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1.
J Infect Dis ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429000

RESUMEN

INTRODUCTION: People living with the human immunodeficiency virus (PWH) have microvascular disease. Since perivascular adipose tissue (PVAT) regulates microvascular function and adipose tissue is inflamed in PWH, we tested the hypothesis that PWH have inflamed PVAT that impairs the function of their small vessels. METHODS: Subcutaneous small arteries were dissected with or without (+ or -) PVAT from a gluteal skin biopsy from 11 women with treated HIV (WWH) aged < 50 years and 10 matched women without HIV and studied on isometric myographs. Nitric oxide (NO) and reactive oxygen species (ROS) were measured by fluorescence microscopy. Adipokines and markers of inflammation and ROS were assayed in PVAT. RESULTS: PVAT surrounding the small arteries in control women significantly (P < 0.05) enhanced acetylcholine (Ach)-induced endothelium dependent relaxation and NO and reduced contractions to thromboxane and endothelin-1. However, these effects of PVAT were reduced significantly (P < 0.05) in WWH whose PVAT released less adiponectin but more markers of ROS and inflammation. Moderation of contractions by PVAT were correlated positively with adipose adiponectin. CONCLUSION: PVAT from WWH has oxidative stress, inflammation and reduced release of adiponectin that may contribute to enhanced contractions and therefore could promote small artery dysfunction.

2.
J Infect Dis ; 230(1): 67-77, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052698

RESUMEN

BACKGROUND: People with the human immunodeficiency virus (PWH) have microvascular disease. Because perivascular adipose tissue (PVAT) regulates microvascular function and adipose tissue is inflamed in PWH, we tested the hypothesis that PWH have inflamed PVAT that impairs the function of their small vessels. METHODS: Subcutaneous small arteries were dissected with or without PVAT from a gluteal skin biopsy from 11 women with treated HIV (WWH) aged < 50 years and 10 matched women without HIV, and studied on isometric myographs. Nitric oxide (NO) and reactive oxygen species (ROS) were measured by fluorescence microscopy. Adipokines and markers of inflammation and ROS were assayed in PVAT. RESULTS: PVAT surrounding the small arteries in control women significantly (P < .05) enhanced acetylcholine-induced endothelium-dependent relaxation and NO, and reduced contractions to thromboxane and endothelin-1. However, these effects of PVAT were reduced significantly (P < .05) in WWH whose PVAT released less adiponectin but more markers of ROS and inflammation. Moderation of contractions by PVAT were correlated positively with adipose adiponectin. CONCLUSIONS: PVAT from WWH has oxidative stress, inflammation, and reduced release of adiponectin, which may contribute to enhanced contractions and therefore could promote small-artery dysfunction.


Asunto(s)
Tejido Adiposo , Infecciones por VIH , Inflamación , Especies Reactivas de Oxígeno , Humanos , Femenino , Infecciones por VIH/fisiopatología , Infecciones por VIH/complicaciones , Tejido Adiposo/metabolismo , Adulto , Persona de Mediana Edad , Inflamación/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo , Adiponectina/metabolismo , Óxido Nítrico/metabolismo , Arterias/fisiopatología , Arterias/patología
3.
Biochemistry ; 2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-35436085

RESUMEN

CRISPR gene editing and control systems continue to emerge and inspire novel research and clinical applications. Advances in CRISPR performance such as optimizing the duration of activity in cells, tissues, and organisms, as well as limiting off-target activities, have been extremely important for expanding the utility of CRISPR-based systems. By investigating the effects of various chemical modifications in guide RNAs (gRNAs) at defined positions and combinations, we find that 2'-O-methyl-3'-phosphonoacetate (MP) modifications can be substantially more effective than 2'-O-methyl-3'-phosphorothioate (MS) modifications at the 3' ends of single-guide RNAs (sgRNAs) to promote high editing yields, in some instances showing an order of magnitude higher editing yield in human cells. MP-modified 3' ends are especially effective at promoting the activity of guide RNAs cotransfected with Cas messenger RNA (mRNA), as the gRNA must persist in cells until the Cas protein is expressed. We demonstrate such an MP enhancement for sgRNAs cotransfected with a BE4 mRNA for cytidine base editing and also demonstrate that MP at the 3' ends of prime editing guide RNAs (pegRNAs) cotransfected with PE2 mRNA can promote maximal prime editing yields. In the presence of serum, sgRNAs with MP-modified 3' ends showed marked improvements in editing efficiency over sgRNAs with MS-modified 3' ends codelivered with Cas9 mRNA and showed more modest improvements at enhancing the activity of transfected ribonucleoprotein (RNP) complexes. Our results suggest that MP should be considered as a performance-enhancing modification for the 3' ends of synthetic gRNAs, especially in situations where the guide RNAs may be susceptible to exonuclease-mediated degradation.

4.
Neurosurg Focus ; 53(4): E10, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36183183

RESUMEN

OBJECTIVE: Responsive neurostimulation (RNS) is a promising treatment for pediatric patients with drug-resistant epilepsy for whom resective surgery is not an option. The relative indications and risk for pediatric patients undergoing RNS therapy require further investigation. Here, the authors report their experience with RNS implantation and therapy in pediatric patients. METHODS: The authors performed a retrospective chart review to identify patients implanted with RNS depth or strip electrodes for the treatment of drug-resistant epilepsy at their institution between 2020 and 2022. Patient demographics, surgical variables, and patient seizure outcomes (Engel class and International League Against Epilepsy [ILAE] reporting) were evaluated. RESULTS: The authors identified 20 pediatric patients ranging in age from 8 to 21 years (mean 15 [SD 4] years), who underwent RNS implantation, including depth electrodes (n = 15), strip electrodes (n = 2), or both (n = 3). Patient seizure semiology, onset, and implantation strategy were heterogeneous, including bilateral centromedian nucleus (n = 5), mesial temporal lobe (n = 4), motor cortex or supplementary motor area (n = 7), or within an extratemporal epileptogenic zone (n = 4). There were no acute complications of RNS implantation (hemorrhage or stroke) or device malfunctions. One patient required rehospitalization for postoperative infection. At the longest follow-up (mean 10 [SD 7] months), 13% patients had Engel class IIB, 38% had Engel class IIIA, 6% had Engel class IIIB, 19% had Engel class IVA, 19% had Engel class IVB, and 6% had Engel class IVC outcomes. Using ILAE metrics, 6% were ILAE class 3, 25% were ILAE class 4, and 69% were ILAE class 5. CONCLUSIONS: This case series supports current literature suggesting that RNS is a safe and potentially effective surgical intervention for pediatric patients with drug-resistant epilepsy. The authors report comparable rates of serious adverse events to current RNS literature in pediatric and adult populations. Seizure outcomes may continue to improve with follow-up as stimulation strategy is refined and the chronic neuromodulatory effect evolves, as previously described in patients with RNS. Further large-scale, multicenter case series of RNS in pediatric patients with drug-resistant epilepsy are required to determine long-term pediatric safety and effectiveness.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Adolescente , Adulto , Niño , Epilepsia Refractaria/etiología , Epilepsia Refractaria/cirugía , Electrodos Implantados/efectos adversos , Epilepsia/terapia , Humanos , Estudios Multicéntricos como Asunto , Estudios Retrospectivos , Convulsiones/etiología , Resultado del Tratamiento , Adulto Joven
5.
Neurosurg Focus ; 52(4): E4, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35364581

RESUMEN

OBJECTIVE: Treatment of degenerative lumbar spine pathologies typically escalates to surgical intervention when symptoms begin to significantly impair patients' functional status. Currently, surgeons rely on subjective patient assessments through patient-reported outcome measures to estimate the decline in patient wellness and quality of life. In this analysis, the authors sought to use smartphone-based accelerometry data to provide an objective, continuous measurement of physical activity that might aid in effective characterization of preoperative functional decline in different lumbar spine surgical indications. METHODS: Up to 1 year of preoperative activity data (steps taken per day) from 14 patients who underwent lumbar decompression and 15 patients who underwent endoscopic lumbar fusion were retrospectively extracted from patient smartphones. A data-driven algorithm was constructed based on 10,585 unique activity data points to identify and characterize the functional decline of patients preceding surgical intervention. Algorithmic estimation of functional decline onset was compared with reported symptom onset in clinical documentation across patients who presented acutely (≤ 5 months of symptoms) or chronically (> 5 months of symptoms). RESULTS: The newly created algorithm identified a statistically significant decrease in physical activity during measured periods of functional decline (p = 0.0020). To account for the distinct clinical presentation phenotypes of patients requiring lumbar decompression (71.4% acute and 28.6% chronic) and those requiring lumbar fusion (6.7% acute and 93.3% chronic), a variable threshold for detecting clinically significant reduced physical activity was implemented. The algorithm characterized functional decline (i.e., acute or chronic presentation) in patients who underwent lumbar decompression with 100% accuracy (sensitivity 100% and specificity 100%), while characterization of patients who underwent lumbar fusion was less effective (accuracy 26.7%, sensitivity 21.4%, and specificity 100%). Adopting a less-permissive detection threshold in patients who underwent lumbar fusion, which rendered the algorithm robust to minor fluctuations above or below the chronically decreased level of preoperative activity in most of those patients, increased functional decline classification accuracy of patients who underwent lumbar fusion to 66.7% (sensitivity 64.3% and specificity 100%). CONCLUSIONS: In this study, the authors found that smartphone-based accelerometer data successfully characterized functional decline in patients with degenerative lumbar spine pathologies. The accuracy and sensitivity of functional decline detection were much lower when using non-surgery-specific detection thresholds, indicating the effectiveness of smartphone-based mobility analysis in characterizing the unique physical activity fingerprints of different lumbar surgical indications. The results of this study highlight the potential of using activity data to detect symptom onset and functional decline in patients, enabling earlier diagnosis and improved prognostication.


Asunto(s)
Teléfono Inteligente , Fusión Vertebral , Acelerometría , Descompresión Quirúrgica/métodos , Humanos , Calidad de Vida , Estudios Retrospectivos , Fusión Vertebral/métodos
6.
Biochemistry ; 59(15): 1493-1507, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-32251580

RESUMEN

Messenger RNA degradation is an important component of overall gene expression. During the final step of eukaryotic mRNA degradation, exoribonuclease 1 (Xrn1) carries out 5' → 3' processive, hydrolytic degradation of RNA molecules using divalent metal ion catalysis. To initiate studies of the 5' → 3' RNA decay machinery in our lab, we expressed a C-terminally truncated version of Saccharomyces cerevisiae Xrn1 and explored its enzymology using a second-generation, time-resolved fluorescence RNA degradation assay. Using this system, we quantitatively explored Xrn1's preference for 5'-monophosphorylated RNA substrates, its pH dependence, and the importance of active site mutations in the molecule's conserved catalytic core. Furthermore, we explore Xrn1's preference for RNAs containing a 5' single-stranded region both in an intermolecular hairpin structure and in an RNA-DNA hybrid duplex system. These results both expand and solidify our understanding of Xrn1, a centrally important enzyme whose biochemical properties have implications in numerous RNA degradation and processing pathways.


Asunto(s)
Exorribonucleasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Exorribonucleasas/química , Exorribonucleasas/genética , Concentración de Iones de Hidrógeno , Modelos Moleculares , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
7.
Epilepsy Behav ; 112: 107373, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32942207

RESUMEN

OBJECTIVES: The objective of the study were to examine the safety and efficacy of vagus nerve stimulation (VNS) for reducing seizure frequency and antiepileptic drugs (AEDs) in children younger than six years and to examine long-term VNS efficacy for children who receive the device at ages 1-3 and at ages 4-6. METHODS: We conducted a 10-year retrospective analysis of VNS implantations at UPMC Children's Hospital of Pittsburgh. Relevant data were collected within 12 months of VNS implantation and at six months, one, two, and four years after VNS implantation. RESULTS: This analysis included 99 patients ages 0-3 (n = 40) and 4-6 (n = 59) at first VNS implantation. Eighty-six patients followed up for ≥4 years. There were no significant differences between age at VNS implant (0-3 vs. 4-6) and seizure etiology or most seizure semiologies. Patients took an average of 3.01 ±â€¯1.29 AEDs prior to VNS and 3.84 ±â€¯1.68 AEDs at their latest follow-up. The overall response to VNS therapy (≥50% seizure reduction) at one year, two years, and four years after VNS implantation was 55%, 60%, and 52%, respectively. At two years, 59% of 0- to 3-year-old patients responded to VNS and 52% of 4- to 6-year-old patients responded to VNS. The overall major complication rate was 5.6%, consistent with VNS use for older age groups. SIGNIFICANCE: This study demonstrates the safety and efficacy of VNS for children with drug-resistant epilepsy (DRE) younger than six. One, two, and four years after VNS implantation, 55%, 60%, and 52% of these patients, respectively, achieved ≥50% reduction in seizure frequency. The safety of VNS is also comparable with older, better studied, age groups. Based on these data, VNS therapy should be considered for children younger than six.


Asunto(s)
Epilepsia , Preparaciones Farmacéuticas , Estimulación del Nervio Vago , Anciano , Niño , Preescolar , Epilepsia/terapia , Humanos , Lactante , Recién Nacido , Estudios Retrospectivos , Resultado del Tratamiento , Nervio Vago
8.
Kidney Blood Press Res ; 45(1): 70-83, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31896111

RESUMEN

INTRODUCTION: Furosemide reduces the glomerular filtration rate (GFR) and increases the renal vascular resistance (RVR) despite inhibiting tubuloglomerular feedback but increases proximal tubule pressure, renin release, and renal nerve activity. OBJECTIVE: This study tested the hypothesis that the fall in GFR with furosemide is due to volume depletion or activation of angiotensin type 1 (AT1) receptors or renal nerves. METHODS: Furosemide was infused for 60 min at 1.0 mg·kg-1·h-1 in groups of 5-8 anesthetized rats. Additional groups received intravenous volume replacement to prevent fluid and Na+ losses or volume replacement plus losartan or plus sham denervation or plus renal denervation or renal nerve deafferentation. RESULTS: At 60 min of infusion, furosemide alone reduced the GFR (-37 ± 4%; p < 0.01). This fall was not prevented by volume replacement or pretreatment with losartan, although losartan moderated the increase in RVR with furosemide (+44 ± 3 vs. +82 ± 7%; p < 0.01). Whereas the GFR fell after furosemide in rats after sham procedure (-31 ± 2%), it was not changed significantly after prior renal deafferentation. Proximal tubule pressure increased significantly but returned towards baseline over 60 min of furosemide, while urine output remained elevated, and GFR and renal blood flow depressed. CONCLUSIONS: The fall in GFR over 60 min of furosemide infusion is independent of volume depletion or activation of AT1 receptors but is largely dependent on renal afferent nerves.


Asunto(s)
Furosemida/uso terapéutico , Tasa de Filtración Glomerular/efectos de los fármacos , Infusiones Intravenosas/métodos , Riñón/inervación , Animales , Modelos Animales de Enfermedad , Furosemida/farmacología , Humanos , Ratas
9.
Pain Med ; 21(12): 3283-3291, 2020 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-32761129

RESUMEN

OBJECTIVE: Enhanced recovery after surgery (ERAS) pathways have previously been shown to be feasible and safe in elective spinal procedures. As publications on ERAS pathways have recently emerged in elective neurosurgery, long-term outcomes are limited. We report on our 18-month experience with an ERAS pathway in elective spinal surgery. METHODS: A historical cohort of 149 consecutive patients was identified as the control group, and 1,141 patients were prospectively enrolled in an ERAS protocol. The primary outcome was the need for opioid use one month postoperation. Secondary outcomes were opioid and nonopioid consumption on postoperative day (POD) 1, opioid use at three and six months postoperation, inpatient pain scores, patient satisfaction scores, postoperative Foley catheter use, mobilization/ambulation on POD0-1, length of stay, complications, and intensive care unit admissions. RESULTS: There was significant reduction in use of opioids at one, three, and six months postoperation (38.6% vs 70.5%, P < 0.001, 36.5% vs 70.9%, P < 0.001, and 23.6% vs 51.9%, P = 0.008) respectively. Both groups had similar surgical procedures and demographics. PCA use was nearly eliminated in the ERAS group (1.4% vs 61.6%, P < 0.001). ERAS patients mobilized faster on POD0 compared with control (63.5% vs 20.7%, P < 0.001). Fewer patients in the ERAS group required postoperative catheterization (40.7% vs 32.7%, P < 0.001). The ERAS group also had decreased length of stay (3.4 vs 3.9 days, P = 0.020). CONCLUSIONS: ERAS protocols for all elective spine and peripheral nerve procedures are both possible and effective. This standardized approach to patient care decreases opioid usage, eliminates the use of PCAs, mobilizes patients faster, and reduces length of stay.


Asunto(s)
Analgésicos Opioides , Recuperación Mejorada Después de la Cirugía , Analgésicos Opioides/uso terapéutico , Humanos , Tiempo de Internación , Dolor Postoperatorio/tratamiento farmacológico , Nervios Periféricos , Complicaciones Posoperatorias , Estudios Retrospectivos
10.
J Biomech Eng ; 142(6)2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31513714

RESUMEN

Occupational whole-body vibration (WBV) increases the risk of developing low back and neck pain; yet, there has also been an increased use of therapeutic WBV in recent years. Although the resonant frequency (fr) of the spine decreases as the exposure acceleration increases, effects of varying the vibration profile, including peak-to-peak displacement (sptp), root-mean-squared acceleration (arms), and frequency (f), on pain onset are not known. An established in vivo rat model of WBV was used to characterize the resonance of the spine using sinusoidal sweeps. The relationship between arms and fr was defined and implemented to assess behavioral sensitivity-a proxy for pain. Five groups were subjected to a single 30-min exposure, each with a different vibration profile, and a sham group underwent only anesthesia exposure. The behavioral sensitivity was assessed at baseline and for 7 days following WBV-exposure. Only WBV at 8 Hz induced behavioral sensitivity, and the higher arms exposure at 8 Hz led to a more robust pain response. These results suggest that the development of pain is frequency-dependent, but further research into the mechanisms leading to pain is warranted to fully understand which WBV profiles may be detrimental or beneficial.


Asunto(s)
Dolor , Vibración , Animales , Masculino , Ratas , Columna Vertebral
11.
Int J Gynecol Pathol ; 38(3): 230-240, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-29750700

RESUMEN

A chemotherapy response score (CRS) system was recently described to assess the histopathologic response and prognosis of patients with tubo-ovarian high-grade serous carcinoma (HGSC) receiving neoadjuvant chemotherapy. The current study was performed as an independent assessment of this CRS system. We retrospectively identified advanced stage HGSC patients who received neoadjuvant chemotherapy and underwent interval debulking. If available, a hemotoxylin and eosin slide from the omentum and the adnexa was selected for the study. Slides were independently scored by 13 pathologists using the 3-tiered CRS system. Reviewers then received web-based training and rescored the slides. Overall survival and progression-free survival were estimated using the Kaplan-Meier method and compared using the log-rank test. A total of 68 patients with omental (n=65) and/or adnexal (n=59) slides were included in the study. Interobserver reproducibility was moderate for omentum (κ, 0.48) and poor for adnexa (κ, 0.40), which improved for omentum (κ, 0.62) but not for adnexa (κ, 0.38) after online training. For omental slides, a consensus CRS of 1/2 was associated with a shorter median progression-free survival (10.9 mo; 95% confidence interval, 9-14) than a CRS of 3 (18.9 mo; 95% CI, 18-24; P=0.020). In summary, a 3-tiered CRS system of hemotoxylin and eosin-stained omental deposits can yield prognostic information for HGSC patients receiving neoadjuvant chemotherapy, and web-based training improved reproducibility but did not alter determination of clinical outcomes. The CRS system may allow oncologists to identify potential nonresponders and triage HGSC patients for heightened observation and/or clinical trials.


Asunto(s)
Carcinoma/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Anexos Uterinos/patología , Anexos Uterinos/cirugía , Anciano , Carcinoma/diagnóstico , Carcinoma/patología , Carcinoma/cirugía , Procedimientos Quirúrgicos de Citorreducción , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Terapia Neoadyuvante , Variaciones Dependientes del Observador , Epiplón/patología , Epiplón/cirugía , Sistemas en Línea , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
12.
Ultrastruct Pathol ; 43(1): 13-27, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30898001

RESUMEN

Perineal talc use is associated with ovarian carcinoma in many case-control studies. Such talc may migrate to pelvic organs and regional lymph nodes, with both clinical and legal significance. Our goal was to differentiate talc in pelvic lymph nodes due to exposure, versus contamination with talc in the laboratory. We studied 22 lymph nodes from ovarian tumor patients, some of which had documented talc exposure, to quantify talc using digestion of tissue taken from paraffin blocks and scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX). Talc particles correlated significantly with surface contamination assessments using polarized light microscopy. After adjusting for surface contamination, talc burdens in nodes correlated strongly with perineal talc use. In a separate group of lymph nodes, birefringent particles within the same plane of focus as the tissues in histological sections were highly correlated with talc particles within the tissue by in situ SEM/EDX (r = 0.80; p < 0.0001). We conclude that since talc can be a surface contaminant from tissue collection/preparation, digestion measurements may be influenced by contamination. Instead, because they preserve anatomic landmarks and permit identification of particles in cells and tissues, polarized light microscopy and in situ SEM/EDX are recommended to assess talc in lymph nodes.


Asunto(s)
Ganglios Linfáticos/patología , Microscopía Electrónica de Rastreo , Neoplasias Ováricas/patología , Estudios de Casos y Controles , Femenino , Humanos , Microscopía Electrónica de Rastreo/métodos , Microscopía de Polarización/métodos , Pelvis/patología
13.
Am J Physiol Renal Physiol ; 315(1): F74-F78, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29513072

RESUMEN

Nitric oxide prevents hypertension yet enhances proximal tubule Na+ reabsorption. Nitric oxide synthase is inhibited by asymmetric dimethylarginine (ADMA) that is metabolized by dimethylarginine dimethylaminohydrolase (DDAH) whose type 1 isoform is expressed abundantly in the proximal tubule (PT). We hypothesize that ADMA metabolized by DDAH-1 inhibits fluid reabsorbtion (Jv) by the proximal tubule. S2 segments of the PT were microperfused between blocks in vivo to assess Jv in anesthetized rats. Compared with vehicle, microperfusion of ADMA or Nω-nitro-l-arginine methyl ester (l-NAME) in the proximal tubule reduced Jv dose dependently. At 10-4 mol/l both reduced Jv by ~40% (vehicle: 3.2 ± 0.7 vs. ADMA: 2.1 ± 0.5, P < 0.01 vs. l-NAME: 1.9 ± 0.4 nl·min-1·mm-1, P < 0.01; n = 10). Selective inhibition of DDAH-1 in rats with intravenous L-257 (60 mg/kg) given 2 h before and L-257 (10-5 mol/l) perfused in the proximal tubule for 5 min reduced Jv by 32 ± 4% (vehicle: 3.2 ± 0.5 vs. L-257: 2.2 ± 0.5 nl·min-1·mm-1; P < 0.01) and increased plasma ADMA by ≈50% (vehicle: 0.46 ± 0.03 vs. L-257: 0.67 ± 0.03 µmol/l, P < 0.0001) without changing plasma symmetric dimethylarginine. Compared with nontargeted control small-interference RNA, knock down of DDAH-1 in mice by 60% with targeted small-interference RNAs (siRNA) reduced Jv by 29 ± 5% (nontargeted siRNA: 2.8 ± 0.20 vs. DDAH-1 knockdown: 1.9 ± 0.31 nl·min-1·mm-1, P < 0.05). In conclusion, fluid reabsorption in the proximal tubule is reduced by tubular ADMA or by blocking its metabolism by DDAH-1. L-257 is a novel regulator of proximal tubule fluid reabsorption.


Asunto(s)
Amidohidrolasas/metabolismo , Arginina/análogos & derivados , Túbulos Renales Proximales/enzimología , Reabsorción Renal , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/genética , Animales , Arginina/metabolismo , Arginina/farmacología , Inhibidores Enzimáticos/farmacología , Túbulos Renales Proximales/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Interferencia de ARN , Ratas Sprague-Dawley , Reabsorción Renal/efectos de los fármacos
14.
Am J Physiol Regul Integr Comp Physiol ; 314(3): R399-R406, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29167164

RESUMEN

Nuclear factor erythyroid factor 2 (Nrf2) transcribes genes in cultured endothelial cells that reduce reactive oxygen species (ROS) and generate nitric oxide (NO) or metabolize asymmetric dimethylarginine (ADMA), which inhibits NO synthase (NOS). Therefore, we undertook a functional study to test the hypothesis that activation of Nrf2 by tert-butylhydroquinone (tBHQ) preserves microvascular endothelial function during oxidative stress. Wild-type CB57BL/6 (wt), Nrf2 wt (+/+), or knockout (-/-) mice received vehicle (Veh) or tBHQ (0.1%; activator of Nrf2) during 14-day infusions of ANG II (to induce oxidative stress) or sham. MAP was recorded by telemetry. Mesenteric resistance arterioles were studied on isometric myographs and vascular NO and ROS by fluorescence microscopy. ANG II increased the mean arterial pressure (112 ± 5 vs. 145 ± 5 mmHg; P < 0.01) and excretion of 8-isoprostane F2α (2.8 ± 0.3 vs. 3.8 ± 0.3 ng/mg creatinine; P < 0.05) at 12-14 days. However, 12 days of ANG II reduced endothelium-derived relaxation (27 ± 5 vs. 17 ± 3%; P < 0.01) and NO (0.38 ± 0.07 vs. 0.18 ± 0.03 units; P < 0.01) but increased microvascular remodeling, endothelium-derived contractions (7.5 ± 0.5 vs. 13.0 ± 1.7%; P < 0.01), superoxide (0.09 ± 0.03 vs. 0.29 ± 0.08 units; P < 0.05), and contractions to U-46,619 (87 ± 6 vs. 118 ± 3%; P < 0.05), and endothelin-1(89 ± 4 vs. 123 ± 12%; P < 0.05). tBHQ prevented all of these effects of ANG II at 12-14 days in Nrf2+/+ mice but not in Nrf2-/- mice. In conclusion, tBHQ activates Nrf2 to prevent microvascular endothelial dysfunction, remodeling, and contractility, and moderate ADMA and hypertension at 12-14 days of ANG II infusion, thereby preserving endothelial function and preventing hypertension.


Asunto(s)
Angiotensina II , Antihipertensivos/farmacología , Arginina/análogos & derivados , Presión Arterial/efectos de los fármacos , Hidroquinonas/farmacología , Hipertensión/prevención & control , Microvasos/efectos de los fármacos , Factor 2 Relacionado con NF-E2/agonistas , Estrés Oxidativo/efectos de los fármacos , Animales , Arginina/sangre , Biomarcadores/sangre , Modelos Animales de Enfermedad , Factores Relajantes Endotelio-Dependientes/metabolismo , Hipertensión/inducido químicamente , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Microvasos/metabolismo , Microvasos/fisiopatología , Factor 2 Relacionado con NF-E2/deficiencia , Factor 2 Relacionado con NF-E2/genética , Óxido Nítrico/metabolismo , Transducción de Señal/efectos de los fármacos , Tromboxano B2/metabolismo , Factores de Tiempo , Regulación hacia Arriba , Remodelación Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos
15.
J Chem Inf Model ; 58(8): 1533-1543, 2018 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-30063345

RESUMEN

The majority of computational methods for predicting toxicity of chemicals are typically based on "nonmechanistic" cheminformatics solutions, relying on an arsenal of QSAR descriptors, often vaguely associated with chemical structures, and typically employing "black-box" mathematical algorithms. Nonetheless, such machine learning models, while having lower generalization capacity and interpretability, typically achieve a very high accuracy in predicting various toxicity endpoints, as unambiguously reflected by the results of the recent Tox21 competition. In the current study, we capitalize on the power of modern AI to predict Tox21 benchmark data using merely simple 2D drawings of chemicals, without employing any chemical descriptors. In particular, we have processed rather trivial 2D sketches of molecules with a supervised 2D convolutional neural network (2DConvNet) and demonstrated that the modern image recognition technology results in prediction accuracies comparable to the state-of-the-art cheminformatics tools. Furthermore, the performance of the image-based 2DConvNet model was comparatively evaluated on an external set of compounds from the Prestwick chemical library and resulted in experimental identification of significant and previously unreported antiandrogen potentials for several well-established generic drugs.


Asunto(s)
Aprendizaje Profundo , Descubrimiento de Drogas , Modelos Biológicos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/toxicidad , Algoritmos , Gráficos por Computador , Bases de Datos Farmacéuticas , Descubrimiento de Drogas/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Humanos , Modelos Químicos , Preparaciones Farmacéuticas/química
16.
J Environ Sci (China) ; 65: 162-170, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29548387

RESUMEN

This study assessed the effectiveness of three novel control technologies for particulate matter (PM) and volatile organic compound (VOC) removal from commercial meat cooking operations. All experiments were conducted using standardized procedures at University of California, Riverside's commercial test cooking facility. PM mass emissions collected using South Coast Air Quality Management District (SCAQMD) Method 5.1, as well as a dilution tunnel-based PM method showed statistically significantly reductions for each control technology when compared to baseline testing (i.e., without a catalyst). Overall, particle number emissions decreased with the use of control technologies, with the exception of control technology 2 (CT2), which is a grease removal technology based on boundary layer momentum transfer (BLMT) theory. Particle size distributions were unimodal with CT2 resulting in higher particle number populations at lower particle diameters. Organic carbon was the dominant PM component (>99%) for all experiments. Formaldehyde and acetaldehyde were the most abundant carbonyl compounds and showed reductions with the application of the control technologies. Some reductions in mono-aromatic VOCs were also observed with CT2 and the electrostatic precipitator (ESP) CT3 compared to the baseline testing.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Industria de Alimentos , Carne , Material Particulado/análisis
17.
Am J Physiol Renal Physiol ; 312(6): F1120-F1127, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28228405

RESUMEN

The Na+-K+-2Cl- cotransporter (NKCC2) on the loop of Henle is the site of action of furosemide. Because outer medullary potassium channel (ROMK) inhibitors prevent reabsorption by NKCC2, we tested the hypothesis that ROMK inhibition with a novel selective ROMK inhibitor (compound C) blocks tubuloglomerular feedback (TGF) and reduces vascular resistance. Loop perfusion of either ROMK inhibitor or furosemide caused dose-dependent blunting of TGF, but the response to furosemide was 10-fold more sensitive (IC50 = 10-6 M for furosemide and IC50 = 10-5 M for compound C). During systemic infusion, both diuretics inhibited TGF, but ROMK inhibitor was 10-fold more sensitive (compound C: 63% inhibition; furosemide: 32% inhibition). Despite blockade of TGF, 1 h of constant systemic infusion of both diuretics reduced the glomerular filtration rate (GFR) and renal blood flow (RBF) by 40-60% and increased renal vascular resistance (RVR) by 100-200%. Neither diuretic altered blood pressure or hematocrit. Proximal tubule hydrostatic pressures (PPT) increased transiently with both diuretics (compound C: 56% increase; furosemide: 70% increase) but returned to baseline. ROMK inhibitor caused more natriuresis (3,400 vs. 1,600% increase) and calciuresis (1,200 vs. 800% increase) but less kaliuresis (33 vs. 167% increase) than furosemide. In conclusion, blockade of ROMK or Na+-K+-2Cl- transport inhibits TGF yet increases renal vascular resistance. The renal vasoconstriction was independent of volume depletion, blood pressure, TGF, or PPT.


Asunto(s)
Diuréticos/farmacología , Glomérulos Renales/irrigación sanguínea , Glomérulos Renales/efectos de los fármacos , Túbulos Renales/irrigación sanguínea , Túbulos Renales/efectos de los fármacos , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/farmacología , Anestesia General , Animales , Calcio/orina , Relación Dosis-Respuesta a Droga , Retroalimentación , Furosemida/farmacología , Tasa de Filtración Glomerular/efectos de los fármacos , Presión Hidrostática , Glomérulos Renales/metabolismo , Túbulos Renales/metabolismo , Masculino , Modelos Animales , Natriuresis/efectos de los fármacos , Potasio/orina , Canales de Potasio de Rectificación Interna/metabolismo , Ratas Sprague-Dawley , Circulación Renal/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/farmacología , Miembro 1 de la Familia de Transportadores de Soluto 12/antagonistas & inhibidores , Miembro 1 de la Familia de Transportadores de Soluto 12/metabolismo , Resistencia Vascular/efectos de los fármacos
18.
Kidney Int ; 92(3): 625-633, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28396118

RESUMEN

Myogenic contractions protect kidneys from barotrauma but are impaired in chronic kidney disease (CKD). Since myogenic contractions are enhanced by superoxide but impaired by hydrogen peroxide, we tested the hypothesis that they are counterregulated by superoxide and H2O2 from NOX2/p47phox and/or NOX4/POLDIP2 in CKD. Myogenic contraction in isolated perfused afferent arterioles from mice with surgical 5/6 nephrectomy or sham operations fed a 6% sodium chloride diet was measured directly while superoxide and H2O2 were measured by fluorescence microscopy. Compared to sham-operated animals, an increase in perfusion pressure of arterioles from CKD mice doubled superoxide (21 versus 11%), increased H2O2 seven-fold (29 versus 4%), and reduced myogenic contractions profoundly (-1 versus -14%). Myogenic contractions were impaired further by PEG-superoxide dismutase or in arterioles from p47phox-/- (versus wild type) mice but became supra-normal by PEG-catalase or in mice with transgenic expression of catalase in vascular smooth muscle cells (-11 versus -1%). Single arterioles from mice with CKD expressed over 40% more mRNA and protein for NOX4 and POLDIP2. Myogenic responses in arterioles from POLDIP2 +/- (versus wild type) mice with CKD had over an 85% reduction in H2O2, but preserved superoxide and a normal myogenic response. Tempol administration to CKD mice for 3 months decreased afferent arteriolar superoxide and H2O2 and maintained myogenic contractions. Thus, afferent arteriolar superoxide generated by NOX2/p47phox opposes H2O2 generated by NOX4/POLDIP2 whose upregulation in afferent arterioles from mice with CKD accounts for impaired myogenic contractions.


Asunto(s)
Arteriolas/fisiopatología , Peróxido de Hidrógeno/metabolismo , Músculo Liso Vascular/patología , Insuficiencia Renal Crónica/patología , Superóxidos/metabolismo , Vasoconstricción/efectos de los fármacos , Animales , Arteriolas/enzimología , Catalasa/genética , Catalasa/metabolismo , Óxidos N-Cíclicos/farmacología , Modelos Animales de Enfermedad , Humanos , Riñón/irrigación sanguínea , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Fluorescente , Proteínas Mitocondriales/metabolismo , Músculo Liso Vascular/enzimología , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , NADPH Oxidasas/metabolismo , Proteínas Nucleares/metabolismo , Perfusión , Polietilenglicoles/metabolismo , Marcadores de Spin , Superóxido Dismutasa/metabolismo
19.
BMC Cancer ; 17(1): 422, 2017 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-28623900

RESUMEN

BACKGROUND: Ovarian cancer is the leading cause of death among gynecologic diseases in Western countries. We have previously identified a miR-200-E-cadherin axis that plays an important role in ovarian inclusion cyst formation and tumor invasion. The purpose of this study was to determine if the miR-200 pathway is involved in the early stages of ovarian cancer pathogenesis by studying the expression levels of the pathway components in a panel of clinical ovarian tissues, and fallopian tube tissues harboring serous tubal intraepithelial carcinomas (STICs), a suggested precursor lesion for high-grade serous tumors. METHODS: RNA prepared from ovarian and fallopian tube epithelial and stromal fibroblasts was subjected to quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR) to determine the expression of miR-200 families, target and effector genes and analyzed for clinical association. The effects of exogenous miR-200 on marker expression in normal cells were determined by qRT-PCR and fluorescence imaging after transfection of miR-200 precursors. RESULTS: Ovarian epithelial tumor cells showed concurrent up-regulation of miR-200, down-regulation of the four target genes (ZEB1, ZEB2, TGFß1 and TGFß2), and up-regulation of effector genes that were negatively regulated by the target genes. STIC tumor cells showed a similar trend of expression patterns, although the effects did not reach significance because of small sample sizes. Transfection of synthetic miR-200 precursors into normal ovarian surface epithelial (OSE) and fallopian tube epithelial (FTE) cells confirmed reduced expression of the target genes and elevated levels of the effector genes CDH1, CRB3 and EpCAM in both normal OSE and FTE cells. However, only FTE cells had a specific induction of CA125 after miR-200 precursor transfection. CONCLUSIONS: The activation of the miR-200 pathway may be an early event that renders the OSE and FTE cells more susceptible to oncogenic mutations and histologic differentiation. As high-grade serous ovarian carcinomas (HGSOC) usually express high levels of CA125, the induction of CA125 expression in FTE cells by miR-200 precursor transfection is consistent with the notion that HGSOC has an origin in the distal fallopian tube.


Asunto(s)
Carcinoma in Situ/genética , Cistadenocarcinoma Seroso/genética , Trompas Uterinas/patología , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Ováricas/genética , Biomarcadores de Tumor , Carcinoma in Situ/patología , Línea Celular Tumoral , Cistadenocarcinoma Seroso/patología , Femenino , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Clasificación del Tumor , Estadificación de Neoplasias , Especificidad de Órganos/genética , Neoplasias Ováricas/patología , Interferencia de ARN , ARN Mensajero/genética
20.
Environ Sci Technol ; 51(3): 1868-1875, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28050905

RESUMEN

Ocean going vessels (OGVs) operating within emission control areas (ECA) are required to use fuels with ≤0.1 wt % sulfur. Up to now only distillate fuels could meet the sulfur limits. Recently refiners created a novel low-sulfur heavy-fuel oil (LSHFO) meeting the sulfur limits so questions were posed whether nitric oxide (NOx) and particulate matter (PM) emissions were the same for the two fuels. This project characterized criteria pollutants and undertook a detailed analysis of PM emissions from a very large crude oil carrier (VLCC) using a distillate ECA fuel (MGO) and novel LSHFO. Results showed emission factors of NOx were ∼5% higher with MGO than LSHFO. PM2.5 emission factors were ∼3 times higher with LSHFO than MGO, while both were below values reported by Lloyds, U.S. EPA and CARB. A detailed analysis of PM revealed it was >90% organic carbon (OC) for both fuels. Elemental carbon (EC) and soot measured with an AVL microsoot sensor (MSS) reflected black carbon. PM size distributions showed unimodal peaks for both MGO (20-30 nm) and LSHFO (30-50 nm). Particle number (PN) emissions were 28% and 17% higher with the PPS-M compared to the SMPS for LSHFO and MGO, respectively.


Asunto(s)
Contaminantes Atmosféricos , Aceites Combustibles , Contaminación del Aire , Tamaño de la Partícula , Material Particulado , Hollín , Emisiones de Vehículos
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