Experimental studies on photocatalytic oxidation of nitric oxides using titanium dioxide

In order to remove nitric oxides （NO） from flue gas, experimental studies on the photocatalytic oxidation （PCO） of NO are carried out in an efficient laboratory-scale reactor. Nano-sized TiO2 particles loading on quartz sand are prepared and used as the photocatalyst. Effects of several key operating parameters on NO conversion are investigated, including operating temperature, NO inlet concentration, oxygen percentage, relative humidity and residence time. The results illustrate that the NO inlet concentration, the oxygen percentage and the relative humidity play an important role in the oxidation of NO. A lower NO inlet concentration and a higher oxygen percentage result in a higher NO conversion efficiency. When the relative humidity is 8%, the maximum value of NO conversion efficiency is achieved. In addition, the operating temperature and the residence time have a little effect on the conversion efficiency of NO.

Plasma endothelin and nitric oxide levels in patients with acute pancreatitis

Objective: To explore the changes of plasma endothelin(ET) and nitric oxide (NO) levels in patients with a-cute pancreatitis.Methods: The level of plasma ET was measured by ra-dioactive-immunoassay, and NO by spectrophotometry.Results: The levels of ET, NO and the ET/NO ratioin patients with severe acute pancreatitis(SAP) within24 hours in hospital were all significantly higher thanthose in other groups of patients [(176±8)pg/ml,(97±11) μmol/L, and 1.83±0.12, P<0.01]. Com-pared to healthy controls(N), the levels of ET and NOin patients without pancreatitis acute abdomen (NAP)and patients with mild acute pancreatitis (MAP) in-creased significantly (P<0.01). After appropriate treat-ment, the levels of ET and NO in the MAP groupwere lower (P<0.01). Compared with those beforetreatment, the levels of ET and NO in the SAP groupon the 3rd and 7th day in hospital dropped signifi-cantly(P<0.01).The ET/NO ratio on the 7th daywas also lower than that on admission (P<0.01).Conclusions: The malfunction of endothelial cells andthe increased ET/NO ratio may be related to the mecha-nism of pancreatic microcirculatory disturbance in pa-tients with SAP; early dynamic determination of theseparameters may help predict the prognosis of SAP.

Melatonin abates liver ischemia/reperfusion injury by improving the balance between nitric oxide and endothelin

BACKGROUND: Melatonin exerts complex physiological and pharmacological effects on multiple systems and organs. We hypothesized that melatonin might abate ischemia/ reperfusion (I/R) injury in the liver by inhibiting excessive oxidative stress and keeping nitric oxide (NO) from being scavenged by free radicals. The aim of the present study was to investigate whether melatonin protects the liver from I/R injury and, if so, by what underlying mechanism. METHODS: Under anesthesia, Wistar rats were intraperi- toneally injected with 20 mg/kg melatonin (dissolved in physiological saline containing 4% ethanol, Mel group), 4% alcohol (Alc group), or physiological saline (NS group). The artery, portal vein and bile duct of the left lobe of the liver were clamped for 60 minutes and then released. At different time points after I/R, the rats were sacrificed and blood samples were collected to measure the levels of serum alanine aminotransferase (ALT), lactic dehydrogenase (LDH), and NO. Hepatic tissue samples were collected for measuring endothelin expression by immunohistochemical staining and for routine morphological and histological examination. RESULTS: The levels of both ALT and LDH in the Mel group were significantly reduced for up to 24 hours after I/R compared with the Alc and NS groups (P<0.05). The levels of NO in the Mel group were significantly elevated for up to 12 hours after I/R relative to the NS group (P<0.05). The NO levels were also elevated at 0.5 and 6 hours after I/R in the Alc group (P<0.05). The immunohistochemical staining of hepatic tissue showedthat endothelin-positive cells were significantly fewer in the Mel group than in the Alc and NS groups at 6 hours after I/R (P<0.01). The necrosis of hepatocytes and the destruction of hepatic cords in the Alc and NS groups were greatly improved in Mel-treated rats, which is in concert with our functional data. CONCLUSIONS: Pretreatment with melatonin increased NO bioavailability and decreased endothelin expression, and consequently played a protective role in preserving both liver function and structure during ischemia and reperfusion injury.

Changes of nitric oxide and endothelin, thromboxane A2 and prostaglandin in cirrhotic patients undergoing liver transplantation

AIM： To investigate the perioperative changes of nitric oxide （NO） and endothelin （ET）, thromboxane A2 （TXA2） and prostaglandin （PGI2） during liver transplantation in end-stage liver disease patients. METHODS： Twenty-seven patients with end-stage cirrhosis undergoing liver transplantation were enrolled in this prospective study. Blood samples were obtained from superior vena at five different surgical stages. Plasma concentrations of nitrate and nitrite were determined to reflect plasma NO levels. Plasma levels of ET-1, 6-keto-PGF1 alpha and thromboxane B2 （TXB2）, the latter two being stable metabolites of PGI2 and TXA2 respectively, were measured.RESULTS： The NO level decreased significantly after vascular cross-clamping and increased significantly at 30 rain after reperfusion. While the ET levels at 30 rain after clamping and after reperfusion were significantly elevated. The ratio of NO/ET decreased significantly at 30 rain after vascular cross-clamping and at the end of surgery. The PGI2 level and the TXA2 during liver transplantation were significantly higher than the baseline level, but the ratio of TXA2/PGI2 decreased significantly at 30 rain after clamping. CONCLUSION： NO/ET and TXA2/PGI2 change during liver transplantation. Although the precise mechanism remains unknown, they may play a role in the pathobiology of a variety of liver transplant-relevant processes.

A Kinetic Study of Ozone and Nitric Oxides in Dielectric Barrier Discharges for O_2/NO_x Mixtures

A simple model is described to simulate kinetic processes in dielectric barrier dis-charges for O2/NOx mixtures. A threshold of ozone production found experimentally is confirmedby the calculations of this modeling, and the underiying chemical reaction mechanisms are dis-cussed. It is also found that the effects of diffusion processes in the period of the lifetime of Oatoms are not important to microdischarge channels with a large radius, i.e. larger than l50 μm.

Effect of Chanfukang(Chinese Medicine)on Endothelin and Nitric Oxide in Postpartum Cows with Qi Deficiency and Blood Stasis

[ Objective] To observe effect of Chanfukang on vascular endothelial cells of postpartum cows with Oi deficiency and Blood stasis, and to explore the treatment mechanism of Chanfukang. [Method] A total of 58 cows were assigned to four groups. The cows in group 1 and group 2 suffered from Qi deficiency and Blood stasis. The cows in group 1 were gavaged with Chanfukang （0.5 g/kg-BW, 5 d） at 12 h post partum, but the cows in group 2 were not treated. The cows in group 3 were healthy and gavaged with Chanfukang （0.4 g/kg.BW, 5 d） at 12 h post partum. Cows in group 4 were healthy control cows. The plasma endothelin （ET） concentration and serum nitric oxide （NO） concentration were determined before and after parturition, respectively. [ Result ] The plasma ET concentration and serum NO concentration were significantly higher in the cows with Qi deficiency and Blood stasis than in the healthy control cows （P 〈 0.05）. The NO concentration decreased on Day 10 post partum in the cows with Qi deficiency and Blood stasis, but it was still higher than that in the healthy control cows. After taking Chanfukang for 7 d, the ET concentration and NO concentration decreased, and no significant difference was found between the cows with Qi deficiency and Blood stasis treated with Chanfukang and the healthy control cows. [ Conclusion] Chanfukang may relieve Qi deficiency and Blood stasis of postpartum cows through decreasing plasma ET concentration and serum NO concentration.

Response of blood endothelin-1 and nitric oxide activity in duodenal ulcer patients undergoing Helicobacter pylori eradication

AIM: To investigate the effect of Helicobacter pylori eradication on endothelin-1 (ET-1) and nitric oxide (NO) in duodenal ulcer (DU) patients. METHODS: Sixty-six Hpylori-infected active DU patients were consecutively enrolled to receive one-week triple therapy (rabeprazole, amoxicillin and metronidazole) and then one-month rabeprazole therapy. They were asked back to determine ulcer and Hpylori status using endoscopy one month later. Thirty-seven healthy controls (H pylori +/-:17/20) were enrolled for comparison. Blood samples were collected in each visit to measure plasma ET-1 and nitrate/nitrite levels using an enzyme immunoassay kit. RESULTS: Sixty DU patients finished trial per protocol. The ulcer healing and Hpylori-eradication rates were 86.7% and 83.3%, respectively. Plasma ET-1 level in DU patients was higher than that of Hpylori-negative and positive controls (3.59±0.96 vs0.89±0.54 vs0.3±0.2 pg/mL,P<0.01), while nitrate/nitrite levels among them were also significantly different (8.55±0.71 vs5.27±0.68 vs 6.39±0.92 μmol/L, P<0.05). H pylori eradication diminished ET-1 levels (3.64±0.55 vs2.64±0.55 pg/mL, P<0.01) but elevated nitrate/ nitrite level (8.16±0.84 vs11.41±1.42 umol/L,P<0.05). CONCLUSION: Both plasma ET-1 and nitrate/nitrite levels increase in active DU patients. After an effective H pylori eradication, DU healing is associated with diminished blood ET-1 level and elevated nitrate/nitrite level.

The Effect of Nitric Oxide/Endothelins System on the Hepatic Ischemia/Reperfus ion Injury

The relationship between the hepatic ischemia/reperfusion (I/R) injury and the b alance of nitric oxide/endothelins (NO/ET) was studied. The changes of the ratio of NO/ET and the hepatic injury were observed in a rat hepatic I/R model pretre ated with several tool drugs. In the acute phase of hepatic I/R injury, the rati o of plasma NO/ET was reduced from 1.58 ± 0.20 to 0.29 ± 0.05 ( P < 0.01) a nd the hepatic damage deteriorated. NO donor L Arg and ET receptor antagonist T AK 044 cou ld alleviate the hepatic I/R injury to some degree, whereas NO synthase inhibito r L NAME aggravated the damage. It was concluded that the hepatic I/R injury mi ght be related with the disturbance of the NO/ET balance. Regulation of this bal ance might have an effect on the I/R injury.

Plasma endothelin-1 and nitric oxide correlate with ligustrazine alleviation of pulmonary artery hypertension in patients of chronic cor pulmonale from high altitude plateau during acute exacerbation

Objective To explore the mechanisms involved in the ligustrazine alleviation of the pulmonary artery hypertension(PAH) in patients of chronic obstructive pulmonary disease(COPD) associated with chronic cor pulmonale(CCP) during exacerbation.Methods Seventy patients of COPD and CCP with acute exacerbation were randomly and equally divided into control group and treatment group.The control group received standard treatment with antibiotics,antiasthmatic and expectorant medications,and oxygenation;and the ligustrazine treatment group received ligustrazine treatment(80 mg/d;i.v.;for 2 weeks) in addition to the standard treatment.Before and at the end of 2 week treatment,the clinic responses of the two regimens were evaluated,plasma levels of endothelin-1(ET-1) and nitric oxide(NO) were determined;arterial oxygen partial pressure(PaO_2),mean pulmonary arterial pressure(mPAP),outflow tract of right ventricle(RVOT),and internal diameter of right ventricle(RV) were measured.Results Good clinic benefits were achieved in both the standard and ligustrazine regimens,plasma level of ET-1,values of mPAP,RV and RVOT decreased significantly,plasma level of NO and PaO_2 values decreased(all P<0.01 vs pretreatment to all parameters).Compared with the control group,ligustrazine greatly enhanced the clinic efficacy from 77.1%to 97.1%(P<0.05),and also resulted in more significant changes of all these parameters(P<0.01 vs control group for all parameters).For both groups,the levels of plasma ET-1 were positively correlated with values of mPAP,RVOT,and RV(r = 0.710,0.853,and 0.766,respectively,all P = 0.000),and negatively correlated with plasma NO and PaO_2(r =- 0.823,and- 0.752,respectively,all P = 0.000).Conclusion Ligustrazine is effective in treating pulmonary artery hypertension during acute exacerbation of COPD and CCP in patients from the plateau area.The observed changes in the plasma levels of NO and ET-1 in response to ligustrazine treatment suggest that ligustrazine may act through the selective effect on pulmonary blood vessels to enhance the synthesis and release of NO and suppress those of ET-1 from lung vascular endothelial cells,thus reducing pulmonary artery pressure and decreasing pulmonary arterial hypertension.

Murine study of portal hypertension associated endothelin-1 hypo-response

AIM:To investigate endothelin-1 hypo-responsive associated with portal hypertension in order to improve patient treatment outcomes.METHODS:Wild type,e NOS-/-and i NOS-/-mice receivedpartial portal vein ligation surgery to induce portal hypertension or sham surgery.Development of portal hypertension was determined by measuring the splenic pulp pressure,abdominal aortic flow and portal systemic shunting.To measure splenic pulp pressure,a microtip pressure transducer was inserted into the spleen pulp.Abdominal aortic flow was measured by placing an ultrasonic Doppler flow probe around the abdominal aorta between the diaphragm and celiac artery.Portal systemic shunting was calculated by injection of fluorescent microspheres in to the splenic vein and determining the percentage accumulation of spheres in liver and pulmonary beds.Endothelin-1 hypo-response was evaluated by measuring the change in abdominal aortic flow in response to endothelin-1 intravenous administration.In addition,thoracic aorta endothelin-1contraction was measured in 5 mm isolated thoracic aorta rings ex-vivo using an ADI small vessel myograph.RESULTS:In wild type and i NOS-/-mice splenic pulp pressure increased from 7.5±1.1 mm Hg and 7.2±1 mm Hg to 25.4±3.1 mm Hg and 22±4 mm Hg respectively.In e NOS-/-mice splenic pulp pressure was increased after 1 d(P=NS),after which it decreased and by 7 d was not significantly elevated when compared to 7 d sham operated controls(6.9±0.6 mm Hg and 7.3±0.8 mm Hg respectively,P=0.3).Abdominal aortic flow was increased by 80%and 73%in 7 d portal vein ligated wild type and i NOS when compared to shams,whereas there was no significant difference in 7 d portal vein ligated e NOS-/-mice when compared to shams.Endothelin-1 induced a rapid reduction in abdominal aortic blood flow in wild type,e NOS-/-and i NOS-/-sham mice(50%±8%,73%±9%and 47%±9%respectively).Following portal vein ligation endothelin-1 reduction in blood flow was significantly diminished in each mouse group.Abdominal aortic flow was reduced by 19%±9%,32%±10%and 9%±9%in wild type,e NOS-/-and i NOS-/-mice respectively.CONCLUSION:Aberrant endothelin-1 response in murine portal hypertension is NOS isoform independent.Moreover,portal hypertension in the portal vein ligation model is independent of ET-1 function.

Taurine protects against retinal and optic nerve damage induced by endothelin-1 in rats via antioxidant effects

Endothelin-1（ET-1）, a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine（TAU）, a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co-or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress.

Antifibrotic effects of ambrisentan,an endothelin-A receptor antagonist,in a non-alcoholic steatohepatitis mouse model

AIM: To examine the effects of the endothelin type A receptor antagonist ambrisentan on hepatic steatosis and fibrosis in a steatohepatitis mouse model.METHODS: Fatty liver shionogi(FLS) FLS-ob/ob mice(male, 12 wk old) received ambrisentan(2.5 mg/kg orally per day; n = 8) or water as a control(n = 5) for 4 wk. Factors were compared between the two groups, including steatosis, fibrosis, inflammation, and endothelin-related gene expression in the liver.RESULTS: In the ambrisentan group, hepatic hydroxyproline content was significantly lower than in the control group(18.0 μg/g ± 6.1 μg/g vs 33.9 μg/g ± 13.5 μg/g liver, respectively, P = 0.014). Hepatic fibrosis estimated by Sirius red staining and areas positive for α-smooth muscle actin, indicative of activated hepatic stellate cells, were also significantly lower in the ambrisentan group(0.46% ± 0.18% vs 1.11% ± 0.28%, respectively, P = 0.0003; and 0.12% ± 0.08% vs 0.25% ± 0.11%, respectively, P = 0.047). Moreover, hepatic RNA expression levels of procollagen-1 and tissue inhibitor of metalloproteinase-1(TIMP-1) were significantly lower by 60% and 45%, respectively, in the ambrisentan group. Inflammation, steatosis, and endothelin-related m RNA expression in the liver were not significantly different between the groups.CONCLUSION: Ambrisentan attenuated the progression of hepatic fibrosis by inhibiting hepatic stellate cell activation and reducing procollagen-1 and TIMP-1 gene expression. Ambrisentan did not affect inflammation or steatosis.

The Releasing Effects of Captopril and Sodiun Nitroprusside on Endothelin-1 in Vascular Smooth Muscle Cell

Objective To investigate the influence of captoprial and SNP on the release of ET -1 in cultured VSMC of rats. Methods Measurement of endothelin - 1 levels by radioimmljnoassay in various concentrations of captopril and/or sodium nitroprusside in cultured vascular smooth muscle cell (VSMC) of rats. Results Both captopril and SNP could reduce the high ET - 1 levels of VSMC which were caused by Ang Ⅱ. There was a linear relationship between Ang Ⅱlevels and ET -1 production ( r = 0. 760, P <0. 001 ) . Conclusion Endothelin - 1 may accelerate the formation and development of atherosclerosis through inhibiting endogenous NO production by VSMC. ACEI or NO inhibition of ET -1 release could reduce atherosclerosis formation.

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic rate.However,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia patients.Similarly in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive decline.Nitric oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous system.Recently,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular dementia.This review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular dementia.Additionally,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

Nitric oxide removal from flue gas coupled with the Fe^(Ⅱ)EDTA regeneration by ultraviolet irradiation

During wet complexation denitrification of flue gas,Fe^(Ⅱ)EDTA regeneration,also known as reducing Fe^(Ⅱ)EDTA and Fe^(Ⅱ)EDTA-nitric oxide(NO)to Fe^(Ⅱ)EDTA,is crucial.In this paper,ultraviolet(UV)light was used for the first time to reduce Fe^(Ⅱ)EDTA-NO.The experimental result demonstrated that Fe^(Ⅱ)EDTA-NO reduction rate increased with UV power increasing,elevated temperature,and initial Fe^(Ⅱ)EDTA-NO concentration decreasing.Fe^(Ⅱ)EDTA-NO reduction rate increased first and then decreased as pH value increased(2.0-10.0).Fe^(Ⅱ)EDTA-NO reduction with UV irradiation presented a first order reaction with respect to Fe^(Ⅱ)EDTA-NO.Compared with other Fe^(Ⅱ)EDTA regeneration methods,Fe^(Ⅱ)EDTA regeneration with UV show more superiority through comprehensive consideration of regeneration rate and procedure.Subsequently,NO absorption experiment by Fe^(Ⅱ)EDTA solution with UV irradiation confirmed that UV can significantly promote the NO removal performance of Fe^(Ⅱ)EDTA.Appropriate oxygen concentration(3%(vol))and acidic environment(pH=4)was favorable for NO removal.With UV power increasing as well as temperature decreasing,NO removal efficiency rose.In addition,the mechanism research indicates that NO from flue gas is mostly converted to NO_(2)-,NO_(3)-,NH_(4)^(+),N_(2),and N_(2)O with Fe^(Ⅱ)EDTA absorption liquid with UV irradiation.UV strengthens NO removal in Fe^(Ⅱ)EDTA absorption liquid by forming a synergistic effect of oxidation-reduction-complexation.Finally,compared with NO removal methods with Fe^(Ⅱ)EDTA,Fe^(Ⅱ)EDTA combined UV system shows prominent technology advantage in terms of economy and secondary pollution.

Elimination of methicillin‑resistant Staphylococcus aureus biofilms on titanium implants via photothermally‑triggered nitric oxide and immunotherapy for enhanced osseointegration

Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to explore more effective approaches for the treatment of MRSA biofilm infections.Methods:Herein,an interfacial functionalization strategy is proposed by the integration of mesoporous polydopamine nanoparticles(PDA),nitric oxide(NO)release donor sodium nitroprusside(SNP)and osteogenic growth peptide(OGP)onto Ti implants,denoted as Ti-PDA@SNP-OGP.The physical and chemical properties of Ti-PDA@SNP-OGP were assessed by scanning electron microscopy,X-ray photoelectron spectroscope,water contact angle,photothermal property and NO release behavior.The synergistic antibacterial effect and elimination of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein diacetate probe,1-N-phenylnaphthylamine assay,adenosine triphosphate intensity,O-nitrophenyl-β-D-galactopyranoside hydrolysis activity,bicinchoninic acid leakage.Fluorescence staining,assays for alkaline phosphatase activity,collagen secretion and extracellular matrix mineralization,quantitative real‑time reverse transcription‑polymerase chain reaction,and enzyme-linked immunosorbent assay(ELISA)were used to evaluate the inflammatory response and osteogenic ability in bone marrow stromal cells(MSCs),RAW264.7 cells and their co-culture system.Giemsa staining,ELISA,micro-CT,hematoxylin and eosin,Masson's trichrome and immunohistochemistry staining were used to evaluate the eradication of MRSA biofilms,inhibition of inflammatory response,and promotion of osseointegration of Ti-PDA@SNP-OGP in vivo.Results:Ti-PDA@SNP-OGP displayed a synergistic photothermal and NO-dependent antibacterial effect against MRSA following near-infrared light(NIR)irradiation,and effectively eliminated the formed MRSA biofilms by inducing reactive oxygen species(ROS)-mediated oxidative stress,destroying bacterial membrane integrity and causing leakage of intracellular components(P<0.01).In vitro experiments revealed that Ti-PDA@SNP-OGP not only facilitated osteogenic differentiation of MSCs,but also promoted the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2-phenotype(P<0.05 or P<0.01).The favorable osteo-immune microenvironment further facilitated osteogenesis of MSCs and the anti-inflammation of RAW264.7 cells via multiple paracrine signaling pathways(P<0.01).In vivo evaluation confirmed the aforementioned results and revealed that Ti-PDA@SNP-OGP induced ameliorative osseointegration in an MRSA-infected femoral defect implantation model(P<0.01).Conclusions:Ti-PDA@SNP-OGP is a promising multi-functional material for the high-efficient treatment of MRSA infections in implant replacement surgeries.

Carbon Monoxide Modulates Auxin Transport and Nitric Oxide Signaling in Plants under Iron Deficiency Stress

Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in modulating the plant’s response to iron deficiency.Iron deficiency leads to an increase in the activity of heme oxygenase(HO)and the subsequent generation of CO.Additionally,it alters the polar subcellular distribution of Pin-Formed 1(PIN1)proteins,resulting in enhanced auxin transport.This alteration,in turn,leads to an increase in NO accumulation.Furthermore,iron deficiency enhances the activity of ferric chelate reductase(FCR),as well as the expression of the Fer-like iron deficiency-induced transcription factor 1(FIT)and the ferric reduction oxidase 2(FRO2)genes in plant roots.Overexpression of the long hypocotyl 1(HY1)gene,which encodes heme oxygenase,or the CO donor treatment resulted in enhanced basipetal auxin transport,higher FCR activity,and the expression of FIT and FRO2 genes under Fe deficiency.Here,a potential mechanism is proposed:CO and NO interact with auxin to address iron deficiency stress.CO alters auxin transport,enhancing its accumulation in roots and up-regulating key iron-related genes like FRO2 and IRT1.Elevated auxin levels affect NO signaling,leading to greater sensitivity in root development.This interplay promotes FCR activity,which is crucial for iron absorption.Together,these molecules enhance iron uptake and root growth,revealing a novel aspect of plant physiology in adapting to environmental stress.

Operation room nursing based on humanized nursing mode combined with nitric oxide on rehabilitation effect after lung surgery

BACKGROUND With advancements in the diagnosis and treatment of lung diseases,lung segment surgery has become increasingly common.Postoperative rehabilitation is critical for patient recovery,yet challenges such as complications and adverse outcomes persist.Incorporating humanized nursing modes and novel treatments like nitric oxide inhalation may enhance recovery and reduce postoperative complications.AIM To evaluate the effects of a humanized nursing mode combined with nitric oxide inhalation on the rehabilitation outcomes of patients undergoing lung surgery,focusing on pulmonary function,recovery speed,and overall treatment costs.METHODS A total of 79 patients who underwent lung surgery at a tertiary hospital from March 2021 to December 2021 were divided into a control group(n=39)receiving a routine nursing program and an experimental group(n=40)receiving additional humanized nursing interventions and atomized inhalation of nitric oxide.Key indicators were compared between the two groups alongside an analysis of treatment costs.RESULTS The experimental group demonstrated significant improvements in pulmonary function,reduced average recovery time,and lower total treatment costs compared to the control group.Moreover,the quality of life in the experimental group was significantly better in the 3 months post-surgery,indicating a more effective rehabilitation process.CONCLUSION The combination of humanized nursing mode and nitric oxide inhalation in postoperative care for lung surgery patients significantly enhances pulmonary rehabilitation outcomes,accelerates recovery,and reduces economic burden.This approach offers a promising reference for improving patient care and rehabilitation efficiency following lung surgery.

Early changes of endothelin,nitric oxide and arginine-vasopressin in patients with acute cerebral injury

Objective: To investigate the early changes and clinical significance of plasma endothelin (ET), nitric oxide (NO) and arginine vasopressin (AVP) in patients with acute moderate or severe cerebral injury. Methods: The early (at 24 hours after injury) plasma concentrations of ET, NO and AVP were measured with radioimmunoassay and Green technique in 48 cases of acute moderate (GCS≤8 in 27cases ) or severe (GCS>8 in 21 cases) cerebral injury (Group A), in 42 cases of non cerebral injury (Group B) and in 38 normal individuals (Group C), respectively. Results: The early plasma concentrations of ET ( 109.73 ng/L±12.61 ng/L ), NO ( 92.82 μmol/L± 18.21 μmol/L ) and AVP ( 49.78 ng/L±14.29 ng/L ) in Group A were higher than those in Group B ( 67.90 ng/L ±11.33 ng/L , 52.66 μmol/L±12.82 μmol/L and 29.93 ng/L±12.11 ng/L , respectively, P<0.01 ) and Group C ( 50.65 ng/L±17.12 ng/L , 36.12 μmol/L ±12.16 μmol/L and 5.18 ng/L ± 4.18 ng/L , respectively, P<0.001 ). The amounts of ET, NO and AVP in patients with severe cerebral injury were 116.18 ng/L± 18.12 ng/L , 108.19 μmol/L±13.28 μmol/L and 58.13 ng/L±16.78 ng/L , respectively, which were significantly higher than that of the patients with moderate cerebral injury ( 92.33 ng/L±16.32 ng/L , 76.38 μmol/L ±12.71 μmol/L and 36.18 ng/L±12.13 ng/L respectively, P<0.01 ). The early levels of ET, NO and AVP in Group A were negatively related to the GCS scales. The amounts of ET, NO and AVP were 126.23 ng/L± 15.23 ng/L , 118.18 μmol/L±10.12 μmol/L and 63.49 ng/L±14.36 ng/L respectively in patients with subdural hematoma, which were significantly higher than those in patients with epidural hematoma ( 81.13 ng/L ±12.37 ng/L , 68.02 μmol/L±13.18 μmol/L and 45.63 ng/L±12.41 ng/L respectively, P<0.01 ). The plasma concentrations of ET, NO and AVP in stable duration (at 336 hours after injury) in Group A and Group B were similar to those in Group C. Conclusions: ET, NO and AVP were related to the pathophysiological process that occurs in the early stage of acute cerebral injury and the values of ET, NO and AVP correlate positively with the clinical manifestations. The changes of plasma ET, NO and AVP can be regarded as important indices to assess the severity of acute cerebral injury.

Clinical efficacy of Chifeng Yingyuan manipulation for migraine and its effects on endothelin and nitric oxide

Objective To observe clinical efficacy of Ch/J：eng Yingyuan manipulation for migraine and its effects on endothelin （ET） and nitric oxide （NO）. Methods One hundred and seventeen cases were randomly divided into a treatment group （59 cases） and a control group （58 cases）. The Chifeng Yingyuan manipulation was applied in the treatment group while oral administration of flunarizine hydrochloride capsules was applied in the control group for consecutive 4 weeks. Before and after the treatment, the clinical efficacy and migraine score in both groups were compared; radioimmunoassay was used to test level of ET while nitrate reductase method was for level of NO. Results Compared between two groups, the total effective rate was 91.5% in the treatment group, which was superior to 70.7% in the control group （P〈0.05）. After the treatment, the migraine scores were both significantly decreased in two groups （P〈0.05, P〈0.01）, which was more obvious in the treatment group （P〈0.05）. The level of ET and NO was significantly changed after treatment （P〈0.05, P〈0.01）. Compared between two groups, the improvement of ET and NO in the treatment group was better than that in the control group （both P〈0.05）. Conclusion The Chifeng Yingyuan manipulation has positive effect on migraine without any adverse reaction, which could maintain cerebrovascular vasomotor function by regulating level of ET and NO in the plasma.