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1.
Nature ; 620(7974): 516-520, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37488359

RESUMEN

Terrestrial and sub-Neptune planets are expected to form in the inner (less than 10 AU) regions of protoplanetary disks1. Water plays a key role in their formation2-4, although it is yet unclear whether water molecules are formed in situ or transported from the outer disk5,6. So far Spitzer Space Telescope observations have only provided water luminosity upper limits for dust-depleted inner disks7, similar to PDS 70, the first system with direct confirmation of protoplanet presence8,9. Here we report JWST observations of PDS 70, a benchmark target to search for water in a disk hosting a large (approximately 54 AU) planet-carved gap separating an inner and outer disk10,11. Our findings show water in the inner disk of PDS 70. This implies that potential terrestrial planets forming therein have access to a water reservoir. The column densities of water vapour suggest in-situ formation via a reaction sequence involving O, H2 and/or OH, and survival through water self-shielding5. This is also supported by the presence of CO2 emission, another molecule sensitive to ultraviolet photodissociation. Dust shielding, and replenishment of both gas and small dust from the outer disk, may also play a role in sustaining the water reservoir12. Our observations also reveal a strong variability of the mid-infrared spectral energy distribution, pointing to a change of inner disk geometry.

2.
Reproduction ; 146(6): 615-23, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24062569

RESUMEN

Potassium voltage-gated channel, subfamily H (eag-related), member 1 (KCNH1) potassium channels are potential tumour markers and cancer therapeutic targets and are up-regulated by oestrogens and human papilloma virus (HPV) oncogenes. However, the role of KCNH1 in normal tissues is poorly understood, and its expression in pregnancy is unknown. We wondered whether KCNH1 channels are expressed in cervical cells from pregnant patients and whether progesterone (P4) regulates KCNH1. The association with HPV was also investigated. KCNH1 protein expression was studied by immunocytochemistry in liquid-based cervical cytologies; 93 samples were obtained from pregnant patients at different trimesters, and 15 samples were obtained from non-pregnant women (controls). The presence of HPV was studied by PCR with direct sequencing and nested multiplex PCR. HeLa cervical cancer cells were transfected with human progesterone receptor-B (PR-B) and treated with P4. KCNH1 mRNA expression in these cultures was studied by real-time PCR. KCNH1 protein was detected in 100% of the pregnancy samples and in 26% of the controls. We found 18 pregnant patients infected with HPV and detected 14 types of HPV. There was no association between the percentage of cells expressing KCNH1 and either the presence or type of HPV. P4 induced KCNH1 mRNA and protein expression in cells transfected with human PR-B. No regulation of KCNH1 by P4 was observed in non-transfected cells. We show for the first time the expression of an ion channel during human pregnancy at different trimesters and KCNH1 regulation by P4 in human cells. These data raise a new research field for KCNH1 channels in human tissues.


Asunto(s)
Cuello del Útero/metabolismo , Canales de Potasio Éter-A-Go-Go/genética , Embarazo/genética , Progesterona/farmacología , Adolescente , Adulto , Cuello del Útero/efectos de los fármacos , Cuello del Útero/patología , Canales de Potasio Éter-A-Go-Go/metabolismo , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Papillomaviridae/aislamiento & purificación , Embarazo/metabolismo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/genética , Complicaciones Infecciosas del Embarazo/metabolismo , Receptores de Progesterona/genética , Frotis Vaginal , Adulto Joven
3.
Enferm. univ ; 6(5): 15-19, Jul. 2009. tab, graf
Artículo en Español | LILACS, BDENF | ID: biblio-1028527

RESUMEN

Ante un brote de una enfermedad infecto-contagiosa, el estudio de contactos limita la transmisión de esta. El objetivo de este trabajo fue identificar a los contactos de los posibles casos de influenza en trabajadores de la UNAM para establecer una comunicación y proporcionar educación para la salud sobre medidas higiénicas. Material y métodos: Se elaboró un cuestionario, se estableció contacto con los casos por vía telefónica y se llevó a cabo una visita domiciliaria. Se llevó a cabo un análisis descriptivo de los datos y una descripción de las experiencias y percepciones durante las visitas. Resultados: Se identificó que la mayoría de los contactos eran familiares directos de los casos, que no contaban con un esquema de vacunación completo, ni contra la influenza y la frecuencia de síntomas varió de 1 hasta 4. Comentarios finales: Ante una situación de este tipo (la Pandemia del Virus de la Influenza Humana A (H1N1)) el papel de la enfermera en salud pública es de suma importancia no solo en la búsqueda de los casos y sus contactos, sino también en la orientación y educación de la población en relación a las medidas preventivas.


In the view of an infectious and contagious disease epidemic, the identification of the contacts limits its transmission. The objective of this work was to identify the contacts of the possible cases of UNAM workers in order to establish communication and provide health education about hygiene measures. Material and methods: A questionnaire was prepared, telephone contact was established with the cases, and a home visit was arranged. A descriptive analysis of the data was carried out, as well as, a description of the experiences and perception during the home visit. Results: Most identified contacts were relatives of the cases, which did not have a complete vaccine scheme, no even against influenza, and the frequency of symptoms varied between 1 a 4. Final comments: In a situation like this (A(H1N1) human influenza virus pandemic) the public health nurse roll is of great importance, not just in the identification of the cases and its contacts, but also in the orientation and education of the population in relation to preventive measures.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Gripe Humana , Prevención Primaria , Salud Pública
4.
Ann Oncol ; 13(8): 1212-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12181244

RESUMEN

BACKGROUND: Randomized studies comparing induction chemotherapy followed by surgical resection with radiation alone found that the neoadjuvant approach produces better results. So far, this latter modality has not been compared with standard concomitant chemoradiation. The objective of this report was to compare the results of two consecutive phase II studies: neoadjuvant chemotherapy followed by surgery or chemoradiation for the unresectable cases versus standard cisplatin-based chemoradiation. PATIENTS AND METHODS: From February 1999 to July 1999, 41 patients with cervical carcinoma, stages IB2-IIIB, were treated with neoadjuvant chemotherapy. Treatment consisted of three 21-day courses of cisplatin 100 mg/m(2) on day 1 and gemcitabine 1000 mg/m(2) on days 1 and 8, followed by either surgery or concomitant chemoradiation for the non-operable cases. From August 1999 to December 1999, an equal number of patients having comparable clinicopathological characteristics were treated with six weekly courses of cisplatin 40 mg/m(2) during standard pelvic radiation. RESULTS: A total of 82 patients were analyzed. Both groups were similar with regard to age, histology, International Federation of Gynecology and Obstetrics (FIGO) stage, tumor size, pretreatment hemoglobin levels, parametrial infiltration and performance status. In the neoadjuvant arm the overall response rate to induction chemotherapy was 95% (95% confidence interval 88% to 100%). Twenty-three patients had surgery and 14 underwent chemoradiation. In the definitive chemoradiation study, 38 patients completed treatment, the median number of cisplatin courses was six for a dose intensity of 33 mg/m(2)/week. Doses to points A and B were 85 Gy (range 68-95) and 55 Gy (range 51-65), respectively. Chemoradiation was delivered in 44.6 (range 28-113) days. Complete response rates after all treatment were similar: 97% and 87% in the neoadjuvant and chemoradiation groups, respectively. At a median follow-up of 28 (range 2-33) and 24 (range 3-30) months, respectively, there were no differences in overall survival. To date, 15 and 13 patients in the neoadjuvant and chemoradiation groups, respectively, have died of disease (P = 0.8567). CONCLUSIONS: The results of this non-randomized comparison suggest that induction chemotherapy followed by surgery or chemoradiation is at least as effective in terms of response and survival as standard cisplatin-based chemoradiation. A randomized study is needed to confirm these findings.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/radioterapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma Adenoescamoso/tratamiento farmacológico , Carcinoma Adenoescamoso/patología , Carcinoma Adenoescamoso/radioterapia , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administración & dosificación , Terapia Combinada , Desoxicitidina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Tasa de Supervivencia , Resultado del Tratamiento , Gemcitabina
5.
Med Microbiol Immunol ; 189(3): 133-6, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11388610

RESUMEN

The stimulatory effect of lipopolysaccharide (LPS) on human macrophages was found to be neutralized by the detergent octylglucoside (OG). Both macrophage stimulation and reactivity in a limulus amebocyte lysate test were suppressed by suspension of LPS in OG at concentrations between 0.25 and 2.5 mM, whereas other stimulatory lipopeptides and lipid containing stimulants were unaffected by OG. LPS at concentrations causing maximal stimulation of macrophages could be completely neutralized by non-toxic concentrations of OG. In addition, it was found that the neutralization in complex mixtures of macromolecules, such as bacterial cell lysate, was specific for LPS and that the stimulatory activity of the other substances in the mixture was not affected by the OG.


Asunto(s)
Detergentes/farmacología , Glucósidos/farmacología , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Adhesinas Bacterianas/inmunología , Adhesinas Bacterianas/farmacología , Células Cultivadas , Escherichia coli , Humanos , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/farmacología , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Ácidos Teicoicos/inmunología , Ácidos Teicoicos/farmacología
6.
Ann Oncol ; 12(4): 541-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11398890

RESUMEN

BACKGROUND: Cisplatin-based chemoradiation for locally advanced cervical carcinoma is now the standard of care for most patients with cervical carcinoma. However, induction chemotherapy followed by surgery, particularly with newer agents or combinations remains to be explored. This study was undertaken to evaluate the antitumor activity and toxicity of gemcitabine in combination with cisplatin for untreated locally advanced cervical carcinoma. PATIENTS AND METHODS: Open-label, single center, phase II, non-randomized study of neoadjuvant gemcitabine plus cisplatin. Forty-one patients with histologic diagnosis of cervical carcinoma, with no previous treatment and staged as IB2 to IIIB, were treated with three 21-day courses of cisplatin 100 mg/m2 day I and gemcitabine 1000 mg/m2 days 1 and 8, followed by locoregional treatment with either surgery or concomitant chemoradiation. Response and toxicity were evaluated before each course and at the end of chemotherapy. RESULTS: All patients were evaluated for toxicity and 40 for response. The overall objective response rate was 95% (95% confidence interval (CI): 88%-100%) being complete in 3 patients (7.5%) and partial in 35 (87.5%). A complete pathological response was found in 6 (26%) of the 23 patients that underwent surgery. Granulocytopenia grades 3-4 occurred in 13.8% and 3.4% of the courses, respectively, whereas non-hematological toxicity was mild. CONCLUSIONS: Induction chemotherapy with the combination of gemcitabine and cisplatin is highly active for untreated cervical cancer patients and has an acceptable toxicity profile.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Adenoescamoso/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Carcinoma Adenoescamoso/mortalidad , Carcinoma Adenoescamoso/patología , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Cisplatino/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/patología , Gemcitabina
7.
Rev. chil. obstet. ginecol ; 62(2): 100-6, 1997. tab, graf
Artículo en Español | LILACS | ID: lil-206973

RESUMEN

Se revisan retrospectivamente 407 ciclos de inseminación intrauterina con semen del marido con el objeto de determinar factores pronósticos del procedimiento y el número de ciclos a realizar. Se encontró una diferencia significativa al comparar edad y años de infertilidad entre ciclos concepcionales y no concepcionales. Hubo un 3 por ciento de embarazos por ciclos con recuentos < 1 millón de espermatozoides móviles inseminados (EMI). El 97,7 por ciento de los embarazos se lograron en los primeros 4 ciclos, con una tasa acumulativa de 0,387. Se concluye que la IIU tiene mejor pronóstico en pacientes menores de 35 años, con una infertilidad menor de 5 años. El procedimiento no se justifica con recuentos menores a 1 milllón de EMI, y se sugiere no realizar más de 4 ciclos de tratamiento


Asunto(s)
Humanos , Femenino , Adulto , Embarazo , Infertilidad Femenina/terapia , Inseminación Artificial Homóloga/métodos , Pronóstico , Semen , Clomifeno/uso terapéutico , Inducción de la Ovulación/métodos , Menotropinas/uso terapéutico , Pronóstico
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