Age-related changes in hematological and biochemical profiles of Wistar rats.

BACKGROUND: Wistar rats are extensively used as the model for assessing toxicity and efficacy in preclinical research. Hematological and biochemical laboratory data are essential for evaluating specific variations in the physiological and functional profile of a laboratory animal. Establishing hematological and biochemical reference values for Wistar (han) rats at various age intervals was the goal of this work. Male and female Wistar rats (n = 660) of ages 6-8 weeks, 10-14 weeks and > 6 months were used in the experiment. Blood and serum were collected from these rats under fasting conditions. RESULTS: We observed that the majority of hematological and biochemical parameters were significantly influenced by sex and age. Hematological changes were significantly correlated to aging were increased red blood cells, hemoglobin, hematocrit, neutrophils, monocytes and eosinophils in both sexes, as well as decreased platelet, mean corpuscular volume, mean corpuscular hemoglobin and lymphocytes in both sexes. White blood cells of male rats were considerably higher than those of female rats in all age ranges. For biochemistry, increase in glucose, total protein and creatinine were seen in both sexes, along with increases in urea in females and alanine aminotransferase in males. Age was significantly associated with decreased alkaline phosphatase in both sexes. CONCLUSIONS: When using Wistar rats as a model, these reference values may be useful in evaluating the results.

Sustainable pathways for solar desalination using nanofluids: A critical review.

Water is a fundamental requirement for the survival of human beings. Although water is abundantly available across the globe, access to freshwater still remains a major concern. Most of the water available is saline or brackish, which is not fit for human consumption. Desalination is the optimum solution for production of potable water from saline water. A major shortcoming of conventional desalination technologies is their dependence on fossil fuel that results in environmental degradation, global warming, etc. Therefore, sustainable desalination technology has evolved as a need of hour. Among all renewable energy resources, solar energy is abundantly available and can be potentially harvested. Therefore, solar energy can be used to drive sustainable desalination technologies. A solar still converts saline water into freshwater in a single step using solar energy. But the major drawbacks of solar still are relatively lower efficiency and lower yield. Nanofluids are widely used to overcome these limitations due to their extraordinary and unique properties. This paper critically reviews the recent research performed on the application of nanofluids in solar desalination systems. Methods of nanofluid preparation, their types and properties are also discussed in detail. Application of nanofluids in solar desalination systems is discussed with special attention on performance enhancement of solar stills. Combinations of nanofluids with various other performance enhancement techniques are also considered. The effectiveness of nanofluids in solar stills is found to be dependent majorly on the nature and concentration of the nanofluid used.

Drying characteristics of thin layer of potato (Solanum tuberosum): experimental and computational studies.

Solar drying is a renewable energy-based technique which is widely used for food preservation purpose. In this study, various drying characteristics of the solar-dried Solanum tuberosum samples of different thicknesses have been investigated at variable climate condition of Lucknow. A mathematical model has also been developed to validate experimental results to predict the drying rate, free moisture content, and other parameters. Pre-treatment of the food samples was also done before the experimental runs on the fabricated solar dryer. Global radiation has also been monitored during the study to correlate the heat transfer rate in inner and outer sides of the solar drying chamber. SEM analysis has also been done to analyze the surface morphology of solar-dried samples. All solar dried food samples have uniformly heated. There was no hot-spot condition present on the surface of the samples. The drying efficiency and payback period of the fabricated solar dryer have also been calculated as 22.9% and 1.42 years, respectively. Model data have been found in good agreement with the experimental data within a 5% error. This modified model can be used for different agro-based food materials such as carrot, kiwifruit, and yam.

Experimental investigation of different-shaped microwave-heated potatoes: thermal and quality characteristics analysis for food preservation.

Food materials are consumed for nutritional purposes in the form of fruits, vegetables, plants, and meat. These contain proteins, carbohydrates, and other useful nutritional compounds and these processed foods are a rich source of nutrition. The demand and supply of hygienic food for a particular population is possible only by food preservation. It can be done by various methods such as drying, freezing, chilling, chemical preservation, and pasteurization. Drying is a method of food preservation and it can be done by solar drying, microwave heating, vacuum drying, and some other methods. Microwave heating is a fast-drying method. It utilizes electrical energy to generate heat energy. The domestic microwave oven is not harmful but a commercial-level oven may be little bit harmful, when operated on high frequency. Potato is used as a sample material with different shapes such as slab, cylindrical, and spherical. The microwave oven has been operated at four different microwave powers such as 100 W, 300 W, 600 W, and 800 W. Slab-shaped (30 °C), cylindrical-shaped (31.5 °C), and spherical-shaped (30.5 °C) food materials achieved maximum temperatures of 83.9 °C, 110.6 °C, and 146.1 °C respectively. The temperature variations and drying characteristics of the food samples have been monitored. An oven has achieved maximum drying efficiency of 25.65% with a slab-shaped sample. For the detection of the cracks and chemical compositions in the food samples, SEM with EDS analysis has been performed. Economic analysis of microwave oven has also been done and payback period has been found as 3.27 years.

Changes in Mode of Oxygen Delivery and Physiological Parameters with Physiotherapy in COVID-19 Patients: A Retrospective Study.

Background: Coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2, clinically presenting with common symptoms of fever, dry cough, and breathlessness within 14 days of exposure. Its severity ranges from mild to severe, latter manifesting into severe acute respiratory syndrome. As a part of multidisciplinary team, physiotherapy along with medical management was administered to patients with COVID-19 in an acute care setup. This retrospective study aims to explore various patient characteristics and will aid in identifying the impairments associated with the disease, giving a direction to the physiotherapy community in planning future management strategy to improve quality of life. Patients and methods: The present study is a unicentric study wherein prospective analysis of retrospective data of patients referred for physiotherapy from May 13 to July 31, 2020, was performed. (i) Characteristics of patients, (ii) associated comorbidities, (iii) hospital course since the time of admission to discharge, (iv) mode of oxygen delivery, (v) pre- and post-physiotherapy treatment values of oxygen saturation and heart rate, and (vi) physiotherapy treatment were recorded. The archived data were analyzed using the commercially available SPSS software version 24. Wilcoxon's matched pair test was used to compare pre- and post-treatment oxygen saturation and heart rate, and McNemar's test was used to compare mode of oxygen delivery and pre- and post-physiotherapy treatment. Results: Descriptive analysis of data showed a better outcome in terms of grade of dyspnea and rate of discharge on day 14 of physiotherapy treatment. Hence, a comparative analysis of day 1 and day 14 was performed for mode of oxygen delivery, oxygen saturation, and heart rate. A statistically significant improvement was observed in the heart rate (p = 0.001) and oxygen delivery (p = 0.000). However, no significant difference in the level of oxygen saturation was found (p = 0.6433). Conclusion: Physiotherapy treatment in conjunction with medical treatment can be effectively administered in patients with COVID-19 in acute care setup taking into consideration the health status and the hemodynamic stability of the patients. It emphasizes the role of physiotherapy in the alleviation of symptoms, facilitating early weaning and recovery enabling early discharge from the hospital. How to cite this article: Verma CV, Arora RD, Mistry HM, Kubal SV, Kolwankar NS, Patil PC, et al. Changes in Mode of Oxygen Delivery and Physiological Parameters with Physiotherapy in COVID-19 Patients: A Retrospective Study. Indian J Crit Care Med 2021;25(3):317-321.

Imaging Findings in Non-Neoplastic Sinonasal Disease: Review of Imaging Features With Endoscopic Correlates.

Non-neoplastic sinonasal disease is common and imaging often plays an important role in establishing the proper diagnosis, guiding clinical management, and evaluating for complications. Both computed tomography and magnetic resonance imaging are commonly employed in the imaging evaluation and it is important to understand the imaging characteristics of the unique types of pathology affecting the sinonasal cavities. This article reviews a variety of infectious, inflammatory, and other non-neoplastic sinonasal pathologies, highlighting imaging features that aid in their differentiation.

The reliability of identifying the Omega sign using axial T2-weighted magnetic resonance imaging.

Preoperative identification of the eloquent brain is important for neurosurgical planning. One common method of finding the motor cortex is by localizing "the Omega sign." No studies have tested the reliability of imaging to identify the Omega sign. We identified 40 recent and consecutive patients who had undergone preoperative functional magnetic resonance imaging for identification of the hand motor area prior to tumor resection. We recruited 11 neurosurgical residents of various levels of training and one board-certified neurosurgeon to identify the hand motor cortex Omega. Testees were given axial images of T2-weighted MRI and placed marks where they expected to find the Omega. Two board-certified radiologists graded and quantified the localization attempts. Inter-rater reliability was assessed using the kappa statistic, and Rao-Scott chi-square tests were used to examine the relationship between clinical factors and testees' experience with correct identification of the Omega sign. The overall correct identification rate was 69.9% (95% CI = 63.4-75.7), ranging from 36.6% to 92.7% among all raters for the tumor side and from 46.2% to 97.4% for the non-tumor side. Anatomic distortion greatly affected correct identification ( p < 0.005). Senior residents had a significantly higher rate of identification of the Omega than junior residents ( p < 0.001). Overall, inter-rater reliability for the Omega sign is poor, with a Fleiss kappa of 0.23. We concluded that correct identification of the Omega sign is affected by tumor distortion and experience but overall is not reliable. This underscores the limitations of anatomic landmarks and the importance of utilizing multiple scanning planes and preoperative fMRI for appropriate localization.

Cord Topographical Anatomy and its Role in Evaluating Intramedullary Lesions.

Intramedullary spinal lesions present a wide differential diagnosis including infectious, inflammatory, traumatic, ischemic, benign, or malignant neoplastic etiologies. Using knowledge of anatomy and physiology within the spinal cord, many similar appearing entities can be parsed into a prioritized differential. The purpose of this article is to review anatomy and pathophysiology of the spinal cord, with subsequent discussion of how this knowledge can be used to differentiate several similar appearing intramedullary pathologic processes. Discussion includes the pathophysiology, imaging findings, and clinical pearls of several intramural lesions including infarct, demyelinating lesions, traumatic injury, neoplasm, vascular malformation, and metabolic processes such as subacute combined degeneration.

Reformatted images of the thoracic and lumbar spine following CT of chest, abdomen, and pelvis in the setting of blunt trauma: are they necessary?

Injuries involving the thoracic and lumbar (TL) spine in the setting of blunt trauma are not uncommon. At our institution, CT of the chest, abdomen, and pelvis (CT CAP) with dedicated reformatted images of the thoracolumbar spine (CT TL) is part of the standard work-up of patients following significant blunt trauma. The purpose of this study was to compare the detection rate of TL spine fractures on routine trauma CT CAP with reformatted CT TL spine images and determine whether these reformatted images detect additional fractures and if these altered patient management. The imaging records of 1000 consecutive patients who received blunt trauma protocol CT CAP with CT TL spine reformats were reviewed to determine identification of TL spine fracture in each report. Fracture type and location were documented. Of the 896 patients, 66 (7.4 %) had fractures of the TL spine identified on either CT CAP or CT TL spine. Of these 66 patients, 40 (60.6 %) had fractures identified on both CT CAP and CT TL spine and 24 (36.4 %) had fractures identified on CT TL spine images alone. Fourteen patients required treatment with surgery or bracing, 4 (28.6 %) of which had fractures identified on reformatted TL spine imaging only. In conclusion, a significant number of fractures are detected on TL spine reformats that are not identified on CT CAP alone, altering patient management in a few cases and suggesting that dedicated TL spine reformats should be a standard part of the work-up of blunt trauma patients.

Perfusion and Diffusion Abnormalities of Multiple Sclerosis Lesions and Relevance of Classified Lesions to Disease Status.

OBJECTIVE: Hemodynamic abnormality and disruption of white matter (WM) integrity are significant components in the pathophysiology of multiple sclerosis (MS) lesions. However, the roles of stratified lesions with distinct degrees of hemodynamic and structural injury in disease states remain to be explored. We tested the hypothesis that hemodynamic and structural impairment, as assessed by cerebral blood volume (CBV) and fractional anisotropy (FA), respectively, characterizes the extent of tissue injury, and the load of lesion with substantial tissue destruction would reflect the disease status and therefore, would be related to clinical disability. METHODS: Seven relapsing-remitting MS patients and seven healthy controls underwent perfusion, diffusion and conventional MRI scans. Based on T2-FLAIR and T1-weighted image, WM plaques were classified. After image coregistration, values of CBV and FA were estimated in three distinct lesion types (active, T1-hypointense and T1-isointense lesion) and compared with those obtained in WM from controls. A total of 1135 lesions were evaluated. Brain volumetric measurement and correlative analysis between brain atrophy, lesion volume and clinical disability were also performed. RESULTS: Compared with normal WM, significantly reduced CBV and FA were present in the T1-hypointense lesion, while insignificant changes in both parameters were exhibited in the T1-isointense lesion. However, increased CBV but significantly decreased FA was detected in the active lesion. A close spatial relationship between active and T1-hypointense lesion was observed. Lesion load represented by T1-hypointense plus active lesion volume significantly correlated with brain atrophy, which, in turn, significantly correlated with the severity of clinical disability. CONCLUSION: A distinct combination of CBV and FA characterizes the status of a specific lesion type. A severe structural impairment does not solely occur in the T1-hypointense lesion, but is also associated with the active lesion. The burden of the lesion with extensive structural damage provides an image index, indicative of disease status.

Effect of radiation dose and iterative reconstruction on lung lesion conspicuity at MDCT: does one size fit all?

OBJECTIVE: To evaluate the effect of different acquisition parameters and reconstruction algorithms in lung lesions conspicuity in chest MDCT. METHODS: An anthropomorphic chest phantom containing 6 models of lung disease (ground glass opacity, bronchial polyp, solid nodule, ground glass nodule, emphysema and tree-in-bud) was scanned using 80, 100 and 120 kVp, with fixed mAs ranging from 10 to 110. The scans were reconstructed using filtered back projection (FBP) and iterative reconstruction (IR) algorithms. Three blinded thoracic radiologists reviewed the images and scored lesions conspicuity and overall image quality. Image noise and radiation dose parameters were recorded. RESULTS: All acquisitions with 120 kVp received a score of 3 (acceptable) or higher for overall image quality. There was no significant difference between IR and FBP within each setting for overall image quality (p>0.05), even though image noise was significantly lower using IR (p<0.0001). When comparing specific lower radiation acquisition parameters 100 kVp/10 mAs [Effective Dose (ED): 0.238 mSv] vs 120 kVp/10 mAs (ED: 0.406 mSv) vs 80 kVp/40 mAs (ED: 0.434 mSv), we observed significant difference in lesions conspicuity (p<0.02), as well as significant difference in overall image quality, independent of the reconstruction algorithm (p<0.02), with higher scores on the 120 kV/10 mAs setting. Tree-in-bud pattern, ground glass nodule and ground glass opacity required lower radiation doses to get a diagnostic score using IR when compared to FBP. CONCLUSION: Designing protocols for specific lung pathologies using lower dose acquisition parameters is feasible, and by applying iterative reconstruction, radiologists may have better diagnostic confidence to evaluate some lesions in very low dose settings, preserving acceptable image quality.

Proof of concept study: relating infarct location to stroke disability in the NINDS rt-PA trial.

BACKGROUND: The summed Alberta Stroke Program Early CT Score (ASPECTS) for noncontrast head CT scan represents the extent of early brain ischemia and has been shown to be useful for predicting stroke outcome. The ASPECTS template contains information on anatomical location which so far has not been used in analysis. This may not have been done because adjacent brain regions have related functions and share vascular territory. The task of relating neurological deficit to infarct localization requires brain imaging analysis tools which deal with this issue of relatedness or collinearity. We have previously used partial least squares with penalized logistic regression (PLR) to handle this problem of collinearity. A disadvantage of this method is that it cannot be performed at the bedside and requires processing and analysis in the imaging laboratory. PLR is a simpler analytic tool compared to partial least squares with PLR for dealing with this issue of relatedness (collinearity). It provides results in terms of ß coefficients related to specific infarct locations in a manner that is intuitively understood by clinicians. In this exploratory analysis, we hypothesized that infarct location as represented by the individual ASPECTS region may be independently related to disability. METHODS: ASPECTS from CT scans of patients in the National Institute of Neurological Disorders and Stroke (NINDS) recombinant tissue plasminogen activator (rt-PA) Study were obtained. Due to the collinearity between the ASPECTS regions, we used PLR to determine the independent associations of exposures (rt-PA), demographic variables (age and sex), and imaging (ASPECTS location) with poor outcome as defined by a modified Rankin Scale score of >2. RESULTS: In 607/624 subjects with ASPECTS readings, variables significantly associated with poor outcome included: interactions between ASPECTS M6 region (primary motor cortex/parietal lobe) and age (p = 0.004), lentiform nucleus and age (p = 0.007), and blood sugar level and age (p = 0.01). The model suggested that older age or involvement of either M6 or lentiform nucleus slightly increased the odds of disability. However, the predominant effect was driven by rt-PA which reduced the odds of poor disability (OR 0.597, 95% CI 0.425-0.838, p = 0.003). This may potentially explain why certain patients have smaller gains from rt-PA treatments. CONCLUSION: At an older age, specific infarct locations may be associated with a poorer outcome in this exploratory re-analysis of the NINDS rt-PA Study.

Preoperative localization of parathyroid adenomas using 4-dimensional computed tomography: a pictorial essay.

Accurate preoperative localization is the key to successful parathyroid surgery in the era of minimally invasive parathyroid surgery. This article presents and discusses the embryologic basis of parathyroid gland and ectopic location and different imaging modalities helpful in diagnosing and localizing parathyroid adenomas and/or hyperplasia. We also aim to review the current surgical concepts in treatment of parathyroid adenomas and/or hyperplasia, the utility of 4-dimensional computed tomography for accurate preoperative localization of hyperfunctioning parathyroid glands, imaging classification of adenomas and/or hyperplasia, and, finally, present some of the limitations of 4-dimensional computed tomography.

Three-dimensional volumetric measurements and analysis of the maxillary sinus.

BACKGROUND: Multiple chronic rhinosinusitis (CRS) staging systems have been developed in an attempt to correlate symptoms with radiological imaging results. Currently, no perfect system exists. We sought to analyze the maxillary sinus (MS) using three-dimensional volumetric measurements and advanced high-resolution CT imaging. METHODS: We reviewed MS CT scans from 50 control subjects and 50 subjects with documented CRS involving at least one MS. The following measurements were recorded: (1) volume of MS free air, (2) MS mucosal thickening, and (3) MS lateral wall bony thickness. Average Hounsfield unit (HU) values for mucosal thickening among CRS subjects were also recorded. Values are expressed as mean ± SD and median. Values from the CRS patients were compared with healthy controls using Student's t-tests. RESULTS: Among controls (n = 50), volumes (mL) of right and left MS were 24.1 ± 9.7 and 24.7 ± 9.0, respectively. Among CRS patients (n = 50), the portion of mucosal disease to total sinus volume was 51.8% (right) and 50.7% (left). Mean bony thickness (mm) in controls was 0.98 ± 0.2 (right) and 1.0 ± 0.3 (left). CRS patients had significantly greater bony thickness 1.9 ± 0.8 (right) and 2.0 ± 0.9 (left; p = 0.0001). HU for diseased MS were 30.1 ± 18.7 (right) and 35.7 ± 22.1 (left). CONCLUSION: Three-dimensional volumetric analysis combined with HU calculations and bony thickness measurements represents a new and unique way to evaluate CT scans in patients with CRS. Additional studies correlating symptoms with imaging findings as well as analysis of all paranasal sinuses is the next step toward a novel staging system.

Dataset of magnetic resonance images of nonepileptic subjects and temporal lobe epilepsy patients for validation of hippocampal segmentation techniques.

The hippocampus has become the focus of research in several neurodegenerative disorders. Automatic segmentation of this structure from magnetic resonance (MR) imaging scans of the brain facilitates this work. Segmentation techniques must be evaluated using a dataset of MR images with accurate hippocampal outlines generated manually. Manual segmentation is not a trivial task. Lack of a unique segmentation protocol and poor image quality are only two factors that have confounded the consistency required for comparative study. We have developed a publicly available dataset of T1-weighted (T1W) MR images of epileptic and nonepileptic subjects along with their hippocampal outlines to provide a means of evaluation of segmentation techniques. This dataset contains 50 T1W MR images, 40 epileptic and ten nonepileptic. All images were manually segmented by a widely used protocol. Twenty five images were selected for training and were provided with hippocampal labels. Twenty five other images were provided without labels for testing algorithms. The users are allowed to evaluate their generated labels for the test images using 11 segmentation similarity metrics. Using this dataset, we evaluated two segmentation algorithms, Brain Parser and Classifier Fusion and Labeling (CFL), trained by the training set. For Brain Parser, an average Dice coefficient of 0.64 was obtained with the testing set. For CFL, this value was 0.75. Such findings indicate a need for further improvement of segmentation algorithms in order to enhance reliability.