John John - Academia.edu (original) (raw)
Papers by John John
Cognitive deficits are established as a fundamental feature of schizophrenia; however, their patt... more Cognitive deficits are established as a fundamental feature of schizophrenia; however, their pattern and how they are affected by chronicity are still unclear. Although a generalized stable impairment affecting multiple cognitive domains is commonly seen from the onset, some longitudinal studies have shown evidence of neuroprogression, and selective deterioration in certain cognitive domains. We assessed cognitive performance in patients with recent-onset (n = 17, duration of illness ≤ 2 years) and chronic schizophrenia (n = 14, duration ≥ 15 years), and healthy adults (n = 16) using the Global Neuropsychological Assessment and examined correlations between cognitive scores and gray matter volumes computed from T1-weighted MRI images. We also measured and analyzed differences between patient groups for negative and positive symptoms, psychotic exacerbations, and medication exposure, and studied their correlations with cognitive performances. We observed cognitive deficits affecting ...
Journal of Evidence Based Medicine and Healthcare
BACKGROUND COVID-19 is associated with a hypercoagulable state and stroke is one of its most comm... more BACKGROUND COVID-19 is associated with a hypercoagulable state and stroke is one of its most common neurological complications. The current study is aimed at investigating the effect of the COVID-19 pandemic on hospital admissions for stroke. METHODS We conducted a retrospective observational study to determine if there was a significant difference in the number of hospital admissions for stroke during the 2 months of lockdown and the two preceding months, (starting on 24 March 2020). The numbers were also compared with the figures during the same months in the previous year. The numbers were also compared to the same months one year prior. The secondary objectives were to compare the time between the onset of stroke and presentation to the hospital, type of strokes that presented to the hospital, severity of stroke, number of code activations, number of thrombolysis conducted, and in-hospital mortality between the same time periods. RESULTS The total number of patients admitted for...
Brain Imaging and Behavior
Amnestic Mild Cognitive Impairment (aMCI) represents the transition between healthy aging and Alz... more Amnestic Mild Cognitive Impairment (aMCI) represents the transition between healthy aging and Alzheimer's dementia (AD) wherein gradual impairment of cognitive abilities, especially memory sets in. Impairment in episodic memory, especially delayed recall, is a hallmark of AD and therefore, patients with aMCI with more severe impairment in episodic memory are considered to be at greater risk of imminent conversion to AD. Brain structural and functional abnormalities were examined by comparing gray matter volumes, white matter micro-structural integrity and resting state functional connectivity (rsFC), between patients with aMCI (n = 46) having lower vs. higher episodic memory delayed recall (EM-DR) performance scores, correcting the influences of age, sex, number of years of formal education and total brain volumes using voxel-based morphometry, whole-brain tract based spatial statistics and dual regression analysis respectively. 'Low' performers (n = 27) when compared to 'high' performers (n = 19) showed significantly increased rsFC in the dorsal attention network (DAN) and central executive network (CEN) in the absence of demonstrable gray matter volumetric or white matter micro-structural integrity differences at family-wise error (FWE) corrected (p < 0.05) significance threshold. Follow-up data available for 38 (low performers = 22; high performers = 16) of the above 46 subjects (82.60% follow-up rate) over a median follow-up period of 24.5 months revealed that 7 subjects (18.42%) had converted to dementia. These converted subjects included 5 of the 22 low performers (22.72%) and 2 of the 16 high performers (12.5%) within the follow-up sample (n = 38). The results of the study indicate that imminent conversion of aMCI to dementia is higher in low performers in comparison to high performers, which may be characterized by increased rsFC in task positive networks, viz., DAN and CEN, as opposed to gray or white matter structural changes. This finding, therefore, might be considered as a prognostic indicator of progression from aMCI to dementia.
BMJ case reports, Jan 16, 2018
Pericardial effusion can develop during any stage of pericarditis, and small effusions that appea... more Pericardial effusion can develop during any stage of pericarditis, and small effusions that appear rapidly can cause cardiac tamponade. Pyopericardium is a rare aetiology for tamponade. This is a case of an elderly diabetic lady, on steroid therapy for immune thrombocytopenia, who presented with fever and acute dyspnoea. She developed cardiac tamponade due to pyopericardium with as the causative organism. pyopericardium, in the absence of a primary focus of infection, progressing to tamponade is an uncommon scenario.
BMC psychiatry, Apr 18, 2018
There is emerging evidence that there are shared genetic, environmental and developmental risk fa... more There is emerging evidence that there are shared genetic, environmental and developmental risk factors in psychiatry, that cut across traditional diagnostic boundaries. With this background, the Discovery biology of neuropsychiatric syndromes (DBNS) proposes to recruit patients from five different syndromes (schizophrenia, bipolar disorder, obsessive compulsive disorder, Alzheimer's dementia and substance use disorders), identify those with multiple affected relatives, and invite these families to participate in this study. The families will be assessed: 1) To compare neuro-endophenotype measures between patients, first degree relatives (FDR) and healthy controls., 2) To identify cellular phenotypes which differentiate the groups., 3) To examine the longitudinal course of neuro-endophenotype measures., 4) To identify measures which correlate with outcome, and 5) To create a unified digital database and biorepository. The identification of the index participants will occur at wel...
Sleep Medicine
Sleep offers a unique window into the brain dysfunctions in schizophrenia. Many past sleep studie... more Sleep offers a unique window into the brain dysfunctions in schizophrenia. Many past sleep studies have reported abnormalities in both macro-sleep architecture (like increased awakenings) as well as micro-sleep-architecture (like spindle deficits) in patients with schizophrenia (PSZ). The present study attempts to replicate previous reports of macro- and micro-sleep-architectural abnormalities in schizophrenia. In addition, the study also examined sleep-stage changes and spindle-delta dynamics across sleep-cycles to provide further evidence in support of the dysfunctional thalamocortical mechanisms causing sleep instability and poor sleep maintenance associated with schizophrenia pathophysiology. Whole-night polysomnography was carried out among 45 PSZ and 39 age- and gender-matched healthy control subjects. Sleep-stage dynamics were assessed across sleep-cycles using a customized software algorithm. Spindle-delta dynamics across sleep-cycles were determined using neuroloop-gain analysis. PSZ showed macro-sleep architecture abnormalities such as prolonged sleeplessness, increased intermittent-awakenings, long sleep-onset latency, reduced non-rapid eye movement (NREM) stage 2 sleep, increased stage transitions, and poor sleep efficiency. They also showed reduced spindle density (sigma neuroloop-gain) but comparable slow wave density (delta neuroloop-gain) throughout the sleep. Sleep-cycle-wise analysis revealed transient features of sleep instability due to significantly increased intermittent awakenings especially in the first and third sleep-cycles, and unstable and recurrent stage transitions in both NREM (first sleep-cycle) and rapid eye movement (REM) sleep-periods (second sleep-cycle). Spindle deficits were persistent across the first three cycles and were positively correlated with sleep disruption during the subsequent REM sleep. In addition to replicating previously reported sleep deficits in PSZ, the current study showed subtle deficits in NREM-REM alterations across whole-night polysomnography. These results point towards a possible maladaptive interplay between unstable thalamocortical networks, resulting in sleep-cycle-specific instability patterns associated with schizophrenia pathophysiology.
Indian journal of orthopaedics
Perioperative blood loss and postoperative pain following total knee arthroplasty prevent early m... more Perioperative blood loss and postoperative pain following total knee arthroplasty prevent early mobilisation of patients. The Enhanced Recovery Protocol (ERP) followed for patients in our institute aims at reducing post operative pain, blood loss and length of stay. 50 consecutive patients that underwent ERP following total knee arthroplasty with another group of 70 patients that underwent the same surgery without ERP were compared in terms of hidden blood loss and length of hospital stay. Hidden blood loss was calculated according to previously described method. Reduction in blood loss was found in both males (305 ml) and females (150 ml) following ERP. Length of stay reduced by 1.5 days in both genders. Regression analysis showed a significant correlation between body weight and blood loss in females. Enhanced recovery protocol could be a useful tool to reduce patient morbidity and reduce length of inpatient stay.
TRATAMIENTO TERMICO. Conjunto de calentamientos y enfriamientos controlados a que puede ser somet... more TRATAMIENTO TERMICO. Conjunto de calentamientos y enfriamientos controlados a que puede ser sometida una aleación sólida con el fin de modificar su estructura micrográfica (y en consecuencia sus propiedades), sin que cambie la composición química de la aleación. En el caso de los aceros se basan en la serie de transformaciones que puede experimentar la austenita en función de las condiciones de enfriamiento. Se reserva el nombre de TRATAMIENTOS TERMOMECÁNICOS para aquellos que producen modificaciones estructurales de la aleación por calentamiento y, simultáneamente, conformación mecánica de la aleación sólida antes del enfriamiento Se denominan TRATAMIENTOS TERMOQUÍMICOS los que comportan además, una modificación química en la periferia de la aleación. TEMPLE+REVENIDO BONIFICADO DEL ACERO
Cognitive deficits are established as a fundamental feature of schizophrenia; however, their patt... more Cognitive deficits are established as a fundamental feature of schizophrenia; however, their pattern and how they are affected by chronicity are still unclear. Although a generalized stable impairment affecting multiple cognitive domains is commonly seen from the onset, some longitudinal studies have shown evidence of neuroprogression, and selective deterioration in certain cognitive domains. We assessed cognitive performance in patients with recent-onset (n = 17, duration of illness ≤ 2 years) and chronic schizophrenia (n = 14, duration ≥ 15 years), and healthy adults (n = 16) using the Global Neuropsychological Assessment and examined correlations between cognitive scores and gray matter volumes computed from T1-weighted MRI images. We also measured and analyzed differences between patient groups for negative and positive symptoms, psychotic exacerbations, and medication exposure, and studied their correlations with cognitive performances. We observed cognitive deficits affecting ...
Journal of Evidence Based Medicine and Healthcare
BACKGROUND COVID-19 is associated with a hypercoagulable state and stroke is one of its most comm... more BACKGROUND COVID-19 is associated with a hypercoagulable state and stroke is one of its most common neurological complications. The current study is aimed at investigating the effect of the COVID-19 pandemic on hospital admissions for stroke. METHODS We conducted a retrospective observational study to determine if there was a significant difference in the number of hospital admissions for stroke during the 2 months of lockdown and the two preceding months, (starting on 24 March 2020). The numbers were also compared with the figures during the same months in the previous year. The numbers were also compared to the same months one year prior. The secondary objectives were to compare the time between the onset of stroke and presentation to the hospital, type of strokes that presented to the hospital, severity of stroke, number of code activations, number of thrombolysis conducted, and in-hospital mortality between the same time periods. RESULTS The total number of patients admitted for...
Brain Imaging and Behavior
Amnestic Mild Cognitive Impairment (aMCI) represents the transition between healthy aging and Alz... more Amnestic Mild Cognitive Impairment (aMCI) represents the transition between healthy aging and Alzheimer's dementia (AD) wherein gradual impairment of cognitive abilities, especially memory sets in. Impairment in episodic memory, especially delayed recall, is a hallmark of AD and therefore, patients with aMCI with more severe impairment in episodic memory are considered to be at greater risk of imminent conversion to AD. Brain structural and functional abnormalities were examined by comparing gray matter volumes, white matter micro-structural integrity and resting state functional connectivity (rsFC), between patients with aMCI (n = 46) having lower vs. higher episodic memory delayed recall (EM-DR) performance scores, correcting the influences of age, sex, number of years of formal education and total brain volumes using voxel-based morphometry, whole-brain tract based spatial statistics and dual regression analysis respectively. 'Low' performers (n = 27) when compared to 'high' performers (n = 19) showed significantly increased rsFC in the dorsal attention network (DAN) and central executive network (CEN) in the absence of demonstrable gray matter volumetric or white matter micro-structural integrity differences at family-wise error (FWE) corrected (p < 0.05) significance threshold. Follow-up data available for 38 (low performers = 22; high performers = 16) of the above 46 subjects (82.60% follow-up rate) over a median follow-up period of 24.5 months revealed that 7 subjects (18.42%) had converted to dementia. These converted subjects included 5 of the 22 low performers (22.72%) and 2 of the 16 high performers (12.5%) within the follow-up sample (n = 38). The results of the study indicate that imminent conversion of aMCI to dementia is higher in low performers in comparison to high performers, which may be characterized by increased rsFC in task positive networks, viz., DAN and CEN, as opposed to gray or white matter structural changes. This finding, therefore, might be considered as a prognostic indicator of progression from aMCI to dementia.
BMJ case reports, Jan 16, 2018
Pericardial effusion can develop during any stage of pericarditis, and small effusions that appea... more Pericardial effusion can develop during any stage of pericarditis, and small effusions that appear rapidly can cause cardiac tamponade. Pyopericardium is a rare aetiology for tamponade. This is a case of an elderly diabetic lady, on steroid therapy for immune thrombocytopenia, who presented with fever and acute dyspnoea. She developed cardiac tamponade due to pyopericardium with as the causative organism. pyopericardium, in the absence of a primary focus of infection, progressing to tamponade is an uncommon scenario.
BMC psychiatry, Apr 18, 2018
There is emerging evidence that there are shared genetic, environmental and developmental risk fa... more There is emerging evidence that there are shared genetic, environmental and developmental risk factors in psychiatry, that cut across traditional diagnostic boundaries. With this background, the Discovery biology of neuropsychiatric syndromes (DBNS) proposes to recruit patients from five different syndromes (schizophrenia, bipolar disorder, obsessive compulsive disorder, Alzheimer's dementia and substance use disorders), identify those with multiple affected relatives, and invite these families to participate in this study. The families will be assessed: 1) To compare neuro-endophenotype measures between patients, first degree relatives (FDR) and healthy controls., 2) To identify cellular phenotypes which differentiate the groups., 3) To examine the longitudinal course of neuro-endophenotype measures., 4) To identify measures which correlate with outcome, and 5) To create a unified digital database and biorepository. The identification of the index participants will occur at wel...
Sleep Medicine
Sleep offers a unique window into the brain dysfunctions in schizophrenia. Many past sleep studie... more Sleep offers a unique window into the brain dysfunctions in schizophrenia. Many past sleep studies have reported abnormalities in both macro-sleep architecture (like increased awakenings) as well as micro-sleep-architecture (like spindle deficits) in patients with schizophrenia (PSZ). The present study attempts to replicate previous reports of macro- and micro-sleep-architectural abnormalities in schizophrenia. In addition, the study also examined sleep-stage changes and spindle-delta dynamics across sleep-cycles to provide further evidence in support of the dysfunctional thalamocortical mechanisms causing sleep instability and poor sleep maintenance associated with schizophrenia pathophysiology. Whole-night polysomnography was carried out among 45 PSZ and 39 age- and gender-matched healthy control subjects. Sleep-stage dynamics were assessed across sleep-cycles using a customized software algorithm. Spindle-delta dynamics across sleep-cycles were determined using neuroloop-gain analysis. PSZ showed macro-sleep architecture abnormalities such as prolonged sleeplessness, increased intermittent-awakenings, long sleep-onset latency, reduced non-rapid eye movement (NREM) stage 2 sleep, increased stage transitions, and poor sleep efficiency. They also showed reduced spindle density (sigma neuroloop-gain) but comparable slow wave density (delta neuroloop-gain) throughout the sleep. Sleep-cycle-wise analysis revealed transient features of sleep instability due to significantly increased intermittent awakenings especially in the first and third sleep-cycles, and unstable and recurrent stage transitions in both NREM (first sleep-cycle) and rapid eye movement (REM) sleep-periods (second sleep-cycle). Spindle deficits were persistent across the first three cycles and were positively correlated with sleep disruption during the subsequent REM sleep. In addition to replicating previously reported sleep deficits in PSZ, the current study showed subtle deficits in NREM-REM alterations across whole-night polysomnography. These results point towards a possible maladaptive interplay between unstable thalamocortical networks, resulting in sleep-cycle-specific instability patterns associated with schizophrenia pathophysiology.
Indian journal of orthopaedics
Perioperative blood loss and postoperative pain following total knee arthroplasty prevent early m... more Perioperative blood loss and postoperative pain following total knee arthroplasty prevent early mobilisation of patients. The Enhanced Recovery Protocol (ERP) followed for patients in our institute aims at reducing post operative pain, blood loss and length of stay. 50 consecutive patients that underwent ERP following total knee arthroplasty with another group of 70 patients that underwent the same surgery without ERP were compared in terms of hidden blood loss and length of hospital stay. Hidden blood loss was calculated according to previously described method. Reduction in blood loss was found in both males (305 ml) and females (150 ml) following ERP. Length of stay reduced by 1.5 days in both genders. Regression analysis showed a significant correlation between body weight and blood loss in females. Enhanced recovery protocol could be a useful tool to reduce patient morbidity and reduce length of inpatient stay.
TRATAMIENTO TERMICO. Conjunto de calentamientos y enfriamientos controlados a que puede ser somet... more TRATAMIENTO TERMICO. Conjunto de calentamientos y enfriamientos controlados a que puede ser sometida una aleación sólida con el fin de modificar su estructura micrográfica (y en consecuencia sus propiedades), sin que cambie la composición química de la aleación. En el caso de los aceros se basan en la serie de transformaciones que puede experimentar la austenita en función de las condiciones de enfriamiento. Se reserva el nombre de TRATAMIENTOS TERMOMECÁNICOS para aquellos que producen modificaciones estructurales de la aleación por calentamiento y, simultáneamente, conformación mecánica de la aleación sólida antes del enfriamiento Se denominan TRATAMIENTOS TERMOQUÍMICOS los que comportan además, una modificación química en la periferia de la aleación. TEMPLE+REVENIDO BONIFICADO DEL ACERO