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1.
Rev Gastroenterol Peru ; 43(1): 69-73, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37226074

RESUMO

Intestinal intussusception in adult patients is a rare entity, which corresponds to about 5% of all causes of intestinal obstruction, its diagnosis is not easy given the lack of specific symptoms of patients who present it. This is mainly based on the findings of imaging studies, surgical management is the cornerstone of treatment of this pathology and its success will be determined by timely diagnosis as well as by the expertise of the treating surgeon. This article presents the case of a 62-year-old male patient who consults due to nonspecific abdominal pain and irritative urinary symptoms, who due to persistence of abdominal pain despite medical management is taken to surgery where it is diagnosed intraoperatively. an intestinal intussusception at the level of the distal ileum.


Assuntos
Obstrução Intestinal , Intussuscepção , Neoplasias , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Intussuscepção/diagnóstico , Intussuscepção/etiologia , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/etiologia , Dor Abdominal , Íleo
2.
J Am Chem Soc ; 142(14): 6499-6504, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32156107

RESUMO

The first total synthesis of the resveratrol tetramers vitisin A and vitisin D is reported. Electrochemical generation and selective dimerization of persistent radicals is followed by thermal isomerization of the symmetric C8b-C8c dimer to the C3c-C8b isomer, providing rapid entry into the vitisin core. Computational results suggest that this synthetic approach mimics Nature's strategy for constructing these complex molecules. Sequential acid-mediated rearrangements consistent with the proposed biogenesis of these compounds afford vitisin A and vitisin D. The rapid synthesis of these complex molecules will enable further study of their pharmacological potential.


Assuntos
Benzofuranos/síntese química , Fenóis/síntese química , Humanos , Estrutura Molecular
3.
Chem Soc Rev ; 47(21): 7851-7866, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30101272

RESUMO

Free radical intermediates have intrigued chemists since their discovery, and an ever-increasing appreciation for their unique reactivity has resulted in the widespread utilization of these species throughout the field of chemical synthesis. This is most evident from the recent surge in the application of intermolecular radical reactions that feature in complex molecule syntheses. This tutorial review will discuss the diverse methods utilized for radical generation and reactivity to form critical bonds in natural product total synthesis. In particular, stabilized (e.g. benzyl) and persistent (e.g. TEMPO) radicals will be the primary focus.

4.
Angew Chem Int Ed Engl ; 57(52): 17125-17129, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30474921

RESUMO

A simple method for the dimerization of phenylpropenoid derivatives is reported. It leverages electrochemical oxidation of p-unsaturated phenols to access the dimeric materials in a biomimetic fashion. The mild nature of the transformation provides excellent functional group tolerance, resulting in a unified approach for the synthesis of a range of natural products and related analogues with excellent regiocontrol. The operational simplicity of the method allows for greater efficiency in the synthesis of complex natural products. Interestingly, the quinone methide dimer intermediates are potent radical-trapping antioxidants; more so than the phenols from which they are derived-or transformed to-despite the fact that they do not possess a labile H-atom for transfer to the peroxyl radicals that propagate autoxidation.


Assuntos
Antioxidantes/química , Técnicas Eletroquímicas , Indolquinonas/química , Fenilpropionatos/síntese química , Dimerização , Estrutura Molecular , Fenilpropionatos/química
5.
Front Neurosci ; 16: 726467, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651628

RESUMO

Hypertension is a main cause of death in the United States with more than 103 million adults affected. While pharmacological treatments are effective, blood pressure (BP) remains uncontrolled in 50-60% of resistant hypertensive subjects. Using a custom-wired miniature electrode, we previously reported that deep peroneal nerve stimulation (DPNS) elicited acute cardiovascular depressor responses in anesthetized spontaneously hypertensive rats (SHRs). Here, we further study this effect by implementing a wireless system and exploring different stimulation parameters to achieve a maximum depressor response. Our results indicate that DPNS consistently induces a reduction in BP and suggests that renal sympathetic nerve activity (RSNA) is altered by this bioelectronic treatment. To test the acute effect of DPNS in awake animals, we developed a novel miniaturized wireless microchannel electrode (w-µCE), with a Z-shaped microchannel through which the target nerves slide and lock into the recording/stimulation chamber. Animals implanted with w-µCE and BP telemetry systems for 3 weeks showed an average BP of 150 ± 14 mmHg, which was reduced significantly by an active DPNS session to 135 ± 8 mmHg (p < 0.04), but not in sham-treated animals. The depressor response in animals with an active w-µCE was progressively returned to baseline levels 14 min later (164 ± 26 mmHg). This depressor response was confirmed in restrained fully awake animals that received DPNS for 10 days, where tail-cuff BP measurements showed that systolic BP in SHR lowered 10% at 1 h and 16% 2 h after the DPNS when compared to the post-implantation baseline. Together, these results support the use of DPN neuromodulation as a possible strategy to lower BP in drug-resistant hypertension.

6.
Chem Sci ; 11(22): 5676-5689, 2020 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-32832049

RESUMO

Hydrogen atom transfer (HAT) is the mechanism by which the vast majority of radical-trapping antioxidants (RTAs), such as hindered phenols, inhibit autoxidation. As such, at least one weak O-H bond is the key structural feature which underlies the reactivity of phenolic RTAs. We recently observed that quinone methide dimers (QMDs) synthesized from hindered phenols are significantly more reactive RTAs than the phenols themselves despite lacking O-H bonds. Herein we describe our efforts to elucidate the mechanism by which they inhibit autoxidation. Four possible reaction paths were considered: (1) HAT from the C-H bonds on the carbon atoms which link the quinone methide moieties; (2) tautomerization or hydration of the quinone methide(s) in situ followed by HAT from the resultant phenolic O-H; (3) direct addition of peroxyl radicals to the quinone methide(s), and (4) homolysis of the weak central C-C bond in the QMD followed by combination of the resultant persistent phenoxyl radicals with peroxyl radicals. The insensitivity of the reactivity of the QMDs to substituent effects, solvent effects and a lack of kinetic isotope effects rule out the HAT reactions (mechanisms 1 and 2). Simple (monomeric) quinone methides, to which peroxyl radicals add, were found to be ca. 100-fold less reactive than the QMDs, ruling out mechanism 3. These facts, combined with the poor RTA activity we observe for a QMD with a stronger central C-C bond, support mechanism 4. The lack of solvent effects on the RTA activity of QMDs suggests that they may find application as additives to materials which contain H-bonding accepting moieties that can dramatically suppress the reactivity of conventional RTAs, such as phenols. This reactivity does not extend to biological membranes owing to the increased microviscosity of the phospholipid bilayer, which suppresses QMD dissociation in favour of recombination. Interestingly, the simple QMs were found to be very good RTAs in phospholipid bilayers - besting even the most potent form of vitamin E.

7.
Rev. gastroenterol. Perú ; 43(1)ene. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1441885

RESUMO

La intususcepción intestinal en pacientes adultos es una entidad infrecuente, la cual corresponde alrededor del 5% de todas las causas de obstrucción intestinal. Su diagnóstico no es fácil, dado lo poco especifico de los síntomas de los pacientes que la presentan; este se sustenta principalmente en los hallazgos de los estudios de imagen. El manejo quirúrgico es la piedra angular del tratamiento de esta patología, y su éxito va a estar determinado por el diagnóstico oportuno y la experticia del cirujano tratante. En este artículo se presenta el caso de un paciente masculino de 62 años, que consulta por cuadro de dolor abdominal inespecífico y síntomas urinarios irritativos, el cual por persistencia del dolor abdominal pese al manejo medico es llevado a cirugía, donde se diagnostica de manera intraoperatoria una invaginación intestinal a nivel de íleon distal.


Intestinal intussusception in adult patients is a rare entity, which corresponds to about 5% of all causes of intestinal obstruction, its diagnosis is not easy given the lack of specific symptoms of patients who present it. This is mainly based on the findings of imaging studies, surgical management is the cornerstone of treatment of this pathology and its success will be determined by timely diagnosis as well as by the expertise of the treating surgeon. This article presents the case of a 62-year-old male patient who consults due to nonspecific abdominal pain and irritative urinary symptoms, who due to persistence of abdominal pain despite medical management is taken to surgery where it is diagnosed intraoperatively. an intestinal intussusception at the level of the distal ileum.

8.
Oncología (Guayaquil) ; 30(1): 53-65, Abril. 2020.
Artigo em Espanhol | LILACS | ID: biblio-1140880

RESUMO

Introducción: Lasupervivencia de pacientes con Cáncer de Cérvix se influencia por los estadíos clínicos de laenfermedad y por su histología. El objetivo de este estudio fue establecer la supervivencia en un grupo depacientes deun centro oncológico en Cuenca-Ecuador. Métodos:Es un estudio descriptivo, retrospectivo, analítico, en el cual se recopiló información de las historias clínicas y registros físicos del sistema médico de SOLCA ­Cuencapara establecer la Supervivencia durante el periodo 2009-2013.Se describen variables variables demográficas y clínicas (Tipode histología y estadío), Se compara la supervivencia entre laspacientes con estas variables. Resultados:Se incluyeron 150casos,edad media de 57.1 ±14.0años. El estado civil más prevalente fue el "casada"n=75/150 (50%), de procedencia Urbanan=83/150 (55.3%)de la provincia del Azuay (48.0%). El tipo histológico más prevalente fue el Cáncer epidermoide (92%), 60% en estadío clínico IIB. Mortalidad de 7casos. SupervivenciaGlobal (SG) 57.6 meses; con un EE de 0.88 y un IC 95% con rango de 55.9 a 59.4meses.SG en el estadio IIB fue de58.4 meses(EE: 0.91; IC 95%:56.63 ­60.20). En el estadio IIIB fue de 56.3 meses(EE: 1.85; IC 95%: 52.71 ­59.96), no se encontró diferencia estadística (P= 0.45). La SGfue mayor en el carcinoma epidermoide (Media: 58.2 meses; EE: 0.79, IC 95%: 57.70 a 59.81) en relación a la variante adenocarcinoma (Media: 50.08 meses; EE: 6.26; IC 95%: 37.81 a 62.36), con significancia estadística (P=0.045). Conclusión:La supervivencia global fue de 57.6 meses, con diferencia de supervivencia para el tipo histológico, siendo el mayor para carcinoma epidermoide 8 meses menos para el adenocarcinoma. No hubo diferencias entre la supervivencia entre estadíos clínicos IIB y IIIB


Introduction: The survival of patients with Cervical Cancer is influenced by the clinical stages of the disease and its histology. The objective of this study was to establish survival in a group of patients from an oncology center in Cuenca-Ecuador. Methods: It is a descriptive, retrospective, analytical study, in which information was collectedfrom the medical records and physical records of the SOLCA -Cuenca medical system to establish Survival during the period 2009-2013. Demographic and clinical variables are described ( Type of histology and stage), Survival is compared between patients with these variables. Results: 150 cases were included, mean age of 57.1 ± 14.0 years. The most prevalent marital status was "married" n = 75/150 (50%), of urban origin n = 83/150 (55.3%) from the province of Azuay (48.0%). The most prevalent histological type was epidermoid cancer (92%), 60% in clinical stage IIB. Mortality of 7 cases. Overall Survival (OS) 57.6 months; with a SE of 0.88 and a 95% CI with a range of 55.9 to 59.4 months. OS in stage IIB was 58.4 months (SE: 0.91; 95% CI: 56.63 -60.20). In stage IIIB it was 56.3 months (SE: 1.85; 95% CI: 52.71 -59.96), no statistical difference was found (P = 0.45). OS was higher in squamous cell carcinoma (Mean: 58.2 months; SE: 0.79, 95% CI: 57.70 to 59.81) in relation to the adenocarcinoma variant (Mean: 50.08 months; SE: 6.26; 95% CI: 37.81 to 62.36), with statistical significance (P= 0.045). Conclusion: Overall survival was 57.6 months, with a survival difference for histological type, the longest being for squamous cell carcinoma 8 months less for adenocarcinoma. There were no differences between survival between clinical stages IIB and IIIB


Assuntos
Humanos , Análise de Sobrevida , Displasia do Colo do Útero , Colo do Útero
9.
Rev. cuba. invest. bioméd ; 37(2): 9-17, abr.-jun. 2018. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1003921

RESUMO

Introducción: La relación causa / efecto entre el embarazo y la enfermedad periodontal resulta muy contradictorio en la literatura. Algunos autores niegan que exista esta relación, mientras otros la afirman. Objetivo: Identificar la presencia de Enfermedad Periodontal en gestantes del primer y tercer trimestre, teniendo en cuenta la edad y la higiene bucal de las mismas. Métodos: La muestra estuvo integrada por 106 gestantes del primer y tercer trimestre del embarazo. Las mismas fueron reunidas de acuerdo a los siguientes grupos de edades: Adolescentes, adultas jóvenes y adultas de más de 35 años. A todas las gestantes de la muestra se les efectuó un examen estomatológico para diagnosticar las pacientes portadoras de Enfermedad Periodontal, las formas clínicas presentadas, así como evaluar la calidad de la higiene bucal. Resultados: Se comprobó que 36 de las gestantes eran portadoras de Enfermedad Periodontal: 34 presentaban gingivitis y dos periodontitis. La forma clínica más abundante fue la gingivitis fibro-edematosa. De las 36 gestantes enfermas, 33 eran adultas jóvenes y tres, mayores de 35 años. Ninguna de las adolescentes presentó EP. Del total de gestantes, 20 se encontraban en el primer trimestre y 16 en el tercero. De las 36 pacientes enfermas 29 presentaron higiene bucal deficiente para un 80,55 por ciento y sólo siete mostraban una higiene bucal eficiente para un 19,44 por ciento. Conclusiones: La Enfermedad Periodontal es frecuente entre las gestantes del primer y tercer trimestre a lo cual contribuye la mala higiene bucal, la edad, como también la elevación de las hormonas durante el embarazo(AU)


Introduction: The cause / effect relationship between pregnancy and periodontal disease is very contradictory in the literature. Some authors deny that this relationship exists, while others affirm it. Objective: To identify the presence of Periodontal Disease in first and third trimester pregnant women, taking into account their age and oral hygiene. Methods: The sample consisted of 106 pregnant women from the first and third trimesters of pregnancy. They were collected according to the following age groups: Adolescents, young adults and adults over 35 years of age. All the pregnant women in the sample underwent a stomatological examination to diagnose the patients carrying Periodontal Disease, the presented clinical forms, as well as to evaluate the quality of the oral hygiene. Results: It was found that 36 of the pregnant women were carriers of Periodontal Disease: 34 had gingivitis and two periodontitis. The most abundant clinical form was fibro-edematous gingivitis. Of the 36 pregnant women, 33 were young adults and three were over 35 years old. None of the adolescents presented EP. Of the total of pregnant women, 20 were in the first quarter and 16 in the third. Of the 36 sick patients, 29 had poor oral hygiene for 80.55 percent and only seven showed efficient oral hygiene for 19.44 percent. Conclusions: Periodontal disease is common among pregnant the first and third quarter which contributes to poor oral hygiene, age, as well as elevated hormones during pregnancy(AU)


Assuntos
Humanos , Feminino , Gravidez , Adolescente , Adulto , Doenças Periodontais/complicações , Doenças Periodontais/diagnóstico , Doenças Periodontais/epidemiologia , Índice de Higiene Oral , Epidemiologia Descritiva , Estudos Transversais
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