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1.
Nature ; 607(7918): 301-306, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831604

RESUMO

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial-interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

2.
J Chem Phys ; 160(21)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38832742

RESUMO

The isotope shifts in electron affinities of Pb were measured by Walter et al. [Phys. Rev. A 106, L010801 (2022)] to be -0.002(4) meV for 207-208Pb and -0.003(4) meV for 206-208Pb by scanning the threshold of the photodetachment channel Pb-(S3/2◦4) - Pb (3P0), while Chen and Ning reported 0.015(25) and -0.050(22) meV for the isotope shifts on the binding energies measured relative to 3P2 using the SEVI method [J. Chem. Phys. 145, 084303 (2016)]. Here we revisited these isotope shifts by using our second-generation SEVI spectrometer and obtained -0.001(15) meV for 207-208Pb and -0.001(14) meV for 206-208Pb, respectively. In order to aid the experiment by theory, we performed the first ab initio theoretical calculations of isotope shifts in electron affinities and binding energies of Pb, as well as the hyperfine structure of 207Pb-, by using the MCDHF and RCI methods. The isotope shifts in electron affinities of 207-208Pb and 206-208Pb are -0.0023(8) and -0.0037(13) meV for the 3P0 channel, respectively, in good agreement with Walter et al.'s measurements. The isotope shifts in binding energies relative to 3P1,2, -0.0015(8) and -0.0026(13) meV for 207-208Pb and 206-208Pb, respectively, are compatible with the present measurements. The hyperfine constant for the ground state of 207Pb- obtained by the present calculations, A(S3/2◦4)=-1118 MHz, differs by a factor of 3 from the previous estimation by Bresteau et al. [J. Phys. B: At., Mol. Opt. Phys. 52, 065001 (2019)]. The reliability is supported by the good agreement between the theoretical and experimental hyperfine parameters of 209Bi.

3.
J Math Biol ; 89(1): 4, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750128

RESUMO

A system of partial differential equations is developed to study the spreading of tau pathology in the brain for Alzheimer's and other neurodegenerative diseases. Two cases are considered with one assuming intracellular diffusion through synaptic activities or the nanotubes that connect the adjacent cells. The other, in addition to intracellular spreading, takes into account of the secretion of the tau species which are able to diffuse, move with the interstitial fluid flow and subsequently taken up by the surrounding cells providing an alternative pathway for disease spreading. Cross membrane transport of the tau species are considered enabling us to examine the role of extracellular clearance of tau protein on the disease status. Bifurcation analysis is carried out for the steady states of the spatially homogeneous system yielding the results that fast cross-membrane transport combined with effective extracellular clearance is key to maintain the brain's healthy status. Numerical simulations of the first case exhibit solutions of travelling wave form describing the gradual outward spreading of the pathology; whereas the second case shows faster spreading with the buildup of neurofibrillary tangles quickly elevated throughout. Our investigation thus indicates that the gradual progression of the intracellular spreading case is more consistent with the clinical observations of the development of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Encéfalo , Simulação por Computador , Conceitos Matemáticos , Doenças Neurodegenerativas , Proteínas tau , Proteínas tau/metabolismo , Humanos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Neurológicos , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Modelos Biológicos , Progressão da Doença , Tauopatias/metabolismo , Tauopatias/patologia
4.
Zhonghua Nei Ke Za Zhi ; 63(10): 996-1000, 2024 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-39375119

RESUMO

From October 2021 to February 2023, we retrospectively analyzed the clinical and laboratory data of six patients (three male and three female, median age: 54 years, age range: 29-73 years) with mast cell leukemia (MCL) diagnosed in the First Affiliated Hospital of Soochow University (The Mastocytosis Collaborative Network of China). All patients had acute MCL, with at least one C-finding present. The main clinical presentations were hypoalbuminemia (n=4), fatigue (n=3), fever (n=2), abdominal discomfort (n=2), osteolytic lesions (n=2), dizziness (n=1), skin flushing (n=1), and weight loss (n=1). Splenomegaly and lymphadenopathy were noted in six and three patients, respectively. Six patients were strongly positive for CD117, five were positive for CD30 and CD25, and four were positive for CD2. Four patients had a normal karyotype and two patients had an abnormal karyotype. Gene mutations were detected in 4/6 cases. The median serum tryptase level was 24.9 (range: 20.1-171.9) µg/L. Two patients were treated with venetoclax and azacitidine for induction (one patient achieved partial remission by combination with afatinib, while there was no remission after combination with dasatinib in the other patient). Two patients did not achieve complete remission despite treatment with cladribine and imatinib, respectively. One patient treated with interferon combined with glucocorticoids was lost to follow-up, and one patient abandoned treatment. The follow-up time ranged from 1.1 to 21.7 months. Three patients died and two survived. Overall, MCL is a rare subtype of systemic mastocytosis with heterogeneous clinical course, and these patients have poor outcome. A better understanding of the clinical characteristics, treatment, and prognosis of MCL is urgently needed.


Assuntos
Leucemia de Mastócitos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Azacitidina/uso terapêutico , Leucemia de Mastócitos/diagnóstico , Leucemia de Mastócitos/tratamento farmacológico , Leucemia de Mastócitos/genética , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Estudos Retrospectivos
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(10): 1514-1523, 2024 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-39428236

RESUMO

Objective: To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China. Methods: Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust. Results: The M (Q1, Q3) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑12PBDEs in Luoyang and Shijiazhuang (P<0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ß (95%CI): 0.186 (0.013, 0.359)], infrequent home cooking [ß (95%CI):-0.342 (-0.570, -0.114)], and increased residential PM10 concentration [ß (95%CI): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ß (95%CI): 0.093 (0.013, 0.172)], house area less than 90 m2 [ß (95%CI):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ß (95%CI):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑12PBDEs in household dust. Conclusion: The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.


Assuntos
Poluição do Ar em Ambientes Fechados , Cidades , Poeira , Monitoramento Ambiental , Éteres Difenil Halogenados , China , Poeira/análise , Éteres Difenil Halogenados/análise , Poluição do Ar em Ambientes Fechados/análise , Humanos , Estações do Ano , Inquéritos e Questionários , Características da Família
6.
Zhonghua Bing Li Xue Za Zhi ; 53(11): 1122-1126, 2024 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-39482050

RESUMO

Objective: To investigate the clinicopathological characteristics of giant cell tumor of bone (GCTB) in children. Methods: A total of 35 cases of GCTB diagnosed at Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University School from 2016 to 2023 were collected, and a retrospective analysis of clinicopathological features and imaging findings was conducted. Results: Pediatric GCTB accounted for approximately 4.6% of total GCTB cases during the study period. There were 11 males and 24 females. The onset age ranged from 9 to 18 years (mean age 15 years, median age 16 years), with 8 cases (8/35, 22.9%) experiencing postoperative recurrence. Twenty-eight cases (28/35, 80%) primarily affected long bones, while 7 cases involved small or irregular bones. Imaging revealed osteolytic changes as the predominant feature, with 3 cases exhibited open physis, one of which had the tumor primarily at the diaphysis without crossing the physis. Histologically, pediatric GCTB resembled adult cases, characterized by mononuclear cells and osteoclast-like giant cells. Seven cases with denosumab treatment demonstrated degrees of giant cell disappearance, increased fibrous tissue and reactive bone proliferation in the stroma. One case was diagnosed as pediatric multicentric GCTB, and three cases as pediatric primary malignant GCTB, with malignant transformation into osteosarcoma. In all 35 cases, mutations in the H3F3A gene were identified, comprising 32 cases with H3.3 p.G34W mutations, one case with H3.3 p.G34V mutation, and 2 cases with H3.3 p.G34L mutations. Notably, the former two categories were successfully validated at the protein level through immunohistochemical staining, utilizing highly specific antibodies tailored for these mutation types: H3.3 p.G34W antibody and H3.3 p.G34V antibody. However, immunohistochemical staining was not available for the last category. Conclusions: Pediatric GCTB predominantly affects females and occurs primarily in long bones, mainly around the knee joint, the majority of tumors predominantly arise in the epiphysis and extend into the metaphysis; however, in cases where the epiphyseal plates are still unclosed, the tumors may be restricted to the metaphysis. Detection of H3F3A gene mutation is crucial for the diagnosis and differential diagnosis of pediatric GCTB.


Assuntos
Neoplasias Ósseas , Denosumab , Tumor de Células Gigantes do Osso , Humanos , Tumor de Células Gigantes do Osso/patologia , Tumor de Células Gigantes do Osso/genética , Adolescente , Masculino , Feminino , Criança , Neoplasias Ósseas/patologia , Neoplasias Ósseas/genética , Estudos Retrospectivos , Denosumab/uso terapêutico , Histonas/genética , Histonas/metabolismo , Recidiva Local de Neoplasia , Mutação
7.
Zhonghua Fu Chan Ke Za Zhi ; 58(12): 896-902, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38123195

RESUMO

Objective: To investigate the clinical characteristics and maternal and fetal prognosis of pregnant women with acute fatty liver of pregnancy (AFLP). Methods: The clinical data of 86 AFLP pregnant women admitted to the Third Affiliated Hospital of Guangzhou Medical University from September 2017 to August 2022 were collected, and their general data, clinical characteristics, laboratory tests and maternal and fetal outcomes were retrospectively analyzed. Results: (1) General information: the age of the 86 pregnant women with AFLP was (30.8±5.4) years, and the body mass index was (21.0±2.5) kg/m2. There were 50 primiparas (58.1%, 50/86) and 36 multiparas (41.9%, 36/86). There were 64 singleton pregnancies (74.4%, 64/86) and 22 twin pregnancies (25.6%, 22/86). (2) Clinical characteristics: the main complaints of AFLP pregnant women were gastrointestinal symptoms, including epigastric pain (68.6%, 59/86), nausea (47.7%, 41/86), anorexia (46.5%, 40/86), vomiting (39.5%, 34/86). The main non-gastrointestinal symptoms were jaundice of skin and/or scleral (54.7%, 47/86), edema (38.4%, 33/86), fatigue (19.8%, 17/86), bleeding tendency (16.3%, 14/86), polydipsia or polyuria (14.0%, 12/86), skin itching (8.1%, 7/86), and 17.4% (15/86) AFLP pregnant women had no obvious symptoms. (3) Laboratory tests: the incidence of liver and kidney dysfunction and abnormal coagulation function in AFLP pregnant women was high, and the levels of blood ammonia, lactate dehydrogenase and lactic acid were increased, and the levels of hemoglobin, platelet and albumin decreased. However, only 24 cases (27.9%, 24/86) of AFLP pregnant women showed fatty liver by imageology examination. (4) Pregnancy outcomes: ① AFLP pregnant women had a high incidence of pregnancy complications, mainly including renal insufficiency (95.3%, 82/86), preterm birth (46.5%, 40/86), hypertensive disorders in pregnancy (30.2%, 26/86), gestational diabetes mellitus (36.0%, 31/86), fetal distress (24.4%, 21/86), pulmonary infection (23.3%, 20/86), disseminated intravascular coagulation (16.3%, 14/86), multiple organ dysfunction syndrome (16.3%, 14/86), hepatic encephalopathy (9.3%, 8/86), and intrauterine fetal death (2.3%, 2/86). ② Treatment and outcome of AFLP pregnant women: the intensive care unit transfer rate of AFLP pregnant women was 66.3% (57/86). 82 cases were improved and discharged after treatment, 2 cases were transferred to other hospitals for follow-up treatment, and 2 cases (2.3%, 2/86) died. ③ Neonatal outcomes: except for 2 cases of intrauterine death, a total of 106 neonates were delivered, including 39 cases (36.8%, 39/106) of neonatal asphyxia, 63 cases (59.4%, 63/106) of neonatal intensive care unit admission, and 3 cases (2.8%, 3/106) of neonatal death. Conclusions: AFLP is a severe obstetric complication, which is harmful to mother and fetus. In the process of clinical diagnosis and treatment, attention should be paid to the clinical manifestations and laboratory tests of pregnant women, early diagnosis and active treatment, so as to improve maternal and fetal outcomes.


Assuntos
Fígado Gorduroso , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Adulto , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/diagnóstico , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico , Morte Fetal , Natimorto
8.
Eur Cell Mater ; 43: 252-266, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35652679

RESUMO

Polyethylene terephthalate (PET) artificial ligaments offer an unlimited source of ligaments without donor-site-related morbidity and with good mechanical properties for a rapid return to sporting activities. Developing PET artificial ligaments with excellent ligamentisation and ligament-bone healing is still a considerable challenge. This study aimed to investigate the effects of the profiled PET/collagen/calcium phosphate (PET/C/CaP) ligament upon cell growth, ligamentisation and ligament-bone healing in vitro and in vivo. Profiled PET/C/CaP filaments were made by melt-spinning process with 2 % CaP hybrid spinning and collagen coating. Rat mesenchymal stem cells (MSCs) were cultured on the profiled PET/C filaments for cytotoxicity, viability, scanning electron microscopy (SEM) and ligament-related gene expression analysis. MSCs' osteogenic capacity on the profiled PET/CaP filaments was identified by detecting osteogenic gene expression and alizarin red S staining. For in vivo verification, an animal study was performed to evaluate the effect of the profiled PET/C/CaP ligament in a rabbit knee medial collateral ligament reinforcement reconstruction model. The graft ligamentisation and bone formation were investigated by SEM, histology, microcomputed tomography and mechanical tests. The profiled PET/C filaments enhanced MSC proliferation and ligament-related gene expression. Furthermore, they enhanced osteogenic gene expression, alkaline phosphatase activity and mineralisation of MSCs. The in vivo study indicated that the profiled PET/C/CaP ligament enhanced ligamentous matrix remodelling and bone formation. Therefore, their use is an effective strategy for promoting MSCs' ligamentous and osteogenic potential in vitro and enhancing ligamentous matrix remodelling and bone formation in vivo.


Assuntos
Osteogênese , Polietilenotereftalatos , Animais , Fosfatos de Cálcio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Colágeno/metabolismo , Colágeno/farmacologia , Polietilenotereftalatos/farmacologia , Coelhos , Ratos , Microtomografia por Raio-X
9.
Nutr Neurosci ; 25(7): 1466-1476, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33448906

RESUMO

BACKGROUND: Age-related cognitive decline is a major public health issue. Almonds are rich in nutrients that benefit cognitive function. OBJECTIVE: To investigate the impact of almonds on cognition in elderly adults. DESIGN: In a six-month, single-blinded, randomized-controlled trial, the effects of an almond intervention on cognition in healthy, middle-aged/older adults (50-75 years) was tested. Subjects were assigned to one of three groups: 1.5 oz/d almond (n = 19), 3 oz/d almond (n = 24), or 3.5 oz/d snack (control, matched for macronutrients in 3.0 oz almonds, (n = 17). Serum analyses for tocopherols, oxidative status and inflammation, and cognition were assessed at baseline (M0), three (M3), and six (M6) months. RESULTS: At M6, serum alpha-tocopherol concentrations increased by 8% from M0 (p < 0.05) in the 3 oz almond group but did not increase in the other groups. Serum markers of inflammation and oxidative stress were not significantly different throughout the study among the groups. There was no difference in change over time in cognitive tests among the groups. However, there was a significant improvement in visuospatial working memory (p = 0.023), visual memory and learning (p = 0.017), and spatial planning and working memory (p < 0.001) in subjects receiving 3 oz/d almonds at M6, while the snack group showed no improvement. CONCLUSIONS: Almonds did not significantly improve cognitive function in cognitively intact middle-aged/older adults over six months. However, a significant improvement at M6 in cognitive measures was observed with 3 oz/d almonds. While these results are encouraging, a study of longer duration in subjects at risk for age-related cognitive decline is warranted.Trial registration: ClinicalTrials.gov identifier: NCT03093896.


Assuntos
Disfunção Cognitiva , Prunus dulcis , Idoso , Cognição , Disfunção Cognitiva/prevenção & controle , Humanos , Inflamação , Pessoa de Meia-Idade , Lanches
10.
Osteoporos Int ; 32(6): 1061-1070, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33415375

RESUMO

Situational factors might help explain why most vertebral fractures occur in older people without a previous osteoporosis diagnosis. After adjusting for predisposing risk factors, the activity before the fall, type of fall, and falling direction remained as strong determinants of fall-related vertebral fractures in older men and women. INTRODUCTION: A matched case-control study was conducted to investigate the effects of situational factors, in addition to predisposing factors, on clinical vertebral fractures in older men and women in Taiwan. METHODS: Cases were community-dwelling individuals aged ≥ 65 years who visited emergency departments (EDs) of two university-affiliated hospitals due to a fall and had a primary diagnosis of a vertebral fracture during a 1-year period in 2017. Five control patients per case, matched by the time of falling, gender, and age, who sought care in the same ED due to a fall resulting in a soft tissue injury were selected. A total of 64 men (age range: 65 ~ 99 years) and 194 women (age range: 65 ~ 100 years), diagnosed with a vertebral fracture, participated in the study. RESULTS: Multivariable logistic models were conducted separately for men and women. Results suggested that the following factors were significantly associated with an increased risk of vertebral fractures in men: a low educational level (adjusted odds ratio [OR] = 1.95; 95% confidence interval (CI), 1.02 ~ 3.71), asthma (OR = 2.96; 95% CI, 1.35 ~ 6.92), depression (OR = 4.31; 95% CI, 1.03 ~ 17.5), toileting (OR = 2.30; 95% CI, 1.04 ~ 4.94), slipping (OR = 5.27; 95% CI, 1.80 ~ 15.4), stepping down (OR = 3.99; 95% CI, 1.40 ~ 11.4), sudden leg weakness (OR = 3.73; 95% CI, 1.13 ~ 12.4), and falling backwards (OR = 3.78; 95% CI, 1.83 ~ 7.80); and in women: a fracture history (OR = 2.00; 95% CI, 1.07 ~ 3.76), osteoporosis (OR = 1.94; 95% CI, 1.15 ~ 3.49), getting in/out of the bed/chair (OR = 1.90; 95% CI, 1.07 ~ 3.39), stepping down (OR = 2.10; 95% CI, 1.17 ~ 3.77), and falling backwards (OR = 4.00; 95% CI, 2.39 ~ 6.68) and sideways (OR = 2.61; 95% CI, 1.38 ~ 4.96). CONCLUSIONS: The combination of predisposing and situational risk factors may display a more comprehensive risk profile for the occurrence of VFs, and thus, interventions that add both types of risk factors may result in greater risk reduction of VFs, although those specifically targeted at situational risk factors during falls are limited and their effectiveness and efficiency remained to be explored.


Assuntos
Acidentes por Quedas , Fraturas da Coluna Vertebral , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Taiwan/epidemiologia
11.
Phys Rev Lett ; 124(5): 057404, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083911

RESUMO

We investigate the quasiparticle dynamics in the prototypical heavy fermion CeCoIn_{5} using ultrafast optical pump-probe spectroscopy. Our results indicate that this material system undergoes hybridization fluctuations before the establishment of heavy electron coherence, as the temperature decreases from ∼120 K (T^{†}) to ∼55 K (T^{*}). We reveal that the anomalous coherent phonon softening and damping reduction below T^{*} are directly associated with the emergence of collective hybridization. We also discover a distinct collective mode with an energy of ∼8 meV, which may be experimental evidence of the predicted unconventional density wave. Our findings provide important information for understanding the hybridization dynamics in heavy fermion systems.

12.
Crit Rev Food Sci Nutr ; 60(13): 2174-2211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31267783

RESUMO

Fruit and vegetables (F&V) have been a cornerstone of healthy dietary recommendations; the 2015-2020 U.S. Dietary Guidelines for Americans recommend that F&V constitute one-half of the plate at each meal. F&V include a diverse collection of plant foods that vary in their energy, nutrient, and dietary bioactive contents. F&V have potential health-promoting effects beyond providing basic nutrition needs in humans, including their role in reducing inflammation and their potential preventive effects on various chronic disease states leading to decreases in years lost due to premature mortality and years lived with disability/morbidity. Current global intakes of F&V are well below recommendations. Given the importance of F&V for health, public policies that promote dietary interventions to help increase F&V intake are warranted. This externally commissioned expert comprehensive narrative, umbrella review summarizes up-to-date clinical and observational evidence on current intakes of F&V, discusses the available evidence on the potential health benefits of F&V, and offers implementation strategies to help ensure that public health messaging is reflective of current science. This review demonstrates that F&V provide benefits beyond helping to achieve basic nutrient requirements in humans. The scientific evidence for providing public health recommendations to increase F&V consumption for prevention of disease is strong. Current evidence suggests that F&V have the strongest effects in relation to prevention of CVDs, noting a nonlinear threshold effect of 800 g per day (i.e., about 5 servings a day). A growing body of clinical evidence (mostly small RCTs) demonstrates effects of specific F&V on certain chronic disease states; however, more research on the role of individual F&V for specific disease prevention strategies is still needed in many areas. Data from the systematic reviews and mostly observational studies cited in this report also support intake of certain types of F&V, particularly cruciferous vegetables, dark-green leafy vegetables, citrus fruits, and dark-colored berries, which have superior effects on biomarkers, surrogate endpoints, and outcomes of chronic disease.


Assuntos
Dieta Saudável , Frutas , Política Nutricional , Verduras , Ingestão de Alimentos , Humanos , Estudos Observacionais como Assunto , Revisões Sistemáticas como Assunto , Estados Unidos
13.
Colorectal Dis ; 22(1): 6-17, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260150

RESUMO

AIM: The clinical benefits of a combination of leucovorin and fluorouracil have been established in the treatment of colorectal cancer. Due to a leucovorin shortage in 2008, many institutions revised their protocols to reduce the dose of leucovorin. After the shortage was resolved, some hospitals still maintained their modified protocols. Thus, we conducted a systematic review to evaluate the efficacy and safety of low- vs high-dose leucovorin in the treatment of colorectal cancer. METHOD: The PubMed, Embase and Cochrane databases were searched for studies published before May 2019. The meta-analysis was performed to estimate the pooled effect sizes by using a random effect model. The primary outcomes were median survival time and tumour response rate. Secondary outcomes were haematological and nonhaematological toxicities. RESULTS: Eight randomized controlled trials and four retrospective studies were reviewed. The pooled median survival time was similar between the two dose levels (standard mean difference -0.06, 95% CI -0.19 to 0.08). The pooled tumour response rate was comparatively higher in the high-dose leucovorin regimen (OR 0.81; 95% CI 0.55-1.18). No statistically significant difference was found between the haematological and nonhaematological toxicities of the two groups. However, there were fewer diarrhoea events in the low-dose leucovorin regimen. CONCLUSION: Low-dose leucovorin regimens seemed feasible approaches for colorectal cancer treatment when the shortage happened, because both regimens manifested comparable outcomes in survival time and tumour response rate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/administração & dosagem , Leucovorina/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Estudos de Viabilidade , Feminino , Humanos , Leucovorina/provisão & distribuição , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
14.
J Intensive Care Med ; 35(8): 797-804, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30021499

RESUMO

Ubiquinol is a fundamental component of cellular metabolism. Low ubiquinol levels have been associated with mortality. This was a substudy of a randomized trial in patients undergoing coronary artery bypass grafting. We drew blood before and after surgery. Ubiquinol or placebo was added to peripheral blood mononuclear cells for oxygen consumption (OCR) measurements. In vivo ubiquinol levels were lower postsurgery compared to presurgery (0.16 µmol/L [quartiles: 0.02-0.39], P = .01), although the difference disappeared when adjusting for hemoglobin levels (P = .30). There was no difference in presurgical basal (1.0 mL/min/mg [95% confidence interval [CI]: -0.9 to 2.2], P = .08) and maximal (0.5 mL/min/mg [95% CI: -4.3 to 7.3], P = .56) OCR in cells receiving ubiquinol or placebo. There was a difference in postsurgical basal (1.1 mL/min/mg [95% CI: 0.9-1.6], P < .001) and maximal (4.2 mL/min/mg [95% CI: 0.3-7.0], P = .01) OCR between the groups. We found no association between ubiquinol and OCR levels (all P > .05).


Assuntos
Ponte de Artéria Coronária , Leucócitos Mononucleares/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Ubiquinona/análogos & derivados , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Período Pós-Operatório , Período Pré-Operatório , Ensaios Clínicos Controlados Aleatórios como Assunto , Ubiquinona/administração & dosagem , Ubiquinona/sangue
15.
Public Health Nutr ; 23(5): 935-955, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31599222

RESUMO

OBJECTIVE: This umbrella review provides an overview of the consistency and gaps in the evidence base on eggs and cardiometabolic health. DESIGN: PubMed, Web of Science, Cochrane Library, the Nutrition Evidence Systematic Review and Agency for Healthcare Research and Quality databases were screened for evidence-based reviews in English that assessed human studies on egg consumption and cardiometabolic outcomes. RESULTS: Seven systematic reviews and fifteen meta-analyses were identified, with eighteen of these published since 2015. Overall, the systematic reviews were of low quality, while meta-analyses were of moderate- to high-quality. No association of increased egg intake and risks of heart disease or stroke in the general population were found in the meta-analyses. Increased risk of heart failure was noted in two meta-analyses that analysed the same three cohort studies. Five recent meta-analyses reported no increased risk of type 2 diabetes mellitus (T2DM) in the general population, although increased risk in US-based populations only has been reported. Older (<2013) meta-analyses reported increased risks of cardiovascular disease (CVD) or heart disease in T2DM populations, and no recent evidence-based reviews were identified. Finally, only one meta-analysis reported intervention studies specifically on eggs and biomarkers (i.e. lipids), and the results contradicted those from observation studies. CONCLUSIONS: Recent evidence-based reviews conclude that increased egg consumption is not associated with CVD risk in the general population. More research is needed on the positive associations between egg consumption and heart failure and T2DM risk, as well as CVD risk in diabetics, before firm conclusions can be made.


Assuntos
Doenças Cardiovasculares/epidemiologia , Ovos , Doenças Metabólicas/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Ovos/efeitos adversos , Feminino , Cardiopatias/epidemiologia , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Revisões Sistemáticas como Assunto
16.
Br Poult Sci ; 61(4): 465-470, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32216555

RESUMO

1. The present study focused on the potential effects of antibiotics on intestinal digestion and integrity in broilers in terms of disaccharidase activity, electrophysiological properties and morphology. 2. One-day-old Arbour Acres birds were randomly allocated to one of four treatment groups for 42 days; control, colistin (20 mg/kg), tylosin (55 mg/kg) or chlortetracycline (CTC, 55 mg/kg) groups. Colistin and tylosin supplementation, but not CTC supplementation, caused an increase in body weight gain. 3. Colistin and tylosin elevated the activities of maltase and sucrase in the mucosa of the jejunum on d 42. Age caused a gradual decrease in the short-circuit current (Isc) and conductance (Gt) of the ileum, as a measure of permeability. The Isc and Gt of the ileum were higher in the colistin-supplemented broilers than in the control birds on d 42. Tylosin- and CTC-supplemented birds displayed Isc and Gt values similar to those of the control birds. 4. Colistin supplementation increased the villus area in the jejunum and thinned the muscularis mucosae in the ileum compared with the control group. Tylosin supplementation decreased the thickness of the muscularis mucosae and the depth of crypt in the jejunum. CTC thickened the muscularis mucosae in the jejunum and ileum. 5. Colistin and tylosin exhibited a beneficial effect on intestinal digestion and integrity by enhancing disaccharidase activities and improving gut morphology and permeability.


Assuntos
Ração Animal , Galinhas , Suplementos Nutricionais , Tilosina , Ração Animal/análise , Animais , Colistina , Dieta , Dissacaridases , Permeabilidade
17.
Zhonghua Nei Ke Za Zhi ; 59(1): 40-46, 2020 Jan 01.
Artigo em Chinês | MEDLINE | ID: mdl-31887835

RESUMO

Objective: To investigate the association between adherens junction proteins E-cadherin and ß-catenin and tight junction protein claudin-2 and clinical symptoms in patients with diarrhea predominant irritable bowel syndrome (IBS-D). Methods: Cecal biopsy tissues were collected from IBS-D patients (n=26) according to Rome Ⅲ criterion and healthy controls (n=26). The duration of symptoms, abdominal pain score and mean weekly bowel movements were recorded. Colorectal dilatation combined with restraint stress were applied to establish visceral hypersensitivity rat model. Abdominal contraction reflex (AWR) was applied to assess the visceral sensitivity in rats. The stool frequency within 1 hour was recorded after establishing the rat model. The expression of E-cadherin、ß-catenin and claudin-2 were assessed by Western blot and immunofluorescence microscopy. Intercellular ultrastructure was observed by transmission electron microscopy. Results: Compared with the healthy controls, the protein expression of E-cadherin and ß-catenin in cecal epithelium in IBS-D patients were significantly lower (P=0.015 and P=0.005, respectively), while claudin-2 was significantly higher (P=0.000). Reduced E-cadherin and ß-catenin expression was associated high abdominal pain score (r=-0.463, P=0.017 and r=-0.407, P=0.039). The lower expression of ß-catenin was associated with longer duration of symptoms (r=-0.458, P=0.019). The protein expression of E-cadherin and ß-catenin in the cecal epithelium of the visceral hypersensitivity rats were significantly lower (P=0.004 and P=0.003, respectively), while claudin-2 was significantly higher (P=0.008). Reduced E-cadherin and ß-catenin expression was associated high visceral sensitivity in IBS-D rats (r=-0.639, P=0.047 and r=-0.888, P=0.001). Conclusions: Intercellular ultrastructure alterations well as cecal ß-catenin and E-cadherin protein expression decrease and are associated with high abdominal pain score in IBS-D patients and hypersensitivity rats. ß-catenin is further associated with prolonged duration of symptoms in IBS-D patients. The expression of E-cadherin and ß-catenin may play a vital role in visceral sensitivity and intestinal barrier dysfunction in IBS-D.


Assuntos
Junções Aderentes/metabolismo , Caderinas/metabolismo , Síndrome do Intestino Irritável/metabolismo , Junções Íntimas/metabolismo , Dor Abdominal/metabolismo , Dor Abdominal/fisiopatologia , Animais , Biópsia , Estudos de Casos e Controles , Ceco/metabolismo , Claudina-2 , Diarreia/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Síndrome do Intestino Irritável/patologia , Ratos , beta Catenina
18.
Zhonghua Gan Zang Bing Za Zhi ; 28(9): 803-808, 2020 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-33053983

RESUMO

Chronic liver disease has gradually become a serious health problem worldwide. Liver biopsy is the current gold standard to assess liver lesions; however, it is an invasive procedure that may cause severe complications. Therefore, there is an urgent need for an economical and rapid non-invasive detection method that can be used in clinic for diagnosis. In the past decade, protein glycosylation has become a research hotspot, and the concept of changes in serum proteoglycans structure has gradually been accepted by many researchers as an indication of liver injury. At the same time, N-linked glycans via DNA sequencing equipment-Fluorophore Assisted Carbohydrate Electrophoresis (DSA-FACE) has also brought high sensitivity and specificity diagnostic models (GlycoHepatoTest) for various chronic liver diseases, which is a new strategy for non-invasive diagnosis of liver diseases.


Assuntos
Glicômica , Hepatopatias , Carboidratos , Eletroforese , Humanos , Hepatopatias/diagnóstico , Polissacarídeos , Análise de Sequência de DNA , Tecnologia
19.
Zhonghua Gan Zang Bing Za Zhi ; 28(12): 1023-1029, 2020 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-34865350

RESUMO

Objective: To study the changes of serum N-glycan abundance in patients with liver fibrosis at different stages of hepatitis C, and to establish and evaluate the diagnostic model for clinical application value. Methods: Data of 169 hepatitis C virus-infected cases with liver fibrosis were enrolled. Nine kinds of serum N-glycans were detected and analyzed using DNA sequencer-assisted fluorophore-assisted capillary electrophoresis technology. A binary logistics regression method was used to establish a diagnostic model based on the changes in the relative content of N-glycans in each stage of liver fibrosis. Receiver operating characteristic curve was used to evaluate and compare the diagnostic efficacy with other liver fibrosis diagnostic models. Results: N-glycan diagnostic model (B and C) had highest AUROC= 0.776, 0.827 for distinguishing fibrosis S1~S2 to S3~S4 and S1~S3 to S4 than GlycoFibroTest (AUROC = 0.760, 0.807), GlycoCirrhoTest (AUROC = 0.722, 0.787), aspartate aminotransferase to platelet ratio index (AUROC = 0.755, 0.751), FIB-4 index (AUROC = 0.730, 0.774), and S-index (AUROC = 0.707, 0.744). However, the diagnostic efficacy of model A (AUROC = 0.752) for distinguishing fibrosis S1 with S2~S4 had lower diagnostic potency than that of the aspartate aminotransferase to platelet ratio index (AUROC = 0.807). Diagnostic efficiency was improved when the N-glycan profiling and the aspartate aminotransferase to platelet ratio index were combined to diagnose liver fibrosis in each stage, and the area under the receiver operating characteristic curve was 0.839, 0.825, and 0.837, respectively. Conclusion: The serum N-glycan profiling diagnostic model has potential clinical application value in the diagnosis of liver fibrosis in patients with hepatitis C.


Assuntos
Hepacivirus , Hepatite C , Aspartato Aminotransferases , Humanos , Cirrose Hepática/diagnóstico , Polissacarídeos
20.
Theor Popul Biol ; 126: 1-18, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30165060

RESUMO

In-host mutation of a cross-species infectious disease to a form that is transmissible between humans has resulted with devastating global pandemics in the past. We use simple mathematical models to describe this process with the aim to better understand the emergence of an epidemic resulting from such a mutation and the extent of measures that are needed to control it. The feared outbreak of a human-human transmissible form of avian influenza leading to a global epidemic is the paradigm for this study. We extend the SIR approach to derive a deterministic and a stochastic formulation to describe the evolution of two classes of susceptible and infected states and a removed state, leading to a system of ordinary differential equations and a stochastic equivalent based on a Markov process. For the deterministic model, the contrasting timescale of the mutation process and disease infectiousness is exploited in two limits using asymptotic analysis in order to determine, in terms of the model parameters, necessary conditions for an epidemic to take place and timescales for the onset of the epidemic, the size and duration of the epidemic and the maximum level of the infected individuals at one time. Furthermore, the basic reproduction number R0 is determined from asymptotic analysis of a distinguished limit. Comparisons between the deterministic and stochastic model demonstrate that stochasticity has little effect on most aspects of an epidemic, but does have significant impact on its onset particularly for smaller populations and lower mutation rates for representatively large populations. The deterministic model is extended to investigate a range of quarantine and vaccination programmes, whereby in the two asymptotic limits analysed, quantitative estimates on the outcomes and effectiveness of these control measures are established.


Assuntos
Influenza Aviária/genética , Influenza Aviária/transmissão , Influenza Humana/epidemiologia , Modelos Biológicos , Mutação , Animais , Doenças Transmissíveis/epidemiologia , Simulação por Computador , Surtos de Doenças , Humanos , Influenza Aviária/epidemiologia , Influenza Humana/prevenção & controle , Cadeias de Markov , Aves Domésticas/virologia , Quarentena , Processos Estocásticos , Vacinação
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