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1.
Food Chem ; 462: 140925, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39190981

ABSTRACT

Grape pomace (GP) and pecan shell (PS) are two by-products rich in phenolic compounds (PC), and dietary fiber (DF) that may be considered for the development of functional baked foods. In this study, four formulations with different GP:PS ratios (F1(8%:5%), F2(5%:5%), F3(5%:2%), F4(0%:5%), and control bread (CB)) were elaborated and characterized (physiochemical and phytochemical content). Also, their inner structure (SEM), changes in their FTIR functional group's vibrations, and the bioaccessibility of PC and sugars, including an in vitro glycemic index, were analyzed. Results showed that all GP:PS formulations had higher mineral, protein, DF (total, soluble, and insoluble), and PC content than CB. Additionally, PC and non-starch polysaccharides affected gluten and starch absorbance and pores distribution. In vitro digestion model showed a reduction in the glycemic index for all formulations, compared to CB. These findings highlight the possible health benefits of by-products and their interactions in baked goods.


Subject(s)
Bread , Dietary Fiber , Glycemic Index , Phenols , Vitis , Dietary Fiber/analysis , Dietary Fiber/metabolism , Bread/analysis , Vitis/chemistry , Phenols/chemistry , Phenols/metabolism , Humans , Digestion , Food, Fortified/analysis , Waste Products/analysis
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124962, 2025 Jan 05.
Article in English | MEDLINE | ID: mdl-39146628

ABSTRACT

Two isostructural, three-dimensional, interpenetrated amino-functionalized Metal-Organic Frameworks (Co-2AIN-MOF and Cd-2AIN-MOF) based on 2-aminoisonicotinic acid (2AIN) were synthesized, structurally characterized and determined. Based on the PXRD analysis, the solvent exchange hardly changed their framework structure, and the samples fully activated by methanol can be achieved and examined by infrared spectroscopy. Due to the presence of the carbonyl group and free amino groups in the pore of the framework, the NH3 uptakes of Co-2AIN-MOF and Cd-2AIN-MOF are 11.70 and 13.81 mmol/g and at 1 bar, respectively. In-situ Infrared spectroscopy and DFT calculations revealed the different adsorption sites and processes between Co-2AIN-MOF and Cd-2AIN-MOF.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125000, 2025 Jan 05.
Article in English | MEDLINE | ID: mdl-39180968

ABSTRACT

Fourier transform infrared spectroscopy (FTIRS) can provide rich information on the composition and content of samples, enabling the detection of subtle changes in tissue composition and structure. This study represents the first application of FTIRS to investigate cartilage under microgravity. Simulated microgravity cartilage model was firstly established by tail-suspension (TS) for 7, 14 and 21 days, which would be compared to control samples. A self-developed hollow optical fiber attenuated total reflection (HOF-ATR) probe coupled with a FTIR spectrometer was used for the spectral acquisition of cartilage samples in situ, and one-way analysis of variance (ANOVA) was employed to analyze the changes in the contents of cartilage matrix at different stages. The results indicate that cartilage degenerates in microgravity, the collagen content gradually decreases with the TS time, and the structure of collagen fibers changes. The trends of proteoglycan content and collagen integrity show an initial decrease followed by an increase, ultimately significantly decreasing. The findings provide the basis for the cartilage degeneration in microgravity with TS time, which must be of real significance for space science and health detection.


Subject(s)
Cartilage, Articular , Collagen , Weightlessness Simulation , Spectroscopy, Fourier Transform Infrared/methods , Cartilage, Articular/pathology , Cartilage, Articular/chemistry , Cartilage, Articular/metabolism , Collagen/analysis , Collagen/metabolism , Collagen/chemistry , Animals , Proteoglycans/analysis , Male
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125029, 2025 Jan 05.
Article in English | MEDLINE | ID: mdl-39213833

ABSTRACT

The near-infrared spectral data is highly high dimensional and contains redundant information, it is necessary to identify the most representative characteristic wavelengths before modeling to improve model accuracy and reliability. At present, there are many methods for selecting the characteristic wavelengths of NIR spectroscopy, but the collinearity among wavelengths is still a main issue that leads to poor model effects. Therefore, this study proposes a three-stage wavelength selection algorithm (Stage III) to reduce redundancy in NIR spectral data and collinearity between wavelength variables, resulting in a simpler and more accurate predictive model. The research uses a public NIR data set of corn samples as its subject. Initially, the wavelengths with the higher correlation coefficients are chosen after calculating the relationship coefficients between every wavelength vector and the concentration vector. On this basis, the correlation coefficients between the vectors of each wavelength point are calculated, and those wavelength points with smaller correlation coefficients with other wavelength points are selected. Ultimately, the stepwise regression analysis selects the wavelengths that provide substantial value to the model as the variables for modeling, leading to the development of a multiple linear regression model. The results show that the model using the three-stage wavelength selection algorithm outperforms those using the full spectrum, Stages I and Stage II, and the coefficient of determination of the test set of the Stage III-MLR model achieved an accuracy of 0.9360. Instead of the successive projections algorithm (SPA), uninformative variable elimination (UVE), and competitive adaptive reweighted sampling (CARS), Stage III is better in the model prediction accuracy. Therefore, the three-stage wavelength selection algorithm is an effective wavelength selection algorithm that can effectively model NIR spectroscopy, reduce the collinearity between the wavelength variables, simplify the complexity of the model, and improve the prediction precision of the model.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124992, 2025 Jan 05.
Article in English | MEDLINE | ID: mdl-39163771

ABSTRACT

Curcumae Radix (CR) is a widely used traditional Chinese medicine with significant pharmaceutical importance, including enhancing blood circulation and addressing blood stasis. This study aims to establish an integrated and rapid quality assessment method for CR from various botanical origins, based on chemical components, antiplatelet aggregation effects, and Fourier transform near-infrared (FT-NIR) spectroscopy combined with multivariate algorithms. Firstly, ultra-performance liquid chromatography-photodiode array (UPLC-PDA) combined with chemometric analyses was used to examine variations in the chemical profiles of CR. Secondly, the activation effect on blood circulation of CR was assessed using an in vitro antiplatelet aggregation assay. The studies revealed significant variations in chemical profiles and antiplatelet aggregation effects among CR samples from different botanical origins, with constituents such as germacrone, ß-elemene, bisdemethoxycurcumin, demethoxycurcumin, and curcumin showing a positive correlation with antiplatelet aggregation biopotency. Thirdly, FT-NIR spectroscopy was integrated with various machine learning algorithms, including Artificial Neural Network (ANN), K-Nearest Neighbors (KNN), Logistic Regression (LR), Support Vector Machine (SVM), and Subspace K-Nearest Neighbors (Subspace KNN), to classify CR samples from four distinct sources. The result showed that FT-NIR combined with KNN and SVM classification algorithms after SNV and MSC preprocessing successfully distinguished CR samples from four plant sources with an accuracy of 100%. Finally, Quantitative models for active constituents and antiplatelet aggregation bioactivity were developed by optimizing the partial least squares (PLS) model with interval combination optimization (ICO) and competitive adaptive reweighted sampling (CARS) techniques. The CARS-PLS model achieved the best predictive performance across all five components. The coefficient of determination (R2p) and root mean square error (RMSEP) in the independent test sets were 0.9708 and 0.2098, 0.8744 and 0.2065, 0.9511 and 0.0034, 0.9803 and 0.0066, 0.9567 and 0.0172 for germacrone, ß-elemene, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively. The ICO-PLS model demonstrated superior predictive capabilities for antiplatelet aggregation biotency, achieving an R2p of 0.9010, and an RMSEP of 0.5370. This study provides a valuable reference for the quality evaluation of CR in a more rapid and comprehensive manner.


Subject(s)
Curcuma , Platelet Aggregation Inhibitors , Platelet Aggregation , Spectroscopy, Near-Infrared , Curcuma/chemistry , Spectroscopy, Near-Infrared/methods , Platelet Aggregation/drug effects , Spectroscopy, Fourier Transform Infrared/methods , Platelet Aggregation Inhibitors/analysis , Platelet Aggregation Inhibitors/chemistry , Animals , Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/analysis , Algorithms , Plant Extracts/chemistry
6.
Food Chem ; 462: 141033, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39217750

ABSTRACT

A rapid method was developed for determining the total flavonoid and protein content in Tartary buckwheat by employing near-infrared spectroscopy (NIRS) and various machine learning algorithms, including partial least squares regression (PLSR), support vector regression (SVR), and backpropagation neural network (BPNN). The RAW-SPA-CV-SVR model exhibited superior predictive accuracy for both Tartary and common buckwheat, with a high coefficient of determination (R2p = 0.9811) and a root mean squared error of prediction (RMSEP = 0.1071) for flavonoids, outperforming both PLSR and BPNN models. Additionally, the MMN-SPA-PSO-SVR model demonstrated exceptional performance in predicting protein content (R2p = 0.9247, RMSEP = 0.3906), enhancing the effectiveness of the MMN preprocessing technique for preserving the original data distribution. These findings indicate that the proposed methodology could efficiently assess buckwheat adulteration analysis. It can also provide new insights for the development of a promising method for quantifying food adulteration and controlling food quality.


Subject(s)
Fagopyrum , Flavonoids , Plant Proteins , Spectroscopy, Near-Infrared , Fagopyrum/chemistry , Spectroscopy, Near-Infrared/methods , Flavonoids/analysis , Flavonoids/chemistry , Plant Proteins/analysis , Plant Proteins/chemistry , Chemometrics/methods , Least-Squares Analysis , Neural Networks, Computer
7.
Eur J Pediatr ; 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39387903

ABSTRACT

Cyclic phototherapy (cPT) can achieve a reduction in total serum bilirubin comparable to that achieved with standard continuous PT in preterm infants. Our aim was to assess the effect of cPT on splanchnic (rSO2S) and cerebral (rSO2C) oxygenation measured by near-infrared spectroscopy (NIRS). We prospectively studied 16 infants with a gestational age of 25-34 weeks with hyperbilirubinemia requiring PT. Splanchnic regional oxygenation (rSO2S), oxygen extraction fraction (FOES), and cerebro-splanchnic oxygenation ratio (CSOR) were recorded before, during, and after cPT discontinuation. We found that rSO2S, FOES, and CSOR did not change during the study period. The overall duration of single or multiple courses of PT was 6.5 (6.0-13.5) h, but by cycling PT, the actual exposure was 3.0 (1.5-4.9) h. Twelve patients (75%) required 15 min/h cPT, and four (25%) required prolonging cPT to 30 min/h. None of the patients developed enteral feeding intolerance. Conclusions: cPT treatment of hyperbilirubinemia in preterm infants does not affect splanchnic oxygenation or intestinal oxygen blood extraction, likely due to the short exposure to PT light, and it could contribute to decreasing the risk of feeding intolerance.

8.
Talanta ; 282: 126930, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39357406

ABSTRACT

Diabetic nephropathy (DN) is a major cause of global kidney failure. While histological kidney biopsy is the gold standard for diagnosis, it primarily reveals tissue morphology. In contrast, near-infrared (NIR) microscopy offers a label-free method for detailed molecular characterization of kidney tissue. Hematoxylin and eosin-stained kidney tissue samples from 17 ob/ob mice with DN and 14 healthy mice were examined using Fourier transform-NIR microscopy. Four different spectra were obtained from both the mesangium and tubulus. NIR spectral analysis unveiled distinct differences in wavenumbers between DN-affected and healthy kidneys, notably in the carbohydrate and protein-associated region (5500-4200 cm-1). In the mesangium, DN tissue samples exhibited higher median values at 4235 cm-1, 4659 cm-1, 4844 cm-1, 4906 cm-1, and 5222 cm-1 compared to controls (P < 0.05, P < 0.01, P < 0.05, P < 0.05 and P < 0.001, respectively). In tubular spectra, higher median values were found at 4258 cm-1, 4659 cm-1, 5222 cm-1, and 5346 cm-1 in the DN group (P < 0.01, P < 0.05, P < 0.05 and P < 0.01, respectively). These spectral differences strongly correlated with metabolic, histologic, and urinary parameters, providing valuable DN progression insights. The classification model achieved a visible clustering between the control and DN group for both the mesangial and tubular measurements. NIR microscopy demonstrated significant spectral differences between DN and healthy kidney tissues in mice, hinting at its potential for providing chemical insights, aiding in more accurate diagnoses, and offering a foundation for further clinical exploration and potential therapeutic advancements in DN.

9.
Chemphyschem ; : e202400632, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39365614

ABSTRACT

Hydro-chloro-fluoro-carbons (HCFCs) are potent greenhouse gases which strongly absorb the infrared (IR) radiation within the 8 - 12 µm atmospheric windows. Despite international policies schedule their phasing out by 2020 for developed countries and 2030 globally, HCFC-132b (CH2ClCClF2) has been recently detected with significant atmospheric concentration. In this scenario, detailed climate metrics are of paramount importance for understanding the capacity of anthropogenic pollutants to contribute to global warming. In this work, the radiative efficiency (RE) of HCFC-132b is experimentally measured for the first time and used to determine its global warming potential (GWP) over 20-, 100- and 500-year time horizon. Vibrational- and rotational-spectroscopic properties of this molecule are first characterized by exploiting a synergism between Fourier-transform IR (FTIR) spectroscopy experiments and quantum chemical calculations. Equilibrium geometry, rotational parameters and vibrational properties predicted theoretically beyond the double-harmonic approximation, are employed to assist the vibrational assignment  of the experimental trace. Finally, FTIR spectra measured over a range of pressures are used to determine HCFC-132b absorption cross section spectrum from 150 to 3000 cm-1, from which istantaneous and effective REs are derived and, in turn, used for GWP evaluation.

10.
Brain Topogr ; 38(1): 4, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39367153

ABSTRACT

Tactile and motor imagery are crucial components of sensorimotor functioning and cognitive neuroscience research, yet the neural mechanisms of tactile imagery remain underexplored compared to motor imagery. This study employs multichannel functional near-infrared spectroscopy (fNIRS) combined with image reconstruction techniques to investigate the neural hemodynamics associated with tactile (TI) and motor imagery (MI). In a study of 15 healthy participants, we found that MI elicited significantly greater hemodynamic responses (HRs) in the precentral area compared to TI, suggesting the involvement of different cortical areas involved in two different types of sensorimotor mental imagery. Concurrently, the HRs in S1 and parietal areas exhibited comparable patterns in both TI and MI. During MI, both motor and somatosensory areas demonstrated comparable HRs. However, in TI, somatosensory activation was observed to be more pronounced. Our results highlight the distinctive neural profiles of motor versus tactile imagery and indicate fNIRS technique to be sensitive for this. This distinction is significant for fundamental understanding of sensorimotor integration and for developing advanced neurotechnologies, including imagery-based brain-computer interfaces (BCIs) that can differentiate between different types of mental imagery.


Subject(s)
Brain Mapping , Hemodynamics , Imagination , Spectroscopy, Near-Infrared , Humans , Spectroscopy, Near-Infrared/methods , Imagination/physiology , Male , Female , Adult , Hemodynamics/physiology , Young Adult , Brain Mapping/methods , Touch Perception/physiology , Touch/physiology , Somatosensory Cortex/physiology , Somatosensory Cortex/diagnostic imaging , Brain/physiology , Brain/diagnostic imaging , Motor Cortex/physiology , Motor Cortex/diagnostic imaging
11.
J Int Soc Sports Nutr ; 21(1): 2409673, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39351657

ABSTRACT

PURPOSE: The effects of coffee ingestion on skeletal muscle microvascular function are not well understood. This study aimed to investigate the acute effects of coffee intake with varying levels of caffeine on skeletal muscle microvascular reactivity at rest and oxygen extraction during maximal incremental exercise in physically active individuals. METHODS: Twenty healthy young male participants were administered coffee with low caffeine (3 mg/kg body weight; LC), high caffeine (6 mg/kg body weight; HC), and placebo (decaf) in different sessions. Skeletal muscle reactivity indexes, including tissue saturation index 10s slope (TSI10) and TSI half time recovery (TSI ½) following 5-minute ischemia were measured at rest and were measured at baseline and post-coffee consumption using near-infrared spectroscopy (NIRS). Post-coffee intake, NIRS was also used to measure microvascular oxygen extraction during exercise via maximal incremental exercise. Peak oxygen consumption and peak power output (Wpeak) were simultaneously evaluated. RESULTS: Post-coffee consumption, TSI10 was significantly higher in the LC condition compared to placebo (p = 0.001) and significantly higher in the HC condition compared to placebo (p < 0.001). However, no difference was detected between LC and HC conditions (p = 0.527). HC condition also showed significant less TSI ½ compared to placebo (p = 0.005). However, no difference was detected for microvascular oxygen extraction during exercise, despite the greater Wpeak found for HC condition (p < 0.001) compared to placebo. CONCLUSION: Coffee ingestion with high caffeine level (6 mg/kg body weight) significantly enhanced skeletal muscle reactivity at rest. However, the improvement of exercise performance with coffee intake is not accompanied by alterations in muscle oxygen extraction.


Subject(s)
Caffeine , Coffee , Cross-Over Studies , Exercise , Muscle, Skeletal , Oxygen Consumption , Rest , Humans , Male , Muscle, Skeletal/blood supply , Muscle, Skeletal/metabolism , Caffeine/administration & dosage , Caffeine/pharmacology , Exercise/physiology , Young Adult , Rest/physiology , Spectroscopy, Near-Infrared , Adult , Microcirculation/drug effects , Double-Blind Method , Oxygen/blood
12.
Eur Heart J Case Rep ; 8(10): ytae504, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39359370

ABSTRACT

Background: Severely calcified lesions are the most significant challenge for percutaneous coronary intervention, exhibiting poor clinical outcomes. Some severely calcified lesions remain untreatable with conventional balloons or even atherectomy devices. Intravascular lithotripsy is a new option for treating severe calcification. Case summary: Herein, we describe a case of ischaemic cardiomyopathy with a thick, circumferential calcified lesion in the proximal and mid-segments of the left anterior descending coronary artery. In the first session, high-pressure balloons, cutting balloons, and rotational atherectomy failed to disrupt the calcification. In the staged additional treatment that was subsequently planned, eight cycles of intravascular lithotripsy created multiple fractures in the deep calcification, resulting in successful stent deployment. The effect of intravascular lithotripsy was observed mainly in calcified areas with lipid components detected using near-infrared spectroscopy-intravascular ultrasound. Discussion: Our report suggests the efficacy of employing a combined strategy of rotational atherectomy with small burrs and intravascular lithotripsy in the treatment of severe calcification with a minimal risk of complications. Our study introduces a novel aspect by utilizing near-infrared spectroscopy-intravascular ultrasound to evaluate calcified lesions before performing intravascular lithotripsy. To our knowledge, there have been no similar reports to date. The effect of intravascular lithotripsy on calcified lesions may be related to the distribution of lipid components and/or heterogeneity within the calcification.

13.
Mol Biol (Mosk) ; 58(2): 314-324, 2024.
Article in Russian | MEDLINE | ID: mdl-39355888

ABSTRACT

Titin is a multidomain protein of striated and smooth muscles of vertebrates. The protein consists of repeating immunoglobulin-like (Ig) and fibronectin-like (FnIII) domains, which are ß-sandwiches with a predominant ß-structure, and also contains disordered regions. In this work, the methods of atomic force microscopy (AFM), X-ray diffraction, and Fourier transform infrared spectroscopy were used to study the morphology and structure of aggregates of rabbit skeletal muscle titin obtained in two different solutions: 0.15 M glycine-KOH, pH 7.0 and 200 mM KCl, 10 mM imidazole, pH 7.0. According to AFM data, skeletal muscle titin formed amorphous aggregates of different morphologies in the above two solutions. Amorphous aggregates of titin formed in a solution containing glycine consisted of much larger particles than aggregates of this protein formed in a solution containing KCl. The "KCl-aggregates" according to AFM data had the form of a "sponge"-like structure, while amorphous "glycine-aggregates" of titin formed "branching" structures. Spectrofluorometry revealed the ability of "glycine-aggregates" of titin to bind to the dye thioflavin T (TT), and X-ray diffraction revealed the presence of one of the elements of the amyloid cross ß-structure, a reflection of ~4.6 Å, in these aggregates. These data indicate that "glycine-aggregates" of titin are amyloid or amyloid-like. No similar structural features were found in "KCl-aggregates" of titin; they also did not show the ability to bind to thioflavin T, indicating the non-amyloid nature of these titin aggregates. Fourier transform infrared spectroscopy revealed differences in the secondary structure of the two types of titin aggregates. The data we obtained demonstrate the features of structural changes during the formation of intermolecular bonds between molecules of the giant titin protein during its aggregation. The data expand the understanding of the process of amyloid protein aggregation.


Subject(s)
Connectin , Microscopy, Atomic Force , Muscle, Skeletal , Protein Aggregates , Connectin/chemistry , Connectin/metabolism , Connectin/genetics , Rabbits , Animals , Muscle, Skeletal/metabolism , Muscle, Skeletal/chemistry , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , Benzothiazoles
14.
Chemphyschem ; : e202400859, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39356243

ABSTRACT

Iron-gall inks, a vital part of our written cultural heritage, are at risk of complete loss due to degradation, a potential loss that we must urgently address. These inks are based on Fe3+-complexes with phenolic compounds, which grow to form a complex network of iron oxyhydroxides. Over time, these black inks turn into brownish tones, with extensive degradation in paper support leading to extensive breaking. The kinetics of iron-gall ink preparation explains the use of iron sulfate, FeSO4, in all ancient recipes to obtain a stable amorphous ink. The novelty of this work shows that a low ratio of Fe3+/polyphenol is a crucial factor in allowing the ink's growth without its degradation. This ratio also prevents the formation of superoxide. This was achieved through a comprehensive research methodology involving spectroscopic techniques in the visible and the near-infrared regions, stopped-flow spectrometry and electrochemical studies.

15.
Physiol Rep ; 12(19): e70076, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39367530

ABSTRACT

Menopause is associated with reduced endothelial-dependent vasodilation and increased cardiovascular disease (CVD) risk. Dietary nitrate, a non-pharmacological approach, may increase vasodilatory capacity consequentially reducing CVD risk. We investigated macro- and microvascular function after acute nitrate supplementation in postmenopausal females (PMF). Vascular function was studied with flow-mediated vasodilation (FMD) and near-infrared post occlusive reactive hyperemia (PORH). Incremental handgrip exercise was performed to investigate blood flow and tissue oxygenation. We hypothesized acute dietary nitrate would not impact resting endothelial measures but would increase post ischemic vasodilation and incremental exercise blood flow. Late-phase PMF (n = 12) participated in a randomized crossover design with 140 mL of nitrate-rich (NR) beetroot juice or nitrate-poor black currant juice. Testing included a 5-min FMD, a 3-min ischemic exercise FMD, and incremental exercise at 10%, 15%, and 20% maximal voluntary contraction to measure blood flow and pressure responses. A p ≤ 0.05 was considered significant. One-way ANOVA indicated lower resting pressures, but no change to FMD, or PORH in either protocol. Two-way repeated measures ANOVA indicated NR supplementation significantly reduced mean arterial pressure at rest and during incremental exercise at all intensities without changes to blood flow. Acute nitrate is effective for resting and exercising blood pressure management in PMF.


Subject(s)
Beta vulgaris , Dietary Supplements , Exercise , Ischemia , Nitrates , Postmenopause , Humans , Female , Nitrates/administration & dosage , Postmenopause/physiology , Pilot Projects , Middle Aged , Exercise/physiology , Ischemia/physiopathology , Vasodilation/drug effects , Fruit and Vegetable Juices , Muscle, Skeletal/drug effects , Muscle, Skeletal/blood supply , Aged , Cross-Over Studies , Hand Strength , Hyperemia/physiopathology , Regional Blood Flow/drug effects
16.
Front Psychiatry ; 15: 1428425, 2024.
Article in English | MEDLINE | ID: mdl-39371911

ABSTRACT

Background: Major depressive disorder (MDD) is associated with deficits in cognitive function, thought to be related to underlying decreased hedonic experiences. Further research is needed to fully elucidate the role of functional brain activity in this relationship. In this study, we investigated the neurofunctional correlate of the interplay between cognitive function and hedonic experiences in medication-free MDD using functional near-infrared spectroscopy (fNIRS). Methods: We examine differences of brain activation corresponding to the verbal fluency test (VFT) between MDD patients and healthy controls (HCs). Fifty-six MDD patients and 35 HCs underwent fMRI scanning while performing the VFT. In exploratory analyses, cognitive performance, as assessed by the Cambridge Neuropsychological Test Automated Battery (CANTAB), four dimensions of hedonic processing (desire, motivation, effort, and consummatory pleasure) measured by the Dimensional Anhedonia Rating Scale (DARS), and relative changes in oxygenated hemoglobin concentration during the VFT were compared across groups. Results: Patients with MDD demonstrated impairments in sustained attention and working memory, accompanied by lower total and subscale scores on the DARS. Compared to healthy controls, MDD patients exhibited reduced activation in the prefrontal cortex (PFC) during the VFT task (t = 2.32 to 4.77, p < 0.001 to 0.02, FDR corrected). DARS motivation, desire, and total scores as well as sustained attention, were positively correlated with activation in the dorsolateral PFC and Broca's area (p < 0.05, FDR corrected). Conclusions: These findings indicate that changes in prefrontal lobe oxygenated hemoglobin levels, a region implicated in hedonic motivation and cognitive function, may serve as potential biomarkers for interventions targeting individuals with MDD. Our results corroborate the clinical consensus that the prefrontal cortex is a primary target for non-invasive neuromodulatory treatments for depression.

17.
Neurophotonics ; 11(4): 045001, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39372120

ABSTRACT

Significance: Motion artifacts are a notorious challenge in the functional near-infrared spectroscopy (fNIRS) field. However, little is known about how to deal with them in resting-state data. Aim: We assessed the impact of motion artifact correction approaches on assessing functional connectivity, using semi-simulated datasets with different percentages and types of motion artifact contamination. Approach: Thirty-five healthy adults underwent a 15-min resting-state acquisition. Semi-simulated datasets were generated by adding spike-like and/or baseline-shift motion artifacts to the real dataset. Fifteen pipelines, employing various correction approaches, were applied to each dataset, and the group correlation matrix was computed. Three metrics were used to test the performance of each approach. Results: When motion artifact contamination was low, various correction approaches were effective. However, with increased contamination, only a few pipelines were reliable. For datasets mostly free of baseline-shift artifacts, discarding contaminated frames after pre-processing was optimal. Conversely, when both spike and baseline-shift artifacts were present, discarding contaminated frames before pre-processing yielded the best results. Conclusions: This study emphasizes the need for customized motion correction approaches as the effectiveness varies with the specific type and amount of motion artifacts present.

18.
Neurophotonics ; 11(4): 045002, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39372121

ABSTRACT

Significance: The ability to monitor cerebral blood flow (CBF) at the bedside is essential to managing critical-care patients with neurological emergencies. Diffuse correlation spectroscopy (DCS) is ideal because it is non-invasive, portable, and inexpensive. We investigated a near-infrared spectroscopy (NIRS) approach for converting DCS measurements into physiological units of blood flow. Aim: Using magnetic resonance imaging perfusion as a reference, we investigated the accuracy of absolute CBF measurements from a bolus-tracking NIRS method that used transient hypoxia as a flow tracer and hypercapnia-induced increases in CBF measured by DCS. Approach: Twelve participants (7 female, 28 ± 6 years) completed a hypercapnia protocol with simultaneous CBF recordings from DCS and arterial spin labeling (ASL). Nine participants completed the transient hypoxia protocol while instrumented with time-resolved NIRS. The estimate of baseline CBF was subsequently used to calibrate hypercapnic DCS data. Results: Moderately strong correlations at baseline ( slope = 0.79 and R 2 = 0.59 ) and during hypercapnia ( slope = 0.90 and R 2 = 0.58 ) were found between CBF values from calibrated DCS and ASL (range 34 to 85 mL / 100 g / min ). Conclusions: Results demonstrated the feasibility of an all-optics approach that can both quantify CBF and perform continuous perfusion monitoring.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 326: 125217, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39369592

ABSTRACT

The Zika disease caused by the Zika virus was declared a Public Health Emergency by the World Health Union (WHO), with microcephaly as the most critical consequence. Aiming to reduce the spread of the virus, biopharmaceutical organizations invest in vaccine research and production, based on multiple platforms. A crescent vaccine production approach is based on virus-like particles (VLP), for not having genetic material in its composition, hypoallergenic and non-mutant character. For bioprocess, it is essential to have means of real-time monitoring, which can be assessed using process analysis techniques such as Near-infrared (NIR) spectroscopy, that can be combined with chemometric methods, like Partial-Least Squares (PLS) and Artificial Neural Networks (ANN) for prediction of biochemical variables. This work proposes a biochemical Zika VLP upstream production at-line monitoring model using NIR spectroscopy comparing sampling conditions (with or without cells), analytical blank (air, ultrapure water), and spectra pre-processing approaches. Seven experiments in a benchtop bioreactor using recombinant baculovirus/Sf9 insect cell platform in serum-free medium were performed to obtain biochemical and spectral data for chemometrics modeling (PLS and ANN), composed by a random data split (80 % calibration, 20 % validation) for cross-validation of the PLS models and 70 % training, 15 % testing, 15 % validation for ANN. The best models generated in the present work presented an average absolute error of 1.59 × 105 cell/mL for density of viable cells, 2.37 % for cell viability, 0.25 g/L for glucose, 0.007 g/L for lactate, 0.138 g/L for glutamine, 0.18 g/L for glutamate, 0,003 g/L for ammonium, and 0.014 g/L for potassium.

20.
J Intensive Care Med ; : 8850666241288141, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39370896

ABSTRACT

AIM & BACKGROUND: Delirium frequently occurs in the acute phase of sepsis and is associated with increased ICU and hospital length of stay, duration of mechanical ventilation, and higher mortality rates. We utilized the Near-Infrared Spectroscopy monitor to measure and compare the regional cerebral oxygen saturation in mechanically ventilated patients of sepsis receiving either dexmedetomidine or propofol sedation and assessed the association between delirium and regional cerebral oxygen saturation. METHODS: A single center prospective randomized control trial conducted over a period of two years, 54 patients were included, equally divided between propofol and dexmedetomidine groups. Patients received a blinded study drug, propofol (10 mg/mL) or dexmedetomidine (5 mcg/mL) via infusion pump according to randomization. Infusion rates were adjusted every 10 min based on weight-based titration tables, aiming for target sedation (RASS -2 to 0). Management components included pain monitoring using the CPOT score and delirium assessment using CAM-ICU score. RESULTS: Dexmedetomidine group showed higher mean regional cerebral oxygen saturation as compared to propofol group (P = .036). No significant differences were found in mechanical ventilation or ICU stay durations, delirium-free days, or sedation cessation reasons. Delirium occurred in 36 patients, with lower mean regional cerebral oxygen saturation as compared to non-delirious patients. CONCLUSION: The dexmedetomidine group had higher regional cerebral oxygen saturation compared to the propofol group. Delirious patients showed lower cerebral oxygen saturation than non-delirious patients, suggesting a link between sedation type, cerebral oxygenation, and delirium.CTRI registration: REF/2021/11/048655 N.

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