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1.
Am J Physiol Renal Physiol ; 326(1): F95-F104, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37916287

RESUMO

In the current study, we took advantage of the loss of protection from hypertension in SSCD247-/- rats to characterize the pathological effects of renal T-cells in isolation from the confounding effects of elevated renal perfusion pressure. Male SSCD247-/- and SSCD247+/+ littermates were fed 4.0% NaCl (high salt) diet to induce hypertension. Blood pressure was assessed continuously throughout the time course with radiotelemetry. Urine albumin and protein excretion were assessed on the final day of high salt. Renal injury and medullary transcriptome were assessed after completion of the high salt protocol. In contrast to previous studies, mean arterial pressure was not significantly different between SSCD247-/- and SSCD247+/+ rats. Despite this lack of pressure difference, urinary albumin was significantly lower in SSCD247-/- rats than their wild-type littermates. In the outer medulla, substantially more transcriptomic changes were found to correlate with endpoint blood pressure than with the absence of presence of renal T-cells. We also demonstrated that renal histological damage was driven by elevated renal perfusion pressure rather than the presence of renal T-cells. In conclusion, using the loss of protection from hypertension in SSCD247-/- rats, we demonstrated that renal perfusion pressure has more profound pathological effects on the kidney than renal T-cells. However, renal T-cells, independently of blood pressure, modulate the progression of albuminuria.NEW & NOTEWORTHY In vivo studies in a T-cell-deficient rat model of salt-sensitive hypertension (SSCD247-/- rats) were used to evaluate the role of T-cells on the development of hypertension and renal damage. Detailed physiological and transcriptomic analysis demonstrated no difference in blood pressure between rats with (SSCD247+/+) or without (SSCD247-/-) T-cells. Despite this, albuminuria was significantly lower in SSCD247-/- rats than SSCD247+/+ rats.


Assuntos
Hipertensão , Transcriptoma , Ratos , Masculino , Animais , Albuminúria/metabolismo , Linfócitos T/metabolismo , Ratos Endogâmicos Dahl , Rim/metabolismo , Hipertensão/metabolismo , Pressão Sanguínea , Cloreto de Sódio na Dieta/metabolismo , Albuminas/metabolismo
2.
Am J Physiol Regul Integr Comp Physiol ; 325(4): R411-R422, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37519252

RESUMO

Renal denervation (RDN) is a potential therapy for drug-resistant hypertension. However, whether its effects are mediated by ablation of efferent or afferent renal nerves is not clear. Previous studies have implicated that renal inflammation and the sympathetic nervous system are driven by the activation of afferent and efferent renal nerves. RDN attenuated the renal inflammation and sympathetic activity in some animal models of hypertension. In the 2 kidney,1 clip (2K1C) model of renovascular hypertension, RDN also decreased sympathetic activity; however, mechanisms underlying renal and central inflammation are still unclear. We tested the hypothesis that the mechanisms by which total RDN (TRDN; efferent + afferent) and afferent-specific RDN (ARDN) reduce arterial pressure in 2K1C rats are the same. Male Sprague-Dawley rats were instrumented with telemeters to measure mean arterial pressure (MAP), and after 7 days, a clip was placed on the left renal artery. Rats underwent TRDN, ARDN, or sham surgery of the clipped kidney and MAP was measured for 6 wk. Weekly measurements of water intake (WI), urine output (UO), and urinary copeptin were conducted, and urine was analyzed for cytokines/chemokines. Neurogenic pressor activity (NPA) was assessed at the end of the protocol calculated by the depressor response after intraperitoneal injection of hexamethonium. Rats were euthanized and the hypothalamus and kidneys removed for measurement of cytokine content. MAP, NPA, WI, and urinary copeptin were significantly increased in 2K1C-sham rats, and these responses were abolished by both TRDN and ARDN. 2K1C-sham rats presented with renal and hypothalamic inflammation and these responses were largely mitigated by TRDN and ARDN. We conclude that RDN attenuates 2K1C hypertension primarily by ablation of afferent renal nerves which disrupts bidirectional renal neural-immune pathways.NEW & NOTEWORTHY Hypertension resulting from reduced perfusion of the kidney is dependent on renal sensory nerves, which are linked to inflammation in the kidney and hypothalamus. Afferent renal nerves are required for chronic increases in both water intake and vasopressin release observed following renal artery stenosis. Findings from this study suggest an important role of renal sensory nerves that has previously been underestimated in the pathogenesis of 2K1C hypertension.


Assuntos
Hipertensão Renovascular , Hipertensão , Nefrite , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Rim , Sistema Nervoso Simpático , Hipotálamo , Inflamação , Pressão Sanguínea/fisiologia
3.
Am J Physiol Renal Physiol ; 323(3): F349-F360, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900340

RESUMO

Aromatase is a monooxygenase that catalyzes the rate-limiting step of estrogen biosynthesis from androgens. Aromatase inhibitors are widely used for the treatment of patients with hormone receptor-positive breast cancer. However, the effects of aromatase inhibitors on cardiovascular and renal health in females are understudied. Given that estrogen is protective against cardiovascular and kidney diseases, we hypothesized that aromatase inhibition elevates blood pressure and induces kidney injury in female Sprague-Dawley rats. Twelve-week-old female rats were implanted with radiotelemetry transmitters to continuously monitor blood pressure. After baseline blood pressure recording, rats were randomly assigned to treatment with the aromatase inhibitor anastrozole (ASZ) or vehicle (Veh) in drinking water. Twenty days after treatment initiation, rats were shifted from a normal-salt (NS) diet to a high-salt (HS) diet for an additional 40 days. Rats were euthanized 60 days after treatment initiation. Body weight increased in both groups over the study period, but the increase was greater in the ASZ-treated group than in the Veh-treated group. Mean arterial pressure increased in ASZ-treated rats during the NS and HS diet phases but remained unchanged in Veh-treated rats. In addition, urinary excretion of albumin and kidney injury marker-1 and plasma urea were increased in response to aromatase inhibition. Furthermore, histological assessment revealed that ASZ treatment increased morphological evidence of renal tubular injury and proximal tubular brush border loss. In conclusion, chronic aromatase inhibition in vivo with ASZ increases blood pressure and markers of renal proximal tubular injury in female Sprague-Dawley rats, suggesting an important role for aromatization in the maintenance cardiovascular and renal health in females.NEW & NOTEWORTHY Aromatase enzyme catalyzes the rate-limiting step in estrogen biosynthesis. Aromatase inhibitors are clinically used for the treatment of patients with breast cancer; however, the impact of inhibiting aromatization on blood pressure and renal function is incompletely understood. The present findings demonstrate that systemic anastrozole treatment increases blood pressure and renal tubular injury markers in female rats fed a high-salt diet, suggesting an important role for aromatization in preserving cardiovascular and renal health in females.


Assuntos
Inibidores da Aromatase , Hipertensão , Anastrozol/efeitos adversos , Animais , Inibidores da Aromatase/efeitos adversos , Biomarcadores , Pressão Sanguínea , Estrogênios , Feminino , Hipertensão/induzido quimicamente , Rim/patologia , Neoplasias , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio na Dieta/efeitos adversos
4.
J Am Chem Soc ; 141(46): 18600-18611, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31656074

RESUMO

The mechanism of R2BH-catalyzed hydroboration of alkynes by 1,3,2-dioxaborolanes has been investigated by in situ 19F NMR spectroscopy, kinetic simulation, isotope entrainment, single-turnover labeling (10B/2H), and density functional theory (DFT) calculations. For the Cy2BH-catalyzed hydroboration 4-fluorophenylacetylene by pinacolborane, the resting state is the anti-Markovnikov addition product ArCH = CHBCy2. Irreversible and turnover-rate limiting reaction with pinacolborane (k ≈ 7 × 10-3 M-1 s-1) regenerates Cy2BH and releases E-Ar-CH═CHBpin. Two irreversible events proceed in concert with turnover. The first is a Markovnikov hydroboration leading to regioisomeric Ar-C(Bpin)═CH2. This is unreactive to pinacolborane at ambient temperature, resulting in catalyst inhibition every ∼102 turnovers. The second is hydroboration of the alkenylboronate to give ArCH2CH(BCy2)Bpin, again leading to catalyst inhibition. 9-BBN behaves analogously to Cy2BH, but with higher anti-Markovnikov selectivity, a lower barrier to secondary hydroboration, and overall lower efficiency. The key process for turnover is B-H/C-B metathesis, proceeding by stereospecific transfer of the E-alkenyl group within a transient, µ-B-H-B bridged, 2-electron-3-center bonded B-C-B intermediate.

5.
J Paediatr Child Health ; 55(4): 477-480, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30957329

RESUMO

To answer the clinical question 'Among late preterm infants are there any interventions that improve the rates of breastfeeding and the use of breast milk compared with current practice?'. MEDLINE via Ovid, Embase via Ovid, the Maternity and Infant Care Database and the Cochrane Library were searched for relevant articles. Articles were excluded if they did not discuss specific interventions to improve breastfeeding, for example, if they only commented on factors such as age, race and education. Articles were also excluded if they were not specific to the late preterm infant population. A total of 516 articles were found and screened by title and abstract independently by two reviewers. The full text of 17 articles was independently reviewed. The reference lists of these full-text articles were screened, and 14 abstracts were subsequently reviewed. The final analysis included three studies. There is limited high-quality research evidence for interventions to improve breastfeeding in late preterm infants. In the absence of robust academic research, clinical practice should be guided by clinical expertise and involve a multidisciplinary team, including qualified lactation consultants. While it seems reasonable for hospitals to support interventions that improve breastfeeding in term infants, managing late preterm infants as healthy term infants without additional specialist support may result in high breastfeeding failure rates among late preterm infants.


Assuntos
Aleitamento Materno/métodos , Idade Gestacional , Cuidado do Lactente/métodos , Recém-Nascido Prematuro , Leite Humano , Desenvolvimento Infantil , Feminino , Seguimentos , Humanos , Recém-Nascido , Gravidez , Fatores de Tempo
6.
Physiol Genomics ; 50(6): 440-447, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29602296

RESUMO

Studies exploring the development of hypertension have traditionally been unable to distinguish which of the observed changes are underlying causes from those that are a consequence of elevated blood pressure. In this study, a custom-designed servo-control system was utilized to precisely control renal perfusion pressure to the left kidney continuously during the development of hypertension in Dahl salt-sensitive rats. In this way, we maintained the left kidney at control blood pressure while the right kidney was exposed to hypertensive pressures. As each kidney was exposed to the same circulating factors, differences between them represent changes induced by pressure alone. RNA sequencing analysis identified 1,613 differently expressed genes affected by renal perfusion pressure. Three pathway analysis methods were applied, one a novel approach incorporating arterial pressure as an input variable allowing a more direct connection between the expression of genes and pressure. The statistical analysis proposed several novel pathways by which pressure affects renal physiology. We confirmed the effects of pressure on p-Jnk regulation, in which the hypertensive medullas show increased p-Jnk/Jnk ratios relative to the left (0.79 ± 0.11 vs. 0.53 ± 0.10, P < 0.01, n = 8). We also confirmed pathway predictions of mitochondrial function, in which the respiratory control ratio of hypertensive vs. control mitochondria are significantly reduced (7.9 ± 1.2 vs. 10.4 ± 1.8, P < 0.01, n = 6) and metabolomic profile, in which 14 metabolites differed significantly between hypertensive and control medullas ( P < 0.05, n = 5). These findings demonstrate that subtle differences in the transcriptome can be used to predict functional changes of the kidney as a consequence of pressure elevation.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Inflamação/genética , Medula Renal/fisiologia , Medula Renal/fisiopatologia , Redes e Vias Metabólicas/genética , Perfusão , Animais , Teorema de Bayes , Respiração Celular , Hipertensão/genética , Metaboloma , Metabolômica , Mitocôndrias/metabolismo , Ratos Endogâmicos Dahl , Análise de Regressão , Software
7.
J Clin Immunol ; 38(7): 768-777, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30219982

RESUMO

Individuals with common variable immunodeficiency (CVID) have an increased risk of gastric cancer, and gastrointestinal lymphoma, yet screening for premalignant gastric lesions is rarely offered routinely to these patients. Proposed screening protocols are not widely accepted and are based on gastric cancer risk factors that are not applicable to all CVID patients. Fifty-two CVID patients were recruited for screening gastroscopy irrespective of symptoms or blood results and were compared to 40 controls presenting for gastroscopy for other clinical indications. Overall, 34% of CVID patients had intestinal metaplasia (IM), atrophic gastritis or moderate to severe non-atrophic gastritis, which can increase the risk of gastric cancer, compared to 7.5% of controls (p < 0.01). Focal nodular lymphoid hyperplasia, a precursor lesion for gastrointestinal lymphoma, was seen in eight CVID patients (16%), one of whom was diagnosed with gastrointestinal lymphoma on the same endoscopy. High-risk gastric pathology was associated with increased time since diagnosis of CVID, smoking, Helicobacter pylori, a low-serum pepsinogen I concentration, and diarrhea, but not pepsinogen I/II ratio, iron studies, vitamin B12 levels or upper gastrointestinal symptoms. There was a lower rate of detection of IM when fewer biopsies were taken, and IM and gastric atrophy were rarely predicted by the endoscopist macroscopically, highlighting the need for standardized biopsy protocols. The prevalence of premalignant gastric lesions in patients with CVID highlights the need for routine gastric screening. We propose a novel gastric screening protocol to detect early premalignant lesions and reduce the risk of gastric cancer and gastric lymphoma in these patients.


Assuntos
Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Biópsia , Imunodeficiência de Variável Comum/etiologia , Detecção Precoce de Câncer , Feminino , Gastrite Atrófica/complicações , Gastroscopia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Programas de Rastreamento , Metaplasia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões Pré-Cancerosas , Prevalência , Vigilância em Saúde Pública , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Inquéritos e Questionários , Adulto Jovem
8.
Circulation ; 133(14): 1360-70, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26951843

RESUMO

BACKGROUND: The hypertensive syndrome of Apparent Mineralocorticoid Excess is caused by loss-of-function mutations in the gene encoding 11ß-hydroxysteroid dehydrogenase type 2 (11ßHSD2), allowing inappropriate activation of the mineralocorticoid receptor by endogenous glucocorticoid. Hypertension is attributed to sodium retention in the distal nephron, but 11ßHSD2 is also expressed in the brain. However, the central contribution to Apparent Mineralocorticoid Excess and other hypertensive states is often overlooked and is unresolved. We therefore used a Cre-Lox strategy to generate 11ßHSD2 brain-specific knockout (Hsd11b2.BKO) mice, measuring blood pressure and salt appetite in adults. METHODS AND RESULTS: Basal blood pressure, electrolytes, and circulating corticosteroids were unaffected in Hsd11b2.BKO mice. When offered saline to drink, Hsd11b2.BKO mice consumed 3 times more sodium than controls and became hypertensive. Salt appetite was inhibited by spironolactone. Control mice fed the same daily sodium intake remained normotensive, showing the intrinsic salt resistance of the background strain. Dexamethasone suppressed endogenous glucocorticoid and abolished the salt-induced blood pressure differential between genotypes. Salt sensitivity in Hsd11b2.BKO mice was not caused by impaired renal sodium excretion or volume expansion; pressor responses to phenylephrine were enhanced and baroreflexes impaired in these animals. CONCLUSIONS: Reduced 11ßHSD2 activity in the brain does not intrinsically cause hypertension, but it promotes a hunger for salt and a transition from salt resistance to salt sensitivity. Our data suggest that 11ßHSD2-positive neurons integrate salt appetite and the blood pressure response to dietary sodium through a mineralocorticoid receptor-dependent pathway. Therefore, central mineralocorticoid receptor antagonism could increase compliance to low-sodium regimens and help blood pressure management in cardiovascular disease.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Fissura/fisiologia , Hipertensão/genética , Síndrome de Excesso Aparente de Minerolocorticoides/fisiopatologia , Proteínas do Tecido Nervoso/deficiência , Receptores de Mineralocorticoides/fisiologia , Cloreto de Sódio na Dieta/toxicidade , Núcleo Solitário/enzimologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/fisiologia , Animais , Barorreflexo/efeitos dos fármacos , Corticosterona/sangue , Dexametasona/farmacologia , Comportamento de Ingestão de Líquido , Genes Sintéticos , Hipertensão/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Síndrome de Excesso Aparente de Minerolocorticoides/tratamento farmacológico , Síndrome de Excesso Aparente de Minerolocorticoides/genética , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Néfrons/fisiopatologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Nestina/genética , Neurônios/fisiologia , Potássio/urina , RNA Mensageiro/biossíntese , Reflexo Anormal , Núcleo Solitário/fisiopatologia , Espironolactona/farmacologia
10.
J Phys Chem A ; 121(1): 4-15, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27755879

RESUMO

The Criegee intermediate acetone oxide, (CH3)2COO, is formed by laser photolysis of 2,2-diiodopropane in the presence of O2 and characterized by synchrotron photoionization mass spectrometry and by cavity ring-down ultraviolet absorption spectroscopy. The rate coefficient of the reaction of the Criegee intermediate with SO2 was measured using photoionization mass spectrometry and pseudo-first-order methods to be (7.3 ± 0.5) × 10-11 cm3 s-1 at 298 K and 4 Torr and (1.5 ± 0.5) × 10-10 cm3 s-1 at 298 K and 10 Torr (He buffer). These values are similar to directly measured rate coefficients of anti-CH3CHOO with SO2, and in good agreement with recent UV absorption measurements. The measurement of this reaction at 293 K and slightly higher pressures (between 10 and 100 Torr) in N2 from cavity ring-down decay of the ultraviolet absorption of (CH3)2COO yielded even larger rate coefficients, in the range (1.84 ± 0.12) × 10-10 to (2.29 ± 0.08) × 10-10 cm3 s-1. Photoionization mass spectrometry measurements with deuterated acetone oxide at 4 Torr show an inverse deuterium kinetic isotope effect, kH/kD = (0.53 ± 0.06), for reactions with SO2, which may be consistent with recent suggestions that the formation of an association complex affects the rate coefficient. The reaction of (CD3)2COO with NO2 has a rate coefficient at 298 K and 4 Torr of (2.1 ± 0.5) × 10-12 cm3 s-1 (measured with photoionization mass spectrometry), again similar to rate for the reaction of anti-CH3CHOO with NO2. Cavity ring-down measurements of the acetone oxide removal without added reagents display a combination of first- and second-order decay kinetics, which can be deconvolved to derive values for both the self-reaction of (CH3)2COO and its unimolecular thermal decay. The inferred unimolecular decay rate coefficient at 293 K, (305 ± 70) s-1, is similar to determinations from ozonolysis. The present measurements confirm the large rate coefficient for reaction of (CH3)2COO with SO2 and the small rate coefficient for its reaction with water. Product measurements of the reactions of (CH3)2COO with NO2 and with SO2 suggest that these reactions may facilitate isomerization to 2-hydroperoxypropene, possibly by subsequent reactions of association products.

11.
Physiol Genomics ; 46(11): 398-410, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24714719

RESUMO

The goal of the present study was to narrow a region of chromosome 13 to only several genes and then apply unbiased statistical approaches to identify molecular networks and biological pathways relevant to blood-pressure salt sensitivity in Dahl salt-sensitive (SS) rats. The analysis of 13 overlapping subcongenic strains identified a 1.37 Mbp region on chromosome 13 that influenced the mean arterial blood pressure by at least 25 mmHg in SS rats fed a high-salt diet. DNA sequencing and analysis filled genomic gaps and provided identification of five genes in this region, Rfwd2, Fam5b, Astn1, Pappa2, and Tnr. A cross-platform normalization of transcriptome data sets obtained from our previously published Affymetrix GeneChip dataset and newly acquired RNA-seq data from renal outer medullary tissue provided 90 observations for each gene. Two Bayesian methods were used to analyze the data: 1) a linear model analysis to assess 243 biological pathways for their likelihood to discriminate blood pressure levels across experimental groups and 2) a Bayesian graphical modeling of pathways to discover genes with potential relationships to the candidate genes in this region. As none of these five genes are known to be involved in hypertension, this unbiased approach has provided useful clues to be experimentally explored. Of these five genes, Rfwd2, the gene most strongly expressed in the renal outer medulla, was notably associated with pathways that can affect blood pressure via renal transcellular Na(+) and K(+) electrochemical gradients and tubular Na(+) transport, mitochondrial TCA cycle and cell energetics, and circadian rhythms.


Assuntos
Genoma/genética , Hipertensão/genética , Hipertensão/metabolismo , Transdução de Sinais/genética , Animais , Pressão Arterial/genética , Teorema de Bayes , Ritmo Circadiano/genética , Ciclo do Ácido Cítrico/genética , Perfilação da Expressão Gênica/métodos , Masculino , Mitocôndrias/genética , Potássio/metabolismo , Ratos , Ratos Endogâmicos Dahl , Análise de Sequência de DNA/métodos , Sódio/metabolismo , Cloreto de Sódio na Dieta/metabolismo
12.
Purinergic Signal ; 10(1): 71-101, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24265071

RESUMO

The involvement of purinergic signalling in kidney physiology and pathophysiology is rapidly gaining recognition and this is a comprehensive review of early and recent publications in the field. Purinergic signalling involvement is described in several important intrarenal regulatory mechanisms, including tuboglomerular feedback, the autoregulatory response of the glomerular and extraglomerular microcirculation and the control of renin release. Furthermore, purinergic signalling influences water and electrolyte transport in all segments of the renal tubule. Reports about purine- and pyrimidine-mediated actions in diseases of the kidney, including polycystic kidney disease, nephritis, diabetes, hypertension and nephrotoxicant injury are covered and possible purinergic therapeutic strategies discussed.


Assuntos
Nível de Saúde , Nefropatias/metabolismo , Rim/fisiologia , Receptores Purinérgicos/fisiologia , Transdução de Sinais/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico/fisiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/metabolismo , Nefropatias/diagnóstico
13.
J Phys Chem A ; 118(15): 2756-64, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24684215

RESUMO

Absorption cross-sections and quantum yields for NO2 production (ΦNO2) are reported for gaseous methyl, ethyl, n-propyl, and isopropyl nitrate at 294 K. Absorption cross-sections in the wavelength range of 240-320 nm agree well with prior determinations. NO2 quantum yields at photoexcitation wavelengths of 290, 295, and 315 nm are unity within experimental uncertainties for all of the alkyl nitrates studied and are independent of bath gas (N2) pressure for total sample pressures in the range of 250-700 Torr. When averaged over all wavelengths and sample pressures, values of ΦNO2 are 1.03 ± 0.05 (methyl nitrate), 0.98 ± 0.09 (ethyl nitrate), 1.01 ± 0.04 (n-propyl nitrate), and 1.00 ± 0.05 (isopropyl nitrate), with uncertainties corresponding to 1 standard deviation. Absorption cross-sections for ethyl nitrate, isopropyl nitrate, and two unsaturated dinitrate compounds, but-3-ene-1,2-diyl dinitrate and (Z)-but-2-ene-1,4-diyl dinitrate in acetonitrile solution, are compared to gas-phase values, and over the wavelength range of 260-315 nm, the gas-phase values are well-reproduced by dividing the liquid-phase cross-sections by 2.0, 1.6, 1.7, and 2.2, respectively. Reasonable estimates of the gas-phase absorption cross-sections for low-volatility organic nitrates can therefore be obtained by halving the values for acetonitrile solutions. The quantum yield for NO2 formation from photoexcitation of but-3-ene-1,2-diyl dinitrate at 290 nm is significantly lower than those for the alkyl (mono) nitrates: a best estimate of ΦNO2 ≤ 0.25 is obtained from the experimental measurements.

14.
Hypertension ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841853

RESUMO

BACKGROUND: Clinical trials of renal denervation for the treatment of hypertension have shown a variety of off-target improvements in conditions associated with sympathetic overactivity. This may be due to the ablation of sympathoexcitatory afferent renal nerves, which are overactive under conditions of renal inflammation. Renal IL (interleukin)-1ß is elevated in the deoxycorticosterone acetate-salt model of hypertension, and its activity may be responsible for the elevation in afferent renal nerve activity and arterial pressure. METHODS: Continuous blood pressure recording of deoxycorticosterone acetate-salt mice with IL-1R (IL-1 receptor) knockout or antagonism was used individually and combined with afferent renal denervation (ARDN) to assess mechanistic overlap. Protein quantification and histological analysis of kidneys were performed to characterize renal inflammation. RESULTS: ARDN attenuated deoxycorticosterone acetate-salt hypertension (-20±2-Δmm Hg mean arterial pressure [MAP] relative to control at study end) to a similar degree as total renal denervation (-21±2-Δmm Hg MAP), IL-1R knockout (-16±4-Δmm Hg MAP), or IL-1R antagonism (-20±3-Δmm Hg MAP). The combination of ARDN with knockout (-18±2-Δmm Hg MAP) or antagonism (-19±4-Δmm Hg MAP) did not attenuate hypertension any further than ARDN alone. IL-1R antagonism was found to have an acute depressor effect (-15±3-Δmm Hg MAP, day 10) in animals with intact renal nerves but not those with ARDN. CONCLUSIONS: These findings suggest that IL-1R signaling is partially responsible for the elevated afferent renal nerve activity, which stimulates central sympathetic outflow to drive deoxycorticosterone acetate-salt hypertension.

15.
Target Oncol ; 19(3): 333-342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38546944

RESUMO

BACKGROUND: Recurrent or refractory solid and central nervous system (CNS) tumours in paediatric patients have limited treatment options and carry a poor prognosis. The EnGeneIC Dream Vector (EDV) is a novel nanocell designed to deliver cytotoxic medication directly to the tumour. The epidermal growth factor receptor is expressed in several CNS and solid tumours and is the target for bispecific antibodies attached to the EDV. OBJECTIVE: To assess the safety and tolerability of EGFR-Erbitux receptor EnGeneIC Dream Vector with mitoxantrone (EEDVsMit) in children with recurrent / refractory solid or CNS tumours expressing EGFR. PATIENTS AND METHODS: Patients aged 2-21 years with relapsed or refractory CNS and solid tumours, or radiologically diagnosed diffuse intrinsic pontine glioma (DIPG), were treated in this phase I open-label study of single agent EEDVsMit. Thirty-seven patients' tumours were screened for EGFR expression. EEDVsMit was administered twice weekly in the first cycle and weekly thereafter. Standard dose escalation with a rolling 6 design was employed. Dosing commenced at 5 × 108 EEDVsMit per dose and escalated to 5 × 109 EEDVsMit per dose. RESULTS: EGFR expression was detected in 12 (32%) of the paediatric tumours tested. Nine patients were enrolled and treated on the trial, including three patients with diffuse midline glioma. Overall, EEDVsMit was well tolerated, with no dose-limiting toxicities observed. The most common drug-related adverse events were grade 1-2 fever, nausea and vomiting, rash, lymphopaenia, and mildly deranged liver function tests. All patients had disease progression, including one patient who achieved a mixed response as the best response. CONCLUSIONS: EGFR-Erbitux receptor targeted EnGeneIC Dream Vector with mitoxantrone can be safely delivered in paediatric patients aged 2-21 years with solid or CNS tumours harbouring EGFR expression. The discovery of EGFR expression in a high proportion of paediatric gliomas means that EGFR may be useful as a target for other treatment strategies. Targeted therapeutic-loaded EDVs may be worth exploring further for their role in stimulating an anti-tumour immune response. GOV IDENTIFIER: NCT02687386.


Assuntos
Neoplasias do Sistema Nervoso Central , Receptores ErbB , Humanos , Criança , Receptores ErbB/metabolismo , Adolescente , Masculino , Feminino , Pré-Escolar , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Adulto Jovem
16.
J Paediatr Child Health ; 54(11): 1273-1274, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30387269
17.
J Paediatr Child Health ; 54(11): 1269-1270, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30387268
18.
Vaccine ; 41(41): 5987-5993, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37633752

RESUMO

BACKGROUND: The rate of anaphylaxis following COVID-19 vaccinations is estimated to be 2-11 cases per million doses administered. However, adrenaline is occasionally used in individuals who are later diagnosed with immunisation stress-related responses, as their initial presenting signs and symptoms can appear similar to that of anaphylaxis. This study aims to describe the clinical profile of individuals who had received adrenaline following a COVID-19 vaccine and their subsequent revaccination outcomes. METHODS: We examined notifications of cases who had received adrenaline following a COVID-19 vaccine in New South Wales, Australia. The cases were classified into Brighton Collaboration Case Definition (BCCD) for anaphylaxis, their clinical presentation, management and subsequent revaccination outcomes were compared. RESULTS: From 22 February 2021 to 30 September 2021, there were 222 cases where adrenaline was administered. Of these, 32 (14 %) fulfilled Level 1 BCCD, 59 (27%) Level 2, 2 (1%) Level 3, 97 (44%) Level 4 and 32 (14 %) Level 5. The most commonly reported symptoms were sensation of throat closure (n = 116, 52%), difficulty breathing (n = 82, 37%) and nausea (n = 55, 25 %). Of the 176 (79%) individuals who proceeded to further vaccination, 89 (51%) received the same vaccine formulation and only 14 (8%) experienced another allergic adverse event with 9 (5%) receiving adrenaline. CONCLUSION: Less than one in five individuals who received adrenaline met Level 1 BCCD criteria for anaphylaxis. Many reactions that were treated with adrenaline had little to no diagnostic certainty of anaphylaxis and in such cases repeat vaccination had a high likelihood of being tolerated. Increased awareness and education on objective signs and symptoms of anaphylaxis is required to ensure appropriate use of adrenaline.


Assuntos
Anafilaxia , Vacinas contra COVID-19 , COVID-19 , Humanos , Anafilaxia/induzido quimicamente , Anafilaxia/epidemiologia , Austrália/epidemiologia , Vacinas contra COVID-19/efeitos adversos , Epinefrina/uso terapêutico , Imunização Secundária , Estudos Retrospectivos , Vacinação/efeitos adversos
19.
Am J Physiol Renal Physiol ; 303(4): F494-502, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22622456

RESUMO

In aldosterone target tissues, 11ß-hydroxysteroid dehydrogenase type 2 (11ßHSD2) is coexpressed with mineralocorticoid receptors (MR) and protects the receptor from activation by glucocorticoids. Null mutations in the encoding gene, HSD11B2, cause apparent mineralocorticoid excess, in which hypertension is thought to reflect volume expansion secondary to sodium retention. Hsd11b2(-/-) mice are indeed hypertensive, but impaired natriuretic capacity is associated with significant volume contraction, suggestive of a urine concentrating defect. Water turnover and the urine concentrating response to a 24-h water deprivation challenge were therefore assessed in Hsd11b2(-/-) mice and controls. Hsd11b2(-/-) mice have a severe and progressive polyuric/polydipsic phenotype. In younger mice (∼2 mo of age), polyuria was associated with decreased abundance of aqp2 and aqp3 mRNA. The expression of other genes involved in water transport (aqp4, slc14a2, and slc12a2) was not changed. The kidney was structurally normal, and the concentrating response to water deprivation was intact. In older Hsd11b2(-/-) mice (>6 mo), polyuria was associated with a severe atrophy of the renal medulla and downregulation of aqp2, aqp3, aqp4, slc14a2, and slc12a2. The concentrating response to water deprivation was impaired, and the natriuretic effect of the loop diuretic bumetanide was lost. In older Hsd11b2(-/-) mice, the V2 receptor agonist desmopressin did not restore full urine concentrating capacity. We find that Hsd11b2(-/-) mice develop nephrogenic diabetes insipidus. Gross changes to renal structure are observed, but these were probably secondary to sustained polyuria, rather than of developmental origin.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Diabetes Insípido/enzimologia , Capacidade de Concentração Renal/fisiologia , Rim/fisiologia , Envelhecimento , Animais , Diabetes Insípido/genética , Regulação da Expressão Gênica , Homeostase , Rim/anatomia & histologia , Capacidade de Concentração Renal/genética , Camundongos , Camundongos Knockout , Concentração Osmolar , Simportadores de Cloreto de Sódio-Potássio/genética , Simportadores de Cloreto de Sódio-Potássio/metabolismo , Água/metabolismo , Redução de Peso
20.
Clin Immunol ; 144(2): 159-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22772031

RESUMO

Analysis and mathematical modeling of T-lymphocyte perturbation following administration of granulocyte colony stimulating factor (G-CSF) and two large-scale aphereses are reported. 74 HIV-1 positive antiretroviral-treated individuals were infused with gene- or sham-transduced CD34+ hematopoietic stem cells (HSC) in a Phase II clinical trial. T cell numbers were examined in four phases: 1) during steady state; 2) increases in peripheral blood (PB) following G-CSF administration; 3) depletion post-aphereses and 4) reconstitution post HSC infusion. The present analysis provides the first direct estimate of CD4+ T cell distribution and trafficking in HIV-infected individuals on stable HAART, indicating that CD4+ T lymphocytes in PB represent 5.5% of the pool of CD4+ T lymphocytes that traffic to PB.


Assuntos
Infecções por HIV/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Remoção de Componentes Sanguíneos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Morte Celular/imunologia , Infecções por HIV/terapia , Transplante de Células-Tronco Hematopoéticas , Humanos , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Modelos Teóricos , Fenótipo , Fatores de Tempo
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