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1.
Proc Natl Acad Sci U S A ; 120(45): e2304179120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903265

RESUMO

The unexpected discovery of hot Jupiters challenged the classical theory of planet formation inspired by our solar system. Until now, the origin and evolution of hot Jupiters are still uncertain. Determining their age distribution and temporal evolution can provide more clues into the mechanism of their formation and subsequent evolution. Using a sample of 383 giant planets around Sun-like stars collected from the kinematic catalogs of the Planets Across Space and Time project, we find that hot Jupiters are preferentially hosted by relatively younger stars in the Galactic thin disk. We subsequently find that the frequency of hot Jupiters declines with age as [Formula: see text]. In contrast, the frequency of warm/cold Jupiters shows no significant dependence on age. Such a trend is expected from the tidal evolution of hot Jupiters' orbits, and our result offers supporting evidence using a large sample. We also perform a joint analysis on the planet frequencies in the stellar age-metallicity plane. The result suggests that the frequencies of hot Jupiters and warm/cold Jupiters, after removing the age dependence are both correlated with stellar metallicities as [Formula: see text] and [Formula: see text], respectively. Moreover, we show that the above correlations can explain the bulk of the discrepancy in hot Jupiter frequencies inferred from the transit and radial velocity (RV) surveys, given that RV targets tend to be more metal-rich and younger than transits.

2.
World J Diabetes ; 14(8): 1271-1279, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37664482

RESUMO

BACKGROUND: The prevalence of diabetes mellitus (DM) in China is high, and the base is broad. Diabetic retinopathy (DR) is a critical condition affecting the life and health of a nation and its economic development. DR is a common complication of DM. AIM: To investigate the efficacy of laser photocoagulation combined with intravitreal injection of conbercept for treating macular edema. METHODS: Overall, 130 patients with diabetic macular edema (DME) hospitalized in The Third People's Hospital of Changzhou from January 2019 to June 2022 were retrospectively included. According to the treatment plan, 130 patients with DME were categorized into an observation and a control group, with 65 patients in each group. The control group received laser photocoagulation, and the observation group received laser photocoagulation with intravitreal injection of conbercept. Observe changes in vision, cytokines in the eye and so on. RESULTS: The total efficacy rate in the observation group (93.85%) was higher than that in the control group (78.46%) (P < 0.05). In both groups, the best corrected visual acuity correction effect improved after treatment, and the observation group was superior to the control group (P < 0.05). Retinal thickness and central macular thickness improved after treatment, and the observation group was superior to the control group (P < 0.05). The levels of vascular endothelial growth factor, interleukin-6, soluble intercellular adhesion molecule-1, and basic fibroblast growth factor in both groups improved after treatment, and the observation group was superior to the control group (P < 0.05). CONCLUSION: In patients with macular edema, combining laser photocoagulation and intravitreal injections of conbercept for DME is a more effective and safer strategy to improve vision, and lower intraocular cytokine levels.

3.
Proc Natl Acad Sci U S A ; 115(2): 266-271, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29284755

RESUMO

We discover a population of short-period, Neptune-size planets sharing key similarities with hot Jupiters: both populations are preferentially hosted by metal-rich stars, and both are preferentially found in Kepler systems with single-transiting planets. We use accurate Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data Release 4 (DR4) stellar parameters for main-sequence stars to study the distributions of short-period [Formula: see text] Kepler planets as a function of host star metallicity. The radius distribution of planets around metal-rich stars is more "puffed up" compared with that around metal-poor hosts. In two period-radius regimes, planets preferentially reside around metal-rich stars, while there are hardly any planets around metal-poor stars. One is the well-known hot Jupiters, and the other one is a population of Neptune-size planets ([Formula: see text]), dubbed "Hoptunes." Also like hot Jupiters, Hoptunes occur more frequently in systems with single-transiting planets although the fraction of Hoptunes occurring in multiples is larger than that of hot Jupiters. About [Formula: see text] of solar-type stars host Hoptunes, and the frequencies of Hoptunes and hot Jupiters increase with consistent trends as a function of [Fe/H]. In the planet radius distribution, hot Jupiters and Hoptunes are separated by a "valley" at approximately Saturn size (in the range of [Formula: see text]), and this "hot-Saturn valley" represents approximately an order-of-magnitude decrease in planet frequency compared with hot Jupiters and Hoptunes. The empirical "kinship" between Hoptunes and hot Jupiters suggests likely common processes (migration and/or formation) responsible for their existence.

4.
Proc Natl Acad Sci U S A ; 113(41): 11431-11435, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671635

RESUMO

The nearly circular (mean eccentricity [Formula: see text]) and coplanar (mean mutual inclination [Formula: see text]) orbits of the solar system planets motivated Kant and Laplace to hypothesize that planets are formed in disks, which has developed into the widely accepted theory of planet formation. The first several hundred extrasolar planets (mostly Jovian) discovered using the radial velocity (RV) technique are commonly on eccentric orbits ([Formula: see text]). This raises a fundamental question: Are the solar system and its formation special? The Kepler mission has found thousands of transiting planets dominated by sub-Neptunes, but most of their orbital eccentricities remain unknown. By using the precise spectroscopic host star parameters from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) observations, we measure the eccentricity distributions for a large (698) and homogeneous Kepler planet sample with transit duration statistics. Nearly half of the planets are in systems with single transiting planets (singles), whereas the other half are multiple transiting planets (multiples). We find an eccentricity dichotomy: on average, Kepler singles are on eccentric orbits with [Formula: see text] 0.3, whereas the multiples are on nearly circular [Formula: see text] and coplanar [Formula: see text] degree) orbits similar to those of the solar system planets. Our results are consistent with previous studies of smaller samples and individual systems. We also show that Kepler multiples and solar system objects follow a common relation [[Formula: see text](1-2)[Formula: see text]] between mean eccentricities and mutual inclinations. The prevalence of circular orbits and the common relation may imply that the solar system is not so atypical in the galaxy after all.

5.
World J Gastroenterol ; 11(21): 3227-33, 2005 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15929172

RESUMO

AIM: To investigate the mRNA expressions of bFGF and MMP-9 in gastric carcinomas so as to reveal their correlations with tumor microvascular density (MVD), invasion, metastasis, and prognosis. METHODS: In situ hybridization and immunohistochemical techniques were used to detect the expressions of bFGFmRNA and MMP-9mRNA and the proteins of CD34 in 105 specimens of gastric carcinomas. RESULTS: In situ hybridization study showed that positive rates of bFGF mRNA and MMP-9mRNA expressions were 60.95% and 59.19%; the mean MVD was 46.09+/-11.52 and 43.75+/-13.41, respectively in piece/0.72 mm(2) in tumors with bFGFmRNA and MMP-9mRNA positive expressions, which were significantly higher than those with negative expression (29.41+/-12.47; 33.45+/-13.92 piece/0.72 mm(2), respectively). The positive expression rates of bFGFmRNA and MMP-9mRNA were correlated to the tumor invasion depth (r(s) = 0.211, P = 0.031; r(s) = 0.335, P = 0.001), growing pattern (r(s) = 0.324, P = 0.001; r(s) = 0.267, P = 0.006), vessel invasion (r(s) = 0.579, P = 0.001; r(s) = 0.209, P = 0.032), lymph node metastasis (r(s) = 0.405, P = 0.001; r(s) = 0.343, P = 0.001) and distant metastasis (r(s) = 0.474, P = 0.001; r(s) = 0.468, P = 0.001), but not correlated to tumor type (r(s) = 0.134, P = 0.173; r(s) = 0.103, P = 0.145) and differentiations (r(s) = 0.096, P = 0.332; r(s) = 0.102, P = 0.298). The mean MVD was much higher in the tumors with infiltrating growth at stage T(3)-T(4), with vessel invasion, lymph node metastasis and distant metastasis than those with expanding growth type (t = 10.105, P = 0.001) at stage T(1)-T(2) (t = 5.961, P = 0.001), with non-vessel invasion (t = 7.394, P = 0.001), non-lymph node metastasis (t = 3.819, P = 0.01) and non-distant metastasis (t = 10.578, P = 0.001). Positive correlation was observed between MVD and the expressions of bFGFmRNA and MMP-9mRNA (t = 3.207, P = 0.002; t = 7.035, P = 0.001, respectively). The mean survival time and 5-year survival rate were lower in cases with MVD over 39.5 and the positive expressions of bFGFmRNA and MMP-9mRNA than those with MVD less than 39.5 and the negative expressions of bFGFmRNA and MMP-9mRNA. CONCLUSION: bFGF and MMP-9 promote the angiogenesis of the gastric cancers. Detection of the expressions of bFGF and MMP-9 can serve as a useful index to determine the angiogenesis, invasion, metastasis, and prognosis of gastric cancers.


Assuntos
Fator 2 de Crescimento de Fibroblastos/genética , Metaloproteinase 9 da Matriz/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/fisiopatologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/fisiopatologia , Prognóstico , RNA Mensageiro/análise , Neoplasias Gástricas/irrigação sanguínea
6.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 5598-602, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281525

RESUMO

To study the effects of 4-hydroxy-2-nonenal (HNE) on cultured human aortic endothelial cells and myocardial cells so as to explore the mechanism of the pathogenesis of atherosclerosis. In situ cell death technique, quantitative DNA damage detection and immunohistochemistry were used to identify the cell apoptosis and DNA damage in cultured human aortic endothelial cells and myocardial cells. Tail moment was 32.80+/-1.12, 44.30+/-0.99 and 74.6+/-0.97 when HAOEC were treated with 5 muM, 10muM and 15 muM of HNE for 10 hours, which were of statistical significance when compared with the normal group (6.0+/-0.67, P < 0.001 respectively), But when HAOEC was treated with 1 muM of HNE, the tail moment was 11.3+/-0.9, which was of no statistical difference compared with the untreated group(P>0.05). When human aortic endothelial cells (HAOEC) were treated with 5 muM, 10muM and 15 muM of HNE for 10 hours, the percent of nonviable cells were 5.70+/-0.55, 25.96+/-2.02 and 50.80+/-3.40 (P<0.001 respectively when compared with the normal group with the percent of 0.27+/-0.13). But when HAOEC was treated with 1 muM of HNE for 10 hours, the percent of nonviable cells was 2.5+/-0.22, and no difference was observed when compared with the untreated group (P>0.05). When cultured human myocardial cells were treated with 5 muM of HNE for 10 hours, TUNEL staining showed a greater number of apoptotic cells in HNE-treated human myocardial cells. No TUNEL-positive cells were observed in untreated group. When HAOEC was treated with 5 muM of HNE for 10 hours, immunocytochemical labeling with polyclonal antibody to HNE-modified proteins revealed specific cytoplasmic staining in cells incubated with HNE, whereas staining was absent in control cells incubated with vehicle. But 1 muM of HNE treatment didn't present positive stainings. Higher concentrations of HNE (10 muM and 15 muM) showed much stronger positive stainings. HNE induces DNA damage and cell apoptosis of cultured aortic endothelial cells and myocardial cells. The DNA damage and apoptosis levels are proportional to the HNE concentrations.

7.
Chin Med J (Engl) ; 117(10): 1536-40, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15498379

RESUMO

BACKGROUND: The aim of this study was to investigate DNA content and expression of c-erbB-2, PS2, and prostate-specific antigen (PSA) proteins in breast carcinomas with neuroendocrine (NE) cell differentiation. METHODS: Chromogranin, c-erbB-2, PS2, and PSA in 131 samples of breast cancer were detected immunohistochemically. Classic Feulgen staining image analysis techniques were used to quantify DNA content in 81 of the breast cancer samples. RESULTS: The c-erbB-2 positive rate in breast carcinoma samples containing neuroendocrine cells was 37.5% and the rate of high expression of c-erbB-2 (++ or +++) was 33.3%, both significantly lower than that in breast carcinomas without neuroendocrine cells (62.6% and 68.7%, respectively, P < 0.05). The rates of positive PS2 and PSA expression in breast carcinoma samples containing neuroendocrine cells were 72.2% and 55.0%, respectively, both significantly higher than that in breast carcinoma samples without neuroendocrine cells (45.0% and 16.4%, respectively, P < 0.05). In NE(+) samples, the integral optical density, DNA index, DNA stemline peak, > 5 c aneuploidy cells, and rate of aneuploidy among cells were all lower than that in NE(-) breast carcinomas (P < 0.01). In NE(+) grade I or II breast carcinomas, these indices were also all lower than that in the NE(-) breast carcinoma samples (P < 0.01). CONCLUSION: Breast carcinomas with neuroendocrine differentiation have a lower rate of malignancy. Neuroendocrine differentiation could serve as a prognostic marker in clinical practice.


Assuntos
Neoplasias da Mama/patologia , Sistemas Neurossecretores/citologia , Neoplasias da Mama/química , Diferenciação Celular , DNA/análise , Feminino , Humanos , Proteínas de Membrana/análise , Presenilina-2 , Antígeno Prostático Específico/análise , Receptor ErbB-2/análise
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 25(2): 204-6, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12905722

RESUMO

OBJECTIVE: To investigate the relationship between diabetes and somatostatin (SOM). METHODS: We established a streptozocin-induced diabetic rats model and studied the changes of SOM mRNA in hippocampi of diabetic and normal rats by using in situ hybridication and computer image analysis. We studied the mechanism of chronic diabetes encephalopathy by observing the changes of somatostatin mRNA in the hippocampus of diabetic rats was studied. RESULT: The number, light density and average area of positive cells in dentate gyrus area of hippocampus in diabetes model were reduced significantly as compared with normal rats (P < 0.01). CONCLUSION: A decline in SOM mRNA expression may play a role in chronic diabetes encephalopathy because of SOM effect in brain.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Hipocampo/metabolismo , Somatostatina/biossíntese , Animais , Encefalopatias/etiologia , Encefalopatias/metabolismo , Giro Denteado/metabolismo , Neuropatias Diabéticas/metabolismo , Masculino , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Somatostatina/genética
9.
World J Gastroenterol ; 9(4): 858-61, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12679948

RESUMO

AIM: To investigate the incidence of neuroendocrine (NE) cells and their hormone products in adenocarcinomas and evaluate their significance in clinical pathology and prognosis. METHODS: By using tissue sectioning and immunocyto-chemistry, 356 cases of adenocarcinomas were studied to examine the presence of chromorgranin and polypeptide hormones in adenocarcinoma samples from our hospital. RESULTS: The positive rate of NE cells and hormone products was 41.5 % (54/130) and 59.3 % (32/54), respectively in large intestinal adenocarcinoma cases; 39.6 % (38/96) and 36.8 % (14/38), respectively in gastric cancer cases; 38.1 % (8/21) and 50.0 % (4/8), respectively in prostatic cancer cases; 21.0 % (17/81) and 17.6 % (3/17), respectively in breasr cancer cases; 17.9 % (5/28) and 60.0 % (3/5), respectively in pancreatic cancer cases. Among carcinomas of large intestine, pancreas and breast, the highly differentiated NE cell numbers were higher than the poorly differentiated NE cell numbers; while the gastric carcinoma cases had more poorly differentiated NE cells than highly differentiated NE cells. The higher detection rate of NE cells and their hormone products, the higher 5-year survival rate among the large intestine cancer cases. CONCLUSION: Close correlation was observed between NE cells and their hormone products with the cancer differentiations. For colorectal carcinomas, there is a close correlation of the presence of NE cells and their hormone products with the tumor staging and prognosis.


Assuntos
Adenocarcinoma/patologia , Norepinefrina/análise , Serotonina/análise , Somatostatina/análise , Neoplasias Gástricas/patologia , Hormônio Adrenocorticotrópico/análise , Biomarcadores/análise , Calcitonina/análise , Gastrinas/análise , Glucagon/análise , Humanos , Neoplasias Intestinais/patologia , Excisão de Linfonodo , Metástase Linfática/patologia , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia
10.
Shi Yan Sheng Wu Xue Bao ; 36(5): 397-400, 2003 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-14724954

RESUMO

To evaluate protection of vitamin C on blue light-induced DNA damage of human retinal pigment epithelium (RPE) cells. The cultured RPE cells were divided into 3 groups: Control group (no blue light exposure), blue light exposure group (blue light exposure for 20 minutes) and blue light exposure + vitamin C group (blue light exposure + 100 mumol/L vitamin C). Travigen's comet assay kit and Euclid comet assay software were used to assay the DNA damage levels. The DNA percentage in the tail of electrophoretogram in the three groups were 18.44%, 54.42% and 32.43% respectively (p < 0.01). Tail moments were 8.2, 48.3, and 18.4 respectively (p < 0.01). Blue light could induce DNA damage to RPE cells but vitamin C could protect the RPE cells from the blue light-induced DNA damage.


Assuntos
Ácido Ascórbico/farmacologia , Dano ao DNA , Luz/efeitos adversos , Epitélio Pigmentado Ocular/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Células Cultivadas , Ensaio Cometa , Humanos , Epitélio Pigmentado Ocular/citologia , Epitélio Pigmentado Ocular/efeitos da radiação
11.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 31(4): 291-292, 2002 08.
Artigo em Chinês | MEDLINE | ID: mdl-12601913

RESUMO

OBJECTIVE: To provide the anatomical basis for the repair of the soft tissue defects on the dorsum of the foot. METHODS: Sixty-eight low extremity specimens were taken from fresh cadavers. The arterial distributions of the foot were observed by perfusing red latex, barium sulfate, Chinese ink and 10% gelatin, also studied by X-ray angiography and microdissection. RESULTS: The blood supply of the lateral pedal region was ensured by the lateral tarsal artery and perforating branch of the peroneal artery. The external diameter of the lateral tarsal artery was 0.9+/-0.2 0.5 approximate, equals 1.8 mm while external diameter of the perforating branch of the peroneal artery was 1.2+/-0.3 0.5 approximate, equals 2.1 mm. CONCLUSION: The lateral pedal musculocutaneous flap can be devised according to the different repair regions to restore the defected soft tissues of the foot.

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