertension (PAH). Clinical studies have suggested a correlation between osteoprotegerin serum levels and PAH severity. Here, we aimed to invhestigate vascular osteoprotegerin expression and its effects on pulmonary arterial smooth muscle cell proliferation in vitro and in vivo, as well as examine the signal transduction pathways mediating its activity.

METHODS AND RESULTS

Serum osteoprotegerin levels were significantly elevated in patients with PAH and correlated with disease severity as determined by the World Health Organization (WHO) functional classifications and 6-minute walking distance tests. Similarly, increased osteoprotegerin expression was observed in the pulmonary arteries of hypoxia plus SU5416- and monocrotaline-induced PAH animal models. Moreover, osteoprotegerin disruption attenuated hypoxia plus SU5416-induced PAH progression by reducing pulmonary vascular remodeling, whereas lentiviral osteoprotegerin reconstitution exacerbated PAH by increasing pulmonary arterial smooth muscle cell proliferation. Furthermore, pathway analysis revealed that osteoprotegerin induced pulmonary arterial smooth muscle cell proliferation by interacting with integrin α_vβ₃ to elicit downstream focal adhesion kinase and AKT pathway activation.

CONCLUSIONS

Osteoprotegerin facilitates PAH pathogenesis by regulating pulmonary arterial smooth muscle cell proliferation, suggesting that it may be a potential biomarker and therapeutic target in this disease.

Serum levels of tumor necrosis factor-related apoptosis-inducing ligand correlate with the severity of pulmonary hypertension

Pulmonary hypertension (PH) is a rapidly progressive disease that eventually leads to right heart failure and death. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptors (TRAIL-Rs) play an important role in the survival, migration, and proliferation of vascular smooth muscle cells. However, the association between serum TRAIL levels and PH is unknown. In this study, we assayed the serum soluble TRAIL (sTRAIL) levels in 78 patients with PH and 80 controls. The sTRAIL concentrations were elevated in the PH patients compared with the controls (138.76 ± 6.60 pg/mL vs. 80.14 ± 3.38 pg/mL, p < 0.0001). The presence of sTRAIL levels of >103 pg/mL could discriminate PH patients from healthy individuals, with a sensitivity of 75.6% and specificity of 81.2%. Moreover, elevated sTRAIL concentrations were associated with eventual pathological complications; this is consistent with the finding that sTRAIL levels decreased in patients who responded to treatment. In a hypoxia-induced PH mouse model, sTRAIL levels were significantly higher compared with those in normoxia mice, and clearly decreased when the mice were treated with treprostinil. The sTRAIL levels were positively correlated with right ventricular systolic pressure and the index of right ventricular hypertrophy. In conclusion, serum sTRAIL could be a biomarker for diagnosis and effective therapy for PH patients.

EP3 receptor deficiency attenuates pulmonary hypertension through suppression of Rho/TGF-β1 signaling

Pulmonary arterial hypertension (PAH) is commonly associated with chronic hypoxemia in disorders such as chronic obstructive pulmonary disease (COPD). Prostacyclin analogs are widely used in the management of PAH patients; however, clinical efficacy and long-term tolerability of some prostacyclin analogs may be compromised by concomitant activation of the E-prostanoid 3 (EP3) receptor. Here, we found that EP3 expression is upregulated in pulmonary arterial smooth muscle cells (PASMCs) and human distal pulmonary arteries (PAs) in response to hypoxia. Either pharmacological inhibition of EP3 or Ep3 deletion attenuated both hypoxia and monocrotaline-induced pulmonary hypertension and restrained extracellular matrix accumulation in PAs in rodent models. In a murine PAH model, Ep3 deletion in SMCs, but not endothelial cells, retarded PA medial thickness. Knockdown of EP3α and EP3β, but not EP3γ, isoforms diminished hypoxia-induced TGF-β1 activation. Expression of either EP3α or EP3β in EP3-deficient PASMCs restored TGF-β1 activation in response to hypoxia. EP3α/β activation in PASMCs increased RhoA-dependent membrane type 1 extracellular matrix metalloproteinase (MMP) translocation to the cell surface, subsequently activating pro-MMP-2 and promoting TGF-β1 signaling. Activation or disruption of EP3 did not influence PASMC proliferation. Together, our results indicate that EP3 activation facilitates hypoxia-induced vascular remodeling and pulmonary hypertension in mice and suggest EP3 inhibition as a potential therapeutic strategy for pulmonary hypertension.

Myeloid-derived suppressor cell function is diminished in aspirin-triggered allergic airway hyperresponsiveness in mice

BACKGROUND

Myeloid-derived suppressor cells (MDSCs) have recently been implicated in the pathogenesis of asthma, but their regulation in patients with aspirin-intolerant asthma (AIA) remains unclear.

OBJECTIVE

We sought to characterize MDSC accumulation and pathogenic functions in allergic airway inflammation mediated by COX-1 deficiency or aspirin treatment in mice.

METHODS

Allergic airway inflammation was induced in mice by means of ovalbumin challenge. The distribution and function of MDSCs in mice were analyzed by using flow cytometry and pharmacologic/gene manipulation approaches.

RESULTS

CD11b(+)Gr1(high)Ly6G(+)Ly6C(int) MDSCs (polymorphonuclear MDSCs [PMN-MDSCs]) recruited to the lungs are negatively correlated with airway inflammation in allergen-challenged mice. Aspirin-treated and COX-1 knockout (KO) mice showed significantly lower accumulation of PMN-MDSCs in the inflamed lung and immune organs accompanied by increased TH2 airway responses. The TH2-suppressive function of PMN-MDSCs was notably impaired by COX-1 deletion or inhibition, predominantly through downregulation of arginase-1. COX-1-derived prostaglandin E2 promoted PMN-MDSC generation in bone marrow through E prostanoid 2 and 4 receptors (EP2 and EP4), whereas the impaired arginase-1 expression in PMN-MDSCs in COX-1 KO mice was mediated by dysregulation of the prostaglandin E2/EP4/cyclic AMP/protein kinase A pathway. EP4 agonist administration alleviated allergy-induced airway hyperresponsiveness in COX-1 KO mice. Moreover, the immunosuppressive function of PMN-MDSCs from patients with AIA was dramatically decreased compared with that from patients with aspirin-tolerant asthma.

CONCLUSION

The immunosuppressive activity of PMN-MDSCs was diminished in both allergen-challenged COX-1 KO mice and patients with AIA, probably through an EP4-mediated signaling pathway, indicating that activation of PMN-MDSCs might be a promising therapeutic strategy for asthma, particularly AIA.

Vitamin D inhibits COX-2 expression and inflammatory response by targeting thioesterase superfamily member 4

Inadequate vitamin D status has been linked to increased risk of type 2 diabetes and cardiovascular disease. Inducible cyclooxygenase (COX) isoform COX-2 has been involved in the pathogenesis of such chronic inflammatory diseases. We found that the active form of vitamin D, 1,25(OH)2D produces dose-dependent inhibition of COX-2 expression in murine macrophages under both basal and LPS-stimulated conditions and suppresses proinflammatory mediators induced by LPS. Administration of 1,25(OH)2D significantly alleviated local inflammation in a carrageenan-induced paw edema mouse model. Strikingly, the phosphorylation of both Akt and its downstream target IκBα in macrophages were markedly suppressed by 1,25(OH)2D in the presence and absence of LPS stimulation through up-regulation of THEM4 (thioesterase superfamily member 4), an Akt modulator protein. Knockdown of both vitamin D receptor and THEM4 attenuated the inhibitory effect of 1,25(OH)2D on COX-2 expression in macrophages. A functional vitamin D-responsive element in the THEM4 promoter was identified by chromatin immunoprecipitation and luciferase reporter assay. Our results indicate that vitamin D restrains macrophage-mediated inflammatory processes by suppressing the Akt/NF-κB/COX-2 pathway, suggesting that vitamin D supplementation might be utilized for adjunctive therapy for inflammatory disease.

Electrolytic partitioning of uranium and plutonium based on a new type of electrolytic mixer-settler

The design of a new type of electroreduction mixer-settler for the partitioning of uranium and plutonium during the Purex process, which is featured with E-shaped cathodes and U-shaped anodes in settling chamber, is described and the operational results achieved using this equipment are presented. The results show that this new type of mixer-settler has excellent separation performances. The flow rate of organic feed solution is 3 mL/min and the flow ratio of feed solution (1BF) to aqueous back extraction stream (1BX) and to organic wash stream (1BS) is 4/1/1. For an organic feed of 84 g/L uranium and 1.40 ⁓ 2.64 g/L plutonium, both the separation factor of plutonium from uranium and that of uranium from plutonium are apparently higher than 104

Osteoblastogenesis regulation signals in bone remodeling

Bone remodeling is essential for adult bone homeostasis. The failure of this process often leads to the development of osteoporosis, a present major global health concern. The most important factor that affects normal bone remodeling is the tightly controlled and orchestrated regulation of osteoblasts and osteoclasts. The present review summarized the recent discoveries related to osteoblast regulation from several signals, including transforming growth factor-β, bone morphogenetic proteins, Wnt signal, Notch, Eph-Ephrin interaction, parathyroid hormone/parathyroid hormone-related peptide, and the leptin-serotonin-sympathetic nervous systemic pathway. The awareness of these mechanisms will facilitate further research that explores bone remodeling and osteoporosis. Future investigations on the endogenous regulation of osteoblastogenesis will increase the current knowledge required for the development of potential drug targets in the treatment of osteoporosis.

FDG-PET study of the bilateral subthalamic nucleus stimulation effects on the regional cerebral metabolism in advanced Parkinson disease

The aim of the study was to evaluate the changes in regional cerebral metabolic rate of glucose (rCMRGlu) induced by bilateral subthalamic nucleurs (STN) stimulation in advanced Parkinson's disease (PD). 18F-Fluorodeoxyglucose (FDG) PET data obtained before and one month after stimulation were analyzed with statistical parametric mapping (SPM). As a result of clinically effective bilateral STN stimulation, rCMRGlu increased in lateral globus pallidus (GP), upper brain stem, dorsolateral prefrontal cortex (DLPFC) and posterior parietal-occipital cortex, and decreased in the orbital frontal cortex and parahippocampus gyrus (p < 0.001). We conclude that the alleviation of clinical symptoms in advanced PD by bilateral STN stimulation may be the result of activation of both ascending and descending pathways from STN and of restoration of the impaired higher-order cortex functions.

High spatial resolution in vivo 2D (1)H magnetic resonance spectroscopic imaging of human muscles with a band-selective technique

This report demonstrates a 2D (1)H magnetic resonance spectroscopic imaging (MRSI) technique that can address some technical difficulties often encountered in MRS studies of human muscles. A preliminary application of this whole-slice technique in human skeletal muscles demonstrates clearly noticeable differences in (1)H metabolite spectra between different human muscles. This observation illustrates the importance of multi-voxel and high spatial resolution in a heterogeneous environment. This technique is robust, can be easily implemented on a commercial MR scanner, and should prove useful for investigators in both basic and clinical (1)H MRS studies.

Potential heating effect in the gravid uterus during MR HASTE imaging

Our purpose was to evaluate if temperature changes occur in maternal or fetal tissues during HASTE imaging.

METHODS

Pregnant pigs were scanned with the HASTE technique, and temperatures were measured with phase maps and temperature probes inserted into the amniotic fluid and fetal brain.

RESULTS

Fiberoptic probes showed that no heating occurred in fetal tissues or amniotic fluid during HASTE imaging.

CONCLUSION

Our current HASTE protocols do not deposit a significant amount of heat in the gravid uterus. J. Magn. Reson. Imaging 2001;13:856-861.

[The risk of sustained amenorrhea in patients with systemic lupus erythematosus receiving intermittent pulse cyclophosphamide therapy]

OBJECTIVE

To determine the risk of sustained amenorrhea in premenopausal women with systemic lupus erythematosus (SLE) receiving intermittent pulse cyclophosphamide (CTX) therapy.

METHODS

Prospectively comparing the amenorrhea rate of 51 cases receiving intermittent pulse cyclophosphamide therapy versus that of 22 cases receiving intermittent pulse methylprednisolone (MP) therapy.

RESULTS

The amenorrhea rate was higher in the CTX group (19.6%) than in the MP group (P = 0.025). In the CTX group, the amenorrhea rate of patients aged over 30 was higher than that of patients aged 30 or below 30 (P = 0.0018).

CONCLUSION

Pulse CTX therapy in fertile women with SLE is associated with increased rate of sustained amenorrhea, and the older the patient is, the higher risk for sustained amenorrhea the patient runs.

[Study on bolus cyclosphamide treatment for 64 cases of lupus nephritis]

OBJECTIVE

To report on the dosing, efficacy and side-effects of bolus cyclosphamide treatment for lupus nephritis (LN).

METHODS

64 consecutive cases of LN with 10 or more erythrocytes per high-power field, proteinuria (> 1 g of protein per day) and serum creatinine increased (> 133 mumol/L) were treated by bolus therapy with cyclophosphamide (CTX) given monthly for 6 months and then quarterly for 18 months.

RESULTS

49 patients had renal remission (defined as < 10 erythrocytes per high-power field, absence of cellular casts, excretion of < 1 g of protein per day and normal serum creatinine). The mean of doses was 1.1 g for each time (0.6-1.6 g), the mean of times of bolus CTX needed was 3.6 (1-8 times). The adverse events were amenorrhea (in 41% female patients), herpes zoster (in 13% patients) and hemorrhagic cystitis (in 1 patient).

CONCLUSION

The results indicate that monthly bolus CTX therapy is effective and safe for patients with LN. Its adverse effect is relatively not a serious problem.

Water modeled signal removal and data quantification in localized MR spectroscopy using a time-scale postacquistion method

We have previously shown the continuous wavelet transform (CWT), a signal-processing tool, which is based upon an iterative algorithm using a lorentzian signal model, to be useful as a postacquisition water suppression technique. To further exploit this tool we show its usefulness in accurately quantifying the signal metabolites after water removal. However, due to the static field inhomogeneities, eddy currents, and "radiation damping," the water signal and the metabolites may no longer have a lorentzian lineshape. Therefore, another signal model must be used. As the CWT is a flexible method, we have developed a new algorithm using a gaussian model and found that it fits the signal components, especially the water resonance, better than the lorentzian model in most cases. A new framework, which uses the two models, is proposed. The framework iteratively extracts each resonance, starting by the water peak, from the raw signal and adjusts its envelope to both the lorentzian and the gaussian models. The model giving the best fit is selected. As a consequence, the small signals originating from metabolites when selecting, removing, and quantifying the dominant water resonance from the raw time domain signal are preserved and an accurate estimation of their concentrations is obtained. This is demonstrated by analyzing (1H) magnetic resonance spectroscopy unsuppressed water data collected from a phantom with known concentrations at two different field strengths and data collected from normal volunteers using two different localization methods.

[The correlation between anticardiolipin antibodies and disease activity in patients with systemic lupus erythematosus]

This study was conducted to determine the prevalence and clinical association of anticardiolipin antibodies (ACA) in serum of patients with systemic lupus erythematosus (SLE). ACA (IgG, IgA, IgM) was measured by enzyme-linked immunosorbent assay (ELISA) in the serum sample of 87 patients of SLE. The prevalence rates of ACAIgG, ACAIgA and ACAIgM were 62.1%, 52.9% and 35.6% respectively. The titers of ACAIgG and ACAIgM were positively correlated with the disease activity (r = 0.2763, P = 0.044; r = 0.3294, P = 0.018); ACAIgG, ACAIgA and ACAIgM were negatively correlated with complement C3 (r = -0.4737, P = 0.000; r = -0.2990, P = 0.017; r = -0.2758, P = 0.029); and ACAIgG was negatively correlated with complement C4 (r = -0.4079, P = 0.005). The titers of ACAIgA in patients with thrombosis was higher than that in patients without thrombosis. The patients with central nervous system involvement (CNS-SLE) had significantly higher ACAIgG and ACAIgM titers, compared with those without CNS-SLE. The results indicate there is a correlation between ACA titers and disease activity. In patients with thrombosis, the titer of ACAIgA is higher, and in patients with CNS-SLE, the titers of ACAIgG and ACAIgM are higher.

[Studies on chemical constituents of the roots of Gypsophila oldhamiana Miq]

OBJECTIVE

To separate compounds from the root of Gypsophila oldhamiana.

METHOD

Chemical and chromatographic methods were used to separate the compounds. IR, MS, NMR were used to determine the structures of compounds.

RESULT

Compound pentacosanoic acid, lacceroic acid, beta-sitosterol, alpha-spinasterol, daucosterol and sucrose were identified.

CONCLUSION

All the above compounds were obtained from this genus for the first time.

Trial of antiepilepsirine (AES) in children with epilepsy

Antieplepsirine (AES) is a new antiepileptic drug (AED) which was originally extracted from a Chinese folk remedy, and is now chemically characterized and synthesized. Its chemical structure is different from those of other available AEDs. Animal experiments involving AES demonstrated significant antiepileptic activity. Only a few clinical studies of AES with open trial have been resorted, none of which were on children. A 6.5 month, add-on, double-blind, placebo-controlled, randomized, cross-over study on AES (10 mg/kg per day) was conducted on epileptic children (aged 1-14 years) refractory to treatment with standard AEDs. The seizure frequency was recorded, and the blood levels of AES and other co-medicated AEDs (phenobarbital, phenytoin, carbamazepine and valproate) were determined. Although not planned, patients or parents were allowed to refuse to cross-over to the alternate therapy. The results were compared to the children who crossed-over as well as for the entire group during the first 3 months of randomized treatment. A total of 58 children entered, but only 34/58 children completed the cross-over study. The 24 children whose parents refused to let them be crossed-over continued the original study treatment (AES or placebo) for the entire 6 months. There was no statistically significant difference in seizure control when the entire group of 58 patients was compared to a parallel study group for the first 3 months of therapy (P = 0.178). There was a significant difference (P<0.01) in seizure control between AES and placebo treatment for the 34 patients who completed the entire cross-over study. No significant changes were seen in the blood level of other AEDs, and no serious acute side effects were observed. The results of the present study indicate the efficacy of AES for epileptic children with refractory seizures.

[Chemical constituents of Phyllanthus urinaria L. and its antiviral activity against hepatitis B virus]

Studies on the chemical constituents of Phyllanthus urinaria and its antiviral activity against hepatitis B virus were completed. Eleven compounds have been isolated. Two of them are new compounds methyl ester dehydrochebulic acid and methyl brevifolin carboxylate. Antiviral experiments on HBsAg in vitro and liver damage caused by CCl4 have shown that. Phyllanthus urinaria possesses antiviral activities against HBV.

Characterization of hydroxyapatite film with mixed interface by Ar+ ion beam enhanced deposition

Ar+ ion beam enhanced deposition (IBED) was used to produce a hydroxyapatite (HA) film on polished titanium substrates. In this study, the HA ceramic target was sputtered by an argon-ion beam with an energy of 1.5 KeV, and the sputtered film was intermittently bombarded by energetic argon-ions at 60 KeV. An effective Ca-Ti mixed layer produced by the energetic argon-ion bombardment was confirmed by using Auger electron spectroscopy. The characteristics of the deposited films were evaluated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. XRD analysis revealed that the as-deposited film was amorphous, and a hydroxyapatite-type structure was obtained from the post-heat treatment of the deposited films. SEM observations showed that no distinct difference in surface morphology was found between the as-deposited and heat-treated samples for Ar+ IBED films, suggesting a strongly bonded HA film on the titanium substrate. In comparison with the HA target, some chemistry alterations were brought about in the deposited films, such as the incorporation of CO3, the loss of the OH groups and some distortion of the phosphate lattice.

In vivo bone marrow lipid characterization with line scan Carr-Purcell-Meiboom-Gill proton spectroscopic imaging

Line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging sequences have been used to extract lipid chemical composition indices in healthy adult bone marrow in the knee at 1.5 T. Since several spectroscopic echo readouts follow each excitation, the information acquired reflects a balance between spectral T2 decay processes and spectral resolution. To examine this balance in detail, data sets with two different echo spacings and spectral resolutions have been acquired to compare the information available from each in studies of bone marrow. Oils for which high field (7 T) proton spectra were recorded were used to evaluate the accuracy of lipid chemical composition indices extracted from the line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging methods at 1.5 T. The extension of the method to fast spectroscopic imaging of bone marrow with multiple echoes is demonstrated.

Cytochrome P-450scc-mediated oxidation of (20S)-22-thiacholesterol: characterization of mechanism-based inhibition

(20S)-22-thiacholesterol (1) is found to be a potent competitive inhibitor of pregnenolone biosynthesis from cholesterol by purified reconstituted bovine adrenal cytochrome P-450scc. The apparent dissociation constant Kd, determined from difference spectra, is 0.6 microM, close to the value from kinetic studies for the apparent inhibition constant, Ki, of 0.8 microM. Studies of the time course of pregnenolone production indicate that under turnover conditions the competitive inhibitor (1) is converted to a tighter binding inhibitor, shown to be (20S,22R)-22-thiacholesterol S-oxide (4), with high diastereoselectivity and in a time-dependent manner. Both the diastereomeric sulfoxides, (20S,22S)-22-thiacholesterol S-oxide (3) and (20S,22R)-22-thiacholesterol S-oxide (4), exhibit properties consistent with their being competitive versus cholesterol, but the (22R)-sulfoxide (4) binds approximately 10 times more tightly than the (22S) diastereomer (3). The apparent Kd values of sulfoxides 4 and 3 are 0.1 and 1.14 microM, respectively. EPR and absorption spectroscopic studies of enzyme-inhibitor complexes suggest direct coordination of the oxygen atom of the (22R)-sulfoxide (4) with the catalytic heme center. This implies that the inhibitor operates by directly blocking further reaction at the active site heme group, with a substantial lifetime of the enzyme-inhibitor complex.

[Chemical components of the leaves of Pistacia Chinensis Bge]

Six compounds have been isolated from the leaves of Pistacia chinensis, a species of Anacardiaceae family. Their structures were identified on the basis of UV, IR, NMR, and MS as gallic acid, m-digallic acid, quercetin, 6-0-galloyl arbutin-quercitrin and quercetin-3-0(6''-galloyl)-beta-D-glucosides.

[Chemical constituents of the leaves of Crataegus pinnatifida Bge. var. major N. E. Br]

Compounds were isolated from the aqueous extract of the leaves of Crataegus pinnatifida var. major and seven of them were identified as 2-(4-hydroxybenzyl)malic acid, quercetin, hyperin, vitexin, rhamnosylvitexin, diethylamine hydrochloride and sorbitol respectively by UV, IR, NMR, MS, some chemical techniques by comparison with the standard spectra of known compounds.

Structural characterization of the isoenzymatic forms of human myeloperoxidase: evaluation of the iron-containing prosthetic group

Myeloperoxidase (MPO) from human neutrophils has been purified and found to exist in three isoenzymatic forms, resolved by ion exchange chromatography. In addition to differences in subunit size and cellular compartmentalization of the isoenzymes, differences have been reported in their activity and susceptibility to inhibition. The structural basis of these isoenzymes is unclear; we attempted to further define their functional characteristics and structural identity. First, we measured respective enzymatic activity using a panel of substrates; MPO I was found to have lower activity with some substrates (pyrogallol, guaiacol, potassium iodide [KI]), but similar activity to the other isoenzymes with 4-aminoantipyrine. These studies confirm that MPO I is enzymatically distinct from MPO II and MPO III. Next, we examined the structural basis of these differences by evaluating the iron-containing prosthetic group in each form using electron paramagnetic resonance (EPR) and determination of the pyridine hemochrome. No significant difference between the isoenzymes was noted in these parameters, suggesting that the prosthetic group is the same in each protein. The cause for any difference in enzymatic activity must lie then in variations extrinsic to the heme, and based on previous studies of the gene and protein analysis, the posttranslational modification of MPO must account for these isoenzymatic species.

Research note: sleep problems of normal Chinese adolescents

Eight hundred and forty-six Chinese adolescents were surveyed concerning sleep behaviours including insomnia, nightmares, somniloquism, somnambulism, bruxism, and enuresis. Bruxism was reported most frequently (22%) followed by somniloquism (17%) and insomnia (14.9%). Subjects were compared by sex, age, and rearing by parents or parent surrogates. Cross cultural comparisons and the possible significance of findings are discussed.

Patterns of psychiatric consultation in a Chinese general hospital

The authors conducted a study of psychiatric consultation in a Chinese general hospital. Seventy-five inpatients (0.74% of the patients in the hospital) were referred by different services over a 1-year period. Internal medicine referred the most patients, and organic brain syndromes were the most common diagnoses. Depression was not a frequent diagnosis, but neurasthenia was a fairly common one. None of the referred patients had a diagnosis of alcoholism, drug abuse, or personality disorder. The authors compare these data with those of Western studies and discuss the possible factors influencing psychiatric consultation in China.