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1.
J Chem Phys ; 158(23)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37318163

RESUMO

Polariton chemistry has emerged as an appealing branch of synthetic chemistry that promises mode selectivity and a cleaner approach to kinetic control. Of particular interest are the numerous experiments in which reactivity has been modified by virtue of performing the reaction inside infrared optical microcavities in the absence of optical pumping; this effort is known as "vibropolaritonic chemistry." The optimal conditions for these observations are (1) resonance between cavity and reactive modes at normal incidence (k = 0) and (2) a monotonic increase of the effect with the concentration of emitters in the sample. Importantly, vibropolaritonic chemistry has only been experimentally demonstrated in the so-called "collective" strong coupling regime, where there is a macroscopic number of molecules (rather than a single molecule) coupled to each photon mode of the microcavity. Strikingly, efforts to understand this phenomenon from a conceptual standpoint have encountered several roadblocks, and no single, unifying theory has surfaced thus far. This Perspective documents the most relevant approaches taken by theorists, laying out the contributions and unresolved challenges from each work. We expect this Perspective to not only serve as a primer for experimentalists and theorists alike but also inform future endeavors in the quest for the ultimate formalism of vibropolaritonic chemical kinetics.

2.
Rev Gastroenterol Mex ; 78(4): 225-30, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24290317

RESUMO

BACKGROUND: Peroral endoscopic myotomy has recently been developed and performed on patients with good results. AIMS: To evaluate the technical feasibility of peroral endoscopic full-thickness and partial thickness myotomy in a porcine model. MATERIAL AND METHODS: Eighteen criollo pigs were randomly assigned to 2 groups: group A (partial-thickness myotomy) and group B (full-thickness myotomy). The mucosal defect proximal to the myotomy site was left open. On the seventh postoperative day the pig was euthanized and follow-up surgical exploration was performed. The duration of each procedure, postoperative progression of the animal, complications, and anatomopathologic findings were registered. RESULTS: The procedure was viable in all the pigs. The mean surgery duration was 81±35.3min (group A 51.11±11.12, group B 111±22.61; P<.05). The main complication during myotomy was subcutaneous emphysema (16%). The histopathologic study of the group A surgical specimens reported complete circular myotomy in all cases, and complete circular and longitudinal myotomy was reported in 100% of the group B sample. CONCLUSIONS: The endoscopic myotomy technique is feasible. Endoscopic partial-thickness myotomy was associated with shorter surgery duration and better results during the intraoperative period and the 7-day follow-up.


Assuntos
Endoscopia Gastrointestinal/métodos , Esôfago/cirurgia , Boca/cirurgia , Anestesia , Animais , Endoscopia Gastrointestinal/efeitos adversos , Acalasia Esofágica/cirurgia , Esfíncter Esofágico Inferior/cirurgia , Feminino , Músculos/cirurgia , Cirurgia Endoscópica por Orifício Natural , Hemorragia Pós-Operatória , Suínos
3.
Rev Gastroenterol Mex ; 74(2): 88-93, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19666288

RESUMO

BACKGROUND: The intestinal gastric cancer is preceded by a sequence of pathological changes whose link is mucosal atrophy. The modified Sydney system for atrophy is a parameter not reproducible among pathologists. AIM: To know the interobserver variability using the OLGA system (Operative Link on Gastritis Assessment). METHODS: We selected 116 histologic slides. Sixty cases of both types of atrophy and 56 without atrophy were included. Three general pathologists, interested in gastrointestinal biopsies independently review the slides and established a diagnosis. For statistical analyses we employed singles frequencies in order to describe the individual diagnosis and the kappa test for evaluate the concordance between 2 and 4 observers with 2 and 3 categories. RESULTS: The global concordance has a kappa index of 0.48 (IC 95% 0.4-0.57). When we compared two pathologists the kappa index varies from 0.82(IC 95% 0.73-0.91) to 0.36 (IC 95% 0.22-0.5). The consensus among three pathologists was achieved in 25 out 30 slides in the metaplastic variety and 11 out 30 for the non-metaplastic type. The concordance for the atrophy scale has a kappa index between 0.2 and 0.5. CONCLUSION: The problematic atrophic evaluation with the Sydney system justify every effort to improve the interobserver evaluation. The OLGA system seems reproducible, although laborious,it requires a careful application, but with daily practice it could be applied easier. The clinician acceptation becomes crucial.


Assuntos
Gastrite Atrófica/patologia , Estômago/patologia , Atrofia/epidemiologia , Feminino , Gastrite Atrófica/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador
4.
Gac Med Mex ; 128(4): 411-4, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1307990

RESUMO

The amount of neuroendocrine granules in microgranular cells of salivary glands were investigated in necropsies of 20 non-insulin dependent diabetics (NIDDM) and in 20 non-diabetic subjects with Grimelius and Fontana-Masson stainings. Granules in serous acini, and intercalated ducts were observed in both groups; however, a significant higher number of granules and microgranular cells were observed in NIDDM subjects as compared with non-diabetics. Both parotid and submaxillary glands were significantly heavier in NIDDM than in the non-diabetic group. These granules may be related to immunoreactive glucagon which has been found in submaxillary glands of rodents and might play a role in the pathogenesis of NIDDM. Further investigations should be performed to clarify whether these cells are the site of glucagon synthesis and also clarify the pathogenesis of NIDDM.


Assuntos
Grânulos Citoplasmáticos/patologia , Diabetes Mellitus Tipo 2/patologia , Glândula Parótida/patologia , Glândula Submandibular/patologia , Adulto , Idoso , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Neurossecretores/patologia , Tamanho do Órgão
5.
Ginecol Obstet Mex ; 59: 211-24, 1991 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-1769604

RESUMO

Chorionic villus sampling (CVS) has a promising future about early detection of fetal abnormalities. It has the potential to become a major tool in the prenatal diagnosis and therapy of genetic disorders. Villus samples can be analyzed by means of cytogenetic, biochemical or molecular technics. Information available at present indicates fetal loss rate should be in the same proportion than amniocentesis. CVS appears to be a reasonably safe and reliable method of prenatal diagnosis in the first trimester of pregnancy. This procedure is setting as fast as it is possible like an excellent alternative to amniocentesis.


Assuntos
Amostra da Vilosidade Coriônica , Aberrações Cromossômicas/diagnóstico , Doenças Fetais/diagnóstico , Doenças Genéticas Inatas/diagnóstico , Amostra da Vilosidade Coriônica/efeitos adversos , Amostra da Vilosidade Coriônica/história , Amostra da Vilosidade Coriônica/métodos , Transtornos Cromossômicos , DNA Recombinante , Feminino , História do Século XX , Humanos , Valor Preditivo dos Testes , Gravidez
11.
Rev. méd. IMSS ; 20(4): 363-5, 1982.
Artigo em Espanhol | LILACS | ID: lil-9438

RESUMO

Presentamos el caso de un paciente quien despues de un traumatismo en la region retroauricular izquierda desarrolla un angioliomioma extraido quirurgicamente. Actualmente el paciente se encuentra libre de sintomatologia. Estos tumores son dificiles de diagnosticar clinicamente por la falta de sintomatologia especifica y lo raro de su presentacion; este es el segundo caso informado en la literatura mundial con esta localizacion. El tratamiento que se sugiere es el quirurgico, no se presentan recurrencias cuando su extirpacion es total


Assuntos
Adolescente , Humanos , Masculino , Neoplasias da Orelha , Leiomioma
13.
Rev Gastroenterol Mex ; 46(1): 1-5, 1981.
Artigo em Espanhol | MEDLINE | ID: mdl-7280456

RESUMO

After major surgery some patients, especially those with an infectiouss process or sepsis, develop jaundice which has been called reactive hepatitis, toxic hepatitis, septic hepatitis or benign postoperative cholestasis; these terms do not have a very precise connotation. Eighty patients with postoperative sepsis and jaundice where studied, excluding those with liver or biliary tract disease, hepato-toxic drugs or repeated halogenated anesthetics. All of them had complete laboratory tests, cultures and percutaneous liver biopsy when it was feasible. Thirty five patients were submitted to percutaneous liver biopsy and they are the material for this paper. There was no correlation with the type and duration of the operation, postoperative complications, shock or kind of anesthesia. The main laboratory changes were leukocytosis, neutrophilia, elevation of the bilirubins mainly the direct type and increase of the alkaline phosphatase; transaminases were within normal limits. Cultures were positive in 76% of the cases predominating E. coli, Pseudomonas a. and Proteus, anaerobics were present in 22.8% of the cases. The liver biopsy showed lymphoctic infiltration, hyperplasia of the Kupffer cells, hepatic regeneration and turbid tumefaction; pericholangitis, focal necrosis, retention of pigment and steatosis were less frequent. We consider that the best denomination of these complications is benign postoperative cholestasis.


Assuntos
Infecções Bacterianas/complicações , Hepatite/etiologia , Complicações Pós-Operatórias , Sepse/complicações , Adolescente , Adulto , Idoso , Biópsia por Agulha , Colestase Intra-Hepática/etiologia , Colestase Intra-Hepática/patologia , Feminino , Hepatite/patologia , Humanos , Fígado/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Circulação Esplâncnica
14.
Rev. invest. clín ; 33(4): 399-403, 1981.
Artigo em Espanhol | LILACS | ID: lil-7045

RESUMO

Se informan tres casos de metamorfosis grasa aguda del embarazo (MGAE), vistos en el Hospital de Infectologica del IMSS.Las pacientes cursaban las ultimas semanas de su primera gestacion cuando iniciaron la sintomatologia.El parto se desencandeno o fue inducido cuando las manigestaciones clinicas de MGAE se encontraban bien establecidas en dos de ellas cuyos productos fallecieron; en la otra paciente la sintomatologia se intensifico despues del parto y el producto nacio vivo.Todas fueron enviadas de hospitales de ginecobstetricia con diagnostico de hepatitis viral.Ninguna de ellas tenia antecedentes de haber recibido tetraciclinas. Se describe el cuadro clinico, que es indistinguible de la hepatitis fulminante y puede confundirse tambien con toxemia, asi como aspectos relacionados a la fisiopatogenia y manejo terapeutico


Assuntos
Fígado Gorduroso , Complicações na Gravidez
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