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Κυριακή 3 Ιουλίου 2022

How Peripheral Vestibular Damage Affects Velocity Storage: a Causative Explanation

alexandrossfakianakis shared this article with you from Inoreader
AbstractVelocity storage is a centrally-mediated mechanism that processes peripheral vestibular inputs. One prominent aspect of velocity storage is its effect on dynamic responses to yaw rotation. Specifically, when normal human subjects are accelerated to constant angular yaw velocity, horizontal eye movements and perceived angular velocity decay exponentially with a time constant circa 15 –30 s, even though the input from the vestibular periphery decays much faster (~ 6 s). Peripheral vestibular damage causes a time constant reduction, which is useful for clinical diagnoses, but a mechanistic explanation for the relationship between vestibular damage and changes in these behavi oral dynamics is lacking. It has been hypothesized that Bayesian optimization determines ideal velocity s...
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Exploring the impact of metabolic imaging in head and neck cancer treatment

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Background

Target volume delineation is performed with anatomical imaging for head and neck cancer. Molecular imaging allows the recognition of specific tumor regions. Its inclusion in the pathway could lead to changes in delineation and resultant treatment plans.

Methods

PRISMA methodology was adhered to when selecting the articles for analysis and only full articles were quality assessed.

Results

Seventeen articles were included. Gross tumor volume (GTV) primary, GTV nodal, and other target volumes were evaluated. Positron emission tomography/computerized tomography (PET/CT) produced smaller primary GTVs, although not with diffusion-weighted imaging-magnetic resonance imaging (DWI-MRI) or PET/MRI. The impact of these image modalities on GTV nodal did not display any consistency. Additionally, there was considerable heterogeneity in metrics comparing delineations. Four studies included appraised the dosimetric impact of the changes in target volume delineation.

Conclusion

Quantifying the impact of molecular imaging is difficult, due to heterogeneity in reporting metrics in molecular imaging modalities and a paucity of detail regarding delineation method and guideline adherence.
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Does three-dimensional intraglandular location predict malignancy in parotid tumors?

alexandrossfakianakis shared this article with you from Inoreader
Tumors arising within the parotid encompass a heterogeneous mix of benign and malignant neoplasms and other tissue growths. The purpose of this study was to determine the association between the location of intraparotid masses and the risk of malignancy. A retrospective cohort study was performed of patients diagnosed with parotid tumors following open tumor excision. The primary predictor variable was the location of the epicenter of the tumor in three-dimensional space, as determined from preoperative imaging. (Source: International Journal of Oral and Maxillofacial Surgery)
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Recovery from the damage of cranial radiation modulated by memantine, an NMDA receptor antagonist combined with hyperbaric oxygen therapy

alexandrossfakianakis shared this article with you from Inoreader
Abstract
Background
Radiotherapy is an important treatment option for central nervous system malignancies. However, cranial radiation induces hippocampal dysfunction and white matter injury; this leads to cognitive dysfunction, and results in a reduced quality of life in patients. Excitatory glutamate signaling through N-methyl-D-aspartate receptors (NMDARs) plays a central role both in hippocampal neurogenesis and in the myelination of oligodendrocytes in the cerebrum.
Methods
We will provide the method for quantifying neurogenesis in human subjects in live brain during the cancer therapy. Neuroimaging using behavioral task we originally create, to examine human hippocampal memory pathway in patients with brain disorders.
Results
Treatment with memantine, a non-competitive NMDAR antagonist, reversed impairment in hippocampal pattern separation networks as detected by functional magnetic resonance imaging. Hyperbaric preconditi oning of the patients just before radiotherapy with memantine most reversed white matter injury as detected by whole brain analysis with Tract-Based Spatial Statics. Neuromodulation combined with the administration of hyperbaric oxygen therapy and memantine during radiotherapy facilitated the restoration of hippocampal function and white matter integrity, and improved higher cognitive function in patients receiving cranial radiation.
Conclusions
The method for therapy and diagnosis of hippocampal function we developed can be applicable to the patients received cranial radiation to restore the cognitive decline. The monitoring can be followed during the therapy that production of new neurons by which ability of pattern separation is increased, then recovery of pattern completion, followed by new score elevation.
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Risk factors for high level cytomegalovirus viremia in liver transplant recipients and associated outcomes

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Purpose

To evaluate epidemiology, risk-factors and outcomes of high-level cytomegalovirus (CMV) viremia in liver transplant recipients.

Methods

Adult patients receiving a liver transplant between 1/1/2017-9/30/2020 were evaluated. Viral loads at UW Health Clinical Laboratories were required to allow for numerical comparison. Primary objective was incidence and outcomes of high-level (HL) CMV viremia (viral-load >100,000 IU/mL). Secondary objective was to elucidate risk factors to allow targeted interventions.

Results

209 patients met inclusion criteria; 175 kept their graft for at least 240 days. Of these 9 patients developed HL CMV, 28 developed low-level (LL CMV, viral-load 250–100,000 IU/mL) and 138 did not develop CMV viremia. When comparing these 3 groups via classic statistical methods time from transplant to viremia was similar (HL 158 ± 77 days, LL 150 ± 76 days). Clinical factors were also similar with the exception of donor seropositivity (HL 87.5%, LL 70.4%, No CMV 49.6%, p = 0.025). HL CMV was significantly associated with graft loss (p < 0.0001) on Kaplan-Meier analysis; graft loss in the LL CMV group did not differ from the No CMV group (p = 0.96)

To allow valid assessment of risk factors in the total study population (n = 209) models of time-varying covariates were used and Cox proportional hazards ratios were calculated. In this analysis HL CMV was associated with a significantly increased risk of graft loss (HR 5.6, p = 0.0016). When investigating risk factors associated with HL CMV, donor seropositivity significantly increased risk (HR 8.85, 95% CI 1.13–71.43, p = 0.038). Pre-transplant total bilirubin (HR 1.04, 95% CI 0.998–1.07, p = 0.06) trended towards significance. Recipient seronegativity, liver disease, clinical and allocation MELD, transplant surgery duration, age, sex, induction immunosuppression, and maintenance immunosuppression were not significantly associated with development of HL CMV.

Conclusion

HL CMV after liver transplant is uncommon but is associated with a significantly increased risk of graft loss that is not present in those patients who develop LL CMV or do not develop CMV viremia. Given these negative graft effects, CMV stewardship interventions targeting recipients of CMV seropositive allografts are warranted. Future larger scale studies evaluating the potential role of other factors in risk stratification are needed.

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