Diagnosis of Herpes Simplex Encephalitis by ELISA Using Antipeptide Antibodies Against Type-Common Epitopes of Glycoprotein B of Herpes Simplex Viruses.

Herpes simplex encephalitis (HSE) represents one of the most severe infectious diseases of the central nervous system (CNS). As effective antiviral drugs are available, an early, rapid, and reliable diagnosis has become important. The objective of this article was to develop a sensitive ELISA protocol for herpes simplex viruses (HSV) antigen detection and quantitation by assessing the usefulness of antipeptide antibodies against potential peptides of HSV glycoprotein B (gB). A total of 180 cerebrospinal fluid (CSF) samples of HSE and non-HSE patients were analyzed using a panel of antipeptide antibodies against synthetic peptides of HSV glycoprotein gB. The cases of confirmed and suspected HSE showed 80% and 51% positivity for antipeptide against synthetic peptide QLHDLRF and 77% and 53% positivity for antipeptide against synthetic peptide MKALYPLTT, respectively for the detection of HSV antigen in CSF. The concentration of HSV antigen was found to be higher in confirmed HSE as compared to suspected HSE group and the viral load correlated well with antigen concentration obtained using the two antipeptides in CSF of confirmed HSE group. This is the first article describing the use of antibodies obtained against synthetic peptides derived from HSV in diagnostics of HSE using patients' CSF samples.

Rapid diagnosis and simultaneous identification of tuberculous and bacterial meningitis by a newly developed duplex polymerase chain reaction.

The present study describes the development and evaluation of a duplex polymerase chain reaction (D-PCR) for diagnosis and simultaneous identification of tuberculous meningitis (TBM) and bacterial meningitis (BM) in a single reaction. A D-PCR with primers amplifying portions of the Mycobacterium tuberculosis IS6110 and the eubacteria 16SrDNA sequence in a same reaction mix was developed and tested on DNA extracted from 150 clinical CSF samples from different categories (TBM = 39, BM = 26, control infectious and non-infectious category = 85). The results indicate a clear differentiation between bands for eubacteria and M. tuberculosis with an analytical sensitivity of 10(3) cfu/ml for eubacteria and 10(2) cfu/ml for M. tuberculosis. When evaluated in clinical samples, D-PCR overall diagnosed 100 % confirmed TBM and 100 % confirmed BM cases with overall specificity of 96.5 %. D-PCR can be an effective tool for diagnosis and simultaneous identification of TBM or BM in a single PCR reaction. It saves time, cost, labour and sample amount and help in administration of appropriate antimicrobial therapy. The proposed diagnostic assay would be helpful in correct and rapid management of TBM and BM patients.

Determination of viral load by quantitative real-time PCR in herpes simplex encephalitis patients.

OBJECTIVE: Human herpesviruses cause various acute, subacute, and chronic disorders of the central nervous system and peripheral nervous systems in adults and children. The objective of the present study is to summarize the experience gained with the estimation of viral load in the central nervous system of children and adults with herpes simplex encephalitis (HSE) admitted to a neurological institute at Nagpur, India, by quantitative real-time PCR (qPCR) assay within the past 4 years. METHODS: The qPCR assay was evaluated retrospectively in 242 cerebrospinal fluid (CSF) samples from patients. Evaluation of possible relationships was done between the herpes simplex virus (HSV) DNA concentration in CSF with that of patients' clinical and laboratory manifestations. The prevalence of the type of HSV in the study population was also determined using type-specific real-time PCR analysis. RESULTS AND CONCLUSIONS: Real-time analysis using type-specific primers revealed the presence of predominantly HSV-1 genotype in the study population. The qPCR results show that in patients with higher viral loads in their CSF, a greater number of cases were associated with the presence of lesions in the brain as revealed by computed tomography/magnetic resonance imaging scan. They required acyclovir therapy for a longer duration and had a poorer clinical outcome than the patients with lower viral loads in their CSF.

Loop-mediated isothermal amplification for rapid and reliable diagnosis of tuberculous meningitis.

Diagnosis of tuberculous meningitis (TBM) is often difficult. A reliable, simple, and rapid diagnostic test that can be performed in any standard laboratory could be helpful in TBM diagnosis. In this study, a loop-mediated isothermal amplification assay (LAMP) was evaluated to rapidly detect and diagnose TBM infection and was compared to the performance of nested PCR. Six specific primers were used to recognize the IS6110 genomic sequence from Mycobacterium tuberculosis, which included one forward outer primer, one reverse outer primer, two respective inner primers, and two loop primers. The optimum reaction temperature and time were 63°C and 60 min, respectively. Nested PCR was performed targeting the IS6110 region from M. tuberculosis using a commercial kit. The LAMP method yielded a sensitivity of 88.23% and a specificity of 80%, compared to the nested-PCR assay, which yielded a sensitivity of 52.9% and a specificity of 90% for TBM diagnosis. Comparative experiments showed that the LAMP assay is a rapid, sensitive, and specific method to detect TBM infection and that it is superior to the nested-PCR assay. LAMP is very simple, and it can be performed in any laboratory and in rural settings.

Evaluation of routinely performed hematological and biochemical parameters for the prognosis of acute ischemic stroke patients.

We have investigated serial changes in routine hematological and biochemical analysis in the follow-up samples collected from acute ischemic stroke (AIS) patients (n = 17) at admission (0 h) and 24, 48, 72 and 144 h after admission, respectively, to determine their prognostic significance. Blood samples from age and sex matched healthy control subjects (n = 12) were also collected. We observed significant changes in erythrocyte sedimentation rate (ESR), white blood cell count (WBC), polymorph, lymphocyte, and total protein levels in discharged and expired AIS patients. These changes were more in expired AIS patient throughout the follow-up. Similarly low hemoglobin (Hb) and globulin were observed only in expired AIS patient. Thus ESR, WBC, polymorph, lymphocyte, and total protein may be used as a predictor for severity of AIS. Similarly low Hb and globulin in AIS patient may be used as a predictive biomarker for short-term mortality after AIS.

Effect of repeat dose of BCG vaccination on humoral response in mice model.

BCG is the only vaccine presently available against tuberculosis but it is estimated to prevent only 5% of the all potentially vaccine-preventable deaths due to Tuberculosis. Keeping these in view the present study has been undertaken to evaluate the efficacy of BCG and the effect of repeat dose of BCG on antimycobacterial humoral response in mouse model. To improve BCG immunogenicity, specific anti-mycobacterial immune responses (anti-BCG titre and total IgG level) were evaluated in mouse model using boost immunization protocols with the BCG vaccine. Mice induced with a repeat dose of BCG showed an increased anti mycobacterial humoral response, which gradually declined few weeks after single dose of BCG administration. The results suggest improved efficacy of BCG vaccine by giving repeat dose of BCG that can enhance the level of immunoprotection against tuberculosis as opposed to a single BCG dose.

Detection of viral antigen, IgM and IgG antibodies in cerebrospinal fluid of Chikungunya patients with neurological complications.

BACKGROUND: During Chikungunya virus (CHIKV) epidemic in Nagpur, India, we identified some suspected Chikungunya patients with neurological complications. Early and cost-effective diagnosis of these patients remains problematic despite many new advanced diagnostic methods. A reliable diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain definitive early diagnosis of CHIKV patients with neurological complications. In our laboratory, in-house ELISA protocol for viral antigen, immunoglobulin M (IgM) and IgG detection has been developed and assessed for the diagnosis of CHIKV patients with neurological complications. METHOD: Cerebrospinal fluid samples of forty-six patients who developed neurological symptoms within two months of CHIKV infections along with control subjects were included in the study and were analyzed for the presence of antigens and of IgM and IgG using an ELISA protocol. RESULTS: The ELISA method for antigen detection yielded 80% sensitivity and 87% specificity for the diagnosis of CHIKV patients with neurological complications. The sensitivity for detection of IgM 48% or IgG 63% was significantly lower than the antigen assay (80%). CONCLUSION: The detection of viral antigen in CSF of CHIKV patients with neurological complications by ELISA method gave a more reliable diagnosis than antibodies detection that can be used to develop an immunodiagnostic assay with increased sensitivity and specificity.

An approach towards peptide-based antibody detection for diagnosis of Chikungunya infection.

Chikungunya infection, although rarely fatal, is associated with significant morbidity which necessitates its diagnosis in the initial stages. Currently for diagnosis, together with clinical symptoms, immunological methods such as IgG/IgM detection, molecular methods such as real-time reverse transcriptase-polymerase chain reaction and viral isolation methods are available but they are either not very specific or they require high-level sophisticated infrastructures. In the present study, an enzyme-linked immunosorbent assay to evaluate antibody responses to peptides designed from the CHIKV E2 envelope glycoprotein was performed. Synthesized peptides were evaluated with confirmed Chikungunya and non-Chikungunya serum samples for antibody detection. The results demonstrate that the synthetic peptide-based diagnosis of Chikungunya can be an efficient and a more accessible approach in immunodiagnostics.

Changes in cerebrospinal fluid cytokine expression in tuberculous meningitis patients with treatment.

BACKGROUND: The prevalence of tuberculous meningitis (TBM) is very high in developing areas of the world. Inflammation and cytokine patterns produced by T lymphocytes play an important role in susceptibility to infections. The inflammatory response and production of cytokines in the cerebrospinal fluid (CSF) of patients with TBM are well documented. Conversely, little is known about the role of pro- and anti-inflammatory cytokines in the CSF of TBM patients. The goal of the present study was to estimate the level of proinflammatory cytokine and anti-inflammatory cytokine levels in CSF samples from TBM patients. MATERIALS AND METHODS: To study this, in vivo levels of IL-2 and IFN-gamma (proinflammatory cytokines), and IL-10 (anti-inflammatory cytokine) in the CSF of 60 adult TBM patients and 50 age- and sex-matched non-TBM controls were measured. These cytokines were estimated in the CSF of TBM patients before and after starting treatment. RESULTS: High levels of proinflammatory cytokines as compared to anti-inflammatory cytokines were found in TBM patients before treatment. However, CSF samples from TBM patients after treatment showed elevated levels of anti-inflammatory and low levels of proinflammatory cytokines. CONCLUSIONS: We hypothesize that an increase in anti-inflammatory cytokines during treatment may indicate a favorable response.

Assessment of immune response to repeat stimulation with BCG vaccine using in vitro PBMC model.

BACKGROUND: Tuberculosis (TB) is one of the most prevalent cause of death due to a single pathogen. Bacillus Calmette Guérin (BCG) is the only vaccine available for clinical use that protects against miliary TB; however, this vaccine has shown variable levels of efficacy against pulmonary TB. In India, a single dose of BCG vaccine is given and there are few countries where repeated doses of BCG are given. The incidence of TB in India is very high inspite of primary vaccination in neonatal period and therefore requires consideration for repeated immunization. METHODS: To improve BCG immunogenicity, we have evaluated specific antimycobacterial immune responses (anti-BCG IgG and IFN-gamma), T cell activity-ADA, CD4 and CD8 T cell count, and CD4/CD8 ratio in a peripheral blood mononuclear cells (PBMC) model using boost immunization protocols with the BCG vaccine. PBMC were induced with a repeat dose of BCG at 24 and 72 hrs of cell culture. RESULTS: At the end of the experimental time, supernatant was collected to estimate anti-BCG IgG titer, interferon gamma, ADA activity, CD 4 and CD8 T cell count, and CD4/CD8 ratio. We demonstrated that PBMC induced with a repeat dose of BCG showed an increased specific anti-mycobacterial immune responses, T cell activity, and ADA activity as compared to PBMC induced with BCG alone or without BCG induction. CONCLUSION: The repeat BCG stimulation of PBMC obtained from BCG vaccinated individuals shows enhanced immune activation with respect to increased anti-BCG titre, IFN-gamma and ADA activity without concomitant increase in CD4 and CD8 cells. This study provides some basic data in future experiments in animal models with respect to repeat BCG vaccination.

Comparative evaluation of a PCR assay with an in-house ELISA method for diagnosis of Tuberculous meningitis.

BACKGROUND: Despite the availability of many investigational methods, diagnosis of Tuberculous meningitis (TBM) is extremely difficult. Polymerase chain reaction (PCR), using specific primers for Mycobacterium tuberculosis (MTB), shows variable sensitivity and specificity. In this study, we assessed the usefulness of the PCR assay for TBM diagnosis and compared it to our in-house enzyme-linked immunosorbent assay (ELISA) based on antigen 85 complex detection. MATERIAL/METHODS: Cerebrospinal fluid (CSF) samples were obtained from 189 patients in 3 different groups: confirmed TBM (n=13), clinically suspected TBM (n=37), and non-TBM (n=139). A PCR assay was performed using a specific pair of primers designed to amplify the insertion sequence IS6110 in the MTB genome, and it was compared to ELISA, using monoclonal antibodies against the purified Ag 85 complex, to analyze CSF samples and diagnose TBM. RESULTS: The PCR assay yielded sensitivity and specificity values of 80% and 84%, which are slightly less, but comfortable to the values obtained for the ELISA method (84% and 91%). Interestingly, a combinatorial approach using both methods provided sensitivity and specificity of 88% and 93%. CONCLUSIONS: The PCR assay was found to be as sensitive and specific as the well-established in-house ELISA technique, suggesting that it can be used for TBM diagnosis.

Evaluation of the inflammatory response in sera from acute ischemic stroke patients by measurement of IL-2 and IL-10.

OBJECTIVES: We compared the concentrations of the proinflammatory cytokine interleukin-2 (IL-2) with the anti-inflammatory cytokine interleukin-10 (IL-10) in serial serum samples from improved and expired acute ischemic stroke (AIS) patients to determine their prognostic usefulness. MATERIALS AND METHODS: Blood from AIS patients (n = 17) admitted within 24 h of the onset of symptoms were collected at admission and 24, 48, 72, and 144 h after admission. Pro- and anti-inflammatory cytokines were measured by enzyme-linked immunosorbant assay. RESULTS: IL-2 levels were elevated in serum samples from AIS patients collected at 0 (0.97, P < 0.01) and 24 h (1.011, P < 0.01). IL-2 concentrations gradually decreased at subsequent time-points (48, 72, and 144 h samples, 0.324, P < 0.05) in patients who improved (n = 13), but not in those who expired (n = 4). Similarly, a decrease in IL-10 levels was observed in serum samples from AIS patients who improved at 24 h (0.180, P < 0.05), followed by significant increases at 72 h (0.97, P < 0.01 vs. control) and 144 h (1.38, P < 0.01). CONCLUSION: The levels of IL-2 and IL-10 correlate well with outcome in AIS patients and may be useful in prognosis.

Neurological complications of Chikungunya virus infection.

BACKGROUND: In May 2006, there was a large Chikungunya virus infection (CHIKV) outbreak in the Nagpur district of Maharashtra, a province in western India. Usually, CHIKV is a self-limiting febrile illness. However, neurological complications have been described infrequently. AIM: To study the clinical characteristics of various neurological complications associated with CHIKV infections. MATERIALS AND METHODS: Patients with neurological complications following CHIKV infection during the outbreak were the subjects of the study. On the basis of clinical features and investigative findings, patients were grouped into various neurological syndromes: Encephalitis, myelopathy, peripheral neuropathy, myeloneuropathy, and myopathy. Cerebrospinal fluid (CSF) samples were also collected for biochemical and serological studies. RESULTS: Of the 300 patients with CHIKV infection seen during the study period, June-December 2006, 49 (16.3%) [M : F: 42:7] had neurological complications. The neurological complications included: Encephalitis (27, 55%), myelopathy (7, 14% ), peripheral neuropathy (7, 14%), myeloneuropathy (7, 14%), and myopathy (1, 2%). Reverse Transcriptase polymerase chain reaction (RT-PCR) and real-time PCR was positive in the CSF in 16% and 18%, respectively. CONCLUSION: Recent CHIKV infection was associated with various neurological complications, suggesting neurotropic nature of the virus. The outcome of the neurological complications is likely to be good.

Evaluation of the IS6110 PCR assay for the rapid diagnosis of tuberculous meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is one of the common clinical manifestations of extra-pulmonary tuberculosis. It is difficult to diagnose due to a lack of rapid, sensitive, and specific tests. Newer methods, which are easy and reliable, are required to diagnose TBM at an early stage. Thus our aim was to evaluate the polymerase chain reaction (PCR) technique, using primers directed against the IS6110 gene, for the detection of Mycobacterium tuberculosis in the CSF, for the diagnosis of TBM patients. METHODS: An in-house IS6110 PCR method using a specific pair of primers designed to amplify the insertion sequence, IS6110, in the M. tuberculosis genome was used to analyze CSF. A total of 80 CSF samples from different groups of patients were studied (confirmed TBM n = 35, clinically suspected TBM n = 16, non-TBM infectious meningitis n = 12, non infectious neurological diseases n = 17). RESULTS: PCR gave a sensitivity of 91.4% and specificity of 75.9% for the diagnosis of TBM in patients with TBM confirmed by culture. In 16 clinically diagnosed, but unconfirmed, TBM cases PCR was positive in 10 (62.5%) cases. There were seven (24.1%) PCR-positive cases among the 29 patients with non-TBM and non-infectious neurological disease. CONCLUSION: We conclude that the performance of an in-house IS6110 PCR assay is valuable in the rapid diagnosis of tuberculous meningitis.

Diagnosis of tuberculosis in an Indian population by an indirect ELISA protocol based on detection of Antigen 85 complex: a prospective cohort study.

BACKGROUND: Diagnosis of tuberculosis (TB) remains problematic despite many new advanced diagnostic methods. A reliable and rapid diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain definitive early diagnoses of TB. In the present study we describe a prospective evaluation for demonstrating Antigen (Ag) 85 complex in the sera from TB patients. METHODS: Indirect ELISA, employing monoclonal antibodies (mAb) against the purified Ag 85 complex, was used to demonstrate Ag 85 complex in sera from TB patients. Serum samples were obtained from 197 different groups of patients: confirmed TB {n = 24}, clinically diagnosed TB {n = 104}, disease controls {n = 49} and healthy controls {n = 20}. Receiver operating curve (ROC) was used to calculate the cut off value and comparison between TB and non-TB groups were done by the chi-square test. RESULTS: The indirect ELISA method, using an mAb against Ag 85 complex, yielded 82% sensitivity (95% confidence interval [CI] 67 to 93%) and 86% specificity (95% CI, 57 to 98%) for the diagnosis of TB. The serum positivities for Ag 85 complex in cases of confirmed and clinically diagnosed TB patients were 96% (23/24) and 79% (82/104) respectively, while the positivity for patients in the non-tuberculosis group was 14% (10/69). CONCLUSION: The detection of Ag 85 complex in sera from TB patients by indirect ELISA using mAb against purified Ag 85 complex gives a reliable diagnosis and can be used to develop an immunodiagnostic assay with increased sensitivity and specificity.

Effect of Fagonia Arabica (Dhamasa) on in vitro thrombolysis.

BACKGROUND: Atherothrombotic diseases such as myocardial or cerebral infarction are serious consequences of the thrombus formed in blood vessels. Thrombolytic agents are used to dissolve the already formed clots in the blood vessels; however, these drugs have certain limitations which cause serious and sometimes fatal consequences. Herbal preparations have been used since ancient times for the treatment of several diseases. Herbs and their components possessing antithrombotic activity have been reported before; however, herbs that could be used for thrombolysis has not been reported so far. This study's aim was to investigate whether herbal preparations (aqueous extract) possess thrombolytic activity or not. METHODS: An in vitro thrombolytic model was used to check the clot lysis effect of six aqueous herbal extracts viz., Tinospora cordifolia, Rubia cordifolia, Hemidesmus indicus, Glycyrrhiza glabra Linn, Fagonia Arabica and Bacopa monnieri Linn along with Streptokinase as a positive control and water as a negative control. RESULTS: Using an in vitro thrombolytic model, Tinospora cordifolia, Rubia cordifolia, Hemidesmus indicus, Glycyrrhiza glabra Linn, Fagonia Arabica and Bacopa monnieri Linn showed 19.3%, 14.5%, 20.3%, 17.8%, 75.6% and 41.8% clot lysis respectively . Among the herbs studied Fagonia arabica showed significant % of clot lysis (75.6%) with reference to Streptokinase (86.2%). CONCLUSION: Through our study it was found that Dhamasa possesses thrombolytic properties that could lyse blood clots in vitro; however, in vivo clot dissolving properties and active component(s) of Dhamasa for clot lysis are yet to be discovered. Once found Dhamasa could be incorporated as a thrombolytic agent for the improvement of patients suffering from Atherothrombotic diseases.

Cerebrospinal fluid adenosine deaminase activity: a complimentary tool in the early diagnosis of tuberculous meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is the commonest form of neurotuberculosis caused by Mycobacterium tuberculosis bacilli (MTB). The diagnosis of TBM is often difficult. A reliable, cost-effective and rapid diagnostic test, which can be performed in any standard pathology laboratory, could be of help in the diagnosis of TBM. In the present study we measured the adenosine deaminase (ADA) activity in cerebrospinal fluid (CSF) of TBM and non-TBM patients. METHOD: ADA activity in CSF was determined according to a method based on the Berthlot reaction, which is the formation of a colored indophenol complex from ammonia liberated from adenosine, and quantified spectrophotometrically. RESULTS: The CSF ADA activity from TBM patients was compared with CSF ADA from non-TBM infectious meningitis patients, and from patients with non-infectious neurological disorders. The mean CSF ADA activity was found to be significantly higher in CSF of TBM patients, 14.31 +/- 3.87 (2.99-26.94), mean +/- SD with range, than in the CSF from non-TBM infectious meningitis, 9.25 +/- 2.14 (4.99-13.96) and from the non-infectious neurological disorders group, 2.71 +/- 1.96 (0.00-7.68), P < 0.0001 for both comparisons. A cut-off value of 11.39 U/L/min for the TBM patients was calculated from the mean + SD of the non-TBM patients. The ADA test gave a sensitivity of 82% and a specificity of 83% for infectious TBM when this cut-off value was used. CONCLUSION: This study demonstrated that ADA activity in the CSF of TBM patients, using a cut-off value 11.39 U/L/min, can be useful for the early differential diagnosis of TBM. This test can be performed in any pathology laboratory where more sophisticated methods are not available.

Detection of 65 kD heat shock protein in cerebrospinal fluid of tuberculous meningitis patients.

BACKGROUND: Diagnosis of tuberculous meningitis (TBM) is difficult. Rapid confirmatory diagnosis is essential to initiate required therapy. There are very few published reports about the diagnostic significance of 65 kD heat shock protein (hsp) in TBM patients, which is present in a wide range of Mycobacterium tuberculosis species and elicits a cellular and humoral immune response. In the present study we have conducted a prospective evaluation for the demonstration of 65 kD hsp antigen in cerebrospinal fluid (CSF) of TBM patients, by indirect ELISA method using monoclonal antibodies (mAb) against the 65 kD hsp antigen, for the diagnosis of TBM. METHODS: A total of 160 CSF samples of different groups of patients (confirmed TBM {n = 18}, clinically suspected TBM {n = 62}, non TBM infectious meningitis {n = 35} and non-infectious neurological diseases {n = 45}) were analyzed by indirect ELISA method using mAb to 65 kD hsp antigen. The Kruskal Wallis test (Non-Parametric ANOVA) with the Dunnett post test was used for statistical analysis. RESULTS: The indirect ELISA method yielded 84% sensitivity and 90% specificity for the diagnosis of TBM using mAb to 65 kD hsp antigen. The mean absorbance value of 65 kD hsp antigen in TBM patients was [0.70 +/- 0.23 (0.23-1.29)], significantly higher than the non-TBM infectious meningitis group [0.32 +/- 0.14 (0.12-0.78), P < 0.001] and also higher than the non-infectious neurological disorders group [0.32 +/- 0.13 (0.20-0.78), P < 0.001]. A significant difference in the mean absorbance of 65 kD hsp antigen was noted in the CSF of culture-positive TBM patients [0.94 +/- 0.18 (0.54-1.29)] when compared with clinically suspected TBM patients [0.64 +/- 0.20 (0.23-0.98), P < 0.05]. CONCLUSION: The presence of 65 kD hsp antigen in the CSF of confirmed and suspected cases of TBM would indicate that the selected protein is specific to M. tuberculosis and could be considered as a diagnostic marker for TBM.

Development of an in vitro model to study clot lysis activity of thrombolytic drugs.

BACKGROUND: Thrombolytic drugs are widely used for the management of cerebral venous sinus thrombosis patients. Several in vitro models have been developed to study clot lytic activity of thrombolytic drugs, but all of these have certain limitations. There is need of an appropriate model to check the clot lytic efficacy of thrombolytic drugs. In the present study, an attempt has been made to design and develop a new model system to study clot lysis in a simplified and easy way using a thrombolytic drug, streptokinase. METHODS: Whole blood from healthy individuals (n = 20) was allowed to form clots in a pre-weighed sterile microcentrifuge tubes; serum was removed and clot was weighed. After lysis by streptokinase fluid was removed and remnants of clot were again weighed along with the tube. Percentage of Clot lysis was calculated on the basis of the weight difference of microcentrifuge tubes obtained before and after clot lysis. RESULTS: There was a significant percentage of clot lysis observed when streptokinase was used. On the other hand with water (negative control), minimal (2.5%) clot lysis was observed. There was a significant difference between clot lysis done by streptokinase and water. CONCLUSION: Our study could be a rapid and effective methodology to study clot-lytic effect of newly developed drugs as well as known drugs.

Secretory factors of human neuroblastoma (IMR-32) and human glioblastoma (U87MG) cell lines induce neurite outgrowths in PC12 cells.

Neurite outgrowth is essential for the communication of the nervous system. The rat Pheochromocytoma (PC12) cells are commonly used in the neuronal cell study. It is well known that exogenous stimuli such as Nerve Growth Factor (NGF) induce neurite outgrowth. In the present study it has been investigated whether or not the conditioned medium from human neuroblastoma cell line (IMR-32) and human glioblastoma cell line (U87MG) may augment neurite outgrowth in PC12 cells. PC12 were cultured with and without conditioned media of IMR-32 and U87MG. The result showed that both the conditioned media induce neurite outgrowth within 48 hr and stops further proliferation of PC12 cells. However no outgrowth was noted in PC12 cells incubated without conditioned medium. In conclusion, it is shown that both the conditioned media (IMR-32 and U87MG) have the potential to induce the neurite outgrowth in the PC12 cells.