1.A comparative study between light transmission aggregometry and flow cytometric platelet aggregation test for the identification of platelet function defects in patients with bleeding
Praveen SHARMA ; Man Updesh Singh SACHDEVA ; Narender KUMAR ; Sunil BOSE ; Parveen BOSE ; Varun UPPAL ; Pankaj MALHOTRA ; Deepak BANSAL ; Neelam VARMA ; Jasmina AHLUWALIA
Blood Research 2021;56(2):109-118
Background:
Platelet aggregation studies using conventional light transmission aggregometry (LTA) have several disadvantages and require strict pre-analytical measures for reliable results.We aimed to examine the utility of flow cytometric platelet aggregation (FCA) assay in detecting platelet function defects (PFDs) in patients with a history of bleeding symptoms.
Methods:
Sixty-four participants (24 patients and 40 healthy controls) were included in this study.LTA and FCA assay were performed simultaneously in patients and healthy controls. In the FCA assay, two portions of platelets from the same individual were labeled separately with CD31-FITC and CD31-PE. After mixing and stimulation with agonists, the double-colored platelet aggregates were visualized using a flow cytometer. The results generated using the two techniques were compared and correlated.
Results:
The patients’ median age was 17 years (range, 3‒72 yr) with a male-to-female ratio of 1:1.7. There was substantial agreement between LTA and FCA assay in detecting a PFD (κ=0.792). Four patients showing a Glanzmann thrombasthenia-like pattern on LTA exhibited an abnormal FCA. A functional defect in collagen binding was detected on the FCA assay conducted in two immune thrombocytopenic patients with severe bleeding.
Conclusion
FCA assay can be used to identify functional defects in platelets, with potential applications in thrombocytopenic individuals. It also facilitates the diagnosis of inherited bleeding disorders with platelet defects.
2.A comparative study between light transmission aggregometry and flow cytometric platelet aggregation test for the identification of platelet function defects in patients with bleeding
Praveen SHARMA ; Man Updesh Singh SACHDEVA ; Narender KUMAR ; Sunil BOSE ; Parveen BOSE ; Varun UPPAL ; Pankaj MALHOTRA ; Deepak BANSAL ; Neelam VARMA ; Jasmina AHLUWALIA
Blood Research 2021;56(2):109-118
Background:
Platelet aggregation studies using conventional light transmission aggregometry (LTA) have several disadvantages and require strict pre-analytical measures for reliable results.We aimed to examine the utility of flow cytometric platelet aggregation (FCA) assay in detecting platelet function defects (PFDs) in patients with a history of bleeding symptoms.
Methods:
Sixty-four participants (24 patients and 40 healthy controls) were included in this study.LTA and FCA assay were performed simultaneously in patients and healthy controls. In the FCA assay, two portions of platelets from the same individual were labeled separately with CD31-FITC and CD31-PE. After mixing and stimulation with agonists, the double-colored platelet aggregates were visualized using a flow cytometer. The results generated using the two techniques were compared and correlated.
Results:
The patients’ median age was 17 years (range, 3‒72 yr) with a male-to-female ratio of 1:1.7. There was substantial agreement between LTA and FCA assay in detecting a PFD (κ=0.792). Four patients showing a Glanzmann thrombasthenia-like pattern on LTA exhibited an abnormal FCA. A functional defect in collagen binding was detected on the FCA assay conducted in two immune thrombocytopenic patients with severe bleeding.
Conclusion
FCA assay can be used to identify functional defects in platelets, with potential applications in thrombocytopenic individuals. It also facilitates the diagnosis of inherited bleeding disorders with platelet defects.
3.Inherited thrombophilia profile in patients with recurrent miscarriages: Experience from a tertiary care center in north India.
Narender KUMAR ; Jasmina AHLUWALIA ; Reena DAS ; Meenakshi ROHILLA ; Sunil BOSE ; Hari KISHAN ; Neelam VARMA
Obstetrics & Gynecology Science 2015;58(6):514-517
The cause of recurrent miscarriage (RM) remains unexplained in approximately 30% to 50% cases. The association of inherited thrombotic factors and RM patients has not been documented from the northern part of India. A total of 40 patients had been investigated for inherited thrombophilia workup (protein C, protein S [PS], antithrombin III, and factor V Leiden [FVL] mutation) over a period of 10 years (2005 to 2014). RM patients were divided in to three groups. Group I (only 1st trimester loss), group II (only 2nd and 3rd trimester), and group III (mixed). Each group comprised of the following numbers of patients respectively: I, 24; II, 2; III, 14. Heterozygous FVL mutation was found in 10% (4/40) cases. PS deficiency was detected in 2.7% (1/37) cases. In the present study FVL and PS were seems to be associated with a subset of patients however further studies with larger numbers of patients are recommended for better evaluation.
Abortion, Habitual*
;
Antithrombin III
;
Factor V
;
Female
;
Humans
;
India*
;
Pregnancy
;
Protein S
;
Tertiary Care Centers*
;
Tertiary Healthcare*
;
Thrombophilia*
4.Transcranial Direct Current Stimulation in Schizophrenia.
Sri Mahavir AGARWAL ; Venkataram SHIVAKUMAR ; Anushree BOSE ; Aditi SUBRAMANIAM ; Hema NAWANI ; Harleen CHHABRA ; Sunil V KALMADY ; Janardhanan C NARAYANASWAMY ; Ganesan VENKATASUBRAMANIAN
Clinical Psychopharmacology and Neuroscience 2013;11(3):118-125
Transcranial direct current stimulation (tDCS) is an upcoming treatment modality for patients with schizophrenia. A series of recent observations have demonstrated improvement in clinical status of schizophrenia patients with tDCS. This review summarizes the research work that has examined the effects of tDCS in schizophrenia patients with respect to symptom amelioration, cognitive enhancement and neuroplasticity evaluation. tDCS is emerging as a safe, rapid and effective treatment for various aspects of schizophrenia symptoms ranging from auditory hallucinations-for which the effect is most marked, to negative symptoms and cognitive symptoms as well. An interesting line of investigation involves using tDCS for altering and examining neuroplasticity in patients and healthy subjects and is likely to lead to new insights into the neurological aberrations and pathophysiology of schizophrenia. The mechanistic aspects of the technique are discussed in brief. Future work should focus on establishing the clinical efficacy of this novel technique and on evaluating this modality as an adjunct to cognitive enhancement protocols. Understanding the mechanism of action of tDCS as well as the determinants and neurobiological correlates of clinical response to tDCS remains an important goal, which will help us expand the clinical applications of tDCS for the treatment of patients with schizophrenia.
Hallucinations
;
Humans
;
Neurobehavioral Manifestations
;
Neuronal Plasticity
;
Schizophrenia*
5.Neural Correlates of a Perspective-taking Task Using in a Realistic Three-dimmensional Environment Based Task: A Pilot Functional Magnetic Resonance Imaging Study.
Sri Mahavir AGARWAL ; Venkataram SHIVAKUMAR ; Sunil V KALMADY ; Vijay DANIVAS ; Anekal C AMARESHA ; Anushree BOSE ; Janardhanan C NARAYANASWAMY ; Michel Ange AMORIM ; Ganesan VENKATASUBRAMANIAN
Clinical Psychopharmacology and Neuroscience 2017;15(3):276-281
OBJECTIVE: Perspective-taking ability is an essential spatial faculty that is of much interest in both health and neuropsychiatric disorders. There is limited data on the neural correlates of perspective taking in the context of a realistic three-dimensional environment. We report the results of a pilot study exploring the same in eight healthy volunteers. METHODS: Subjects underwent two runs of an experiment in a 3 Tesla magnetic resonance imaging (MRI) involving alternate blocks of a first-person perspective based allocentric object location memory task (OLMT), a third-person perspective based egocentric visual perspective taking task (VPRT), and a table task (TT) that served as a control. Difference in blood oxygen level dependant response during task performance was analyzed using Statistical Parametric Mapping software, version 12. Activations were considered significant if they survived family-wise error correction at the cluster level using a height threshold of p<0.001, uncorrected at the voxel level. RESULTS: A significant difference in accuracy and reaction time based on task type was found. Subjects had significantly lower accuracy in VPRT compared to TT. Accuracy in the two active tasks was not significantly different. Subjects took significantly longer in the VPRT in comparison to TT. Reaction time in the two active tasks was not significantly different. Functional MRI revealed significantly higher activation in the bilateral visual cortex and left temporoparietal junction (TPJ) in VPRT compared to OLMT. CONCLUSION: The results underscore the importance of TPJ in egocentric manipulation in healthy controls in the context of reality-based spatial tasks.
Healthy Volunteers
;
Magnetic Resonance Imaging*
;
Memory
;
Oxygen
;
Pilot Projects
;
Reaction Time
;
Task Performance and Analysis
;
Visual Cortex