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1.
Nature ; 598(7879): 144-150, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33184512

RESUMEN

Cortical neurons exhibit extreme diversity in gene expression as well as in morphological and electrophysiological properties1,2. Most existing neural taxonomies are based on either transcriptomic3,4 or morpho-electric5,6 criteria, as it has been technically challenging to study both aspects of neuronal diversity in the same set of cells7. Here we used Patch-seq8 to combine patch-clamp recording, biocytin staining, and single-cell RNA sequencing of more than 1,300 neurons in adult mouse primary motor cortex, providing a morpho-electric annotation of almost all transcriptomically defined neural cell types. We found that, although broad families of transcriptomic types (those expressing Vip, Pvalb, Sst and so on) had distinct and essentially non-overlapping morpho-electric phenotypes, individual transcriptomic types within the same family were not well separated in the morpho-electric space. Instead, there was a continuum of variability in morphology and electrophysiology, with neighbouring transcriptomic cell types showing similar morpho-electric features, often without clear boundaries between them. Our results suggest that neuronal types in the neocortex do not always form discrete entities. Instead, neurons form a hierarchy that consists of distinct non-overlapping branches at the level of families, but can form continuous and correlated transcriptomic and morpho-electrical landscapes within families.


Asunto(s)
Perfilación de la Expresión Génica , Corteza Motora/citología , Neuronas/clasificación , Neuronas/metabolismo , Transcriptoma , Animales , Atlas como Asunto , Femenino , Neuronas GABAérgicas/citología , Neuronas GABAérgicas/metabolismo , Glutamatos/metabolismo , Lisina/análogos & derivados , Lisina/análisis , Masculino , Ratones , Corteza Motora/anatomía & histología , Neuronas/citología , Especificidad de Órganos , Técnicas de Placa-Clamp , Fenotipo , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Coloración y Etiquetado
2.
Opt Express ; 32(8): 13197-13207, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859296

RESUMEN

Silicon-based Micro Ring Resonators (MRR) are a powerful tool for the realization of label free optical biosensors. The sharp edge of a Fano resonance in a Silicon Nitride (Si3N4) platform can boost photonic sensing applications based on MRRs. In this work, we demonstrate enhanced Fano resonance features for a Si3N4 Micro Ring Resonator assisted by a Photonic Crystal Nanobeam (PhCN-MRR) operating in the TM-like mode at the O-band wavelengths. Our findings show that the fabricated PhCN-MRR results in increased asymmetric resonances for TM-like mode compared with TE-like mode operation in the C-band. As a result, a versatile and flexible design to realize Fano resonance with polarization dependent asymmetry in the C and O telecom bands is presented.

3.
Molecules ; 29(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38202822

RESUMEN

The two enantiomers of chiral phosphonate 4-phenyldinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepine 4-oxide, O=PPh(BINOL), were synthesized from the proper 1,1'-bi-2-naphtol (BINOL) enantiomer and characterized. The structure of the (S)-enantiomer was elucidated by means of single-crystal X-ray diffraction. The reaction with anhydrous ZnBr2 afforded complexes having the general formula [ZnBr2{O=PPh(BINOL)}2] that showed intense fluorescence centered in the near-UV region rationalized on the basis of TD-DFT calculations. The corresponding Mn(II) complexes with the general formula [MnX2{O=PPh(BINOL)}2] (X = Cl, Br) exhibited dual emission upon excitation with UV light, with the relative intensity of the bands dependent upon the choice of the halide. The highest energy transition is comparable with that of the Zn(II) complex, while the lowest energy emission falls in the red region of the spectrum and is characterized by lifetimes in the hundreds of microseconds range. Although the emission at lower energy can also be achieved by direct excitation of the metal center, the luminescence decay curves suggest that the band in the red range is possibly derived from BINOL-centered excited states populated by intersystem crossing.

4.
J Quant Spectrosc Radiat Transf ; 302: 108567, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36945203

RESUMEN

Objective: To conduct a proof-of-concept study of the detection of two synthetic models of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using polarimetric imaging. Approach: Two SARS-CoV-2 models were prepared as engineered lentiviruses pseudotyped with the G protein of the vesicular stomatitis virus, and with the characteristic Spike protein of SARS-CoV-2. Samples were prepared in two biofluids (saline solution and artificial saliva), in four concentrations, and deposited as 5-µL droplets on a supporting plate. The angles of maximal degree of linear polarization (DLP) of light diffusely scattered from dry residues were determined using Mueller polarimetry from87 samples at 405 nm and 514 nm. A polarimetric camera was used for imaging several samples under 380-420 nm illumination at angles similar to those of maximal DLP. Per-pixel image analysis included quantification and combination of polarization feature descriptors in 475 samples. Main results: The angles (from sample surface) of maximal DLP were 3° for 405 nm and 6° for 514 nm. Similar viral particles that differed only in the characteristic spike protein of the SARS-CoV-2, their corresponding negative controls, fluids, and the sample holder were discerned at 10-degree and 15-degree configurations. Significance: Polarimetric imaging in the visible spectrum may help improve fast, non-contact detection and identification of viral particles, and/or other microbes such as tuberculosis, in multiple dry fluid samples simultaneously, particularly when combined with other imaging modalities. Further analysis including realistic concentrations of real SARS-CoV-2 viral particles in relevant human fluids is required. Polarimetric imaging under visible light may contribute to a fast, cost-effective screening of SARS-CoV-2 and other pathogens when combined with other imaging modalities.

5.
Int J Mol Sci ; 24(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37628731

RESUMEN

Malaria is the most lethal parasitic disease worldwide; the severity of symptoms and mortality are higher in men than in women, exhibiting an evident sexual dimorphism in the immune response; therefore, the contribution of 17ß-estradiol and testosterone to this phenomenon has been studied. Both hormones differentially affect several aspects of innate and adaptive immunity. Dehydroepiandrosterone (DHEA) is the precursor of both hormones and is the sexual steroid in higher concentrations in humans, with immunomodulatory properties in different parasitic diseases; however, the involvement of DHEA in this sexual dimorphism has not been studied. In the case of malaria, the only information is that higher levels of DHEA are associated with reduced Plasmodium falciparum parasitemia. Therefore, this work aims to analyze the DHEA contribution to the sexual dimorphism of the immune response in malaria. We assessed the effect of modifying the concentration of DHEA on parasitemia, the number of immune cells in the spleen, cytokines, and antibody levels in plasma of CBA/Ca mice infected with Plasmodium berghei ANKA (P. berghei ANKA). DHEA differentially affected the immune response in males and females: it decreased IFN-γ, IL-2 and IL-4 concentrations only in females, whereas in gonadectomized males, it increased IgG2a and IgG3 antibodies. The results presented here show that DHEA modulates the immune response against Plasmodium differently in each sex, which helps to explain the sexual dimorphism present in malaria.


Asunto(s)
Citocinas , Plasmodium berghei , Masculino , Humanos , Ratones , Femenino , Animales , Ratones Endogámicos CBA , Parasitemia , Deshidroepiandrosterona
6.
Chemistry ; 28(72): e202202366, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36121738

RESUMEN

The last decade has seen an increasingly large number of studies reporting on the development of novel small organic conjugated systems for mitochondrial imaging exploiting optical signal transduction pathways. Mitochondria are known to play a critical role in a number of key biological processes, including cellular metabolism. Importantly, irregularities on their working function are nowadays understood to be intimately linked to a range of clinical conditions, highlighting the importance of targeting mitochondria for therapeutic benefits. In this work we carry out an in-depth evaluation on the progress to date in the field to pave the way for the realization of superior alternatives to those currently existing. The manuscript is structured by commonly used chemical scaffolds and comprehensively covers key aspects factored in design strategies such as synthetic approaches as well as photophysical and biological characterization, to foster collaborative work among organic and physical chemists as well as cell biologists.


Asunto(s)
Diagnóstico por Imagen , Mitocondrias , Mitocondrias/metabolismo , Transducción de Señal
7.
Neurodegener Dis ; 22(3-4): 151-158, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37231965

RESUMEN

INTRODUCTION: Cerebrospinal fluid (CSF) biomarker quantification provides physicians with a reliable diagnosis of Alzheimer's disease (AD). However, the relationship between their concentration and disease course has not been clearly elucidated. This work aimed to investigate the clinical and prognostic significance of Aß40 CSF levels. METHODS: A retrospective cohort of 76 patients diagnosed with AD using a decreased Aß42/Aß40 ratio was subclassified into hyposecretors (Aß40 <7,755 pg/mL), normosecretors (Aß40 7,755-16,715 pg/mL), and hypersecretors (Aß40 >16,715 pg/mL). Potential differences in AD phenotype, Montreal Cognitive Assessment (MoCA) scores, and Global Deterioration Scale (GDS) stages were assessed. Correlation tests for biomarker concentrations were also performed. RESULTS: Participants were classified as hyposecretors (n = 22, median Aß40 5,870.500 pg/mL, interquartile range [IQR] 1,431), normosecretors (n = 47, median Aß40 10,817 pg/mL, IQR 3,622), and hypersecretors (n = 7, 19,767 pg/mL, IQR 3,088). The distribution of positive phosphorylated Tau (p-Tau) varied significantly between subgroups and was more common in the normo- and hypersecretor categories (p = 0.003). Aß40 and p-Tau concentrations correlated positively (ρ = 0.605, p < 0.001). No significant differences were found among subgroups regarding age, initial MoCA score, initial GDS stage, progression to the dementia stage, or changes in the MoCA score. CONCLUSION: In this study, we found no significant differences in clinical symptoms or disease progression in AD patients according to their CSF Aß40 concentration. Aß40 was positively correlated with p-Tau and total Tau concentrations, supporting their potential interaction in AD pathophysiology.

8.
Mar Drugs ; 19(2)2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33572171

RESUMEN

Most of the shellfish fisheries of Mexico occur in the Gulf of California. In this region, known for its high primary productivity, blooms of diatoms and dinoflagellates are common, occurring mainly during upwelling events. Dinoflagellates that produce lipophilic toxins are present, where some outbreaks related to okadaic acid and dinophisystoxins have been recorded. From January 2015 to November 2017 samples of three species of wild bivalve mollusks were collected monthly in five sites in the southern region of Bahía de La Paz. Pooled tissue extracts were analyzed using LC-MS/MS to detect lipophilic toxins. Eighteen analogs of seven toxin groups, including cyclic imines were identified, fortunately individual toxins did not exceed regulatory levels and also the total toxin concentration for each bivalve species was lower than the maximum permitted level for human consumption. Interspecific differences in toxin number and concentration were observed in three species of bivalves even when the samples were collected at the same site. Okadaic acid was detected in low concentrations, while yessotoxins and gymnodimines had the highest concentrations in bivalve tissues. Although in low quantities, the presence of cyclic imines and other lipophilic toxins in bivalves from the southern Gulf of California was constant.


Asunto(s)
Bivalvos/metabolismo , Toxinas Marinas/análisis , Animales , Compuestos Heterocíclicos con 3 Anillos/análisis , Hidrocarburos Cíclicos/análisis , Iminas/análisis , Toxinas Marinas/química , Venenos de Moluscos , Ácido Ocadaico/análisis , Oxocinas/análisis , Solubilidad
9.
J Emerg Med ; 61(4): e77-e79, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34215471

RESUMEN

BACKGROUND: The presence of abrupt anisocoria in clinical examination usually leads to the performance of urgent neuroimaging studies to exclude intracranial hemorrhage, although unilateral mydriasis might be the result of other benign etiologies. CASE REPORT: In this work, we report an illustrative case of a patient presenting with sudden-onset anisocoria while receiving ipratropium bromide nebulization in the emergency department to treat acute asthma. No other abnormalities were found on neurological examination and the computed tomography scan was normal. As a muscarinic antagonist, ipratropium bromide can produce mydriasis if accidentally instilled on one eye, thus leading to the suspicion of pharmacologic mydriasis. The pupils became isocoric after the discontinuation of the drug. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: A careful neurological examination and the history of treatment with mydriatic drugs might avoid unnecessary tests and radiation exposure.


Asunto(s)
Asma , Midriasis , Anisocoria/inducido químicamente , Anisocoria/diagnóstico , Humanos , Ipratropio/efectos adversos , Midriasis/inducido químicamente , Tomografía Computarizada por Rayos X
10.
Chemistry ; 26(14): 3173-3180, 2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-32083355

RESUMEN

Development of novel bioimaging materials that exhibit organelle specific accumulation continues to be at the forefront of research interests and efforts. Among the various subcellular organelles, mitochondria, which are found in the cytoplasm of eukaryotic cells, are of particular interest in relation to their vital function. To date, most molecular probes that target mitochondria utilise delocalised lipophilic cations such as triphenylphosphonium and pyridinium. However, the use of such charged motifs is known to be detrimental to the working function of the mitochondrial transmembrane potential and there remains a strong case for development of neutral mitochondrial fluorescent probes. Herein, we demonstrate for the first time the exploitation of diketopyrrolopyrrole-based chemistries for the realisation of a neutral fluorescent probe that exhibits organelle specific accumulation within the mitochondria at the nanomolar level. The synthesised probe, which bears a neutral triphenylphosphine oxide moiety, exhibits a large Stokes shift and high fluorescence quantum yield in water, both highly sought-after properties in the development of bioimaging agents. In vitro studies reveal no interference with cell metabolism when tested for the human MCF7 breast cancer cell and nanomolar subcellular organelle colocalisation with commercially available mitochondrial staining agent Mitotracker Red. In light of its novelty, neutral structure and the preferential accumulation at nanomolar concentrations we anticipate this work to be of significant interest for the increasingly larger community devoted to the realisation of neutral mitochondrial selective systems and more widely to those engaged in the rational development of superior organic architectures in the biological field.


Asunto(s)
Colorantes Fluorescentes/química , Cetonas/química , Mitocondrias/metabolismo , Compuestos Organofosforados/química , Pirroles/química , Técnicas Biosensibles , Humanos , Luz , Células MCF-7 , Potencial de la Membrana Mitocondrial/fisiología , Estructura Molecular , Imagen Óptica , Compuestos Orgánicos/química , Relación Estructura-Actividad
11.
Phys Chem Chem Phys ; 22(43): 25315-25324, 2020 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-33140765

RESUMEN

The development of novel π-conjugated charge transfer mediators is at the forefront of current research efforts and interests. Among the plethora of building blocks, diketopyrrolopyrroles have been widely employed, associated to the ease of tailoring their optoelectronic properties by systematic peripheral substitutions. It is somehow of surprise to us that their six-member ring bis-lactam analogues, naphthyridines have been overlooked and reports are scarce and almost solely limited to their use in polymeric materials. Herein we report a comprehensive theoretical analysis of the charge transfer properties of 1,5-naphthyridine-based materials by means of a number of bespoke model systems, further able to quantitatively predict experimental mobility observations. Our results imply that thiophene substituted naphthyridine crystalline materials represent a promising class of organic π-conjugated systems with an experimentally observed ability to self-assemble in the solid state conforming to one dimensional stacking motifs. These highly sought-after charge propagation channels are characterised by large wavefunction overlap and thermal integrity and have as a result the potential to outperform currently exploited alternatives. We anticipate this work to be of interest to materials scientists and hope it will pave the way towards the realisation of novel charge transfer mediators exploiting naphthyridine chemistries.

12.
Phys Chem Chem Phys ; 22(43): 25156-25164, 2020 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-33124629

RESUMEN

Photoluminescence quantum yields denote a critical variable to characterise a fluorophore and its potential performance. Their determination, by means of methodologies employing reference standard materials, inevitably leads to large uncertainties. In response to this, herein we report for the first time an innovative and elegant methodology, whereby the use of neat solvent/reference material required by thermal lens approaches is eliminated by coupling it to photoluminescence spectroscopy, allowing for the discrimination between materials with similar photoluminescence quantum yields. To achieve this, both radiative and non-radiative transitions are simultaneously measured using a photoluminescence spectrometer coupled to a multiwavelength thermal lens spectroscopy setup in a mode-mismatched dual-beam configuration, respectively. The absorption factor independent ratio of the thermal lens and photoluminescence signals can then be used to determine the fluorescence quantum yield both accurately and precisely. We validated our reported method using rhodamine 6G and further applied it to three novel structurally related diketopyrrolopyrrole based materials, which, in contrast to results obtained by other methods, unveiled significant differences in their photoluminescence quantum yields.

13.
J Phys Chem A ; 123(14): 3185-3193, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30896170

RESUMEN

Small organic conjugated systems displaying one-dimensional stacking motifs in the solid state that facilitate charge propagation are highly desirable. Noncovalent interactions, although weak, can synergistically provide those supramolecular architectures with large binding energies and associated thermal integrity. Amongst the plethora of intermolecular interactions contributing toward the overall lattice energy and stability of the charge-propagation supramolecular architectures, H-bonding interactions are well-known to play a pivotal role. Despite their critical contribution, the positions of hydrogen atoms in X-ray crystallographic data are parameterized, which can lead to significant changes in the computed intermolecular interactions. Herein, we report for the first time an analysis of the role that the optimization of the H atoms in X-ray structures has in the computed intermolecular interactions energies in diketopyrrolopyrroles (DPPs). A large dataset comprising 94 dimer pairs from 19 different DPP-based systems, including three pigment analogues, was employed. In total, more than 1400 H-X chemical bonds were considered and optimized using the M06-2X density functional at the 6-311G(d) level. Intermolecular interactions were computed for the H-optimized geometries and compared to those from nonoptimized counterparts. We report that in 35 out of the 94 dimer pairs investigated (37%), the computed intermolecular interactions were at least 2.5 kJ mol-1 larger on progression to the H-optimized geometries. In turn, lower computed values were yielded upon H-optimization computed for 8 out of the 94 dimer pairs (8%), with one case exhibiting a difference greater than 2.5 kJ mol-1. In line with the negligible changes to electron density and wavefunction overlap, the computed changes on the transfer integrals for the hole and electron were always lower than 1 kJ mol-1. The observed changes to computed intermolecular interactions can play a critical role in determining the thermal integrity of the supramolecular structures and charge propagation channels, and thus in the absence of neutron diffraction data, H atoms should be optimized prior to computation. We envisage that the results herein will be of interest to the extensive scientific community devoted to the understanding of intermolecular interactions in organic conjugated systems and the realization of superior charge-transfer-mediating materials, and given the plethora of intermolecular interactions investigated, the results are not solely limited to DPP-based architectures.

14.
Gastroenterol Hepatol ; 42(9): 527-533, 2019 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31421857

RESUMEN

OBJECTIVES: To analyse the effect of a delay attributable to the healthcare system on a consecutive cohort of outpatients diagnosed with colorectal cancer in the healthcare area of Ourense (Spain). PATIENTS AND METHODS: We performed a retrospective cohort study that included patients diagnosed between 2009 and 2017. Delay attributable to the healthcare system was defined as the time between the first consultation with symptoms and the diagnostic confirmation. A logistic regression model was performed to evaluate the relationship between stage IV CRC and diagnostic delay. To analyse which variables were associated independently with overall mortality and mortality due to CRC we used a Cox regression model. RESULTS: 575 patients were included (men 64.5%, age 71.9 ± 11.5 years), with a delay attributable to the healthcare system of 115 ± 153 days. None of the variables analysed were associated with tumour stage at diagnosis. With a mean follow-up of 30.6 ± 21 months, 121 patients died (79.3% due to CRC). The variables independently associated with CRC-related mortality were metastatic CRC (HR 50.65, 95% CI 12.28-209), age (HR 1.04, 95% CI 1.02-1.05) and colonoscopy requested from the Primary Healthcare level (HR 0.55, 95% CI 0.36-0.88). CONCLUSIONS: Diagnostic delay attributable to the healthcare system is not related to the prognosis or stage of CRC. However, a direct referral to colonoscopy from the Primary Healthcare level reduces the risk of mortality in our patients.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/mortalidad , Diagnóstico Tardío/efectos adversos , Sector de Atención de Salud , Factores de Edad , Anciano , Colonoscopía/estadística & datos numéricos , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Tiempo
15.
Mediators Inflamm ; 2018: 5258797, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30515051

RESUMEN

Cerebral malaria (CM) is the major complication associated with death in malaria patients, and its pathogenesis is associated with excessive proinflammatory cytokine production. Notably, the severity and mortality of natural infections with Plasmodium are higher in males than females, suggesting that sexual hormones influence both the pathogenesis of and immune response in CM. However, no studies on inflammation mediators in the brains of both sexes have been reported. In this work, the mRNA expression levels of the proinflammatory cytokines IL-1ß, IFN-γ, TNF-α, and IL-2 were measured in the preoptic area, hypothalamus, hippocampus, olfactory bulb, frontal cortex, and lateral cortex regions of gonadectomized female and male CBA/Ca mice infected with P. berghei ANKA (a recognized experimental CM model). Our findings demonstrate that both infection with P. berghei ANKA and gonadectomy trigger a cerebral sex dimorphic mRNA expression pattern of the cytokines IL-1ß, TNF-α, IFN-γ, and IL-2. This dimorphic cytokine pattern was different in each brain region analysed. In most cases, infected males exhibited higher mRNA expression levels than females, suggesting that sexual hormones differentially regulate the mRNA expression of proinflammatory cytokines in the brain and the potential use of gonadal steroids or their derivates in the immunomodulation of cerebral malaria.


Asunto(s)
Encéfalo/metabolismo , Citocinas/metabolismo , Hormonas Esteroides Gonadales/metabolismo , Malaria Cerebral/metabolismo , Plasmodium berghei/patogenicidad , ARN Mensajero/metabolismo , Animales , Femenino , Inmunomodulación/fisiología , Interferón gamma/metabolismo , Interleucina-1beta/metabolismo , Interleucina-2/metabolismo , Malaria Cerebral/genética , Masculino , Ratones , Ratones Endogámicos CBA , Orquiectomía , Ovariectomía , Factor de Necrosis Tumoral alfa/metabolismo
16.
Gac Med Mex ; 154(1): 111-117, 2018.
Artículo en Español | MEDLINE | ID: mdl-29420526

RESUMEN

French intervention in Mexico (1861-1867) is particularly full of episodes of patriotic heroism in terms of military, politic and, even, religious affairs, however this history is also rich in episodes related to diseases and the evolution of Mexican scientific medicine practice, epidemics such as typhus (nowadays knows as rickettsiosis), yellow fever, or cholera. Principally, this context outlined the Mexican history and influenced the course of the nation. The epidemics served as fertile land for the development of medicine science leading by prominent physicians, particularly by doctor Miguel Francisco Jiménez.


El periodo comprendido entre 1861 y 1867, marcado por la ocupación extranjera, particularmente por Francia, es sin lugar a dudas rico en gestas de patriotismo sin igual en la historia de México por la coyuntura política, militar e incluso religiosa del periodo en cuestión; sin embargo, poco se ha abordado de manera concreta el estado que guardaban la salud y la ciencia médica en dicho periodo, lleno de episodios sumamente interesantes en cuanto a epidemias como el tifo, la fiebre amarilla o el cólera, sobre todo cuando estas enfermedades afectaron y marcaron el rumbo de la historia nacional, a la par con el desarrollo de la naciente medicina científica mexicana encabezada por varios médicos, en especial por el Dr. Miguel Francisco Jiménez.


Asunto(s)
Historia de la Medicina , Tifus Epidémico Transmitido por Piojos/historia , Fiebre Amarilla/historia , Francia , Historia del Siglo XIX , México
17.
Rev Esp Enferm Dig ; 109(11): 796-798, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29027468

RESUMEN

Inflammatory bowel disease (IBD) patients are at an increased risk of developing colorectal cancer (CRC), which is thought to develop via the adenoma-carcinoma pathway. Since the discovery of the serrated carcinogenesis pathway and serrated polyposis syndrome (SPS), the incidence of carcinomas arising from serrated lesions in IBD patients has increased. We report three cases of long-standing IBD patients with associated serrated polyposis syndrome. At present, the pathophysiology of serrated lesions in IBD patients is not fully understood and there is a lack of strong evidence to confirm whether the manifestation of both conditions represents an increased risk of developing cancer. Therefore, more accurate surveillance guidelines are needed and are being actively investigated at present.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Poliposis Intestinal/complicaciones , Adulto , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Pólipos del Colon/patología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/patología , Endoscopía Gastrointestinal , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/patología , Poliposis Intestinal/patología , Persona de Mediana Edad
18.
Inorg Chem ; 55(11): 5592-602, 2016 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-27187280

RESUMEN

The diazoalkane complexes [Ru(η(5)-C5Me5)(N2CAr1Ar2){P(OR)3}L]BPh4 (1-4) [R = Me, L = P(OMe)3 (1); R = Et, L = P(OEt)3 (2); R = Me, L = PPh3 (3); R = Et, L = PPh3 (4); Ar1 = Ar2 = Ph (a); Ar1 = Ph, Ar2 = p-tolyl (b); Ar1Ar2 = C12H8 (c); Ar1 = Ph, Ar2 = PhC(O) (d)] and [Ru(η(5)-C5Me5){N2C(C12H8)}{PPh(OEt)2}(PPh3)]BPh4 (5c) were prepared by allowing chloro-compounds RuCl(η(5)-C5Me5)[P(OR)3]L to react with the diazoalkane Ar1Ar2CN2 in the presence of NaBPh4. Treatment of complexes 1-4 with H2O afforded 1,2-diazene derivatives [Ru(η(5)-C5Me5)(η(2)-NH═NH){P(OR)3}L]BPh4 (6-9) and ketone Ar1Ar2CO. A reaction path involving nucleophilic attack by H2O on the coordinated diazoalkane is proposed and supported by density functional theory calculations. The complexes were characterized spectroscopically (IR and (1)H, (31)P, (13)C, (15)N NMR) and by X-ray crystal structure determination of [Ru(η(5)-C5Me5)(N2CC12H8){P(OEt)3}2]BPh4 (2c) and [Ru(η(5)-C5Me5)(η(2)-NH═NH){P(OEt)3}2]BPh4 (7).

19.
Inorg Chem ; 54(5): 2091-3, 2015 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-25695769

RESUMEN

Diazoalkane complexes [Ru(η(5)-C5Me5)(N2CAr1Ar2)(PPh3){P(OR)3}]BPh4 [R = Me (1), Et (2); Ar1 = Ar2 = Ph (a); Ar1 = Ph, Ar2 = p-tolyl (b); Ar1Ar2 = C12H8 (c)] were prepared by allowing chloro complexes RuCl(η(5)-C5Me5)(PPh3)[P(OR)3] to react with diazoalkane Ar1Ar2CN2 in ethanol. The treatment of compounds 1 and 2 with H2O afforded 1,2-diazene derivatives [Ru(η(5)-C5Me5)(η(2)-NH═NH)(PPh3){P(OR)3}]BPh4 (3 and 4) and ketone Ar1Ar2CO. A reaction path involving nucleophilic attack by H2O on the coordinated diazoalkane is proposed. The complexes were characterized spectroscopically (IR and NMR) and by X-ray crystal structure determination of [Ru(η(5)-C5Me5)(η(2)-NH═NH)(PPh3){P(OMe)3}]BPh4 (3).

20.
Gac Med Mex ; 151(3): 403-15, 2015.
Artículo en Español | MEDLINE | ID: mdl-26089278

RESUMEN

Glioblastoma multiforme is one of the most aggressive central nervous system tumors and with worse prognosis. Until now,treatments have managed to significantly increase the survival of these patients, depending on age, cognitive status, and autonomy of the individuals themselves. Based on these parameters, both initial or recurrence treatments are performed, as well as monitoring of disease by imaging studies. When the patient enters the terminal phase and curative treatments are suspended, respect for the previous wishes of the patient and development and implementation of palliative therapies must be guaranteed.


Asunto(s)
Glioblastoma/terapia , Cuidados Paliativos/métodos , Grupo de Atención al Paciente/organización & administración , Glioblastoma/patología , Humanos , México , Recurrencia Local de Neoplasia , Tasa de Supervivencia , Cuidado Terminal/métodos
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