scholarly journals In vivo venous blood T1 measurement using inversion recovery true-FISP in children and adults

2010 ◽  
Vol 64 (4) ◽  
pp. 1140-1147 ◽  
Author(s):  
Wen-Chau Wu ◽  
Varsha Jain ◽  
Cheng Li ◽  
Mariel Giannetta ◽  
Hallam Hurt ◽  
...  
Keyword(s):  
Venous Blood ◽  
Inversion Recovery ◽  
True Fisp

STEROID METABOLISM IN THE PERFUSED HUMAN PLACENTA

1978 ◽  
Vol 87 (1) ◽  
pp. 181-191 ◽  
Author(s):  
Alfred S. Wolf ◽  
Klaus A. Musch ◽  
Werner Speidel ◽  
Jürgen R. Strecker ◽  
Christian Lauritzen
Keyword(s):  
Venous Blood ◽  
Placental Lactogen ◽  
Dehydroepiandrosterone Sulphate ◽  
Metabolic Capacity ◽  
Loading Test ◽  
Lower Range ◽  
Group I ◽  
High Concentrations ◽  
Steroid Precursor

ABSTRACT A new model for the perfusion of human term-placentas has been developed for studies on the placental biogenesis of C-18 and C-19 steroids. For viability criteria, the glucose- and oxygen-consumption, regional perfusion control by dye-infusions or scanning after injection of 99Tc-labelled macroparticles, and the histological qualification were chosen. The recycled perfusate was investigated for the steroids oestrone (Oe1), oestradiol-17β (Oe2), oestriol (Oe3), 4-androstene-3,17-dione (A), testosterone (T), and human placental lactogen (HPL) by radioimmunoassay in controls and perfusions with the foetal steroid precursor dehydroepiandrosterone sulphate (DHA-S). In control perfusions, steroid hormones were found in constant ratios (Oe1:Oe2:Oe3:T:A = 30:1.5:100:0.35:1). Following the administration of 10 mg DHA-S for testing the metabolic capacity of the organ, high concentrations of Oe1 (90–720 ng/ml = 250–3970 % as compared to 100% pre-injection values) were found, shortly preceded by a rapid increase of A (66–1000 ng/ml = 100–16 000 %). A typical surge of T (5.3–147 ng/ml = 265–4640 %) preceded the normally slower increment of Oe2 (22–220 ng/ml = 1570–4330 %). The concentrations of Oe3 and HPL remained nearly unchanged. From different steroid patterns after DHA-S-load, two distinct responses of term-placentas could be differentiated: Group I (n=12) showed high concentrations of Oe1 (3200 ± 940 %), a small increase of T (1020 ± 500%), as well as low and delayed values of Oe2 (1660 ± 450%). In Group II (n = 5), values were high for T (3160 ± 1020%) and Oe2 (3300 ± 1110%), whereas Oe1 was found in a lower range (508 ± 302%). In contrast to in vivo findings in maternal venous blood after DHS-S injection to the mother, oestrone was found in perfusions as the main oestrogen fraction from DHA-S. Thus, the analysis of such metabolic differences might be of help in the interpretation of complex results from the DHA-S-loading test.

scholarly journals Supervised Machine Learning Methods and Hyperspectral Imaging Techniques Jointly Applied for Brain Cancer Classification

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3827
Author(s):  
Gemma Urbanos ◽  
Alberto Martín ◽  
Guillermo Vázquez ◽  
Marta Villanueva ◽  
Manuel Villa ◽  
...  
Keyword(s):  
Machine Learning ◽  
Blood Vessel ◽  
Hyperspectral Imaging ◽  
Imaging Techniques ◽  
Venous Blood ◽  
Healthy Tissue ◽  
Supervised Machine Learning ◽  
Support Vector ◽  
Arterial Blood

Hyperspectral imaging techniques (HSI) do not require contact with patients and are non-ionizing as well as non-invasive. As a consequence, they have been extensively applied in the medical field. HSI is being combined with machine learning (ML) processes to obtain models to assist in diagnosis. In particular, the combination of these techniques has proven to be a reliable aid in the differentiation of healthy and tumor tissue during brain tumor surgery. ML algorithms such as support vector machine (SVM), random forest (RF) and convolutional neural networks (CNN) are used to make predictions and provide in-vivo visualizations that may assist neurosurgeons in being more precise, hence reducing damages to healthy tissue. In this work, thirteen in-vivo hyperspectral images from twelve different patients with high-grade gliomas (grade III and IV) have been selected to train SVM, RF and CNN classifiers. Five different classes have been defined during the experiments: healthy tissue, tumor, venous blood vessel, arterial blood vessel and dura mater. Overall accuracy (OACC) results vary from 60% to 95% depending on the training conditions. Finally, as far as the contribution of each band to the OACC is concerned, the results obtained in this work are 3.81 times greater than those reported in the literature.

The procoagulant effects of factor V Leiden may be balanced against decreased levels of factor V and do not reflect in vivo thrombin formation in newborns

2006 ◽  
Vol 95 (03) ◽  
pp. 434-440 ◽  
Author(s):  
Satu Hyytiäinen ◽  
Ulla Wartiovaara-Kautto ◽  
Veli-Matti Ulander ◽  
Risto Kaaja ◽  
Markku Heikinheimo ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Platelet Rich Plasma ◽  
Venous Blood ◽  
Factor V Leiden ◽  
Factor V ◽  
Cord Plasma ◽  
Adult Plasma ◽  
Thrombin Formation

SummaryThrombin regulation in newborns remains incompletely understood.We studied tissue factor-initiated thrombin formation in cord plasma in vitro, and the effects of Factor VLeiden (FVL) heterozygosity on thrombin regulation both in vitro and in vivo in newborns. Pregnant women with known thrombophilia (n=27) were enrolled in the study. Cord blood and venous blood at the age of 14 days were collected from 11 FVL heterozygous newborns (FVL-positive) and from 16 FVL-negative newborns. Prothrombin fragment F1+2 and coagulation factors were measured. Tissue factor-initiated thrombin formation was studied in cord platelet-poor plasma (PPP) of FVL-negative and -positive newborns, and in both PPP and platelet-rich plasma (PRP) of healthy controls. The endogenous thrombin potential (ETP) in cord PPP or PRP was ∼60% of that in adult plasma, while thrombin formation started ∼55% and ∼40% earlier in cord PPP and PRP, respectively. Further, in FVL-positive newborns thrombin formation started significantly earlier than in FVL-negative newborns. Exogenous activated protein C (APC) decreased ETP significantly more in cord than in adult PRP. In FVL-negative cord plasma 5nM APC decreased ETP by 17.4±3.5% (mean±SEM) compared with only 3.5±3.8% in FVL-positive cord plasma (p=0.01). FVL-positive newborns showed similar levels of F1+2 but significantly decreased levels of factor V compared with FVL negative newborns both in cord plasma (FV 0.82±0.07 U/ml vs. 0.98±0.05 U/ml, p=0.03) and at the age of two weeks (FV 1.15±0.04 U/ml vs. 1.32±0.05 U/ml, p=0.03). In conclusion, newborn plasma showed more rapid thrombin formation and enhanced sensitivity to APC compared with adult plasma. FVL conveyed APC resistance and a procoagulant effect in newborn plasma. Lack of elevated F1+2 levels in FVL-positive infants, however, suggested the existence of balancing mechanisms; one could be the observed lower level of factor V in FVL heterozygous newborns.

Effects of PACAP1–27 on the canine endocrine pancreas in vivo: interaction with cholinergic mechanism

2003 ◽  
Vol 81 (7) ◽  
pp. 720-729 ◽  
Author(s):  
Nobuharu Yamaguchi ◽  
Tamar Rita Minassian ◽  
Sanae Yamaguchi
Keyword(s):  
Endocrine Pancreas ◽  
Venous Blood ◽  
Insulin Response ◽  
Glucagon Secretion ◽  
Venous Blood Flow ◽  
Dependent Manner ◽  
Cholinergic Mechanism ◽  
Insulin And Glucagon Secretion ◽  
Anesthetized Dogs

The aim of the present study was to characterize the effects of pituitary adenylate cyclase activating polypeptide (PACAP) on the endocrine pancreas in anesthetized dogs. PACAP1–27 and a PACAP receptor (PAC1) blocker, PACAP6–27, were locally administered to the pancreas. PACAP1–27 (0.005–5 μg) increased basal insulin and glucagon secretion in a dose-dependent manner. PACAP6–27 (200 μg) blocked the glucagon response to PACAP1–27 (0.5 μg) by about 80%, while the insulin response remained unchanged. With a higher dose of PACAP6–27 (500 μg), both responses to PACAP1–27 were inhibited by more than 80%. In the presence of atropine with an equivalent dose (128.2 μg) of PACAP6–27 (500 μg) on a molar basis, the insulin response to PACAP1–27 was diminished by about 20%, while the glucagon response was enhanced by about 80%. The PACAP1–27-induced increase in pancreatic venous blood flow was blocked by PACAP6–27 but not by atropine. The study suggests that the endocrine secretagogue effect of PACAP1–27 is primarily mediated by the PAC1 receptor, and that PACAP1–27 may interact with muscarinic receptor function in PACAP-induced insulin and glucagon secretion in the canine pancreas in vivo.Key words: atropine, PACAP, PAC1, muscarinic, interaction.

scholarly journals Intestinal Permeability Assays: a Review

2021 ◽  
Vol 31 (1) ◽  
pp. 20-30
Author(s):  
A. A. Iakupova ◽  
S. R. Abdulkhakov ◽  
R. K. Zalyalov ◽  
A. G. Safin ◽  
R. A. Abdulkhakov
Keyword(s):  
Intestinal Permeability ◽  
Ex Vivo ◽  
Venous Blood ◽  
Intestinal Barrier ◽  
Intestinal Lumen ◽  
Alcoholic Fatty Liver ◽  
Key Points ◽  
Assessment Techniques ◽  
Portal Venous Blood

Aim. A literature review of intestinal permeability assessment techniques.Key points. The intestinal barrier is a functional entity separating the intestinal lumen and internal body, and intestinal permeability is a measure of the barrier functionality. The intestinal barrier integrity and permeability assays differ by the application setting (in vivo or ex vivo), subject (human or animal), marker molecules used to assess permeability (ions, various size carbohydrates, macromolecules, antigens, bacterial products and bacteria), biomaterial for the marker concentration assays (peripheral blood, portal venous blood, urine, stool). Despite a great variety of methods for assessing intestinal permeability, their clinical application requires further studies due to a lack of standardisation, the complexity of selected techniques and occasional limited reliability of results.Conclusion. Further investigation and improvement of intestinal permeability assays is required. The assay and result standardisation will facilitate practice in functional and organic intestinal diseases, as well as allergies, diabetes mellitus, non-alcoholic fatty liver disease and some other illnesses.

scholarly journals Testicular microvascular flow is altered in Klinefelter syndrome and predicts circulating testosterone

2021 ◽  
Author(s):  
Francesco Carlomagno ◽  
Carlotta Pozza ◽  
Marta Tenuta ◽  
Riccardo Pofi ◽  
Luigi Tarani ◽  
...  
Keyword(s):  
Blood Flow ◽  
Klinefelter Syndrome ◽  
Mean Transit Time ◽  
Venous Blood ◽  
Experimental Studies ◽  
Principal Component ◽  
Endocrine Function ◽  
Venous Blood Flow ◽  
Testicular Blood Flow

ABSTRACTContextExperimental studies on Klinefelter syndrome (KS) reported increased intratesticular testosterone (T) levels coexisting with reduced circulating levels. Abnormalities in testicular microcirculation have been claimed; however, no studies investigated in vivo testicular blood flow dynamics in humans with KS.ObjectiveTo analyze the testicular microcirculation in KS by contrast-enhanced ultrasonography (CEUS) and correlate vascular parameters with endocrine function.Design and SettingProspective study. University Settings.Patients51 testicular scans, 17 testes from 10 T-naïve subjects with KS and 34 testes from age-matched eugonadal men (CNT) who underwent CEUS for incidental nonpalpable testicular lesions.Main OutcomesCEUS kinetic parameters.ResultsCEUS revealed slower testicular perfusion kinetics in subjects with KS than in age-matched CNT. Specifically, the wash-in time (Tin, p = 0.008), mean transit time (MTT, p = 0.008), time to peak (TTP, p < 0.001), and washout time (Tout 50%, p = 0.008) were all prolonged. Faster testicular blood flow was associated with higher total T levels. Principal component analysis and multiple linear regression analyses confirmed the findings, and supported a role for reduced venous blood flow as independent predictor of total T levels.ConclusionsTesticular venous blood flow is altered in KS and independently predicts T peripheral release.

In Vivo CO2 Buffer Curves of Arterial and Mixed Venous Blood

1971 ◽  
Vol 137 (1) ◽  
pp. 237-242 ◽  
Author(s):  
A. C. Garcia ◽  
Y. L. Lai ◽  
B. A. Attebery ◽  
E. B. Brown
Keyword(s):  
Venous Blood ◽  
Mixed Venous Blood ◽  
Mixed Venous

Reappraisal of H2S/sulfide concentration in vertebrate blood and its potential significance in ischemic preconditioning and vascular signaling

2008 ◽  
Vol 294 (6) ◽  
pp. R1930-R1937 ◽  
Author(s):  
Nathan L. Whitfield ◽  
Edward L. Kreimier ◽  
Francys C. Verdial ◽  
Nini Skovgaard ◽  
Kenneth R. Olson
Keyword(s):  
Ischemic Preconditioning ◽  
Baseline Level ◽  
Venous Blood ◽  
Sulfide Concentration ◽  
Potential Significance ◽  
Aortic Blood ◽  
Total Sulfide ◽  
Series Of Experiments

Hydrogen sulfide (H2S) is rapidly emerging as a biologically significant signaling molecule. Studies published before 2000 report low or undetectable H2S (usually as total sulfide) levels in blood or plasma, whereas recent work has reported sulfide concentrations between 10 and 300 μM, suggesting it acts as a circulating signal. In the first series of experiments, we used a recently developed polarographic sensor to measure the baseline level of endogenous H2S gas and turnover of exogenous H2S gas in real time in blood from numerous animals, including lamprey, trout, mouse, rat, pig, and cow. We found that, contrary to recent reports, H2S gas was essentially undetectable (<100 nM total sulfide) in all animals. Furthermore, exogenous sulfide was rapidly removed from blood, plasma, or 5% bovine serum albumin in vitro and from intact trout in vivo. To determine if blood H2S could transiently increase, we measured oxygen-dependent H2S production by trout hearts in vitro and in vivo. H2S has been shown to mediate ischemic preconditioning (IPC) in mammals. IPC is present in trout and, unlike mammals, the trout myocardium obtains its oxygen from relatively hypoxic systemic venous blood. In vitro, myocardial H2S production was inversely related to Po2, whereas we failed to detect H2S in ventral aortic blood from either normoxic or hypoxic fish in vivo. These results provide an autocrine or paracrine mechanism for myocardial coupling of hypoxia to H2S in IPC, i.e., oxygen sensing, but they fail to provide any evidence that H2S signaling is mediated by the circulation.

In Vivo Analysis of Gas Transport in Arterial and Venous Blood of the Sea Lamprey Petromyzon Marinus

1992 ◽  
Vol 169 (1) ◽  
pp. 105-119
Author(s):  
B. L. TUFTS ◽  
B. BAGATTO ◽  
B. CAMERON
Keyword(s):  
Partial Pressure ◽  
Whole Blood ◽  
Venous Blood ◽  
Recovery Period ◽  
Co2 Concentration ◽  
Extracellular Acidosis ◽  
Arterial Blood ◽  
Sea Lampreys ◽  
In Vivo Analysis

Exercise in sea lampreys resulted in a significant decrease in the extracellular pH (pHe) in both arterial and venous blood. At rest, the erythrocyte pH (pHi) of venous blood was significantly greater than the pHi of arterial blood. Despite the considerable extracellular acidosis after exercise, both arterial and venous pHi were maintained throughout the recovery period. In the venous blood, there was a reversal of the pH gradient (ΔpH) across the erythrocyte membrane immediately after exercise. Exercise also resulted in significant reductions in the partial pressure of oxygen and hemoglobin oxygen-carriage and a significant increase in the partial pressure of CO2 in arterial and venous blood. Although the total CO2 concentration of the plasma decreased after exercise, erythrocyte total CO2 concentrations (CCOCO2,i) increased. In venous blood, the CCOCO2,i immediately after exercise was double the resting value. At rest, partitioning of the total CO2 content between plasma and erythrocytes indicated that 16 % and 22 % of the total CO2 could be attributed to the erythrocytes in arterial and venous whole blood, respectively. After exercise, these percentages increased to 25% (arterial) and 38% (venous). Changes in CCOCO2,i accounted for 62% of the arteriovenous difference in whole-blood total CO2 at rest. This increased to 78% immediately after exercise. Thus, unlike other vertebrates, CO2 transport in the lamprey in vivo is largely dependent on erythrocyte CO2-carriage.

Cortical involvement and leptomeningeal inflammation in myelin oligodendrocyte glycoprotein antibody disease: A three-dimensional fluid-attenuated inversion recovery MRI study

2021 ◽  
pp. 135245852110343
Author(s):  
Dimitrios Tzanetakos ◽  
John S Tzartos ◽  
Aigli G Vakrakou ◽  
Marianthi Breza ◽  
Georgios Velonakis ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Median Number ◽  
Myelin Oligodendrocyte Glycoprotein ◽  
Inversion Recovery ◽  
Cortical Lesion ◽  
Mri Findings ◽  
Meningeal Inflammation ◽  
Fluid Attenuated Inversion Recovery ◽  
3D Flair

Background: Cortical demyelination and meningeal inflammation have been detected neuropathologically in multiple sclerosis (MS) and recently in myelin oligodendrocyte glycoprotein antibody disease (MOGAD). Objectives: To assess in vivo cortical and leptomeningeal involvement in MOGAD. Methods: We prospectively evaluated 11 MOGAD and 12 relapsing-remitting MS (RRMS) patients combining three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) and 3D-T1-weighted (3D-T1w) sequences at 3-Tesla magnetic resonance imaging (MRI). Leptomeningeal contrast enhancement (LMCE) was assessed on 3D-FLAIR post-gadolinium (3D-FLAIRGd). Cerebral cortical lesions (CCLs) were classified as either intracortical–subpial (IC–SP) or leukocortical (LC). Results: CCLs were present in 8/11 MOGAD and 12/12 RRMS patients, with the number of CCLs being significantly lower in MOGAD (median (interquartile range (IQR)) 3 (0.5–4) vs 12 (4.75–19), p = 0.0032). In MOGAD, IC–SP lesions were slightly more prevalent than LC lesions (2 (0–2.5) vs 1 (0–2), p = 0.6579); whereas in RRMS, IC–SP lesions were less prevalent than LC lesions (3.5 (2.75–5.5) vs 9 (2–12.75), p = 0.27). LMCE was observed in 3/11 MOGAD and 1/12 RRMS patients; MOGAD with LMCE showed an increased median number of CCLs compared with MOGAD without LMCE (8 (4–9) vs 2.5 (0.75–3.25), p = 0.34). No correlation was observed between MOGAD MRI findings and (a) MOGAD duration, (b) serum MOG-immunoglobulin G1 titers, and (c) oligoclonal band presence. Conclusion: We described cortical lesion topography and detected for the first time LMCE using 3D-FLAIRGd sequences in MOGAD patients.

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