Use of biomedical photonics in gynecological surgery: a uterine transplantation model

Aim: Uterine transplantation (UTx) has been proposed as a treatment for permanent absolute uterine factor infertility. The study aims were to compare pulse oximetry and multispectral imaging (MSI), for intraoperative tracking of uterine oxygen saturation in animal UTx models (rabbit and sheep). Results/methodology: Imaging results confirmed the re-establishment of adequate perfusion in the transplanted organ after surgery. Comparison of oxygen saturation values between the pre-UTx donor and post-UTx recipient, and pre-UTx and post-UTx recipient reveals a statistically significant decrease in saturation levels post-UTx. Conclusion: The use of MSI is the first case in gynecology and has demonstrated promise of possible future human use. MSI technique has advantages over pulse oximetry – it provides spatial information in a real-time, noncontact manner

Use of biomedical photonics in gynecological surgery: a uterine transplantation model

Aim: Uterine transplantation (UTx) has been proposed as a treatment for permanent absolute uterine factor infertility. The study aims were to compare pulse oximetry and multispectral imaging (MSI), for intraoperative tracking of uterine oxygen saturation in animal UTx models (rabbit and sheep). Results/methodology: Imaging results confirmed the re-establishment of adequate perfusion in the transplanted organ after surgery. Comparison of oxygen saturation values between the pre-UTx donor and post-UTx recipient, and pre-UTx and post-UTx recipient reveals a statistically significant decrease in saturation levels post-UTx. Conclusion: The use of MSI is the first case in gynecology and has demonstrated promise of possible future human use. MSI technique has advantages over pulse oximetry - it provides spatial information in a real-time, noncontact manner

Sendaway capillary NT-proBNP in pulmonary hypertension

\ua9 Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. BACKGROUND: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a biomarker of cardiac ventricular wall stress that is incorporated into pulmonary hypertension (PH) risk stratification models. Sendaway sampling may enable patients to perform NT-proBNP tests remotely. This UK-wide study aimed to assess the agreement of sendaway NT-proBNP with standard venous NT-proBNP and to assess the effect of delayed processing. METHODS: Reference venous NT-proBNP was collected from PH patients. Samples for capillary and venous sendaway tests were collected contemporaneously, mailed to a reference laboratory and processed at 3 and 7 days using a Roche Cobas e411 device. Differences in paired measurements were analysed with Passing-Bablok regression, percentage difference plots and the % difference in risk strata. RESULTS: 113 patients were included in the study. 13% of day 3 capillary samples were insufficient. Day 3 capillary samples were not equivalent to reference samples (Passing Bablok analysis slope of 0.91 (95% CI 0.88 to 0.93) and intercept of 6.0 (95% CI 0.2 to 15.9)). The relative median difference was -7% and there were acceptable limits of agreement. Day 3 capillary NT-proBNP accurately risk stratified patients in 93.5% of cases. By comparison, day 3 venous results accurately risk stratified patients in 90.1% of cases and were equivalent by Passing-Bablok regression. Delayed sampling of sendaway tests led to an unacceptable level of agreement and systematically underestimated NT-proBNP. CONCLUSIONS: Sendaway NT-proBNP sampling may provide an objective measure of right ventricular strain for virtual PH clinics. Results must be interpreted with caution in cases of delayed sampling

Effect of parasympathetic stimulation on brain activity during appraisal of fearful expressions

Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets

Assessment of endothelial function by brachial artery flow mediated dilatation in microvascular disease

<p>Abstract</p> <p>Background</p> <p>Cardiac syndrome X is an important therapeutic and diagnostic challenge to physician. Study of Csx patients may help to understand the pathophysiology of coronary microcirculation and to gain an insight on the management of these group patients.</p> <p>Methods</p> <p>We measured the flow mediated dilation of the brachial artery both endothelium dependent and independent vasodilatation by high resolution ultrasound in 30 cardiac syndrome X patients and matched with 30 healthy control subjects.</p> <p>Results</p> <p>Significantly decreased flow mediated dilatation was observed in patients when compared to control (9.42 ± 7.20 vs 21.11 ± 9.16 p < 0.01) but no significant difference was observed between groups in response to nitroglycerin (25.39 ± 6.82 vs 28.87 ± 8.69). Receiver operator characteristic analysis showed that value of < 11.11 had sensitivity of 80%, specificity 86.67%, positive predictive value 76.66%, negative predictive value 83.33%. In total, 46% of subjects had endothelial dysfunction and of them, CSX subjects had higher prevalence (76% vs 16% p < 0.01) than control subjects. Higher mean values of body mass index, systolic blood pressure and diastolic blood pressure was observed in subjects with FMD < 11.11 than > 11.11(p < 0.01). In logistic regression analysis, FMD was significantly associated with systolic blood pressure (Odds ratio 1.122 95% CI 1.053-1.196 p < 0.01) and body mass index (Odds 1.248 95%CI 0.995-1.56 p < 0.05).</p> <p>Conclusions</p> <p>The study suggests impairment of endothelial function in cardiac syndrome X patients. Increased Systolic blood pressure and body mass index may increase the risk of impairment of endothelial function in this group of patients.</p

The 2dF Galaxy Redshift Survey: correlation functions, peculiar velocities and the matter density of the Universe

We present a detailed analysis of the two-point correlation function, ξ(σ, π), from the 2dF Galaxy Redshift Survey (2dFGRS). The large size of the catalogue, which contains ∼220 000 redshifts, allows us to make high-precision measurements of various properties of the galaxy clustering pattern. The effective redshift at which our estimates are made is zs≈ 0.15, and similarly the effective luminosity, Ls≈ 1.4L*. We estimate the redshift-space correlation function, ξ(s), from which we measure the redshift-space clustering length, s0= 6.82 ± 0.28 h−1 Mpc. We also estimate the projected correlation function, Ξ(σ), and the real-space correlation function, ξ(r), which can be fit by a power law (r/r0), with r0= 5.05 ± 0.26 h−1 Mpc, γr= 1.67 ± 0.03. For r≳ 20 h−1 Mpc, ξ drops below a power law as, for instance, is expected in the popular Λ cold dark matter model. The ratio of amplitudes of the real- and redshift-space correlation functions on scales of 8–30 h−1 Mpc gives an estimate of the redshift-space distortion parameter β. The quadrupole moment of ξ(σ, π) on scales 30–40 h−1 Mpc provides another estimate of β. We also estimate the distribution function of pairwise peculiar velocities, ƒ(v), including rigorously the significant effect due to the infall velocities, and we find that the distribution is well fit by an exponential form. The accuracy of our ξ(σ, π) measurement is sufficient to constrain a model, which simultaneously fits the shape and amplitude of ξ(r) and the two redshift-space distortion effects parametrized by β and velocity dispersion, a. We find β= 0.49 ± 0.09 and a= 506 ± 52 km s−1, although the best-fitting values are strongly correlated. We measure the variation of the peculiar velocity dispersion with projected separation, a(σ), and find that the shape is consistent with models and simulations. This is the first time that β and ƒ(v) have been estimated from a self-consistent model of galaxy velocities. Using the constraints on bias from recent estimates, and taking account of redshift evolution, we conclude that β (L=L*, z= 0) = 0.47 ± 0.08, and that the present-day matter density of the Universe, Ωm≈ 0.3, consistent with other 2dFGRS estimates and independent analyses

Effective-Range Expansion of the Neutron-Deuteron Scattering Studied by a Quark-Model Nonlocal Gaussian Potential

The S-wave effective range parameters of the neutron-deuteron (nd) scattering are derived in the Faddeev formalism, using a nonlocal Gaussian potential based on the quark-model baryon-baryon interaction fss2. The spin-doublet low-energy eigenphase shift is sufficiently attractive to reproduce predictions by the AV18 plus Urbana three-nucleon force, yielding the observed value of the doublet scattering length and the correct differential cross sections below the deuteron breakup threshold. This conclusion is consistent with the previous result for the triton binding energy, which is nearly reproduced by fss2 without reinforcing it with the three-nucleon force.Comment: 21 pages, 6 figures and 6 tables, submitted to Prog. Theor. Phy

Reduced P300 amplitude during retrieval on a spatial working memory task in a community sample of adolescents who report psychotic symptoms.

BACKGROUND: Deficits in working memory are widely reported in schizophrenia and are considered a trait marker for the disorder. Event-related potentials (ERPs) and imaging data suggest that these differences in working memory performance may be due to aberrant functioning in the prefrontal and parietal cortices. Research suggests that many of the same risk factors for schizophrenia are shared with individuals from the general population who report psychotic symptoms. METHODS: Forty-two participants (age range 11--13 years) were divided into those who reported psychotic symptoms (N = 17) and those who reported no psychotic symptoms, i.e. the control group (N = 25). Behavioural differences in accuracy and reaction time were explored between the groups as well as electrophysiological correlates of working memory using a Spatial Working Memory Task, which was a variant of the Sternberg paradigm. Specifically, differences in the P300 component were explored across load level (low load and high load), location (positive probe i.e. in the same location as shown in the study stimulus and negative probe i.e. in a different location to the study stimulus) and between groups for the overall P300 timeframe. The effect of load was also explored at early and late timeframes of the P300 component (250-430 ms and 430-750 ms respectively). RESULTS: No between-group differences in the behavioural data were observed. Reduced amplitude of the P300 component was observed in the psychotic symptoms group relative to the control group at posterior electrode sites. Amplitude of the P300 component was reduced at high load for the late P300 timeframe at electrode sites Pz and POz. CONCLUSIONS: These results identify neural correlates of neurocognitive dysfunction associated with population level psychotic symptoms and provide insights into ERP abnormalities associated with the extended psychosis phenotype

Effect of Food Residues on Norovirus Survival on Stainless Steel Surfaces

Background: In households and food processing plants, minute food residues left behind from improper cleaning may influence the survivability of human norovirus on surfaces. In this study, the survivability of norovirus on desiccated food residue-attached stainless steel coupons was investigated. Methodology/Principal Findings: Using murine norovirus-1 (MNV-1) as a surrogate of human norovirus, the survivability of norovirus was investigated on lettuce, cabbage, or ground pork-attached stainless steel coupons. A 6.2 log MPN/ml of MNV-1 infectivity was completely lost at day 30 in residue-free coupons, whereas only a 1.4 log MPN/ml reduction was observed in coupons with residues. Moreover, the disinfective effect of sodium hypochlorite was reduced when residues were present on the coupons. Conclusions/Significance: This study revealed that the food residues increased the survivability and the resistance to chemicals of norovirus, indicating the need of thorough cleaning in food processing plants and household settings