Role of Diffusion Tensor Imaging in Early Diagnosis and Characterization of Movement Disorders

BACKGROUND

Symptoms of movement disorders in early stages are similar, which makes definite diagnosis difficult. Hence this study was conducted to explore the role of diffusion tensor imaging (DTI) in enhancing the early diagnosis and characterization of movement disorders.

METHODOLOGY

A cross-sectional study was conducted including 60 subjects. All of them were reviewed using conventional magnetic resonance imaging (MRI) and movement disorder DTI protocol. Commercially available software was used to produce fractional anisotropy (FA) maps. Post-processing 3D reconstruction was done to obtain tractograms. Both single and multiple regions of interest (ROIs) were selected for tractography in the pons, midbrain, substantia nigra (SN) and cerebellum. MRI and DTI images were interpreted and correlated with confirmatory diagnosis.

RESULTS

According to DTI diagnosis, out of the 30 cases, 28 had movement disorders. Among cases, 36.67% had Parkinson's disease (PD), 23.33% had progressive supranuclear palsy (PSP), 16.67% had essential tremor, 13.33% had multi-system atrophy (MSA) C, and 3.33% had MSA P. DTI correctly classified all cases with PD and PSP. All cases with long disease duration and 88.24% of cases with short disease duration were also correctly classified. A statistically significant difference was observed in the proportion of diagnosis between DTI and conventional MRI.

CONCLUSION

DTI has high sensitivity and specificity for the diagnosis of movement disorders. It is capable of early diagnosis of movement disorders and also differentiating and subcategorizing them.

Graph theoretical way of understanding protein-protein interaction in ovarian cancer

Cancer is a major research area in the medical field. Precise assessment of non-similar cancer types holds great significance in according to better treatment and reducing the risk of destructiveness in patients’ health. Cancer comprises a ambient that differs in response to therapy, signaling mechanisms, cytology and physiology. Netting theory and graph theory jointly gives a viable way to probe the proteomic specific data of cancer types such as ovarian, colon, breast, oral, cervical, prostate, and lung. We observe that the P2P(protein-protein) interaction Nettings of the cancerous tissues blended with the seven cancers and normal have same structural attributes. But some of these point to desultory changes from the disease Nettings to normal implying the variation in the dealings and bring out the redoing in the complicacy of various cancers. The Netting-based approach has a pertinent role in precision oncology. Cancer can be better dealt with through mutated pathways or Nettings in preference to individual mutations and that the utility value of repositioned drugs can be understood from disease modules in molecular Nettings. In this paper, we demonstrate how the graph theory and neural Nettings act as vital tools for understanding cancer and other types such as ovarian cancer at the zeroth level.

Morphology and morphometric study of dry scapula, with emphasis on the glenoid fossa and acromion process in Chennai city, South India

Background: The morphology and morphometry of the scapula and its glenoid fossa and acromion process play a significant role in the mechanics of shoulder joint. A variable morphology is found in glenoid fossa that has clinical implications. Aims and Objectives: The aim of the study was to evaluate the morphology and morphometry of dry scapula with emphasis on glenoid fossa and acromion process. Materials and Methods: A cross-sectional study was conducted at the department of anatomy, for a period of 6 months from January 2021 to June 2021. A total of 100 unpaired dry scapula were included in the study. The morphology and dimensions were measured. The dimensions were summarized as mean and standard deviation. Statistical analysis was done Chi-square test and student’s t-test based on the variable types. Results: Out of 100 scapulae studied, 48 were right sided and 52 were left sided. The mean of maximum length of the right scapula was 149.58±10.33 mm and the left side was 148.63±10.33 mm. Among the glenoid cavities, 54 were inverted comma shaped, 30 were pear shaped, and 16 were oval shaped. In one right-sided scapula Bony Spur Extends from Base of coracoid process to supra Scapular Notch. Conclusion: Size and shape of the glenoid cavity are directly related to the dislocation of shoulder joint and may affect the results of total shoulder arthroplasty and rotator cuff surgeries. The present study analyzed the morphological types and diameters of the glenoid cavity in adult scapulae to improve the efficacy and minimize the failure rates in shoulder arthroplasty particularly those involving the glenoid component of the shoulder joint.

Correlation of biofilm production with antibiotic susceptibility pattern of Pseudomonas aeruginosa from various clinical specimens

Background: Pseudomonas aeruginosa is one of the most prevalent nosocomial pathogens that cause a life-threatening infection. One of the important characteristics of P. aeruginosa is biofilm formation which leads to antibiotic resistance. Aims and Objectives: The aim of the study was to study the antibiotic resistance pattern of P. aeruginosa isolates and correlation with their biofilm-production. Materials and Methods: A total of 87 P. aeruginosa isolates from different clinical specimens were processed and confirmed by conventional microbiological methods as per standard methodology. Antibiotic sensitivity testing was done for all isolates. Biofilm producing isolates were identified by the microtiter plate method (MTPM). Results: Of 87 P. aeruginosa isolates, majority were from pus 33 (38%), followed by urine 26 (30%), sputum 19 (22%), body fluids 7 (8%), and blood 2 (2%). Biofilm producing isolates showed more resistance in comparison to non-biofilm producers. The observed difference between biofilm formation for multidrug resistant and susceptible isolates was found to be statistically significant. Conclusion: MTPM method was an effective test for detection of biofilm formation and was also able to verify biofilm production by P. aeruginosa. This indicated a higher propensity among the clinical isolates of P. aeruginosa to form biofilm and revealed a positive correlation between biofilm formation and antibiotic resistance. This indicates the need for testing of even susceptible isolates for virulence factors such as biofilm production.

Simplified chemical processed Cd1-xAlxS thin films for high-performance photodetector applications

In this present investigation, we report the effect of aluminum (Al) doping on the photoelectric performance of cadmium sulfide (CdS) thin films prepared by cost-effective automatic nebulizer spray method. The doping of Al concentrations varied from 1 at.% to 9 at.% in the steps of 3 at.%. X-ray diffraction (XRD) patterns show hexagonal crystal structure with polycrystalline nature and the enrichment of crystallite sizes as a function of Al doping concentrations. The formed impurity phase i.e. CdO might be helpful in enhancing the photoelectric performance by its additional photo-generated charge carriers. The optical studies confirm the maximum absorption showed in the visible spectral range with the corresponding minimum bandgap of 2.28 eV for 6 at.% of Al. The room temperature photoluminescence studies show an increase of near-band-edge (NBE) emission as a function of Al doping concentration and this NBE is close to the obtained bandgap in terms of wavelength. In addition, the observed red emission at 635 nm is due to the surface-related impurities or native defect states. From the present work, the observed responsivity (R), external quantum efficiency (EQE) and detectivity (D*) of the CdS:Al detectors are 8.64 AW^-1, ∼2018% and 9.29 × 10¹¹jones, respectively for the optimum 6 at.% of CdS:Al film. The performance of CdS:Al films reported in this work are significantly improved when compared with literature reports. The present investigation, therefore offers a potential material, CdS:Al, as a photodetector for various scientific and industrial applications.

Comparison of Jet Injection Technique with Conventional Injection Technique in Patients Undergoing Endodontic Therapy

Background:

In order to reduce the fear and anxiety of injection during root canal procedures, Madajet injection technique was substituted for the first time among the adult patients to obtain its efficacy and to overcome the painful procedure during the conventional syringe technique.

Aim:

The aim of this study is to compare the clinical efficacy and level of patient acceptance of jet injections with conventional syringe technique in patients with symptomatic pulpitis.

Methodology:

Seventy patients were randomly divided into needleless pressure injection technique using Madajet XL and conventional syringe technique. The onset of anesthesia was evaluated using the electric pulp tester, and the pain was assessed using the Visual Analog Scale scoring criteria.

Statistical Analysis:

The obtained data were tabulated and subjected to the statistical analysis using the Chi-square test.

Results:

Needleless pressure injection technique (Madajet XL) proves to be effective in patients with symptomatic irreversible pulpitis during endodontic procedure.

Conclusion:

It can be concluded that the needle-less pressure injection technique (Madajet XL) promises to be a viable mode of pain control during endodontic procedures as it converts the solution to a tiny droplet which is then carried by the myelin sheath.

Influence of Carrier Gas Pressure on the Physical Properties of CdO Thin Films

Conducting cadmium oxide (CdO) thin film samples were deposited on amorphous glass substrates at the optimized substrate temperature (200 °C) as a function of carrier gas pressure (10.8, 12.7, 14.7, 16.7 and 18.6 × 104 N m−2 respectively) by spray pyrolysis technique using nebulizer. XRD results showed that all the CdO thin films were polycrystalline in nature along with cubic structure. The scanning electron microscopy (SEM) images revealed that all the thin films had a sphere like grains without any cracks. The elemental composition of the film is analyzed with EDAX spectrum formed in stochiometric range. Direct energy gap values were found to be had decreased from 2.46 to 2.42 eV as the function of carrier gas pressure had increased from 10.8 to 14.7 × 104 (N m−2) and the energy gap increased further. All the as deposited samples of Cd–O vibration bond (690 cm−1) were confirmed by FTIR spectrum. PL emission spectra revealed that all the CdO thin films exhibit a strong emission (green) peak at 520 nm. High carrier concentration (2.88 × 1019 cm−3), low resistivity (4.76 × 10−3 Ω cm) and high figure of merit (25.0 × 10−3) were observed for 14.7 × 104 (N m−2) carrier gas pressure of CdO thin film.

Separation of americium (III) and strontium (II) using TEHDGA and 18-crown-6

This work describes extraction of Am(III) and Sr(II) together with tetra(2-ethylhexyl) diglycolamide (TEHDGA) and selective back-extraction of strontium with a strontium complexant, 18-crown-6, leading to their separation from each other. 0.3 M TEHDGA+5% isodecyl alcohol/n-dodecane was used to extract Am(III) and Sr(II) from 4 M nitric acid into organic phase with very high D (D Am=1000, D Sr=22) and 0.1 M 18-crown-6 dissolved in 4 M nitric acid is used for selective stripping of Sr(II) from loaded extract phase. Am(III) left in the extract phase was then stripped with 0.01 M nitric acid. Stripping of Sr(II) was found to increase with increase in 18-crown-6 concentration, at 0.1 M 18-crown-6 dissolved in 4 M nitric acid, 83% of the loaded strontium (D Sr=0.20) was back-extracted in a single contact while loss of Am(III) was 0.8% (D Am=122.45). Stoichiometry limit of 1:1 was observed between strontium and 18-crown-6. Strontium was precipitated and separated from the complexant by Na2SO4 or Na2CO3. This process was tested with simulated solution of high level waste and found suitable for quantitative recovery of strontium with high purity.

Quantitative Profile Analysis of Mulberry Silkworm <i>Bombyx mori </i>L. (CSR₂XCSR₄)

Bombyx mori. L. (CSR2XCSR4) is a bivolitne crossbreed that produces high quantity of silk. The weights of worms and glands are directly related to the yield of silk, higher larval weights leads to higher silk production. In the present study, quantitative parameters of 5th instar and pupal stages of silkworm larvae were observed. The analysis of quantitative estimation showed that the maximum weights and lengths of silk gland and silk worm were recorded on 7th day of 5th instar larval stage. The day dependent variation in protein concentration was observed in total silk gland 5th instar larval and pupal stages.

Quantitative Profile Analysis of Mulberry Silkworm <i>Bombyx mori </i>L. (CSR₂XCSR₄)

Bombyx mori. L. (CSR2XCSR4) is a bivolitne crossbreed that produces high quantity of silk. The weights of worms and glands are directly related to the yield of silk, higher larval weights leads to higher silk production. In the present study, quantitative parameters of 5th instar and pupal stages of silkworm larvae were observed. The analysis of quantitative estimation showed that the maximum weights and lengths of silk gland and silk worm were recorded on 7th day of 5th instar larval stage. The day dependent variation in protein concentration was observed in total silk gland 5th instar larval and pupal stages.

Tretinoin Nanogel 0.025% Versus Conventional Gel 0.025% in Patients with Acne Vulgaris: A Randomized, Active Controlled, Multicentre, Parallel Group, Phase IV Clinical Trial

BACKGROUND

Conventional topical tretinoin formulation is often associated with local adverse events. Nanogel formulation of tretinoin has good physical stability and enables good penetration of tretinoin into the pilo-sebaceous glands.

AIM

The present study was conducted to assess the efficacy and safety of a nanogel formulation of tretinoin as compared to its conventional gel formulation in the treatment of acne vulgaris of the face.

MATERIALS AND METHODS

This randomized, active controlled, multicentric, phase IV clinical trial evaluated the treatment of patients with acne vulgaris of the face by the two gel formulations locally applied once daily at night for 12 wk. Acne lesion counts (inflammatory, non-inflammatory & total) and severity grading were carried out on the monthly scheduled visits along with the tolerability assessments.

RESULTS

A total of 207 patients were randomized in the study. Reductions in the total (72.9% vs. 65.0%; p = 0.03) and inflammatory (78.1% vs. 66.9%; p = 0.02) acne lesions were reported to be significantly greater with the nanogel formulation as compared to the conventional gel formulation. Local adverse events were significantly less (p = 0.04) in the nanogel group (13.3%) as compared to the conventional gel group (24.7%). Dryness was the most common adverse event reported in both the treatment groups while peeling of skin, burning sensation and photosensitivity were reported in patients using the conventional gel only.

CONCLUSION

In the treatment of acne vulgaris of the face, tretinoin nanogel formulation appears to be more effective and better tolerated than the conventional gel formulation.

Phenytoin, folic acid and gingival enlargement: Breaking myths

Background:

Epilepsy is described as a chronic neurological disorder characterized by recurrent seizures of cerebral origin, presenting with episodes of sensory, motor or autonomic phenomenon with or, without loss of consciousness. A recent meta-analysis of published and unpublished studies puts an overall prevalence rate of epilepsy in India at 5.59 per 1,000 populations. There have been studies that report clinical benefits of the use of folic acid as an adjuvant to the anti-epileptic therapy in the prevention of anti-epileptic drug induced gingival enlargement. However, studies conducted in the past have also reported precipitation of epileptic attacks in patients on folic acid adjuvant therapy due to fall in sera levels of phenytoin due to drug interactions. The study was planned to investigate the association of phenytoin induced gingival enlargement and sera levels of folic acid in epileptic patients on phenytoin therapy so as to justify the use of folic acid as a routine adjuvant to the usual anti-epileptic therapy to prevent this inevitable adverse effect without destabilizing the ongoing regimen leading to the precipitation of seizures in an otherwise stable patient (breakthrough seizures).

Materials and Methods:

A total of 100 patients between the ages 18 and 50 years were clinically diagnosed with epilepsy prior to the start of phenytoin therapy were included based on selection criteria and written informed consents were obtained. Assessment of serum folic acid levels and gingival enlargement was performed prior to the start of and after 1 year of phenytoin therapy.

Statistical Analysis Used:

The statistical analysis was carried out using t-test and the baseline serum folate levels and the serum folate levels obtained after 1 year of phenytoin therapy were correlated with the respective grades of gingival enlargement using Pearson's coefficient formula.

Results:

The results of the study confirmed a significant association between low serum folate levels with increasing severity as well as an early onset of phenytoin induced gingival enlargement.

Conclusions:

The results of the study suggest a higher incidence of gingival enlargement with an early onset and increased severity in phenytoin treated epileptic patients with a positive correlation with falling serum folic acid levels as the duration of the therapy increases.

A study on gingival enlargement and folic acid levels in phenytoin-treated epileptic patients: Testing hypotheses

Background:

There have been studies that report clinical benefits of the use of folic acid as an adjuvant to the antiepileptic therapy in the prevention of antiepileptic drug-induced gingival enlargement. However, studies in the past have also reported precipitation of epileptic attacks in patients on folic acid adjuvant therapy due to fall in sera levels of phenytoin due to drug interactions. The study was planned to investigate the association of phenytoin-induced gingival enlargement and sera levels of folic acid in epileptic patients on phenytoin therapy. The statistical analysis was done using t-test and the baseline serum folate levels and the serum folate levels obtained after 6 months of phenytoin therapy were correlated with the respective grades of gingival enlargement using Pearson's coefficient formula.

Methods:

A total of 25 patients aged between 18 and 50 years, clinically diagnosed with epilepsy prior to the start of phenytoin therapy were included based on selection criteria and written informed consents were obtained. Assessment of serum folic acid levels and gingival enlargement was done prior to the start of and after 6 months of phenytoin therapy.

Results:

The results of the study confirmed a significant association between low serum folate levels with increasing severity as well as an early onset of phenytoin-induced gingival enlargement.

Conclusions:

The results of the study suggest a higher incidence of gingival enlargement in phenytoin treated epileptic patients with a positive correlation with falling serum folic acid levels as the duration of the therapy increases.

Inflammatory Markers-Serum Level of C-Reactive Protein, Tumor Necrotic Factor-α, and Interleukin-6 as Predictors of Outcome for Peripartum Cardiomyopathy

AIM/OBJECTIVE

Peripartum cardiomyopathy (PPCM) is a disorder of unknown etiology in which symptoms of heart failure occur between the last month of pregnancy and 5 months post-partum. These findings prompted us to carry out a more detailed study aimed at correlating plasma levels of C-reactive protein TNF-α and IL-6 as prognostic value for major clinical in-hospital events and 6-month follow-up in patients with PPCM.

MATERIALS AND METHODS

After ethical clearance, in the present prospective case-control study, a total of 86 subjects were enrolled [patients (n = 46) and controls (n = 40)]. After checking for the inclusion and exclusion criteria, informed consent was obtained and patients were enrolled. The details of history of pre-eclampsia and mode of delivery were obtained from the patients. The history of onset of symptoms and signs was recorded at the first presentation and at 6 months. Clinical assessment, echocardiography, and blood analysis were done at baseline and after 6 months of standard therapy. All patients received treatment with diuretics and the ACE inhibitor (ramipril), Carvedilol if not contraindicated, and inotropic support inj-Dobutamine. Inflammatory markers (C-reactive protein, TNF-α, and IL-6) were measured at baseline and at 6 months. Data were analyzed using the SAS version 9.1 statistical program.

RESULTS

The characteristics of the study population at first presentation to the cardiac clinic are similar (compared with controls): 0.91 % of the study patients were diagnosed as PPCM patients for the first time and 49 % patients presented within one month after delivery. C-reactive protein (22 vs 08 mg/dl, p < 0.05), TNF-α (9.6 vs 3.2 pg/dl, p < 001), and IL-6 (73.19 ± 34.4 vs 31.52 ± 8.83 pg/dl, p < 0.005) were significantly abnormal, and these patients showed significantly higher LV dimensions, LV EDD (61.6 ± 7.1 vs 46 ± 9 mm p < 0.004) LV ESD (53.1 ± 7 vs 32 ± 8, p < 0.005), and significantly lower echocardiographic left ventricular ejection fraction (LVEF) (25.9 ± 8.2 vs 55 ± 12 p < 0.001) and correlate well with NYHA FC and death. LVEF improved from 25.9 ± 8.2 to 42.9 + 13.6 % at 6 months (p < 0.0001). Patients who completed 6 months of standard care showed a significant reduction of heart rate, LV dimensions, and NYHA FC (p < 0.001). However, normalization of LVEF (>50 %) was only observed in 11 (35 %) patients. Seven patients died within 6 months of diagnoses and eight patients were lost to follow-up.

CONCLUSIONS

Plasma markers of inflammation were significantly elevated in PPCM patients and correlated with increased LV dimensions and lower EF at presentation. Baseline CRP, IL-6, TNF-α, and higher NYHA FC were the only predictors of mortality. These results contribute to inflammation which may contribute to the pathogenesis of PPCM and its complications and predictors of mortality.

Increased neuronal survival in the brainstem during liver injury: role of γ-aminobutyric acid and serotonin chitosan nanoparticles

γ-Aminobutyric acid (GABA)- and serotonin (5-HT)-mediated cell signaling, neuronal survival enhancement, and reduced neuronal death in brainstem during liver injury followed by active liver regeneration have a critical role in maintaining routine bodily functions. In the present study, GABAB and 5-HT2A receptor functional regulation, interrelated actions of neuronal survival factors, and expression of apoptotic factors in the brainstem during GABA and 5-HT chitosan nanoparticles-induced active liver regeneration in partially hepatectomized rats were evaluated. Partially hepatectomized rats were treated with the nanoparticles, and receptor assays and confocal microscopic studies of GABAB and 5-HT2A receptors, gene expression studies of GABAB and 5-HT2A receptors, nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), Akt-1, phospholipase C, Bax, and caspase-8 were performed with the brainstems of experimental animals. A significant decrease in GABAB and 5-HT2A receptor numbers and gene expressions denoted a homeostatic adjustment by the brain to trigger the sympathetic innervations during elevated DNA synthesis in the liver. The neuronal apoptosis resulting from the loss of liver function after partial hepatectomy was minimized by nanoparticle treatment in rats compared with rats with no treatment during regeneration. This was confirmed from the gene expression patterns of NF-κB, TNF-α, Akt-1, phospholipase C, Bax, and caspase-8. The present study revealed the potential of GABA and 5-HT chitosan nanoparticles for increasing neuronal survival in the brainstem during liver injury following regeneration, which avoids many neuropsychiatric problems.

A case of acute pancreatitis with occupational exposure to organophosphorus compound

Pesticides have contributed to dramatic increase in the quality and quantity in crop yields. Organophosphates are commonly used as insecticides in agriculture and are potent toxicants. Patients with organophosphorus poisoning may present with subclinical features of acute pancreatitis. Proper biochemical investigation and clinical correlation helps in diagnosis.

Serum total protein, albumin and advanced oxidation protein products (AOPP)--implications in oral squamous cell carcinoma

BACKGROUND

The role of oxygen free radicals in the initiation, promotion and progression of carcinogenesis and the protective role of anti-oxidant defenses have been the subject of much speculation in the recent past with conflicting reports in the literature.

OBJECTIVES

The aim of this study was to measure the concentration/levels of serum total proteins, albumin and advanced oxidation protein products as markers of oxidative stress in sera of patients with an oral pre-cancerous lesion and frank oral cancer.

MATERIALS AND METHODS

The study consisted of sera analysis of 30 new patients of histologically proven well-differentiated, oral squamous cell carcinoma and 10 patients, clinically diagnosed with a potentially malignant epithelial lesion, speckled leukoplakia, aged between 40 to 60 years, in addition to 25 healthy controls. One way analyses of variance were used to test the difference between groups. The normality of data was checked before the statistical analysis was performed.

RESULTS

The study revealed variations in sera levels of albumin and advanced oxidation protein products to be statistically significant (p<0.001).

CONCLUSION

The results obtained emphasize the need for more studies with larger sample sizes to be conducted before a conclusive role could be drawn in favour of sera levels of total protein, albumin and advanced oxidation protein products as markers of diagnostic significance and of the transition from the various oral pre-cancerous lesions and conditions into frank oral cancers.

Targeting glutamate mediated excitotoxicity in Huntington's disease: neural progenitors and partial glutamate antagonist--memantine

Huntington's disease (HD) is a fatal progressive neurodegenerative disorder with autosomal dominant inheritance. In humans mutated huntingtin (htt) induces a preferential loss of medium spiny neurons (MSN) of the striatum and causes motor, cognitive and emotional deficits. One of the proposed cellular mechanism underlying medium spiny neurons degeneration is excitotoxic pathways mediated by glutamate receptors. The hypothesis proposed is restoration of medium spiny neurons in Huntington's disease using neural progenitor cell implantation and attenuation of glutamate mediated excitotoxicity using a partial glutamate antagonist - Memantine. Memantine can block the NMDA receptors and will prevent excess calcium influx into the neurons decreases the vulnerability of medium spiny neurons to glutamate mediated excitotoxicity. Neural progenitor cell implantation can enhance endogenous neurogenesis process replacing the degenerated medium spiny neurons in the striatum. This has immense significance in the management of Huntington's disease.

Advanced oxidation protein products and total antioxidant activity in colorectal carcinoma

The present study was designed to assess the levels of advanced oxidation protein products (AOPP) and percent hemolysis (that indirectly indicates the degree of membrane damage secondary to lipid peroxidation) in colorectal carcinoma. Glutathione (GSH), total thiols and albumin were measured to determine the antioxidant status. Considering the dynamic interaction between various antioxidants in the body, we measured the total antioxidant activity (AOA). Globulin was measured to assess the inflammatory response secondary to oxidative stress. Investigations were conducted in 45 cases of recently diagnosed primary colorectal adenocarcinoma. As control, 45 age and sex matched healthy persons were chosen. GSH was estimated in whole blood, percent hemolysis in RBC suspension and other parameters in plasma. We observed a very high significant increase (P<0.001) in AOPP, percent hemolysis and a highly significant increase (P<0.01) in globulin in colorectal carcinoma. We observed a very high significant decrease (P<0.001) in whole blood GSH, total thiols, albumin, AOA and a significant decrease (P<0.05) in plasma GSH in colorectal carcinoma. A very high significant negative correlation between percent hemolysis and AOA and an apparent negative correlation between total thiols and AOPP was seen in colorectal carcinoma. This demonstrated oxidative stress, decreased antioxidant status and secondary inflammatory response in colorectal carcinoma.

Glial cell line-derived neurotrophic factor increases beta-cell mass and improves glucose tolerance

BACKGROUND & AIMS

Pancreatic beta-cell mass increases in response to increased demand for insulin, but the factors involved are largely unknown. Glial cell line-derived neurotrophic factor (GDNF) is a growth factor that plays a role in the development and survival of the enteric nervous system. We investigated the role of GDNF in regulating beta-cell survival.

METHODS

Studies were performed using the beta-TC-6 pancreatic beta-cell line, isolated mouse pancreatic beta cells, and in vivo in transgenic mice that overexpress GDNF in pancreatic glia. GDNF receptor family alpha1 and c-Ret receptor expression were assessed by reverse-transcription polymerase chain reaction and immunofluorescence microscopy. Apoptosis was evaluated by assessing caspase-3 cleavage. Phosphoinositol-3-kinase signaling pathway was analyzed by Akt phosphorylation. Glucose homeostasis was assessed by performing intraperitoneal glucose tolerance tests. Insulin sensitivity was assessed using intraperitoneal injection of insulin.

RESULTS

We demonstrate the presence of receptors for GDNF, GFRalpha1, and c-Ret on beta cells. GDNF promoted beta-cell survival and proliferation and protected them from thapsigargin-induced apoptosis (P<.0001) in vitro. Exposure of beta-cells to GDNF also resulted in phosphorylation of Akt and GSK3beta. Transgenic mice that overexpress GDNF in glia exhibit increased beta-cell mass, proliferation, and insulin content. No differences in insulin sensitivity and c-peptide levels were noted. Compared with wild-type mice, GDNF-transgenic mice have significantly lower blood glucose levels and improved glucose tolerance (P<.01). GDNF-transgenic mice are resistant to streptozotocin-induced beta-cell loss (P<.001) and subsequent hyperglycemia.

CONCLUSIONS

We demonstrate that over expression of GDNF in pancreatic glia improves glucose tolerance and that GDNF may be a therapeutic target for improving beta-cell mass.

Glial cell line-derived neurotrophic factor-mediated enteric neuronal survival involves glycogen synthase kinase-3beta phosphorylation and coupling with 14-3-3

Glial cell line-derived neurotrophic factor (GDNF) promotes the growth and survival of enteric neurons, but the mechanisms involved are poorly understood. GDNF is known to promote the survival of enteric neurons through activation of the PI3-Kinase/Akt signaling pathway. We investigated the role of glycogen synthase kinase-3beta (GSK-3beta) in enteric neuronal survival, and the ability of GDNF to regulate the activity of GSK-3beta using primary rat embryonic enteric neurons. GDNF, through activation of the PI3-kinase pathway enhanced the phosphorylation of GSK-3beta at its N-terminal serine-9 residue, and promoted the association of GSK-3beta with 14-3-3. Transfection of a constitutively active S9A-GSK-3beta mutant prevented the survival effects of GDNF, whereas a dominant negative GSK-3beta construct prevented GDNF withdrawal-induced cell death. Increased GSK-3beta activity was associated with an increase in tau phosphorylation. Thus, GDNF promotes enteric neuronal survival by modulating GSK-3beta and its downstream target tau. Inhibitors of GSK-3beta activity may have therapeutic potential in improving enteric neuronal survival.

Studies on genomic DNA topology and stability in brain regions of Parkinson's disease

DNA damage has been postulated as a mechanism of neuronal death in Parkinson's disease (PD). In the present study, genomic DNA was isolated from eight brain regions (frontal, temporal, and occipital cortex, hippocampus, caudate/putamen, thalamus, cerebellum, and midbrain) from five neuropathologically confirmed cases of Parkinson's disease and six control brains and analyzed for the presence of single and double strand breaks, melting temperature, EtBr intercalation, DNAse digestion pattern, and DNA conformations. The results showed that DNA from midbrain in PD accumulated significantly higher number of strand breaks than age-matched controls. Caudate nucleus/putamen, thalamus, and hippocampus also showed more DNA fragmentation compared to control brains. Circular dichroism studies showed that DNA conformation was altered with imprecise base stacking in midbrain, caudate nucleus/putamen, thalamus, and hippocampus in PD. However, DNA from frontal, temporal, and occipital cortex, and cerebellum was not affected significantly in PD group as compared to controls. This study provides a comprehensive database on stability, damage, and conformations of DNA in different regions in brains of PD patients.

Dominant negative effect of novel mutations in pyruvate kinase-M2

The natural mutations observed in pyruvate kinase (PK)-M2, a homotetramer isozyme, in this study correlated with the differential activity of the enzyme in a dominant negative manner in B-lymphoblastoid cells, established from two Bloom syndrome (BS) patients, BS1 and BS3 by 50 and 90%, respectively; and by 75% in the freshly obtained PHA stimulated lymphocytes of a BS patient diagnosed for the first time in India. A gene screen involving the critical domains of the PK-M gene in BS cells resulted in the observation of a missense mutation in BS1 and the BS patient and a frame shift mutation in BS3, in exon-10, coding for the intersubunit contact domain (ISCD) of the PK-M2 protein. Apart from these mutations, other variations in this region of the gene, both in normal and BS cells, did not affect the enzyme activity, since these were silent. Computer-based modeling studies of the PK-M2 protein with each mutation was suggestive of a changed interaction between two domains within a subunit in BS1, a gross structural change in BS3, and a changed interaction between two subunits of the tetramer in the BS patient. An absence of such mutations in other regions of the PK-M2 gene in normal subjects and in the randomly chosen unrelated genes in the DNA from BS cell lines and the cells from the BS patient, authenticated the presence of the observed mutations in Bloom syndrome cells. A correlation observed between the differential enzyme activity and the nature of mutation in the intersubunit contact domain (ISCD) region of the PK-M2 gene was interesting, and indicted how the site and the nature of mutation in a heterozygous state could influence the enzyme activity differentially and in a dominant negative manner. The importance of these mutations in Bloom syndrome cells, however, remains to be elucidated, and can only be conjectured.