Exploration of beauvericin's toxic effects and mechanisms in human astrocytes and N-acetylcysteine's protective role

Beauvericin (BEA) is a newly identified mycotoxin produced by various Fusarium species, and its contamination in food and animal feed is widespread globally. This mycotoxin demonstrates cytotoxic effects by inducing oxidative stress in multiple models. Furthermore, evidence indicates that BEA possesses diverse toxic activities, making it a promising candidate for toxicological research. Recent studies have highlighted the ability of BEA to traverse the blood-brain barrier, suggesting its potential neurotoxicity. However, limited information is available regarding the neurotoxic effects of BEA on human astrocytes. Therefore, this study aimed to assess the neurotoxic effects of BEA on the Gibco® Human Astrocyte (GHA) cell line and elucidate the underlying mechanisms. Additionally, the study aimed to investigate the protective effects of the antioxidant N-acetylcysteine (NAC) against BEA-induced toxicity. The data show that exposure to BEA within the 2.5-15 μM concentration range resulted in concentration-dependent cytotoxicity. BEA-treated cells exhibited significantly increased levels of reactive oxygen species (ROS), while intracellular glutathione (GSH) content was significantly reduced. Western blot analysis of cells treated with BEA revealed altered protein levels of Bax, cleaved caspase-9, and caspase-3, along with an increased Bax/Bcl-2 ratio, indicating the induction of apoptosis. Additionally, BEA exposure triggered antioxidant responses, as evidenced by increased protein expression of Nrf2, HO-1, and NQO1. Significantly, pretreatment with NAC partially attenuated the significant toxic effects of BEA. In conclusion, our findings suggest that BEA-induced cytotoxicity in GHA cells involves oxidative stress-associated apoptosis. Furthermore, NAC demonstrates potential as a protective agent against BEA-induced oxidative damage.

Microglial activation and toll-like receptor 4-Dependent regulation of angiotensin II type I receptor-mu-opioid receptor 1 heterodimerization and hypertension in fructose-fed rats

Our previous study reported that the heterodimer of Angiotensin II Type I Receptor (AT1R) and Mu-Opioid Receptor 1 (MOR1) involves Nitric Oxide (NO) reduction which leads to elevation of blood pressure. Secondly, we showed that Toll-like Receptor 4 (TLR4) may be involved in the heterodimerization of AT1R and MOR1 in the brainstem Nucleus Tractus Solitarii (NTS), which regulates systemic blood pressure and gastric nitric oxide through the insulin pathway. Here, we investigated the role of microglial activation and TLR4 in the heterodimerization of AT1R and MOR1. Hypertensive rats were established after four weeks of fructose consumption. SBP of rats was measured using non-invasive blood pressure method. PLA technique was utilized to determine protein-protein interaction in the nucleus tractus solitarii. Results showed that the level of MOR-1 and AT1R was induced significantly in the fructose group compared with control. PLA signal potentially showed that AT1R and MOR1 were formed in the nucleus tractus solitarii after fructose consumption. Meanwhile, the innate immune cell in the CNS microglia was observed in the nucleus tractus solitarii using biomarkers and was activated. TLR4 inhibitor CLI-095, was administered to animals to suppress the neuroinflammation and microglial activation. CLI-095 treatment reduced the heterodimer formation of AT1R and MOR1 and restored nitric oxide production in the nucleus tractus solitarii. These findings imply that TLR4-primed neuroinflammation involves formation of heterodimers AT1R and MOR1 in the nucleus tractus solitarii which leads to increase in systemic blood pressure.

Attenuation of epithelial-mesenchymal transition via SGLT2 inhibition and diabetic cataract suppression by dapagliflozin nanoparticles treatment

AIMS

Chronic hyperglycemia triggers overproduction of AKR1B1 (aldo-keto reductase family 1 member B) and receptor for advanced glycation end product (RAGE), which causes epithelial-mesenchymal transition (EMT) in the lens epithelial cells (LECs) of diabetic mellitus (DM) cataracts. However, it is unclear whether EMT in LECs is related to abnormal increase of SGLT2. Sodium glucose cotransporter 2 (SGLT2) inhibitor, also known as dapagliflozin (Dapa) can be used to treat diabetes. Here, we examined how Dapa or nano eye-drops (DapaN) reduce EMT in LECs of DM cataracts. The nano eye-drop provides an ophthalmic treatment that suppressed diabetic cataract progression and improved potency with reduced side effects.

MAIN METHODS

SD rats were injected with streptozocin (STZ) (65 mg/kg, ip), nano-Dapa drops (0.456 mg/10 ml/eye) or Dapa (1.2 mg/kg/day) treatment for 6-12 weeks. Immunofluorescence staining was used for protein quantification of RAGE, SGLT2, N-cadherin and E-cadherin in the LECs of rats.

KEY FINDINGS

In this study, Dapa applies nanotechnology-based delivery system and it contains polyvinylpyrrolidone (PVP) and HPBCD. Dapa showed therapeutic effect on DM cataracts, wherein it targeted EMT biomarker, E-cadherin. The nano-Dapa drops or oral Dapa inhibited SGLT2, suppressed AKR1B1 expression, decreased AcSOD2- and RAGE-induced EMT in diabetic cataracts. Our findings suggest that nanotechnology-based Dapa eye drops (Dapa-PVP-HPBCD) can effectively improve solubility of Dapa in aqueous solution.

SIGNIFICANCE

Taken together, results suggest that the SGLT2-mediated DM cataract therapy may involve the AKR1B1-RAGE-AcSOD2-EMT pathway. The nano eye drops and Dapa show potential beneficial effects for cataract prevention. This study conveys new insights into cataract treatment and supplementation of nano-Dapa drops shows promising result in preventing diabetic cataracts.

Hyperlactatemia is associated with increased risks of long-term mortality and major adverse cardiovascular events in sepsis survivors

INTRODUCTION

Serum lactate is a potentially valuable biomarker for risk assessment for patients with sepsis, as hyperlactatemia is associated with elevated short-term mortality risks. However, the associations between hyperlactatemia and long-term clinical outcomes in sepsis survivors remain unknown. The objective of this study was to investigate whether hyperlactatemia at the time of hospitalisation for sepsis was associated with worse long-term clinical outcomes in sepsis survivors.

METHODS

In total, of 4983 sepsis survivors aged ≥ 20 years were enrolled in this study between January 1, 2012, and December 31, 2018. They were divided into low (≤18 mg/dL; n = 2698) and high (>18 mg/dL; n = 2285) lactate groups. The high lactate group was then matched 1:1 by propensity-score method to the low lactate group. The outcomes of interest were all-cause mortality, major adverse cardiac events (MACEs), ischaemic stroke, myocardial infarction, hospitalisation for heart failure, and end-stage renal disease.

RESULTS

After propensity score matching, the high lactate group had greater risks of all-cause mortality (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.41-1.67), MACEs (HR 1.53, 95% CI 1.29-1.81), ischaemic stroke (HR 1.47, 95% CI 1.19-1.81), myocardial infarction (HR 1.52, 95% CI 1.17-1.99), and end-stage renal disease (HR 1.42, 95% CI 1.16-1.72). Subgroup analyses stratified by baseline renal function revealed almost similarity across groups.

CONCLUSION

We found that hyperlactatemia is associated with long-term risks of mortality and MACEs in sepsis survivors. Physicians may consider more aggressive and prompter management of sepsis in patients who present with hyperlactatemia to improve long-term prognoses.

μ-Opioid Receptor-Mediated AT1R-TLR4 Crosstalk Promotes Microglial Activation to Modulate Blood Pressure Control in the Central Nervous System

Opioids, a kind of peptide hormone involved in the development of hypertension, cause systemic and cerebral inflammation, and affects regions of the brain that are important for blood pressure (BP) control. A cause-and-effect relationship exists between hypertension and inflammation; however, the role of blood pressure in cerebral inflammation is not clear. Evidence showed that AT1R and μOR heterodimers’ formation in the NTS might lead to the progression of hypertension. In this study, we investigated the formation of the μOR/AT1R heterodimer, determined its correlation with μORs level in the NTS, and explored the role of TLR4-dependent inflammation in the development of hypertension. Results showed that Ang II increased superoxide and Iba-1 (microgliosis marker: ionized calcium-binding adaptor molecule (1) levels in the NTS of spontaneously hypertensive rats (SHRs). The AT1R II inhibitor, losartan, significantly decreased BP and abolished superoxide, Iba-1, TLR4 expression induced by Ang II. Furthermore, losartan significantly increased nNsOS^S1416 phosphorylation. Administration of a μOR agonist or antagonist in the NTS of WKY and SHRs increased endogenous μ-opioids, triggered the formation of μOR/AT1R heterodimers and the TLR4-dependent inflammatory pathway, and attenuated the effect of depressor nitric oxide (NO). These results imply an important link between neurotoxicity and superoxides wherein abnormal increases in NTS endogenous μ-opioids promote the interaction between Ang II and μOR, the binding of Ang II to AT1R, and the activation of microglia. In addition, the interaction between Ang II and μOR enhanced the formation of the AT1R and μOR heterodimers, and inactivated nNOS-derived NO, leading to the development of progressive hypertension.

Exercise prevents the impairment of learning and memory in prenatally phthalate-exposed male rats by improving the expression of plasticity-related proteins

Regular exercise has been identified to facilitate neuroplasticity that maximize functional outcome after brain injuries. Brain-derived neurotrophic factor (BDNF) has emerged as a key facilitator of neuroplasticity after exercise. The activity-regulated cytoskeleton associated protein (Arc) is induced by BDNF and N-methyl-d-aspartic acid receptor (NMDAR), contributing to functional modification of neuroplasticity in the hippocampus. Meanwhile, early-life exposure to neuroendocrine disruptor di-(2-ethylhexyl)-phthalate (DEHP) is a risk factor for behavioral deficits, but the mechanisms responsible for DEHP-induced neurotoxicity are not well understood. The purpose of this study is to investigate whether hippocampal Arc expression is impaired by DEHP exposure and to examine the protective role of exercise in the prenatally DEHP-exposed male rats. Sprague Dawley dams were fed with vehicle or DEHP during gestation. The male offspring were trained to treadmill running for 5 weeks followed by examination of behavioral and biochemical outcomes. The results showed that DEHP-exposed rats exhibited impairment of spatial learning and memory as well as down-regulations of BDNF, NMDAR, Arc, and synaptophysin. Importantly, aerobic exercise during childhood-adolescence prevented the impairment of learning and memory by recovering the expressions of BDNF, NMDAR, Arc, and synaptophysin. These findings suggest that exercise may provide beneficial effects on ameliorating the impairment of neuroplasticity in the prenatally DEHP-exposed male rats at late adolescence.

Mechanism of a methylxanthine drug theophylline-induced Ca2+ signaling and cytotoxicity in AML12 mouse hepatocytes

Theophylline is a methylxanthine drug used in therapy for respiratory diseases. However, the impact of theophylline on Ca²⁺ signaling has not been explored in liver cells. This study examined whether theophylline affected Ca²⁺ homeostasis and its related cytotoxicity in AML12 mouse hepatocytes. Cell viability was measured by the cell viability reagent (WST-1). Cytosolic Ca²⁺ concentration ([Ca²⁺]_i) was measured by the Ca²⁺-sensitive fluorescent dye fura-2. Theophylline (25-125 μM) induced [Ca²⁺]_i rises and cause cytotoxicity in AML12 cells. This cytotoxic response was reversed by chelation of cytosolic Ca²⁺ with BAPTA/AM. In Ca²⁺-free medium, treatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin abolished theophylline-induced [Ca²⁺]_i rises. Conversely, treatment with theophylline also abolished thapsigargin-induced [Ca²⁺]_i rises. However, inhibition of PLC failed to alter theophylline-evoked [Ca²⁺]_i rises. In Ca²⁺-containing medium, modulators of store-operated Ca²⁺ channels inhibited 30% of the [Ca²⁺]_i rises, whereas the PKC modulators had no effect. Furthermore, theophylline-induced Ca²⁺ influx was confirmed by Mn²⁺-induced quench of fura-2 fluorescence. Together, in AML12 cells, theophylline caused Ca²⁺-associated cytotoxicity and induced Ca²⁺ entry through PLC-independent Ca²⁺ release from the endoplasmic reticulum and PKC-insensitive store-operated Ca²⁺ channels. BAPTA-AM with its protective effects may be a potential compound for prevention of theophylline-induced cytotoxicity.

CX3CR1-microglia mediates neuroinflammation and blood pressure regulation in the nucleus tractus solitarii of fructose-induced hypertensive rats

BACKGROUND

Inflammation is a common pathophysiological trait found in both hypertension and cardiac vascular disease. Recent evidence indicates that fractalkine (FKN) and its receptor CX3CR1 have been linked to inflammatory response in the brain of hypertensive animal models. Here, we investigated the role of CX3CR1-microglia in nitric oxide (NO) generation during chronic inflammation and systemic blood pressure recovery in the nucleus tractus solitarii (NTS).

METHODS

The hypertensive rat model was used to study the role of CX3CR1-microglia in NTS inflammation following hypertension induction by oral administration of 10% fructose water. The systolic blood pressure was measured by tail-cuff method of non-invasive blood pressure. The CX3CR1 inhibitor AZD8797 was administered intracerebroventricularly (ICV) in the fructose-induced hypertensive rat. Using immunoblotting, we studied the nitric oxide synthase signaling pathway, NO concentration, and the levels of FKN and CX3CR1, and pro-inflammatory cytokines were analyzed by immunohistochemistry staining.

RESULTS

The level of pro-inflammatory cytokines IL-1β, IL-6, TNF-α, FKN, and CX3CR1 were elevated two weeks after fructose feeding. AZD8797 inhibited CX3CR1-microglia, which improved the regulation of systemic blood pressure and NO generation in the NTS. We also found that IL-1β, IL-6, and TNF-α levels were recovered by AZD8797 addition.

CONCLUSION

We conclude that CX3CR1-microglia represses the nNOS signaling pathway and promotes chronic inflammation in fructose-induced hypertension. Collectively, our results reveal the role of chemokines such as IL-1β, IL-6, and TNF-α in NTS neuroinflammation with the involvement of FKN and CX3CR1.

Exploring the impact of a naturally occurring sapogenin diosgenin on underlying mechanisms of Ca2+ movement and cytotoxicity in human prostate cancer cells

Literature has shown that diosgenin, a naturally occurring sapogenin, inducedcytotoxic effects in many cancer models. This study investigated the effect of diosgenin on intracellular Ca²⁺ concentration ([Ca²⁺ ]i) and cytotoxicity in PC3 human prostate cancer cells. Diosgenin (250-1000 μM) caused [Ca²⁺ ]i rises which was reduced by Ca²⁺ removal. Treatment with thapsigargin eliminated diosgenin-induced [Ca²⁺ ]i increases. In contrast, incubation with diosgeninabolished thapsigargin-caused [Ca²⁺ ]i increases. Suppression of phospholipase C with U73122 eliminated diosgenin-caused [Ca²⁺ ]i increases. Diosgenin evoked Mn²⁺ influx suggesting that diosgenin induced Ca²⁺ entry. Diosgenin-induced Ca²⁺ influx was suppressed by PMA, GF109203X, and nifedipine, econazole, or SKF96365. Diosgenin (250-600 μM) concentration-dependently decreased cell viability. However, diosgenin-induced cytotoxicity was not reversed by chelation of cytosolic Ca²⁺ with BAPTA/AM. Together, diosgenin evoked [Ca²⁺ ]i increases via Ca²⁺ release and Ca²⁺ influx, and caused Ca²⁺ -non-associated deathin PC3 cells. These findings reveal a newtherapeutic potential of diosgenin for human prostate cancer.

Mechanisms underlying the effect of an oral antihyperglycaemic agent glyburide on calcium ion (Ca2+ ) movement and its related cytotoxicity in prostate cancer cells

Glyburide is an agent commonly used to treat type 2 diabetes and also affects various physiological responses in different models. However, the effect of glyburide on Ca²⁺ movement and its related cytotoxicity in prostate cancer cells is unclear. This study examined whether glyburide altered Ca²⁺ signalling and viability in PC3 human prostate cancer cells and investigated those underlying mechanisms. Intracellular Ca²⁺ concentrations ([Ca²⁺ ]_i ) in suspended cells were measured by using the fluorescent Ca²⁺ -sensitive dye fura-2. Cell viability was examined by WST-1 assay. Glyburide at concentrations of 100-1000 μM induced [Ca²⁺ ]_i rises. Ca²⁺ removal reduced the signal by approximately 60%. In Ca²⁺ -containing medium, glyburide-induced Ca²⁺ entry was inhibited by 60% by protein kinase C (PKC) activator (phorbol 12-myristate 13 acetate, PMA) and inhibitor (GF109203X), and modulators of store-operated Ca²⁺ channels (nifedipine, econazole and SKF96365). Furthermore, glyburide induced Mn²⁺ influx suggesting of Ca²⁺ entry. In Ca²⁺ -free medium, inhibition of phospholipase C (PLC) with U73122 significantly inhibited glyburide-induced [Ca²⁺ ]_i rises. Treatment with the endoplasmic reticulum (ER) Ca²⁺ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) abolished glyburide-evoked [Ca²⁺ ]_i rises. Conversely, treatment with glyburide abolished BHQ-evoked [Ca²⁺ ]_i rises. Glyburide at 100-500 μM decreased cell viability, which was not reversed by pretreatment with the Ca²⁺ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Together, in PC3 cells, glyburide induced [Ca²⁺ ]_i rises by Ca²⁺ entry via PKC-sensitive store-operated Ca²⁺ channels and Ca²⁺ release from the ER in a PLC-dependent manner. Glyburide also caused Ca²⁺ -independent cell death. This study suggests that glyburide could serve as a potential agent for treatment of prostate cancer.

Dapagliflozin Prevents NOX- and SGLT2-Dependent Oxidative Stress in Lens Cells Exposed to Fructose-Induced Diabetes Mellitus

Purpose: Cataracts in patients with diabetes mellitus (DM) are a major cause of blindness in developed and developing countries. This study aims to examine whether the generation of reactive oxygen species (ROS) via the increased expression of glucose transporters (GLUTs) and the receptor for advanced glycation end products (RAGE) influences the cataract development in DM. Methods: Lens epithelial cells (LECs) were isolated during cataract surgery from patients without DM or with DM, but without diabetic retinopathy. In a rat model, fructose (10% fructose, 8 or 12 weeks) with or without dapagliflozin (1.2 mg/day, 2 weeks) treatment did induce DM, as verified by blood pressure and serum parameter measurements. Immunofluorescence stainings and immunoblottings were used to quantify the protein levels. Endogenous O₂˙¯ production in the LECs was determined in vivo with dihydroethidium stainings. Results: We investigated that GLUT levels in LECs differed significantly, thus leading to the direct enhancement of RAGE-associated superoxide generation in DM patients with cataracts. Superoxide production was significantly higher in LECs from rats with fructose-induced type 2 DM, whereas treatment with the sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin prevented this effect in fructose-fed rats. Protein expression levels of the sodium/glucose cotransporter 2 (SGLT2), GLUT1, GLUT5, the nicotinamide adenine dinucleotide phosphate reduced form (NADPH) oxidase subunit p67-phox, NOX2/4 and RAGE were upregulated in fructose-fed animals, whereas dapagliflozin treatment reversed these effects. Conclusions: In rats with fructose-induced DM, dapagliflozin downregulates RAGE-induced NADPH oxidase expression in LECs via the inactivation of GLUTs and a reduction in ROS generation. These novel findings suggest that the SGLT2 inhibitor dapagliflozin may be a candidate for the pharmacological prevention of cataracts in patients with DM.

Antihypertensive Potential of Coenzyme Q10 via Free Radical Scavenging and Enhanced Akt-nNOS Signaling in the Nucleus Tractus Solitarii in Rats

SCOPE

In the Natural Medicines database, coenzyme Q10 (CoQ10) is classified as possibly effective for the treatment of hypertension. Patients with hypertension frequently have a significant deficiency of the antioxidant CoQ10. Furthermore, reactive oxygen species are overproduced in the nucleus tractus solitarii (NTS) during the cardiovascular regulation of hypertension in vivo. However, the molecular mechanisms by which CoQ10 modulates cardiovascular functions in the NTS are unclear. In this study, the effects of CoQ10 on superoxide generation, downstream NO signaling in the NTS, and blood pressure were evaluated in rats with fructose-induced hypertension.

METHODS AND RESULTS

Treatment with oral CoQ10 for 4 weeks abolished nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) activation, decreased p38 phosphorylation, and increased superoxide dismutase 2 production in the NTS of fructose-fed rats. The serum levels of uric acid decrease in response to CoQ10 treatment in fructose-fed rats. Oral CoQ10 reduced blood pressure by inducing Akt and nNOS phosphorylation in NTS of fructose-induced hypertensive rats.

CONCLUSION

Oral CoQ10 decreases blood pressure by negatively regulating fructose-induced NADPH oxidase levels, abolishing ROS generation, reducing p38 phosphorylation, and enhancing the Akt-nNOS pathway in the NTS. These results support the beneficial effects of CoQ10 in oxidative stressassociated hypertension.

Effect of Resveratrol on Reactive Oxygen Species-Induced Cognitive Impairment in Rats with Angiotensin II-Induced Early Alzheimer's Disease †

Recent studies have indicated that several anti-hypertensive drugs may delay the development and progression of Alzheimer’s disease (AD). However, the relationships among AD, hypertension, and oxidative stress remain to be elucidated. Here, we aimed to determine whether reactive oxygen species (ROS) reduction by resveratrol in the brain leads to cognitive impairment reduction in rats with angiotensin II (Ang-II)-induced early AD. Male Wistar Kyoto (WKY) rats with Ang-II-induced AD were treated with losartan or resveratrol for two weeks. Our results show decreased blood pressure, increased hippocampal brain-derived neurotrophic factor (BDNF) level, and decreased nucleus tractus solitarius (NTS) ROS production in the Ang-II groups with losartan (10 mg/kg), or resveratrol (10 mg/kg/day) treatment. Furthermore, losartan inhibition of hippocampal Tau^T231 phosphorylation activated Akt^S473 phosphorylation, and significantly abolished Ang-II-induced Aβ precursors, active caspase 3, and glycogen synthase kinase 3β (GSK-3β)^Y216 expressions. Consistently, resveratrol showed similar effects compared to losartan. Both losartan and resveratrol restored hippocampal-dependent contextual memory by NADPH oxidase 2 (NOX2) deletion and superoxide dismutase 2 (SOD2) elevation. Our results suggest that both losartan and resveratrol exert neuroprotective effects against memory impairment and hippocampal damage by oxidative stress reduction in early stage AD rat model. These novel findings indicate that resveratrol may represent a pharmacological option similar to losartan for patients with hypertension at risk of AD during old age.

Resveratrol regulates blood pressure by enhancing AMPK signaling to downregulate a Rac1-derived NADPH oxidase in the central nervous system

Resveratrol is a polyphenol with pleiotropic effects against oxidative damage that has been widely implicated in lowering hypertension risk. The purpose of this study was to determine whether improve nitric oxide (NO) release in the brain, either through the activation of AMP-activated protein kinase (AMPK) or reduced Ras-related C3 botulinum toxin substrate 1 (Rac1)-induced reactive oxygen species (ROS) generation, thereby reducing blood pressure (BP) in rats with fructose-induced hypertension. The rats were fed with 10% fructose or Crestor (rosuvastatin; 1.5 mg·kg−1·day−1) and resveratrol (10 mg·kg−1·day−1) treatment for 1 wk, then the systolic blood pressure of the rats was measured by tail-cuff method. Endogenous in vivo superoxide radical production in the nucleus tractus solitarii (NTS) was determined with dihydroethidium. Immunoblotting analyses were used to quantify protein expression levels. Oral resveratrol treatment for 1 wk decreased BP and increased NO production in the NTS of fructose-fed rats but not in the control Wistar-Kyoto rats. The effect of Crestor is opposite that of resveratrol. Fructose induced hypertension by inactivating AMPK, which in turn enhanced the generation of ROS and reduced manganese superoxide dismutase by increasing the activity of Rac1-induced NADPH oxidase, abolishing the activity of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) and ribosomal protein S6 kinase (RSK) and neuronal nitric oxide synthase (nNOS) phosphorylation signaling pathway in the brain. However, resveratrol had the opposite effect in the fructose-fed rats. Overall, we show that the resveratrol decreased BP better than Crestor, abolished ROS generation, and enhanced the ERK1/2-RSK-nNOS pathway by activating AMPK to downregulate Rac1-induced NADPH oxidase levels in the NTS during oxidative stress–associated hypertension.

NEW & NOTEWORTHY 1) Evidence showed that the Ras-related C3 botulinum toxin substrate 1 (Rac1) augmented by Crestor (rosuvastatin) did not result in a significant change in blood pressure (BP) in fructose-induced hypertension. 2) Fructose induced hypertension by inactivating AMP-activated protein kinase (AMPK), which in turn enhanced the generation of reactive oxygen species (ROS) and reduced manganese superoxide dismutase in the brain. 3) Resveratrol decreased BP better than Crestor, abolished ROS generation, and enhanced the ERK1/2-ribosomal protein S6 kinase-neuronal nitric oxide synthase pathway by activating AMPK to negatively regulate Rac1-induced NADPH oxidase levels in the nucleus tractus solitarii during oxidative stress–associated hypertension.

[Implement of multimodal navigation-based virtual reality in the needle biopsy of intracranial eloquent lesions]

Objective: To investigate the clinical value of multimodal navigation-based virtual reality (MNVR) in the needle biopsy of intracranial eloquent lesions. Methods: From January 2016 to January 2017, 20 patients with intracranial deep-seated lesions involving eloquent brain areas underwent MNVR-aided needle biopsy at Department of Neurosurgery, People's Liberation Army General Hospital. Preoperatively, MNVR was used to propose and revise the biopsy planning. Intraoperatively, navigation helped trajectory avoid the eloquent structures. Intraoperative MRI (iMRI) was performed to prove the biopsy accuracy and detect the intraoperative complications. Perioperative neurological status, iMRI findings, intraoprative complications, surgical outcome and pathological diagnosis were recorded. Wilcoxon rank-sum test was conducted to compare the preoperative and postoperative neurological scores. Results: MNVR helped revised 45%(9/20) initial biopsy trajectories, which would probably injury the nearby eloquent structures. Navigation helped biopsy trajectories spare the eloquent structures during the operation. No statistical difference was found between postoperative and preoperative neurological status, despite all the lesions were adjacent to eloquent areas. Additionally, 20 patients totally received 21 iMRI scanning. iMRI helped revise incorrect biopsy site in one case and detected intraoperative hemorrhage in another case, both of cases were treated immediately and effectively. No MNVR related adverse events and complications occurred. Conclusions: MNVR-aided needle biopsy of intracranial eloquent lesions is a safe, novel and efficient biopsy modality. This technique is helpful to reduce the incidence of surgery related neurological deficits.

Fructose induced neurogenic hypertension mediated by overactivation of p38 MAPK to impair insulin signaling transduction caused central insulin resistance

Type 2 diabetes are at a high risk of complications related to hypertension, and reports have indicated that insulin levels may be associated with blood pressure (BP). Fructose intake has recently been reported to promote insulin resistance and superoxide formation. The aim of this study is to investigate whether fructose intake can enhance superoxide generation and impair insulin signaling in the NTS and subsequently elevate BP in rats with fructose-induced hypertension. Treatment with fructose for 4 weeks increased the BP, serum fasting insulin, glucose, homeostatic model assessment-insulin resistance, and triglyceride levels and reduced the serum direct high-density lipoprotein level in the fructose group. The Tempol treatment recovered the fructose-induced decrease in nitric oxide production in the NTS. Immunoblotting and immunofluorescence analyses further showed that fructose increased the p38- and fructose-induced phosphorylation of insulin receptor substrate 1 (IRS1^S307) and suppressed Akt^S473 and neuronal nitric oxide synthase phosphorylation. Similarly, fructose was able to impair insulin sensitivity and increase insulin levels in the NTS. Fructose intake also increased the production of superoxide in the NTS. The results of this study suggest that fructose might induce central insulin resistance and elevate BP by enhancing superoxide production and activating p38 phosphorylation in the NTS.

Renal Denervation Improves the Baroreflex and GABA System in Chronic Kidney Disease-induced Hypertension

Hypertensive rats with chronic kidney disease (CKD) exhibit enhanced gamma-aminobutyric acid (GABA)_B receptor function and regulation within the nucleus tractus solitarii (NTS). For CKD with hypertension, renal denervation (RD) interrupts the afferent renal sympathetic nerves, which are connecting to the NTS. The objective of the present study was to investigate how RD improves CKD-induced hypertension. Rats underwent 5/6 nephrectomy for 8 weeks, which induced CKD and hypertension. RD was induced by applying phenol to surround the renal artery in CKD. RD improved blood pressure (BP) by lowering sympathetic nerve activity and markedly restored the baroreflex response in CKD. The GABA_B receptor expression was increased in the NTS of CKD; moreover, the central GABA levels were reduced in the cerebrospinal fluid, and the peripheral GABA levels were increased in the serum. RD restored the glutamic acid decarboxylase activity in the NTS in CKD, similar to the effect observed for central treatment with baclofen, and the systemic administration of gabapentin reduced BP. RD slightly improved renal function and cardiac load in CKD. RD may improve CKD-induced hypertension by modulating the baroreflex response, improving GABA system dysfunction and preventing the development and reducing the severity of cardiorenal syndrome type 4 in CKD rats.

Resveratrol Inhibition of Rac1-Derived Reactive Oxygen Species by AMPK Decreases Blood Pressure in a Fructose-Induced Rat Model of Hypertension

Recent studies have reported that the activation of AMP-activated protein kinase (AMPK) suppressed oxidative stress. The aim of this study was to examine whether the activation of AMPK in the brain decreased Rac1-induced ROS generation, thereby reducing blood pressure (BP) in rats with fructose-induced hypertension. The inhibition of ROS by treatment with an AMPK activator (oral resveratrol, 10 mg/kg/day) for 1 week decreased the BP and increased the NO production in the rostral ventrolateral medulla (RVLM) of fructose-fed rats but not in control Wistar-Kyoto (WKY) rats. In addition, resveratrol treatment abolished the Rac1-induced increases in the activity of the NADPH oxidase subunits p22-phox and reduced the activity of SOD2, while treatment with an AMPK inhibitor (compound C, 40 μM/day) had the opposite effect, in the fructose-fed rats. Interestingly, the activation of AMPK abolished Rac1 activation and decreased BP by inducing the activities of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and ribosomal protein S6 kinase (RSK) and nNOS phosphorylation in the fructose-fed rats. We conclude that the activation of AMPK decreased BP, abolished ROS generation, and enhanced ERK1/2-RSK-nNOS pathway activity by negatively regulating Racl-induced NADPH oxidase levels in the RVLM during oxidative stress–associated hypertension.

Wnt Signaling Regulates Blood Pressure by Downregulating a GSK-3β-Mediated Pathway to Enhance Insulin Signaling in the Central Nervous System

Aberrant Wnt signaling appears to play an important role in the onset of diabetes. Moreover, the insulin signaling pathway is defective in the nucleus tractus solitarii (NTS) of spontaneously hypertensive rats (SHRs) and fructose-fed rats. Nevertheless, the relationships between Wnt signaling and the insulin pathway and the related modulation of blood pressure (BP) in the central nervous system have yet to be established. The aim of this study was to investigate the potential signaling pathways involved in Wnt-mediated BP regulation in the NTS. Pretreatment with the LDL receptor-related protein (LRP) antagonist Dickkopf-1 (DKK1) significantly attenuated the Wnt3a-induced depressor effect and nitric oxide production. Additionally, the inhibition of LRP6 activity using DKK1 significantly abolished Wnt3a-induced glycogen synthase kinase 3β (GSK-3β)(S9), extracellular signal-regulated kinases 1/2(T202/Y204), ribosomal protein S6 kinase(T359/S363), and Akt(S473) phosphorylation; and increased insulin receptor substrate 1 (IRS1)(S332) phosphorylation. GSK-3β was also found to bind directly to IRS1 and to induce the phosphorylation of IRS1 at serine 332 in the NTS. By contrast, administration of the GSK-3β inhibitor TWS119 into the brain decreased the BP of hypertensive rats by enhancing IRS1 activity. Taken together, these results suggest that the GSK-3β-IRS1 pathway may play a significant role in Wnt-mediated central BP regulation.

Synthesis and antimicrobial activity of 9-o-substituted palmatine derivatives

A series of new palmatine derivatives with alkyl or alkyl with N-heterocyclic structures were designed and synthesized at C-9-O according to the principle of association. These compounds were characterised by ¹H NMR, ¹³C NMR, ESI-MS and elemental analysis, and tested for their antimicrobial activity in vitro to evaluate structure-activity relationships. The results indicated that 9-O-substituted palmatine derivatives exhibit varying degrees of antimicrobial activity. Antibacterial activities of compounds (3a-f) against Gram +ve bacteria increased 2- to 64-fold than that of palmatine. The compounds (3a-f) possessed relatively weaker inhibitory effects against Gram −ve bacteria and fungi than that against Gram +ve bacteria. Antimicrobial activities of compounds (5a-e) are lower than that of compounds (3a-f). Compound 3d showed the highest antimicrobial activity of all the compounds. The LD₅₀ values of compounds (3a-f) decreased as the alkyl side chain was elongated. Compound 3f showed least toxicity.

GPCR dimerization in brainstem nuclei contributes to the development of hypertension

BACKGROUND AND PURPOSE

μ-Opioid receptors, pro-opiomelanocortin and pro-enkephalin are highly expressed in the nucleus tractus solitarii (NTS) and μ receptor agonists given to the NTS dose-dependently increased BP. However, the molecular mechanisms of this process remain unclear. In vitro, μ receptors heterodimerize with α2A -adrenoceptors. We hypothesized that α2A -adrenoceptor agonists would lose their depressor effects when their receptors heterodimerize in the NTS with μ receptors.

EXPERIMENTAL APPROACH

We microinjected μ-opioid agonists and antagonists into the NTS of rats and measured changes in BP. Formation of μ receptor/α2A -adrenoceptor heterodimers was assessed with immunofluorescence and co-immunoprecipitation methods, along with proximity ligation assays.

KEY RESULTS

Immunofluorescence staining revealed colocalization of α2A -adrenoceptors and μ receptors in NTS neurons. Co-immunoprecipitation revealed interactions between α2A -adrenoceptors and μ receptors. In situ proximity ligation assays confirmed the presence of μ receptor/α2A -adrenoceptor heterodimers in the NTS. Higher levels of endogenous endomorphin-1 and μ receptor/α2A -adrenoceptor heterodimers were found in the NTS of hypertensive rats, than in normotensive rats. Microinjection of the μ receptor agonist [D-Ala(2) , MePhe(4) , Gly(5) -ol]-enkephalin (DAMGO), but not that of the α2A -adrenoceptor agonist guanfacine, into the NTS of normotensive rats increased μ receptor/α2A -adrenoceptor heterodimer formation and BP elevation. The NO-dependent BP-lowering effect of α2A -adrenoceptor agonists was blunted following increased formation of μ receptor/α2A -adrenoceptor heterodimers in the NTS of hypertensive rats and DAMGO-treated normotensive rats.

CONCLUSIONS AND IMPLICATIONS

Increases in endogenous μ receptor agonists in the NTS induced μ receptor/α2A -adrenoceptor heterodimer formation and reduced the NO-dependent depressor effect of α2A -adrenoceptor agonists. This process could contribute to the pathogenesis of hypertension.

Resveratrol decreases fructose-induced oxidative stress, mediated by NADPH oxidase via an AMPK-dependent mechanism

BACKGROUND AND PURPOSE

Oxidative stress is an important pathogenic factor in the development of hypertension. Resveratrol, the main antioxidant in red wine, improves NO bioavailability and prevents cardiovascular disease. The aim of this study was to examine whether resveratrol decreases the generation of reactive oxygen species (ROS), thereby reducing BP in rats with fructose-induced hypertension.

EXPERIMENTAL APPROACH

Rats were fed 10% fructose with or without resveratrol (10 mg·kg(-1) ·day(-1) ) for 1 week or for 4 weeks with resveratrol treatment beginning at week 2; systolic BP (SBP) was measured by tail-cuff method. Endogenous in vivo O2 (-) production in the nucleus tractus solitarii (NTS) was determined with dihydroethidium. Real-time PCR and immunoblotting analyses were used to quantify RNA and protein expression levels.

KEY RESULTS

In fructose-fed rats, ROS levels in the NTS were higher, whereas the NO level was significantly decreased. Also, RNA and protein levels of NADPH oxidase subunits (p67, p22-phox) were elevated, superoxide dismutase 2 (SOD2) reduced and AMP-activated PK (AMPK) T172 phosphorylation levels in the NTS were lower in fructose-fed rats. Treatment with the AMPK activator resveratrol decreased levels of NADPH oxidase subunits and ROS, and increased NO and SOD2 levels in the NTS of fructose-fed rats. Administration of resveratrol, in combination with fructose at week 0 and later at week 2, significantly reduced the SBP of fructose-fed rats.

CONCLUSIONS AND IMPLICATIONS

Collectively, resveratrol decreased BP through the phosphorylation of AMPK, Akt and neuronal NOS in fructose-fed rats. These novel findings suggest that resveratrol may be a potential pharmacological candidate for the treatment of hypertension.

Simvastatin induces a central hypotensive effect via Ras-mediated signalling to cause eNOS up-regulation

BACKGROUND AND PURPOSE

Clinical studies indicate that statins have a BP-lowering effect in hypercholesterolemic individuals with hypertension. Specifically, statins modulate BP through the up-regulation of endothelial NOS (eNOS) activation in the brain. However, the signalling mechanisms through which statins enhance eNOS activation remain unclear. Therefore, we examined the possible signalling pathways involved in statin-mediated BP regulation in the nucleus tractus solitarii (NTS).

EXPERIMENTAL APPROACH

To investigate the involvement of Ras and other signalling pathways in simvastatin-induced effects on BP, BP and renal sympathetic nerve activity (RSNA) were determined in spontaneously hypertensive rats (SHRs) before and after i.c.v. administration of simvastatin in the absence and presence of a Ras-specific inhibitor (farnesyl thiosalicylic acid, FTS), a geranylgeranyltransferase inhibitor (GGTI-2133), a PI3K inhibitor (LY294002) or a MAPK-ERK kinase (MEK) inhibitor (PD98059).

KEY RESULTS

FTS significantly attenuated the decrease in BP and increased NO evoked by simvastatin and reversed the decrease in basal RSNA induced by simvastatin. Immunoblotting and pharmacological studies showed that inhibition of Ras activity by FTS significantly abolished simvastatin-induced phosphorylation of ERK1/2, ribosomal protein S6 kinase (RSK), Akt and decreased eNOS phosphorylation. Likewise, administration of Akt and ERK1/2 signalling inhibitors, LY294002 and PD98059, attenuated the reduction in BP evoked by simvastatin. Furthermore, i.c.v. simvastatin decreased Rac1 activation and the number of ROS-positive cells in the NTS.

CONCLUSIONS AND IMPLICATIONS

Simvastatin modulates central BP control in the NTS of SHRs by increasing Ras-mediated activation of the PI3K-Akt and ERK1/2-RSK signalling pathways, which then up-regulates eNOS activation.

Caffeine intake improves fructose-induced hypertension and insulin resistance by enhancing central insulin signaling

Recent clinical studies found that fructose intake leads to insulin resistance and hypertension. Fructose consumption promotes protein fructosylation and formation of superoxide. In a previous study, we revealed that inhibition of superoxide production in the nucleus tractus solitarii (NTS) reduces blood pressure. Caffeine displays significant antioxidant ability in protecting membranes against oxidative damage and can lower the risk of insulin resistance. However, the mechanism through which caffeine improves fructose-induced insulin resistance is unclear. The aim of this study was to investigate whether caffeine consumption can abolish superoxide generation to enhance insulin signaling in the NTS, thereby reducing blood pressure in rats with fructose-induced hypertension. Treatment with caffeine for 4 weeks decreased blood pressure, serum fasting glucose, insulin, homeostatic model assessment-insulin resistance, and triglyceride levels and increased the serum direct high-density lipoprotein level in fructose-fed rats but not in control rats. Caffeine treatment resulted in the recovery of fructose-induced decrease in nitric oxide production in the NTS. Immunoblotting and immunofluorescence analyses further showed that caffeine reduced the fructose-induced phosphorylation of insulin receptor substrate 1 (IRS1(S307)) and reversed Akt(S473) and neuronal nitric oxide synthase phosphorylation. Similarly, caffeine was able to improve insulin sensitivity and decrease insulin levels in the NTS evoked by fructose. Caffeine intake also reduced the production of superoxide and expression of receptor of advanced glycation end product in the NTS. These results suggest that caffeine may enhance insulin receptor substrate 1-phosphatidylinositol 3-kinase-Akt-neuronal nitric oxide synthase signaling to decrease blood pressure by abolishing superoxide production in the NTS.

Central nicotinic acetylcholine receptor involved in Ca(2+) -calmodulin-endothelial nitric oxide synthase pathway modulated hypotensive effects

BACKGROUND AND PURPOSE

Recent evidence has suggested that nicotine decreases blood pressure (BP) and heart rate (HR) in the nucleus tractus solitarii (NTS), indicating that nicotinic acetylcholine receptors (nAChRs) play an important role in BP control in the NTS. However, the signalling mechanisms involved in nAChR-mediated depressor effects in the NTS are unclear. Hence, the aim of this study was to investigate these signalling mechanisms.

EXPERIMENTAL APPROACH

Depressor responses to nicotine microinjected into the NTS of Wistar-Kyoto rats were elicited in the absence and presence of an antagonist of α7 nAChR, the calcium chelator ethylene glycol tetraacetic acid, a calmodulin-specific inhibitor, nitric oxide (NO) synthase (NOS) inhibitor, endothelial NOS (eNOS)-selective inhibitor or neuronal NOS (nNOS)-specific inhibitor.

KEY RESULTS

Microinjection of nicotine into the NTS produced a dose-dependent decrease in BP and HR, and increased nitrate levels. This depressor effect of nicotine was attenuated after pretreatment with a nAChR antagonist or blockers of the calmodulin-eNOS pathway. In contrast, N5-(1-Imino-3-butenyl)-L-ornithine (vinyl-L-NIO), nNOS-specific inhibitor, did not diminish these nicotine-mediated effects. Calmodulin was found to bind eNOS after nicotine injection into NTS. However, nicotine did not affect the eNOS phosphorylation level or eNOS upstream extracellular signal-regulated kinases (ERK)1/2 and Akt phosphorylation levels. Furthermore, pretreatment with an ERK1/2 or Akt inhibitor did not attenuate nicotine-induced depressor effects in the NTS.

CONCLUSIONS AND IMPLICATIONS

These results suggest that the nAChR-Ca(2+) -calmodulin-eNOS-NO signalling pathway, but not nNOS, plays a significant role in central BP regulation, and neither the ERK1/2 nor Akt signalling pathway are significantly involved in the activation of eNOS by nAChRs in the NTS.

Mediating roles of adherence attitude and patient education on antidepressant use in patients with depression

PURPOSE

The purpose of this study was to examine the roles of adherence attitude to antidepressants and patient education as mediators in mediating patients' attitudes toward antidepressant use.

DESIGN AND METHODS

A sample of 201 outpatients, 50 years of age or older, with major depressive disorder, completed a drug use questionnaire, attitudes toward and patient education about antidepressants questionnaire, and Adherence Attitude Inventory.

FINDINGS

Attitudes toward antidepressants were positively associated to antidepressant use, an association explained by the mediating variable, patient education about antidepressants. Adherence attitudes to antidepressants were a mediator that accounted to a significant degree for the causal relationship between attitudes toward antidepressants and antidepressant use.

PRACTICE IMPLICATIONS

Adequate patient education and an understanding of patients' adherence attitude to antidepressant use are needed in nursing practice to reduce patients' uncertainty about treatment and increase successful treatment.

First Report of Anthracnose of Digitaria sanguinalis Caused by Colletotrichum hanaui in China

Hairy crabgrass (Digitaria sanguinalis (L.) Scop.) is a troublesome weed in most agricultural crops worldwide. Considerable efforts are made to limit the invasiveness and impact of crabgrass on crop productivity, including evaluation of fungi as biocontrol agents (3). In September 2005, a severe disease was observed on crabgrass plants in Zhejiang Province. Leaves and stems of the affected plant showed small, water-soaked, brownish spots that rapidly turned into longitudinal elliptic or spindle-shaped lesions, 6.5 to 8 × 22 to 24 mm, with a brown outer edge and a gray sunken central area. Coalescence of large lesions gave rise to extensive rotting and necrosis, and the stems were broken when the lesions encircled. Acervuli with brown setae and falcate single-celled spores, typical of some Colletotrichum species (2), formed on the lesions at this late stage. One fungal isolate (Col-68) was obtained from symptomatic tissues on potato dextrose agar that led to white-to-gray appressed mycelium growth with orange conidial masses at 28°C in darkness. Setae were septate, dark brown, rounded and sometimes lobed at base, 32.0 to 116.5 × 3.2 to 6.0 μm, with apices acute. Hyphae were septate, hyaline, 1.0 to 6.5 μm, and sometimes guttulate. Conidia were falcate or fusiform, apices acute or obtuse, and 8.16 to 26.37 × 2.9 to 9.2 μm with an average of 18.15 × 5.65 μm. Hyphopodial appressoria were smooth, globose to prolate, ovoid or obovoid with obtuse or cylindrical apices, edges entire, and 4.17 to 14.25 × 3.77 to 8.94 μm with an average of 7.0 × 6.9 μm. The pathogen was initially identified as a Colletotrichum species based on morphology. Suspensions of 3-day-old spores collected from potato dextrose liquid cultures (10⁶ conidia per ml) were used to spray inoculate (15 ml per pot) three 9-cm-diameter pots of crabgrass seedlings at the three- to four-leaf growth stage. Another three pots of healthy crabgrass were simultaneously sprayed with sterilized distilled water without conidia, which served as noninoculated checks. The seedlings were kept at 25 to 28°C for 24 h under a polyethylene sheet cover in the greenhouse. Symptoms that developed in all inoculated seedlings were identical to those observed on the affected crabgrass in the field, meanwhile the seedlings inoculated with sterilized water had no significant symptoms, and the reisolated strain had the same characteristics as the original isolate. To diagnose the pathogen to the species level, three isolates were tested and an approximately 580-bp DNA amplicon of this isolate was amplified using the primers ITS1/ITS4. The sequence (GenBank Accession No. GQ456160) had 98% sequence identity with the sequences of Colletotrichum hanaui (GenBank Accession Nos. EU554101and EU554124), which is supported by phylogenetic analysis with bootstrap support. On the basis of the morphological, pathological characteristics, and phylogenetic tree, the isolated strain was identified as C. hanaui (1). To our knowledge, this is the first confirmed report of anthracnose of D. sanguinalis caused by newly described C. hanaui in China. References: (1) J. A. Crouch et al. Mycologia, 101:717, 2009. (2) B. C. Sutton. The Coelomycetes. CAB International Publishing, New York, 1980. (3) Y. Z. Zhu and S. Qiang. Chin. J. Biol. Control 20:206, 2004.

Attitudes toward and education about complementary and alternative medicine among adult patients with depression in Taiwan

AIMS

To investigate patients' attitudes toward complementary and alternative medicine, the education nurses provided about complementary and alternative medicine for treating depression and to test whether such education mediates the effect of complementary and alternative medicine use and attitudes toward complementary and alternative medicine.

BACKGROUND

Although we know that attitudes influence behaviour, very few studies simultaneously explore the relationship between attitudes, education and complementary and alternative medicine use.

DESIGN

Survey.

METHODS

This study was conducted as part of a larger survey, using face-to-face survey interviews with 206 adult patients aged 50 years or over and hospitalised in conventional hospitals in Taiwan for treatment of depression. The attitudes toward complementary and alternative medicine and patient education about complementary and alternative medicine instruments were specially developed for the study.

RESULTS

Participants expressed slightly favourable attitudes toward complementary and alternative medicine. Many participants (50%) expressed that they were willing to try any potential treatment for depression. They believed that complementary and alternative medicine helped them to feel better and to live a happier life. However, 66.5% of participants reported that they had inadequate knowledge of complementary and alternative medicine. Participants with a higher monthly income, longer depression duration and religious beliefs hold more positive attitudes toward complementary and alternative medicine. Most participants were not satisfied with the education they received about complementary and alternative medicine. Patient education about complementary and alternative medicine was found to be a mediator for the use of complementary and alternative medicine.

CONCLUSION

Patient education from nurses may predict patients' attitudes toward complementary and alternative medicine. Continuing nursing education is needed to enable nurses to respond knowledgeably to concerns patients may have about complementary and alternative medicine and treatment options.

RELEVANCE TO CLINICAL PRACTICE

This study highlights the potential role of patient education about complementary and alternative medicine as an effective way of adjusting patients' attitudes toward complementary and alternative medicine and to link both patients' preferences for complementary and alternative medicine and health professionals' concerns about the proper use of complementary and alternative medicine for depression management and adverse drug interactions.

Administration of donor-derived mesenchymal stem cells can prolong the survival of rat cardiac allograft

BACKGROUND

Mesenchymal stem cells (MSCs) are multipotent adult elements that have recently been shown to have profound immunomodulatory effects both in vitro and in vivo. Herein we have examined the impact of intravenous infusion of donor MSCs on the survival of transplanted hearts in a rat allograft model.

METHODS

Recipient Fisher344 rats were transplanted with hearts from inbred Wistar rats. Wistar rat MSCs were infused via the tail vein at designated intervals. In vitro mixed lymphocyte reaction (MLR) and cell-mediated lympholysis (CML) assays were performed to assess whether MSCs downregulated T-cell responses in vivo. Real-time polymerase chain reaction (PCR) was used to analyze the Th1/Th2 balance in MSC-treated and control groups.

RESULTS

The MSCs cultured in vitro exhibited multipotential for differentiation. Survival of the allografts was markedly prolonged by administration of MSCs compared with the controls, namely mean survivals of 12.4 vs 6.4 days, respectively. Real-time PCR showed a shift in the Th1/Th2 balance toward Th2. By MLR and CML assays, untreated control rats showed greater alloreactivity than did MSC-treated rats.

CONCLUSION

Our results indicated that MSCs suppressed allogeneic T-cell responses both in vitro and in vivo. Intravenous administration of MSCs prolonged the survival of transplanted hearts, possibly by induction of allograft tolerance through changing the Th1/Th2 balance.

Does postoperative pain induce emesis?

OBJECTIVE

The aim of this prospective, controlled study was to evaluate the risk factors for postoperative emesis in patients undergoing gynecologic surgery and receiving patient-controlled analgesia for three days.

METHODS

Six hundred twenty-five gynecologic patients with an American Society of Anesthesiologists physical status of I to III undergoing lower-abdominal surgeries were enrolled. A standard, general anesthetic technique was used. Postoperative pain was treated by a patient-controlled analgesia device with bolus intravenous doses of 1 mg morphine. For 3 days after surgery patients were assessed for occurrence of emesis, sedation, and pain intensity when at rest and during movement.

RESULTS

The incidence of emesis was 26% on postoperative day 1, 13% on day 2, and 4% on day 3. On all 3 days, patients' pain scores when at rest and when coughing were higher for those with emesis than for those without. During the first 2 postoperative days the patients with and those without emesis consumed similar amounts of morphine daily, but on the third day the patients with emesis consumed significantly more morphine than did those without emesis ( <0.05). Further logistic regression analysis showed that incident pain was the main risk factor for postoperative emesis on all 3 days.

CONCLUSIONS

The results suggested that postoperative pain was an associative risk factor to increase the incidence of emesis in these female patients.

Isolation and developmental expression of two nuclear receptors, MHR4 and betaFTZ-F1, in the tobacco hornworm, Manduca sexta

The cDNAs for two members of the nuclear receptor superfamily were isolated from the tobacco hornworm, Manduca sexta. The deduced amino acid sequence of MHR4 shows 93-95% identity in the DNA-binding domain and the first portion of the hinge (D) region with the germ cell nuclear factor (GCNF)-related factors (GRFs) of the silkworm, Bombyx mori, and the mealworm, Tenebrio molitor, and with a genomic sequence from the fruit fly, Drosophila melanogaster. Northern blot hybridization showed that a 7.5 kb MHR4 mRNA appeared in Manduca abdominal epidermis just as the ecdysteroid titer began to decline during the larval molt, disappeared about 12 h later, then transiently reappeared shortly before larval ecdysis. During the pupal and adult molts, a similar pattern of expression was seen (the very end of the adult molt was not studied). At peak times of expression in the epidermis, MHR4 mRNA was also present in fat body and the central nervous system (CNS). The deduced amino acid sequence of Manduca FTZ-F1 is 100% and 96% identical to that of B. mori and Drosophila betaFTZ-F1, respectively, in the DNA-binding domain and the adjacent hinge region including the FTZ-F1 box. Northern blot analysis showed that the >9.5 kb betaFTZ-F1 mRNA appeared in Manduca epidermis during the decline of the ecdysteroid titer in the larval, pupal and adult molts as the first peak of MHR4 mRNA declined, then it disappeared in the larval and pupal molts before the second peak of MHR4 appeared. betaFTZ-F1 mRNA was also found in fat body and the CNS at the time of peak expression in the epidermis during the larval and pupal molts. Both MHR4 and betaFTZ-F1 mRNAs were found in the testis during the onset of spermatogenesis in the prepupal period.

Carbon dioxide laser induced airway fire during larynx surgery: case report

The precision intrinsic hemostatic properties of the laser have led to its wide use in modern clinical medicine especially in microscopic airway surgery. However, the intense heat generated by the high energy density of the surgical laser can convert combustible tubes into veritable torches, cause catastrophic fires, and result in severe injury to the patient. This is of particular importance when high energy is used on the continuous mode or when the endotracheal tube is repeatedly hit by the laser at the same spot. Most reported laser-induced complications result from the laser beam inadvertently falling on the areas that are not intended to be exposed. We report a case of a trans-tracheostomy tube fire occurring during carbon dioxide (CO2) laser surgery. Aluminum-tape wrapping did not prevent this complication. It was found that the ignition of a trans-tracheostomy tube was caused by the laser striking an unprotected portion of the tube during resection of granuloma of the trachea.

Prolonged interference of patent blue on pulse oximetry readings

BACKGROUND

We evaluated the effect of intra-arterial injection of Patent Blue (PB) on pulse oximetry.

METHODS

Ten consecutive female patients who underwent intra-arterial insertion of catheter for chemotherapy were enrolled in this study. All patients received general anesthesia and ECG, pulse oximetry, and direct arterial blood pressure were monitored throughout the perioperative period. Baseline arterial blood saturation (SpO2), haemoglobin concentration (Hgb), estimated arterial saturation (SaO2), arterial oxygen partial pressure (PaO2) were obtained through arterial blood gas analysis, and true arterial saturation (ScoO2) through CO-Oximetry analysis. The subsequent values obtained at various points of time following the intra-arterial administration of PB were compared with the baseline data.

RESULTS

The SpO2 readings taken after intra-arterial injection of PB were significantly lower than the baseline reading. The extent of the reduction of SpO2 readings two hours after the administration of PB was relevant to the total accumulative dosage of PB (rs = -0.846, P < 0.05). However, the reduction of SpO2 bore no significant relation with Hgb concentration or with the ratio of PB dosage to Hgb concentration.

CONCLUSIONS

Intra-arterial administration of PB interferes with pulse oximetry readings and the effect lasts for a variable duration. The extent of desaturation may be related to the total accumulative dosage of intra-arterial PB injected.

Cutaneous blood vessels in scent pigs

The purpose of this study was to systematically provide anatomic data for flap research in plastic surgery on the cutaneous blood vessels. Seven scent pigs used in this study were killed anesthetically, and their carotid vessels were intubated and injected with a black liquid rubber. Twenty-four hours later, the integument of the scent pig was removed, and the perforating points of the cutaneous vessels were recorded. The different-sized pieces of integument became transparent. Part of this transparent skin tissue was cut into cross-sectional strips. There were three types of the cutaneous vascular source, the same as in humans. Six division levels of vessels in the skin were identified, which formed five vascular plexuses and two systems (the perforating vessel system and the cutaneous vessel system). There were two sets of vein systems: the concomitant vein and the oscillating vein; the latter can be divided into regular and irregular types. The structures of the perforating vessel system and the cutaneous vessel system were the morphological basis for choosing flaps. Two anatomic points have been emphasized: the preserved vascular plexus in thin flaps (not the subcutaneous vascular network reported previously) and the dependency of vascular structure on its location. Otherwise, this study has also provided two new kinds of flaps used in experimental study: the arterial loop flap and the intermuscular septal perforator flap. Although there were differences as well as similarities in skin vasculature between humans and the scent pig, the scent pig is still suitable for flap research.

109 cases of blepharoptosis treated by forked frontalis muscle aponeurosis procedure with long term follow-up

109 cases of severe or recurrent blepharoptosis have been treated with the forked frontalis muscle aponeurosis (FFMA) technique since 1989. In comparison with other frontalis muscle flap (FMF) protocols, this technique has three advantages: (i) no skin incision in the lower rim of the eyebrow; (ii) no incision in the frontalis muscle; and (iii) no dissection under the frontalis muscle. The FFMA is formed at the junction of the frontalis and orbicularis muscles. The 9-year follow-up shows that this is a highly effective procedure. The postoperative function of the frontalis muscle is good and the lack of damage has been confirmed by EMG. There are a few complications such as the sluggishness of the upper eyelid on downward gaze and the possibility of asymmetrical brow height in unilateral blepharoptosis. However, this technique may serve as the best choice in the treatment of severe or recurrent blepharoptosis.

Sequences of two cDNAs encoding silkworm homologues of Drosophila melanogaster squid gene

The squid (sqd) gene of Drosophila melanogaster encodes a few isoforms of a heterogeneous nuclear (hn) RNA-binding protein. We isolated two types of cDNAs coding for homologues of the Sqd protein from the silkworm Bombyx mori. The two predicted amino acid (aa) sequences are identical up to aa 280 and then diverge. The silkworm and fruit fly proteins share 80% homology in the RNA-binding motif region. These cDNAs detect 2.0-, 1.8- and 1-kb mRNAs in the middle and posterior silk glands.

Intermittent expression of BmFTZ-F1, a member of the nuclear hormone receptor superfamily during development of the silkworm Bombyx mori

BmFTZ-F1 is a sequence-specific DNA-binding factor in the silkworm Bombyx mori sharing similar biochemical characteristics with Drosophila FTZ-F1, a member of the nuclear hormone receptor superfamily. Using DNA sequence homology with FTZ-F1 and information on tryptic peptide sequences of BmFTZ-F1, we isolated a cDNA encoding for BmFTZ-F1. Amino acid sequences in the zinc finger DNA-binding region and the putative ligand-binding domain of BmFTZ-F1 showed strong similarity to not only FTZ-F1 but also its mammalian homologues, LRH-1, ELP, and Ad4BP, suggesting the importance of each region for the function of these proteins. Northern blot analyses of RNA isolated from the middle and posterior silk glands and fat bodies showed that a 6.1-kb BmFTZ-F1 mRNA is present in all tissues so far examined. Expression of BmFTZ-F1 mRNA is intermittent, being high during larval molting and both the larval-pupal and the pupal-adult transformations. Injection of 20-hydroxyecdysone at the third day of the 5th instar larvae induced BmFTZ-F1 mRNA in the posterior silk gland after 24 hr. When 5th instar silk glands were cultured in vitro, BmFTZ-F1 mRNA was induced by a 6-hr exposure to 20-hydroxyecdysone followed by 6 hr in hormone-free medium. These results suggest that BmFTZ-F1 is inducible by decline in the ecdysteroid titer and may play an important role in the development of the silkworm as a transcription factor.

A novel DNA-binding motif abuts the zinc finger domain of insect nuclear hormone receptor FTZ-F1 and mouse embryonal long terminal repeat-binding protein

Fruit fly FTZ-F1, silkworm BmFTZ-F1, and mouse embryonal long terminal repeat-binding protein are members of the nuclear hormone receptor superfamily, which recognizes the same sequence, 5'-PyCAAGGPyCPu-3'. Among these proteins, a 30-amino-acid basic region abutting the C-terminal end of the zinc finger motif, designated the FTZ-F1 box, is conserved. Gel mobility shift competition by various mutant peptides of the DNA-binding region revealed that the FTZ-F1 box as well as the zinc finger motif is involved in the high-affinity binding of FTZ-F1 to its target site. Using a gel mobility shift matrix competition assay, we demonstrated that the FTZ-F1 box governs the recognition of the first three bases, while the zinc finger region recognizes the remaining part of the binding sequence. We also showed that the DNA-binding region of FTZ-F1 recognizes and binds to DNA as a monomer. Occurrence of the FTZ-F1 box sequence in other members of the nuclear hormone receptor superfamily raises the possibility that these receptors constitute a unique subfamily which binds to DNA as a monomer.

Reconstruction of the external genitals and repair of skin defects of the perineal region using three types of lateral groin flap

Three types of lateral groin flap have been applied to reconstruct the external genitals and to repair skin defects in the perineal region. A single lateral groin flap was used to construct a vagina for 2 patients who had congenital absence of vagina. A composite flap containing iliac crest bone was applied to reconstruct the penis in 11 patients: 8 suffered traumatic amputation and 3 had congenital micropenis. A coaxial pedicle flap of the lateral groin and abdominal area was used to repair skin defects of the penis and scrotum after resection of the elephantiasis caused by recurrent erysipelas in 2 patients, and to relieve postburn scar contracture in the perineal region in another. Using this operative technique, 14 flaps survived completely with satisfactory results; 70% of one composite flap was lost as a result of hematoma. In the single-flap group, the distal portion (3 x 5 cm) of one flap necrosed and was resected and resurfaced with a free skin graft; the final result was good.

[Application of a lateral groin flap in reconstructive and reparative surgery of the perineal region]

Since March 1983, the authors have applied three types of lateral groin flap to reconstruct the external genitals and to repair skin defects in the perineal region in 16 cases. (1) A single lateral groin flap was used to construct vagina in two patients; (2) A composite flap containing iliac crest bone was applied to reconstruct penis in 11 cases; (3) A coaxial pedicle flap of the lateral groin and lower abdominal area was used to repair skin defects of the penis and scrotum in two cases, and to relieve postburn scar contracture in the perineal region in another. 14 flaps survive completely with satisfactory results. 70 per cent of 1 composite flap was lost because of hematoma. The distal portion (3 x 5 cm) of 1 single flap necrosed due to injury of the deep branch of SCIA during operation and resurfaced with a free skin graft, final result is fair.

The vascular microanatomy of skin territory of posterior forearm and its clinical application

We have undertaken a microanatomical study of a new donor site--the posterior forearm territory--on 43 cadaver arms. Two axial arteries were found, and both the fasciocutaneous flap and the fascial flap could be elevated with the two arteries on the posterior forearm. The posterior forearm flap was transferred to the hand to repair deformities of the wrist, the first web space, the dorsal hand, and the metacarpophalangeal joints in eight cases. The result was very satisfactory. The posterior forearm flap is near the hand, easy to perform, and reliable. It is a one-stage operation and does not sacrifice a main artery. In this article we demonstrate our own ideas about flap extension, which is valuable for clinical application.

One-stage reconstruction of the penis with composite iliac crest and lateral groin skin flap

We present a new method for a one-stage phalloplasty. In forming the penile body and its rigid supporting tissue, a composite flap, including the lateral groin skin flap (11 cm long and 10 cm wide) and the iliac crest bone in its entire length, is designed based on the superficial circumflex iliac artery and its accompanying veins. The urethra is constructed by one of two types of skin flap. When the skin of the scrotal septal area is good and hairless and the urethral opening is located at the pubic symphysis, a scrotal septal skin flap is used. When the scrotal skin cannot be used and the urethral opening is located in the scrotum or perineum, a superficial inferior epigastric vessel island skin flap can be selected. Since April 1983, the method has been used to reconstruct the penis in 4 patients. All operations were successful. The technique is described in detail and the advantages and disadvantages are stated.