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1.
Indian J Community Med ; 47(2): 207-212, 2022.
Article in English | MEDLINE | ID: mdl-36034257

ABSTRACT

Context: In the absence of any specific treatment available for COVID-19, people started practicing traditional nonpharmacological preventive home remedies such as salt water gargling and steam inhalation. The available research evidence on some of these measures opines that steam inhalation, saline gargling, and povidone-iodine gargling does have virucidal properties and do provide symptomatic relief. Aims: The aim is to test this hypothesis, and the present trial was undertaken with an objective to assess the effect of steam inhalation, saline gargling, and povidone-iodine gargling among the COVID-19-positive patients with respect to early test negativity and clinical recovery. Methodology: Open-labeled, parallel, randomized controlled trial was conducted among asymptomatic or mild COVID-19-positive patients in Bangalore from September 2020 to February 2021. In each group of steam inhalation, saline gargling, povidone-iodine gargling, and control, twenty participants were allocated. Daily follow-up was done for 21 days to assess early test negativity and clinical recovery. Trial Registry Number: Clinical Trial Registry India/2020/09/027687. Results: Among 80 participants recruited, 65 (81.3%) were symptomatic. Early test negativity was seen in povidone-iodine gargling group of 6 days (KaplanMeier survival curve, BreslowGeneralized Wilcoxon test P = 0.7 as per the intention-to-treat and as per-protocol P = 0.8). Significant clinical recovery was seen in saline gargling group (4 days, P = 0.01). Conclusion: Povidone-iodine gargling was effective in providing early test negativity, whereas saline gargling was effective in early clinical recovery.

2.
Med Biol Eng Comput ; 60(9): 2681-2691, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35834050

ABSTRACT

Deep learning provides the healthcare industry with the ability to analyse data at exceptional speeds without compromising on accuracy. These techniques are applicable to healthcare domain for accurate and timely prediction. Convolutional neural network is a class of deep learning methods which has become dominant in various computer vision tasks and is attracting interest across a variety of domains, including radiology. Lung diseases such as tuberculosis (TB), bacterial and viral pneumonias, and COVID-19 are not predicted accurately due to availability of very few samples for either of the lung diseases. The disease could be easily diagnosed using X-ray or CT scan images. But the number of images available for each of the disease is not as equally as other resulting in imbalance nature of input data. Conventional supervised machine learning methods do not achieve higher accuracy when trained using a lesser amount of COVID-19 data samples. Image data augmentation is a technique that can be used to artificially expand the size of a training dataset by creating modified versions of images in the dataset. Data augmentation helped reduce overfitting when training a deep neural network. The SMOTE (Synthetic Minority Oversampling Technique) algorithm is used for the purpose of balancing the classes. The novelty in this research work is to apply combined data augmentation and class balance techniques before classification of tuberculosis, pneumonia, and COVID-19. The classification accuracy obtained with the proposed multi-level classification after training the model is recorded as 97.4% for TB and pneumonia and 88% for bacterial, viral, and COVID-19 classifications. The proposed multi-level classification method produced is ~8 to ~10% improvement in classification accuracy when compared with the existing methods in this area of research. The results reveal the fact that the proposed system is scalable to growing medical data and classifies lung diseases and its sub-types in less time with higher accuracy.


Subject(s)
COVID-19 , Deep Learning , Lung Diseases , Pneumonia, Viral , Tuberculosis , Humans , Pneumonia, Viral/diagnostic imaging
3.
Int J Clin Pediatr Dent ; 15(4): 438-441, 2022.
Article in English | MEDLINE | ID: mdl-36875981

ABSTRACT

Aim: The present study aimed to assess and evaluate oral hygiene status and oral hygiene behaviors among children with the attention-deficit hyperactive disorder (ADHD) and children without ADHD. Materials and methods: A total of 34 children of ages 6-14 years were included in the study. Groups I-17 children with ADHD and group II-17 healthy children. A visual examination of dental caries and traumatic injuries was performed, and the oral hygiene status of these children was determined. The parent/guardian completed a structured questionnaire regarding the child's oral hygiene practices and food habits. Data obtained from oral examination and questionnaires were compiled and subjected to statistical analysis. Results: The student t-test and the Chi-squared test showed that children with ADHD had significantly higher decayed, missing, and filled teeth (DMFT) scores and incidence of traumatic injuries without significant difference in oral hygiene status. Conclusion: There is no significant difference in oral hygiene status between both the groups but caries experience, and incidence of traumatic injuries are high in children with ADHD. How to cite this article: Reddy ER, Kiranmayi M, Mudusu SP, et al. Oral Health Status and Caries Experience in Children Diagnosed with Attention-deficit Hyperactive Disorder. Int J Clin Pediatr Dent 2022;15(4):438-441.

4.
J Med Ultrasound ; 29(3): 218-220, 2021.
Article in English | MEDLINE | ID: mdl-34729335

ABSTRACT

Nonalcoholic pancreatogenic diabetes mellitus (type 3c DM) is an often-misdiagnosed entity usually seen in young men of tropical countries. Although most of the patients present with abdominal pain and symptoms of exocrine pancreatic insufficiency, there is still a subset that does not present with these classical symptoms, which emphasizes the need for special diagnostic considerations. The significance of identifying this subset of diabetic lies not only in the change in management of the disease but also in early detection for pancreatic carcinoma that is more common among those patients. In our case, ultrasound with X-ray played a vital role in diagnosis, prompting us to consider it as an essential part of the investigation panel in all newly diagnosed nonobese diabetic individuals.

5.
Sci Rep ; 10(1): 21214, 2020 12 03.
Article in English | MEDLINE | ID: mdl-33273580

ABSTRACT

Biology is adapted to Earth's gravity force, and the long-term effects of varying gravity on the development of animals is unclear. Previously, we reported that high gravity, called hypergravity, increases defects in the development of motor neuron axons in the nematode Caenorhabditis elegans. Here, we show that a mutation in the unc-70 gene that encodes the cytoskeletal ß-spectrin protein suppresses hypergravity-induced axon defects. UNC-70 expression is required in both muscle and epidermis to promote the axon defects in high gravity. We reveal that the location of axon defects is correlated to the size of the muscle cell that the axon traverses. We also show that mutations that compromise key proteins of hemidesmosomal structures suppress hypergravity-induced axon defects. These hemidesmosomal structures play a crucial role in coupling mechanical force between the muscle, epidermis and the external cuticle. We speculate a model in which the rigid organization of muscle, epidermal and cuticular layers under high gravity pressure compresses the narrow axon migration pathways in the extracellular matrix hindering proper axon pathfinding of motor neurons.


Subject(s)
Axons , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/metabolism , Hypergravity , Motor Neurons/metabolism , Spectrin/metabolism , Animals , Animals, Genetically Modified , Caenorhabditis elegans Proteins/genetics , Epidermis/metabolism , Muscles/metabolism , Spectrin/genetics
6.
Epidemiol Infect ; 148: e230, 2020 09 25.
Article in English | MEDLINE | ID: mdl-32972463

ABSTRACT

We used social network analysis (SNA) to study the novel coronavirus (COVID-19) outbreak in Karnataka, India, and to assess the potential of SNA as a tool for outbreak monitoring and control. We analysed contact tracing data of 1147 COVID-19 positive cases (mean age 34.91 years, 61.99% aged 11-40, 742 males), anonymised and made public by the Karnataka government. Software tools, Cytoscape and Gephi, were used to create SNA graphics and determine network attributes of nodes (cases) and edges (directed links from source to target patients). Outdegree was 1-47 for 199 (17.35%) nodes, and betweenness, 0.5-87 for 89 (7.76%) nodes. Men had higher mean outdegree and women, higher mean betweenness. Delhi was the exogenous source of 17.44% cases. Bangalore city had the highest caseload in the state (229, 20%), but comparatively low cluster formation. Thirty-four (2.96%) 'super-spreaders' (outdegree ⩾ 5) caused 60% of the transmissions. Real-time social network visualisation can allow healthcare administrators to flag evolving hotspots and pinpoint key actors in transmission. Prioritising these areas and individuals for rigorous containment could help minimise resource outlay and potentially achieve a significant reduction in COVID-19 transmission.


Subject(s)
Contact Tracing/methods , Coronavirus Infections/epidemiology , Pneumonia, Viral/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19 , Child , Child, Preschool , Communicable Disease Control , Coronavirus Infections/prevention & control , Female , Humans , India/epidemiology , Infant , Infant, Newborn , Male , Middle Aged , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Social Networking , Software , Young Adult
7.
Physiol Plant ; 167(3): 282-301, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30883793

ABSTRACT

Somatic embryogenesis (SE) is a complex stress related process regulated by numerous biological factors. SE is mainly applicable to mass propagation and genetic improvement of plants through gene transfer technology and induced mutations. In banana, SE is highly genome dependent as the efficiency varies with cultivars. To understand the molecular mechanism of SE, a proteomics approach was carried out to identify proteins expressed during embryogenic calli (EC) induction, regeneration and germination of somatic embryos in the banana cultivar cv. Rasthali (AAB). In total, 70 spots were differentially expressed in various developmental stages of SE, of which 16 were uniquely expressed and 17 were highly abundant in EC compared to non-embryogenic calli and explants. Also, four spots were uniquely expressed in germinating somatic embryos. The functional annotation of identified proteins revealed that calcium signaling along with stress and endogenous hormones related proteins played a vital role in EC induction and germination of somatic embryos. Thus, based on this outcome, the callus induction media was modified and tested in five cultivars. Among them, cultivars Grand Naine (AAA), Monthan (ABB) and Ney Poovan (AB) showed a better response in tryptophan added media, whereas Red Banana (AAA) and Karpuravalli (ABB) showed maximum EC induction in kinetin and CaCl2 supplemented media respectively. Simultaneously, germination media were modified to induce proteins responsible for germination. In cv. Rasthali, media supplemented with 10 mM CaCl2 showed a maximum increase in germination (51.79%) over control plants. Thus, the present study revealed that media modification based on proteomic analysis can induce SE in recalcitrant cultivars and also enhance germination in cultivars amenable for SE.


Subject(s)
Musa/embryology , Musa/metabolism , Plant Somatic Embryogenesis Techniques/methods , Proteomics/methods , Seeds/embryology , Seeds/metabolism , Germination/genetics , Germination/physiology , Plant Proteins/genetics , Plant Proteins/metabolism
8.
Asian Pac J Cancer Prev ; 18(11): 3143-3148, 2017 11 26.
Article in English | MEDLINE | ID: mdl-29172292

ABSTRACT

Detection of lung cancer through image processing is an important tool for diagnosis. In recent years, image processing techniques have become more widely used. Lung segmentation is an essential pre-processing step for most (CAD) schemes. An automated system is proposed in this paper for identifying lung cancer from the analysis of computed tomography images by performing nodule segmentation using an optimal critical point selection algorithm (OCPS) which improves the detection of shape- and size-based juxtapleural nodules located at the lung boundary. A suspect area of nodule is obtained with the help of a bidirectional chain code (BDC) approach and the OCPS This algorithm is used to reduce the time consumption to detect the lung nodule and thereby reduce the computational complexity. Shape and size features are extracted for the area between two critical points to facilitate classification as nodule or non-nodule with the help of a support vector machine and random forest classifiers. This automated method was tested on computed tomography (CT) studies from the lung imaging database consortium (LIDC). The results are compared with the existing techniques using various performance measures such as precision rate, recall rate, accuracy and F-measure. The obtained experimental results indicate that the OCPS combined with a random forest classifier performs better in terms of performance evaluation metrics than existing approaches, with less requirement for computation.

9.
J Mol Model ; 19(10): 4337-48, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23907551

ABSTRACT

Exponential growth in the number of available protein sequences is unmatched by the slower growth in the number of structures. As a result, the development of efficient and fast protein secondary structure prediction methods is essential for the broad comprehension of protein structures. Computational methods that can efficiently determine secondary structure can in turn facilitate protein tertiary structure prediction, since most methods rely initially on secondary structure predictions. Recently, we have developed a fast learning optimized prediction methodology (FLOPRED) for predicting protein secondary structure (Saraswathi et al. in JMM 18:4275, 2012). Data are generated by using knowledge-based potentials combined with structure information from the CATH database. A neural network-based extreme learning machine (ELM) and advanced particle swarm optimization (PSO) are used with this data to obtain better and faster convergence to more accurate secondary structure predicted results. A five-fold cross-validated testing accuracy of 83.8 % and a segment overlap (SOV) score of 78.3 % are obtained in this study. Secondary structure predictions and their accuracy are usually presented for three secondary structure elements: α-helix, ß-strand and coil but rarely have the results been analyzed with respect to their constituent amino acids. In this paper, we use the results obtained with FLOPRED to provide detailed behaviors for different amino acid types in the secondary structure prediction. We investigate the influence of the composition, physico-chemical properties and position specific occurrence preferences of amino acids within secondary structure elements. In addition, we identify the correlation between these properties and prediction accuracy. The present detailed results suggest several important ways that secondary structure predictions can be improved in the future that might lead to improved protein design and engineering.


Subject(s)
Computer Simulation , Proteins/chemistry , Amino Acid Sequence , Hydrogen Bonding , Knowledge Bases , Models, Molecular , Neural Networks, Computer , Protein Structure, Secondary
10.
J Environ Biol ; 33(3): 579-84, 2012 May.
Article in English | MEDLINE | ID: mdl-23029906

ABSTRACT

The growth, yield, and carbon content of eight-month old seedlings of Pongamia pinnata were compared under water and urea supplementation. One set of plants were subjected to water stress condition (WS), whereas the other supplied with 2 g of urea (WS+U) under WS. Both the experimental set ups were exposed to varying treatment levels which include full irrigation (100%, control) followed by 75% (T1), 50% (T2), 25% (T3) and 12.5% (T4). The growth, leaf area and relative water content were maximum under WS when compared to WS+U (p < 0.001). The maximum biomass was produced in the seedlings under WS in control (1.68 g) followed by T1 (1.38 g), T2 (1.53 g), T3 (0.93 g) and T4 (0.73 g). A significant (p < 0.001) reduction in biomass production was observed in WS+U in control (1.28 g), T1 (0.66 g), T2 (1.13 g) and T3 (0.44 g). T4 of WS+U showed similar biomass (0.73 g) as that of T4 of WS. Under WS, the highest biomass allocation was recorded in shoots followed by leaves and roots. Similar trend was observed in WS+U. However, the percentage of allocation was more in the roots of WS+U (27.2%) when compared to WS (22.24 %). The highest amount of carbon content was observed in control plants treated under WS (9.59 g) followed by control plants of WS+U (7.31 g) (p < 0.001). The results of the preliminary study clearly indicated that P. pinnata seedlings were able to cope-up with water stress conditions without urea application and can perform well in 50% water availability and is best suited for the plantation programs in the semi-arid ecosystems.


Subject(s)
Biomass , Carbon/metabolism , Dehydration , Millettia/growth & development , Urea/pharmacology , Fertilizers , Forestry , Millettia/drug effects , Millettia/metabolism , Seedlings/drug effects , Seedlings/growth & development , Seedlings/metabolism
11.
J Mol Model ; 18(9): 4275-89, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22562230

ABSTRACT

Computational methods are rapidly gaining importance in the field of structural biology, mostly due to the explosive progress in genome sequencing projects and the large disparity between the number of sequences and the number of structures. There has been an exponential growth in the number of available protein sequences and a slower growth in the number of structures. There is therefore an urgent need to develop computational methods to predict structures and identify their functions from the sequence. Developing methods that will satisfy these needs both efficiently and accurately is of paramount importance for advances in many biomedical fields, including drug development and discovery of biomarkers. A novel method called fast learning optimized prediction methodology (FLOPRED) is proposed for predicting protein secondary structure, using knowledge-based potentials combined with structure information from the CATH database. A neural network-based extreme learning machine (ELM) and advanced particle swarm optimization (PSO) are used with this data that yield better and faster convergence to produce more accurate results. Protein secondary structures are predicted reliably, more efficiently and more accurately using FLOPRED. These techniques yield superior classification of secondary structure elements, with a training accuracy ranging between 83 % and 87 % over a widerange of hidden neurons and a cross-validated testing accuracy ranging between 81 % and 84 % and a segment overlap (SOV) score of 78 % that are obtained with different sets of proteins. These results are comparable to other recently published studies, but are obtained with greater efficiencies, in terms of time and cost.


Subject(s)
Algorithms , Computational Biology/methods , Protein Structure, Secondary , Proteins/chemistry , Amino Acid Sequence , Confidence Intervals , Databases, Protein , Models, Molecular , Molecular Sequence Data
12.
J Toxicol Sci ; 37(1): 13-21, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22293408

ABSTRACT

A series of 22 stilbene derivatives based on resveratrol were synthesized incorporating acetoxy-, benzyloxy-, carboxy-, chloro-, hydroxy- and methoxy functional groups. We examined the cytotoxicity of these 22 stilbenes in human K562 chronic myelogenous leukemia cells. Only four compounds were cytotoxic namely 4'-hydroxy-3-methoxystilbene (15), 3'-acetoxy-4-chlorostilbene (19), 4'-hydroxy-3,5-dimethoxystilbene or pterostilbene (3) and 3,5-dibenzyloxy-4'-hydroxystilbene (28) with IC(50)s of 78 µM, 38 µM, 67 µM and 19.5 µM respectively. Further apoptosis assessment on the most potent compound, 28, confirmed that the cells underwent apoptosis based on phosphatidylserine externalization and loss of mitochondrial membrane potential. Importantly, we observed a concentration-dependent activation of caspase-9 as early as 2 hr with resultant caspase-3 cleavage in 28-induced apoptosis. Additionally, a structure-activity relationship (SAR) study proposed a possible mechanism of action for compound 28. Taken together, our data suggests that the pro-apoptotic effects of 28 involve the intrinsic mitochondrial pathway characterized by an early activation of caspase-9.


Subject(s)
Apoptosis/drug effects , Caspase 9/metabolism , Stilbenes/toxicity , Cell Survival/drug effects , Humans , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Membrane Potential, Mitochondrial/drug effects , Stilbenes/chemical synthesis , Structure-Activity Relationship
13.
J Environ Biol ; 32(3): 333-7, 2011 May.
Article in English | MEDLINE | ID: mdl-22167946

ABSTRACT

Seasonal changes in soil respiration (SR), soil temperature (ST) and soil moisture (SM) were compared between a barren land with no vegetation (control) and grassland dominated by Heteropogon contortus (L.) of a semi-arid eco-system during 2005-2006. A statistically significant (p<0.001) seasonal change in SR was observed between the two sites. The variation characteristics of soil CO2 effiux rates were observed during wet periods along precipitation gradients and it was consistently higher in grasslands than in control.A maximum soil CO2 efflux of 13.35 +/- 0.33 micromol m2 s-1 in grassland and 7.33 +/- 0.8 micromol m2 s- in control was observed during rainy season-ll, i.e., from October to December, a minimum of 1.27 +/- 0.2 micromol m-2 s-1 in grassland and 0.67 +/- 0.5 micromol m-2 s-1 in control during summer season, i.e., from March to June. A positive significant relation observed between soil respiration and soil moisture (r2above 0.8) and no significant relation was observed between soil CO2 efflux and soil temperature (r2 below 0.3). In water-limited semi-arid ecosystem, rewetting of the soil due to precipitation events triggered the increased pulses of soil respiration especially in grassland when compared to the barren land. The observed soil respiration rates during summer and after the subsequent precipitation events strongly indicated that the soil water-deficit conditions reduce the efflux both in barren land (control) and in grassland of semi-arid eco-system.


Subject(s)
Carbon Dioxide/chemistry , Ecosystem , Poaceae/physiology , Soil/chemistry , Oxygen Consumption , Seasons , Temperature , Water
14.
J Environ Biol ; 32(2): 173-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21882651

ABSTRACT

Diurnal trends in net photosynthesis rate (P(N)), stomatal conductance (g(s)), water use efficiency (WUE) and biomass were compared in six-month-old seedlings of Albizia lebbeck and Cassia siamea, under different levels of drought stress. The potted plants were subjected to four varying drought treatment by withholding watering for 7 (D1), 14(D2) and 25 (D3) days. The fourth group (C) was watered daily and treated as unstressed (control). Species differed significantly (p < 0.001) in their physiological performance under varying stress conditions. Higher P(N) of 11.6 +/- 0.05 in control followed by 4.35 +/- 0.4 in D1 and 2.83 +/- 0.18 micromol m(-2) s(-1) in D2 was observed in A. lebbeck. A significant (p < 0.001) reduction in P(N) was observed in C. siamea (C 7.65 +/- 0.5 micromol m(-2) s(-1), D1, 2.56 +/- 0.33 micromol m(-2) s(-1) and D2, 1.4 +/- 0.01 micromol m(-2) s(-1)) at 9 hr. A positive correlation was seen between P(N) and g(s) (A. lebbeck, r2 = 0.84; C. siamea, r2 = 0.82). Higher WUE was observed in C. siamea (D2, 7.1 +/- 0.18 micromol m(-2) s(-1); D3, 8.39 +/- 0.11 micromol m(-2) s(-1)) than A. lebbeck, (control, 7.58 +/- 0.3 micromol m(-2) s(-1) and D3, 8.12 +/- 0.15 micromol m(-2) s(-1)). The chlorophyll and relative water content (RWC) was more in A. lebbeck than C. siamea. Maximum biomass was produced by A. lebbeckthan C. siamea. From the study, one could conclude that A. lebbeckis better than C. siamea in adopting suitable resource management strategy and be best suited for the plantation programs in the semi-arid dry lands.


Subject(s)
Albizzia/growth & development , Biomass , Cassia/growth & development , Droughts , Plant Leaves/growth & development , Albizzia/metabolism , Albizzia/physiology , Cassia/metabolism , Cassia/physiology , Chlorophyll/metabolism , Circadian Rhythm , Photosynthesis , Plant Leaves/metabolism
15.
J Postgrad Med ; 53(2): 87-90, 90A-91A, 2007.
Article in English | MEDLINE | ID: mdl-17495372

ABSTRACT

BACKGROUND: Workplace bullying is an important and serious issue in a healthcare setting because of its potential impact on the welfare of care-providers as well as the consumers. AIMS: To gauge the extent of bullying among the medical community in India; as a subsidiary objective, to assess the personality trait of the bullying victims. SETTINGS AND DESIGN: A cross-sectional, anonymous, self-reported questionnaire survey was undertaken among a convenient sample of all the trainee doctors at a Government Medical College in Tamil Nadu, India. MATERIALS AND METHODS: A questionnaire, in English with standard written explanation of bullying was used. Basic information like age, sex, job grade and the specialty in case of Postgraduates (PGs) were also collected. STATISTICAL ANALYSIS: The results were subjected to descriptive statistical analysis and Chi-square test for comparison of frequencies. RESULTS: A total of 174 doctors (115 PGs and 59 junior doctors), took part in the study with a cent percent response. Nearly half of the surveyed population reported being subjected to bullying. Nearly 54 (53%) of the men and 35 (48%) of women were subjected to bullying. Significant proportions (P < 0.0001) of medical personnel and paramedical staff bullied the PGs and junior doctors, respectively. More than 85 (90%) of bullying incidents went unreported. A significant (P < 0.0001) percentage of PGs and junior doctors revealed a personality trait towards bully. CONCLUSIONS: Workplace bullying is common among trainee doctors and usually goes unreported.


Subject(s)
Aggression , Interprofessional Relations , Medical Staff, Hospital/psychology , Stress, Psychological , Adult , Data Collection , Female , Humans , India , Male , Middle Aged
17.
Biochim Biophys Acta ; 760(2): 197-205, 1983 Oct 18.
Article in English | MEDLINE | ID: mdl-6626571

ABSTRACT

Age-related changes in renal function have been attributed to alterations in the chemical composition of the kidney tissues. Hence, the glycosaminoglycan composition of the renal cortex and medulla at varying age intervals was investigated. Glycosaminoglycans were isolated from the tissues by means of digestion with collagenase and pronase and purified by ethanol precipitation. Subsequent separation of various polyanions was accomplished by ion exchange chromatography on a Dowex 1-X2 column, using sodium chloride buffers of increasing ionic strengths. The glycosaminoglycans in each fraction were identified and quantitated by digestion with specific enzymes, including hyaluronidase, chondroitinase AC and ABC. The enzyme resistant material was separated and further digested with nitrous acid to quantitate the proportion of heparon sulfate. The results indicate that the glycosaminoglycan content of the renal medulla was much higher than the cortex at all the age intervals studied, and age-induced reduction was mainly cortical. There was a significant reduction in the heparan sulfate content of the cortex in aging. Interestingly, the major glycosaminoglycan content of the medulla was hyaluronic acid, which showed a sharp increase during aging, whereas heparan sulfate declined. Chondroitin sulfate was not altered due to age in either tissue. The molecular weight of hyaluronic acid was determined by column chromatography. Results indicate that the size of hyaluronate in the cortex was small and did not vary with age. In the medulla of the younger age group, a considerable amount of large size hyaluronate was observed. As age increased, the size decreased. The results strongly suggest that alteration in the renal glycosaminoglycans may be partly responsible for the age related protinuria and ionic imbalance.


Subject(s)
Glycosaminoglycans/metabolism , Kidney Cortex/metabolism , Kidney Medulla/growth & development , Aging , Animals , Chromatography, Gel/methods , Dogs , Glycosaminoglycans/isolation & purification , Hyaluronic Acid/analysis , Kidney Medulla/metabolism
18.
Biochim Biophys Acta ; 755(2): 237-43, 1983 Jan 25.
Article in English | MEDLINE | ID: mdl-6600934

ABSTRACT

The effect of streptozotocin-induced diabetes on the glycosaminoglycan composition of rat renal cortical tissue was evaluated. Glycosaminoglycans were isolated and purified from the kidney cortex of control and diabetic rats by means of digestion with collagenase, pronase and ethanol precipitation. Subsequent fractionation was performed by ion exchange chromatography on Dowex 1-X2 Cl using various concentrations of sodium chloride solution. The glycosaminoglycan in each fraction was characterized by digestion with hyaluronidase, chondroitinase AC and ABC. The undigested glycosaminoglycans were separated after each enzyme digestion and quantitated. The glycosaminoglycan composition of each fraction was computed from the enzyme digestion profile. The results indicate that in renal cortex of streptozotocin induced diabetic rats there was a significant reduction in the levels of dermatan sulfate, heparan sulfate and hyaluronic acid, while the chondroitin sulfate remained unaffected. In light of this finding, the significance of these anionic polysaccharides in renal functions is discussed.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Glycosaminoglycans/metabolism , Kidney Cortex/metabolism , Animals , Chondroitin Lyases , Glycosaminoglycans/isolation & purification , Hyaluronoglucosaminidase , Male , Rats , Rats, Inbred Lew
20.
J Biol Chem ; 250(20): 8111-8, 1975 Oct 25.
Article in English | MEDLINE | ID: mdl-1176464

ABSTRACT

Using galactose oxidase as well as beta-galactosidase to produce modifications of the galactose units, the functional significance of these carbohydrate residues on the coagulant activity of bovine Factor V glycoprotein was evaluated. Incubation of native Factor V with galactose oxidase or hydrolysis of asialo-Factor V with beta-galactosidase results in a loss of Factor V activity. The inactivation of Factor V by oxidation of galactose moieties is partially reversible upon reduction of the newly formed aldehyde groups with sodium borohydride. The extent of reversal depends upon the degree of inactivation achieved. Thus, Factor V which retained 30% of the original activity following galactose oxidation returns to 75% of the original coagulant activity upon borohydride reduction; but, after destruction of 85% of the original activity treatment with borohydride returns to about 30%. In the initial stages of the inactivation of Factor V by treatment with galactose oxidase, the loss of Factor V coagulant activity is directly proportional to the moles of galactose oxidized. However, as the reaction progresses, the rate of galactose oxidation exceeds the rate of loss of Factor V activity. Moreover, galactose oxidation continues even after complete inactivation of Factor V. These results suggest that the galactose residues most susceptible to attack by galactose oxidase are those necessary for the activity of this coagulant protein. Only 15 galactose residues/mol of Factor V are susceptible to galactose oxidase prior to removal of sialic acid. In contrast, 37 galactose residues/mol of Factor V are found after acid hydrolysis. These results suggest that Factor V glycoprotein contains more than one type of sialyl-galactose linkages, the C2,3 or C2,4 linkages susceptible to oxidation in the native protein and the C2,6 linkage which is resistant. Native Factor V binds with diarachidonyl lecithin forming an active complex of lower buoyant density, while the Factor V oxidized with galactose oxidase does not. The Factor V-phospholipid complex is protected from inactivation by galactose oxidase. Moreover, lipid binding diminishes the extent of oxidation of galactose residues. Certain galactose groups are essential for coagulant activity probably because they are required for binding to phospholipid, a prerequisite to Factor V action.


Subject(s)
Factor V/analysis , Galactose/analysis , Animals , Cattle , Factor V/isolation & purification , Factor V/metabolism , Galactose Oxidase/metabolism , Galactosidases , Kinetics , Phospholipids/pharmacology , Temperature
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