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1.
Plant Physiol ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38606947

RESUMEN

Natural variation in trichome pattern (amount and distribution) is prominent among populations of many angiosperms. However, the degree of parallelism in the genetic mechanisms underlying this diversity and its environmental drivers in different species remain unclear. To address these questions, we analyzed the genomic and environmental bases of leaf trichome pattern diversity in Cardamine hirsuta, a relative of Arabidopsis (Arabidopsis thaliana). We characterized 123 wild accessions for their genomic diversity, leaf trichome patterns at different temperatures, and environmental adjustments. Nucleotide diversities and biogeographical distribution models identified two major genetic lineages with distinct demographic and adaptive histories. Additionally, C. hirsuta showed substantial variation in trichome pattern and plasticity to temperature. Trichome amount in C. hirsuta correlated positively with spring precipitation but negatively with temperature, which is opposite to climatic patterns in A. thaliana. Contrastingly, genetic analysis of C. hirsuta glabrous accessions indicated that, like for A. thaliana, glabrousness is caused by null mutations in ChGLABRA1 (ChGL1). Phenotypic genome-wide association studies (GWAS) further identified a ChGL1 haplogroup associated with low trichome density and ChGL1 expression. Therefore, a ChGL1 series of null and partial loss-of-function alleles accounts for the parallel evolution of leaf trichome pattern in C. hirsuta and A. thaliana. Finally, GWAS also detected other candidate genes (e.g. ChETC3, ChCLE17) that might affect trichome pattern. Accordingly, the evolution of this trait in C. hirsuta and A. thaliana shows partially conserved genetic mechanisms but is likely involved in adaptation to different environments.

2.
Photosynth Res ; 161(1-2): 93-103, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38224422

RESUMEN

C-phycocyanin (C-PC) is the main component of water-soluble light-harvesting complexes (phycobilisomes, PBS) of cyanobacteria. PBS are involved in the absorption of quantum energy and the transfer of electronic excitation energy to the photosystems. A specific environment of C-PC chromophoric groups is provided by the protein matrix structure including protein-protein contacts between different subunits. Registration of C-PC spectral characteristics and the fluorescence anisotropy decay have revealed a significant pH influence on the chromophore microenvironment: at pH 5.0, a chromophore is more significantly interacts with the solvent, whereas at pH 9.0 the chromophore microenvironment becomes more viscous. Conformations of chromophores and the C-PC protein matrix have been studied by Raman and infrared spectroscopy. A decrease in the medium pH results in changes in the secondary structure either the C-PC apoproteins and chromophores, the last one adopts a more folded conformation.


Asunto(s)
Proteínas Bacterianas , Complejos de Proteína Captadores de Luz , Ficocianina , Spirulina , Ficocianina/química , Concentración de Iones de Hidrógeno , Polarización de Fluorescencia , Espectrometría Raman , Espectrofotometría Infrarroja , Estructura Secundaria de Proteína , Complejos de Proteína Captadores de Luz/química , Pliegue de Proteína , Spirulina/enzimología , Proteínas Bacterianas/química
3.
Am J Emerg Med ; 78: 102-111, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38244243

RESUMEN

INTRODUCTION: The widespread incorporation of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest requires the delivery of effective and high-quality chest compressions prior to the initiation of ECPR. The aim of this study was to evaluate and compare the effectiveness of mechanical and manual chest compressions until the initiation of ECPR. METHODS: This study was a secondary analysis of the Japanese retrospective multicenter registry "Study of Advanced Life Support for Ventricular Fibrillation by Extracorporeal Circulation II (SAVE-J II)". Patients were divided into two groups, one receiving mechanical chest compressions and the other receiving manual chest compressions. The primary outcome measure was mortality at hospital discharge, while the secondary outcome was the cerebral performance category (CPC) score at discharge. RESULTS: Of the 2157 patients enrolled in the SAVE-J II trial, 453 patients (329 in the manual compression group and 124 in the mechanical compression group) were included in the final analysis. Univariate analysis showed a significantly higher mortality rate at hospital discharge in the mechanical compression group compared to the manual compression group (odds ratio [95% CI] = 2.32 [1.34-4.02], p = 0.0026). Multivariate analysis showed that mechanical chest compressions were an independent factor associated with increased mortality at hospital discharge (adjusted odds ratio [95% CI] = 2.00 [1.11-3.58], p = 0.02). There was no statistically significant difference in CPC between the two groups. CONCLUSION: For patients with out-of-hospital cardiopulmonary arrest who require ECPR, extreme caution should be used when performing mechanical chest compressions.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Humanos , Masaje Cardíaco , Paro Cardíaco Extrahospitalario/terapia , Alta del Paciente , Fibrilación Ventricular/terapia , Estudios Retrospectivos
4.
Neurosurg Rev ; 47(1): 176, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38644441

RESUMEN

The use of endoscopic third ventriculostomy (ETV) for treatment of pediatric hydrocephalus has higher failure rates in younger patients. Here we investigate the impact of select perioperative variables, specifically gestational age, chronological age, birth weight, and surgical weight, on ETV failure rates. A retrospective review was performed on patients treated with ETV - with or without choroid plexus cauterization (CPC) - from 2010 to 2021 at a large academic center. Analyses included Cox regression for independent predictors and Kaplan-Meier survival curves for time to-event outcomes. In total, 47 patients were treated with ETV; of these, 31 received adjunctive CPC. Overall, 66% of the cohort experienced ETV failure with a median failure of 36 days postoperatively. Patients aged < 6 months at time of surgery experienced 80% failure rate, and those > 6 months at time of surgery experienced a 41% failure rate. Univariate Cox regression analysis showed weight at the time of ETV surgery was significantly inversely associated with ETV failure with a hazard ratio of 0.92 (95% CI 0.82, 0.99). Multivariate analysis redemonstrated the inverse association of weight at time of surgery with ETV failure with hazard ratio of 0.76 (95% CI 0.60, 0.92), and sensitivity analysis showed < 4.9 kg as the optimal cutoff predicting ETV/CPC failure. Neither chronologic age nor gestational age were found to be significantly associated with ETV failure.In this study, younger patients experienced higher ETV failure rates, but multivariate regression found that weight was a more robust predictor of ETV failure than chronologic age or gestational age, with an optimal cutoff of 4.9 kg in our small cohort. Given the limited sample size, further study is needed to elucidate the independent role of weight as a peri-operative variable in determining ETV candidacy in young infants. Previous presentations: Poster Presentation, Congress of Neurological Surgeons.


Asunto(s)
Hidrocefalia , Tercer Ventrículo , Ventriculostomía , Humanos , Hidrocefalia/cirugía , Femenino , Ventriculostomía/métodos , Masculino , Lactante , Tercer Ventrículo/cirugía , Estudios Retrospectivos , Preescolar , Niño , Insuficiencia del Tratamiento , Recién Nacido , Neuroendoscopía/métodos , Edad Gestacional , Plexo Coroideo/cirugía
5.
Molecules ; 29(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38930940

RESUMEN

Ammi majus L. (Apiaceae) is a medicinal plant with a well-documented history in phytotherapy. The aim of the present work was to isolate isopimpinellin (5,8-methoxypsoralen; IsoP) from the fruit of this plant and evaluate its biological activity against selected tumor cell lines. The methanol extract obtained with the use of an accelerated solvent extraction (ASE) method was the most suitable for the quantitative analysis of coumarins in the A. majus fruit matrix. The coumarin content was estimated by RP-HPLC/DAD, and the amount of IsoP was found to be 404.14 mg/100 g dry wt., constituting 24.56% of the total coumarin fraction (1.65 g/100 g). This, along with the presence of xanthotoxin (368.04 mg/100 g, 22.36%) and bergapten (253.05 mg/100 g, 15.38%), confirmed A. majus fruits as an excellent source of these compounds. IsoP was isolated (99.8% purity) by combined liquid chromatography/centrifugal partition chromatography (LC/CPC) and tested for the first time on its antiproliferative activity against human colorectal adenocarcinoma (HT29, SW620), osteosarcoma (Saos-2, HOS), and multiple myeloma (RPMI8226, U266) cell lines. MTT assay results (96 h incubation) demonstrated a dose- and cell line-dependent decrease in cell proliferation/viability, with the strongest effect of IsoP against the Saos-2 cell line (IC50; 42.59 µM), medium effect against U266, HT-29, and RPMI8226 (IC50 = 84.14, 95.53, and 105.0 µM, respectively), and very weak activity against invasive HOS (IC50; 321.6 µM) and SW620 (IC50; 711.30 µM) cells, as well as normal human skin fibroblasts (HSFs), with IC50; 410.7 µM. The mechanistic study on the Saos-2 cell line showed that IsoP was able to reduce DNA synthesis and trigger apoptosis via caspase-3 activation. In general, IsoP was found to have more potency towards cancerous cells (except for HOS and SW620) than against healthy cells. The Selective Index (SI) was determined, underlining the higher selectivity of IsoP towards cancer cells compared to healthy cells (SI = 9.62 against Saos-2). All these results suggest that IsoP might be a promising molecule in the chemo-prevention and treatment of primary osteosarcoma.


Asunto(s)
Ammi , Frutas , Furocumarinas , Extractos Vegetales , Humanos , Frutas/química , Línea Celular Tumoral , Furocumarinas/farmacología , Furocumarinas/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Ammi/química , Proliferación Celular/efectos de los fármacos , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Supervivencia Celular/efectos de los fármacos
6.
J Environ Sci (China) ; 141: 194-204, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38408820

RESUMEN

Effective density (ρeff) is one of the most important physical properties of atmospheric particles, providing important references in exploring the emissions and aging processes of fresh particles. In this study, a combined system of differential mobility analyzer, centrifugal particle mass analyzer, and condensation particle counter was used to periodically measure the ρeff of atmospheric particles in Shenzhen from Oct. 2021 to Jan. 2022. Results showed that the ρeff of particles with various size presented a bimodal distribution, which could be divided into main density (ρm, main peak, corresponding to relatively dense particles after aging) and sub density (ρs, sub peak, corresponding to fresh particles). The occurrence frequencies of ρs of particles with diameters of 50 and 80 nm were less than 20%, but were as high as about 40% of that with diameters from 120 to 350 nm. The ρm showed increasing trend with the size of particles, while ρs decreased as the increasing of the size of particles. The ρeff on pollution day varied significantly with chemical compositions. The increasing of the proportion of sulfate could promote the increasing of ρeff, while black carbon and organic matter caused opposite effects, which may be related to various factors, including the difference of the material density and morphology of various chemical components. The ρeff of 50, 80 and 120 nm particles decreased considerably during the new particle formation event, indicating that organic condensation was an important contributor to new particle growth.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Tamaño de la Partícula , Aerosoles/análisis , Atmósfera , China , Monitoreo del Ambiente/métodos
7.
EMBO Rep ; 22(11): e52061, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34423893

RESUMEN

H2A.Z is a H2A-type histone variant essential for many aspects of cell biology, ranging from gene expression to genome stability. From deuterostomes, H2A.Z evolved into two paralogues, H2A.Z.1 and H2A.Z.2, that differ by only three amino acids and are encoded by different genes (H2AFZ and H2AFV, respectively). Despite the importance of this histone variant in development and cellular homeostasis, very little is known about the individual functions of each paralogue in mammals. Here, we have investigated the distinct roles of the two paralogues in cell cycle regulation and unveiled non-redundant functions for H2A.Z.1 and H2A.Z.2 in cell division. Our findings show that H2A.Z.1 regulates the expression of cell cycle genes such as Myc and Ki-67 and its depletion leads to a G1 arrest and cellular senescence. On the contrary, H2A.Z.2, in a transcription-independent manner, is essential for centromere integrity and sister chromatid cohesion regulation, thus playing a key role in chromosome segregation.


Asunto(s)
Segregación Cromosómica , Histonas , Animales , Centrómero/metabolismo , Inestabilidad Genómica , Histonas/genética , Histonas/metabolismo
8.
Proc Natl Acad Sci U S A ; 117(20): 10935-10945, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32355000

RESUMEN

The circadian clock in eukaryotes controls transcriptional and posttranscriptional events, including regulation of the levels and phosphorylation state of translation factors. However, the mechanisms underlying clock control of translation initiation, and the impact of this potential regulation on rhythmic protein synthesis, were not known. We show that inhibitory phosphorylation of eIF2α (P-eIF2α), a conserved translation initiation factor, is clock controlled in Neurospora crassa, peaking during the subjective day. Cycling P-eIF2α levels required rhythmic activation of the eIF2α kinase CPC-3 (the homolog of yeast and mammalian GCN2), and rhythmic activation of CPC-3 was abolished under conditions in which the levels of charged tRNAs were altered. Clock-controlled accumulation of P-eIF2α led to reduced translation during the day in vitro and was necessary for the rhythmic synthesis of select proteins in vivo. Finally, loss of rhythmic P-eIF2α levels led to reduced linear growth rates, supporting the idea that partitioning translation to specific times of day provides a growth advantage to the organism. Together, these results reveal a fundamental mechanism by which the clock regulates rhythmic protein production, and provide key insights into how rhythmic translation, cellular energy, stress, and nutrient metabolism are linked through the levels of charged versus uncharged tRNAs.


Asunto(s)
Relojes Circadianos/fisiología , Factor 2 Eucariótico de Iniciación/metabolismo , Procesamiento Proteico-Postraduccional/fisiología , Animales , Ritmo Circadiano , Factor 2 Eucariótico de Iniciación/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Neurospora crassa/crecimiento & desarrollo , Neurospora crassa/metabolismo , Fosforilación , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , eIF-2 Quinasa/metabolismo
9.
BMC Emerg Med ; 23(1): 3, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635636

RESUMEN

BACKGROUND: The introduction of chest pain centers (CPC) in China has achieved great success in shortening the duration of nursing operations to significantly improve the treatment and outcomes of patients with ST-segment elevation myocardial infarction (STEMI). The nursing handover period is still considered the high incidence period of adverse events because of the distractibility of nurses' attention, potential interruption, and unclear responsibilities. Under the CPC mechanism, the nursing efficiency and patients' outcome, whether affected by the nursing handover, is still a knowledge gap in research. This is also the aim of this study. METHODS: A retrospective study was conducted with data from STEMI patients from a tertiary hospital in the north of Sichuan Province from January 2018 to December 2019 through the Chinese CPC database. Patients are divided into handover and non-handover groups according to the time they presented in the Emergency Department. D2FMC, FMC2FE, FMC2BS, FMC2CBR, FMC2FAD, and D2W were selected to measure nursing efficiency. The occurrence of major adverse cardiovascular events, the highest troponin values within 72 h of hospitalization, and the length of hospitalization were selected to measure the patient outcomes. Continuous variables are summarized as mean ± SD, and t-tests of the data were performed. P-values < 0.05 (two-tailed) were considered statistically significant. RESULTS: A total of 231 cases were enrolled, of which 40 patients (17.3%) were divided into the handover period group, and 191 (82.6%) belonged to the non-handover period group. The results showed that the handover period group took significantly longer on items FMC2BS (P < 0.001) and FMC2FAD (P < 0.001). Still, there were no significant differences in D2FMC and FMC2FE, and others varied too little to be clinically meaningful, as well as the outcomes of patients. CONCLUSION: This study confirms that nursing handover impacts the nursing efficiency of STEMI patients, especially in FMC2BS and FMC2FAD. Hospitals should also reform the nursing handover rules after the construction of CPC and enhance the triage training of nurses to assure nursing efficiency so that CPC can play a better role.


Asunto(s)
Pase de Guardia , Infarto del Miocardio con Elevación del ST , Humanos , Estudios Retrospectivos , Clínicas de Dolor , Servicio de Urgencia en Hospital , Dolor en el Pecho
10.
Molecules ; 28(4)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36838916

RESUMEN

Pure methoxyfuranocoumarins were isolated from a crude petroleum ether extract (CPE; Soxleth extraction efficiency 12.28%) from fruits of Peucedanum tauricum MB. (Apiaceae) by counter-current chromatography in a hydrostatic equilibrium system (centrifugal partition chromatography-CPC). The optimized biphasic solvent system composed of n-heptane-ethyl acetate-methanol-water (5:2:5:2; v/v/v/v) in the ascending mode of elution was used (3 mL/min, 1600 rpm). In the single run, peucedanin (P), 8-methoxypeucedanin (8MP), and bergapten (5MOP) were obtained as pure as 95.6%, 98.1%, and c.a. 100%, respectively. The carefully optimized and developed CPC was effectively transferred from the analytical to the semi-preparative scale (where 20 mg and 150 mg of CPE were loaded, respectively). Identification and quantitative analysis of methoxyfuranocoumarins was carried out in the plant material, in the CPE, and in individual CPC fractions by use of validated high-performance liquid chromatography with diode array detection and mass spectrometry (HPLC-DAD-ESI-MS). For the separation steps, the extraction/isolation recovery was calculated. In this case, CPC proved to be an effective tool for the simultaneous isolation and separation of P, 8MP, and 5MOP from a multicomponent plant matrix, without additional pre-purification steps. The high purity of the obtained plant metabolites makes it possible to consider their use in pharmacological or biological studies.


Asunto(s)
Apiaceae , Furocumarinas , 5-Metoxipsoraleno , Extractos Vegetales/química , Cromatografía Liquida/métodos , Furocumarinas/análisis , Solventes/química
11.
Molecules ; 28(16)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37630413

RESUMEN

Irradiation can be used for the preservation of chickpea protein as it can destroy microorganisms, bacteria, virus, or insects that might be present. However, irradiation may provoke oxidative stress, and therefore modify the functionality and nutritional value of chickpea protein. In order to study the effects of irradiation on the physicochemical properties and digestion behaviour of chickpea protein, chickpea protein concentrate (CPC) was treated with electron beam irradiation (EBI) at doses of 5, 10, 15, and 20 kGy. After irradiation, protein solubility first increased at 10 kGy and 15 kGy, and then decreased at the higher dose of 20 kGy. This was supported by SDS-PAGE, where the intensity of major protein bands first increased and then decreased. Increased doses of EBI generally led to greater oxidative modification of proteins in CPC, indicated by reduced sulfhydryls and increased carbonyls. In addition, the protein structure was modified by EBI as shown by Fourier transform infrared spectroscopy analysis, where α-helix generally decreased, and ß-sheet increased. Although the protein digestibility was not significantly affected by EBI, the peptidomic analysis of the digests revealed significant differences among CPC irradiated with varying doses. A total of 337 peptides were identified from CPC irradiated with 0 kGy, 10 kGy, and 20 kGy, with 18 overlapping peptides and 60, 29, and 40 peptides specific to the groups of 0, 10, and 20 kGy respectively. Theoretical calculation showed that the distribution of peptide length, hydrophobicity, net charge, and C-terminal residues were affected by irradiation. The 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity showed a marginal decrease with an increasing dose of irradiation. In conclusion, EBI led to oxidative modification and structural changes in chickpea protein, which subsequently affected the physicochemical properties of peptides obtained from in-vitro digestion of CPC, despite similar digestibility.


Asunto(s)
Cicer , Electrones , Electroforesis en Gel de Poliacrilamida , Valor Nutritivo , Estrés Oxidativo
12.
J Lipid Res ; 63(6): 100208, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35436499

RESUMEN

The lipid envelope of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an essential component of the virus; however, its molecular composition is undetermined. Addressing this knowledge gap could support the design of antiviral agents as well as further our understanding of viral-host protein interactions, infectivity, pathogenicity, and innate immune system clearance. Lipidomics revealed that the virus envelope comprised mainly phospholipids (PLs), with some cholesterol and sphingolipids, and with cholesterol/phospholipid ratio similar to lysosomes. Unlike cellular membranes, procoagulant amino-PLs were present on the external side of the viral envelope at levels exceeding those on activated platelets. Accordingly, virions directly promoted blood coagulation. To investigate whether these differences could enable selective targeting of the viral envelope in vivo, we tested whether oral rinses containing lipid-disrupting chemicals could reduce infectivity. Products containing PL-disrupting surfactants (such as cetylpyridinium chloride) met European virucidal standards in vitro; however, components that altered the critical micelle concentration reduced efficacy, and products containing essential oils, povidone-iodine, or chlorhexidine were ineffective. This result was recapitulated in vivo, where a 30-s oral rinse with cetylpyridinium chloride mouthwash eliminated live virus in the oral cavity of patients with coronavirus disease 19 for at least 1 h, whereas povidone-iodine and saline mouthwashes were ineffective. We conclude that the SARS-CoV-2 lipid envelope i) is distinct from the host plasma membrane, which may enable design of selective antiviral approaches; ii) contains exposed phosphatidylethanolamine and phosphatidylserine, which may influence thrombosis, pathogenicity, and inflammation; and iii) can be selectively targeted in vivo by specific oral rinses.


Asunto(s)
COVID-19 , Antisépticos Bucales , Antivirales , Cetilpiridinio , Humanos , Lípidos , Antisépticos Bucales/farmacología , Povidona Yodada , ARN Viral , SARS-CoV-2
13.
BMC Plant Biol ; 22(1): 506, 2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36309643

RESUMEN

BACKGROUND: CCCH-type zinc finger proteins play important roles in plant development and biotic/abiotic stress responses. Wintersweet (Chimonanthus praecox) is a popular ornamental plant with strong resistance to various stresses, which is a good material for exploring gene resource for stress response. In this study, we isolated a CCCH type zinc finger protein gene CpC3H3 (MZ964860) from flower of wintersweet and performed functional analysis with a purpose of identifying gene resource for floral transition and stress tolerance. RESULTS: CpC3H3 was predicted a CCCH type zinc finger protein gene encoding a protein containing 446 amino acids with five conserved C-X8-C-X5-C-X3-H motifs. CpC3H3 was localized in the cell membrane but with a nuclear export signal at the N-terminal. Transcripts of CpC3H3 were significantly accumulated in flower buds at floral meristem formation stage, and were induced by polyethylene glycol. Overexpression of CpC3H3 promoted flowering, and enhanced drought tolerance in transgenic A. thaliana. CpC3H3 overexpression affects the expression level of genes involved in flower inducement and stress responses. Further comparative studies on physiological indices showed the contents of proline and soluble sugar, activity of peroxidase and the rates of electrolyte leakage were significantly increased and the content of malondialdehyde and osmotic potential was significantly reduced in transgenic A. thaliana under PEG stress. CONCLUSION: Overall, CpC3H3 plays a role in flowering inducement and drought tolerance in transgenic A. thaliana. The CpC3H3 gene has the potential to be used to promote flowering and enhance drought tolerance in plants.


Asunto(s)
Arabidopsis , Arabidopsis/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Dedos de Zinc/genética , Estrés Fisiológico/genética
14.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1675-1685, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34902059

RESUMEN

PURPOSE: To examine systematically how prechiasmal, chiasmal, and postchiasmal lesions along the visual pathway affect the respective pupillary responses to specific local monochromatic stimuli. METHODS: Chromatic pupil campimetry (CPC) was performed in three patient groups (10 subjects with status after anterior ischemic optic neuropathy, 6 with chiasmal lesions, and 12 with optic tract or occipital lobe lesions (tumor, ischemia)) using red, low-intensity red, and blue local stimuli within the central 30° visual field. Affected areas - as determined by visual field defects revealed using conventional static perimetry - were compared with non-affected areas. Outcome parameters were the relative maximal constriction amplitude (relMCA) and the latency to constriction onset of the pupillary responses. RESULTS: A statistically significant relMCA reduction was observed in the affected areas of postchiasmal lesions with red (p = 0.004) and low-intensity red stimulation (p = 0.001). RelMCA reduction in the affected areas seemed more pronounced for low-intensity red stimulation (46.5% mean reduction compared to non-affected areas; 36% for red stimulation), however statistically not significant. In prechiasmal lesions, a statistically significant latency prolongation could be demonstrated in the affected areas with low-intensity red stimulation (p = 0.015). CONCLUSION: Our results indicate that the choice of stimulus characteristics is relevant in detecting defects in the pupillary pathway of impairment along the visual pathway, favoring red stimuli of low intensity over blue stimuli. Such knowledge opens the door for further fundamental research in pupillary pathways and is important for future clinical application of pupillography in neuro-ophthalmologic patients.


Asunto(s)
Trastornos de la Pupila , Vías Visuales , Humanos , Estimulación Luminosa , Pupila/fisiología , Trastornos de la Pupila/diagnóstico , Reflejo Pupilar/fisiología , Pruebas del Campo Visual , Campos Visuales
15.
BMC Musculoskelet Disord ; 23(1): 170, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193563

RESUMEN

BACKGROUND: Giant cell tumor of bone (GCTB) is an intermediate tumor commonly arising from the epiphysis of the distal femur and proximal tibia. Standard GCTB treatment is joint-preserving surgery performed using thorough curettage and the filling of the cavity with allo-, auto-, polymethyl methacrylate (PMMA), or synthetic bone graft. Calcium phosphate cement (CPC) is an artificial bone substitute, which has the benefit of being able to adjust defects, consequently inducing immediate mechanical strength, and promoting biological healing. Secondary osteoarthritis may occur following GCTB treatment and may need additional surgery if severe. However, details regarding surgery for secondary osteoarthritis have not been fully elucidated. There are no reports on the use of total knee arthroplasty (TKA) for the treatment of secondary osteoarthritis following CPC packing. The insertion of an alignment rod is a standard procedure in TKA; however, it was difficult to perform in this case due to CPC. Therefore, we used a computed tomography (CT)-free navigation system to assist the distal femur cut. This study presents a knee joint secondary osteoarthritis case following CPC packing for GCTB curettage that was treated with standard TKA. CASE PRESENTATION: A 67-year-old Japanese woman, who was previously diagnosed with left distal femur GCTB and was treated by curettage and CPC packing 7 years ago, complained of severe knee pain. Left knee joint plain radiography revealed Kellgren and Lawrence (K-L) grade 4 osteoarthritis without evidence of tumor recurrence. Therefore, she was scheduled for TKA. There are no reports on the cutting of a femoral condyle surface with massive CPC with accurate alignment. Because it is difficult to insert the alignment rod intramedullary and cut the femoral condyle with CPC, we planned CT-free navigation-guided surgery for accurate bone cutting using an oscillating tip saw system to prevent CPC cracks. We performed standard TKA without complications, as planned. Postoperative X-ray showed normal alignment. Knee Society Knee Score (KSKS) and Knee Society Function Score (KSFS) ameliorated from 27 and 29 to 64 and 68, respectively The patient can walk without a cane postoperatively. CONCLUSION: There was no report about the surface TKA guided by CT-free navigation after primary GCT surgery with CPC. We believe that this case report will help in planning salvage surgery for secondary osteoarthritis after CPC packing.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Tumor Óseo de Células Gigantes , Osteoartritis de la Rodilla , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Fosfatos de Calcio/uso terapéutico , Femenino , Fémur/diagnóstico por imagen , Fémur/cirugía , Tumor Óseo de Células Gigantes/cirugía , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/patología , Osteoartritis de la Rodilla/cirugía , Estudios Retrospectivos , Tibia/diagnóstico por imagen , Tibia/patología , Tibia/cirugía , Tomografía Computarizada por Rayos X
16.
Chem Biodivers ; 19(3): e202100827, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34964548

RESUMEN

Carduus nutans L. (Compositae) has been extensively used for medicinal purposes. As other representatives of the genus it is implemented in the treatment of liver disorders and used as diuretic and digestive agent. Previous studies have determined the predominant classes of secondary metabolites in Carduus species. Among the major representatives of their extracts flavonoids, phenolic acids, coumarins, sterols and terpenes were identified. The antiradical capacity of three extracts assessed in the DPPH test revealed the highest radical scavenging properties of methanol extract (the EC50 618±10.03 µg/mL) and based on these results it was selected for phenolic content determination. (TPC=61.49 mg/g). To understand better the induced pharmacological effects of the plant the aim of the study was to determine the composition of the methanol extract from the inflorescences of C. nutans and to study their phenolic composition. In order to determine the composition in a more efficient way, the crude extract was fractionated and subjected to hydrolyses. As a result more than twenty phenolic acids and flavonoids were identified in the extract and fractions by HPLC-DAD and/or HPLC-ESI-TOF-MS. The total extract was later subjected to fractionation by centrifugal partition chromatography using the Arizona system composed of hexane/ethyl acetate/methanol/water (0.7 : 4 : 0.8 : 4 v/v/v/v) to produce fractions enriched in flavonoids that are of high pharmacological significance.


Asunto(s)
Carduus , Antioxidantes/química , Flavonoides/química , Inflorescencia/química , Fenoles/análisis , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología
17.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36142236

RESUMEN

Gastric cancer (GC) has high incidence rates and constitutes a common cause of cancer mortality. Despite advances in treatment, GC remains a challenge in cancer therapy which is why novel treatment strategies are needed. The interest in natural compounds has increased significantly in recent years because of their numerous biological activities, including anti-cancer action. The isolation of the bioactive compounds from Coptis chinensis Franch was carried out with the Centrifugal Partition Chromatography (CPC) technique, using a biphasic solvent system composed of chloroform (CHCl3)-methanol (MeOH)-water (H2O) (4:3:3, v/v) with an addition of hydrochloric acid and trietylamine. The identity of the isolated alkaloids was confirmed using a high resolution HPLC-MS chromatograph. The phytochemical constituents of Coptis chinensis such as berberine, jatrorrhizine, palmatine and coptisine significantly inhibited the viability and growth of gastric cancer cell lines ACC-201 and NCI-N87 in a dose-dependent manner, with coptisine showing the highest efficacy as revealed using MTT and BrdU assays, respectively. Flow cytometry analysis confirmed the coptisine-induced population of gastric cancer cells in sub-G1 phase and apoptosis. The combination of coptisine with cisplatin at the fixed-ratio of 1:1 exerted synergistic and additive interactions in ACC-201 and NCI-N87, respectively, as determined by means of isobolographic analysis. In in vivo assay, coptisine was safe for developing zebrafish at the dose equivalent to the highest dose active in vitro, but higher doses (greater than 10 times) caused morphological abnormalities in larvae. Our findings provide a theoretical foundation to further studies on more detailed mechanisms of the bioactive compounds from Coptis chinensis Franch anti-cancer action that inhibit GC cell survival in in vitro settings.


Asunto(s)
Alcaloides , Alcaloides de Berberina , Berberina , Coptis , Medicamentos Herbarios Chinos , Neoplasias Gástricas , Alcaloides/análisis , Alcaloides/farmacología , Animales , Berberina/análogos & derivados , Berberina/farmacología , Alcaloides de Berberina/farmacología , Bromodesoxiuridina , Cloroformo , Cisplatino , Coptis/química , Coptis chinensis , Medicamentos Herbarios Chinos/química , Ácido Clorhídrico , Isoquinolinas , Metanol , Solventes , Neoplasias Gástricas/tratamiento farmacológico , Agua , Pez Cebra
18.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36430714

RESUMEN

Diabetes is a long-term metabolic disorder characterized by persistently elevated blood sugar levels. Chronic hyperglycemia enhances glucose-protein interactions, leading to the formation of advanced glycation end products (AGEs), which form irreversible cross-links with a wide variety of macromolecules, and accumulate rapidly in the body tissues. Thus, the objective of this study was to assess the therapeutic properties of C-phycocyanin (C-PC) obtained from Plectonema species against oxidative stress, glycation, and type 2 diabetes mellitus (T2DM) in a streptozotocin (STZ)-induced diabetic Wistar rat. Forty-five days of C-PC administration decreased levels of triglycerides (TGs), blood glucose, glycosylated hemoglobin, (HbA1c), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), liver and kidney function indices, and raised body weight in diabetic rats. C-PC suppressed biochemical glycation markers, as well as serum carboxymethyllysine (CML) and fluorescent AGEs. Additionally, C-PC maintained the redox state by lowering lipid peroxidation and protein-bound carbonyl content (CC), enhancing the activity of high-density lipoprotein cholesterol (HDL-C) and renal antioxidant enzymes, and preserving retinal and renal histopathological characteristics. Thus, we infer that C-PC possesses antidiabetic and antiglycation effects in diabetic rats. C-PC may also act as an antidiabetic and antiglycation agent in vivo that may reduce the risk of secondary diabetic complications.


Asunto(s)
Productos Biológicos , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Hiperglucemia , Ratas , Animales , Diabetes Mellitus Experimental/metabolismo , Estreptozocina , Ficocianina/farmacología , Ficocianina/uso terapéutico , Productos Biológicos/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Ratas Wistar , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Hiperglucemia/tratamiento farmacológico , HDL-Colesterol
19.
Int Ophthalmol ; 42(8): 2363-2369, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35113312

RESUMEN

PURPOSE: The aim of this study is to address the safety and effectiveness of a second continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) treatment by comparing its outcome against a first CW-TSCPC treatment in the same patients with refractory glaucoma. METHODS: Twenty-one eyes with either primary or secondary glaucoma received a second CW-TSCPC laser session ≥ 3 months after the first treatment. Intraocular pressure (IOP), best-corrected visual acuity (BCVA), and number of topical or oral ophthalmic pressure-reducing medications were registered at every time point up to the last follow-up at 3 months. A complete slit-lamp examination was conducted to record for complications or other abnormal ocular findings. Success was defined as IOP between 6 and 21 mmHg and > 20% reduction in IOP with or without anti-glaucoma medications. RESULTS: At 3 months follow-up of the first CW-TSCPC treatment, a 24.8% decrease in IOP was observed, whereas a 45.6% IOP decrease was observed 3 months post the second CW-TSCPC treatment. Visual acuity did not decrease, and no major complications were observed post either treatment within the follow-up period. Time to failure was 79.5 ± 24.6 and 77.1 ± 29.4, respectively (P = 0.955). No serious complications were observed. CONCLUSION: A second CW-TSCPC treatment proved to be a safe and effective treatment option when the first CW-TSCPC treatment was insufficient in maintaining the desired IOP level for a prolonged time (mean time between both sessions 6.4 ± 8.0 months).


Asunto(s)
Glaucoma , Presión Intraocular , Cuerpo Ciliar/cirugía , Estudios de Seguimiento , Glaucoma/cirugía , Humanos , Coagulación con Láser , Estudios Retrospectivos , Esclerótica/cirugía , Tonometría Ocular , Resultado del Tratamiento
20.
J Cell Sci ; 132(21)2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31601613

RESUMEN

Timely and precise control of Aurora B kinase, the chromosomal passenger complex (CPC) catalytic subunit, is essential for accurate chromosome segregation and cytokinesis. Post-translational modifications of CPC subunits are directly involved in controlling Aurora B activity. Here, we identified a highly conserved acidic STD-rich motif of INCENP that is phosphorylated during mitosis in vivo and by Plk1 in vitro and is involved in controlling Aurora B activity. By using an INCENP conditional-knockout cell line, we show that impairing the phosphorylation status of this region disrupts chromosome congression and induces cytokinesis failure. In contrast, mimicking constitutive phosphorylation not only rescues cytokinesis but also induces ectopic furrows and contractile ring formation in a Plk1- and ROCK1-dependent manner independent of cell cycle and microtubule status. Our experiments identify the phospho-regulation of the INCENP STD motif as a novel mechanism that is key for chromosome alignment and cytokinesis.This article has an associated First Person interview with the first author of the paper.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/fisiología , Microtúbulos/metabolismo , Mutación/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Cromosomas/metabolismo , Citocinesis/fisiología , Humanos , Mitosis/fisiología , Quinasas Asociadas a rho/metabolismo , Quinasa Tipo Polo 1
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