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1.
Clin Radiol ; 79(3): e393-e400, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38182477

ABSTRACT

AIM: To compare the performance of two non-contrast magnetic resonance angiography (MRA) sequences, silent MRA and time of flight (TOF) MRA, in the evaluation of intracranial dural arteriovenous fistula (DAVF). MATERIALS AND METHODS: Forty consecutive patients with DAVF were enrolled and evaluated prospectively using silent MRA, TOF MRA, and digital subtraction angiography (DSA). The location, Cognard classification, arterial feeders, and venous drainage were evaluated. The therapeutic strategy and possible route were predicted on both silent and TOF MRA and these were compared with DSA during subsequent endovascular treatment. RESULTS: Sensitivity and accuracy of silent and TOF MRA for localisation (96.4% versus 96% and 96% versus 95%, respectively) and classification (96% versus 94% and 96% versus 93.5%, respectively) were high. Silent MRA showed higher sensitivity than TOF MRA for arterial feeders and draining veins (87% versus 79% and 81.6% versus 67%). This improved to a sensitivity of 96.4% and 89% when prominent feeders were considered. The sensitivity and accuracy were 92.6% and 85.8% for immediate draining veins. Both silent and TOF MRA were accurate for therapeutic planning (96% versus 85%), although silent MRA was more accurate. CONCLUSION: Silent MRA can more reliably evaluate the various angioarchtectural components of DAVF compared to TOF MRA.


Subject(s)
Central Nervous System Vascular Malformations , Magnetic Resonance Angiography , Humans , Central Nervous System Vascular Malformations/diagnostic imaging , Angiography, Digital Subtraction , Veins , Magnetic Resonance Spectroscopy
2.
Phys Chem Chem Phys ; 24(42): 26200-26210, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36278810

ABSTRACT

Rapid crystallization of amorphous solid water (ASW) is often associated with crystallization that initiates at random nucleation sites in the bulk and expands in all directions. In this work, by preparing sandwich films of acetonitrile (ACN) and ASW in the form of ACN@ASW and ASW@ACN in an ultrahigh vacuum (UHV), we demonstrate a new method for rapid crystallization of ASW via ACN diffusion-desorption induced porosity in the ASW matrix even in the window of 128-134 K, well below the normal crystallization temperature of 155 K. By placing an HDO (5% D2O in H2O) probe layer in ASW, we found that when ACN diffuses and desorbs through ASW, it induces ASW crystallization where the crystal grows both from the top and from the bottom simultaneously into the bulk. Crystallization kinetics and activation energy (Ea) for the formation of crystalline ice (CI) were evaluated using the Avrami equation and were compared with the previous reports. The evaluated Ea was ∼53 kJ mol-1, close to the Ea of crystal growth (47-56 kJ mol-1) and it suggested the absence of a nucleation process and supported rapid crystallization. Such occurrence of CI due to diffusion of ACN suggests a possible mechanism for the former's existence in many astrophysical environments.

3.
J Invertebr Pathol ; 183: 107624, 2021 07.
Article in English | MEDLINE | ID: mdl-34077765

ABSTRACT

Hepatopancreatic microsporidiosis (HPM) is an infectious shrimp disease caused by the microsporidian Enterocytozoon hepatopenaei (EHP). In recent years, the widespread occurrence of EHP poses a significant challenge to the shrimp aquaculture industry. Early, rapid and accurate diagnosis of EHP infection is very much essential for the control of HPM crop-related losses. Loop-mediated isothermal amplification (LAMP) is a robust, sensitive, cost-effective disease diagnostic technique. Here, we demonstrate an improved, simple, closed-tube, colorimetric EHP LAMP diagnostic assay. LAMP assay was illustrated with the specific EHP spore wall protein (SWP) gene primers. Naked eye visual detection of LAMP amplicons was achieved using Hydroxy naphthol blue (HNB) or Phenol red dye without opening the tubes. This LAMP assay is efficient in detecting the EHP pathogen in all clinical samples include shrimp hepatopancreas, FTA card samples, feces, pond water, and soil. Also, the elution of EHP DNA from FTA cards was demonstrated within 17 min using a simple dry bath. In clinical evaluation, the visual LAMP assay established 100% diagnostic sensitivity and 100% diagnostic specificity. The visual LAMP assay is rapid, can detect the EHP pathogen within 40 min using a simple dry bath, and does not require any expensive instruments and technical proficiency. In conclusion, this visual LAMP protocol is a user-friendly, specific assay that can be conceivably operated at the farm-site/ resource-limited settings by the farmer himself with simple equipment.


Subject(s)
Antigens, Fungal/analysis , Enterocytozoon/isolation & purification , Fungal Proteins/analysis , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Enterocytozoon/genetics
4.
Clin Radiol ; 76(9): 712.e1-712.e8, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34144807

ABSTRACT

AIM: To evaluate the utility of silent magnetic resonance angiography (MRA) in the diagnosis, characterisation, and therapeutic planning of intracranial dural arteriovenous fistula (DAVF). MATERIALS AND METHODS: Twenty consecutive patients with DAVF were enrolled prospectively and were evaluated using silent MRA and digital subtraction angiography (DSA) as a part of routine work-up. The diagnosis and location of fistula, Borden and Cognard classification, entire arterial feeders, and venous drainage were analysed. A therapeutic strategy was formulated, and the accessible route and vessel were predicted, which was confirmed on endovascular treatment. RESULTS: Silent MRA was 100% sensitive and accurate for location and classification of fistulas. Silent MRA showed a sensitivity of 82% and 76.5% for entire arterial feeders and draining veins, which improved to a sensitivity of 90% and 94% when prominent feeders and immediate venous drainage was considered. Among the missed veins, thrombosed sinus, slow sinus flow, small calibre, reduced image quality were the causes. The therapeutic decision matched with DSA in all cases and silent MRA accurately identified the potential accessible feeder in 94% cases. CONCLUSION: Silent MRA is a promising MR technique that can provide both diagnostic and therapeutic information similar to that obtained from DSA.


Subject(s)
Central Nervous System Vascular Malformations/diagnostic imaging , Magnetic Resonance Angiography/methods , Adult , Aged , Angiography, Digital Subtraction/methods , Brain/diagnostic imaging , Female , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity , Young Adult
5.
Chem Commun (Camb) ; 56(100): 15623-15626, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33245313

ABSTRACT

We present the first example of acetylide protected silver clusters by a reaction between Ag17+ and acetylene, conducted around atmospheric pressure. The products were obtained after dehydrogenation of acetylene in the gas phase. The observed reaction mechanism may be helpful to design new catalysts useful in organometallic chemistry.

6.
Phys Chem Chem Phys ; 22(16): 8491-8498, 2020 Apr 28.
Article in English | MEDLINE | ID: mdl-32292940

ABSTRACT

Catalytic conversion of CO to CO2 has been investigated in ultrahigh vacuum (UHV) under cryogenic conditions (10 K). This cryogenic oxidation is assisted by iron upon its co-deposition with CO, on a substrate. The study shows that the interaction of Fe and CO results in a Fe-CO complex that reacts in the presence of excess CO at cryogenic conditions leading to CO2. Here, the presence of CO on the surface is a prerequisite for the reaction to occur. Different control experiments confirm that the reaction takes place in the condensed phase and not in the gas phase. Surface sensitive reflection absorption infrared spectroscopy (RAIRS), temperature programmed desorption (TPD), and Cs+ based low energy ion scattering are utilized for this study. The iron assisted formation of CO2 may be proposed as another pathway relevant in interstellar ices, containing CO. This direct oxidation process, which occurs at extremely low temperatures and pressures, in the presence of a reactive metal species like iron (the most abundant metal in the interstellar medium) may have astrochemical importance. It does not require any external energy in the form of photo-irradiation or thermal processing. Such reactions are highly relevant in cold dense molecular clouds where interactions between neutral species are more favoured.

7.
Abdom Radiol (NY) ; 45(4): 1100-1109, 2020 04.
Article in English | MEDLINE | ID: mdl-32052130

ABSTRACT

PURPOSE: To evaluate the quantitative attenuation and reliability of virtual non-contrast (VNC) images of the abdomen acquired from multiphasic scans with a dual-energy computed tomography (DECT) system and compare it with that of true non-enhanced images (TNC) on second- (Flash) and third- (Force) generation DECT scanners. METHODS: This retrospective study was approved by the institutional review board and included 123 patients with pancreatic cancer who had undergone routine clinical multiphasic DECT examinations at our institution using Flash and Force scanners between March and August 2017. VNC images of the abdomen were reconstructed from late arterial phase images. For every patient, regions-of-interest were defined in the aorta, fluid-containing structures (gallbladder, pleural effusion, and renal cysts > 10 mm), paravertebral muscles, subcutaneous fat, spleen, pancreas, renal cortex, and liver (eight locations) on TNC and VNC images. The mean attenuation of VNC was compared with TNC by organ for each CT scanner using an equivalence test and the Bland-Altman plot. The mean attenuations for TNC or VNC were compared between the Force and Flash CT scanners using a two-sample t test. RESULTS: The VNC attenuation of organs on the Force scanner was lower than was that on the Flash, and the mean attenuation difference in different organs on the Force was closer to 0. The estimated means of TNC and VNC were equivalent for an equivalence margin of 10 on the Force scanner. CONCLUSION: VNC images in DECT are a promising alternative to TNC images. In clinical scenarios in which non-enhanced CT images are required but are not available for accurate diagnosis, VNC images can potentially serve as an alternative to TNC images without the radiation exposure risks.


Subject(s)
Abdomen/diagnostic imaging , Pancreatic Neoplasms/diagnostic imaging , Radiography, Dual-Energy Scanned Projection/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results , Retrospective Studies
8.
J Med Syst ; 44(2): 34, 2019 Dec 18.
Article in English | MEDLINE | ID: mdl-31853735

ABSTRACT

Computer assisted automatic smart pattern analysis of cancer affected pixel structure takes critical role in pre-interventional decision making for oral cancer treatment. Internet of Things (IoT) in healthcare systems is now emerging solution for modern e-healthcare system to provide high quality medical care. In this research work, we proposed a novel method which utilizes a modified vesselness measurement and a Deep Convolutional Neural Network (DCNN) to identify the oral cancer region structure in IoT based smart healthcare system. The robust vesselness filtering scheme handles noise while reserving small structures, while the CNN framework considerably improves classification accuracy by deblurring focused region of interest (ROI) through integrating with multi-dimensional information from feature vector selection step. The marked feature vector points are extracted from each connected component in the region and used as input for training the CNN. During classification, each connected part is individually analysed using the trained DCNN by considering the feature vector values that belong to its region. For a training of 1500 image dataset, an accuracy of 96.8% and sensitivity of 92% is obtained. Hence, the results of this work validate that the proposed algorithm is effective and accurate in terms of classification of oral cancer region in accurate decision making. The developed system can be used in IoT based diagnosis in health care systems, where accuracy and real time diagnosis are essential.


Subject(s)
Decision Support Systems, Clinical/standards , Internet of Things , Mouth Neoplasms/classification , Mouth Neoplasms/diagnostic imaging , Neural Networks, Computer , Algorithms , Deep Learning , Diagnosis, Computer-Assisted/methods , Humans
9.
AJNR Am J Neuroradiol ; 40(9): 1601-1606, 2019 09.
Article in English | MEDLINE | ID: mdl-31439626

ABSTRACT

BACKGROUND AND PURPOSE: Volumetric high-resolution heavily T2-weighted imaging or time-resolved contrast-enhanced MRA is used in the detection and characterization of spinal vascular malformations, though inherent trade-offs can affect their overall sensitivity and accuracy. We compared the efficacy of volumetric high-resolution heavily T2-weighted and time-resolved contrast-enhanced images in spinal vascular malformation diagnosis and feeder characterization and assessed whether a combined evaluation improved the overall accuracy of diagnosis. MATERIALS AND METHODS: Twenty-eight patients with spinal vascular malformations (spinal dural arteriovenous fistula, spinal cord arteriovenous malformation, and perimedullary arteriovenous fistula) were prospectively enrolled. MR images were separately analyzed by 2 neuroradiologists blinded to the final diagnosis. RESULTS: Both sequences demonstrated 100% sensitivity and 93.5% accuracy for the detection of spinal vascular malformations. Volumetric high-resolution heavily T2-weighted imaging was superior to time-resolved contrast-enhanced MR imaging for identification of spinal cord arteriovenous malformations (100% versus 90% sensitivity and 96.7% versus 93.5% accuracy), however, for the diagnosis of perimedullary arteriovenous fistula, time resolved contrast enhanced MRI was found to perform better than the volumetric T2 sequence (80% versus 60% sensitivity and 96.7% versus 93.5% accuracy). Both sequences showed equal sensitivity (100%) and accuracy (87%) for spinal dural arteriovenous fistulas. Combined evaluation improved the overall accuracy across all types of spinal vascular malformation. Volumetric high-resolution heavily T2-weighted imaging was superior or equal to time-resolved contrast-enhanced MR imaging for feeder identification of spinal dural arteriovenous fistulas for both observers (90.9% and 72.7% versus 72.7%), which improved to 90.9% when the sequences were combined. Time-resolved contrast-enhanced MR imaging performed better for major and total feeder identification of spinal cord arteriovenous malformation (80% versus 60%) and perimedullary arteriovenous fistula (80% versus 60%-80%). CONCLUSIONS: Combined volumetric high-resolution heavily T2-weighted imaging and time-resolved contrast-enhanced MR imaging can improve the sensitivity and accuracy of spinal vascular malformation diagnosis, classification, and feeder characterization.


Subject(s)
Arteriovenous Malformations/diagnostic imaging , Magnetic Resonance Angiography/methods , Magnetic Resonance Imaging/methods , Multimodal Imaging/methods , Spinal Cord/diagnostic imaging , Adolescent , Adult , Aged , Arteriovenous Malformations/pathology , Female , Humans , Image Enhancement , Male , Middle Aged , Sensitivity and Specificity , Spinal Cord/pathology , Young Adult
11.
Proc Natl Acad Sci U S A ; 116(5): 1526-1531, 2019 01 29.
Article in English | MEDLINE | ID: mdl-30630945

ABSTRACT

Clathrate hydrates (CHs) are ubiquitous in earth under high-pressure conditions, but their existence in the interstellar medium (ISM) remains unknown. Here, we report experimental observations of the formation of methane and carbon dioxide hydrates in an environment analogous to ISM. Thermal treatment of solid methane and carbon dioxide-water mixture in ultrahigh vacuum of the order of 10-10 mbar for extended periods led to the formation of CHs at 30 and 10 K, respectively. High molecular mobility and H bonding play important roles in the entrapment of gases in the in situ formed 512 CH cages. This finding implies that CHs can exist in extreme low-pressure environments present in the ISM. These hydrates in ISM, subjected to various chemical processes, may act as sources for relevant prebiotic molecules.

13.
Technol Health Care ; 26(2): 379-385, 2018.
Article in English | MEDLINE | ID: mdl-29526864

ABSTRACT

BACKGROUND: Wireless physiological signal monitoring system designing with secured data communication in the health care system is an important and dynamic process. OBJECTIVE: We propose a signal monitoring system using NI myRIO connected with the wireless body sensor network through multi-channel signal acquisition method. Based on the server side validation of the signal, the data connected to the local server is updated in the cloud. The Internet of Things (IoT) architecture is used to get the mobility and fast access of patient data to healthcare service providers. METHODS: This research work proposes a novel architecture for wireless physiological signal monitoring system using ubiquitous healthcare services by virtual Internet of Things. RESULTS: We showed an improvement in method of access and real time dynamic monitoring of physiological signal of this remote monitoring system using virtual Internet of thing approach. This remote monitoring and access system is evaluated in conventional value. This proposed system is envisioned to modern smart health care system by high utility and user friendly in clinical applications. CONCLUSION: We claim that the proposed scheme significantly improves the accuracy of the remote monitoring system compared to the other wireless communication methods in clinical system.


Subject(s)
Internet , Monitoring, Ambulatory/methods , Wireless Technology , Blood Pressure , Body Temperature , Computer Communication Networks , Computer Security , Humans , Oxygen/blood , Pulse , Remote Sensing Technology , Wearable Electronic Devices
14.
Phys Chem Chem Phys ; 20(3): 1838-1847, 2018 Jan 17.
Article in English | MEDLINE | ID: mdl-29292468

ABSTRACT

The phase transition of solid propane and a propane-water mixture under ultrahigh vacuum has been investigated using reflection absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption mass spectrometry (TPD-MS). Here, the investigation is divided into two sections: the phase transition of pure propane and the interaction of propane with water. RAIR spectra of pure propane reveal an unknown crystalline phase at 50 K (phase I), which gradually converts to a known crystalline phase (phase II) at higher temperature. This conversion is associated with certain kinetics. Co-deposition of water and propane restricts the amorphous to crystalline phase transition, while sequential deposition (H2O@C3H8; propane over predeposited water) does not hinder it. For an alternative sequential deposition (C3H8@H2O; water over predeposited propane), the phase transition is hindered due to diffusional mixing within the given experimental time, which is attributed to the reason behind the restricted phase transition.

15.
Int J Tuberc Lung Dis ; 21(8): 916-921, 2017 08 01.
Article in English | MEDLINE | ID: mdl-28786800

ABSTRACT

SETTING: A cohort of household contacts of tuberculosis (TB) index cases from four public health clinics in São Paulo, Brazil. OBJECTIVE: To measure the association between diabetes mellitus (DM) among household contacts and recent-transmission TB (RT TB). DESIGN: Index TB cases (n = 263) identified from 2001 to 2002 in São Paulo, whose household contacts (n = 1383) were monitored for active TB until December 2010. RESULTS: From 2001 to 2010, there were 29 cases of RT TB among household contacts (cumulative incidence 2.1%, 95%CI 1.4-2.9). DM in household contacts was associated with RT TB (OR 3.96, 95%CI 1.33-11.79) even after adjustment for human immunodeficiency virus (HIV) status, smoking and alcohol use (adjusted OR [aOR] 3.21, 95%CI 1.01-10.19). HIV infection was also associated with RT TB (OR 6.40, 95%CI 1.40-29.40; aOR 4.81, 95%CI 0.96-24.18). Household contact DM was not associated with non-RT TB (OR 1.27, 95%CI 0.30-5.40). The time to diagnosis of TB was shorter in household contacts with and without DM (P = 0.035) and in household contacts with and without HIV (P = 0.0002). CONCLUSION: Household contact DM was associated with an increased risk of RT TB in a cohort in Brazil, lending support to the active screening of household contacts with DM for TB in Brazil.


Subject(s)
Contact Tracing , Diabetes Mellitus/epidemiology , HIV Infections/epidemiology , Tuberculosis/epidemiology , Adolescent , Brazil/epidemiology , Family Characteristics , Female , Humans , Incidence , Male , Mass Screening/methods , Risk Factors , Time Factors , Tuberculosis/diagnosis , Tuberculosis/transmission , Young Adult
16.
Genome Announc ; 5(20)2017 May 18.
Article in English | MEDLINE | ID: mdl-28522707

ABSTRACT

We report here the genome sequence of Vibrio campbellii LB102, isolated from the broodstock rearing system of a shrimp hatchery in India. Sequence analysis revealed the presence of effector toxins of the type III (YopT, sharing 39% identity with Yersinia pestis) and type VI (VgrG-3 and hemolysin coregulated protein of V. cholerae) secretion systems.

17.
Virusdisease ; 27(2): 123-9, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27366762

ABSTRACT

Viral encephalopathy and retinopathy otherwise known as viral nervous necrosis (VNN) is a neuropathological condition affecting more than 50 fish species worldwide, mostly marine. Different PCR protocols with specific primers were reported from many countries for confirmation of VNN in fishes. In the present study, two pairs of primers were designed and evaluated for the diagnosis of clinical and subclinical cases of infections from field. These primers designated as BARL-F1/BARL-R1 amplified a 902 bp product in the variable region (T4) of the coat protein gene by first step PCR. Nested PCR primers BARL-F2/BARL-R2 amplified a fragment of 313 bp. The results were comparable with other commonly used primer sets such as F2/R3 and RG668f/RG919r primers. These new primers could detect betanodavirus in standard reference samples containing low, moderate and high viral load. Known positive and negative control samples of fish also revealed a predictive value of 100 % by RT-PCR diagnosis.

18.
Antiviral Res ; 131: 124-30, 2016 07.
Article in English | MEDLINE | ID: mdl-27132538

ABSTRACT

In the present study, a suitable carrier system was developed for the delivery of dsRNA into Penaeus monodon (P. monodon) post larvae to silence the Monodon baculovirus (MBV) structural gene of p74. The carrier system was developed by layer by layer adsorption of oppositely charged chitosan-dextran sulfate, on charged silica nanoparticles. The silica template was removedto produce multilayered hollow nanocapsules (CS-DS) that were utilized for dsRNA loading at an alkaline pH. The capsule's surface was modified by conjugating with shrimp feed for enhanced cellular uptake. In vivo cellular uptake of CS-DS/FITC loaded nanocapsules conjugated with feed was studied after oral administration into post-larvae. The results revealed that the encapsulated FITC was effectively delivered and exhibited a sustained release into the cytoplasm of shrimp post-larvae. The MBV challenge study for structural gene p74was conducted after 3-25 days of post infection (dpi) with respective CS-DS/dsRNA coated with feed. The results showed a significant survival rate of 86.63% and effective gene silencing in P. monodon. Our findings indicated that the delivery of dsRNA using shrimp feed coatedCS-DSnanocapsules could be a novel approach to prevent viral infections in shrimp.


Subject(s)
Baculoviridae/genetics , Gene Silencing , Nanocapsules , Penaeidae/virology , RNA, Double-Stranded/administration & dosage , Animal Feed , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/chemistry , Chitosan/administration & dosage , Chitosan/chemistry , Dextran Sulfate , Genetic Therapy , Larva/virology , Nanocapsules/chemistry , Silicon Dioxide/chemistry
20.
Biotechnol Lett ; 38(4): 689-700, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26712371

ABSTRACT

OBJECTIVES: Involvement of the outer membrane protein C (OmpC) of Escherichia coli in neurodegeneration was investigated using a mouse model. RESULTS: OmpC formed protease-resistant fibres that exhibited the diagnostic features of an amyloid. The spectral shift in the Congo Red and the thioflavin T assays produced features similar to neurotoxic peptides. Intramuscular administration of OmpC in mice resulted in spongiform neurodegeneration of the brain through calcium-dependent apoptosis and also showed upregulation of apoptosis related genes. Immunolocalization of OmpC in brain demonstrated the direct involvement of the porin in neurodegeneration and formation of spongiform encephalopathy. CONCLUSION: We have demonstrated the ability of OmpC of E. coli to induce neurodegeneration in mice.


Subject(s)
Brain/pathology , Neurodegenerative Diseases/etiology , Porins/toxicity , Animals , Apoptosis , Brain/metabolism , Calcium/metabolism , Disease Models, Animal , Gene Expression Regulation , Injections, Intramuscular , Mice , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/pathology , Porins/administration & dosage
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