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1.
Nucleic Acids Res ; 51(4): 1583-1599, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36727438

RESUMEN

Inefficient endosomal escape remains the primary barrier to the broad application of oligonucleotide therapeutics. Liver uptake after systemic administration is sufficiently robust that a therapeutic effect can be achieved but targeting extrahepatic tissues remains challenging. Prior attempts to improve oligonucleotide activity using small molecules that increase the leakiness of endosomes have failed due to unacceptable toxicity. Here, we show that the well-tolerated and orally bioavailable synthetic sphingolipid analog, SH-BC-893, increases the activity of antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs) up to 200-fold in vitro without permeabilizing endosomes. SH-BC-893 treatment trapped endocytosed oligonucleotides within extra-lysosomal compartments thought to be more permeable due to frequent membrane fission and fusion events. Simultaneous disruption of ARF6-dependent endocytic recycling and PIKfyve-dependent lysosomal fusion was necessary and sufficient for SH-BC-893 to increase non-lysosomal oligonucleotide levels and enhance their activity. In mice, oral administration of SH-BC-893 increased ASO potency in the liver by 15-fold without toxicity. More importantly, SH-BC-893 enabled target RNA knockdown in the CNS and lungs of mice treated subcutaneously with cholesterol-functionalized duplexed oligonucleotides or unmodified ASOs, respectively. Together, these results establish the feasibility of using a small molecule that disrupts endolysosomal trafficking to improve the activity of oligonucleotides in extrahepatic tissues.


Asunto(s)
Endosomas , Oligonucleótidos , Animales , Ratones , Oligonucleótidos/metabolismo , Endosomas/genética , Endocitosis/fisiología , Transporte Biológico , Oligonucleótidos Antisentido/genética , ARN Interferente Pequeño/genética
2.
J Struct Biol ; 215(1): 107911, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36343843

RESUMEN

Cryo-electron tomography (cryo-ET) and subtomogram averaging (STA) can resolve protein complexes at near atomic resolution, and when combined with focused ion beam (FIB) milling, macromolecules can be observed within their native context. Unlike single particle acquisition (SPA), cryo-ET can be slow, which may reduce overall project throughput. We here propose a fast, multi-position tomographic acquisition scheme based on beam-tilt corrected beam-shift imaging along the tilt axis, which yields sub-nanometer in situ STA averages.


Asunto(s)
Tomografía con Microscopio Electrónico , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía por Crioelectrón/métodos , Tomografía con Microscopio Electrónico/métodos , Sustancias Macromoleculares
3.
Nucleic Acids Res ; 49(4): 1828-1839, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33544849

RESUMEN

We recently showed that site-specific incorporation of 2'-modifications or neutral linkages in the oligo-deoxynucleotide gap region of toxic phosphorothioate (PS) gapmer ASOs can enhance therapeutic index and safety. In this manuscript, we determined if introducing substitution at the 5'-position of deoxynucleotide monomers in the gap can also enhance therapeutic index. Introducing R- or S-configured 5'-Me DNA at positions 3 and 4 in the oligodeoxynucleotide gap enhanced the therapeutic profile of the modified ASOs suggesting a different positional preference as compared to the 2'-OMe gap modification strategy. The generality of these observations was demonstrated by evaluating R-5'-Me and R-5'-Ethyl DNA modifications in multiple ASOs targeting HDAC2, FXI and Dynamin2 mRNA in the liver. The current work adds to a growing body of evidence that small structural changes can modulate the therapeutic properties of PS ASOs and ushers a new era of chemical optimization with a focus on enhancing the therapeutic profile as opposed to nuclease stability, RNA-affinity and pharmacokinetic properties. The 5'-methyl DNA modified ASOs exhibited excellent safety and antisense activity in mice highlighting the therapeutic potential of this class of nucleic acid analogs for next generation ASO designs.


Asunto(s)
ADN/química , Oligonucleótidos Antisentido/química , Animales , Glucosa/análogos & derivados , Glucosa/química , Células HeLa , Humanos , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Oligonucleótidos Antisentido/uso terapéutico , Oligonucleótidos Antisentido/toxicidad , Compuestos Organofosforados/síntesis química , Ribonucleasa H
4.
Nucleic Acids Res ; 49(16): 9026-9041, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34417625

RESUMEN

The PS modification enhances the nuclease stability and protein binding properties of gapmer antisense oligonucleotides (ASOs) and is one of very few modifications that support RNaseH1 activity. We evaluated the effect of introducing stereorandom and chiral mesyl-phosphoramidate (MsPA) linkages in the DNA gap and flanks of gapmer PS ASOs and characterized the effect of these linkages on RNA-binding, nuclease stability, protein binding, pro-inflammatory profile, antisense activity and toxicity in cells and in mice. We show that all PS linkages in a gapmer ASO can be replaced with MsPA without compromising chemical stability and RNA binding affinity but these designs reduced activity. However, replacing up to 5 PS in the gap with MsPA was well tolerated and replacing specific PS linkages at appropriate locations was able to greatly reduce both immune stimulation and cytotoxicity. The improved nuclease stability of MsPA over PS translated to significant improvement in the duration of ASO action in mice which was comparable to that of enhanced stabilized siRNA designs. Our work highlights the combination of PS and MsPA linkages as a next generation chemical platform for identifying ASO drugs with improved potency and therapeutic index, reduced pro-inflammatory effects and extended duration of effect.


Asunto(s)
Oligonucleótidos Antisentido/síntesis química , Índice Terapéutico de los Medicamentos , Animales , Células HEK293 , Células HeLa , Humanos , Hígado/metabolismo , Masculino , Mesilatos/química , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Oligonucleótidos Antisentido/farmacocinética , Oligonucleótidos Antisentido/toxicidad , Fosforamidas/química , Unión Proteica , Distribución Tisular
5.
Hong Kong Med J ; 29(4): 287-294, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37409372

RESUMEN

INTRODUCTION: This study investigated the awareness, perceptions, and acceptance of human papillomavirus (HPV) vaccination for children among parents in Hong Kong. It also explored factors associated with, and differences in, vaccine acceptance and hesitancy between parents of girls and boys. METHODS: Parents of boys or girls in Primary 5 to 6 were invited to participate in an online survey through an established health and lifestyle e-platform. RESULTS: Overall, 851 parents completed the survey: 419 (49.2%) had daughters, 348 (40.9%) had sons, and 84 (9.9%) had children of both genders. Parents who enrolled their children into the Childhood Immunisation Programme were more likely to accept HPV vaccination (79.7% vs 33.7%, odds ratio [OR]=7.70; 95% confidence interval [CI]=5.39-11.01; P<0.001); parents of girls were more likely to accept than parents of boys (86.0% vs 71.8%, OR=2.40; 95% CI=1.67-3.46; P<0.001). Among parents of girls and boys, the main reasons for HPV vaccination acceptance were prevention of cancers (girls: 68.8% and boys: 68.7%), prevention of sexually transmitted diseases (girls: 67.3% and boys: 68.3%), and optimal timing before initiation of sexual activity (girls: 62.8% and boys: 59.8%). Vaccine hesitancy was mainly associated with concerns about serious side-effects (girls: 66.7% and boys: 68.0%) and the belief that their children were too young (girls: 60.0% and boys: 54.0%). CONCLUSION: Parents in Hong Kong are hesitant about HPV vaccination for their sons. This barrier could be removed by providing information to correct vaccine safety misconceptions and offering a gender-neutral vaccination programme through the school-based Childhood Immunisation Programme.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Niño , Humanos , Masculino , Femenino , Hong Kong , Infecciones por Papillomavirus/prevención & control , Virus del Papiloma Humano , Aceptación de la Atención de Salud , Conocimientos, Actitudes y Práctica en Salud , Padres , Vacunación
6.
Can Assoc Radiol J ; 74(2): 288-297, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36223428

RESUMEN

Introduction: Prior studies on Canadian physicians' income have demonstrated a gender pay gap (GPG); however, there is a paucity of data in the Radiology specialty. A cross-sectional study was conducted to determine if practicing Canadian radiologists' self-reported income is related to gender, controlling for demographic and work variables. Methods: English and French online surveys were distributed by email and social media to radiologists and trainees (May-July 2021). The association between Gender (controlling for Ethnicity variables, Region, having Children, Full-/Part-Time work, and Academic position) and Self-Reported Income was examined using chi-square tests. Pearson correlations examined relationships between opinion variables. Analyses were conducted using SPSS V28.0. A priori significance was P < .05. Study had ethics approval. Results: Four hundred and fifty-four practicing Canadian radiologists responded. Majority were women (51.2%, n = 227), a non-visible Minority (71.7%, n = 317), and from Western Provinces (67.8%, n = 308). Significant relationship was established between Self-Reported Income and Gender (χ2 = 10.44, df = 2, P < .05). More men (70.6%, n = 120) than women (56.4%, n = 110), reported income "greater than $500 000"; fewer men (20.6%, n = 35) than women (35.9%, n = 70) reported "$300 000-$500 000"; a similar percent of men (8.8%, n = 15) and women (7.7%, n = 15) reported "less than $300 000." No relationship was found between self-reported income and gender for ethnicity variables, those without children, part-time, or non-academic radiologists. The opinion "Addressing the GPG is important" correlated to "Canadian Association of Radiologists should collect demographic data" (r = 0.63). Responses were low for ethnic minorities and non-western provinces. Conclusion: Our results suggest a GPG exists in Canadian radiology and is an important first step for future studies.


Asunto(s)
Radiología , Niño , Humanos , Masculino , Femenino , Canadá , Estudios Transversales , Radiografía , Radiólogos
7.
Zhonghua Yi Xue Za Zhi ; 103(29): 2258-2265, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37544763

RESUMEN

Objective: To analyze the diagnostic and prognostic values of flow cytometry (FC) in diffuse large B cell lymphoma (DLBCL) with bone marrow involvement (BMI). Methods: The clinical data of 412 patients with newly diagnosed DLBCL, including 243 males and 169 females, aged 64 (28-92) years old, in the Department of Hematology at Peking University Third Hospital from December 2012 to June 2022 were retrospectively analyzed. All patients underwent bone marrow biopsy (BMB) and bone marrow FC. The patients with BMI by FC were further detected by fluorescence in situ hybridization (FISH) for gene analysis. The positive rates and consistency of BMI detected by BMB and FC were evaluated. According to the results of BMB and FC examinations, all patients were divided into four groups: the BMB+FC+group (115 cases), the BMB-FC+group (50 cases), the BMB+FC-group (8 cases, the results did not include in statistical analysis because of small sample size), and the BMB-FC-group (239 cases). The clinical features, treatment response rates, 5-year survival rates, and immunophenotype characteristics by FC in different groups were analyzed. Results: Among the 412 patients with DLBCL, the positivity rates of BMB and FC for BMI detection were 29.9% (123/412) and 40.0% (165/412), respectively. Good consistency between BMB and FC was found (Kappa=0.841, P=0.001). The numbers of extranodal involvement≥2, splenomegaly, huge mass, higher Ki-67 score, higher international prognostic index (IPI) score, thrombocytopenia, and elevated lactate dehydrogenase level were more prevalent in the BMB+FC+group than those in the BMB-FC+group and the BMB-FC-group (all P<0.05). The treatment response rate in BMB+FC+group was 63.5% (73/115), which was lower than those in BMB-FC+group (88.0%, 44/50, P=0.048) and BMB-FC-group (90.0%, 215/239, P=0.032), respectively. The 5-year overall survival rates in three groups were (53.6±9.7) %, (72.5±8.6) %, and (75.2±7.6) %, respectively, with a statistically significant difference (P=0.037). According to the FISH results of bone marrow, 102 cases were diagnosed as not otherwise specified (NOS), 48 cases were diagnosed as double hit lymphoma (DHL), and 15 cases were diagnosed as triple hit lymphoma (THL). Compared with NOS subtypes, the tumor cells in DHL or THL subtypes had higher proportion of increased side scatter (SSC), higher positive rates of CD10 expression, CD38 strong expression and CD56 expression, and lower proportion of surface immunoglobulin light chain restriction (all P<0.05). Conclusions: FC is well consistent with BMB in diagnosing DLBCL with BMI. Combined with FISH detection, FC can contribute to the auxiliary diagnosis and risk stratification for DHL and THL, and provide reference for the prognostic evaluation in DLBCL with BMI.


Asunto(s)
Médula Ósea , Linfoma de Células B Grandes Difuso , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico , Médula Ósea/patología , Citometría de Flujo , Masculino , Femenino , Estudios Retrospectivos , Hibridación Fluorescente in Situ
8.
Nucleic Acids Res ; 48(4): 1691-1700, 2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-31980820

RESUMEN

Therapeutic oligonucleotides are often modified using the phosphorothioate (PS) backbone modification which enhances stability from nuclease mediated degradation. However, substituting oxygen in the phosphodiester backbone with sulfur introduce chirality into the backbone such that a full PS 16-mer oligonucleotide is comprised of 215 distinct stereoisomers. As a result, the role of PS chirality on the performance of antisense oligonucleotides (ASOs) has been a subject of debate for over two decades. We carried out a systematic analysis to determine if controlling PS chirality in the DNA gap region can enhance the potency and safety of gapmer ASOs modified with high-affinity constrained Ethyl (cEt) nucleotides in the flanks. As part of this effort, we examined the effect of systematically controlling PS chirality on RNase H1 cleavage patterns, protein mislocalization phenotypes, activity and toxicity in cells and in mice. We found that while controlling PS chirality can dramatically modulate interactions with RNase H1 as evidenced by changes in RNA cleavage patterns, these were insufficient to improve the overall therapeutic profile. We also found that controlling PS chirality of only two PS linkages in the DNA gap was sufficient to modulate RNase H1 cleavage patterns and combining these designs with simple modifications such as 2'-OMe to the DNA gap resulted in dramatic improvements in therapeutic index. However, we were unable to demonstrate improved potency relative to the stereorandom parent ASO or improved safety over the 2'-OMe gap-modified stereorandom parent ASO. Overall, our work shows that while controlling PS chirality can modulate RNase H1 cleavage patterns, ASO sequence and design are the primary drivers which determine the pharmacological and toxicological properties of gapmer ASOs.


Asunto(s)
ADN/genética , Oligonucleótidos Antisentido/genética , Oligonucleótidos Fosforotioatos/genética , Ribonucleasa H/genética , Animales , ADN/química , Ratones , Oligonucleótidos Antisentido/química , Oligonucleótidos Fosforotioatos/química , Unión Proteica/genética , Ribonucleasa H/química
9.
Chem Soc Rev ; 50(4): 2444-2485, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33404560

RESUMEN

The development of reliable water oxidation catalysts (WOCs) is essential for implementing artificial photosynthesis on a large technological scale. WOC research has evolved into two major branches, namely molecular and heterogeneous catalysts. Manifold design principles and plenty of mechanistic insights have been developed in these individual fields after decades of investigations. Over the past years, a growing need for knowledge transfer between both sides has emerged in order to expedite the development and optimization of next-generation WOCs. In this review, we first provide selected recent highlights in the area of molecular WOCs with different nuclearities, together with current mechanistic insight. WOCs offering molecular integrity under operational conditions are ideal platforms for elucidating reaction mechanisms and well-defined structure-function correlations at the atomic level. Next, recent mechanistic advances and design strategies for heterogeneous WOCs are illustrated for representative examples, together with a discussion of their inherent limitations in mechanistic studies. Finally, illustrative cases of knowledge transfer between molecular and heterogeneous WOCs are discussed to highlight the advantages of combining the best of both catalyst types. For the sake of conciseness, this review focuses primarily on WOCs based on the first-row transition metals, which are attracting increasing attention for both fundamental studies and economic applications.

10.
Nucleic Acids Res ; 47(11): 5465-5479, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-31034558

RESUMEN

Phosphorothioate-modified antisense oligonucleotides (PS-ASOs) interact with a host of plasma, cell-surface and intracellular proteins which govern their therapeutic properties. Given the importance of PS backbone for interaction with proteins, we systematically replaced anionic PS-linkages in toxic ASOs with charge-neutral alkylphosphonate linkages. Site-specific incorporation of alkyl phosphonates altered the RNaseH1 cleavage patterns but overall rates of cleavage and activity versus the on-target gene in cells and in mice were only minimally affected. However, replacing even one PS-linkage at position 2 or 3 from the 5'-side of the DNA-gap with alkylphosphonates reduced or eliminated toxicity of several hepatotoxic gapmer ASOs. The reduction in toxicity was accompanied by the absence of nucleolar mislocalization of paraspeckle protein P54nrb, ablation of P21 mRNA elevation and caspase activation in cells, and hepatotoxicity in mice. The generality of these observations was further demonstrated for several ASOs versus multiple gene targets. Our results add to the types of structural modifications that can be used in the gap-region to enhance ASO safety and provide insights into understanding the biochemistry of PS ASO protein interactions.


Asunto(s)
Membrana Celular/metabolismo , Citoplasma/metabolismo , Oligonucleótidos Antisentido/química , Organofosfonatos/química , Oligonucleótidos Fosforotioatos/química , Células 3T3-L1 , Animales , Caspasas/metabolismo , Línea Celular , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Proteínas de Unión al ADN , Células HeLa , Hepatocitos/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Proteínas Asociadas a Matriz Nuclear/genética , Proteínas Asociadas a Matriz Nuclear/metabolismo , Factores de Transcripción de Octámeros/genética , Factores de Transcripción de Octámeros/metabolismo , Oligonucleótidos Antisentido/administración & dosificación , Oligonucleótidos Fosforotioatos/administración & dosificación , Unión Proteica , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ribonucleasa H/genética , Ribonucleasa H/metabolismo , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/metabolismo
11.
Zhonghua Yi Xue Za Zhi ; 100(42): 3296-3302, 2020 Nov 17.
Artículo en Zh | MEDLINE | ID: mdl-33202490

RESUMEN

Objective: To analyze the clinical feature,treatment and survival outcome of elderly patients older than 80 years with large diffuse B-cell lymphoma. Methods: A total of 46 patients aged over 80 years with large diffuse B-cell lymphoma who were treated in Third Hospital of Peking University during the period from 2002 to 2018 were retrospectively analyzed, and the clinical features, laboratory data, survival and prognostic factors were included in Kaplan-Meier and prognostic analysis. Results: Patients older than 80 years old accounted for 15.7% (46/293) in all elderly patients, and the median age was 83 years old. There were 78.3% (36/46)patients who belonged to stage Ⅲ or Ⅳ, 63%(29/46) who had more than two extranodal organ involvement, and the higher proliferation index(Ki-67≥80%) was present in 53.7%(22/41) patients. Immunohistochemistry showed that 37% patients in 27 cases were double-expressed DLBCL. With a median follow-up of 25 months, the overall response rate (ORR) for the whole group was 63.0%, the complete response (CR) rate was 36.4%, the 2, 3-year progression-free survival (PFS) rate was 49.9% and 41.7%, the 2, 3-year overall survival (OS) rate was 54.6% and 43.6% respectively. The ORR for patients who received anthracycline-based therapies and non-anthracycline-based therapies were 81.8% and 55.0%, and the 3-year OS rate were 50.0% and 39.0%, respectively, but the difference was not statistically significant (P>0.05). 45.5% patients had hematologic toxicity of Grade Ⅲ or above, and 56.8% patients experienced infections during the treatment. Among the patients who died, the treatment-related mortality rate in group with high score of Charlson comorbidity index(CCI) was higher (43.8% vs 16.7%, P=0.03) . The National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) score, nodal involvement area ≥3, 6 cycles of chemotherapy, CCI score, initial treatment outcome and refractory-relapsed were predictive of overall survival. Multivariate analysis indicated the CCI score (HR=6.463, P=0.008) and initial treatment outcome (HR=0.086, P=0.001) were independent prognostic risk factors. Conclusions: The clinical and pathological features of patients older than 80 years were highly aggressive with poor chemotherapy tolerance and high adverse reaction rate. Anthracycline-based therapies may be less important in the treatment of DLBCL patients aged over 80 years. Patients with high CCI score have higher treatment-related mortality and CCI can help identify elderly patients who are suitable for larger chemotherapy dose.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma de Células B Grandes Difuso , Anciano de 80 o más Años , Ciclofosfamida/uso terapéutico , Doxorrubicina , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Prednisona/uso terapéutico , Pronóstico , Estudios Retrospectivos , Rituximab/uso terapéutico , Resultado del Tratamiento
12.
Acta Endocrinol (Buchar) ; 16(3): 280-287, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33363647

RESUMEN

OBJECTIVES: To assess the effects of electroacupuncture (EA) at the Zusanli (ST36), Guanyuan (CV4), Zhongwan (CV12), and Fenglong (ST40) acupoints on sirtuin 1 (SIRT1) and glucose transporter type 4 (GLUT4) expression in high-fat diet (HFD)-induced insulin-resistant (IR) rats. METHODS: Wistar rats were divided into normal control (NC), HFD, and HFD+EA groups. NC rats were fed a standard chow diet and did not receive EA. After being fed an HFD for eight weeks, rats in the HFD+EA group received EA at 2 Hz five times a week for eight weeks. Rats in the HFD group did not receive EA. RESULTS: In HFD-induced IR rats, EA inhibited body weight increase and water intake, which were observed in HFD rats. EA had no effect on fasting blood glucose and postprandial blood sugar levels. Intraperitoneal insulin tolerance testing revealed that EA enhanced insulin sensitivity in HFD-induced IR rats. Compared with NC rats, SIRT1 and GLUT4 were downregulated in the quadriceps femoris of HFD-fed rats but were increased after eight weeks of EA stimulation. CONCLUSIONS: EA enhanced HFD-induced insulin resistance by activating SIRT1 and GLUT4 in the quadriceps femoris. These results provide powerful evidence supporting the beneficial effects of EA on HFD-induced insulin resistance.

13.
J Neurosci Res ; 97(6): 661-672, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30843634

RESUMEN

There is a lack of knowledge of factors preventing an adequate response to moderate hypothermia after hypoxic ischemic (HI) brain injury. We hypothesized that growth restriction from reduced intrauterine perfusion would predispose neonatal rats to have a worse outcome with HI brain injury. IUGR was induced by placental insufficiency in dams at 14 days of gestation. HI was induced at postnatal day (P) 10 by permanent right carotid artery ligation followed by 90 min of hypoxia (8% oxygen). Tests for early brain injury and neurobehavioral outcomes were subsequently done. All statistical analysis was done using Two-way ANOVA; post hoc Holm-Sidak test. HI in control and IUGR groups decreased the success rate of the contralateral vibrissa-elicited forelimb test, increased response latency in movement initiation test and increased the time to finish elevated beam walk test at P40 and P60. IUGR augmented HI-induced abnormality in vibrissa-elicited forelimb test at P40 but showed higher success rate when compared to HI only group at P60. IUGR's negative effect on HI-induced changes on the elevated beam walk test was sex-specific and exaggerated in P60 males. Increased TUNEL positive cells in the cortex were noted at 72 h after in HI in control but not in IUGR groups. In conclusion, the consequences of IUGR on subsequent neonatal HI varied based on age, sex and outcomes examined, and overall, male sex and IUGR had worse effects on the long-term neurobehavioral outcomes following HI.


Asunto(s)
Encéfalo/fisiopatología , Retardo del Crecimiento Fetal/fisiopatología , Hipoxia-Isquemia Encefálica/fisiopatología , Caracteres Sexuales , Animales , Animales Recién Nacidos , Conducta Animal , Encéfalo/metabolismo , Caspasa 3/metabolismo , Femenino , Retardo del Crecimiento Fetal/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Masculino , Ratas Sprague-Dawley
14.
Zhonghua Wai Ke Za Zhi ; 57(8): 585-590, 2019 Aug 01.
Artículo en Zh | MEDLINE | ID: mdl-31422627

RESUMEN

Objective: To investigate the efficacy and feasibility of laparoscopic resection for gastric gastrointestinal stromal tumor (GIST) in unfavorable location by comparing with open surgery. Methods: Clinicopathological and follow-up data of 176 patients with gastric GIST in unfavorable location admitted at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2005 to December 2017 were analyzed retrospectively. There were 94 males and 82 females, aging of (57.4±12.7) years (range: 20-90 years). Of the 176 patients, 64 underwent laparoscopic surgery (laparoscopic group) and 112 underwent open surgery (open group). One-to-one propensity score matching (PSM) was performed to balance the covariance between laparoscopic group and open surgery group. Before PSM, the differences between the two group in tumor size and modified National Institutes of Health risk classification were significant. After PSM, there were 63 pairs (63 cases in laparoscopic group and 63 cases in open group) and the baseline characteristics were comparable between the two groups(P>0.05). The difference of short-term outcome between the two groups were compared using t test, χ(2) test or Wilcoxon rank-sum test. The survival curve was established by Kaplan-Meier method and the Log-rank test was used to compare the survival of the two groups. Results: The operation time of laparoscopic group was shorter ((141.6±100.6) minutes vs. (100.4±67.7) minutes, t=2.681, P=0.008), the hospitalization cost was higher ((5.2±0.7) ten thousand yuan vs. (4.2±0.8) ten thousand yuan, t=7.357, P=0.000) than open group. The time to first flatus ((49.1±8.2) hours vs. (71.0±4.6) hours, t=-18.482, P=0.000) and preoperative hospital stay ((10.3±6.0) days vs. (14.8±7.6) days, t=-3.717, P=0.000) was shorter in laparoscopic group. With a median follow-up time of 44 months (range: 10 to 154 months), the 1-, 3-, 5-year relapse-free survival rates in the laparoscopic group and open group were 98.3%, 92.1%, 92.1% and 100%, 86.3%, 83.2%, respectively (χ(2)=0.696, P=0.404). The 1-, 3-, 5-year overall survival rates in the laparoscopic group and open group were 96.6%, 94.7%, 94.7% and 100%, 91.1%, 81.4%, respectively (χ(2)=0.366, P=0.545). Conclusions: In experienced medical centers, laparoscopic resection is safe and feasible for GIST in unfavorable location. Compared to open surgery, laparoscopic resection achieves a faster postoperative recovery and a similar long-term prognosis.


Asunto(s)
Gastrectomía/métodos , Tumores del Estroma Gastrointestinal/cirugía , Neoplasias Gástricas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Convalecencia , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Gastrectomía/mortalidad , Tumores del Estroma Gastrointestinal/mortalidad , Humanos , Laparoscopía , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Medición de Riesgo , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
15.
Opt Express ; 26(2): 980-989, 2018 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-29401985

RESUMEN

The authors present an experimental investigation of radio frequency modulation on pulsed terahertz quantum cascade lasers (QCLs) emitting around 4.3 THz. The QCL chip used in this work is based on a resonant phonon design which is able to generate a 1.2 W peak power at 10 K from a 400-µm-wide and 4-mm-long laser with a single plasmon waveguide. To enhance the radio frequency modulation efficiency and significantly broaden the terahertz spectra, the QCLs are also processed into a double-metal waveguide geometry with a Silicon lens out-coupler to improve the far-field beam quality. The measured beam patterns of the double-metal QCL show a record low divergence of 2.6° in vertical direction and 2.4° in horizontal direction. Finally we perform the inter-mode beat note and terahertz spectra measurements for both single plasmon and double-metal QCLs working in pulsed mode. Since the double-metal waveguide is more suitable for microwave signal transmission, the radio frequency modulation shows stronger effects on the spectral broadening for the double-metal QCL. Although we are not able to achieve comb operation in this work for the pulsed lasers due to the large phase noise, the homogeneous spectral broadening resulted from the radio frequency modulation can be potentially used for spectroscopic applications.

16.
Eur J Neurol ; 25(7): 949-e73, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29520900

RESUMEN

BACKGROUND AND PURPOSE: Neuromelanin of the brainstem, which is considered a marker of neurodegeneration in Parkinson's disease (PD), can be detected by T1-weighted neuromelanin-sensitive magnetic resonance imaging (NM-MRI). Our aim was to investigate the NM-MRI features of de novo PD and to determine whether these features are associated with motor and non-motor symptoms in de novo PD patients. METHODS: Fifty-one patients with de novo PD (Hoehn and Yahr stage 1-2) and 28 healthy controls were recruited. All subjects underwent clinical and MRI examinations including an NM-MRI sequence. The width and contrast-to-noise ratio (CNR) of the substantia nigra pars compacta (SNc) and the CNR of the locus coeruleus (LC) were measured on NM-MRI images. RESULTS: Both the width and CNR values of the high intensity signals in the SNc were significantly decreased in the lateral, central and medial SNc parts in de novo PD patients compared to control subjects. The changes in the SNc on NM-MRI were not significantly different between the motor subgroups. The CNR values of the left LC were significantly lower in the PD group than in the control group. Specifically, the subtype of PD patients with depressive symptoms exhibited a significantly lower CNR in the left LC than the control group and PD patients without depressive symptoms. CONCLUSIONS: Substantia nigra pars compacta neuromelanin changes occur across both motor and non-motor (with and without depressive symptoms) subtypes, whilst LC changes are more notable in PD patients with depressive symptoms. Our results may provide new evidence to understand the pathophysiology of non-motor symptoms in PD.


Asunto(s)
Locus Coeruleus/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Melaninas/metabolismo , Enfermedad de Parkinson/diagnóstico por imagen , Sustancia Negra/diagnóstico por imagen , Anciano , Biomarcadores/metabolismo , Femenino , Humanos , Locus Coeruleus/metabolismo , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/metabolismo , Fenotipo , Sustancia Negra/metabolismo
17.
Clin Radiol ; 73(6): 595.e1-595.e7, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29510833

RESUMEN

AIM: To correlate elastic parameters with collagen fibre shape and arrangement features in breast lesions. MATERIALS AND METHODS: Shear-wave elastography (SWE) was used to measure the stiffness of breast lesions in 54 patients before surgical removal. The value of stiffness was expressed as the mean and maximum elasticity (Emean and Emax). Lesions were sliced and stained with picric acid-sirius red to display the extracellular matrix (ECM) collagen fibre. The categories of the collagen fibres were based on the shape and arrangement features, i.e., category 0, wavy collagen fibres similar to normal breast tissue; category 1, taut parallel collagen fibres around tumour nests; category 2, straightened and aligned collagen fibres tending to be perpendicular to the tumour boundary; category 3, collagen fibre in a honeycomb arrangement. Bivariate correlation analysis was used to analyse the relationship between elastic parameters and collagen fibre category. RESULTS: For all 54 lesions, the correlation coefficient between Emean and category was 0.693 (p < 0.001), and between Emax and category was 0.794 (p < 0.001). For 36 malignant lesions, the correlation coefficient between Emean and category was 0.658 (p < 0.001), and between Emax and category was 0.771 (p < 0.001). CONCLUSION: Emean and Emax of breast lesions evaluated by SWE were positively correlated with ECM collagen fibre shape and arrangement category. Changes of ECM collagen fibre shape and arrangement may account for the stiffness variations of breast lesions.


Asunto(s)
Carcinoma de Mama in situ/fisiopatología , Neoplasias de la Mama/fisiopatología , Carcinoma Ductal de Mama/fisiopatología , Colágeno/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Carcinoma de Mama in situ/patología , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Elasticidad/fisiología , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Humanos , Persona de Mediana Edad
18.
Chem Soc Rev ; 46(20): 6124-6147, 2017 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-28745756

RESUMEN

Development of efficient and economic water oxidation catalysts (WOCs) remains a crucial bottleneck on the way to artificial photosynthesis applications. Over the past few decades, WOC research has turned into a fascinating interdisciplinary field that ranges from bio-inspired molecular design over nanomaterials and thin films to solid materials tuning. Under the umbrella of WOC optimization, advanced in situ/operando analytical techniques are being developed as increasingly powerful tools to elucidate the controversial discussions about the molecular or nanoscale nature of many WOCs. More and more of these approaches also enable the monitoring of possible key intermediates as an essential prerequisite for proposing catalytic mechanisms. This review is organized in three main parts: first, recent highlights outline frontiers in WOC development, such as the benefits of connecting molecular WOCs with solids along with the introduction of molecular concepts into heterogeneous WOC research. Next, a brief overview of emerging in situ/operando approaches demonstrates new options for monitoring WOC transformations. Finally, selected monitoring studies over the entire WOC dimensionality spectrum illustrate interesting cases of catalytic border crossings as new input for WOC construction.

19.
Int Endod J ; 50(1): 97-105, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26659859

RESUMEN

AIM: To evaluate nanoparticulate calcium carbonate (NPCC) using transmission electron microscopy and the effects of NPCC addition to MTA in regard to the setting time, dimensional change, compressive strength, solubility and pH. METHODOLOGY: The experimental groups were G1 (MTA), G2 (MTA with 5% NPCC) and G3 (MTA with 10% NPCC). The tests followed ISO and ADA standards. The specimens in the dimensional change and compressive strength tests were measured immediately after setting, after 24 h and after 30 days. In the solubility test, rings filled with cement were weighed after setting and after 30 days. The pH was measured after 24 h and 30 days. The data were analysed with the ANOVA, Tukey's and Kruskal-Wallis tests (α = 5%). RESULTS: The setting time was reduced (P < 0.05) in samples from G2 and G3 compared to G1. After 24 h, the dimensional change was similar amongst the groups, and after 30 days, G2 was associated with less alteration than G1 and G3. There was a difference in the compressive strength (P < 0.001) after 24 h and 30 days (G1 > G2 > G3). The solubility test revealed a difference amongst the groups when the specimens were hydrated: G2 > G1 > G3 and dehydrated: G3 > G2 > G1. The pH of the groups was similar at 24 h with higher values in each group after 30 days (P < 0.05), and G2 and G3 had similar mean pH values but both were higher than G1. CONCLUSIONS: Nanoparticulate calcium carbonate had a cubic morphology with few impurities. The addition of nanoparticulate calcium carbonate to MTA accelerated the setting time, decreased compressive strength and, after 30 days, resulted in lower dimensional change (G2), higher solubility and a higher pH.


Asunto(s)
Compuestos de Aluminio/química , Carbonato de Calcio/química , Compuestos de Calcio/química , Cementos Dentales/química , Ensayo de Materiales , Óxidos/química , Silicatos/química , Fuerza Compresiva , Combinación de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas , Solubilidad
20.
Zhonghua Yi Xue Za Zhi ; 97(32): 2485-2490, 2017 Aug 22.
Artículo en Zh | MEDLINE | ID: mdl-28835053

RESUMEN

Objective: To analyze clinical feature and treatment outcome of young patients with high-risk diffuse large B cell lymphoma. Methods: A total of 122 young patients with high-risk diffuse large B cell lymphoma who were treated in Third Hospital of Peking University during the period from January 2000 to April 2015 were retrospectively analyzed, and the clinical features, laboratory data were included in Kaplan-Meier and prognostic analysis. Results: In our center, the incidence of young high-risk DLBCL was 27.1% in all DLBCL patients, median age was 44.0 years, 99.2% patients belong to Ⅲ and Ⅳstage, 50% patients had more than two extranodal organs involvement, and the higher proliferation index(Ki-67≥80%) was present in 63.1% of patients, Immunohistochemistry showed that 36.7% patients in 30 cases were double-expressed DLBCL. The overall response rate(ORR) for the whole group was 79.4%, the complete response rate was 39.7% , the 3, 5-year progression free survival rate was 59.8% and 57.0%, the 3, 5-year overall survival rate was 63.5% and 57.8%, respectively. 44.3% patients were refractory-relapsed DLBCL. Rituximab can improve the survival of patients and 3-year overall survival rate was 75.2% vs 46.1%(P=0.001). High-dose chemotherapy was superior to CHOP regimen which 3-year overall survival rate was 84.6% vs 54.1%(P=0.006). Compared with chemotherapy group , auto-hematopoietic stem cell transplantation can improve prognosis of patients and 3-year overall survival rate was 93.4% vs 48.3%(P<0.001). The level of Ki-67, B symptom, ECOG score, the level of LDH, WBC and albumin, ESR level, anemia, rituximab therapy, initial regimens, ASCT, initial treatment outcome and refractory-relapsed were predictive of overall survival. Multivariate analysis indicated that albumin level(RR=5.462, P=0.019), initial treatment outcome(RR=34.863, P<0.001) and refractory-relapsed (RR=24.374, P<0.001)were independent prognostic risk factors. Conclusions: Young patients with high-risk DLBCL were highly aggressive in clinical and pathological features . Rituximab and high-dose regimens can improve the survival of patients.


Asunto(s)
Linfoma de Células B Grandes Difuso , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Supervivencia sin Enfermedad , Humanos , Pronóstico , Estudios Retrospectivos , Rituximab , Resultado del Tratamiento
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