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1.
Am J Physiol Renal Physiol ; 326(3): F460-F476, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38269409

RESUMEN

Kidney-specific with-no-lysine kinase 1 (KS-WNK1) is an isoform of WNK1 kinase that is predominantly found in the distal convoluted tubule of the kidney. The precise physiological function of KS-WNK1 remains unclear. Some studies have suggested that it could play a role in regulating potassium renal excretion by modulating the activity of the Na+-Cl- cotransporter (NCC). However, changes in the potassium diet from normal to high failed to reveal a role for KS-WNK1, but under a normal-potassium diet, the expression of KS-WNK1 is negligible. It is only detectable when mice are exposed to a low-potassium diet. In this study, we investigated the role of KS-WNK1 in regulating potassium excretion under extreme changes in potassium intake. After following a zero-potassium diet (0KD) for 10 days, KS-WNK1-/- mice had lower plasma levels of K+ and Cl- while exhibiting higher urinary excretion of Na+, Cl-, and K+ compared with KS-WNK1+/+ mice. After 10 days of 0KD or normal-potassium diet (NKD), all mice were challenged with a high-potassium diet (HKD). Plasma K+ levels markedly increased after the HKD challenge only in mice previously fed with 0KD, regardless of genotype. KSWNK1+/+ mice adapt better to HKD challenge than KS-WNK1-/- mice after a potassium-retaining state. The difference in the phosphorylated NCC-to-NCC ratio between KS-WNK1+/+ and KS-WNK1-/- mice after 0KD and HKD indicates a role for KS-WNK1 in both NCC phosphorylation and dephosphorylation. These observations show that KS-WNK1 helps the distal convoluted tubule to respond to extreme changes in potassium intake, such as those occurring in wildlife.NEW & NOTEWORTHY The findings of this study demonstrate that kidney-specific with-no-lysine kinase 1 plays a role in regulating urinary electrolyte excretion during extreme changes in potassium intake, such as those occurring in wildlife. .


Asunto(s)
Ratones Noqueados , Potasio en la Dieta , Proteína Quinasa Deficiente en Lisina WNK 1 , Animales , Masculino , Ratones , Riñón/metabolismo , Túbulos Renales Distales/metabolismo , Ratones Endogámicos C57BL , Fosforilación , Potasio/orina , Potasio/metabolismo , Potasio/sangre , Potasio en la Dieta/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Eliminación Renal , Miembro 3 de la Familia de Transportadores de Soluto 12/metabolismo , Miembro 3 de la Familia de Transportadores de Soluto 12/genética , Proteína Quinasa Deficiente en Lisina WNK 1/metabolismo , Proteína Quinasa Deficiente en Lisina WNK 1/genética , Femenino
2.
Appl Opt ; 63(2): 467-482, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38227244

RESUMEN

The evaluation of high-speed camera image sequence analysis results in concrete material testing under high-impact loading necessitates the consideration of the effect of the image quality on the measurement accuracy and thus on the potential of the geometric measurements derived from the image sequences. In this contribution, we evaluate the application potential of three ultrahigh-speed cameras with frame rates up to 10 Mfps to analyze the deformation of concrete specimens before and after main crack formation in bending and compression tests. Specifically, we evaluate the Kirana 7M and Shimadzu HPV-X2 cameras with ISIS sensor architecture, and the Phantom TMX 7510 camera with BSI CMOS sensor technology. Three-point bending tests and split-Hopkinson pressure bar tests are performed on 160×40×40m m 3 cuboids and on 80 mm long, 50 mm diameter cylinders. Prior to main crack formation, the displacement vector field represents the specimen deformation, with higher values indicating the position where main cracks will initiate and propagate. Deformations of 80 µm in 54 µs for a bending test and of 154 µm in 36.67 µs for a compression test could be measured. The main cracks are then detected using displacement vector field discontinuity analysis techniques, and their evolution is followed to estimate the crack propagation velocity. Average velocities in bending tests between 603 and 854 m/s have been determined over a time interval up to 40 µs. An investigation of the camera sensor operation of the three optical devices is presented to assess their suitability for deformation analysis. Laboratory tests and real experimental results show that the quality of the propagation vector field, the crack detection, and the crack tip tracking are obviously affected by the image quality, but more significantly by the spatial and temporal resolution due to the small relative step deformations.

3.
Sensors (Basel) ; 23(4)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36850759

RESUMEN

In the context of setting up a stereo high-speed camera system for accurate 3D measurements in highly dynamic experiments, the potential of a "Fastcam SA-X2" stereo system is evaluated by testing different camera configurations and motion scenarios. A thorough accuracy analysis is performed using spatial rigid-body transformations and relative measurement analyses of photogrammetrically reconstructed surfaces of nondeformable objects. The effects of camera calibration, exposure time, object velocity, and object surface pattern quality on the quality of adjusted 3D coordinates are taken into consideration. While the exposure time does not significantly influence the quality of the static measurements, the results of dynamic experiments demonstrate that not only an insufficient frame rate but also an increased noise level resulting from short exposure times affects 3D coordinate accuracy. Using appropriate configurations to capture dynamic events, the errors in dynamic experiments do not differ significantly from the errors obtained in static measurements. A spatial mapping error of less than 1 µm is obtained through the experiments, with proper testing configurations for an object surface area of 5×20 mm. These findings are relevant for users of high-speed stereo imaging techniques to perform geometric 3D measurements, deformation, and crack analyses.

4.
J Clin Psychiatry ; 84(6)2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37870364

RESUMEN

Objective: To compare clinical and functional variables among 3 groups of children and adolescents: subjects at clinical high risk for psychosis (CHR-P) who also have obsessive-compulsive symptoms (OCS), CHR-P patients without OCS, and healthy controls (HC).Methods: A total of 128 CHR-P patients and 98 HC between the ages of 10 and 17 years were recruited as part of a multicenter prospective longitudinal study conducted in Spain between January 1, 2011, and December 31, 2018, with diagnoses made for CHR-P using the Scale of Prodromal Symptoms (SOPS). Two groups were obtained based on Leyton Obsessional Inventory-Child Version (LOI-CV) scores: 64 CHR-P patients with OCS (OCS+) and 64 CHR-P patients without OCS (OCS-). Clinical variables were analyzed with a generalized linear model.Results: Overall, 128 CHR-P patients, 64 (50%) with OCS (mean ± SD age = 15.5 ± 1.4 years, 34.4% male), 64 CHR-P patients without OCS (mean ± SD age = 15.1 ± 1.9 years, 34.4% male), and 98 HC (mean ± SD age = 15.5 ± 1.5 years, 42.9% male), of whom 19 (19.5%) had OCS, were included. Generalized linear model analysis revealed significant differences between the groups. The OCS+ group showed more severe prodromal symptoms (P = .007), worse functioning at baseline (P = .044) and during the previous year (P = .004), and more dysmorphophobic symptoms (P < .001) compared to the OCS- group. OCS+ patients were also more frequently treated with antidepressants (P = .004) than were OCS- patients.Conclusions: In our sample, among children and adolescents with CHR-P, the prevalence of OCS was high (50%). OCS+ subjects had a more severe clinical and functional profile than OCS- subjects. Early detection and treatment of these symptoms can lead to better outcomes for these patients.


Asunto(s)
Trastorno Obsesivo Compulsivo , Trastornos Psicóticos , Humanos , Masculino , Adolescente , Niño , Femenino , Estudios Longitudinales , Estudios Prospectivos , Síntomas Prodrómicos , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Trastorno Obsesivo Compulsivo/diagnóstico , Trastorno Obsesivo Compulsivo/epidemiología
5.
Environ Sci Pollut Res Int ; 27(28): 35712-35723, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32601876

RESUMEN

Dissolved organic matter (DOM) will be increasingly monitored by means of in situ fluorescence spectroscopy devices in order to supervise wastewater treatment plant efficiency, due to their ease of implementation and high-frequency measurement capacity. However, fluorescence spectroscopy measurements are reported to be sensitive to the sample matrix effects of temperature, the inner filter effect (IFE), and turbidity. Matrix effect estimation tests and signal correction have been developed for DOM (tyrosine-like, tryptophan-like, and humic substances-like fluorescent compounds) fluorescence measurements in unfiltered urban sewage samples. All such tests are conducted in temperature, absorbance, and turbidity ranges representative of urban sewage. For all fluorophores studied, an average of 1% fluorescence intensity decrease per degree (°C) of temperature increase could be observed. Protein-like fluorescent compound signals were found to be significantly affected by turbidity (0 to 210 NTU) and IFE (absorbance 254 nm > 0.200). Only temperature needs to be corrected for humic substances-like fluorescent compounds since other effects were not observed over the studied ranges of absorbance and turbidity. The fluorescence intensity correction method was applied first to each matrix effect separately and then combined by using a sequential mathematical correction methodology. An efficient methodology for determining the matrix effect correction equations for DOM fluorescence analysis into unfiltered urban sewage samples has been highlighted and could be used for in situ fluorescence measurement devices.


Asunto(s)
Sustancias Húmicas/análisis , Aguas del Alcantarillado , Espectrometría de Fluorescencia , Temperatura , Aguas Residuales
6.
Otol Neurotol ; 28(6): 798-800, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17721367

RESUMEN

OBJECTIVE: To analyze the time course of caloric response in patients with Benign Paroxysmal Positional Vertigo (BPPV). PATIENTS: Seventy-four individuals with diagnosis of BPPV during Dix-Hallpike (DH) test. STUDY DESIGN: A prospective, longitudinal study. SETTING: A tertiary referral center. INTERVENTION: Patients were treated by particle repositioning maneuvers according to the affected canal, and the effectiveness was evaluated at 180 and 360 days. Bithermal caloric response was obtained by using 44 and 30 degrees C water irrigations at diagnosis, 6 months, and 1 year after. MAIN OUTCOME MEASURE: Canal paresis (CP) and response to DH after treatment. RESULTS: The effectiveness of the treatment for BPPV (absence of vertigo and positional nystagmus during DH) was 65.2% (45 of 69) after 1 year of follow-up. Twenty-five percent of (16 of 64) individuals with BPPV presented CP at diagnosis, 27% (12 of 44) at 6 months, and 16% (9 of 56) 1 year after. One year after, seven individuals with CP showed a normal caloric response, another seven demonstrated persistent CP, and one case developed a bilateral CP. The effectiveness of particle repositioning maneuvers was not significantly different between subjects with or without CP after 1 year of follow-up (odds ratio, 1.31 [95% confidence intervals, 0.35-4.89], p = 0.88). CONCLUSION: Canal paresis is not associated with a lower outcome to repositioning.


Asunto(s)
Pruebas Calóricas , Vértigo/diagnóstico , Anciano , Audiometría de Tonos Puros , Conducto Auditivo Externo/patología , Conducto Auditivo Externo/cirugía , Movimientos Oculares/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Nistagmo Fisiológico/fisiología , Procedimientos Quirúrgicos Otológicos , Paresia/patología , Resultado del Tratamiento , Vértigo/cirugía , Vértigo/terapia
7.
Am J Rhinol Allergy ; 28(3): 232-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24980234

RESUMEN

BACKGROUND: Two different allergic rhinitis (AR) symptom phenotype classifications exist. Treatment recommendations are based on intermittent-persistent (INT-PER) cataloging, but clinical trials still use the former seasonal AR-perennial AR (SAR-PAR) classification. This study was designed to describe how INT-PER, mild-moderate/severe and SAR-PAR of patients seen by allergists are distributed over the different climate zones in a (sub)tropical country and how these phenotypes relate to allergen sensitization patterns. METHODS: Six climate zones throughout Mexico were determined, based on National Geographic Institute (Instituto Nacional de Estadística y Geografía) data. Subsequent AR patients (2-68 years old) underwent a blinded, standardized skin-prick test and filled out a validated questionnaire phenotyping AR. RESULTS: Five hundred twenty-nine subjects participated in this study. In the tropical zone with 87% house-dust mite sensitization, INT (80.9%; p < 0.001) and PAR (91%; p = 0.04) were more frequent than in the subtropics. In the central high-pollen areas, there was less moderate/severe AR (65.5%; p < 0.005). Frequency of comorbid asthma showed a clear north-south gradient, from 25% in the dry north to 59% in the tropics (p < 0.005). No differences exist in AR cataloging among patients with different sensitization patterns, with two minor exceptions (more PER in tree sensitized and more PAR in mold positives; p < 0.05). CONCLUSION: In a (sub)tropical country the SAR-PAR classification seems of limited value and bears poor relation with the INT-PER classification. INT is more frequent in the tropical zone. Because PER has been shown to relate to AR severity, clinical trials should select patients based on INT-PER combined with the severity cataloging because these make for a better treatment guide than SAR-PAR.


Asunto(s)
Asma/clasificación , Rinitis Alérgica/clasificación , Adolescente , Adulto , Alérgenos/inmunología , Asma/epidemiología , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Geografía Médica/estadística & datos numéricos , Humanos , Masculino , México , Persona de Mediana Edad , Fenotipo , Rinitis Alérgica/epidemiología , Estaciones del Año , Clima Tropical , Adulto Joven
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