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1.
BMC Nephrol ; 24(1): 168, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308813

RESUMO

BACKGROUND: A vegetarian diet is a popular alternative to the casual diet - it is considered healthy, and was proven to positively affect cardiovascular health. The Chronic Kidney Disease (CKD) progression is a major issue in the healthcare system, and constitutes a leading cause of death for 1.5% of the global population. The objective of this systematic review was to investigate the potential impact of a vegetarian diet on kidney function in CKD patients. METHOD: Our systematic review focused on randomized controlled trials (RCTs) which compared the effects of a vegetarian diet (experimental) and a standard omnivore diet (comparator) in terms of the estimated glomerular filtration rate (eGFR) in CKD patients. Inclusion criteria were based on PICO elements, with two researchers involved in browsing the Cochrane and Pubmed search engines. The investigation was performed using the PRISMA 2020 Checklist and PRISMA 2020 flow diagram. The search terms included: 'vegetarian diet' AND 'nephropathy', 'eGFR', 'albuminuria', 'chronic kidney disease'. Bias assessment was performed using RoB 2 tool to determine the validity of the data collected from studies. RESULTS: Four RCTs with a total of 346 participants were included in the presented systematic review. Two largest RCTs reported an increase in eGFR following a change to a vegetarian diet (p = 0.01 and p = 0.001). Another two found no significant differences between the experimental and control groups, also these trials were associated with a high risk of bias in terms of missing data outcome and the randomization process. CONCLUSIONS: The findings collected in this systematic review suggest that a vegetarian diet improves renal filtration function in CKD patients. Therefore, it seems essential to conduct further research involving the impact of the diet on the progression of CKD.


Assuntos
Dieta Vegetariana , Insuficiência Renal Crônica , Humanos , Albuminúria , Lista de Checagem , Vegetarianos
2.
J Chem Phys ; 146(2): 024109, 2017 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-28088153

RESUMO

We investigate how correlated fluctuations affect oscillatory features in rephasing and non-rephasing two-dimensional (2D) electronic spectra of a model dimer system. Based on a beating map analysis, we show that non-secular environmental couplings induced by uncorrelated fluctuations lead to oscillations centered at both cross- and diagonal-peaks in rephasing spectra as well as in non-rephasing spectra. Using an analytical approach, we provide a quantitative description of the non-secular effects in terms of the Feynman diagrams and show that the environment-induced mixing of different inter-excitonic coherences leads to oscillations in the rephasing diagonal-peaks and non-rephasing cross-peaks. We demonstrate that as correlations in the noise increase, the lifetime of oscillatory 2D signals is enhanced at rephasing cross-peaks and non-rephasing diagonal-peaks, while the other non-secular oscillatory signals are suppressed. We discuss that the asymmetry of 2D lineshapes in the beating map provides information on the degree of correlations in environmental fluctuations. Finally we investigate how the oscillatory features in 2D spectra are affected by inhomogeneous broadening.

3.
J Chem Phys ; 142(6): 064104, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25681884

RESUMO

We challenge the misconception that Bloch-Redfield equations are a less powerful tool than phenomenological Lindblad equations for modeling exciton transport in photosynthetic complexes. This view predominantly originates from an indiscriminate use of the secular approximation. We provide a detailed description of how to model both coherent oscillations and several types of noise, giving explicit examples. All issues with non-positivity are overcome by a consistent straightforward physical noise model. Herein also lies the strength of the Bloch-Redfield approach because it facilitates the analysis of noise-effects by linking them back to physical parameters of the noise environment. This includes temporal and spatial correlations and the strength and type of interaction between the noise and the system of interest. Finally, we analyze a prototypical dimer system as well as a 7-site Fenna-Matthews-Olson complex in regards to spatial correlation length of the noise, noise strength, temperature, and their connection to the transfer time and transfer probability.

4.
Epigenomics ; 16(7): 473-491, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38511224

RESUMO

Neurological diseases are multifactorial, genetic and environmental. Environmental factors such as diet, physical activity and emotional state are epigenetic factors. Environmental markers are responsible for epigenetic modifications. The effect of epigenetic changes is increased inflammation of the nervous system and neuronal damage. In recent years, it has been shown that epigenetic changes may cause an increased risk of neurological disorders but, currently, the relationship between epigenetic modifications and neurodegeneration remains unclear. This review summarizes current knowledge about neurological disorders caused by epigenetic changes in diseases such as Alzheimer's disease, Parkinson's disease, stroke and epilepsy. Advances in epigenetic techniques may be key to understanding the epigenetics of central changes in neurological diseases.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doenças Neurodegenerativas/genética , Epigênese Genética , Doença de Alzheimer/genética , Doença de Parkinson/genética , Dieta , Metilação de DNA
5.
Sci Adv ; 10(39): eadj3933, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331705

RESUMO

Diamond is a potential host material for laser applications due to its exceptional thermal properties, ultrawide bandgap, and color centers, which promise gain across the visible spectrum. More recently, coherent laser methods offer improved sensitivity for magnetometry. However, diamond fabrication is difficult in comparison to other crystalline matrices, and many optical loss channels are not yet understood. Here, we demonstrate a continuous-wave laser threshold as a function of the pump intensity on nitrogen-vacancy (NV) color centers. To achieve this, we constructed a laser cavity with both an NV diamond medium and an intracavity antireflection-coated diode laser. This dual-medium approach compensates intrinsic losses of the cavity by providing a fixed additional gain below threshold of the diode laser. We observe a continuous-wave laser threshold of the laser system and linewidth narrowing with increasing green pump power on the NV centers. Our results are a major development toward coherent approaches to magnetometry.

6.
Radiographics ; 33(6): 1589-612, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24108553

RESUMO

Identifying the presence of axillary node and internal mammary node metastases in patients with invasive breast cancer is critical for determining prognosis and for deciding on appropriate treatment. Sentinel lymph node biopsy (SLNB) is the definitive method to exclude axillary metastases. Patients with positive SLNB results generally undergo axillary lymph node dissection (ALND). The benefit of preoperative identification of axillary metastases is that it allows the surgeon to proceed directly to ALND and to avoid an unnecessary SLNB and the need for a second surgical procedure involving the axillary nodes. Knowledge of the important anatomic landmarks of the axilla is important in finding and accurately reporting suspicious lymph nodes. The pathologic features of nodal metastases illuminate the imaging appearances of these nodes, as depicted with all modalities. Ultrasonography (US) is the primary imaging modality for evaluating axillary nodes. Morphologic criteria, such as cortical thickening, hilar effacement, and nonhilar cortical blood flow, are more important than size criteria in the identification of metastases. US-guided lymph node sampling, especially with core biopsy, is invaluable in confirming the presence of a metastasis in a suspicious node. Core biopsy has been shown to be equal in safety to fine needle aspiration and has a significantly lower false-negative rate. Magnetic resonance imaging is also useful, with the added benefit of providing a global view of both axillae. Computed tomography and radionuclide imaging play a lesser role in imaging the axilla. Preoperative image-based identification and sampling of abnormal lymph nodes that have a high positive predictive value for metastases is an extremely important component in the management of patients with invasive breast cancer.


Assuntos
Axila/patologia , Neoplasias da Mama/patologia , Diagnóstico por Imagem , Metástase Linfática/patologia , Algoritmos , Biópsia por Agulha Fina , Feminino , Humanos , Excisão de Linfonodo , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias
7.
Bioengineering (Basel) ; 9(4)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35447706

RESUMO

Linking community composition and ecosystem function via the cultivation-independent analysis of marker genes, e.g., the 16S rRNA gene, is a staple of microbial ecology and dependent disciplines. The certainty of results, independent of the bioinformatic handling, is imperative for any advances made within the field. In this work, thermophilic anaerobic co-digestion experimental data, together with primary and waste-activated sludge prokaryotic community data, were analyzed with two pipelines that apply different principles when dealing with technical, sequencing, and PCR biases. One pipeline (VSEARCH) employs clustering methods, generating individual operational taxonomic units (OTUs), while the other (DADA2) is based on sequencing error correction algorithms and generates exact amplicon sequence variants (ASVs). The outcomes of both pipelines were compared within the framework of ecological-driven data analysis. Both pipelines provided comparable results that would generally allow for the same interpretations. Yet, the two approaches also delivered community compositions that differed between 6.75% and 10.81% between pipelines. Inconsistencies were also observed linked to biologically driven variability in the samples, which affected the two pipelines differently. These pipeline-dependent differences in taxonomic assignment could lead to different conclusions and interfere with any downstream analysis made for such mis- or not-identified species, e.g., network analysis or predictions of their respective ecosystem service.

8.
Sci Adv ; 8(22): eabn7192, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658038

RESUMO

Negatively charged nitrogen-vacancy (NV) centers in diamond are promising magnetic field quantum sensors. Laser threshold magnetometry theory predicts improved NV center ensemble sensitivity via increased signal strength and magnetic field contrast. Here, we experimentally demonstrate laser threshold magnetometry. We use a macroscopic high-finesse laser cavity containing a highly NV-doped and low absorbing diamond gain medium that is pumped at 532 nm and resonantly seeded at 710 nm. This enables a 64% signal power amplification by stimulated emission. We test the magnetic field dependency of the amplification and thus demonstrate magnetic field-dependent stimulated emission from an NV center ensemble. This emission shows an ultrahigh contrast of 33% and a maximum output power in the milliwatt regime. The coherent readout of NV centers pave the way for novel cavity and laser applications of quantum defects and diamond NV magnetic field sensors with substantially improved sensitivity for the health, research, and mining sectors.

9.
Bioengineering (Basel) ; 8(12)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34940350

RESUMO

Anaerobic co-digestion (Co-AD) is used to increase the effectiveness of anaerobic digestion (AD) using local "wastes", adding economic and environmental benefits. Since system stability is of existential importance for the operation of wastewater treatment plants, thorough testing of potential co-substrates and their effects on the respective community and system performance is crucial for understanding and utilizing Co-AD to its best capacity. Food waste (FW) and canola lecithin (CL) were tested in mesophilic, lab-scale, semi-continuous reactors over a duration of 120 days with stepwise increased substrate addition. Key performance indicators (biogas, total/volatile solids, fatty acids) were monitored and combined with 16S-rRNA amplicon sequencing to assess the impact of co-substrate addition on reactor performance and microbial community composition (MCC). Additionally, the latter was then compared with natural shifts occurring in the wastewater treatment plant (WWTP, source) at the same time. An almost linear increase in biogas production with both co-substrates at an approximate 1:1 ratio with the organic loading rate (OLR) was observed. The MCCs in both experiments were mostly stable, but also prone to drift over time. The FW experiment MCC more closely resembled the original WWTP community and the observed shifts indicated high levels of functional redundancy. Exclusive to the CL co-substrate, a clear selection for a few operational taxonomic units (OTUs) was observed. There was little evidence for a persistent invasion and establishment of microorganisms from typical primary substrates into the stable resident community of the reactors, which is in line with earlier findings that suggested that the inoculum and history mostly define the MCC. However, external factors may still tip the scales in favor of a few r-strategists (e.g., Prolixibacter) in an environment that otherwise favors K-strategists, which may in fact also be recruited from the primary substrate (Trichococcus). In our study, specialization and diversity loss were also observed in response to the addition of the highly specialized CL, which in turn, may have adverse effects on the system's stability and reduced resilience and recovery.

10.
Sci Rep ; 8(1): 1268, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29352215

RESUMO

Traditional optical fibers are insensitive to magnetic fields, however many applications would benefit from fiber-based magnetometry devices. In this work, we demonstrate a magnetically sensitive optical fiber by doping nanodiamonds containing nitrogen vacancy centers into tellurite glass fibers. The fabrication process provides a robust and isolated sensing platform as the magnetic sensors are fixed in the tellurite glass matrix. Using optically detected magnetic resonance from the doped nanodiamonds, we demonstrate detection of local magnetic fields via side excitation and longitudinal collection. This is a first step towards intrinsically magneto-sensitive fiber devices with future applications in medical magneto-endoscopy and remote mineral exploration sensing.

11.
Sci Rep ; 7: 41472, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134271

RESUMO

Magnonics is an emerging field with potential applications in classical and quantum information processing. Freely propagating magnons in two-dimensional media are subject to dispersion, which limits their effective range and utility as information carriers. We show the design of a confining magnonic waveguide created by two surface current carrying wires placed above a spin-sheet, which can be used as a primitive for reconfigurable magnonic circuitry. We theoretically demonstrate the ability of such guides to counter the transverse dispersion of the magnon in a spin-sheet, thus extending the range of the magnon. A design of a magnonic directional coupler and controllable Michelson interferometer is shown, demonstrating its utility for information processing tasks.

12.
Nat Commun ; 8: 14000, 2017 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-28128228

RESUMO

Stimulated emission is the process fundamental to laser operation, thereby producing coherent photon output. Despite negatively charged nitrogen-vacancy (NV-) centres being discussed as a potential laser medium since the 1980s, there have been no definitive observations of stimulated emission from ensembles of NV- to date. Here we show both theoretical and experimental evidence for stimulated emission from NV- using light in the phonon sidebands around 700 nm. Furthermore, we show the transition from stimulated emission to photoionization as the stimulating laser wavelength is reduced from 700 to 620 nm. While lasing at the zero-phonon line is suppressed by ionization, our results open the possibility of diamond lasers based on NV- centres, tuneable over the phonon sideband. This broadens the applications of NV- magnetometers from single centre nanoscale sensors to a new generation of ultra-precise ensemble laser sensors, which exploit the contrast and signal amplification of a lasing system.

13.
Arch Surg ; 138(6): 619-22; discussion 622-3, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12799332

RESUMO

BACKGROUND: Nonpalpable mammographic abnormalities are frequently evaluated by means of a stereotactic core needle biopsy. This technique is a very sensitive indicator of invasive cancer, but is less reliable to discriminate between ductal carcinoma in situ and atypical ductal hyperplasia (ADH). The objective of this study was to determine the correlation of the 11-gauge vacuum-assisted core needle biopsy to open biopsy when a diagnosis of ADH is obtained. HYPOTHESIS: The use of 11-gauge vacuum-assisted stereotactic core needle biopsy does not conclusively diagnose ADH. DESIGN: Retrospective analysis. SETTING: University-affiliated teaching hospital. PATIENTS: Mammographic findings were evaluated with an 11-gauge vacuum-assisted stereotactic core biopsy in 1750 patients. Seventy-seven patients were diagnosed as having ADH; of these, 65 underwent excisional biopsy. MAIN OUTCOME MEASURES: Pathological upstaging rate. RESULTS: Of the 65 patients who underwent excisional breast biopsy, 11 (17%) had their condition upstaged to a breast cancer diagnosis. These patients had presented at a later age than those who retained a benign diagnosis after excisional biopsy. The number of cores taken did not correlate with diagnostic accuracy. CONCLUSIONS: Of the 65 patients who underwent open biopsy for ADH in this series, only 83% had an accurate diagnosis. A diagnosis of ADH by stereotactic core needle biopsy should be followed by an open excisional biopsy.


Assuntos
Biópsia por Agulha/métodos , Neoplasias da Mama/patologia , Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Lesões Pré-Cancerosas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Mama/cirurgia , Feminino , Humanos , Hiperplasia , Mamografia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos
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