ABSTRACT
Adult hippocampal neurogenesis is a lifelong process that involves the integration of newborn neurons into the hippocampal network, and plays a role in cognitive function and the modulation of mood-related behavior. Here, we sought to address the impact of chemogenetic activation of adult hippocampal progenitors on distinct stages of progenitor development, including quiescent stem cell activation, progenitor turnover, differentiation and morphological maturation. We find that hM3Dq-DREADD-mediated activation of nestin-positive adult hippocampal progenitors recruits quiescent stem cells, enhances progenitor proliferation, increases doublecortin-positive newborn neuron number, accompanied by an acceleration of differentiation and morphological maturation, associated with increased dendritic complexity. Behavioral analysis indicated anxiolytic behavioral responses in transgenic mice subjected to chemogenetic activation of adult hippocampal progenitors at timepoints when newborn neurons are predicted to integrate into the mature hippocampal network. Furthermore, we noted an enhanced fear memory extinction on a contextual fear memory learning task in transgenic mice subjected to chemogenetic activation of adult hippocampal progenitors. Our findings indicate that hM3Dq-DREAD-mediated chemogenetic activation of adult hippocampal progenitors impacts distinct aspects of hippocampal neurogenesis, associated with the regulation of anxiety-like behavior and fear memory extinction.
ABSTRACT
BACKGROUND: Tuberculosis remains one of the deadliest communicable diseases. Prompt diagnosis of active tuberculosis cases facilitates timely therapeutic intervention and minimizes the community transmission. Although conventional microscopy has low sensitivity, still it remains the corner stone for the diagnosis of pulmonary tuberculosis in high burden countries like India. On the other hand, Nucleic acid amplification techniques due to their rapidity and sensitivity, not only help in early diagnosis and management of tuberculosis but also curtail the transmission of the disease. This study therefore was aimed at assessing the diagnostic performance of Microscopy by Ziehl Neelsen (ZN) and Auramine Staining (AO) with Gene Xpert/CBNAAT (Cartridge based nucleic acid amplification test) in the diagnosis of Pulmonary Tuberculosis. METHODS: A prospective comparative study was done on the sputum samples of 1583 adult patients from November 2018 to May 2020 suspected of having pulmonary tuberculosis as per NTEP criteria visiting the Designated Microscopic Centre of SGT Medical College, Budhera, Gurugram. Each sample was subjected to ZN staining, AO staining, and was run on CBNAAT as per National Tuberculosis Elimination Program (NTEP) guidelines. The sensitivity, specificity, PPV and NPV and Area under the curve of ZN microscopy and Fluorescent Microscopy were calculated taking CBNAAT as reference in absence of culture. RESULTS: Out of the 1583 samples studied, 145 (9.15%) and 197 (12.44%) were positive by ZN and AO staining methods respectively. By CBNAAT 246 (15.54%) samples were positive for M. tuberculosis. AO was also able to detect more pauci-bacillary cases than ZN. While CBNAAT detected M. tuberculosis in 49 sputum samples which were missed by both methods of microscopy. On the other hand there were 9 samples which were positive for AFB by both the smear microscopy techniques but M. tuberculosis was not detected by CBNAAT, these were considered as Non-Tuberculous Mycobacteria. Seventeen samples were resistant to rifampicin. CONCLUSION: Auramine Staining technique is more sensitive and less time consuming for the diagnosis of pulmonary tuberculosis as compared to the conventional ZN Staining. CBNAAT can be a useful tool for early diagnosis of patients with high clinical suspicion of pulmonary tuberculosis and detecting rifampicin resistance.
Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , Adult , Humans , Rifampin , Benzophenoneidum , Prospective Studies , Sputum/microbiology , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/microbiology , Mycobacterium tuberculosis/genetics , Coloring Agents , Sensitivity and SpecificityABSTRACT
BACKGROUND: Electroconvulsive seizure therapy is often used in both treatment-resistant and geriatric depression. However, preclinical studies identifying targets of chronic electroconvulsive seizure (ECS) are predominantly focused on animal models in young adulthood. Given that putative transcriptional, neurogenic, and neuroplastic mechanisms implicated in the behavioral effects of chronic ECS themselves exhibit age-dependent modulation, it remains unknown whether the molecular and cellular targets of chronic ECS vary with age. METHODS: We subjected young adult (2-3 months) and middle-aged (12-13 months), male Sprague Dawley rats to sham or chronic ECS and assessed for despair-like behavior, hippocampal gene expression, hippocampal neurogenesis, and neuroplastic changes in the extracellular matrix, reelin, and perineuronal net numbers. RESULTS: Chronic ECS reduced despair-like behavior at both ages, accompanied by overlapping and unique changes in activity-dependent and trophic factor gene expression. Although chronic ECS had a similar impact on quiescent neural progenitor numbers at both ages, the eventual increase in hippocampal progenitor proliferation was substantially higher in young adulthood. We noted a decline in reelin⺠cell numbers following chronic ECS only in young adulthood. In contrast, an age-invariant, robust dissolution of perineuronal net numbers that encapsulate parvalbumin⺠neurons in the hippocampus were observed following chronic ECS. CONCLUSION: Our findings indicate that age is a key variable in determining the nature of chronic ECS-evoked molecular and cellular changes in the hippocampus. This raises the intriguing possibility that chronic ECS may recruit distinct, as well as overlapping, mechanisms to drive antidepressant-like behavioral changes in an age-dependent manner.
Subject(s)
Electroconvulsive Therapy , Hippocampus , Rats , Animals , Male , Rats, Sprague-Dawley , Electroshock , Seizures/metabolism , Gene ExpressionABSTRACT
Respiratory syncytial virus (RSV) has been identified as a leading cause of lower respiratory tract infections in young children and elderly. It is an enveloped negative-sense RNA virus belonging to Genus Orthopneumovirus. The clinical features of RSV infection range from mild upper-respiratory-tract illnesses or otitis media to severe lower-respiratory-tract illnesses. Current estimates show that about 33.1 million episodes of RSV-acute lower respiratory infection (ALRI) occurred in young children in 2015, of these majority that is, about 30 million RSV-ALRI episodes occurred in low-middle-income countries. In India, the rates of RSV detection in various hospital- and community-based studies mostly done in children vary from 5% to 54% and from 8% to 15%, respectively. Globally, RSV epidemics start in the South moving to the North. In India, RSV mainly peaks in winter in North India and some correlation with low temperature has been observed. Different genotypes of Group A (GA2, GA5, NA1 and ON1) and Group B (GB2, SAB4 and BA) have been described from India. The burden of RSV globally has kept it a high priority for vaccine development. After nearly 50 years of attempts, there is still no licensed vaccine and challenges to obtain a safe and effective vaccine is still facing the scientific community. The data in this review have been extracted from PubMed using the keywords RSV and Epidemiology and India. The data have been synthesised by the authors.
Subject(s)
Disease Transmission, Infectious/prevention & control , Genotype , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Vaccines/immunology , Respiratory Syncytial Viruses/classification , Respiratory Syncytial Viruses/immunology , Humans , India/epidemiology , Prevalence , Respiratory Syncytial Viruses/isolation & purification , SeasonsABSTRACT
Huntington's disease (HD) is an inherited neurodegenerative disorder caused by abnormal expansion of CAG repeats in the gene encoding huntingtin. Mutant huntingtin undergoes proteolytic processing and its N-terminal fragment containing polyglutamine repeat accumulates as inclusion not only in nucleus but also in cytoplasm and neuronal processes. Here, we demonstrate that removal of ubiquitin ligase Ube3a selectively from HD mice brain resulted in accelerated disease phenotype and shorter lifespan in comparison with HD mice. The deficiency of Ube3a in HD mice brain also caused significant increase in global aggregates load, and these aggregates were less ubiquitinated when compared with age-matched HD mice. These Ube3a-maternal deficient HD mice also showed drastic reduction of DARPP-32, a dopamine-regulated phoshphoprotein in their striatum. These results emphasize the crucial role of Ube3a in the progression of HD and its immense potential as therapeutic target.
Subject(s)
Brain/pathology , Huntington Disease/genetics , Protein Aggregates , Ubiquitin-Protein Ligases/genetics , Animals , Body Weight/genetics , Brain/metabolism , Corpus Striatum/metabolism , Corpus Striatum/pathology , Dopamine and cAMP-Regulated Phosphoprotein 32/metabolism , Female , Huntingtin Protein , Huntington Disease/metabolism , Huntington Disease/mortality , Male , Mice , Mice, Transgenic , Motor Activity , Nerve Tissue Proteins/metabolism , Nuclear Proteins/metabolism , UbiquitinationABSTRACT
Huntington's disease (HD) is an inherited neurodegenerative disorder caused by abnormal expansion of glutamine repeats in the protein huntingtin. In HD brain, mutant huntingtin undergoes proteolytic processing, and its N-terminal fragment containing poly-glutamine repeats accumulate as insoluble aggregates leading to the defect in cellular protein quality control system and heat shock response (HSR). Here we demonstrate that the defective HSR in the brain is due to the down-regulation of heat shock factor 1 (HSF1) in both mice and fly models of HD. Interestingly, treatment of dexamethasone (a synthetic glucocorticoid) to HD mice or flies significantly increased the expression and transactivation of HSF1 and induction of HSR and these effects are mediated through the down-regulation of HSP90. Dexamethasone treatment also significantly decreased the aggregate load and transient recovery of HD-related behavioural phenotypes in both disease models. These results suggest that dexamethasone could be a potential therapeutic molecule for the treatment of HD and related poly-glutamine disorders.
Subject(s)
Dexamethasone/pharmacology , Glucocorticoids/pharmacology , Heat-Shock Response/drug effects , Huntington Disease/drug therapy , Animals , Brain/metabolism , Cell Line , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Dexamethasone/therapeutic use , Disease Models, Animal , Disease Progression , Drosophila , Drug Evaluation, Preclinical , Female , Glucocorticoids/therapeutic use , HSP70 Heat-Shock Proteins/metabolism , Heat Shock Transcription Factors , Humans , Huntington Disease/metabolism , Male , Mice, Inbred C57BL , Mice, Transgenic , Psychomotor Performance/drug effects , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptional ActivationABSTRACT
Despite being curable reproductive tract infections (RTIs) including sexually transmitted infections continue to be a major health problem in developing countries. The present study was undertaken to know the prevalence of trichomoniasis, vaginal candidiasis, genital herpes, chlamydiasis, and actinomycosis in rural and urban women of Haryana by using wet mount, PAP smear, and fluorescent microscopic examination. Patients suspected of suffering from bacterial vaginosis were given treatment and were not included in the study. RTIs were seen in 16.6% of urban and 28.7% of rural women. The highest prevalence seen was that of trichomoniasis in both rural (24.2%) and urban (15.7%) women, followed by candidiasis (4.2% in rural and 0.6% in urban women), genital herpes (0.3% in rural and 0.2% in urban women), and chlamydiasis (0.02% in rural and 0.05% in urban women). Pelvic actinomycosis was seen in 1.4% of rural and 0.06% of urban women using intrauterine contraceptive devices. Mixed infection of Trichomonas vaginalis with Candida spp. was seen in 6.3% of rural women only. It is desirable to have a baseline profile of the prevalence of various agents causing RTIs in a particular geographic area and population which will help in better syndromic management of the patients.
ABSTRACT
Reversing and arresting the epidemic of HIV are a challenge for any country. Early diagnosis and rapid initiation of treatment remain a key strategy in the control of HIV. Technological advances in the form of low-cost rapid point-of-care tests have completely transformed the diagnosis and management of HIV, especially in resource limited settings, where health infrastructure is poor and timely access to medical care is a challenge. Point-of-care devices have proven to be easy to transport, operate, and maintain, and also lower-skilled staff is equally able to perform these tests as compared to trained laboratory technicians. Point-of-care tests allow rapid detection of HIV allowing for rapid initiation of therapy, monitoring of antiretroviral therapy and drug toxicity, and detection of opportunistic infections and associated illnesses.
ABSTRACT
Fusarium species are common soil-inhabiting organisms and plant pathogens. Human infections are usually precipitated by local or systemic predisposing factors, and disseminated infection is associated with impaired immune responses. Skin infections caused by Fusarium spp. include keratitis, onychomycosis, mycetoma, painful discrete erythematous nodules. Hyperkeratotic skin lesions caused by Fusarium spp. are, however, rarely reported. We report a case of hyperkeratotic verrucous warty skin lesion in the foot of a 50-year-old immunocompetent male, farmer by occupation.
ABSTRACT
Protein aggregation and ordered fibrillar amyloid deposition inside and outside of the central nervous system cells is the common pathologic hallmark of most aging-related neurodegenerative disorders. Dominant mutations in the gene encoding superoxide dismutase 1 (SOD1) protein are linked to familial amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive degeneration of motor neurons, leading to muscle paralysis and death. The major histochemical hallmark in the remaining motor neurons of ALS is the intracellular accumulation of ubiquitinated inclusions consisting of insoluble aberrant protein aggregates. However, the molecular pathomechanisms underlying the process have been elusive. Here for the first time, we report that E6-AP, a homologous to E6-AP C terminus-type E3 ubiquitin ligase depleted in ALS mouse models before neurodegeneration. E6-AP coimmunoprecipitates with the SOD1 protein and is predominantly mislocalized in mutant SOD1-containing inclusion bodies. Overexpression of E6-AP increases the ubiquitination and facilitates degradation of SOD1 proteins. Finally, we show that the overexpression of E6-AP suppresses the aggregation and cell death mediated by mutated SOD1 proteins and cellular protective effect is more prominent when E6-AP is overexpressed along with Hsp70. These data suggest that enhancing the activity of E6-AP ubiquitin ligase might be a viable therapeutic strategy to eliminate mutant SOD1-mediated toxicity in ALS.
Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Inclusion Bodies/metabolism , Neurons/metabolism , Superoxide Dismutase/metabolism , Ubiquitin-Protein Ligases/metabolism , Amyotrophic Lateral Sclerosis/pathology , Animals , Cell Aggregation , Cell Survival , Cells, Cultured , Mice , Mice, Transgenic , Superoxide Dismutase-1ABSTRACT
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ABSTRACT
Huntington disease (HD) is a hereditary neurodegenerative disorder characterized by progressive cognitive, psychiatric, and motor symptoms. The disease is caused by abnormal expansion of CAG repeats in the gene encoding huntingtin, but how mutant huntingtin leads to early cognitive deficits in HD is poorly understood. Here, we demonstrate that the ubiquitin ligase Ube3a, which is implicated in synaptic plasticity and involved in the clearance of misfolded polyglutamine protein, is strongly recruited to the mutant huntingtin nuclear aggregates, resulting in significant loss of its functional pool in different regions of HD mouse brain. Interestingly, Arc, one of the substrates of Ube3a linked with synaptic plasticity, is also associated with nuclear aggregates, although its synaptic level is increased in the hippocampus and cortex of HD mouse brain. Different regions of HD mouse brain also exhibit decreased levels of AMPA receptors and various pre- and postsynaptic proteins, which could be due to the partial loss of function of Ube3a. Transient expression of mutant huntingtin in mouse primary cortical neurons further demonstrates recruitment of Ube3a into mutant huntingtin aggregates, increased accumulation of Arc, and decreased numbers of GluR1 puncta in the neuronal processes. Altogether, our results suggest that the loss of function of Ube3a might be associated with the synaptic abnormalities observed in HD.
Subject(s)
Huntington Disease/enzymology , Huntington Disease/physiopathology , Synapses/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , Cerebral Cortex/enzymology , Cerebral Cortex/pathology , Cerebral Cortex/physiopathology , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , Disease Models, Animal , Female , Hippocampus/enzymology , Hippocampus/pathology , Hippocampus/physiopathology , Humans , Huntingtin Protein , Huntington Disease/genetics , Mice , Mice, Transgenic , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neuronal Plasticity/genetics , Neurons/enzymology , Neurons/pathology , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Protein Folding , Receptors, AMPA/genetics , Receptors, AMPA/metabolism , Synapses/genetics , Synapses/pathology , Trinucleotide Repeat Expansion , Ubiquitin-Protein Ligases/geneticsABSTRACT
Angelman syndrome (AS) is a neurodevelopmental disorder caused due to deletions or loss-of-function mutations in maternally inherited UBE3A. Ube3a functions as an ubiquitin ligase as well as a transcriptional coactivator of steroid hormone receptors. However, the mechanisms by which maternal Ube3a deficiency gives rise to phenotypic features of AS are not clear. We report here that Ube3a regulates glucocorticoid receptor (GR) transactivation and GR signaling pathway is disrupted in Ube3a-maternal-deficient mice brain. The expression of several GR-dependent genes is down-regulated in multiple brain regions of Ube3a-maternal-deficient mice. AS mice show significantly higher level of blood corticosterone, selective loss of GR and reduced number of parvalbumin-positive inhibitory interneurons in their hippocampus that could ultimately lead to increased stress. These mice also exhibit increased anxiety-like behavior, which could be due to chronic stress. Altogether, our findings suggest that chronic stress due to altered GR signaling might lead to anxiety-like behavior in a mouse of model of AS.
Subject(s)
Angelman Syndrome/metabolism , Angelman Syndrome/psychology , Anxiety/etiology , Brain/metabolism , Receptors, Glucocorticoid/metabolism , Stress, Psychological/etiology , Ubiquitin-Protein Ligases/metabolism , Amygdala/metabolism , Angelman Syndrome/pathology , Animals , Disease Models, Animal , GABAergic Neurons/chemistry , GABAergic Neurons/physiology , Hippocampus/pathology , Immediate-Early Proteins/metabolism , Interneurons/chemistry , Interneurons/physiology , Mice , Parvalbumins/analysis , Protein Serine-Threonine Kinases/metabolism , Receptors, Glucocorticoid/genetics , Signal Transduction , Transcriptional Activation , Ubiquitin-Protein Ligases/geneticsABSTRACT
CASE: We are presenting a 50-year-old patient of pulmonary tuberculosis, on anti-tuberculosis therapy (ATT) for last 2 months who presented with fever, cough, breathlessness, anorexia, and weight loss. The case was found to be HIV reactive. His sputum sample showed Candida albicans and Pneumocystis jirovecii. Fluconazole and cotrimoxazole + sulphamethoxazole were added. The index case did not respond to the treatment and his clinical condition started to deteriorate and he developed headache, vomiting, and dysphagia. Repeat sputum sample and cerebrospinal fluid (CSF) showed Cryptococcus neoformans which was found to be sensitive to Amphotericin B. Amphotericin B was added to the treatment and patient clinically responded to treatment. In conclusion, emphasis should be given to correct etiological identification, allowing appropriate treatment and decreasing the morbidity and mortality in these patients as concomitant opportunistic infections may cause diagnostic problems.
Subject(s)
Antifungal Agents , Pneumonia, Pneumocystis , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , HIV Infections/drug therapy , Humans , Meningitis, Cryptococcal/diagnosis , Tuberculosis, PulmonaryABSTRACT
Mycoplasma pneumoniae is known to be a major cause of lower respiratory tract infections (LRTIs) in children. We studied 75 children who had been hospitalized for community-acquired LRTIs for the detection of M. pneumoniae by serological analysis and polymerase chain reaction (PCR) to amplify a 277-base pair region of 16S rDNA gene of M. pneumoniae applied to throat swab specimens. Serological and/or PCR positive results diagnosed M. pneumoniae infection in 23 (30.7%) patients.
Subject(s)
Mycoplasma pneumoniae/isolation & purification , Pneumonia, Mycoplasma/diagnosis , Pneumonia, Mycoplasma/microbiology , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/microbiology , Antibodies, Bacterial/blood , Child , Child, Preschool , Community-Acquired Infections/diagnosis , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Female , Humans , India/epidemiology , Infant , Male , Mycoplasma pneumoniae/genetics , Mycoplasma pneumoniae/immunology , Pharynx/microbiology , Pneumonia, Mycoplasma/epidemiology , Polymerase Chain Reaction/methods , Prevalence , Respiratory Tract Infections/epidemiologyABSTRACT
Mycoplasma pneumoniae is known to be the chief causative organism for community-acquired non-lobar pneumonia in children of 5-15 years of age. M. pneumoniae as an aetiological agent for pneumonia among neonates and infants has rarely been reported. We report here a case of persistent pneumonia due to M. pneumoniae in a 3-week-old neonate.
Subject(s)
Mycoplasma pneumoniae/isolation & purification , Pneumonia, Mycoplasma/diagnosis , Pneumonia, Mycoplasma/drug therapy , Anti-Bacterial Agents/therapeutic use , Erythromycin/therapeutic use , Humans , Infant, Newborn , Male , Pneumonia, Mycoplasma/microbiology , Treatment OutcomeABSTRACT
Cells are equipped with an efficient quality control system to selectively eliminate abnormally folded and damaged proteins. Initially the cell tries to refold the unfolded proteins with the help of molecular chaperones, and failure to refold leads to their degradation by the ubiquitin proteasome system. But how this proteolytic machinery recognizes the abnormally folded proteins is poorly understood. Here, we report that E6-AP, a HECT domain family ubiquitin ligase implicated in Angelman syndrome, interacts with the substrate binding domain of Hsp70/Hsc70 chaperones and promotes the degradation of chaperone bound substrates. The expression of E6-AP was dramatically induced under a variety of stresses, and overexpression of E6-AP was found to protect against endoplasmic reticulum stress-induced cell death. The inhibition of proteasome function not only increases the expression of E6-AP but also causes its redistribution around microtubule-organizing center, a subcellular structure for the degradation of the cytoplasmic misfolded proteins. E6-AP is also recruited to aggresomes containing the cystic fibrosis transmembrane conductance regulator or expanded polyglutamine proteins. Finally, we demonstrate that E6-AP ubiquitinates misfolded luciferase that is bound by Hsp70. Our results suggest that E6-AP functions as a cellular quality control ubiquitin ligase and, therefore, can be implicated not only in the pathogenesis of Angelman syndrome but also in the biology of neurodegenerative disorders involving protein aggregation.
Subject(s)
Angelman Syndrome/metabolism , HSP70 Heat-Shock Proteins/metabolism , Proteasome Inhibitors , Ubiquitin-Protein Ligases/metabolism , Ubiquitin/metabolism , Animals , Cell Death/physiology , Cell Line , Cysteine Proteinase Inhibitors/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , HSP70 Heat-Shock Proteins/genetics , Hot Temperature , Humans , Leupeptins/metabolism , Luciferases/genetics , Luciferases/metabolism , Peptides/metabolism , Proteasome Endopeptidase Complex/metabolism , Protein Folding , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , UbiquitinationABSTRACT
PURPOSE: To investigate whether the variable forms of putative iron deposition seen with susceptibility weighted imaging (SWI) will lead to a set of multiple sclerosis (MS) lesion characteristics different than that seen in conventional MR imaging. MATERIALS AND METHODS: Twenty-seven clinically definite MS patients underwent brain scans using magnetic resonance imaging including: pre- and postcontrast T1-weighted imaging, T2-weighted imaging, FLAIR, and SWI at 1.5 T, 3 T, and 4 T. MS lesions were identified separately in each imaging sequence. Lesions identified in SWI were reevaluated for their iron content using the SWI filtered phase images. RESULTS: There were a variety of new lesion characteristics identified by SWI, and these were classified into six types. A total of 75 lesions were seen only with conventional imaging, 143 only with SWI, and 204 by both. From the iron quantification measurements, a moderate linear correlation between signal intensity and iron content (phase) was established. CONCLUSION: The amount of iron deposition in the brain may serve as a surrogate biomarker for different MS lesion characteristics. SWI showed many lesions missed by conventional methods and six different lesion characteristics. SWI was particularly effective at recognizing the presence of iron in MS lesions and in the basal ganglia and pulvinar thalamus.
Subject(s)
Brain/metabolism , Brain/pathology , Iron/metabolism , Magnetic Resonance Imaging/methods , Multiple Sclerosis/metabolism , Multiple Sclerosis/pathology , Adult , Aged , Biomarkers/metabolism , Brain Mapping/methods , Contrast Media , Echo-Planar Imaging/methods , Female , Humans , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Male , Middle Aged , Multiple Sclerosis/diagnosis , Young AdultABSTRACT
Telemedicine allows medical doctors and specialized skilled experts to provide services to patients who are in remote locations using advanced telecommunications. This paper presents a taxonomy that systematically classifies various telemedicine efforts worldwide using five major dimensions: application purpose, application area, environmental setting, communication infrastructure, and delivery options. To identify relationships and patterns between these different dimensions telemedicine programs survey data from the Telemedicine Information Exchange (TIE) was analyzed using multiple regression and path analysis. Major findings indicate that interactive video is the most preferred modality. Store-and-forward technology is preferred for ophthalmology, radiology, and pathology. However, a negative correlation exists between store-and-forward and interactive video with mental health application. The study also indicates that the Internet is still not the dominant communications infrastructure when it comes to telemedicine. We showed that these dimensions can capture almost all efforts in telemedicine and also help program planners to understand the issues in telemedicine deployment. Our findings indicate that the taxonomy is useful for categorizing and comparing existing programs, and can be used for planning future programs.