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1.
Neurobiol Dis ; 188: 106335, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37890560

RESUMO

BACKGROUND: Recent animal model studies have suggested that the parafascicular nucleus has the potential to be an effective deep brain stimulation target for Parkinson's disease. However, our knowledge on the role of the parafascicular nucleus in Parkinson's disease patients remains limited. OBJECTIVE: We aimed to investigate the functional alterations of the parafascicular nucleus projections in Parkinson's disease patients. METHODS: We enrolled 72 Parkinson's disease patients and 60 healthy controls, then utilized resting-state functional MRI and spectral dynamic causal modeling to explore the effective connectivity of the bilateral parafascicular nucleus to the dorsal putamen, nucleus accumbens, and subthalamic nucleus. The associations between the effective connectivity of the parafascicular nucleus projections and clinical features were measured with Pearson partial correlations. RESULTS: Compared with controls, the effective connectivity from the parafascicular nucleus to dorsal putamen was significantly increased, while the connectivity to the nucleus accumbens and subthalamic nucleus was significantly reduced in Parkinson's disease patients. There was a significantly positive correlation between the connectivity of parafascicular nucleus-dorsal putamen projection and motor deficits. The connectivity from the parafascicular nucleus to the subthalamic nucleus was negatively correlated with motor deficits and apathy, while the connectivity from the parafascicular nucleus to the nucleus accumbens was negatively associated with depression. CONCLUSION: The present study demonstrates that the parafascicular nucleus-related projections are damaged and associated with clinical symptoms of Parkinson's disease. Our findings provide new insights into the impaired basal ganglia-thalamocortical circuits and give support for the parafascicular nucleus as a potential effective neuromodulating target of the disease.


Assuntos
Núcleos Intralaminares do Tálamo , Doença de Parkinson , Núcleo Subtalâmico , Animais , Humanos , Doença de Parkinson/diagnóstico por imagem , Putamen , Gânglios da Base , Núcleo Subtalâmico/diagnóstico por imagem
2.
Hum Brain Mapp ; 44(3): 1070-1078, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334274

RESUMO

The serotonergic (5-HT) system, which undergoes degeneration in Parkinson's disease (PD), is involved in the pathogenesis of motor and nonmotor symptoms. The dorsal raphe (DR) and median raphe (MR) nuclei are the main source of 5-HT neurons, however, brain connectivity changes in these two nuclei have not been delineated in PD. Here we used resting-state fMRI (rs-fMRI) to characterize functional connectivity profiles of DR and MR and further examine the associations between dysconnectivity of raphe nuclei and clinical phenotypes of PD. We found that DR and MR commonly hypo-connected with the sensorimotor, temporal, and occipital cortex, limbic system, left thalamus, putamen, and cerebellum in PD. DR had unique decreased connectivity with the bilateral prefrontal and cingulate cortices, while MR had lower connectivity with the pons. Moreover, reduced connectivity of DR correlated with depression, drowsiness, and anxiety, whereas dysconnectivity of MR correlated with depression, cognitive deficits, sleep disturbances, and pain. Our findings highlight the complex roles of raphe nuclei in motor and nonmotor symptoms, providing novel insights into the neurophysiological mechanisms underlying pathogenesis of PD.


Assuntos
Doença de Parkinson , Serotonina , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Encéfalo , Sistema Límbico/patologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética
3.
Lipids Health Dis ; 22(1): 3, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631854

RESUMO

BACKGROUND: The triglyceride-glucose index (TyG index), an alternative indicator of peripheral insulin resistance (IR), is associated with cardiovascular disease (CVD) in the general population. The aim of this research was to determine the correlation between early-onset stroke and the TyG index among young Chinese adults. METHODS: Participants (age ≤ 40 years) who attended their first physical examination in Kailuan General Hospital or its 11 subsidiary hospitals between 2006 and 2012 were enrolled. The subjects were divided into four equal points according to the quartile of the TyG index, with the lowest quartile (Q1) as the reference group. A Cox proportional hazard model was employed to assess the correlation between early-onset stroke incidence and the TyG index. Restricted cubic spline analysis was further conducted to examine nonlinear associations. The TyG index was calculated as Ln [Triglyceride (TG, mg/dL) × Fasting Blood Glucose (FBG, mg/dL)/2]. RESULTS: Overall, 35,999 subjects met the inclusion criteria. Their mean age was 30.8 ±  5.7 years, and 77.1% of subjects were males. During a median observation period of 11 years, 281 stroke events occurred (62 hemorrhagic strokes and 219 ischemic strokes). Compared to the Q1 group (as the lowest group), subjects in groups Q2-Q4 had significantly higher risks of early-onset stroke (P < 0.05) after adjustment for relevant confounders in the Cox proportional hazards model. Similar results were consistent with ischemic stroke. However, no significant associations were observed between the risk of hemorrhage and the baseline TyG index. The restricted cubic splines revealed that the risk of stroke progressively increased with a high TyG index ≥ 8.41. CONCLUSIONS: The TyG index may be a major risk factor for early-onset stroke among young Chinese adults. A TyG index ≥ 8.41 can be used as an indicator for screening high-risk stroke groups.


Assuntos
Glicemia , Acidente Vascular Cerebral , Triglicerídeos , Feminino , Humanos , Masculino , Idade de Início , Biomarcadores/sangue , Glicemia/análise , População do Leste Asiático , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Triglicerídeos/sangue , Adulto Jovem , China/epidemiologia
4.
Proc Natl Acad Sci U S A ; 117(31): 18251-18257, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690701

RESUMO

The Yellow River (YR) is the fifth-longest and the most sediment-laden river in the world. Frequent historical YR flooding events, however, have resulted in tremendous loss of life and property, whereas in recent decades YR runoff and sediment load have fallen sharply. To put these recent changes in a longer-term context, we reconstructed natural runoff for the middle reach of the YR back to 1492 CE using a network of 31 moisture-sensitive tree-ring width chronologies. Prior to anthropogenic interference that started in the 1960s, the lowest natural runoff over the past 500 y occurred during 1926 to 1932 CE, a drought period that can serve as a benchmark for future planning of YR water allocation. Since the late 1980s, the low observed YR runoff has exceeded the natural range of runoff variability, a consequence of the combination of decreasing precipitation and increasing water consumption by direct and indirect human activities, particularly agricultural irrigation. This reduced runoff has resulted in an estimated 58% reduction of the sediment load in the upper reach of the YR and 29% reduction in the middle reach.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Modelos Teóricos , Rios , Poluentes Químicos da Água , China , Atividades Humanas , Humanos , Movimentos da Água
5.
Eur Neurol ; 85(6): 467-477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35853433

RESUMO

BACKGROUND: Spinocerebellar ataxia type 12 (SCA12) is a rare SCA subtype with unclear clinical and imaging features. Also, the radiological changes in prodromal and early stages remain unknown. METHODS: Ten symptomatic and two pre-symptomatic cases from three Chinese pedigrees received clinical assessments and imaging studies including routine magnetic resonance imaging (MRI), diffusion kurtosis imaging (DKI), and positron emission tomography (PET) using 18F-flurodeoxyglucose (FDG) to investigate glucose metabolism in brain and 18F-vesicle monoamine transporter 2 (VMAT2) to inspect the integrity of the dopaminergic neuron. Seventy-two healthy individuals were recruited as controls in the quantitative FDG-PET analysis. Imaging parameters were compared between symptomatic and presymptomatic cases with different disease durations. RESULTS: Patients displayed prominent action tremor, moderate ataxia, and subtle parkinsonism with poor levodopa-response. MRI showed extensive but heterogeneous cerebral atrophy, which was most evident in the frontoparietal lobes. Cerebellar atrophy was apparent in later stages. DKI detected impaired fibers in the cerebellar peduncles. In both symptomatic and pre-symptomatic cases, PET-CT showed an earlier FDG decline than atrophic changes in multiple regions, and the frontoparietal lobes were the earliest and most severe. However, the VMAT2 density were normal in the putamen and caudate nucleus of most cases (7/8). CONCLUSIONS: We first found that hypometabolism in the cerebral cortex, but not cerebellum, is an early and prominent change in SCA12. The integrity of presynaptic dopaminergic neurons remains largely spared during the whole disease process.


Assuntos
Fluordesoxiglucose F18 , Ataxias Espinocerebelares , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Linhagem , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/metabolismo , Neuroimagem , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética/métodos , Atrofia , China
6.
J Neuroradiol ; 49(1): 66-72, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32540338

RESUMO

OBJECTIVE: To investigate structural and functional alterations in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) compared with healthy controls. METHODS: Twenty-seven patients with polysomnography-confirmed iRBD and 33 healthy subjects were recruited. All subjects underwent a 3-tesla structural and resting-state functional magnetic resonance imaging (fMRI) examination. Voxel-based morphometry (VBM) analysis was performed to assess grey matter alterations between groups. The amplitude of low-frequency fluctuations (ALFF) was calculated and then compared to measure differences in spontaneous brain activity. Correlations were performed to explore associations between imaging metrics and clinical characteristics in iRBD patients. RESULTS: Compared with healthy controls, patients with iRBD had decreased grey matter volume in the frontal, temporal, parietal, occipital cortices as well as increased grey matter volume in cerebellum posterior lobe, putamen, and thalamus. Patients with iRBD also exhibited increased ALFF values in the right parahippocampal gyrus. Olfaction correlated with ALFF value changes in occipital cortices. CONCLUSIONS: Patients with iRBD had widespread decreases of grey matter volume. Increases of grey matter volume in cerebellum, putamen, and thalamus may suggest a compensatory effect, while the altered ALFF values in parahippocampal gyrus and occipital cortices may play a role in the underlying process of neurodegeneration in this disorder.


Assuntos
Transtorno do Comportamento do Sono REM , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Tálamo
7.
Mov Disord ; 35(3): 478-485, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31846123

RESUMO

BACKGROUND: Idiopathic rapid eye movement sleep behavior disorder is an early sign of neurodegenerative disease. This study aimed to quantitatively evaluate iron content in idiopathic rapid eye movement sleep behavior disorder patients using quantitative susceptibility mapping and to examine the potential of this technique to identify the prodromal stage of α-synucleinopathies. METHODS: Twenty-five idiopathic rapid eye movement sleep behavior disorder patients, 32 Parkinson's disease patients, and 50 healthy controls underwent quantitative susceptibility mapping. The mean magnetic susceptibility values within the bilateral substantia nigra, globus pallidus, red nucleus, head of the caudate nucleus, and putamen were calculated and compared among groups. The relationships between the values and the clinical features of idiopathic rapid eye movement sleep behavior disorder and Parkinson's disease were measured using correlation analysis. RESULTS: Idiopathic rapid eye movement sleep behavior disorder patients had elevated iron in the bilateral substantia nigra compared with healthy controls. Parkinson's disease patients had increased iron in the bilateral substantia nigra, globus pallidus, and left red nucleus compared with healthy controls and had elevated iron levels in the bilateral substantia nigra compared with idiopathic rapid eye movement sleep behavior disorder patients. Mean magnetic susceptibility values were positively correlated with disease duration in the left substantia nigra in idiopathic rapid eye movement sleep behavior disorder patients. CONCLUSIONS: Quantitative susceptibility mapping can detect increased iron in the substantia nigra in idiopathic rapid eye movement sleep behavior disorder, which becomes more significant as the disorder progresses. This technique has the potential to be an early objective neuroimaging marker for detecting α-synucleinopathies. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Doenças Neurodegenerativas , Transtorno do Comportamento do Sono REM , Globo Pálido , Humanos , Ferro , Substância Negra
8.
BMC Womens Health ; 19(1): 31, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732650

RESUMO

BACKGROUND: Post-menopause vaginal haemorrhage is typically related to gynaecological malignancies. Bleeding from vaginal varices rarely occurs, especially in nonpregnant women. Moreover, nonpregnancy-related causes of vaginal varicosities include portal hypertension, especially that caused by liver cirrhosis, pelvic congestion syndrome and Klippel-Trenaunay syndrome or Parkes-Weber syndrome. Here, we report an unusual cause of nonpregnancy-associated vaginal variceal bleeding. CASE PRESENTATION: A 55-year-old postmenopausal woman presented in our outpatient department with complaints of recurrent bloody vaginal discharge. A group of varicose veins and several haemorrhagic spots were found on her vaginal wall during a vaginal speculum examination. Genital cancers were excluded by colposcopy and transvaginal ultrasonography; furthermore, a pelvic arteriovenous fistula was not found on a pelvic computed tomography (CT) scan. However, congenital varicosities and deep arteriovenous shunts were observed in her left leg on arterial angiography. Moreover, vaginal bleeding was improved after resolution of the underlying deep arteriovenous shunts in her left leg. Therefore, congenital arteriovenous shunts and elevated inferior vena cava pressure might be responsible for her recurrent vaginal varicose bleeding. CONCLUSION: Haemorrhage due to vaginal varices is easily detected with a vaginal speculum examination. However, diagnosis and treatment of the original disease are important after bleeding is controlled.


Assuntos
Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/tratamento farmacológico , Terapia de Reposição Hormonal , Síndrome de Klippel-Trenaunay-Weber/diagnóstico , Síndrome de Klippel-Trenaunay-Weber/terapia , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/tratamento farmacológico , Varizes Esofágicas e Gástricas/fisiopatologia , Feminino , Humanos , Síndrome de Klippel-Trenaunay-Weber/fisiopatologia , Pessoa de Meia-Idade , Pós-Menopausa , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Hemorragia Uterina/fisiopatologia
9.
Acta Biochim Biophys Sin (Shanghai) ; 51(8): 845-855, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31287492

RESUMO

Autoimmune ovarian disease (AOD) is considered to be a major cause of premature ovarian failure (POF). The immunomodulatory properties of human amniotic epithelial cells (hAECs) have been studied in many disease models. We previously reported that hAECs restored ovarian function in chemotherapy-induced POF mice, but the immunomodulatory mechanism of hAECs is still unclear. To investigate the effect of hAECs on recipient mice, especially on regulatory Treg cells, hAECs and hAEC-conditioned medium (hAEC-CM) were intravenously injected into AOD mice immunized with zona pellucida protein 3 peptides (pZP3). Ovarian function was evaluated through estrous cycle, hormone secretion, follicle development, and cell apoptosis analysis. Immune cells including CD3, CD4, CD8 and Treg cells in the spleens were tested by flow cytometry. To elucidate the effect of hAEC-CM on macrophage function, inflammation model in vitro was established in RAW264.7 cells induced by lipopolysaccharide (LPS). hAECs and hAEC-CM regulated estrous cycles, promoted follicle development, ameliorated cell apoptosis and fibrosis in ovaries of AOD mice. In addition, hAECs significantly reversed the decrease of pZP3-induced Treg cells in the spleens. In vitro, hAEC-CM significantly inhibited the inflammatory reaction induced by LPS in RAW264.7 cells via up-regulating the expression of M2 macrophage genes. Further study demonstrated that hAEC-secreted transforming growth factor-beta and macrophage inhibitory factor played important roles in the macrophage polarization and migration under inflammatory stimulation. Taken together, hAECs restored ovarian function by up-regulating Treg cells in the spleens and reduced the inflammatory reaction via modulating the activated macrophage function in a paracrine manner in the ovaries of AOD mice.


Assuntos
Âmnio/citologia , Doenças Autoimunes/terapia , Células Epiteliais/citologia , Doenças Ovarianas/terapia , Insuficiência Ovariana Primária/terapia , Animais , Apoptose , Movimento Celular , Meios de Cultivo Condicionados/química , Modelos Animais de Doenças , Feminino , Células da Granulosa/citologia , Humanos , Imuno-Histoquímica , Inflamação , Oxirredutases Intramoleculares/metabolismo , Lipopolissacarídeos/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Baço/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Glicoproteínas da Zona Pelúcida/metabolismo
10.
Acta Biochim Biophys Sin (Shanghai) ; 50(12): 1227-1235, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30395153

RESUMO

Epithelial ovarian cancer (EOC) is the most fatal gynecologic malignancy due to its late diagnosis and lack of curative therapy. The antimalaria compound artemisinin and its derivatives, such as artesunate (ART) and dihydroartemisinin (DHA), have proven to be potent anticancer drugs and act through various anticancer mechanisms. To identify novel targets of artemisinin derivatives in EOC cells, we investigated the effects of ART and DHA on SKOV3 and primary EOC cell growth via CCK-8 assay. Both ART and DHA inhibited EOC cell growth. A cell cycle distribution analysis showed that ART and DHA caused G2/M cell cycle arrest. Moreover, ART and DHA induced autophagy in EOC cells, whereas autophagy inhibitors reversed the cell growth inhibition and cell cycle arrest induced by ART and DHA. Western blot analysis showed that ART and DHA also suppressed the cell cycle-related NF-κB-signaling pathway in EOC cells. These data suggest that artemisinin derivatives induce autophagy, block the cell cycle, and inhibit cell growth in EOC cells. Our research provides new targets for artemisinin derivatives for EOC treatment.


Assuntos
Artemisininas/farmacologia , Artesunato/farmacologia , Autofagia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Antimaláricos/farmacologia , Autofagia/genética , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , NF-kappa B/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos
11.
BMC Plant Biol ; 17(1): 244, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29258440

RESUMO

BACKGROUND: During asexual reproduction the embryogenic callus can differentiate into a new plantlet, offering great potential for fostering in vitro culture efficiency in plants. The immature embryos (IMEs) of wheat (Triticum aestivum L.) are more easily able to generate embryogenic callus than mature embryos (MEs). To understand the molecular process of embryogenic callus formation in wheat, de novo transcriptome sequencing was used to generate transcriptome sequences from calli derived from IMEs and MEs after 3d, 6d, or 15d of culture (DC). RESULTS: In total, 155 million high quality paired-end reads were obtained from the 6 cDNA libraries. Our de novo assembly generated 142,221 unigenes, of which 59,976 (42.17%) were annotated with a significant Blastx against nr, Pfam, Swissprot, KOG, KEGG, GO and COG/KOG databases. Comparative transcriptome analysis indicated that a total of 5194 differentially expressed genes (DEGs) were identified in the comparisons of IME vs. ME at the three stages, including 3181, 2085 and 1468 DEGs at 3, 6 and 15 DC, respectively. Of them, 283 overlapped in all the three comparisons. Furthermore, 4731 DEGs were identified in the comparisons between stages in IMEs and MEs. Functional analysis revealed that 271transcription factor (TF) genes (10 overlapped in all 3 comparisons of IME vs. ME) and 346 somatic embryogenesis related genes (SSEGs; 35 overlapped in all 3 comparisons of IME vs. ME) were differentially expressed in at least one comparison of IME vs. ME. In addition, of the 283 overlapped DEGs in the 3 comparisons of IME vs. ME, excluding the SSEGs and TFs, 39 possessed a higher rate of involvement in biological processes relating to response to stimuli, in multi-organism processes, reproductive processes and reproduction. Furthermore, 7 were simultaneously differentially expressed in the 2 comparisons between the stages in IMEs, but not MEs, suggesting that they may be related to embryogenic callus formation. The expression levels of genes, which were validated by qRT-PCR, showed a high correlation with the RNA-seq value. CONCLUSIONS: This study provides new insights into the role of the transcriptome in embryogenic callus formation in wheat, and will serve as a valuable resource for further studies addressing embryogenic callus formation in plants.


Assuntos
Proteínas de Plantas/genética , Transcriptoma/genética , Triticum/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Células do Mesofilo/metabolismo , Proteínas de Plantas/metabolismo , Sementes/embriologia , Sementes/genética , Triticum/embriologia
12.
Reprod Biol Endocrinol ; 15(1): 38, 2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28499456

RESUMO

Premature ovarian insufficiency (POI) is a typical disorder of amenorrhea lasting for a minimum of 4 months. The typical characteristics comprised of declined estrogen and raised serum concentrations of follicle-stimulating hormone (FSH) in women <40-year-old, primarily originating from iatrogenic factors, karyotypic abnormalities, and genetic factors. However, the etiology of POI remains unknown in approximately 90% of cases. POI could lead to infertility, osteoporosis, cardiovascular disorder, and cognitive dysfunction. MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs (ncRNAs) that can mediate post-translational silencing of the genes involved in the regulation of proliferation, differentiation, apoptosis, development, tumorigenesis, and hematopoiesis. Recently, the regulatory functions of miRNAs in the development of POI have been the topic of intensive research. The present review addresses the association of miRNAs' machinery genes (Dicer, Drosha, and XPO5) with POI and the miRNA expression profiles in the plasma of patients with POI. In addition, several specific miRNAs (miR-23a, miR-27a, miR-22-3p, miR-146a, miR-196a, miR-290-295, miR-423, and miR-608) related to POI are also examined in order to highlight the issues that deserve further investigation. A thorough understanding of the exact regulatory roles of miRNAs is imperative to gain novel insights into the etiology of idiopathic POI and offer new research directions in the field.


Assuntos
MicroRNAs/fisiologia , Insuficiência Ovariana Primária/genética , Adulto , Amenorreia/genética , Feminino , Humanos , Pessoa de Meia-Idade
13.
Int J Biometeorol ; 58(7): 1521-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24162181

RESUMO

In this paper, we analyze the relationships among the tree-ring chronology, meteorological drought (precipitation), agricultural drought (Palmer Drought Severity Index PDSI), hydrological drought (runoff), and agricultural data in the Shanxi province of North China. Correlation analyses indicate that the tree-ring chronology is significantly correlated with all of the drought indices during the main growing season from March to July. Sign test analyses further indicate that the tree-ring chronology shows variation similar to that of the drought indices in both high and low frequencies. Comparisons of the years with narrow tree rings to the severe droughts reflected in all three indices from 1957 to 2008 reveal that the radial growth of the trees in the study region can accurately record the severe drought for which all three indices were in agreement (1972, 1999, 2000, and 2001). Comparisons with the dryness/wetness index indicate that tree-ring growth can properly record the severe droughts in the history. Correlation analyses among agricultural data, tree-ring chronology, and drought indices indicate that the per-unit yield of summer crops is relatively well correlated with the agricultural drought, as indicated by the PDSI. The PDSI is the climatic factor that significantly influences both tree growth and per-unit yield of summer crops in the study region. These results indicate that the PDSI and tree-ring chronology have the potential to be used to monitor and predict the yield of summer crops. Tree-ring chronology is an important tool for drought research and for wider applications in agricultural and hydrological research.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Secas , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento , China , Chuva
14.
Sci Rep ; 14(1): 10621, 2024 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-38729969

RESUMO

Asymptomatic Leucine-Rich Repeat Kinase 2 Gene (LRRK2) carriers are at risk for developing Parkinson's disease (PD). We studied presymptomatic substantia nigra pars compacta (SNc) regional neurodegeneration in asymptomatic LRRK2 carriers compared to idiopathic PD patients using neuromelanin-sensitive MRI technique (NM-MRI). Fifteen asymptomatic LRRK2 carriers, 22 idiopathic PD patients, and 30 healthy controls (HCs) were scanned using NM-MRI. We computed volume and contrast-to-noise ratio (CNR) derived from the whole SNc and the sensorimotor, associative, and limbic SNc regions. An analysis of covariance was performed to explore the differences of whole and regional NM-MRI values among the groups while controlling the effect of age and sex. In whole SNc, LRRK2 had significantly lower CNR than HCs but non-significantly higher volume and CNR than PD patients, and PD patients significantly lower volume and CNR compared to HCs. Inside SNc regions, there were significant group effects for CNR in all regions and for volumes in the associative region, with a trend in the sensorimotor region but no significant changes in the limbic region. PD had reduced volume and CNR in all regions compared to HCs. Asymptomatic LRRK2 carriers showed globally decreased SNc volume and CNR suggesting early nigral neurodegeneration in these subjects at risk of developing PD.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Imageamento por Ressonância Magnética , Melaninas , Doença de Parkinson , Substância Negra , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Melaninas/metabolismo , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/genética , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Doença de Parkinson/metabolismo , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Substância Negra/metabolismo , Idoso , Heterozigoto , Adulto , Estudos de Casos e Controles
15.
NPJ Parkinsons Dis ; 10(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172178

RESUMO

REM sleep behavior disorder (RBD) symptoms in Parkinson's disease (PD) suggest both a clinically and pathologically malignant subtype. However, whether RBD symptoms are associated with alterations in the organization of whole-brain intrinsic functional networks in PD, especially at early disease stages, remains unclear. Here we use resting-state functional MRI, coupled with graph-theoretical approaches and network-based statistics analyses, and validated with large-scale network analyses, to characterize functional brain networks and their relationship with clinical measures in early PD patients with probable RBD (PD+pRBD), early PD patients without probable RBD (PD-pRBD) and healthy controls. Thirty-six PD+pRBD, 57 PD-pRBD and 71 healthy controls were included in the final analyses. The PD+pRBD group demonstrated decreased global efficiency (t = -2.036, P = 0.0432) compared to PD-pRBD, and decreased network efficiency, as well as comprehensively disrupted nodal efficiency and whole-brain networks (all eight networks, but especially in the sensorimotor, default mode and visual networks) compared to healthy controls. The PD-pRBD group showed decreased nodal degree in right ventral frontal cortex and more affected edges in the frontoparietal and ventral attention networks compared to healthy controls. Furthermore, the assortativity coefficient was negatively correlated with Montreal cognitive assessment scores in the PD+pRBD group (r = -0.365, P = 0.026, d = 0.154). The observation of altered whole-brain functional networks and its correlation with cognitive function in PD+pRBD suggest reorganization of the intrinsic functional connectivity to maintain the brain function in the early stage of the disease. Future longitudinal studies following these alterations along disease progression are warranted.

16.
Int J Biometeorol ; 57(6): 927-34, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23274859

RESUMO

Precipitation from the previous August to the current June over the last 232 years in Liancheng, China, was reconstructed by a transfer function based on the correlation between tree-ring widths and local meteorological data. The explained variance was 45.3 %, and fluctuations on both annual and decadal scales were captured. Wet periods with precipitation above the 232-year mean occurred from 1777 to 1785, 1802 to 1818, 1844 to 1861, 1889 to 1922 and 1939 to 1960. Dry periods (precipitation below the mean) occurred from 1786 to 1801, 1819 to 1843, 1862 to 1888 and 1923 to 1938. The reconstruction compares well with a tree-ring-based precipitation reconstruction at Mt. Xinglong; both of them showed the well-known severe drought in the late 1920s. The rainfall series also shows highly synchronous decreasing trends since the 1940s, suggesting that precipitation related to the East Asian summer monsoon at these two sites has decreased by large spatial and temporal (decadal) scales. Power spectrum analysis of the reconstruction showed remarkable 21.82-, 3.48-, 3.12-, 3.08- and 2.31-year cycles for the past 232 years; the 22-year cycle corresponds to the solar cycle and is expressed widely in tree ring/precipitation reconstructions on the China Loess Plateau. This may suggest a solar influence on the precipitation variations on the Loess Plateau, although the mechanisms are not well understood.


Assuntos
Modelos Estatísticos , Pinus/citologia , Pinus/crescimento & desenvolvimento , Caules de Planta/citologia , Caules de Planta/crescimento & desenvolvimento , Chuva , Estações do Ano , Madeira/análise , China , Simulação por Computador
17.
Int J Gynaecol Obstet ; 161(1): 93-99, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36226665

RESUMO

OBJECTIVE: To compare the effects of barbed suture (BS) and conventional suture (CS) on perioperative conditions and ovarian function in the excision of ovarian mature cystic teratoma (MCT) by laparo-endoscopic single-site surgery (LESS). METHODS: The present study is an ambispective cohort study conducted in an affiliated tertiary hospital between May 2019 and October 2020. Women treated by LESS cystectomy for unilateral ovarian MCT were included. BS or CS were applied in the surgery. RESULTS: BS and CS groups were matched 1:1 for age, body mass index and ovarian cyst volume (40 women per group). There were no significant differences in baseline characteristics. Mean operating time (53.89 ± 14.80 versuss 67.93 ± 19.23 min, P = 0.004) and suturing time (11.85 ± 6.68 versus 19.76 ± 12.75 min, P = 0.006) were significantly shorter in the BS group than the CS group. No significant differences were found in serum anti-Müllerian hormone (AMH) levels between groups at baseline, postoperative day 1, 3 months, and 12 months. However, serum AMH was significantly lower than baseline at postoperative day 1, 3 months, and 12 months in both groups. CONCLUSION: BS provides shorter operating and suturing time than CS, without increasing damage to ovarian function in LESS cystectomy for ovarian MCT.


Assuntos
Endometriose , Laparoscopia , Cistos Ovarianos , Reserva Ovariana , Teratoma , Feminino , Humanos , Estudos de Coortes , Cistectomia , Endometriose/cirurgia , Estudos Prospectivos , Cistos Ovarianos/cirurgia , Teratoma/cirurgia , Suturas , Hormônio Antimülleriano
18.
Front Aging Neurosci ; 15: 1187684, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448687

RESUMO

Introduction: The ventral tegmental area (VTA) is less affected compared to substantia nigra pars compacta (SNc) in Parkinson's disease (PD). This study aimed to quantitatively evaluate iron content in the VTA across different stages of PD in order to help explain the selective loss of dopamine neurons in PD. Methods: Quantitative susceptibility mapping (QSM) data were obtained from 101 PD patients, 35 idiopathic rapid eye movement sleep behavior disorder (RBD) patients, and 62 healthy controls (HCs). The mean QSM values in the VTA and SNc were calculated and compared among the groups. Results: Both RBD and PD patients had increased iron values in the bilateral SNc compared with HCs. RBD and PD patients in the Hoehn-Yahr (H & Y) stage 1 did not show elevated iron values in the VTA, while PD patients with more than 1.5 H & Y staging had increased iron values in bilateral VTA compared to HCs. Discussion: This study shows that there is no increased iron accumulation in the VTA during the prodromal and early clinical stages of PD, but iron deposition increases significantly as the disease becomes more severe.

19.
Front Med (Lausanne) ; 10: 1275605, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259854

RESUMO

Purpose: To determine the 90 percent effective dose (ED90) of intrathecal sufentanil combined with ropivacaine 2.5 mg for labor analgesia and observe its safety for parturients and neonates. Methods: We conducted a prospective, double-blind, biased coin up-and-down study. We injected a fixed 2.5 mg ropivacaine combined with a designated dose of sufentanil intrathecally to observe the labor analgesic effect. The initial dose of sufentanil was assigned 1.0 µg, and the remaining doses were assigned as per the biased coin up-and-down method. The criterion of successful response was defined as VAS ≤ 30 mm after intrathecal injection at 10 min. Safety was evaluated in terms of maternal and neonatal outcomes. Results: The ED90 dose of intrathecal sufentanil combined with ropivacaine 2.5 mg (0.1%, 2.5 mL) was 2.61 µg (95% CI, 2.44 to 2.70 µg) by isotonic regression. No respiratory depression, hypotension, or motor block was observed. Thirty-one (77.5%) parturients complained of pruritus, and 14 (35.0%) suffered nausea and vomiting. Three neonates reported a 1 min Apgar score of ≤7, and none reported a 5 min Apgar score of ≤7. Conclusion: The ED90 of intrathecal sufentanil combined with ropivacaine 2.5 mg for labor analgesia was 2.61 µg. The dose is safe for parturients and neonates.

20.
NPJ Parkinsons Dis ; 9(1): 28, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36806219

RESUMO

Neuroimaging studies suggest a pivotal role of amygdala dysfunction in non-motor symptoms (NMS) of Parkinson's disease (PD). However, the relationship between amygdala subregions (the centromedial (CMA), basolateral (BLA) and superficial amygdala (SFA)) and NMS has not been delineated. We used resting-state functional MRI to examine the PD-related alterations in functional connectivity for amygdala subregions. The left three subregions and right BLA exhibited between-group differences, and were commonly hypo-connected with the frontal, temporal, insular cortex, and putamen in PD. Each subregion displayed distinct hypoconnectivity with the limbic systems. Partial least-squares analysis revealed distinct amygdala subregional involvement in diverse NMS. Hypo-connectivity of all four subregions was associated with emotion, pain, olfaction, and cognition. Hypo-connectivity of the left SFA was associated with sleepiness. Our findings highlight the hypofunction of the amygdala subregions in PD and their preliminary associations with NMS, providing new insights into the pathogenesis of NMS.

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