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1.
Phys Chem Chem Phys ; 26(26): 17991-17998, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38764355

RESUMEN

The photo-induced dynamics of o-nitrophenol, particularly its photolysis, has garnered significant scientific interest as a potential source of nitrous acid in the atmosphere. Although the photolysis products and preceding photo-induced electronic structure dynamics have been investigated extensively, the nuclear dynamics accompanying the non-radiative relaxation of o-nitrophenol on the ultrafast timescale, which include an intramolecular proton transfer step, have not been experimentally resolved. Herein, we present a direct observation of the ultrafast nuclear motions mediating photo-relaxation using ultrafast electron diffraction. This work spatiotemporally resolves the loss of planarity which enables access to a conical intersection between the first excited state and the ground state after the proton transfer step, on the femtosecond timescale and with sub-Angstrom resolution. Our observations, supported by ab initio multiple spawning simulations, provide new insights into the proton transfer mediated relaxation mechanism in o-nitrophenol.

2.
J Chem Phys ; 161(9)2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39225516

RESUMEN

This second paper in a series of two describes the chirped-pulse ice apparatus that permits the detection of buffer gas cooled molecules desorbed from an energetically processed ice using broadband mm-wave rotational spectroscopy. Here, we detail the lower ice stage developed to generate ices at 4 K, which can then undergo energetic processing via UV/VUV photons or high-energy electrons and which ultimately enter the gas phase via temperature-programmed desorption (TPD). Over the course of TPD, the lower ice stage is interfaced with a buffer gas cooling cell that allows for sensitive detection via chirped-pulse rotational spectroscopy in the 60-90 GHz regime. In addition to a detailed description of the ice component of this apparatus, we show proof-of-principle experiments demonstrating the detection of H2CO products formed through irradiation of neat methanol ices or 1:1 CO + CH4 mixed ices.

3.
Med J Malaysia ; 79(Suppl 1): 140-147, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38555899

RESUMEN

INTRODUCTION: Vision screening has been initiated to detect potential vision problems, paving referral pathways towards a full eye examination. Time-cost-labour practicality challenges of equipment-based vision screening have lingered for decades. Going for the highest sensitivity and specificity or opting for a pragmatic and affordable vision screening program remains a dilemma in public eye health. We aimed to report the development of a new online and equipment-free vision screening called Eye: Questionnairebased Vision Screening (EyeQVS). We also analysed the visual profile of Orang Bateq resided in a remote locality, using findings from EyeQVS, single test vision screening and full eye examination. MATERIALS AND METHODS: Multi-perspective development strategies were employed in designing EyeQVS. The questionnaire items were constructed using the working backward technique, compiling common vision disorders from the literature and face validation using expert panels. Face validation and usability assessment were performed on EyeQVS. The vision screening was carried out using EyeQVS and single test visual acuity screening method. The full eye examination included visual acuity, refraction, binocular vision and ocular health assessment. The visual profile of indigenous people (Orang Bateq) at Kampung Bengoi and Kampung Atok, Jerantut, Pahang was analysed using EyeQVS, single test visual acuity screening method and full eye examination. RESULTS: The performance of EyeQVS was affirmative in both face validation and usability. About 95% of Orang Bateq failed full eye examination, while 55% failed EyeQVS screening. None of them failed single test vision screening. Binocular disorders and dry eye problems were commonly found in Orang Bateq. EyeQVS unearthed more various vision problems compared to the single test vision screening (visual acuity alone) as a screening tool in a remote location. CONCLUSION: EyeQVS can screen for binocular disorders and dry eyes problem commonly found among indigenous people, which might be missed using a single-test visual acuity screening approach. EyeQVS is a practical alternative for vision screening in places where financial or location hinders eye healthcare access.


Asunto(s)
Selección Visual , Humanos , Selección Visual/métodos , Interfaz Usuario-Computador , Trastornos de la Visión , Agudeza Visual , Tamizaje Masivo
4.
Am J Kidney Dis ; 81(3): 329-335, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36241009

RESUMEN

RATIONALE & OBJECTIVE: Clonal hematopoiesis of indeterminate potential (CHIP), defined by the age-related ontogenesis of expanded leukemogenic variants indicative of a genetically distinct clonal leukocyte population, is associated with risk of hematologic malignancy and cardiovascular disease. In experimental models, recapitulation of CHIP promotes kidney interstitial fibrosis with direct tissue infiltration of donor macrophages. We tested the hypothesis that CHIP is associated with kidney function decline in the general population. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: 12,004 individuals from 3 community-based cohorts in the TOPMed Consortium. EXPOSURE: CHIP status from whole-genome sequences obtained from DNA extracted from peripheral blood. OUTCOME: Risk of 30% decline in estimated glomerular filtration rate (eGFR) and percent eGFR decline per year during the follow-up period. ANALYTICAL APPROACH: Cox proportional hazards models for 30% eGFR decline end point and generalized estimating equations for annualized relative change in eGFR with meta-analysis. Study-specific estimates were combined using fixed-effect meta-analysis. RESULTS: The median baseline eGFR was 84mL/min/1.73m2. The prevalence of CHIP was 6.6%, 9.0%, and 12.2% in persons aged 50-60, 60-70, and>70 years, respectively. Over a median follow-up period of 8 years, for the 30% eGFR outcome 205 events occurred among 1,002 CHIP carriers (2.1 events per 100 person-years) and 2,041 events in persons without CHIP (1.7 events per 100 person-years). In meta-analysis, CHIP was associated with greater risk of a 30% eGFR decline (17% [95% CI, 1%-36%] higher; P=0.04). Differences were not observed between those with baseline eGFR above or below 60mL/min/1.73m2, of age above or below 60 years, or with or without diabetes. LIMITATIONS: Small number of participants with moderate-to-advanced kidney disease and restricted set of CHIP driver variants. CONCLUSIONS: We report an association between CHIP and eGFR decline in 3 general population cohorts without known kidney disease. Further studies are needed to investigate this novel condition and its potential impact among individuals with overt kidney disease.


Asunto(s)
Fallo Renal Crónico , Insuficiencia Renal Crónica , Humanos , Estudios de Cohortes , Hematopoyesis Clonal , Riñón , Fallo Renal Crónico/epidemiología , Tasa de Filtración Glomerular , Insuficiencia Renal Crónica/epidemiología , Progresión de la Enfermedad
5.
Eur Heart J ; 43(17): 1668-1680, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35245370

RESUMEN

AIMS: Mitral valve prolapse (MVP) is a common valvular heart disease with a prevalence of >2% in the general adult population. Despite this high incidence, there is a limited understanding of the molecular mechanism of this disease, and no medical therapy is available for this disease. We aimed to elucidate the genetic basis of MVP in order to better understand this complex disorder. METHODS AND RESULTS: We performed a meta-analysis of six genome-wide association studies that included 4884 cases and 434 649 controls. We identified 14 loci associated with MVP in our primary analysis and 2 additional loci associated with a subset of the samples that additionally underwent mitral valve surgery. Integration of epigenetic, transcriptional, and proteomic data identified candidate MVP genes including LMCD1, SPTBN1, LTBP2, TGFB2, NMB, and ALPK3. We created a polygenic risk score (PRS) for MVP and showed an improved MVP risk prediction beyond age, sex, and clinical risk factors. CONCLUSION: We identified 14 genetic loci that are associated with MVP. Multiple analyses identified candidate genes including two transforming growth factor-ß signalling molecules and spectrin ß. We present the first PRS for MVP that could eventually aid risk stratification of patients for MVP screening in a clinical setting. These findings advance our understanding of this common valvular heart disease and may reveal novel therapeutic targets for intervention.


Asunto(s)
Prolapso de la Válvula Mitral , Adulto , Sitios Genéticos/genética , Estudio de Asociación del Genoma Completo , Humanos , Proteínas de Unión a TGF-beta Latente/genética , Prolapso de la Válvula Mitral/genética , Proteómica , Factores de Riesgo
6.
Infect Immun ; 89(9): e0018721, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-33941577

RESUMEN

The gut microbiome orchestrates epithelial homeostasis and both local and remote immunological responses. Critical to these regulatory interactions are innate immune receptors termed Toll-like receptors (TLRs). Studies to date have implicated innate immunity and Toll-like receptors in shaping key features of the gut microbiome. However, a variety of biological and environmental variables are also implicated in determining gut microbiota composition. In this report, we hypothesized that cohousing and environment dominated the regulation of the gut microbiota in animal models independent of innate immunity. To determine the importance of these variables, innate immunity, or environment in shaping gut microbiota, we used a randomized cohousing strategy and transgenic TLR-deficient mice. We have found that mice cohoused together by genotype exhibited limited changes over time in the composition of the gut microbiota. However, for mice randomized to cage, we report extensive changes in the gut microbiota, independent of TLR function, whereby the fecal microbiota of TLR-deficient mice converges with that of wild-type mice. TLR5-deficient mice in these experiments exhibit greater susceptibility to comparative changes in the microbiota than other TLR-deficient mice and wild-type mice. Our work has broad implications for the study of innate immunity and host-microbiota interactions. Given the profound impact that gut dysbiosis may have on immunity, this report highlights the potential impact of cohousing on the gut microbiota and indices of inflammation as outcomes in biological models of infectious or inflammatory disease.


Asunto(s)
Microbioma Gastrointestinal , Homeostasis , Interacciones Microbiota-Huesped , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Receptores Toll-Like/metabolismo , Animales , Susceptibilidad a Enfermedades , Disbiosis , Inmunidad Innata , Inmunidad Mucosa , Ratones , Modelos Animales
7.
Proc Biol Sci ; 288(1950): 20210130, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33975470

RESUMEN

The future of coral reef ecosystems is under threat because vital reef-accreting species such as coralline algae are highly susceptible to ocean acidification. Although ocean acidification is known to reduce coralline algal growth rates, its direct effects on the development of coralline algal reproductive structures (conceptacles) is largely unknown. Furthermore, the long-term, multi-generational response of coralline algae to ocean acidification is extremely understudied. Here, we investigate how mean pH, pH variability and the pH regime experienced in their natural habitat affect coralline algal conceptacle abundance and size across six generations of exposure. We show that second-generation coralline algae exposed to ocean acidification treatments had conceptacle abundances 60% lower than those kept in present-day conditions, suggesting that conceptacle development is initially highly sensitive to ocean acidification. However, this negative effect of ocean acidification on conceptacle abundance disappears after three generations of exposure. Moreover, we show that this transgenerational acclimation of conceptacle development is not facilitated by a trade-off with reduced investment in growth, as higher conceptacle abundances are associated with crusts with faster growth rates. These results indicate that the potential reproductive output of coralline algae may be sustained under future ocean acidification.


Asunto(s)
Rhodophyta , Agua de Mar , Aclimatación , Arrecifes de Coral , Ecosistema , Concentración de Iones de Hidrógeno , Océanos y Mares
8.
Br J Dermatol ; 182(1): 24-28, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31025310

RESUMEN

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory condition that can have periodic worsening or flares. Measurement of flare is important because it can inform treatment efficacy; however, it is unclear how HS flare should be defined. OBJECTIVES: This study reviewed the literature for definitions of HS flare. METHODS: The PubMed MEDLINE online database was searched on 10 January 2018 and the search was repeated on 8 December 2018 for new publications. Titles and abstracts were screened for inclusion. Subsequently, full articles were screened for inclusion. Papers were included if the publication was a systematic review, clinical trial, cohort study, case report or series, or cross-sectional study. Studies were excluded if they were journalistic reviews, did not discuss clinical findings of HS or did not use the words 'flare', 'exacerbation', 'relapse' or 'recurrence'. RESULTS: Two hundred and seventy-four papers were identified and 154 fulfilled the study criteria. Of these, 27 (17.5%) included the term 'flare' and 16 (10.4%) included the term 'exacerbation'. Two of the 27 papers (7%) defined the term flare and both included patient report of changes in symptoms or signs. One of 16 papers (6%) defined exacerbation, which was taken as one new HS lesion. The terms 'recurrence' and 'relapse' were more apt to be defined: 13% (13 of 100) and 14% (six of 44), respectively. CONCLUSIONS: The lack of a specific and measurable definition of HS flare is a barrier to assessment of this important outcome. Once a specific and measurable definition is established, validated and reliable measures of HS flare can be incorporated into future studies. What's already known about this topic? Hidradenitis suppurativa (HS) is a chronic, relapsing inflammatory skin condition. The ability to assess flares is important to people who have HS; however, it is unclear how this is defined. HS flare is one of the core outcomes in the core outcome set for HS clinical trials; however, it is unclear how this should be assessed. What does this study add? This literature review reveals the paucity of measurable definitions associated with the use of the term 'flare' in the HS literature. It also highlights the variation and lack of a validated and reliable measure of HS flare.


Asunto(s)
Hidradenitis Supurativa , Estudios de Cohortes , Estudios Transversales , Hidradenitis Supurativa/diagnóstico , Humanos , Recurrencia , Resultado del Tratamiento
9.
Physiol Genomics ; 51(3): 90-96, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30707046

RESUMEN

Acute kidney injury (AKI) is an increasing clinical problem that is associated with chronic kidney disease progression. Cannabinoid receptor 2 (CB2) activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described. In this study, we investigated the effects of our novel CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion with laser Doppler flowmetry and changes in luminal diameter with isolated afferent arterioles. In this study, intravenously infused SMM-295 (6 mg/kg) significantly increased cortical renal perfusion (13.8 ± 0.6%; P < 0.0001; n = 7) compared with vehicle (0.1 ± 1.5%; n = 10) normalized to baseline values in anesthetized C57BL/6J mice. This effect was not dependent upon activation of the CB1 receptor (met-anandamide; 6 mg/kg iv) and was predominantly abolished in Cnr2 knockout mice with SMM-295 (6 mg/kg iv). Ablation of the renal afferent nerves with capsaicin blocked the SMM-295-dependent increase in renal cortical perfusion, and the increased renal blood flow was not dependent upon products synthesized by cyclooxygenase or nitric oxide synthase. The increased renal perfusion by CB2 receptor activation is also attributed to a direct vascular effect, since SMM-295 (5 µM) engendered a significant 37 ± 7% increase ( P < 0.0001; n = 4) in luminal diameters of norepinephrine-preconstricted afferent arterioles. These data provide new insight into the potential benefit of SMM-295 by activating vascular and nonvascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/metabolismo , Receptor Cannabinoide CB2/agonistas , Receptor Cannabinoide CB2/metabolismo , Circulación Renal/efectos de los fármacos , Vasodilatadores/uso terapéutico , Animales , Ácidos Araquidónicos/administración & dosificación , Ácidos Araquidónicos/uso terapéutico , Agonistas de Receptores de Cannabinoides/administración & dosificación , Agonistas de Receptores de Cannabinoides/uso terapéutico , Modelos Animales de Enfermedad , Endocannabinoides/administración & dosificación , Endocannabinoides/uso terapéutico , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Técnicas de Inactivación de Genes , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Óxido Nítrico Sintasa/metabolismo , Alcamidas Poliinsaturadas/administración & dosificación , Alcamidas Poliinsaturadas/uso terapéutico , Prostaglandina-Endoperóxido Sintasas/metabolismo , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/genética , Vasodilatación/efectos de los fármacos , Vasodilatadores/administración & dosificación
10.
Surg Endosc ; 33(8): 2456-2458, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30327914

RESUMEN

BACKGROUND: The true incidence of occult contralateral inguinal hernia is unknown; however, when found, there exists controversy as to whether or not they should be repaired. The aim of our study is to identify the incidence of contralateral incidental inguinal hernias in our surgical population, compare our results to previous studies timelining occult hernia identification to repair need, and generate debate as to whether incidental contralateral hernias should be repaired at the index operation. METHODS: We reviewed the charts of 297 consecutive patients undergoing robotic inguinal hernia repair between October 2014 and April 2018 at a single facility. By comparing preoperative physical examination to intraoperative findings, we determined the number of occult contralateral inguinal hernias in our patient population. RESULTS: Of 297 patients, 158 (53.2%) presented with a right inguinal hernia, 90 (30.3%) presented with a left inguinal hernia, and 49 (16.5%) presented with bilateral inguinal hernias. Forty-seven of the 297 patients (15.8%) were found to have an incidental contralateral inguinal hernia. Excluding patients with known bilateral inguinal hernias, 20% of patients with a left inguinal hernia were found to have an occult right inguinal hernia and 18.4% of patients with a right inguinal hernia were found to have an occult left inguinal hernia. CONCLUSIONS: The true incidence of occult contralateral inguinal hernia may be higher than originally thought. When inguinal hernia repair is performed through a transabdominal approach, these occult hernias may be easily addressed during the same operation without additional skin incisions. This may ultimately prevent the morbidity of developing a metachronous hernia that requires repair.


Asunto(s)
Hernia Inguinal/epidemiología , Herniorrafia/métodos , Laparoscopía/métodos , Femenino , Hernia Inguinal/cirugía , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estados Unidos/epidemiología
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