Total Hemoglobin Concentration Research Articles

Toxicity assessment of beta-cyfluthrin with impact on haematology of fish, Channa punctatus

Âeta-cyfluthrin, a synthetic pyrethroid pesticide, is commonly used in agriculture for pest control and as household insecticide. It is relatively safe to mammals and birds but highly toxic to non-target aquatic organisms including fish. The 96- hour LC50 was determined using standard toxicity assessment tests. Alterations in haematological parameters were recorded after exposure to two sublethal concentrations of beta-cyfluthrin for a period of 15 and 30 days.The results showed a significant decrease in total erythrocyte count, haemoglobin concentration, haematocrit percentage and increase in total leucocyte count in exposed groups.The results of present study indicate a significant toxicological impact of beta-cyfluthrinon in Channa punctatus with marked alterations in haematological parameters.

Machine Learning Distinguishes Familiar from Unfamiliar Pairs of Subjects Performing an Eye Contact Task: A Systemic Physiology Augmented Functional Near-Infrared Spectroscopy Hyperscanning Study.

Eye contact is an important aspect of human communication and social interactions. Changes in brain and systemic physiological activity associated with interactions between humans can be measured with systemic physiology augmented functional near-infrared spectroscopy (SPA-fNIRS) hyperscanning, enabling inter-brain and inter-body synchronisation to be determined. In a previous study, we found that pairs of subjects that are socially connected show higher brain and body synchrony. To enable a deeper understanding, our aim was to build and automatically detect the best set of features to distinguish between two different groups (familiar and unfamiliar pairs). We defined several features based on the Spearman correlation and wavelet transform coherence (WTC) of biosignals measured on 23 pairs of subjects (13 familiar and 10 unfamiliar pairs) during eye contact for 10 min. Additional custom features that identify the maximum brain-to-body coupling instants between pairs were generated. After testing on combinations of different feature extraction methods, four subsets of features with the strongest discrimination power were taken into account to train a decision tree (DT) machine learning (ML) algorithm. We have obtained 95.65% classification accuracy using a leave-one-out cross-validation. The coupling features which represent the two maximum mean values resulting from the sum of 7 time-dependent WTC signals (oxyhaemoglobin concentration of the right prefrontal region, total haemoglobin concentration of the left and right prefrontal region, heart rate, electrodermal activity on the left and right wrist, and skin temperature on the right wrist) played an essential role in the classification accuracy. Training the DT-ML algorithm with combined brain and systemic physiology data provided higher accuracy than training it only with brain or systemic data alone. The results demonstrate the power of the SPA-fNIRS hyperscanning approach and the potential in applying ML to investigate the strength of social bonds in a wide range of social interaction contexts.

Development and Design of Flexible Sensors Used in Pressure-Monitoring Sports Pants for Human Knee Joints

Flexible pressure sensors are being used widely in sports and human-health monitoring. The knee joint is one of the organs with the highest injury rate while running. By optimizing the structural design of sports pants, the lower limbs can be compressed appropriately to protect the knee joint and improve exercise efficiency. The point of innovation lies in the removable flexible pressure sensors implanted in these leggings developed to monitor the three-dimensional force on the knee in real time. Combined with data analysis, this can provide information to wearers while exercising and to the middle-aged and elderly to prevent knee-strain problems. The experimental results showed that the pressure values of the left and right knee joints measured using the flexible pressure sensors on the leggings in real time and those obtained using the AMI3037-5s Airbag pressure tester were accompanied by F-values and t-test statistical probability values greater than 0.05. This indicates that there was no significant difference between the two values, reflecting the credibility of the flexible pressure-monitoring data. The oxygen saturation and total hemoglobin content of a subjects’ legs after exercising were higher than those before exercising, indicating that the leggings performed well in terms of fatigue relief. The subjects’ body surface temperature, when exercising, changed steadily and dropped gradually in the later stage, indicating that the leggings perform well with respect to thermal and moisture comfort. Flexible sensing technology has promising application prospects in wearable smart clothing in future, particularly in the sports and health fields.

Preclinical Development of EDIT301, an Autologous Cell Therapy Comprising AsCas12a-RNP Modified Mobilized Peripheral Blood-CD34 + Cells for the Potential Treatment of Transfusion Dependent Beta Thalassemia

Beta thalassemia is one of the most common recessive hematological disorders in the world with more than 200 mutations identified to date. These mutations reduce or completely abrogate beta globin expression. As beta globin pairs with alpha globin to form adult hemoglobin (HbA, α2β2), reduced or absent beta globin results in excessive alpha globin chains, which form toxic aggregates. These aggregates cause maturation blockade and premature death of erythroid precursors, and hemolysis of red blood cells (RBC), leading to varying degrees of anemia. Patients with the most severe form of beta thalassemia, namely beta thalassemia major, are transfusion-dependent, i.e., requiring life-long RBC transfusions accompanied by the burden of iron chelation therapy.EDIT-301 is an experimental autologous cell therapy in which CD34 + cells are genetically modified to promote gamma globin expression. EDIT-301 is currently in clinical development for sickle cell disease, and IND enabling stage for transfusion-dependent beta thalassemia (TDT). Gamma globin decreases the alpha to beta globin chain imbalance in beta thalassemia by pairing with the over-abundant alpha globin chains to form fetal hemoglobin (HbF, α2γ2). Gamma globin induction, and consequently HbF induction, for EDIT-301 is achieved through AsCas12a ribonucleoprotein (RNP)-mediated editing of the distal CCAAT box region of the HBG1 and HBG2 promoters, where naturally occurring hereditary persistence of fetal hemoglobin (HFPH) mutations exist. We chose this target over BCL11A based on previous preclinical data demonstrating that BCL11A editing reduces erythroid output in NBSGW mice. An engineered AsCas12a RNP edits the HBG1 and HBG2 promoter distal CCAAT box with high efficiency and specificity. We have previously shown that on-target editing of >80% was achieved in mobilized peripheral blood (mPB) CD34 + cells from normal donors with no detectable off-target editing both at research scale and at clinical manufacturing scale. Edited normal donor CD34 + cells led to long-term, polyclonal, multilineage engraftment without lineage skewing in immunocompromised mice and sustained robust HbF production in their erythroid progeny.To test whether EDIT-301 may be an efficacious therapy for TDT, mPB CD34 + cells from individuals with TDT were electroporated with the engineered AsCas12a RNP targeting the HBG1 and HBG2 promoters. AsCas12a RNP edited mPB CD34 + cells from individuals with TDT as efficiently as CD34 + cells from normal donors. Importantly, EDIT-301 has the potential to address the underlying pathophysiology of TDT, i.e., the maturation blockade and premature death of erythroid precursors. Erythroid differentiation of edited beta thalassemia CD34 + cells showed significant improvement in erythroid maturation and health. Specifically, ~70% edited erythroblasts reached late erythroblast stage compared to ~53% unedited erythroblasts; ~56% edited erythroid cells underwent terminal maturation and enucleated compared to ~28% of unedited erythroid cells; and non-viable erythroblasts decreased from ~33% to ~22% after editing. The improved erythropoiesis was accompanied by significantly increased total hemoglobin content per cell. These data strongly support that editing of the HBG1 and HBG2 promoter CCAAT box using engineered AsCas12a RNP can reverse the dyserythropoiesis associated with beta thalassemia and increase the hemoglobin production.In summary, we have provided strong preclinical data supporting the development of EDIT-301 for the treatment of TDT. Edited mPB CD34 + cells retained their ability to engraft without lineage skewing, resulted in robust HbF induction long-term, improved erythropoiesis, and increased hemoglobin content in TDT erythroid cells. These data support that a single administration of EDIT-301 may have the potential to safely and effectively reverse dyserythropoiesis and ameliorate anemia in individuals with TDT long-term. Clinical studies to demonstrate the safety and efficacy of EDIT-301 in the treatment of TDT are currently being planned. DisclosuresSousa: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Janoudi: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. deDreuzy: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Shearman: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Zhang: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Chang: Editas Medicine: Current Employment, Current equity holder in publicly-traded company.

Cerebral and muscle near-infrared spectroscopy during lower-limb muscle activity - volitional and neuromuscular electrical stimulation.

Chronic venous insufficiency (CVI) can lead to blood clotting in the deep veins of the legs, a disease known as deep vein thrombosis. An estimated 40 percent of people in the United States have venous insufficiency that may be ameliorated with neuromuscular electrical stimulation (NMES). Near-infrared spectroscopy (NIRS) is a non-invasive optical imaging method for monitoring hemodynamics. NIRS, being an optical technique has no stimulation artefact, can be combined with NMES for theranostics application. In this study, we combined muscle NIRS (mNIRS) with electromyogram (EMG) of the calf muscles to detect blood volume changes (based on total hemoglobin concentration) in the muscle during volitional tiptoe movements at different frequencies. Also, blood volume changes were measured during NMES (using the geko™ device) at different device settings. In the mNIRS+NMES study, we also measured the cerebral hemodynamics using functional NIRS (fNIRS). The mNIRS was conducted using a frequency domain (FD) method (called FDNIRS) that used a multi-distance method to isolate muscle hemodynamics. FDNIRS-EMG study in ten healthy humans found a statistically significant (p<0.05) effect of the tiptoe frequencies on the EMG magnitude (and power) that increased with tiptoe frequency. Also, the muscle blood volume (standing/rest) decreased (p<0.01) with increasing tiptoe frequency and increasing NMES intensity that was statistically significantly (p<0.05) different between males and females. Moreover, increasing NMES intensity led to a statistically significant (p<0.01) increase in the cerebral blood volume - measured with fNIRS. Therefore, combined mNIRS and fNIRS with NMES can provide a theranostics application for brain+muscle in CVI.

Monitoring and Evaluation of Emotion Regulation by Aerobic Exercise and Motor Imagery Based on Functional Near-Infrared Spectroscopy.

Objective: We sought to effectively alleviate the emotion of individuals with anxiety and depression, and explore the effects of aerobic exercise on their emotion regulation. Functional near-infrared spectroscopy (fNIRS) brain imaging technology is used to monitor and evaluate the process of aerobic exercise and imagination that regulates emotion.Approach:Thirty participants were scored by the state-trait anxiety inventory (STAI) and profile of mood states (POMS), and fNIRS images were collected before, after, and during aerobic exercise and motor imagery. Then, the oxygenated hemoglobin (HbO), deoxygenated hemoglobin (HbR), and total hemoglobin (HbT) concentrations and their average value were calculated, and the ratio of HbO concentration in the left and right frontal lobes was determined. Spearman's correlation coefficient was used to calculate the correlation between variations in the average scores of the two scales and in blood oxygen concentrations.Results: In comparison with motor imagery, STAI, and POMS scores decreased after 20 min of aerobic exercise. The prefrontal cortex had asymmetry and laterality (with the left side being dominant in emotion regulation). The increase in hemoglobin concentration recorded by fNIRS was negatively correlated with STAI and POMS scores. Aerobic exercise has a good effect on emotion regulation.Significance:The study showed that portable fNIRS could be effectively used for monitoring and evaluating emotion regulation by aerobic exercise. This study is expected to provide ideas for constructing fNIRS-based online real-time monitoring and evaluation of emotion regulation by aerobic exercise.

Performance Assessment of a Commercial Continuous-Wave Near-Infrared Spectroscopy Tissue Oximeter for Suitability for Use in an International, Multi-Center Clinical Trial.

Despite the wide range of clinical and research applications, the reliability of the absolute oxygenation measurements of continuous wave near-infrared spectroscopy sensors is often questioned, partially due to issues of standardization. In this study, we have compared the performances of 13 units of a continuous wave near-infrared spectroscopy device (PortaMon, Artinis Medical Systems, NL) to test their suitability for being used in the HEMOCOVID-19 clinical trial in 10 medical centers around the world. Detailed phantom and in vivo tests were employed to measure the precision and reproducibility of measurements of local blood oxygen saturation and total hemoglobin concentration under different conditions: for different devices used, different operators, for probe repositioning over the same location, and over time (hours/days/months). We have detected systematic differences between devices when measuring phantoms (inter-device variability, <4%), which were larger than the intra-device variability (<1%). This intrinsic variability is in addition to the variability during in vivo measurements on the forearm muscle resulting from errors in probe positioning and intrinsic physiological noise (<9%), which was also larger than the inter-device differences (<3%) during the same test. Lastly, we have tested the reproducibility of the protocol of the HEMOCOVID-19 clinical trial; that is, forearm muscle oxygenation monitoring during vascular occlusion tests over days. Overall, our conclusion is that these devices can be used in multi-center trials but care must be taken to characterize, follow-up, and statistically account for inter-device variability.

Grey-box modeling and hypothesis testing of functional near-infrared spectroscopy-based cerebrovascular reactivity to anodal high-definition tDCS in healthy humans

Transcranial direct current stimulation (tDCS) has been shown to evoke hemodynamics response; however, the mechanisms have not been investigated systematically using systems biology approaches. Our study presents a grey-box linear model that was developed from a physiologically detailed multi-compartmental neurovascular unit model consisting of the vascular smooth muscle, perivascular space, synaptic space, and astrocyte glial cell. Then, model linearization was performed on the physiologically detailed nonlinear model to find appropriate complexity (Akaike information criterion) to fit functional near-infrared spectroscopy (fNIRS) based measure of blood volume changes, called cerebrovascular reactivity (CVR), to high-definition (HD) tDCS. The grey-box linear model was applied on the fNIRS-based CVR during the first 150 seconds of anodal HD-tDCS in eleven healthy humans. The grey-box linear models for each of the four nested pathways starting from tDCS scalp current density that perturbed synaptic potassium released from active neurons for Pathway 1, astrocytic transmembrane current for Pathway 2, perivascular potassium concentration for Pathway 3, and voltage-gated ion channel current on the smooth muscle cell for Pathway 4 were fitted to the total hemoglobin concentration (tHb) changes from optodes in the vicinity of 4x1 HD-tDCS electrodes as well as on the contralateral sensorimotor cortex. We found that the tDCS perturbation Pathway 3 presented the least mean square error (MSE, median <2.5%) and the lowest Akaike information criterion (AIC, median -1.726) from the individual grey-box linear model fitting at the targeted-region. Then, minimal realization transfer function with reduced-order approximations of the grey-box model pathways was fitted to the ensemble average tHb time series. Again, Pathway 3 with nine poles and two zeros (all free parameters), provided the best Goodness of Fit of 0.0078 for Chi-Square difference test of nested pathways. Therefore, our study provided a systems biology approach to investigate the initial transient hemodynamic response to tDCS based on fNIRS tHb data. Future studies need to investigate the steady-state responses, including steady-state oscillations found to be driven by calcium dynamics, where transcranial alternating current stimulation may provide frequency-dependent physiological entrainment for system identification. We postulate that such a mechanistic understanding from system identification of the hemodynamics response to transcranial electrical stimulation can facilitate adequate delivery of the current density to the neurovascular tissue under simultaneous portable imaging in various cerebrovascular diseases.

Acute effects of exercise on cerebrovascular response and cognitive performance in individuals with stable coronary heart disease

BackgroundIndividuals with coronary heart disease (CHD) exhibit cognitive deficits and cerebrovascular dysfunctions, and are at higher risk of developing dementia. Cognitive function in individuals with CHD has never been studied during acute aerobic exercise. Given the increasing popularity of training at high peak power output (PPO), its impact on cerebrovascular and cognitive functions in individuals with CHD should be further studied. MethodThirty-eight individuals with CHD and 16 healthy controls completed two exercise bouts at 30% and 70% of their individualized PPO on an ergocycle while performing a cognitive task including non-executive and executive conditions. Variations of oxy- deoxy-hemoglobin, and total hemoglobin concentrations were measured on left prefrontal cortex at both PPO using near-infrared spectroscopy. ResultsCognitive task performances were equivalent between groups at all intensity levels. Individuals with CHD exhibited larger variation of deoxyhemoglobin in the executive condition and larger variation in total hemoglobin concentration in all task conditions compared to healthy controls at 70% of PPO. ConclusionExercising at high intensity seems to have a larger impact on cerebral blood volume in CHD patients compared to healthy age-matched controls. Higher exercise intensity has negative impacts on cerebral blood volume variations during a cognitive task in CHD patients and could potentially lead to other neurocognitive dysfunctions. Other studies are needed to determine if a cognitive task administered during an exercise test could help identify individuals with CHD at higher risk of developing cognitive decline.

Cerebral hemodynamics during neonatal transition according to mode of delivery

Cerebral haemodynamics during the immediate transition period in neonates may differ depending on whether delivery is vaginal or by caesarean section. However, these differences have never been confirmed by near-infrared time-resolved spectroscopy (TRS). Therefore, the purpose of this study was to compare cerebral blood volume (CBV) and cerebral haemoglobin oxygen saturation (ScO2) between healthy term neonates by mode of delivery. Subjects were 31 healthy term neonates who did not require resuscitation. Thirteen neonates were delivered vaginally (VD group) and 18 were delivered by elective caesarean section (CS group). Absolute oxyhaemoglobin, deoxyhaemoglobin, and total haemoglobin concentrations were measured continuously by TRS; oxyHb × 100/totalHb (ScO2) (%) and CBV (mL/100 g brain tissue) were also calculated. Measurements were started as soon as possible after birth, obtained from 1 to 2 min after birth, and continued until 15 min after birth. CBV was significantly higher in the VD group than in the CS group in the 4 min after birth but not thereafter. There were no significant between-group differences in ScO2 and SpO2. These findings indicate that there is a difference in cerebral haemodynamic patterns in the first 4 min after delivery between term neonates by mode of delivery when CBV is monitored by TRS.

Impact of brown adipose tissue vascular density on body adiposity in healthy Japanese infants and children.

Background and ObjectiveThe importance of brown adipose tissue (BAT) is well recognized in healthy infants and children. However, information regarding age‐related changes in BAT vascular density (BAT‐d) and the impact of BAT‐d on body adiposity are lacking. This study aimed to evaluate the normal values of BAT‐d, factors influencing BAT‐d, and the impact of BAT‐d on body adiposity in healthy infants and children.MethodsThis study included 240 participants (127 girls and 113 boys) aged 1 month to 5 years. The tissue total hemoglobin concentration in the supraclavicular region adjusted according to the subcutaneous adipose tissue thickness (SAT) ([total‐Hb‐Adj]sup) as BAT‐d. SAT in the deltoid and interscapular regions (SATdel+int), the Kaup index (body weight [g]/height or length [cm]/height or length [cm] × 10) as body adiposity, and fertilization season were also measured.ResultsThe [total‐Hb‐Adj]sup of boys was higher than that of girls (r = 0.277, p = 0.009). Younger children had a significantly higher Kaup index (r = 0.495, p < 0.001) and SATdel+int (r = 0.614, p < 0.001) than older children. Children who had higher [total‐Hb‐Adj]sup had a significantly lower Kaup index (r = 0.495, p = 0.037) and SATdel+int (r = 0.614, p < 0.001).ConclusionThe [total‐Hb‐Adj]sup, as a parameter of BAT‐d, is negatively correlated with body adiposity in children aged 1 month to 5 years, and BAT might affect human obesity to a much greater extent than expected. To prevent or treat obesity in early childhood, the level of BAT‐d should be considered when using a dietary intervention.

Effects of the exercise training on skeletal muscle oxygen consumption in heart failure patients with reduced ejection fraction

AimsSkeletal muscle dysfunction is a systemic consequence of heart failure (HF) that correlates with functional capacity. However, the impairment within the skeletal muscle is not well established. We investigated the effect of exercise training on peripheral muscular performance and oxygenation in HF patients. Methods and resultsHF patients with ejection fraction ≤40% were randomized 2:1 to exercise training or control for 12 weeks. Muscle tissue oxygen was measured noninvasively by near-infrared spectroscopy (NIRS) during rest and a symptom-limited cardiopulmonary exercise test (CPET) before and after intervention. Measurements included skeletal muscle oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, total hemoglobin concentration, VO2 peak, VE/VCO2 slope, and heart rate. Muscle sympathetic nerve activity by microneurography, and muscle blood flow by plethysmography were also assessed at rest pre and post 12 weeks. Twenty-four participants (47.5 ± 7.4 years, 58% men, 75% no ischemic) were allocated to exercise training (ET, n = 16) or control (CG, n = 8). At baseline, no differences between groups were found. Exercise improved VO2 peak, slope VE/VCO2, and heart rate. After the intervention, significant improvements at rest were seen in the ET group in muscle sympathetic nerve activity and muscle blood flow. Concomitantly, a significant decreased in Oxy-Hb (from 29.4 ± 20.4 to 15.7 ± 9.0 μmol, p = 0.01), Deoxi-Hb (from 16.3 ± 8.2 to 12.2 ± 6.0 μmol, p = 0.003) and HbT (from 45.7 ± 27.6 to 27.7 ± 13.4 μmol, p = 0.008) was detected at peak exercise after training. No changes were observed in the control group. ConclusionExercise training improves skeletal muscle function and functional capacity in HF patients with reduced ejection fraction. This improvement was associated with increased oxygenation of the peripheral muscles, increased muscle blood flow, and decreased sympathetic nerve activity.

MP36-07 ASSOCIATION BETWEEN LOW TESTOSTERONE AND ANEMIA: ANALYSIS OF THE NATIONAL HEALTH AND NUTRITION EXAMINATION SURVEY 8.6.1

You have accessJournal of UrologySexual Function/Dysfunction: Medical, Hormonal & Non-surgical Therapy II (MP36)1 Sep 2021MP36-07 ASSOCIATION BETWEEN LOW TESTOSTERONE AND ANEMIA: ANALYSIS OF THE NATIONAL HEALTH AND NUTRITION EXAMINATION SURVEY 8.6.1 Sirpi Nackeeran, Ruben Blachman-Braun, David Valancy, Manish Kuchakulla, and Ranjith Ramasamy Sirpi NackeeranSirpi Nackeeran More articles by this author , Ruben Blachman-BraunRuben Blachman-Braun More articles by this author , David ValancyDavid Valancy More articles by this author , Manish KuchakullaManish Kuchakulla More articles by this author , and Ranjith RamasamyRanjith Ramasamy More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002045.07AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Androgen effect on hematopoiesis has been long studied. Multiple clinical studies have shown an association between secondary polycythemia and testosterone replacement therapy (TRT) in hypogonadal men, however, the effect of endogenous serum testosterone on hemoglobin levels still needs to be elucidated. We analyzed data from the Third National Health And Nutrition Examination Study (NHANES III) to explore the association of total serum testosterone, low testosterone (≤300 ng/dL), hemoglobin concentration and prevalence of anemia in a nationally representative sample of men. METHODS: We collected de-identified, publicly available population data from the NHANES III database. Men between the age of 18 to 80 years of age were selected. We defined anemia as hemoglobin ≤13.5 ng/dL, and low serum testosterone as ≤300 ng/dL. Clinical and demographic characteristics such as race/ethnicity, smoking status, history of diabetes mellitus was recorded. We performed a univariable linear regression analysis between each independent variable and anemia, and multiple regression analysis considering hemoglobin predicting a negative linear relationship between anemia prevalence and serum testosterone. RESULTS: A total of 5888 men were analyzed. Those with anemia had a higher prevalence of low serum testosterone (32.3%) compared to those without anemia (24.1%) (p<0.001). After adjusting for the variables mentioned above, multiple linear regression showed that for each 10 ng/dL increase in serum testosterone is associated with an expected increase of 0.01 ng/dL of hemoglobin (p<0.001). Furthermore, having low testosterone was significantly associated with anemia (OR=1.44; 95% CI: 1.17-1.78; p=0.001). CONCLUSIONS: In a well-characterized American cohort, it was shown that men with low serum testosterone have a higher risk of anemia, and there is a positive association between serum testosterone and serum Hb. Further prospective studies need to be performed to confirm our findings. Source of Funding: © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e638-e638 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sirpi Nackeeran More articles by this author Ruben Blachman-Braun More articles by this author David Valancy More articles by this author Manish Kuchakulla More articles by this author Ranjith Ramasamy More articles by this author Expand All Advertisement Loading ...

FNIRS Monitoring of Infant Prefrontal Cortex During Crawling and an Executive Functioning Task

Functional near-infrared spectroscopy (fNIRS)is a brain-imaging technology used to reveal brain activity by measuring blood oxygenation. Using fNIRS we measured activity in the left prefrontal lobe of 8–14 month-old infants as they crawled or were pushed in a stroller and as they were given a passive attention task or an active executive function (EF) task. For each task, we measured peak total hemoglobin concentration and peak Oxy relative to baseline. Results revealed differences in peak Oxy levels for crawling vs. strolling and between the EF and passive cognitive tasks, with total hemoglobin greater for the EF task than the passive attention task. These results support the theoretical view that both active locomotion and EF engage the prefrontal cortex (PFC) during early development.

Haematological changes in Wistar rats experimentally infected with Trypanosoma congolense and Trypanosoma brucei brucei obtained from North-west Nigeria

This study determined haematological changes in Wistar rats experimentally infected with local strains of Trypanosoma congolense and Trypanosoma brucei brucei. Forty-five Wistar rats between 10 – 12 weeks old weighing between 210 – 240 g were used. The Wistar rats were randomly divided into four groups (A, B, C and D), with the infected groups (B, C and D) having 10 rats each, while the uninfected control group (A) had 15 rats. Group A rats were not infected and served as the control, group B were infected with Trypanosoma congolense, group C were infected with Trypanosoma brucei brucei and group D were co-infected with Trypanosoma congolense and Trypanosoma brucei brucei. Infection was achieved using 0.1mL of blood containing approximately 1 × 103 trypanosomes intraperitoneally into each Wistar rat in the infected groups. Clinical signs were observed. The changes in the blood cells were assayed in the groups post-infection. Duncan’s Least Square Deviation showed significantly (p&lt;0.05) higher parasitaemia in infected groups. However, group D showed a higher significant (p&lt;0.05) difference in parasitaemia when compared to groups B and C. The pattern of mean parasitaemia for the infected groups, revealed a positive correlation with days of post-infection (p&lt;0.05) before the decline. The packed cell volume, total red blood cell count and haemoglobin concentration were significantly (p&lt;0.05) lower in infected groups B, C and D. The total white blood cell count, platelet counts and differential leucocyte count were significantly (p&lt;0.05) lower in infected groups when compared to the uninfected group. These findings suggest that co-infection with Trypanosoma congolense and Trypanosoma brucei brucei obtained from Wurno and Ngaski in Sokoto and Kebbi States respectively produced a more damaging effect on haematological parameters.

Association between low testosterone and anaemia: Analysis of the National Health and Nutrition Examination Survey.

There is an androgen effect on haematopoiesis; however, the effect of low testosterone in anaemia has not been fully studied. In this study, we aim to explore the association of total serum testosterone, low testosterone (≤300ng/dl), haemoglobin concentration and prevalence of anaemia in a nationally representative sample of men. We analysed data from the NHANES III database, and men between the age of 18-80years of age were selected. We defined anaemia as haemoglobin ≤13.5ng/dl and low serum testosterone as ≤300ng/dl. After analysing 5,888 men, it was shown that those with anaemia had a higher prevalence of low serum testosterone (32.3%) compared to those without anaemia (24.1%) (p<.001), and in multivariable-adjusted analysis, it was shown that low testosterone was significantly associated with anaemia (OR=1.44; 95% CI: 1.17-1.78; p=.001). Our findings suggest that men with low serum testosterone have a higher risk of anaemia, and there is a positive association between serum testosterone and serum Hb. Further prospective studies need to be performed to confirm our findings.

Monitoring adaptation of skin tissue oxygenation during cycling ergometer exercise by frequency-domain diffuse optical spectroscopy.

In addition to supplying oxygen molecule O2 for metabolic functions during the adaptation to exercise, blood also plays a critical role in heat dissipation for core temperature stabilization. This study investigates the status of hemodynamic oxygenation in the forearm's skin tissue of three participants during a complete ergometer exercise from the resting to exercising, and to recovering conditions using a three-wavelength frequency-domain diffuse reflectance spectroscopy (FD DRS) alongside the monitoring of heartbeat rate and skin temperature. The FD DRS system was synchronized with radiofrequency (RF)-modulated input photon sources and the respective output to extract time-course absorption and scattering coefficients of the skin tissue, which, through the fitting of lambert's law of absorbance, can be used to determine the concentration of oxygenated/deoxygenated hemoglobin molecules, and consequentially, the oxygen saturation of skin tissue and total hemoglobin (THb) concentration. Expressly, a sudden jump in heartbeat rate at the beginning of the exercise, a temporal lag of the rising edge of skin temperature behind that of the THb concentration in the procession of step-wise incremental working intensity, and the uprising of THb in the exhaustion zone in responses to the physiological adaptation to exercise were identified. Finally, conclusive remarks were drawn that the FD DRS system is useful in extracting the hemodynamic properties of forearm skin which is often being neglected in previous exercise physiology studies by DRS-related techniques. The detailed variation of hemodynamic and optical scattering parameters of forearm skin elucidated in the studies can be applied for the analysis of athletes' physiological status, and may be a potential reference for the design of future wearable devices.

Changes of Apomorphine-Induced Vaginal Hemodynamics in an Ovariectomized Rat Model Using Near-Infrared Spectroscopic Probe

IntroductionFemale sexual arousal disorder (FSAD) can be caused by the change in vaginal structure due to the decline of estrogen and one of the main symptoms is vaginal dryness. FSAD is a prevalent problem afflicting women all over the world and thus the interest is growing on the matter, but related studies of monitoring FSAD using a non-invasive optical method barely have been carried out. AimThis study aims to investigate the longitudinal changes in female sexual arousal response induced by apomorphine (APO) administration in the ovariectomized rat using near-infrared spectroscopy (NIRS) probe. MethodsTo elicit sexual arousal, APO was administered subcutaneously to animals (n = 6) before and after ovariectomy, and the changes in oxyhemoglobin (OHb), deoxyhemoglobin (RHb), total hemoglobin (THb) concentration, and temperature on the vaginal wall after APO administration were monitored bi-weekly for 8 weeks. Furthermore, estradiol hormone, vaginal secretion, and body weight have been measured for comparison with the results from vaginal hemodynamics. ResultsAPO administration caused the increase of vaginal OHb and RHb concentration but a decrease in temperature. The amplitude of OHb, RHb, and THb increase induced by APO gradually decreased over 8 weeks after ovariectomy while the decrease in vaginal temperature became profound. The level of estradiol and vaginal secretions also decreased over 8 weeks after ovariectomy, but bodyweight showed an increasing trend. ConclusionsA comparison between the parameters measured from the NIRS probe and the others (estradiol level, amount of vaginal secretion, and body weight) proved that the NIRS has the potential as a monitoring tool to evaluate female sexual arousal response.Jeong H, Lee HS, Seong M, et al. Changes of Apomorphine-Induced Vaginal Hemodynamics in an Ovariectomized Rat Model Using Near-Infrared Spectroscopic Probe. J Sex Med 2021;18:1328–1336.

Diffuse optical tomography breast imaging measurements are modifiable with pre-surgical targeted and endocrine therapies among women with early stage breast cancer

Diffuse optical tomography breast imaging system (DOTBIS) non-invasively measures tissue concentration of hemoglobin, which is a potential biomarker of short-term response to neoadjuvant chemotherapy. We evaluated whether DOTBIS-derived measurements are modifiable with targeted therapies, including AKT inhibition and endocrine therapy. We conducted a proof of principle study in seven postmenopausal women with stage I-III breast cancer who were enrolled in pre-surgical studies of the AKT inhibitor MK-2206 (n = 4) or the aromatase inhibitors exemestane (n = 2) and letrozole (n = 1). We performed DOTBIS at baseline (before initiation of therapy) and post-therapy in the affected breast (tumor volume) and contralateral, unaffected breast, and measured tissue concentrations (in μM) of total hemoglobin (ctTHb), oxyhemoglobin (ctO2Hb), and deoxyhemoglobin (ctHHb), as well as water fraction (%). We found consistent decreases in DOTBIS-measured hemoglobin concentrations in tumor volume, with median percent changes for ctTHb, ctHHb, ctO2Hb, and water fraction for the entire cohort of -27.1% (interquartile range [IQR] 37.5%), -49.8% (IQR 29.3%), -33.5% (IQR 47.4%), and -3.6% (IQR 10.6%), respectively. In the contralateral breast, median percent changes for ctTHb, ctHHb, ctO2Hb, and water fraction were + 1.8% (IQR 26.7%), -8.6% (IQR 29.3%), + 6.2% (IQR 29.5%), and + 1.9% (IQR 30.7%), respectively. We demonstrated that DOTBIS-derived measurements are modifiable with pre-surgical AKT inhibition and endocrine therapy, supporting further investigation of DOTBIS as a potential imaging assessment of response to neoadjuvant targeted therapies in early stage breast cancer.

Rejuvenated RBCs Increase Oxygen Consumption in a Simulated Exchange Transfusion Model of Sickle Cell Disease Patients

Introduction: Exchange transfusion of red blood cells (RBCs) in patients with Sickle Cell Disease (SCD) may require 6 to 8 units to reduce sickle hemoglobin (Hb-S) to less than 30 percent of total hemoglobin (NIH No. 02-2117). Low oxygen affinity (high p50) in patients with SCD is manifested by impaired blood viscosities and reduced hemoglobin concentration. Well characterized RBC metabolic changes during liquid storage of donor RBC include an increase in the affinity of hemoglobin for oxygen (low p50) by depletion of 2,3-diphosphoglycerate (2,3-DPG). Transfusion of stored RBCs (Standard RBC) suggests inefficient and impaired O2 delivery to tissues compared to fresh circulating RBCs (Hasan 1994, Scott 2016) or after exchange transfusion in SCD (Uchida 1998). Extracorporeal manipulation of p50 through RBC rejuvenation increases the level of 2,3-DPG and increases the p50 of stored RBCs by right-shifting the Oxyhemoglobin Dissociation Curve (ODC) (Dennis 1979). Rejuvenation occurs by incubating RBCs at 37 °C for 60 minutes with a rejuvenation solution (Citra Labs). An exchange transfusion simulation model was developed to evaluate the changes in oxygen release capacity of rejuvenated RBCs and the potential impact on estimated oxygen consumption (VO2) compared to Standard RBCs.Methods: Oxyhemoglobin dissociation curves were generated from (5) RBC units (leukocyte-reduced), CPD/AS-1, on Day 0, after 21 days of storage (Standard RBC), and after rejuvenation on day 21 (REJ RBC) which were used to estimate p50 values of the donor/recipient mixtures after each exchange transfusion and to determine VO2 as previously described (Li 2016, Srinivasan 2017). An elevated p50 of 30.4 mm Hg, typical for SCD patients (Uchida 1998), was used to estimate the baseline VO2 (200 mL O2/min). VO2 was determined after each simulated RBC exchange with Standard or REJ RBCs assuming a constant blood volume of 5L, cardiac output of 5 L/min, total hemoglobin concentration of 10 g/dL. The model assumed an exchange rate of one apheresis unit of circulating RBCs to transfusion of one unit of Standard or REJ RBCs.Results: Donor RBC p50 was 26.9 ± 2.0 mm Hg on Day 0 and declined with storage to 17.6 ± 1.5 mm Hg at 21 days (p < 0.001, t-test). Rejuvenation restored p50 to 34.8 ± 2.7 mm Hg which was significantly higher than Day 0 (p < 0.001, t-test). The model predicted a reduction in Hb-S from 70 % to 22%, a decrease in p50 after the 8 unit exchange transfusion to 21.6 mm Hg with Standard RBC, but an increase in p50 to 33.3 mm Hg with REJ RBC (Figures 1a & 1b). Similarly, VO2 increased in the REJ RBC group but decreased sequentially with Standard RBC upon each additional exchange transfusion (Figure 1c). The model predicted a decrease in VO2 to 118 mL O2/min for the Standard RBC group and an increase to 233 mL O2/min with REJ RBC group after the exchange transfusion.Conclusions: The model predicted a baseline VO2 of 200 mL O2/min; however, in fresh whole blood from healthy volunteers with Hb-A, normal VO2 was estimated at 244 mL O2/min (Srinivasan 2017). This simulation suggested that performing an exchange transfusion with REJ RBCs could achieve 95% of normal oxygen consumption assuming a constant cardiac output even though the hemoglobin was maintained at 10 g/dL. While exchange transfusion has been a successful therapy to reduce the Hb-S percentage in chronically transfused SCD patients, improving tissue oxygen exchange may not yet be optimized as evidenced by post transfusion declines in p50 (Miller 1980, Uchida 1998). The model is limited because it does not account for improved rheological properties and blood viscosity following exchange transfusion, which was previously reported to improve exercise capacity even though p50 declined (Miller 1980). The model also did not account for any influence from irreversibly sickled cells. Transfusion practices to correct anemia and improve tissue oxygenation may be less effective than intended due to the diminished oxygen release capacity of standard stored RBC units. Transfusion strategies should consider whether the use of RBCs with increased p50 may be physiologically advantageous.Figure 1: Predicted ODC (a) before and after the simulated exchange transfusion with Standard or REJ RBCs and predicted Hb-A vs Hb-S ratios (b) and VO2 (c) after each unit of the exchange transfusion with Standard or rejuvenated RBCs. [Display omitted] DisclosuresKausch:Zimmer Biomet: Employment, Research Funding. Gray:Zimmer Biomet: Employment, Research Funding. Landrigan:Zimmer Biomet: Employment, Research Funding.