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1.
Hong Kong Med J ; 29(2): 121-131, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36822598

RESUMEN

INTRODUCTION: Worldwide, >130 babies have been born from ovarian tissue cryopreservation (OTC) and ovarian tissue transplantation (OTT). Ovarian tissue cryopreservation can improve quality of life among young female cancer survivors. Here, we assessed the feasibility of OTC and subsequent OTT in Hong Kong via xenografts in nude mice. METHODS: This pilot study was conducted in a university-affiliated tertiary hospital. Fifty-two ovarian tissues were collected from 12 patients aged 29 to 41 years during ovarian surgery, then engrafted into 34 nude mice. The efficacies of slow freezing and vitrification were directly compared. In Phase I, non-ovariectomised nude mice underwent ovarian tissue engraftment. In Phase II, ovariectomised nude mice underwent ovarian tissue engraftment, followed by gonadotrophin administration to promote folliculogenesis. Ovarian tissue viability was assessed by gross anatomical, histological, and immunohistochemical examinations before and after OTC. Follicular density and morphological integrity were also assessed. RESULTS: After OTC and OTT, grafted ovarian tissues remained viable in nude mice. Primordial follicles were observed in thawed and grafted ovarian tissues, indicating that the cryopreservation and transplantation protocols were both effective. The results were unaffected by gonadotrophin stimulation. CONCLUSION: This study demonstrated the feasibility of OTC in Hong Kong as well as primordial follicle viability after OTC and OTT in nude mice. Ovarian tissue cryopreservation is ideal for patients who cannot undergo the ovarian stimulation necessary for oocyte or embryo freezing as well as prepubertal girls (all ineligible for oocyte freezing). Our findings support the clinical implementation of OTC and subsequent OTT in Hong Kong.


Asunto(s)
Preservación de la Fertilidad , Animales , Ratones , Femenino , Humanos , Ratones Desnudos , Preservación de la Fertilidad/métodos , Hong Kong , Proyectos Piloto , Calidad de Vida , Criopreservación/métodos
2.
Zhonghua Yi Xue Za Zhi ; 103(23): 1787-1792, 2023 Jun 20.
Artículo en Zh | MEDLINE | ID: mdl-37305939

RESUMEN

Objective: To explore the correlation between electrical impedance indicators and commonly used nutritional indicators in neurocritical care patients. Methods: A cross-sectional study was conducted to collect 58 neurocritical care patients in neurosurgery Department of Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from June to September 2022. Bioelectrical impedance tests were performed after surgery or one week after injury, and nutrition-related biochemical indicators of the patients were collected on the same day, including nutritional status related indicators, inflammation related indicators, anemia related indicators and blood lipid related indicators. The patients were assessed with acute physiology and chronic health evaluation (APACHE) Ⅱ score and sequential organ failure assessment (SOFA) score. Based on the results obtained, the patients were assessed with nutritional score and spearman correlation analysis. The correlations of electrical impedance with nutrition related indicators and nutrition risk related indicators were analyzed. The prediction model of nutritional status was constructed by multi-factor binary logistic regression. Stepwise regression was used to screen electrical impedance indicators related to nutritional status. The receiver operating characteristic (ROC) curve was plotted and the area under the curve (AUC) was calculated to evaluate the predictive ability of the nutritional status prediction model. Results: A total of 58 patients were collected, including 33 males and 25 females, and aged 72.0 (59.0, 81.8) years. Extracellular water (ECW) was positively correlated with interleukin 6 (r=0.529, P<0.001). The edema index [ECW/total body water (TBW)] was negatively correlated with albumin (r=-0.700, P<0.001), hematocrit (r=-0.641, P<0.001) and hemoglobin (r=-0.667, P<0.001). The phase angle was positively correlated with albumin (rRA=0.667, rLA=0.649, rRL=0.669, rLL=0.685, all P<0.001), hematocrit (rRA=0.600, rLA=0.604, rTR=0.565, rRL=0.529, rLL=0.602, all P<0.001) and hemoglobin (rRA=0.626, rLA=0.635, rTR=0.594, rRL=0.624, rLL=0.631, all P<0.001). By stepwise regression screening of predictive factors for nutritional status and incorporating age, gender and white blood cells as confounding factors into the model, the final model was obtained as follows: nutritional status=-0.01×age+1.22×gender-0.12×white blood cells+202.20×ECW/TBW+0.5 torso phase angle -82.16 [The OR value of ECW/TBW: 20.8 (95%CI: 3.7-117.1), P<0.001], with the AUC of 0.921. Conclusion: Bioelectrical impedance indicators have good correlations with commonly used clinical nutritional indicators, and can provide a new method for nutritional evaluation of neurocritical care patients.


Asunto(s)
Albúminas , Estado Nutricional , Femenino , Masculino , Humanos , Impedancia Eléctrica , Estudios Transversales , China
3.
Zhonghua Wai Ke Za Zhi ; 61(1): 81-85, 2023 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-36603888

RESUMEN

Isolated superior mesenteric artery dissection (ISMAD) has attracted more and more clinicians' attention in recent years. Patients onset of ISMAD often present with abdominal pain. The misdiagnosis or miss diagnosis is common because of the non-specific symptoms and signs, which even can endanger lives in serious cases. Imaging classification is of great significance for diagnosis and treatment of ISMAD. The Sakamoto classification and the Yun classification are two classical classified methods. However, with the further study of ISMAD, various new classifications emerge. Conservative treatment was once considered as the preferred. As the rapid development of endovascular therapy and the great progress of new devices, stenting therapy can significantly improve symptoms and achieve satisfactory long-term effects, and be even expected to become the preferred method for clinical therapy of ISMAD. However, the long-term effects of endovascular therapy still need a large number of follow-up data, and complications after stent implantation can't be ignored.


Asunto(s)
Disección Aórtica , Procedimientos Endovasculares , Humanos , Arteria Mesentérica Superior , Resultado del Tratamiento , Tomografía Computarizada por Rayos X , Disección Aórtica/terapia , Stents , Estudios Retrospectivos
4.
BMC Gastroenterol ; 22(1): 160, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365084

RESUMEN

BACKGROUND: Non-traumatic hemoperitoneum was a rare event with the risk of sudden death. Spontaneous rupture of hepatocellular carcinoma is the most intuitive diagnosis when hemoperitoneum occurs in cirrhotic patients who are not regularly followed up. However, other etiologies of hemoperitoneum, such as intra-abdominal varix rupture, should be kept in mind. CASE PRESENTATION: A 44-year-old man with alcoholic liver cirrhosis, Child-Pugh B was sent to our emergency department (ED) because of recurrent abdominal pain and hypovolemic shock. He had similar symptoms one month ago and was diagnosed as hepatocellular carcinoma (HCC) rupture with hemoperitoneum, therefore he underwent trans-arterial embolization (TAE). However, the follow-up magnetic resonance imaging (MRI) showed less possibility of hepatocellular carcinoma. Contrast enhanced abdominal computed tomography (CT) showed possible umbilical vein contrast agent extravasation. Exploratory laparotomy confirmed the diagnosis of rupture umbilical varix with hemoperitoneum. CONCLUSION: Although umbilical varix rupture is a rare cause of hemoperitoneum, it should be kept in mind in cirrhotic patients with unexplained hemoperitoneum.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Várices , Adulto , Carcinoma Hepatocelular/complicaciones , Hemoperitoneo/diagnóstico por imagen , Hemoperitoneo/etiología , Humanos , Neoplasias Hepáticas/complicaciones , Masculino , Rotura Espontánea/complicaciones , Rotura Espontánea/diagnóstico por imagen , Várices/complicaciones , Várices/diagnóstico por imagen
5.
Ultrasound Obstet Gynecol ; 60(3): 425-427, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35653222

RESUMEN

Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies have been found in breast milk following both natural SARS-CoV-2 infection and coronavirus disease 2019 (COVID-19) vaccination. This was a prospective study to evaluate the temporal changes in amount and neutralization capacity of anti-SARS-CoV-2 antibodies in breast milk stimulated by natural infection and by vaccination. Serial breast milk samples were collected from postnatal women who were recruited through convenience sampling. We found a rapid increase in neutralizing SARS-CoV-2-specific antibodies in breast milk from both study groups. Amongst the infection group, the median immunoglobulin A (IgA) level was 16.99 (range, 0-86.56) ng/mL and median binding capacity was 33.65% (range, 0-67.65%), while in the vaccination group these were 30.80 (range, 0-77.40) ng/mL and 23.80% (range, 0-42.80%), respectively. In both groups, both binding capacity and IgA levels decreased progressively over time after peaking. Neutralizing activity had become undetectable by about 150 days after the first dose of the vaccine, but a vaccine booster dose restored secretion of neutralizing IgA, albeit with different levels of response in different individuals. This highlights the importance of the vaccine booster dose in sustaining neutralizing antibody levels in breast milk, which may potentially provide protection for very young children, who cannot receive the COVID-19 vaccine. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Anticuerpos Antivirales , COVID-19/prevención & control , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina A , Leche Humana , Estudios Prospectivos , SARS-CoV-2 , Vacunación
6.
Ultrasound Obstet Gynecol ; 57(6): 974-978, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33798280

RESUMEN

OBJECTIVE: To investigate the association of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load and infection-to-delivery interval with maternal and cord serum concentrations of anti-SARS-CoV-2 immunoglobulin G (IgG) antibodies and transplacental transfer ratio in pregnant women with active or recovered SARS-CoV-2 infection. METHODS: This was a prospective case series of consecutive pregnant women with laboratory-confirmed SARS-CoV-2 infection between 27 March 2020 and 24 January 2021. We collected information regarding deep throat saliva or nasopharyngeal swab (NPS) reverse transcription polymerase chain reaction (RT-PCR) test results, serial cycle threshold (Ct) values at and after diagnosis, demographic, clinical and outcome data, and neonatal NPS RT-PCR results. Qualitative and quantitative analysis of IgG and immunoglobulin M (IgM) antibodies against SARS-CoV-2 was performed in maternal and cord blood serum samples obtained at delivery. Correlation of maternal Ct values, infection-to-delivery interval, infection duration and viral load area under the curve (AUC) with gestational age (GA) at diagnosis, maternal and cord serum IgG concentrations and transplacental transfer ratio of IgG were evaluated using Pearson's correlation. RESULTS: Twenty pregnant women who consented to participate and who had delivered their babies by 31 January 2021 were included in the study, comprising 14 who had recovered from coronavirus disease 2019 (COVID-19) and six with active infection at delivery. The median GA at clinical manifestation was 32.7 (range, 11.9-39.4) weeks. The median infection-to-delivery interval and infection duration were 41.5 (range, 2-187) days and 10.0 (range, 1-48) days, respectively. The median GA at delivery was 39.1 (range, 32.4-40.7) weeks and the median seroconversion interval was 14 (range, 1-19) days. Of 13 neonates born to seropositive mothers with recovered infection at delivery, 12 tested positive for anti-SARS-CoV-2 IgG. All neonatal NPS samples were negative for SARS-CoV-2 and all cord sera tested negative for IgM. The median transplacental transfer ratio of IgG was 1.3 (interquartile range, 0.9-1.6). There was a negative correlation between infection-to-delivery interval and anti-SARS-CoV-2 IgG concentrations in maternal (r = -0.6693, P = 0.0087) and cord (r = -0.6554, P = 0.0068) serum and a positive correlation between IgG concentration in maternal serum and viral load AUC (r = 0.5109, P = 0.0310). A negative correlation was observed between transfer ratio and viral load AUC (r = -0.4757, P = 0.0409). CONCLUSIONS: In pregnant women who have recovered from COVID-19, anti-SARS-CoV-2 IgG concentrations at delivery increased with increasing viral load during infection and decreased with increasing infection-to-delivery interval. The median transplacental transfer ratio of IgG was 1.3 and it decreased with increasing viral load during infection. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Inmunidad Materno-Adquirida/inmunología , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Complicaciones Infecciosas del Embarazo/inmunología , Carga Viral/inmunología , Adulto , Prueba de Ácido Nucleico para COVID-19 , Prueba Serológica para COVID-19 , Estudios de Cohortes , Femenino , Sangre Fetal/inmunología , Edad Gestacional , Humanos , Embarazo , Estudios Prospectivos , SARS-CoV-2/inmunología , Factores de Tiempo
7.
Zhonghua Zhong Liu Za Zhi ; 43(7): 781-786, 2021 Jul 23.
Artículo en Zh | MEDLINE | ID: mdl-34289573

RESUMEN

Objective: To investigate the pathological features of gastric tumor originated from the fundic gland, including oxyntic gland adenoma (OGA) and gastric adenocarcinoma of the fundic gland (GA-FG). Methods: A retrospective analysis of 2 cases of OGA and 2 cases of GA-FG admitted to our hospital from February 2019 to September 2019 was performed. The histological features were analyzed by immunohistochemical staining combined with endoscopic observation. Results: The four cases arose from the deep layer of the lamina propria mucosae and well differentiated. Two cases of OGA confined to the mucosa, including 1 case of irregular tubules showing low-degree dysplasia and another case of irregular branching and anastomosing tubules showing high-degree dysplasia. Two cases of GA-FG combined with submucosal invasion, showed irregular branching and anastomosing tubules and formed a so-called "endless glands" pattern. Atypia, helicobacter pylori (HP) infection, chronic gastritis, intestinal metaplasia, or gastric atrophy were not observed in the superficial epithelium covering the tumor extent. Two cases of OGA and 2 cases of GA-FG showed the same result of immunohistochemical staining: pepsinogen-1 was diffusely positive in the tumor tissues and indicated chief cell differentiation, while positive ATPase and PDGFRA-α indicated parietal cells differentiation. The expression of Syn were positive in all cases, while CD10, MUC2 and CD-X2 were negative. The upregulation of p53 protein or nuclear positivity of ß-catenin was not observed. The Ki-67 labeling index in the hot area was approximately 1-5%. Conclusions: GA-FG is a well-differentiated, low-grade malignant novel subtype of gastric cancer. The immunohistochemical markers and narrowband imaging combined with magnifying endoscopy (NBI-ME) enhance the diagnostic sensitivity. Whether Syn positive expression can be one of the diagnostic item needs to be further investigate. The process of tumorigenesis of GA-FG might be the transition from low-grade dysplasia to high-grade dysplasia of OGA and further to submucosal infiltration. However, the mechanism of GAFG was still unclear. Disregulation of the Shh and Wnt/ß-catenin signaling pathway might be associated with tumorigenesis of GA-FG. Endoscopic submucosal dissection (ESD) is often the preferred and curative treatment.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/cirugía , Fundus Gástrico , Mucosa Gástrica , Humanos , Estudios Retrospectivos , Neoplasias Gástricas/cirugía
8.
Zhonghua Yi Xue Za Zhi ; 101(40): 3351-3354, 2021 Nov 02.
Artículo en Zh | MEDLINE | ID: mdl-34758537

RESUMEN

The clinical data of two children with Imerslund-Gräsbeck syndrome (IGS) who were admitted to the First Affiliated Hospital of Zhengzhou University in August 2019 was analyzed retrospectively. The two cases were siblings, aged 8 years and 8 months and 6 years and 2 months, respectively. These two boys had megaloblastic anemia, low level of vitamin B12, hyperhomocysteinemia, accompanied by proteinuria and renal tubular injury, while they showed normal folate level and renal function. Blood tandem mass spectrometry and urine organic acid analysis suggested methylmalonic acidemia (MMA). The initial diagnosis was MMA with homocysteinemia. No known pathogenic gene mutation related to MMA was found by gene sequencing. Compound heterozygous variants of amnionless (AMN) gene were detected: c.43+5G>A and c.C717G. The corrected diagnosis was IGS. Both brothers were treated with long-term intramuscular injection of vitamin B12. After follow-up for one year, these two cases had no clinical symptoms, and their blood indicators remained normal, but proteinuria and renal tubular injury persisted. Blood tandem mass spectrometry and urine organic acid analysis alone may easily lead to misdiagnosis, but combined with genetic testing can improve the accuracy of diagnosis of IGS. Lifelong parenteral vitamin B12 replacement therapy can effectively reverse the clinical and biochemical results, but is uncertain in alleviating albuminuria and renal tubule injury. It's necessary to monitor the renal function regularly.


Asunto(s)
Anemia Megaloblástica , Deficiencia de Vitamina B 12 , Anemia Megaloblástica/genética , Niño , Humanos , Síndromes de Malabsorción , Masculino , Proteinuria , Estudios Retrospectivos , Hermanos , Vitamina B 12
9.
Appl Opt ; 59(4): 1028-1036, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32225239

RESUMEN

Isosbestic plasmonic nanostructures, which feature an invariance of optical absorption and heat generation upon varying the incident light polarization, have broad application in many fields such as nanochemistry, optical nanoantennas, and microbubble formation. In this study, we focus on the isosbestic optical absorption by metallic dimers and systematically investigate the coupling between two interacting particles by using both the superposition T-matrix method and dipole approximation model. We observe that the interparticle coupling effects on particle absorption can be both positive and negative, compared to an isolated particle. Meanwhile, the optical absorption properties of spheres with small size parameters can realize more flexible control through changing the sphere size, interparticle distance, and incident light wavelength. For illuminations with incident light propagating perpendicularly to the line joining the centers of the two spheres, isosbestic conditions will be satisfied as long as the absorption efficiencies for transverse and longitudinal illuminations are equal. For transverse illuminations along the dimer axis, the ratio of absorption efficiency of the two metallic spheres presents the fluctuation change with the interparticle distance. Owing to the strong interparticle coupling effects, it even leads to the absorption efficiency of the far sphere being higher than that of the near sphere. Our results are aimed at expanding our understanding of the interparticle electromagnetic coupling effects on isosbestic light absorption in plasmonic nanoparticle systems.

10.
Zhonghua Gan Zang Bing Za Zhi ; 28(2): 147-151, 2020 Feb 20.
Artículo en Zh | MEDLINE | ID: mdl-32164066

RESUMEN

Objective: To investigate the effect of knockdown of O-GlcNAc transferase (OGT) on hepatocyte fat synthesis. Methods: Liver cell line L02 were used to established the model of hepatic steatosis. The levels of OGT and O-GlcNAc protein were detected by Western blot. The OGT knockdown cell line of L02 cells was established, and its lipid formation ability was detected after induction of oleic acid (OA). Real-time quantitative PCR (qRT-PCR) and Western blot were used to detect mRNA and protein expression of enzymes related to fat synthesis. An independent sample t test was used. Results: Western blot showed that the expression of OGT and O-GlcNAc was increased in L02 cells after adipogenesis (P < 0.05). After shOGT lentivirus infects L02 cells, OGT mRNA levels were down-regulated (P < 0.01). Oil red O staining showed that the lipid in L02 shOGT cells decreased, qRT-PCR showed that the mRNA expressions of fat synthase (ACC1), (FASN) and (SCD1) were decreased, the difference was statistically significant (P < 0.05), protein Expression is consistent with mRNA expression. Conclusion: Knockdown of OGT can inhibit hepatocyte fat synthesis by reducing O-GlcNAc levels.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Hígado Graso , Hepatocitos/metabolismo , Histona Acetiltransferasas/metabolismo , Hialuronoglucosaminidasa/metabolismo , N-Acetilglucosaminiltransferasas/metabolismo , Línea Celular , Humanos
11.
J Lipid Res ; 60(5): 1043-1049, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30914501

RESUMEN

Endogenous synthesis of PUFAs is mediated by genes controlling fatty acid elongases 2 and 5 (ELOVL2 and ELOVL5) and by exogenous DHA intake. Associations between elongases and PUFA levels probably involve genetic variants of ELOVL and changes in DHA intake, but data about their combined effect on PUFA levels are sparse. We hypothesized that each factor would directly affect PUFAs and that interactions between haplotypes and DHA intake would influence PUFAs. We explored four levels of DHA intake in pregnant Chinese Han women and 10 SNPs in the ELOVL genes to determine associations with PUFAs in breast milk. The SNP rs3798713 and 3-SNP haplotype (rs2281591, rs12332786, and rs3798713) in ELOVL2 were associated with linoleic acid (LA) concentrations. However, carriers of the 3-SNP haplotype with higher DHA intake (second quartile: 14.58-43.15 mg/day) had higher concentrations of LA, arachidonic acid, EPA, and DHA compared with the interaction baseline. In ELOVL5, five SNPs (rs2294867, rs9357760, rs2397142, rs209512, and rs12207094) correlated with PUFA changes. Compared with those who had the 5-SNP haplotype C-A-C-G-A and low DHA intake (<14.58 mg/day), carriers with other haplotypes (A-A-C-A-A or C-A-C-A-A) and high DHA intake (≥118.82 mg/day) had increased EPA levels after adjustments for age and BMI. This study showed that maternal genetic variants in ELOVL2 and ELOVL5 were associated with PUFA levels in breast milk and that the combination of SNP haplotypes and higher DHA intake increased PUFA concentrations.


Asunto(s)
Ácidos Docosahexaenoicos/química , Elongasas de Ácidos Grasos/química , Ácidos Grasos Insaturados/análisis , Variación Genética , Leche Humana/química , Adulto , China , Dieta , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Elongasas de Ácidos Grasos/genética , Femenino , Variación Genética/genética , Genotipo , Voluntarios Sanos , Humanos , Polimorfismo de Nucleótido Simple/genética , Embarazo , Encuestas y Cuestionarios , Adulto Joven
12.
BJOG ; 126(2): 271-279, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30106234

RESUMEN

OBJECTIVE: To ascertain whether stress biomarkers and psychological indices of stress may predict both conception and miscarriage rates in women undergoing in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI). DESIGN: Prospective observational study. SETTING: A university-affiliated tertiary hospital. POPULATION: Infertile women who were undergoing fresh or frozen IVF/ICSI cycles. METHODS: Women were recruited to (1) complete validated psychological questionnaires (visual analogue scale of stress, state-trait anxiety inventory, perceived stress scale, fertility problem inventory, Beck depression inventory, and general health questionnaire), at the time of embryo transfer (ET) and pregnancy testing (PT), and (2) provide saliva samples for α-amylase (sAA) measurement before and after ET and at PT. MAIN OUTCOME MEASURES: Women were grouped according to subsequent reproductive outcome; scores/levels of all tests were then compared between groups at each time-point. RESULTS: In all, 197 women completed the study, of which 92 conceived and 28 miscarried. The level of psychological stress, as measured by questionnaires, was highest at the time of PT, whereas the level of biological stress as measured by sAA level (IU/l) post-ET (1.8 × 105  ± 1.5 × 105 ) was significantly (P < 0.001) higher than pre-ET (1.2 × 105  ± 1.0 × 105 ) and at PT (1.0 × 105  ± 1.1 × 105 ). However, there was no difference in psychological scoring and in sAA levels between women who did or did not conceive and who had miscarried or had an ongoing pregnancy. CONCLUSIONS: The level of sAA is highest following ET, whereas psychological stress is highest at PT. However, neither stress level appeared to be of prognostic value in predicting conception or miscarriage. TWEETABLE ABSTRACT: Stress level fluctuated at different time-points, but it did not predict conception or miscarriage.


Asunto(s)
Transferencia de Embrión/psicología , Estrés Fisiológico , Estrés Psicológico/psicología , Aborto Espontáneo/epidemiología , Adulto , Biomarcadores/análisis , Femenino , Fertilización In Vitro/psicología , Humanos , Infertilidad Femenina/psicología , Infertilidad Femenina/terapia , Embarazo , Índice de Embarazo , Pruebas de Embarazo/psicología , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , alfa-Amilasas Salivales/análisis , Resultado del Tratamiento
13.
Appl Opt ; 58(26): 7157-7164, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31503989

RESUMEN

This paper focuses on polarized radiative transfer in a thin layer composed of titanium dioxide particles while considering the effect of host medium absorption on particle scattering. The single-scattering properties of particles in an absorbing medium are calculated using the modified Lorenz-Mie program recently developed based on the first-principles theory of electromagnetic scattering, and the vector radiative transfer equation is solved by using the spectral element method. The relative errors of Stokes parameters caused by using the conventional Lorenz-Mie theory are systemically investigated. The results show that neglecting the effect of host medium absorption on particle scattering has a more significant impact on the radiation intensity than the polarization components in most cases. Meanwhile, the relative errors of Stokes parameters induced by using the conventional Lorenz-Mie theory obviously increase with the increase of the host medium absorption index and particle size parameter. Due to the larger scattering coefficients and scattering albedos (i.e., for the case of particle size parameter x=10.0 in this study), the relative errors of Stokes parameters of monodisperse particles are obviously larger than those of polydisperse particles. Moreover, it is found that the relative errors of the Stokes parameters change nonlinearly with the particle volume fraction, especially for large size particles.

14.
Appl Opt ; 58(27): 7336-7345, 2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31674380

RESUMEN

Light scattering and radiative transfer in optically soft particle systems are important problems in many fields of natural sciences and engineering, such as biology, ocean optics, atmospheric science, solar energy utilization, and so on. Due to the effects of particle agglomeration and dependent scattering, the radiative transfer problem will become more complex with the increase of particle volume fraction. In this study, the scattering properties and radiative transfer characteristics of densely packed optically soft particle systems, with consideration of the effects of dependent scattering and particle agglomeration, are investigated. The dependent scattering properties of densely packed silicon-dioxide spherical particles embedded in water are calculated by using the Lorenz-Mie theory and Percus-Yevick sticky hard-sphere model. The directional-hemispherical reflectance of the dispersed plane-parallel layer is obtained by using the Monte Carlo method. The results show that dependent scattering and particle agglomeration have significant influence on the scattering properties of particles. With the increase of particle agglomeration degree, the scattering coefficients and asymmetry factors of the particles increase obviously, which can be even larger than the results for independent scattering under certain circumstances. Due to the combined interaction of multiple scattering, dependent scattering, and particle agglomeration, for different size particles, the variation tendency of the hemispherical reflectance is obviously different with increasing particle agglomeration degree.

16.
Zhonghua Yi Xue Za Zhi ; 99(5): 338-342, 2019 Jan 29.
Artículo en Zh | MEDLINE | ID: mdl-30772973

RESUMEN

Objective: To investigate the value of multiple parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and three-dimensional arterial spin labeling (3D-ASL) in Ki-67 labeling index (Ki-67 LI) and grading of human brain gliomas. Methods: From December 2015 to May 2018, 45 patients of gliomas confirmed by surgical pathology in Li Huili Hospital, Ningbo Medical Center were divided into low-grade group (20 cases of WHO grade Ⅱ) and high-grade group (12 cases of WHO grade Ⅲ, 13 cases of WHO grade Ⅳ), and the Ki-67 LI of glioma was obtained by immunohistochemistry. All patients, 24 males and 21 females, aged 25-83 years, mean(53±12)years, underwent conventional magnetic resonance imaging (MRI), IVIM-DWI and 3D-ASL before operation, then measured the true water diffusion coefficient (D), microcirculation perfusion coefficient (D(*)), perfusion fraction (f) and cerebral blood flow (CBF) in the tumor solid area and the contralateral normal white matter area. Those parameters and the Ki-67 LI were compared between the low-and high-grade groups with Mann-Whitney U test. Spearman's correlation was used to analyze the correlation between the quantitative parameters and Ki-67 LI. The ROC curve was used to assess the diagnostic efficacy of parameters in the grading assessment of brain gliomas. Results: The D(0.791×10(-3)mm(2)/s) and f (0.261) of the high-grade group were lower than those of the low-grade group, whereas D(*) (4.153×10(-3) mm(2)/s), CBF(102.027 ml·min(-1)·100 g(-1)) and Ki-67 LI (0.25) were higher (P<0.05). There was a moderate negative correlation between D, f and Ki-67 LI(r=-0.513,-0.457, all P<0.05). There was no significant correlation between D(*) and Ki-67 LI (P=0.571). The area under the curve (AUC) for identifying high-and low-grade gliomas by D, D(*), f and CBF values was 0.965, 0.745, 0.842, and 0.830 respectively (all P<0.05). Conclusion: D and f can be used for quantitative prediction of Ki-67 LI. IVIM-DWI and 3D-ASL are helpful in the grading assessment of gliomas, and the diagnostic efficiency of D is the highest.


Asunto(s)
Neoplasias Encefálicas , Glioma , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Movimiento (Física) , Clasificación del Tumor , Marcadores de Spin
17.
Int J Obes (Lond) ; 42(4): 679-685, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29158542

RESUMEN

BACKGROUND/OBJECTIVE: The term macrosomia is used to describe neonates with a birth weight of 4000 g or more. Macrosomia is a potential risk factor for obesity and metabolic syndromes in postnatal and adult life, yet little is known about its associations with metabolic difference in the early age. We performed metabolic profiling of umbilical cord blood to discover differential metabolites of macrosomia. METHODS: We conducted a case-control study of full-term singletons with normal maternal glucose tolerance [50 cases (macrosomia, birth weight ⩾4000 g); 50 controls (normal weight, birth weight 2500-3999 g)]. Metabolites in umbilical cord blood were detected using an untargeted metabolomic approach based on gas chromatography/mass spectrometry. We performed logistic regression to evaluate the associations between metabolites and macrosomia. We also performed pathway analysis based on KEGG and MBRole. RESULTS: Compared with controls, the macrosomia cases had a greater male proportion, gestational age, paternal body mass index (BMI) and maternal pre-pregnancy BMI. Forty-two metabolites differed between the cases and controls. After multivariable adjustment, 2-methylfumarate [adjusted odds ratio (AOR)=1.232, 95% confidence interval (CI): 1.102-1.376], uracil (AOR=38.494, 95% CI: 5.635-262.951), elaidic acid (AOR=0.834, 95% CI: 0.761-0.915), ribose (AOR=0.089, 95% CI: 0.021-0.378), lactulose (AOR=0.815, 95% CI: 0.743-0.894) and 4-aminobutyric acid (AOR=0.835, 95% CI: 0.764-0.912) remained significantly associated with macrosomia. Pyrimidine metabolism and pentose and glucuronate interconversions were the two top-ranking pathways enriched with those metabolites (-log P-value=3.49 and 2.47, respectively). CONCLUSION: Levels of 2-methylfumarate, uracil, ribose, elaidic acid, lactulose and 4-aminobutyric acid were associated with the incidence of macrosomia. The alteration of pathways involving those factors might be linked with the incidence of macrosomia and relevant metabolic syndromes later in life, and further studies are needed to confirm it and verify the mechanisms.


Asunto(s)
Peso al Nacer/fisiología , Macrosomía Fetal/sangre , Macrosomía Fetal/epidemiología , Metaboloma/fisiología , Adulto , Biomarcadores/sangre , Biomarcadores/metabolismo , Estudios de Casos y Controles , Femenino , Sangre Fetal/química , Humanos , Recién Nacido , Masculino , Redes y Vías Metabólicas , Metabolómica , Análisis Multivariante , Embarazo , Adulto Joven
18.
Br J Surg ; 105(2): e142-e149, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29341160

RESUMEN

BACKGROUND: A histological, tumour-free surgical margin does not guarantee recurrence-free survival in patients with cancer. This study investigated the association between microsatellite alteration in tumour-free surgical margins and local recurrence in patients with oral cavity squamous cell carcinoma. METHODS: Patients with histologically confirmed oral cavity squamous cell carcinoma were enrolled in this prospective study. Cancerous specimens, corresponding surgical margins and peripheral blood were obtained. Microsatellite alteration was investigated using six dinucleotide microsatellite markers. All samples were amplified by PCR, followed by automatic fragment analysis. RESULTS: Microsatellite alteration was identified in 100 specimens (69·0 per cent) from 145 patients. Among them, 85 specimens carried loss of heterozygosity, whereas 55 had microsatellite instability (MSI). Patients with MSI at the surgical margin had a higher risk of local recurrence on multivariable analysis (odds ratio 7·17, 95 per cent c.i. 3·49 to 14·73). CONCLUSION: Molecular assessment of surgical margins can help identify patients at risk of local recurrence.


Asunto(s)
Pruebas Genéticas/métodos , Inestabilidad de Microsatélites , Neoplasias de la Boca/genética , Recurrencia Local de Neoplasia/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Adulto , Anciano , Femenino , Humanos , Pérdida de Heterocigocidad , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Boca/patología , Neoplasias de la Boca/cirugía , Estudios Prospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía
19.
Nature ; 484(7395): 489-92, 2012 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-22538611

RESUMEN

The presence of long-range quantum spin correlations underlies a variety of physical phenomena in condensed-matter systems, potentially including high-temperature superconductivity. However, many properties of exotic, strongly correlated spin systems, such as spin liquids, have proved difficult to study, in part because calculations involving N-body entanglement become intractable for as few as N ≈ 30 particles. Feynman predicted that a quantum simulator--a special-purpose 'analogue' processor built using quantum bits (qubits)--would be inherently suited to solving such problems. In the context of quantum magnetism, a number of experiments have demonstrated the feasibility of this approach, but simulations allowing controlled, tunable interactions between spins localized on two- or three-dimensional lattices of more than a few tens of qubits have yet to be demonstrated, in part because of the technical challenge of realizing large-scale qubit arrays. Here we demonstrate a variable-range Ising-type spin-spin interaction, J(i,j), on a naturally occurring, two-dimensional triangular crystal lattice of hundreds of spin-half particles (beryllium ions stored in a Penning trap). This is a computationally relevant scale more than an order of magnitude larger than previous experiments. We show that a spin-dependent optical dipole force can produce an antiferromagnetic interaction J(i,j) proportional variant d(-a)(i,j), where 0 ≤ a ≤ 3 and d(i,j) is the distance between spin pairs. These power laws correspond physically to infinite-range (a = 0), Coulomb-like (a = 1), monopole-dipole (a = 2) and dipole-dipole (a = 3) couplings. Experimentally, we demonstrate excellent agreement with a theory for 0.05 ≲ a ≲ 1.4. This demonstration, coupled with the high spin count, excellent quantum control and low technical complexity of the Penning trap, brings within reach the simulation of otherwise computationally intractable problems in quantum magnetism.

20.
Appl Opt ; 57(5): 1260-1266, 2018 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-29469874

RESUMEN

The optical constants of five highly transparent substrates (polycrystalline BaF2, CaF2, MgF2, ZnSe, and ZnS) were experimentally determined based on a combined technique using both the double optical pathlength transmission method and the ellipsometry method within temperature range 20°C-350°C in the ultraviolet-infrared region (0.2-20 µm). The results show that the refractive index spectra of polycrystalline BaF2, CaF2, and MgF2 are similar, but differ from that of polycrystalline ZnSe and ZnS. The thermo-optic coefficient of these highly transparent substrates increases with increasing temperature. The absorption indices show a significant temperature-dependent behavior, which increases with increasing temperature from 20°C to 350°C over the transparent region. For the sake of application, the fitted formulas of the refractive index of the five highly transparent substrates as a function of wavelength and temperature are presented.

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