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1.
Nature ; 616(7957): 452-456, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36858074

RESUMEN

Some active asteroids have been proposed to be formed as a result of impact events1. Because active asteroids are generally discovered by chance only after their tails have fully formed, the process of how impact ejecta evolve into a tail has, to our knowledge, not been directly observed. The Double Asteroid Redirection Test (DART) mission of NASA2, in addition to having successfully changed the orbital period of Dimorphos3, demonstrated the activation process of an asteroid resulting from an impact under precisely known conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope from impact time T + 15 min to T + 18.5 days at spatial resolutions of around 2.1 km per pixel. Our observations reveal the complex evolution of the ejecta, which are first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and subsequently by solar radiation pressure. The lowest-speed ejecta dispersed through a sustained tail that had a consistent morphology with previously observed asteroid tails thought to be produced by an impact4,5. The evolution of the ejecta after the controlled impact experiment of DART thus provides a framework for understanding the fundamental mechanisms that act on asteroids disrupted by a natural impact1,6.

2.
Nature ; 583(7816): 379-384, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669697

RESUMEN

Magic-angle twisted bilayer graphene (TBG), with rotational misalignment close to 1.1 degrees, features isolated flat electronic bands that host a rich phase diagram of correlated insulating, superconducting, ferromagnetic and topological phases1-6. Correlated insulators and superconductivity have been previously observed only for angles within 0.1 degree of the magic angle and occur in adjacent or overlapping electron-density ranges; nevertheless, the origins of these states and the relation between them remain unclear, owing to their sensitivity to microscopic details. Beyond twist angle and strain, the dependence of the TBG phase diagram on the alignment4,6 and thickness of the insulating hexagonal boron nitride (hBN)7,8 used to encapsulate the graphene sheets indicates the importance of the microscopic dielectric environment. Here we show that adding an insulating tungsten diselenide (WSe2) monolayer between the hBN and the TBG stabilizes superconductivity at twist angles much smaller than the magic angle. For the smallest twist angle of 0.79 degrees, superconductivity is still observed despite the TBG exhibiting metallic behaviour across the whole range of electron densities. Finite-magnetic-field measurements further reveal weak antilocalization signatures as well as breaking of fourfold spin-valley symmetry, consistent with spin-orbit coupling induced in the TBG via its proximity to WSe2. Our results constrain theoretical explanations for the emergence of superconductivity in TBG and open up avenues towards engineering quantum phases in moiré systems.

3.
Gynecol Oncol ; 181: 125-132, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38159362

RESUMEN

OBJECTIVE: To determine the maximum tolerated dose (MTD) of paclitaxel combined with a fixed dose of cisplatin (75 mg/m2) delivered via hyperthermic intraperitoneal chemotherapy (HIPEC) to patients with ovarian cancer. METHODS: This multicenter Phase I trial employed a Bayesian Optimal Interval (BOIN) design. The MTD was determined to have a target dose-limiting toxicity (DLT) rate of 25%. The starting dose was 175 mg/m2. The Data and Safety Monitoring Board made decisions regarding dose escalation or de-escalation in increments of 25 mg/m2 for subsequent patient cohorts, up to a maximum sample size of 30 or 12 patients treated at a given dose. RESULTS: Twenty-one patients participated in this study. Among the three evaluable patients who received 150 mg/m2 paclitaxel, no DLTs were observed. Among the 12 evaluable patients who received 175 mg/m2 paclitaxel, two reported DLTs: one had grade 4 neutropenia and one had grade 4 anemia, neutropenia, and leukopenia. Four of the six evaluable patients who received 200 mg/m2 paclitaxel reported DLTs: one patient had grade 4 diarrhea, one had grade 3 kidney injury, and two had grade 4 anemia. The isotonic estimate of the DLT rate in the 175 mg/m2 dose group was 0.17 (95% confidence interval, 0.02-0.42), and this dose was selected as the MTD. CONCLUSION: Paclitaxel, when combined with a fixed dose of cisplatin (75 mg/m2), can be safely administered intraperitoneally at a dose of 175 mg/m2 in patients with ovarian cancer who received HIPEC (43 °C, 90 min) following cytoreductive surgery.


Asunto(s)
Anemia , Neutropenia , Neoplasias Ováricas , Humanos , Femenino , Cisplatino , Paclitaxel , Quimioterapia Intraperitoneal Hipertérmica , Dosis Máxima Tolerada , Teorema de Bayes , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Ováricas/terapia , Neutropenia/inducido químicamente , Anemia/etiología , Relación Dosis-Respuesta a Droga
4.
BJOG ; 131(7): 952-960, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38168494

RESUMEN

OBJECTIVE: To assess pelvic floor muscle (PFM) strength and influencing factors among healthy women at different life stages. DESIGN: Multicentre cross-sectional study. SETTING: Fourteen hospitals in China. POPULATION: A total of 5040 healthy women allocated to the following groups (with 1680 women per group): premenopausal nulliparous, premenopausal parous and postmenopausal. METHODS: The PFM strength was evaluated by vaginal manometry. Multivariate logistic regression was used to determine the influencing factors for low PFM strength. MAIN OUTCOME MEASURES: Maximum voluntary contraction pressure (MVCP). RESULTS: The median MVCP values were 36, 35 and 35 cmH2O in premenopausal nulliparous (aged 19-51 years), premenopausal parous (aged 22-61 years), and postmenopausal (aged 40-86 years) women, respectively. In the premenopausal nulliparous group, physical work (odds ratio, OR 2.05) was the risk factor for low PFM strength, which may be related to the chronic increased abdominal pressure caused by physical work. In the premenopausal parous group, the number of vaginal deliveries (OR 1.28) and diabetes (OR 2.70) were risk factors for low PFM strength, whereas sexual intercourse (<2 times per week vs. none, OR 0.55; ≥2 times per week vs. none, OR 0.56) and PFM exercise (OR 0.50) may have protective effects. In the postmenopausal group, the number of vaginal deliveries (OR 1.32) and family history of pelvic organ prolapse (POP) (OR 1.83) were risk factors for low PFM strength. CONCLUSIONS: Physical work, vaginal delivery, diabetes and a family history of POP are all risk factors for low PFM strength, whereas PFM exercises and sexual life can have a protective effect. The importance of these factors varies at different stages of a woman's life.


Asunto(s)
Manometría , Fuerza Muscular , Diafragma Pélvico , Posmenopausia , Premenopausia , Vagina , Humanos , Femenino , Persona de Mediana Edad , Estudios Transversales , Diafragma Pélvico/fisiología , Adulto , Manometría/métodos , Fuerza Muscular/fisiología , Anciano , Posmenopausia/fisiología , Premenopausia/fisiología , Vagina/fisiología , Factores de Riesgo , Anciano de 80 o más Años , Adulto Joven , Paridad , China/epidemiología , Contracción Muscular/fisiología , Embarazo
5.
Mol Ther ; 31(7): 2077-2088, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37060176

RESUMEN

OBP-301 is an oncolytic adenovirus modified to replicate within cancer cells and lyse them. This open-label, non-comparative, phase I dose-escalation trial aimed to assess its safety and optimal dosage in 20 patients with advanced hepatocellular carcinoma. Good tolerance was shown with a maximum tolerated dose of 6 × 1012 viral particles. The most common treatment-emergent adverse events were influenza-like illness, pyrexia, fatigue, decreased platelet count, abdominal distension, and anemia. Cohorts 4 and 5 had approximately 50% higher levels of CD8+ T cells in the peripheral blood after injection. The best target response occurred in 14 patients, 4 of whom had progressive disease. Multiple intratumoral injections of OBP-301 were well tolerated in patients with advanced hepatocellular carcinoma. The stable disease rate for the injected tumors was greater than the overall response rate, even with no obvious tumor response. OBP-301 might have a greater impact on local response as histological examination revealed that the presence of OBP-301 was consistent with the necrotic area at the injection site. Increased infiltration of CD8+ T cells and <1% PD-L1 expression were observed in tumors after injection. Improved antitumor efficacy might be achieved in future studies via viral injection with volume adjustment and in combination with other immuno-therapeutics.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Viroterapia Oncolítica , Virus Oncolíticos , Telomerasa , Humanos , Adenoviridae/genética , Carcinoma Hepatocelular/etiología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Línea Celular Tumoral , Viroterapia Oncolítica/efectos adversos , Virus Oncolíticos/genética
6.
Retina ; 44(6): 1021-1025, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38194676

RESUMEN

PURPOSE: To assess the impact of bilateral vision status on vision-related quality of life (VR-QOL) in patients with Type 2 diabetes in a Chinese cohort. METHODS: Patients with presenting visual acuity (PVA) and VR-QOL data from the Fushun Diabetic Retinopathy Cohort Study were included. Vision-related quality of life was assessed using the National Eye Institute Visual Function Questionnaire-25. Monocular PVA (Snellen) was categorized into three levels for both the better-seeing eye and worse-seeing eye: 1) high PVA (H, > 6/18); 2) moderate PVA (M, 6/18-6/60); and 3) low PVA (L, < 6/60). Based on the monocular PVAs, six categories of bilateral vision status were defined (H-H, H-M, H-L, M-M, M-L, and L-L). The parameters of VR-QOL were analyzed between the groups. RESULTS: A total of 1,717 patients were enrolled. For better-seeing eyes in the same PVA level, the Visual Function Questionnaire-25 composite score decreased significantly with declining PVA in the worse-seeing eye (H-M vs. H-L: 80.5 ± 17.9 vs. 73.6 ± 22.5, P = 0.01; M-M vs. M-L: 78.7 ± 19.6 vs. 69.1 ± 26.4, P = 0.01). Conversely, for worse-seeing eyes in the same PVA level, there was no significant difference in the Visual Function Questionnaire-25 composite score as PVA changed in the better-seeing eye (H-M vs. M-M, 80.5 ± 17.9 vs. 78.7 ± 19.6, P = 0.30; H-L vs. M-L: 73.6 ± 22.5 vs. 69.1 ± 26.4, P = 0.25). CONCLUSION: The PVA of the worse-seeing eye in bilateral vision has a greater impact on VR-QOL in diabetic patients. Priority treatment may be considered for the worse-seeing eye for diabetic patients with different bilateral vision statuses, to better improve VR-QOL.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Calidad de Vida , Agudeza Visual , Humanos , Masculino , Agudeza Visual/fisiología , Femenino , Persona de Mediana Edad , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/complicaciones , Retinopatía Diabética/psicología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Encuestas y Cuestionarios , Anciano , Visión Binocular/fisiología , China/epidemiología
7.
Ophthalmologica ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889695

RESUMEN

INTRODUCTION: To compare the long-term outcomes of conventional scleral buckling (CSB), modified scleral buckling (MSB), and scleral encircling (SE) in the treatment of rhegmatogenous retinal detachment and identify factors influencing the outcomes. METHODS: This comparative, retrospective cohort study assigned patients to CSB, MSB, and SE groups. The follow-up was 12 months, and the reattachment rate, complication rate, visual acuity, number of newly discovered tears during surgery, and changes in diopters were compared among the three surgeries. Influential factors on anatomical and functional reattachment were identified. RESULTS: There were no significant differences in the primary reattachment rate, overall complication rate, or best-corrected visual acuity at 6 or 12 months among the three groups. The MSB group had a higher number of newly discovered tears during surgery compared with the other two groups. At 12 months post-surgery, the SE group displayed the greatest change of diopter, whereas the MSB group showed the least change. The surgical approach did not influence the primary reattachment rate. Long-term visual outcomes were influenced by factors including sex, preoperative visual acuity, macular status, and duration of symptoms. CONCLUSION: MSB is an effective method for treating rhegmatogenous retinal detachment. Its advantages include the ability to identify smaller tears and induce minimal changes in diopter.

8.
Ecotoxicol Environ Saf ; 277: 116363, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38663190

RESUMEN

Environmental aflatoxin B1 (AFB1) exposure has been proposed to contribute to hepatocellular carcinoma by promoting liver fibrosis, but the potential mechanisms remain to be further elucidated. Extracellular vesicles (EVs) were recognized as crucial traffickers for hepatic intercellular communication and play a vital role in the pathological process of liver fibrosis. The AFB1-exposed hepatocyte-derived EVs (AFB1-EVs) were extracted, and the functional effects of AFB1-EVs on the activation of hepatic stellate cells (HSCs) were explored to investigate the molecular mechanism of AFB1 exposure-induced liver fibrogenesis. Our results revealed that an environment-level AFB1 exposure induced liver fibrosis via HSCs activation in mice, while the AFB1-EVs mediated hepatotoxicity and liver fibrogenesis in vitro and in vivo. AFB1 exposure in vitro increased PINK1/Parkin-dependent mitophagy in hepatocytes, where upregulated transcription of the PARK2 gene via p53 nuclear translocation and mitochondrial recruitment of Parkin, and promoted AFB1-EVs-mediated mitochondria-trafficking communication between hepatocytes and HSCs. The knockdown of Parkin in HepaRG cells reversed HSCs activation by blocking the mitophagy-related AFB1-EVs trafficking. This study further revealed that the hepatic fibrogenesis of AFB1 exposure was rescued by genetic intervention with siPARK2 or p53's Pifithrin-α (PFTα) inhibitors. Furthermore, AFB1-EVs-induced HSCs activation was relieved by GW4869 pharmaceutic inhibition of EVs secretion. These results revealed a novel mechanism that AFB1 exposure-induced p53-Parkin signal axis regulated mitophagy-dependent hepatocyte-derived EVs to mediate the mitochondria-trafficking intercellular communication between hepatocytes and HSCs in the local hepatotoxic microenvironment to promote the activated HSCs-associated liver fibrogenesis. Our study provided insight into p53-Parkin-dependent pathway regulation and promised an advanced strategy targeting intervention to EVs-mediated mitochondria trafficking for preventing xenobiotics-induced liver fibrosis.


Asunto(s)
Aflatoxina B1 , Vesículas Extracelulares , Células Estrelladas Hepáticas , Hepatocitos , Cirrosis Hepática , Mitofagia , Proteína p53 Supresora de Tumor , Ubiquitina-Proteína Ligasas , Aflatoxina B1/toxicidad , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/patología , Vesículas Extracelulares/efectos de los fármacos , Vesículas Extracelulares/metabolismo , Mitofagia/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Animales , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ratones , Masculino , Humanos , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos
9.
Arch Gynecol Obstet ; 309(4): 1597-1608, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38308732

RESUMEN

PURPOSE: Our study aimed to investigate the best time to manage hydrosalpinx to improve pregnancy outcomes during in vitro fertilization-embryo transfer (IVF-ET). METHODS: Patients with hydrosalpinx who received IVF treatment were analyzed retrospectively. And two groups were included to compare the effects of different timing treatment of hydrosalpinx on IVF pregnancy outcomes, "Proximal Tubal Occlusion First Group" (Group Ligation-COH) and "Oocyte Retrieval First Group" (Group COH-Ligation). The main outcome measures included: ovarian response indexes, laboratory indexes and clinical pregnancy outcomes. Univariate and multivariate Logistic regression analysis was performed for outcome indicators, and the odds ratios (OR) and 95% confidence interval (CI) were used. RESULTS: A total of 1490 patients were included (n = 976 Ligation-COH and n = 514 COH-Ligation). The Gn starting dose and MII rate in group Ligation-COH were significantly higher than those in group COH-Ligation (203.33 ± 58.20 vs. 203.33 ± 58.20, 81.58% vs. 80.28%, P < 0.05). The number of oocytes obtained and the number of available D3 embryos in group COH-Ligation were higher than those in group Ligation-COH (15.10 ± 7.58 vs. 13.45 ± 6.42, 10.92 ± 5.81 vs. 9.94 ± 5.15, P < 0.05). Although the number of ET cycles per IVF cycle in group COH-Ligation was higher than that in group Ligation-COH (1.88 ± 1.00 vs. 1.48 ± 0.70, P < 0.05), the biochemical pregnancy rate, clinical pregnancy rate, multiple pregnancy rate, live birth rate and cumulative live birth rate in group Ligation-COH were significantly higher than those in group COH-Ligation (60.83% vs. 46.27% for biochemical pregnancy, 55.69% vs. 38.5% for clinical pregnancy, 26.18% vs. 17.74% for multiple pregnancy, 47.08% vs. 25.26% for live birth, 69.47% vs. 47.47% for cumulative live birth, P < 0.05), and the miscarriage rate in group Ligation-COH was lower than that in group COH-Ligation (10.47% vs. 17.20 for early abortion, 4.49% vs. 15.86% for late abortion, P < 0.05). In logistic regression analysis, after adjustment for age and multiple factors, the above results were still statistically significant differences (P < 0.001). For elderly patients, the clinical pregnancy rate, multiple birth rate and live birth rate in group Ligation-COH were also higher than those in group COH-Ligation (P < 0.001). No significant differences were detected for patients with diminished ovarian reserve. CONCLUSIONS: For the choice of ligation operation time, we recommend that patients choose tubal ligation first and then ovulation induction and oocyte retrieval treatment.


Asunto(s)
Salpingitis , Esterilización Tubaria , Embarazo , Femenino , Humanos , Anciano , Fertilización In Vitro/métodos , Recuperación del Oocito/métodos , Estudios Retrospectivos , Índice de Embarazo , Inducción de la Ovulación/métodos
10.
Environ Toxicol ; 39(3): 1494-1504, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37994244

RESUMEN

As a synthetic androgen, 17α-methyltestosterone (MT) is widely used in aquaculture to induce sex reversal and may pose a potential risk to aquatic organisms. This ecological risk has attracted the attention of many scholars, but it is not comprehensive enough. Thus, the adverse effects of MT on zebrafish (Danio rerio) were comprehensively evaluated from gonadal histology, as well as the mRNA expression levels of 47 genes related to hypothalamic-pituitary-gonadal (HPG) axis, germ cell differentiation, sex determination, and hypothalamus-pituitary-thyroid (HPT) axis. Adult zebrafish with a female/male ratio of 5:7 were exposed to a solvent control (0.001% dimethyl sulfoxide) and three measured concentrations of MT (5, 51 and 583 ng/L) for 50 days. The results showed that MT had no significant histological effects on the ovaries of females, but the frequency of late-mature oocytes (LMO) showed a downward trend, indicating that MT could induce ovarian suppression to a certain extent. The transcriptional expression of activating transcription factor 4b1 (atf4b1), activating transcription factor 4b2 (atf4b2), calcium/calmodulin-dependent protein kinase II delta 1 (camk2d1), calcium/calmodulin-dependent protein kinase II delta 2 (camk2d2) and calcium/calmodulin-dependent protein kinase II inhibitor 2 (camk2n2) genes in the brain of females increased significantly at all treatment groups of MT, and the mRNA expression of forkhead box L2a (foxl2) and ovarian cytochrome P450 aromatase (cyp19a1a) genes in the ovaries were down-regulated by 5 and 583 ng/L group, which would translate into inhibition of oocyte development. As compared to females, MT had relatively little effects on the reproductive system of males, and only the transcriptional alterations of synaptonemal complex protein 3 (sycp3) and 17-alpha-hydroxylase/17,20-lyase (cyp17) genes were observed in the testes, not enough to affect testicular histology. In addition, MT at all treatments strongly increased corticotropin-releasing hormone (crh) transcript in the brain of females, as well as deiodinase 2 (dio2) transcript in the brain of males. The paired box protein 8 (pax8) gene was significantly decreased at 51 or 583 ng/L of MT in both female and male brains. The above results suggest that MT can pose potential adverse effects on the reproductive and thyroid endocrine system of fish.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Masculino , Femenino , Pez Cebra/metabolismo , Metiltestosterona/metabolismo , Metiltestosterona/farmacología , Eje Hipotálamico-Pituitario-Gonadal , Glándula Tiroides/metabolismo , Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/farmacología , Gónadas , Expresión Génica , Células Germinativas , ARN Mensajero/metabolismo , Factores de Transcripción Activadores/genética , Factores de Transcripción Activadores/metabolismo , Factores de Transcripción Activadores/farmacología , Contaminantes Químicos del Agua/metabolismo
11.
Int Ophthalmol ; 44(1): 3, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38315299

RESUMEN

PURPOSE: To introduce the treatment of diabetic macular edema (DME) with subthreshold micropulse diode laser (SMPL), to summarize the biological impact, therapeutic effects, and safety of this treatment, and to discuss the response to DME when SMPL is combined with anti-vascular endothelial growth factor (anti-VEGF) or steroid. METHODS: The literature search was performed on the PubMed database, with a selection of English-language articles published from 2000 to 2023 with the following combinations of search terms: diabetes macular (o) edema, micropulse laser or subthreshold micropulse laser, anti-vascular endothelial growth factor, and steroid. RESULTS: SMPL is a popular, invisible retinal laser phototherapy that is inexpensive, safe, and effective in the treatment of DME. It can selectively target the retinal pigment epithelium, reduce the expression of pro-inflammatory factors, promote the absorption of macular edema, and exert a similar and lasting clinical effect to traditional lasers. No significant difference was found in the therapeutic effects of SMPL between different wavelengths. However, HbA1c level and pretreatment central macular thickness (CMT) may affect the therapeutic outcomes of SMPL. CONCLUSION: SMPL has a slow onset and produces lasting clinical effects similar to conventional photocoagulation. It has been reported that SMPL combined with the intravitreal anti-VEGF injection can significantly reduce the number of injections without influencing the therapeutic effect, which is essential for clinical applications and research. Although 577 nm SMPL is widely used clinically, there are no standardized protocols for SMPL. Additionally, some important problems regarding the treatment of SMPL require further discussion and exploration.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/cirugía , Edema Macular/diagnóstico , Edema Macular/etiología , Edema Macular/cirugía , Láseres de Semiconductores/uso terapéutico , Factores de Crecimiento Endotelial , Coagulación con Láser/métodos , Esteroides , Resultado del Tratamiento , Tomografía de Coherencia Óptica
12.
Br J Haematol ; 201(5): 982-994, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36872867

RESUMEN

Beta-thalassaemia is an inherited haemoglobin disorder characterised by ineffective erythropoiesis (IE). The detailed pathogenesis of IE remains unclear. In this study, we used single-cell RNA sequencing (scRNA-seq) to examine IE in Th3/+ ß-thalassaemic mice. The results showed that the erythroid group was remarkably expanded, and genes involved in biological processes such as iron metabolism, haeme synthesis, protein folding, and response to heat were significantly upregulated from erythroid progenitors to reticulocytes in ß-thalassaemic mice. In particular, we identified a unique cell population close to reticulocytes, named ThReticulocytes, characterised by a high level of heat shock protein 70 (Hsp70) expression and dysregulation of iron metabolism and haeme synthesis signalling. Treatment of ß-thalassaemic mice with the haeme oxygenase inhibitor tin-mesoporphyrin effectively improved the iron disorder and IE, and the ThReticulocyte population and Hsp70 expression were significantly suppressed. This study revealed in detail the progression of IE at the single-cell level and possibly provided clues to find therapeutic targets in thalassaemia.


Asunto(s)
Talasemia , Talasemia beta , Ratones , Animales , Talasemia beta/metabolismo , Eritropoyesis , Reticulocitos/metabolismo , Hierro/metabolismo
13.
Biochem Biophys Res Commun ; 685: 149160, 2023 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-37922788

RESUMEN

One of the causes of sudden cardiac death is arrhythmia after acute myocardial ischemia. After ischemia, endogenous orphanin (N/OFQ) plays a role in the development of arrhythmias. It is discussed in this paper how nonpeptide orphanin receptor (ORL1) antagonists such as J-113397, SB-612111 and compound-24 (C-24) affect arrhythmia in rats following acute myocardial ischemia and what the optimal concentrations for these antagonists are. The electrocardiogram of the rat was recorded as part of the experiment. The concentrations of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) in the myocardium were measured following euthanasia. Following the use of three antagonists, we found the lowest inflammatory factor concentrations and the smallest number of ischemic arrhythmia episodes. All of them had a small impact on cardiac function. LF/HF values were significantly reduced in all three antagonist groups, suggesting that they are involved in the regulation of sympathetic nerves. In conclusion, pretreatment with the three antagonist groups can effectively reduce the concentration of TNF-α and IL-1ß, and the occurrence of arrhythmias after ischemia can also be significantly reduced. Inflammation and sympathetic activity may be related to the mechanism of action of antagonists.


Asunto(s)
Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Ratas , Animales , Factor de Necrosis Tumoral alfa , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/patología , Arritmias Cardíacas/etiología , Arritmias Cardíacas/patología , Miocardio/patología , Isquemia/patología
14.
J Med Virol ; 95(1): e28280, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36329648

RESUMEN

Severe acute respiratory syndrome coronavirus 2 breakthrough infection in highly vaccinated populations raises study on the effectiveness for inactivated vaccine, including effectiveness of the vaccine dose, the continuance of effectiveness, the effectiveness against severe/critical coronavirus disease 2019 and against secondary attacks. A population of 10 870 close contacts were investigated in a Delta variant's epidemic. The effectiveness of vaccination was estimated in a test-negative case-control study. In addition, serum was used to detect neutralizing antibodies, to explore their correlation to effectiveness. The vaccine effectiveness (VE) values were estimated for populations aged 12 years or older. The overall adjusted VE was 56.2% and a two-dose vaccine was more effective than a one-dose vaccine (56.7% vs. 43.8%). In addition, the population that got the second dose vaccine within 2 months showed higher VE than the population vaccinated for longer than 2 months (61.5% vs. 52.3%). Among the population who vaccinated 2 doses or within 2 months, a higher level of neutralizing antibodies was observed. For infected cases, vaccinated populations showed lower rates of transmission (2.63% vs. 4.36%). Further, those vaccinated cases, who were not found causing transmission, had a higher level of antibodies. The study provided a full view of the effectiveness of inactivated vaccines in a real-world setting. The time-related VE against infection and lower transmission of breakthrough vaccinated cases were observed, which may indicate that a necessity of a booster vaccine to maintain the effectiveness and high level of neutralizing antibody.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Anticuerpos Neutralizantes , COVID-19/prevención & control , Estudios de Casos y Controles , SARS-CoV-2 , Anticuerpos Antivirales
15.
Eur Radiol ; 33(1): 512-522, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35864351

RESUMEN

OBJECTIVES: To investigate the association of sarcopenia, myosteatosis, and sarcopenic obesity with survival outcomes among patients who underwent immunotherapy for advanced hepatocellular carcinoma (HCC). METHODS: In this retrospective analysis, patients who initiated immunotherapy for advanced HCC were enrolled. Sarcopenia and myosteatosis were evaluated on pretreatment CT at L3 level by skeletal muscle index and mean muscle attenuation using predefined cutoff values. Sarcopenic obesity was defined as concurrent sarcopenia and body mass index > 25 kg/m2. The log-rank test and the Cox proportional hazards model were used to compare overall survival (OS) and progression-free survival (PFS). RESULTS: A total of 138 patients was included (discovery cohort n = 111, validation cohort n = 27). In the discovery cohort, patients with sarcopenia exhibited significantly poorer PFS (p = 0.048) and OS (p = 0.002) than patients without sarcopenia. Patients with myosteatosis exhibited significantly poorer PFS (p < 0.001) and OS (p < 0.001) than patients without myosteatosis. Patients with sarcopenic obesity compared to patients without sarcopenic obesity exhibited significantly poorer OS (p = 0.006) but not PFS (p = 0.31). In multivariate analysis adjusting for patient demographics, tumor extent, and liver function reserve, myosteatosis remained an independent predictor of poor PFS (p = 0.014) and OS (p = 0.007); sarcopenia remained an independent predictor for poor OS (p = 0.007). The prediction models for survival outcomes built by the discovery cohort showed similar performance in the validation cohort. CONCLUSIONS: Sarcopenia and myosteatosis are independent prognostic factors in patients who received immunotherapy for advanced HCC. KEY POINTS: • Sarcopenia and myosteatosis can be evaluated by CT at L3 level. • Sarcopenia, myosteatosis, and sarcopenic obesity were associated with poor survival outcomes in patients who underwent immunotherapy for advanced HCC. • Myosteatosis was an independent predictor of PFS and OS, and sarcopenia was independent for OS in these patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sarcopenia , Humanos , Sarcopenia/complicaciones , Sarcopenia/diagnóstico por imagen , Sarcopenia/epidemiología , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/terapia , Estudios Retrospectivos , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/terapia , Pronóstico , Músculo Esquelético/patología , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad/patología , Inmunoterapia
16.
J Org Chem ; 88(13): 8441-8453, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37276376

RESUMEN

Herein, we present a facile synthetic methodology to produce a range of N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides via palladium-mediated C(sp3)-H bond activation. The N-methyl-N-(pyridin-2-yl)benzamide precursor was first reacted with palladium(II) acetate in a stoichiometric manner to obtain the key dinuclear palladacycle intermediates, whose structures were elucidated by mass spectrometric, NMR spectroscopic, and X-ray crystallographic studies in detail. The subsequent C(sp3)-H bond functionalizations on the N-methyl group of the starting substrate show facile productions of the corresponding N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides with good functional group tolerance. A plausible mechanism was proposed based on density functional theory calculations in conjunction with kinetic isotope effect experiments. Finally, the synthetic transformation from the prepared N-(CH2-aryl)-N-(pyridin-2-yl)benzamides through debenzoylation to N-(CH2-aryl)-2-aminopyridine was successfully demonstrated.


Asunto(s)
Benzamidas , Paladio , Paladio/química , Catálisis , Alquilación
17.
Anal Bioanal Chem ; 415(3): 405-410, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36370202

RESUMEN

Sensitive and reliable detection of the p53 gene plays a significant role in precise cancer targeting and in fundamental research. However, the sensitivity of existing p53 gene detection approaches remains to be improved. Herein, we develop a target recognition assisted-primer exchange reaction (Ta-PER) for sensitive analysis of the p53 gene. Ta-PER was initiated by the recognition of a designed dumbbell structure probe by the p53 gene. In Ta-PER, the primer exchange reaction (PER) was combined with molecular beacon-based chain recycling to construct the signal amplification process. Through integrating target recognition with PER-based signal amplification, Ta-PER was established and exhibited a high detection sensitivity, with a limit of detection as low as 56 fM. In addition, the approach was also used to detect the p53 gene in normal HeLa cells and amatoxin-treated HeLa cells. The high level of the p53 gene in amatoxin-treated HeLa cells, which was approximately 1.67 times higher than that in HeLa cell extract, indicated the apoptosis of cells and suggested the promising prospect of the approach.


Asunto(s)
Técnicas Biosensibles , Genes p53 , Humanos , Células HeLa , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos
18.
Anal Bioanal Chem ; 415(4): 715-724, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36520201

RESUMEN

It is highly desirable to develop high-performance ratiometric fluorescent probes for SO2 derivative detection and realize their application in biological imaging. In this study, we report the rational design of a novel negative photochromic spiropyran derivative, spiro[azahomoadamantane-pyran] (MAHD-SP), with notable orange fluorescence in its stable ring-opened state without UV regulation. The unsaturated double bond of MAHD-SP underwent the Michael addition reaction of the SO2 derivative, making the fluorescence quenching of MAHD-SP obvious. Then, MAHD-SP, a fluorescent conjugated polymer PFO and a polymeric surfactant PEO113-b-PS49 were used to construct a ratiometric fluorescent polymeric nanoprobe (RFPN) via a coprecipitation method. The probe exhibited high sensitivity and selectivity for the ratiometric detection of SO2 derivatives in pure aqueous solutions. Moreover, the good biocompatibility of RFPN can be used to visualize exogenous and endogenous SO2 derivative generation in living cells.


Asunto(s)
Benzopiranos , Dióxido de Azufre , Humanos , Dióxido de Azufre/química , Indoles , Microscopía Fluorescente/métodos , Colorantes Fluorescentes/química , Células HeLa
19.
Environ Res ; 216(Pt 2): 114571, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36243047

RESUMEN

Few epidemiological studies have focused on prenatal phthalates (PAEs) and polybrominated diphenyl ethers (PBDEs) exposure to neonatal health in China. This study aimed to assess the associations between prenatal PAEs and PBDEs exposure and neonatal health in Guangxi, a Zhuang autonomous region of China. Concentrations of 4 PAEs metabolites (mPAEs) and 5 PBDEs congeners were measured in the serum of 267 healthy pregnant women. Birth outcomes and clinical data of neonates were collected after delivery. Mono-(2-Ethylhexyl) phthalate (MEHP) (81.52%) and BDE47 (35.21%) were the mPAEs and PBDEs congeners with the highest detection rate in serum. Prenatal exposures to mono-n-butyl phthalate (MBP), MEHP, and ΣmPAEs were negatively associated with birth weight (BW), birth length (BL), and gestational age (GA). Higher exposures to MBP, MEHP, and ΣmPAEs were associated with an increased odds ratio (OR) for low birth weight (LBW), but exposure to BDE28 exhibited the opposite effect. Moreover, higher exposures to MBP, MEHP, ΣmPAEs, BDE99, and ΣPBDEswere associated with an increased OR for premature birth (PTB) (P < 0.05). In contrast to MBP exposure, BDE28 exposure was associated with a higher OR for neonatal jaundice (NNJ) (P < 0.05). The interaction analysis showed a positive interaction between monoethyl phthalate (MEP) and BDE28 on the risk of NNJ and positive interaction between ΣmPAEs and BDE47 on the risk of NNJ. In addition, there are ethnicity-specific associations of prenatal PBDEs exposure with neonatal health in individuals of Zhuang and Han nationalities, and boy neonates were more sensitive to prenatal PBDEs exposure than girl neonates. The results revealed that prenatal exposure to mPAEs and PBDEs might have adverse effects on neonatal development, and the effects might be ethnicity- and sex-specific.


Asunto(s)
Ácidos Ftálicos , Efectos Tardíos de la Exposición Prenatal , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Cohorte de Nacimiento , China/epidemiología , Estudios de Cohortes , Éteres Difenilos Halogenados/toxicidad , Salud del Lactante , Exposición Materna/efectos adversos , Ácidos Ftálicos/toxicidad , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología
20.
Int J Hyperthermia ; 40(1): 2155077, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36603842

RESUMEN

OBJECTIVES: To compare pregnancy outcomes after high-intensity focused ultrasound ablation (HIFU), myomectomy and uterine artery embolization (UAE) for fertility-sparing patients with uterine fibroids and to investigate the possible mechanism of improving pregnancy by HIFU. MATERIALS AND METHODS: A meta-analysis of 54 studies containing 12,367 patients was conducted to compare the pregnancy outcomes of three fertility-sparing therapies. And a retrospective self-control study of 26 patients with uterine fibroids from May 2019 to December 2020 was performed to assess the blood flow impedance of bilateral uterine arteries before and after HIFU. RESULTS: In the analysis by treatment option, the pregnancy rate after myomectomy was 0.43 (95% CI 0.36-0.49), which was higher than 0.18 (95% CI 0.10-0.26) after HIFU, the latter was significantly higher than that after UAE (ratio 0.08, 95% CI 0.06-0.10). The miscarriage rate after HIFU was 0.08 (95% CI 0.04-0.12), which was similar to 0.15 (95% CI 0.09-0.21) after myomectomy and also similar to 0.16 after UAE (95% CI 0.01-0.30). In the subgroup analysis, women who received ultrasound guided HIFU (USgHIFU) were more likely to have ideal pregnancy outcomes than that after magnetic resonance imaging-guided HIFU. The pulsatility index and resistance index on the right side were significantly higher 3 months after HIFU than before (1.637 ± 0.435 vs. 1.845 ± 0.469; p = 0.033; 0.729 ± 0.141 vs. 0.784 ± 0.081, p = 0.039). CONCLUSIONS: HIFU, especially USgHIFU, may be an alternative fertility-sparing modality for patients with uterine fibroids over 40 years old. HIFU may contribute to improving pregnancy rates by elevating uterine blood flow impedance.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación , Leiomioma , Neoplasias Uterinas , Embarazo , Humanos , Femenino , Adulto , Neoplasias Uterinas/cirugía , Neoplasias Uterinas/patología , Estudios Retrospectivos , Resultado del Tratamiento , Leiomioma/cirugía , Leiomioma/patología
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