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1.
Hum Reprod ; 38(4): 686-700, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36762771

RESUMO

STUDY QUESTION: Which substances and signal transduction pathways are potentially active downstream to the effect of FSH and LH in the regulation of human oocyte maturation in vivo? SUMMARY ANSWER: The regulation of human oocyte maturation appears to be a multifactorial process in which several different signal transduction pathways are active. WHAT IS KNOWN ALREADY: Many studies in animal species have provided insight into the mechanisms that govern the final maturation of oocytes. Currently, these studies have identified several different mechanisms downstream to the effects of FSH and LH. Some of the identified mechanisms include the regulation of cAMP/cGMP levels in oocytes involving C-type natriuretic peptide (CNP), effects of epidermal growth factor (EGF)-related peptides such as amphiregulin (AREG) and/or epiregulin (EREG), effect of TGF-ß family members including growth differentiation factor 9 (GDF9) and morphogenetic protein 15 (BMP15), activins/inhibins, follicular fluid meiosis activating sterol (FF-MAS), the growth factor midkine (MDK), and several others. However, to what extent these pathways and mechanisms are active in humans in vivo is unknown. STUDY DESIGN, SIZE, DURATION: This prospective cohort study included 50 women undergoing fertility treatment in a standard antagonist protocol at a university hospital affiliated fertility clinic in 2016-2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: We evaluated the substances and signalling pathways potentially affecting human oocyte maturation in follicular fluid (FF) and granulosa cells (GCs) collected at five time points during the final maturation of follicles. Using ELISA measurement and proteomic profiling of FF and whole genome gene expression in GC, the following substances and their signal transduction pathways were collectively evaluated: CNP, the EGF family, inhibin-A, inhibin-B, activins, FF-MAS, MDK, GDF9, and BMP15. MAIN RESULTS AND THE ROLE OF CHANCE: All the evaluated substances and signal transduction pathways are potentially active in the regulation of human oocyte maturation in vivo except for GDF9/BMP15 signalling. In particular, AREG, inhibins, and MDK were significantly upregulated during the first 12-17 h after initiating the final maturation of follicles and were measured at significantly higher concentrations than previously reported. Additionally, the genes regulating FF-MAS synthesis and metabolism were significantly controlled in favour of accumulation during the first 12-17 h. In contrast, concentrations of CNP were low and did not change during the process of final maturation of follicles, and concentrations of GDF9 and BMP15 were much lower than reported in small antral follicles, suggesting a less pronounced influence from these substances. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: Although GC and cumulus cells have many similar features, it is a limitation of the current study that information for the corresponding cumulus cells is not available. However, we seldom recovered a cumulus-oocyte complex during the follicle aspiration from 0 to 32 h. WIDER IMPLICATIONS OF THE FINDINGS: Delineating the mechanisms governing the regulation of human oocyte maturation in vivo advances the possibility of developing a platform for IVM that, as for most other mammalian species, results in healthy offspring with good efficacy. Mimicking the intrafollicular conditions during oocyte maturation in vivo in small culture droplets during IVM may enhance oocyte nuclear and cytoplasmic maturation. The primary outlook for such a method is, in the context of fertility preservation, to augment the chances of achieving biological children after a cancer treatment by subjecting oocytes from small antral follicles to IVM. Provided that aspiration of oocytes from small antral follicles in vivo can be developed with good efficacy, IVM may be applied to infertile patients on a larger scale and can provide a cheap alternative to conventional IVF treatment with ovarian stimulation. Successful IVM has the potential to change current established techniques for infertility treatment. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the University Hospital of Copenhagen, Rigshospitalet, the Independent Research Fund Denmark (grant number 0134-00448), and the Interregional EU-sponsored ReproUnion network. There are no conflicts of interest to be declared.


Assuntos
Fator de Crescimento Epidérmico , Proteômica , Animais , Criança , Humanos , Feminino , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Estudos Prospectivos , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/metabolismo , Peptídeo Natriurético Tipo C/farmacologia , Hormônio Foliculoestimulante/metabolismo , Inibinas/metabolismo , Ativinas/metabolismo , Mamíferos
2.
ESMO Open ; 8(1): 100741, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36527824

RESUMO

BACKGROUND: Brain metastases are associated with considerable negative effects on patients' outcome in lung adenocarcinoma (LADC). Here, we investigated the proteomic landscape of primary LADCs and their corresponding brain metastases. MATERIALS AND METHODS: Proteomic profiling was conducted on 20 surgically resected primary and brain metastatic LADC samples via label-free shotgun proteomics. After sample processing, peptides were analyzed using an Ultimate 3000 pump coupled to a QExactive HF-X mass spectrometer. Raw data were searched using PD 2.4. Further data analyses were carried out using Perseus, RStudio and GraphPad Prism. Proteomic data were correlated with clinical and histopathological parameters and the timing of brain metastases. Mass spectrometry-based proteomic data are available via ProteomeXchange with identifier PXD027259. RESULTS: Out of the 6821 proteins identified and quantified, 1496 proteins were differentially expressed between primary LADCs and corresponding brain metastases. Pathways associated with the immune system, cell-cell/matrix interactions and migration were predominantly activated in the primary tumors, whereas pathways related to metabolism, translation or vesicle formation were overrepresented in the metastatic tumors. When comparing fast- versus slow-progressing patients, we found 454 and 298 differentially expressed proteins in the primary tumors and brain metastases, respectively. Metabolic reprogramming and ribosomal activity were prominently up-regulated in the fast-progressing patients (versus slow-progressing individuals), whereas expression of cell-cell interaction- and immune system-related pathways was reduced in these patients and in those with multiple brain metastases. CONCLUSIONS: This is the first comprehensive proteomic analysis of paired primary tumors and brain metastases of LADC patients. Our data suggest a malfunction of cellular attachment and an increase in ribosomal activity in LADC tissue, promoting brain metastasis. The current study provides insights into the biology of LADC brain metastases and, moreover, might contribute to the development of personalized follow-up strategies in LADC.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Encefálicas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Proteômica , Biomarcadores Tumorais , Neoplasias Encefálicas/secundário , Encéfalo/metabolismo , Encéfalo/patologia
3.
Compr Psychoneuroendocrinol ; 10: 100126, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35755210

RESUMO

Objectives: The aims of the study are i) to compare 25-hydroxyvitamin D (25(OH)D) levels between clinically depressed individuals with insufficient treatment response and healthy controls and ii) to test the association between 25(OH)D levels and different affective disorder diagnoses (i.e., major depressive disorder (MDD) single episode, MDD recurrent episode, chronic MDD, and dysthymia), as well as grade of suicidal ideation. Method: We quantified serum 25(OH)D in 202 individuals with difficult-to-treat depression (DTD) and 41 healthy controls. Patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV-TR). ANCOVA was used to test differences in mean 25(OH)levels between depressed and controls, adjusting for sex, age, smoking, sampling season, ethnicity, somatic illness, and body mass index (BMI). Binary logistic regression models were used to test the association between depression and 25(OH)D levels. Results: Patients with difficult-to-treat depression had significantly lower levels of 25(OH)D compared to healthy controls (ANCOVA, F = 4.89; p = 0.03). Thirty percent of the depressed patients were 25(OH)D deficient (<50 nmol/L) compared to 5% of the controls (Chi-squared test, χ2 = 11.38; p < 0.01). The odds for being depressed decreased significantly with 17% per 10 nmol/L increase of 25(OH)D (Binary logistic regression, p < 0.05). Limitations: The cross-sectional design of the study precludes any conclusions about causality. A large part of the patients took psychotropic drugs and/or had somatic illnesses, which might have affected the results. Conclusion: The results of the present study add to the body of evidence linking 25(OH)D deficiency and depression. Further investigations are warranted to better understand any clinical implications of this association.

4.
AJNR Am J Neuroradiol ; 42(7): 1201-1207, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33888457

RESUMO

BACKGROUND AND PURPOSE: Systematic analysis of angulation-related variability of idiopathic normal pressure hydrocephalus imaging biomarkers has not been published yet. Our aim was to evaluate the variability of these radiologic biomarkers with respect to imaging plane angulation. MATERIALS AND METHODS: Eighty subjects (35 with clinically confirmed idiopathic normal pressure hydrocephalus and 45 age- and sex-matched healthy controls) were prospectively enrolled in a 3T brain MR imaging study. Two independent readers assessed 12 radiologic idiopathic normal pressure hydrocephalus biomarkers on sections aligned parallel or perpendicular to the bicallosal, bicommissural, hypophysis-fastigium, and brain stem vertical lines, respectively. RESULTS: Disproportionately enlarged subarachnoid space hydrocephalus, simplified callosal angle, frontal horn diameter, z-Evans Index, and cella media vertical width did not show significant systematic differences in any of 6 section plane combinations studied. The remaining 7 biomarkers (including the Evans Index and callosal angle) showed significant differences in up to 4 of 6 mutually compared section plane combinations. The values obtained from sections aligned with the brain stem vertical line (parallel to the posterior brain stem margin) showed the most deviating results from other section angulations. CONCLUSIONS: Seven of 12 idiopathic normal pressure hydrocephalus biomarkers including the frequently used Evans Index and callosal angle showed statistically significant deviations when measured on sections whose angulations differed or did not comply with the proper section definition published in the original literature. Strict adherence to the methodology of idiopathic normal pressure hydrocephalus biomarker assessment is, therefore, essential to avoid an incorrect diagnosis. Increased radiologic and clinical attention should be paid to the biomarkers showing low angulation-related variability yet high specificity for idiopathic normal pressure hydrocephalus-related morphologic changes such as the z-Evans Index, frontal horn diameter, or disproportionately enlarged subarachnoid space hydrocephalus.


Assuntos
Encéfalo/diagnóstico por imagem , Hidrocefalia de Pressão Normal , Imageamento por Ressonância Magnética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos Transversais , Feminino , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Reprodutibilidade dos Testes
5.
AJNR Am J Neuroradiol ; 42(5): 927-929, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33707277

RESUMO

Carotid near-occlusion is a frequently overlooked diagnosis when CTA examinations are assessed in routine practice. To evaluate the potential value of phase-contrast MR imaging in identifying near-occlusion, we examined 9 carotid near-occlusions and 20 cases of conventional ≥50% carotid stenosis (mean stenosis degree, 65%) with phase-contrast MR imaging. Mean ICA flow was lower in near-occlusions (52 mL/min) than in conventional ≥50% stenosis (198 mL/min, P < .001). ICA flow of ≤110 mL/min was 100% sensitive and specific for near-occlusion. Phase-contrast MR imaging is a promising tool for diagnosing carotid near-occlusion.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Fluids Barriers CNS ; 16(1): 40, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31865917

RESUMO

BACKGROUND: Communicating hydrocephalus is a disease where the cerebral ventricles are enlarged. It is characterized by the absence of detectable cerebrospinal fluid (CSF) outflow obstructions and often with increased CSF pulsatility measured in the cerebral aqueduct (CA). We hypothesize that the cardiac-related pulsatile flow over the CA, with fast systolic outflow and slow diastolic inflow, can generate net pressure effects that could source the ventriculomegaly in these patients. This would require a non-zero cardiac cycle averaged net pressure difference (ΔPnet) over the CA, with higher average pressure in the lateral and third ventricles. METHODS: We tested the hypothesis by calculating ΔPnet across the CA using computational fluid dynamics based on prospectively collected high-resolution structural (FIESTA-C, resolution 0.39 × 0.39 × 0.3 mm3) and velocimetric (2D-PCMRI, in-plane resolution 0.35 × 0.35 mm2) MRI-data from 30 patients investigated for communicating hydrocephalus. RESULTS: The ΔPnet due to CSF pulsations was non-zero for the study group (p = 0.03) with a magnitude of 0.2 ± 0.4 Pa (0.001 ± 0.003 mmHg), with higher pressure in the third ventricle. The maximum pressure difference over the cardiac cycle ΔPmax was 20.3 ± 11.8 Pa and occurred during systole. A generalized linear model verified an association between ΔPnet and CA cross-sectional area (p = 0.01) and flow asymmetry, described by the ratio of maximum inflow/outflow (p = 0.04), but not for aqueductal stroke volume (p = 0.35). CONCLUSIONS: The results supported the hypothesis with respect to the direction of ΔPnet, although the magnitude was low. Thus, although the pulsations may generate a pressure difference across the CA it is likely too small to explain the ventriculomegaly in communicating hydrocephalus.


Assuntos
Aqueduto do Mesencéfalo/fisiopatologia , Hidrocefalia/líquido cefalorraquidiano , Hidrocefalia/fisiopatologia , Fluxo Pulsátil , Idoso , Idoso de 80 Anos ou mais , Aqueduto do Mesencéfalo/diagnóstico por imagem , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Estudos Prospectivos
7.
Acta Neurol Scand ; 138(4): 284-292, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29770439

RESUMO

OBJECTIVES: A third of patients with stroke acquire spatial neglect associated with poor rehabilitation outcome. New effective rehabilitation interventions are needed. Scanning training combined with multisensory stimulation to enhance the rehabilitation effect is suggested. In accordance, we have designed a virtual-reality based scanning training that combines visual, audio and sensori-motor stimulation called RehAtt® . Effects were shown in behavioural tests and activity of daily living. Here, we use fMRI to evaluate the change in brain activity during Posner's Cuing Task (attention task) after RehAtt® intervention, in patients with chronic neglect. METHODS: Twelve patients (mean age = 72.7 years, SD = 6.1) with chronic neglect (persistent symptoms >6 months) performed the interventions 3 times/wk during 5 weeks, in total 15 hours. Training effects on brain activity were evaluated using fMRI task-evoked responses during the Posner's cuing task before and after the intervention. RESULTS: Patients improved their performance in the Posner fMRI task. In addition, patients increased their task-evoked brain activity after the VR interventions in an extended network including pre-frontal and temporal cortex during attentional cueing, but showed no training effects during target presentations. CONCLUSIONS: The current pilot study demonstrates that a novel multisensory VR intervention has the potential to benefit patients with chronic neglect in respect of behaviour and brain changes. Specifically, the fMRI results show that strategic processes (top-down control during attentional cuing) were enhanced by the intervention. The findings increase knowledge of the plasticity processes underlying positive rehabilitation effects from RehAtt® in chronic neglect.


Assuntos
Lobo Frontal/diagnóstico por imagem , Transtornos da Percepção/diagnóstico por imagem , Transtornos da Percepção/reabilitação , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Terapia de Exposição à Realidade Virtual/métodos , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Feminino , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/etiologia , Projetos Piloto , Distribuição Aleatória , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/tendências , Resultado do Tratamento , Terapia de Exposição à Realidade Virtual/tendências
8.
Am J Physiol Regul Integr Comp Physiol ; 314(3): R377-R385, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29118021

RESUMO

Recent interest in intracranial pressure (ICP) in the upright posture has revealed that the mechanisms regulating postural changes in ICP are not fully understood. We have suggested an explanatory model where the postural changes in ICP depend on well-established hydrostatic effects in the venous system and where these effects are interrupted by collapse of the internal jugular veins (IJVs) in more upright positions. The aim of this study was to investigate this relationship by simultaneous invasive measurements of ICP, venous pressure, and IJV collapse in healthy volunteers. ICP (monitored via the lumbar route), central venous pressure (peripherally inserted central catheter line), and IJV cross-sectional area (ultrasound) were measured in 11 healthy volunteers (47 ± 10 yr, mean ± SD) in 7 positions, from supine to sitting (0-69°). Venous pressure and anatomical distances were used to predict ICP in accordance with the explanatory model, and IJV area was used to assess IJV collapse. The hypothesis was tested by comparing measured ICP with predicted ICP. Our model accurately described the general behavior of the observed postural ICP changes (mean difference, -0.03 ± 2.7 mmHg). No difference was found between predicted and measured ICP for any tilt angle ( P values, 0.65-0.94). The results support the hypothesis that postural ICP changes are governed by hydrostatic effects in the venous system and IJV collapse. This improved understanding of postural ICP regulation may have important implications for the development of better treatments for neurological and neurosurgical conditions affecting ICP.


Assuntos
Pressão Intracraniana , Veias Jugulares/fisiologia , Postura , Pressão Venosa , Adaptação Fisiológica , Adulto , Feminino , Voluntários Saudáveis , Humanos , Pressão Hidrostática , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Postura Sentada , Decúbito Dorsal , Teste da Mesa Inclinada , Fatores de Tempo
9.
Acta Neurol Scand ; 135(5): 576-584, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27388230

RESUMO

OBJECTIVES: Increased aqueduct cerebrospinal fluid (CSF) flow pulsatility and, recently, a reversed CSF flow in the aqueduct have been suggested as hallmarks of idiopathic normal pressure hydrocephalus (INPH). However, these findings have not been adequately confirmed. Our objective was to investigate the flow of blood and CSF in INPH, as compared to healthy elderly, in order to clarify which flow parameters are related to the INPH pathophysiology. MATERIALS AND METHODS: Sixteen INPH patients (73 years) and 35 healthy subjects (72 years) underwent phase-contrast magnetic resonance imaging (MRI). Measurements included aqueduct and cervical CSF flow, total arterial inflow (tCBF; i.e. carotid + vertebral arteries), and internal jugular vein flow. Flow pulsatility, net flow, and flow delays were compared (multiple linear regression, correcting for sex and age). RESULTS: Aqueduct stroke volume was higher in INPH than healthy (148±95 vs 90±50 mL, P<.05). Net aqueduct CSF flow was similar in magnitude and direction. The cervical CSF stroke volume was lower (P<.05). The internal carotid artery net flow was lower in INPH (P<.05), although tCBF was not. No differences were found in internal jugular vein flow or flow delays. CONCLUSIONS: The typical flow of blood and CSF in INPH was mainly characterized by increased CSF pulsatility in the aqueduct and reduced cervical CSF pulsatility. The direction of mean net aqueduct CSF flow was from the third to the fourth ventricle. Our findings may reflect the altered distribution of intracranial CSF volume in INPH, although the causality of these relationships is unclear.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Aqueduto do Mesencéfalo/diagnóstico por imagem , Aqueduto do Mesencéfalo/fisiologia , Líquido Cefalorraquidiano/fisiologia , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Ventrículos Cerebrais/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil/fisiologia , Estudos Retrospectivos , Método Simples-Cego
10.
Breast ; 28: 184-90, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27326980

RESUMO

BACKGROUND: Previous studies regarding the association between serum 25-hydroxyvitamin D (25OHD3) and breast cancer risk have not been conclusive. The aim of this study was to investigate the potential association between pre-diagnostic serum 25OHD3 levels and the risk of different subtypes of breast cancer. MATERIALS AND METHODS: The study was based on The Malmö Diet and Cancer Study recruiting 17,035 women from 1991 to 1996. A total of 764 incident breast cancers with matched controls were analysed for 25OHD3 in samples collected at baseline, before diagnosis. A logistic regression analysis was used to calculate odds ratios with 95% confidence intervals for tertiles of 25OHD3 in relation to different subtypes of breast cancer, i.e. defined according to tumour type, tumour size, lymph node involvement, histological grade, oestrogen receptor (ER) status, progesterone receptor (PgR) status, Ki67, cyclin D1 and p27. RESULTS: As compared to the 1st tertile of 25OHD3, the second tertile had a statistically significantly lower risk of ER negative tumours, PgR negative tumours and tumours with a high expression of Ki67, A similar pattern was seen in relation to large tumours (≥21 mm), grade III tumours, and tumours with low p27 expression, but these associations did not reach statistical significance. The third tertile had a similar risk as the first tertile. CONCLUSIONS: We found that women with low levels of 25OHD3, as compare to women in the middle tertile, had a high risk of breast tumours with an unfavourable prognosis.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/patologia , Calcifediol/sangue , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Ciclina D1/análise , Inibidor de Quinase Dependente de Ciclina p27/análise , Feminino , Humanos , Antígeno Ki-67/análise , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Fatores de Risco , Carga Tumoral
11.
AJNR Am J Neuroradiol ; 36(10): 1816-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26251434

RESUMO

BACKGROUND AND PURPOSE: The arterial spin-labeling method for CBF assessment is widely available, but its accuracy is not fully established. We investigated the accuracy of a whole-brain arterial spin-labeling technique for assessing the mean parenchymal CBF and the effect of aging in healthy volunteers. Phase-contrast MR imaging was used as the reference method. MATERIALS AND METHODS: Ninety-two healthy volunteers were included: 49 young (age range, 20-30 years) and 43 elderly (age range, 65-80 years). Arterial spin-labeling parenchymal CBF values were averaged over the whole brain to quantify the mean pCBF(ASL) value. Total CBF was assessed with phase-contrast MR imaging as the sum of flows in the internal carotid and vertebral arteries, and subsequent division by brain volume returned the pCBF(PCMRI) value. Accuracy was considered as good as that of the reference method if the systematic difference was less than 5 mL/min/100 g of brain tissue and if the 95% confidence intervals were equal to or better than ±10 mL/min/100 g. RESULTS: pCBF(ASL) correlated to pCBF(PCMRI) (r = 0.73; P < .001). Significant differences were observed between the pCBF(ASL) and pCBF(PCMRI) values in the young (P = .001) and the elderly (P < .001) volunteers. The systematic differences (mean ± 2 standard deviations) were -4 ± 14 mL/min/100 g in the young subjects and 6 ± 12 mL/min/100 g in the elderly subjects. Young subjects showed higher values than the elderly subjects for pCBF(PCMRI) (young, 57 ± 8 mL/min/100 g; elderly, 54 ± 7 mL/min/100 g; P = .05) and pCBF(ASL) (young, 61 ± 10 mL/min/100 g; elderly, 48 ± 10 mL/min/100 g; P < .001). CONCLUSIONS: The limits of agreement were too wide for the arterial spin-labeling method to be considered satisfactorily accurate, whereas the systematic overestimation in the young subjects and underestimation in the elderly subjects were close to acceptable. The age-related decrease in parenchymal CBF was augmented in arterial spin-labeling compared with phase-contrast MR imaging.


Assuntos
Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Espectroscopia de Ressonância de Spin Eletrônica , Marcadores de Spin , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
12.
Hum Reprod ; 30(7): 1704-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25994665

RESUMO

STUDY QUESTION: Is overweight associated with impaired sperm DNA integrity? SUMMARY ANSWER: High body mass index (BMI) is not associated with impaired sperm DNA integrity as assessed by the DNA Fragmentation Index (DFI). WHAT IS KNOWN ALREADY: Previous studies, based on fewer subjects and including mainly subfertile men, have shown conflicting results regarding the influence of overweight and obesity on sperm DNA integrity. STUDY DESIGN, SIZE, DURATION: This cross-sectional study was based on semen samples from 1503 men from the general population. PARTICIPANTS/MATERIALS, SETTING, METHODS: We included two cohorts (cohort A and B) of military recruits (n = 275, n = 304, respectively), one group (cohort C) of fertile men and men without known fertility problems (n = 724), and one group (cohort D) of men between 19 and 40 years without known fertility problems (n = 200). In all cohorts, data were available on BMI, DFI as measured by the sperm chromatin structure assay (SCSA), standard semen characteristics, and potential confounders (age, abstinence time, smoking habits). The subjects were categorized according to BMI into four groups: underweight (<18.5 kg/m(2)), normal weight (18.5-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)) and obese (≥30.0 kg/m(2)). Using a linear regression model, the inter-group differences in DFI were calculated. Furthermore with the normal-weight group as the reference, the odds ratios (ORs) for DFI > 20% and DFI > 30%, were calculated for the other groups. Calculations were made for the material as a whole and after exclusion of cohort C which included proven fertile men. MAIN RESULTS AND THE ROLE OF CHANCE: We found that normal-weight men had significantly higher DFI than overweight men, with a mean difference of 1.13% (95% CI: 1.05-1.22%); P = 0.001). Overweight men had a reduced risk of having DFI ≥ 20% and DFI ≥ 30%, compared with normal-weight men; adjusted odds ratio (OR) = 0.61 (95% CI: 0.42-0.88; P < 0.01) and adjusted OR = 0.48 (95% CI: 0.28-0.84; P < 0.01), respectively. When excluding cohort C, the statistical significance was lost. Regarding standard semen parameters, we found that obese men had a higher percentage of progressive motile spermatozoa than normal-weight men; mean difference 1.15% (95% CI: 1.02-1.30%, P < 0.05) but the significance was lost when excluding cohort C. All other standard semen parameters were unaffected by BMI. LIMITATIONS, REASONS FOR CAUTION: A main limitation might be the cross-sectional nature of the data. Furthermore our study included a significant proportion of men with proven fertility (75% of cohort C, n = 550), and could therefore be biased toward fertility. WIDER IMPLICATIONS OF THE FINDINGS: Our study indicates that overweight per se is not associated with a higher level of sperm DNA damage. STUDY FUNDING/COMPETING INTERESTS: This research has been given grants from the following: EU 5th and 7th framework program (Inuendo and Clear projects, [Contracts no. QLK4-CT-2001-00202 and FP7-ENV-2008-1-226217)]), the Swedish Research Council (Grants No. 2007-2590, 521-2004-6072 and 521-2002-3907); the Swedish Governmental Funding for Clinical Research, Skåne county council's research and development foundation, MAS Funds, University Hospital MAS Foundation in Malmö, Crafoordska Fund, Ove Tulefjords Fund, Foundation for Urological Research, Fundacion Federico SA, and Gunnar Nilssons Cancer Fund. The authors declare that there are no conflicts of interest.


Assuntos
Índice de Massa Corporal , Fragmentação do DNA , Sobrepeso , Sistema de Registros , Espermatozoides , Adolescente , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , União Europeia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Análise do Sêmen , Suécia/epidemiologia , Adulto Jovem
13.
Soft Matter ; 11(2): 414-21, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25408475

RESUMO

The peptide GSFSIQYTYHV derived from human semenogelin I forms a transparent hydrogel through spontaneous self-assembly in water at neutral pH. Linear rheology measurements demonstrate that the gel shows a dominating elastic response over a large frequency interval. CD, fluorescence and FTIR spectroscopy and cryo-TEM studies imply long fibrillar aggregates of extended ß-sheet. Dynamic light scattering data indicate that the fibril lengths are of the order of micrometers. Time-dependent thioflavin T fluorescence shows that fibril formation by GSFSIQYTYHV is a nucleated reaction. The peptide may serve as basis for development of smart biomaterials of low immunogenicity suitable for biomedical applications, including drug delivery and wound healing.


Assuntos
Hidrogel de Polietilenoglicol-Dimetacrilato/química , Peptídeos/química , Proteínas Secretadas pela Vesícula Seminal/química , Humanos , Concentração de Íons de Hidrogênio , Estrutura Secundária de Proteína , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Osteoporos Int ; 25(12): 2767-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25116384

RESUMO

UNLABELLED: This study of elderly Swedish women investigated the association between chronic vitamin D insufficiency and osteoporotic fractures occurring between ages 80-90. The incidence and risk of hip and major osteoporotic fractures was significantly higher in elderly women with low vitamin D levels maintained over 5 years. INTRODUCTION: Vitamin D insufficiency among the elderly is common; however, relatively little is known about the effects of long-term hypovitaminosis D on fracture. We investigated sequential assessment of serum 25(OH)D at age 75 and 80 to determine if continuously low 25(OH)D levels are associated with increased 10-year fracture incidence. METHODS: One thousand forty-four Swedish women from the population-based OPRA cohort, all 75 years old, attended at baseline (BL); 715 attended at 5 years. S-25(OH)D was available in 987 and 640, respectively and categorized as: <50 (Low), 50-75 (Intermediate), and >75 nmol/L (High). Incident fracture data was collected with maximum follow-up to 90 years of age. RESULTS: Hip fracture incidence between age 80-85 was higher in women who had low 25(OH)D at both baseline and 5 years (22.2 % (Low) vs. 6.6 % (High); p = 0.003). Between age 80-90, hip fracture incidence was more than double that of women in the high category (27.9 vs. 12.3 %; p = 0.006). Within 5-years, 50 % of women in the continuously low group compared to 34 % in the continuously high 25(OH)D group had an osteoporotic fracture (p = 0.004) while 10-year incidence was higher compared to the intermediate (p = 0.020) but not the high category (p = 0.053). The 10-year relative risk of hip fracture was almost three times higher and osteoporotic fracture risk almost doubled for women in the lowest 25(OH)D category compared to the high category (HR 2.7 and 1.7; p = 0.003 and 0.023, respectively). CONCLUSION: In these elderly women, 25(OH)D insufficiency over 5-years was associated with increased 10-year risk of hip and major osteoporotic fractures.


Assuntos
Fraturas por Osteoporose/etiologia , Deficiência de Vitamina D/complicações , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Estudos de Coortes , Feminino , Seguimentos , Fraturas do Quadril/sangue , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Humanos , Incidência , Fraturas por Osteoporose/sangue , Fraturas por Osteoporose/epidemiologia , Medição de Risco/métodos , Suécia/epidemiologia , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
15.
Int J Cancer ; 134(10): 2504-11, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24226765

RESUMO

There is growing evidence of the protective role of the Mediterranean diet (MD) on cancer. However, to date no epidemiological study has investigated the influence of the MD on bladder cancer. We evaluated the association between adherence to the MD and risk of urothelial cell bladder cancer (UCC), according to tumor aggressiveness, in the European Prospective Investigation into Cancer and Nutrition (EPIC). The analysis included 477,312 participants, recruited from ten European countries between 1991 and 2000. Information from validated dietary questionnaires was used to develop a relative Mediterranean diet score (rMED), including nine dietary components. Cox regression models were used to assess the effect of the rMED on UCC risk, while adjusting for dietary energy and tobacco smoking of any kind. Stratified analyses were performed by sex, BMI, smoking status, European region and age at diagnosis. During an average follow-up of 11 years, 1,425 participants (70.9% male) were diagnosed with a first primary UCC. There was a negative but non-significant association between a high versus low rMED score and risk of UCC overall (HR: 0.84 [95% CI 0.69, 1.03]) and risk of aggressive (HR: 0.88 [95% CI 0.61, 1.28]) and non-aggressive tumors (HR: 0.78 [95% CI 0.54, 1.14]). Although there was no effect modification in the stratified analyses, there was a significant 34% (p = 0.043) decreased risk of UCC in current smokers with a high rMED score. In EPIC, the MD was not significantly associated with risk of UCC, although we cannot exclude that a MD may reduce risk in current smokers.


Assuntos
Carcinoma de Células de Transição/epidemiologia , Dieta Mediterrânea , Neoplasias da Bexiga Urinária/epidemiologia , Idoso , Índice de Massa Corporal , Inquéritos sobre Dietas/métodos , Inquéritos sobre Dietas/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Preferências Alimentares , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Fumar , Inquéritos e Questionários , Fatores de Tempo
16.
AJNR Am J Neuroradiol ; 34(9): 1740-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23493888

RESUMO

BACKGROUND AND PURPOSE: 4D PCMRI can be used to quantify pulsatile hemodynamics in multiple cerebral arteries. The aim of this study was to compare 4D PCMRI and 2D PCMRI for assessments of pulsatile hemodynamics in major cerebral arteries. MATERIALS AND METHODS: We scanned the internal carotid artery, the anterior cerebral artery, the basilar artery, and the middle cerebral artery in 10 subjects with a single 4D and multiple 2D PCMRI acquisitions by use of a 3T system and a 32-channel head coil. We assessed the agreement regarding net flow and the volume of arterial pulsatility (ΔV) for all vessels. RESULTS: 2D and 4D PCMRI produced highly correlated results, with r = 0.86 and r = 0.95 for ΔV and net flow, respectively (n = 69 vessels). These values increased to r = 0.93 and r = 0.97, respectively, during investigation of a subset of measurements with <5% variation in heart rate between the 4D and 2D acquisition (n = 31 vessels). Significant differences were found for ICA and MCA net flow (P = .004 and P < .001, respectively) and MCA ΔV (P = .006). However, these differences were attenuated and no longer significant when the subset with stable heart rate (n = 31 vessels) was analyzed. CONCLUSIONS: 4D PCMRI provides a powerful methodology to measure pulsatility of the larger cerebral arteries from a single acquisition. A large part of differences between measurements was attributed to physiologic variations. The results were consistent with 2D PCMRI.


Assuntos
Volume Sanguíneo/fisiologia , Encéfalo/fisiopatologia , Artérias Cerebrais/fisiologia , Circulação Cerebrovascular/fisiologia , Angiografia por Ressonância Magnética/métodos , Fluxo Pulsátil/fisiologia , Adolescente , Adulto , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/patologia , Técnicas de Imagem de Sincronização Cardíaca/métodos , Criança , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Neurônios , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
17.
Lab Chip ; 13(9): 1790-6, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23515524

RESUMO

On-chip detection of low abundant protein biomarkers is of interest to enable point-of-care diagnostics. Using a simple form of integration, we have realized an integrated microfluidic platform for the detection of prostate specific antigen (PSA), directly in anti-coagulated whole blood. We combine acoustophoresis-based separation of plasma from undiluted whole blood with a miniaturized immunoassay system in a polymer manifold, demonstrating improved assay speed on our Integrated Acoustic Immunoaffinity-capture (IAI) platform. The IAI platform separates plasma from undiluted whole blood by means of acoustophoresis and provides cell free plasma of clinical quality at a rate of 10 uL/min for an online immunoaffinity-capture of PSA on a porous silicon antibody microarray. The whole blood input (hematocrit 38-40%) rate was 50 µl min(-1) giving a plasma volume fraction yield of ≈33%. PSA was immunoaffinity-captured directly from spiked female whole blood samples at clinically significant levels of 1.7-100 ng ml(-1) within 15 min and was subsequently detected via fluorescence readout, showing a linear response over the entire range with a coefficient of variation of 13%.


Assuntos
Técnicas Analíticas Microfluídicas , Antígeno Prostático Específico/sangue , Acústica , Adulto , Biomarcadores/sangue , Feminino , Humanos , Técnicas de Imunoadsorção/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
18.
Acta Neurol Scand ; 128(1): 17-23, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23278837

RESUMO

INTRODUCTION: Infusion tests are used to diagnose and select patients with idiopathic normal pressure hydrocephalus (INPH) for shunt surgery. The test characterizes cerebrospinal fluid dynamics and estimates parameters of the cerebrospinal fluid system, the pressure-volume index (PVI) and the outflow conductance (Cout). The Oscillating Pressure Infusion (OPI) method was developed to improve the test and reduce the investigation time. The aim of this study was to evaluate the new OPI method by comparing it with an established reference method. METHODS: Forty-seven patients (age 71.2 ± 8.9 years) with communicating hydrocephalus underwent a preoperative lumbar infusion investigation with two consecutive infusion protocols, reference (42 min) and new (20 min), that is, 94 infusion tests in total. The OPI method estimated Cout and PVI simultaneously. A real-time analysis of reliability was applied to investigate the possibility of infusion time reduction. RESULTS: The difference in Cout between the methods was 1.2 ± 1.8 µl/s/kPa (ΔRout = -0.8 ± 3.5 mmHg/ml/min), P < 0.05, n = 47. With the reliability analysis, the preset 20 min of active infusion could have been even further reduced for 19 patients to between 10 and 19 min. PVI was estimated to 16.1 ± 6.9 ml, n = 47. CONCLUSIONS: The novel Oscillating Pressure Infusion method produced real-time estimates of Cout including estimates of reliability that was in good agreement with the reference method and allows for a reduced and individualized investigation time.


Assuntos
Pressão do Líquido Cefalorraquidiano/fisiologia , Derivações do Líquido Cefalorraquidiano , Técnicas de Diagnóstico Neurológico , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/fisiopatologia , Infusão Espinal , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hidrocefalia de Pressão Normal/terapia , Masculino , Reprodutibilidade dos Testes , Reologia , Fatores de Tempo
19.
Acta Neurol Scand ; 127(4): 233-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22784234

RESUMO

OBJECTIVE: The aim of this study was to investigate whether pulsations measured in the brain correspond to those measured in lumbar space, and subsequently whether lumbar punctures could replace invasive recordings. METHODS: In ten patients with normal pressure hydrocephalus, simultaneous recordings of the intracranial pressure (ICP; intraparenchymal) and lumbar pressure (LP; cerebrospinal fluid pressure) were performed. During registration, pressure was altered between resting pressure and 45 mmHg using an infusion test. Data were analyzed regarding pulsations (i.e., amplitudes). Also, the pressure sensors were compared in a bench test. RESULTS: The correlation between intracranial and lumbar amplitudes was 0.98. At resting pressure, and moderately elevated ICP, intracranial pulse amplitudes exceeded that of lumbar space with about 0.9 mmHg. At the highest ICP, the difference changed to -0.2 mmHg. The bench test showed that the agreement of sensor readings was good at resting pressure, but reduced at higher amplitudes. CONCLUSIONS: Compared to intracranial registrations, amplitudes measured through lumbar puncture were slightly attenuated. The bench test showed that differences were not attributable to dissimilarities of the sensor systems. A lumbar pressure amplitude measurement is an alternative to ICP recording, but the thresholds for what should be interpreted as elevated amplitudes need to be adjusted.


Assuntos
Pressão do Líquido Cefalorraquidiano/fisiologia , Hidrocefalia de Pressão Normal/fisiopatologia , Pressão Intracraniana/fisiologia , Punção Espinal , Idoso , Feminino , Seguimentos , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino
20.
AJNR Am J Neuroradiol ; 33(10): 1951-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22555574

RESUMO

BACKGROUND AND PURPOSE: Brain size is commonly described in relation to ICV, whereby accurate assessment of this quantity is fundamental. Recently, an optimized MR sequence (QRAPMASTER) was developed for simultaneous quantification of T1, T2, and proton density. ICV can be measured automatically within minutes from QRAPMASTER outputs and a dedicated software, SyMRI. Automatic estimations of ICV were evaluated against the manual segmentation. MATERIALS AND METHODS: In 19 healthy subjects, manual segmentation of ICV was performed by 2 neuroradiologists (Obs1, Obs2) by using QBrain software and conventional T2-weighted images. The automatic segmentation from the QRAPMASTER output was performed by using SyMRI. Manual corrections of the automatic segmentation were performed (corrected-automatic) by Obs1 and Obs2, who were blinded from each other. Finally, the repeatability of the automatic method was evaluated in 6 additional healthy subjects, each having 6 repeated QRAPMASTER scans. The time required to measure ICV was recorded. RESULTS: No significant difference was found between reference and automatic (and corrected-automatic) ICV (P > .25). The mean difference between the reference and automatic measurement was -4.84 ± 19.57 mL (or 0.31 ± 1.35%). Mean differences between the reference and the corrected-automatic measurements were -0.47 ± 17.95 mL (-0.01 ± 1.24%) and -1.26 ± 17.68 mL (-0.06 ± 1.22%) for Obs1 and Obs2, respectively. The repeatability errors of the automatic and the corrected-automatic method were <1%. The automatic method required 1 minute 11 seconds (SD = 12 seconds) of processing. Adding manual corrections required another 1 minute 32 seconds (SD = 38 seconds). CONCLUSIONS: Automatic and corrected-automatic quantification of ICV showed good agreement with the reference method. SyMRI software provided a fast and reproducible measure of ICV.


Assuntos
Algoritmos , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Adulto , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Tamanho do Órgão/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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