Carrier-frequency estimation for digital holograms of phase objects.

Accurate estimation of carrier fringe frequency is essential for the demodulation of off-axis digital holograms. The fringe frequency is often associated with the amplitude peak of the cross-term in the two-dimensional Fourier transform of a digital hologram. We point out that this definition of carrier frequency is not valid in general for holograms associated with phase objects. We examine the carrier-envelope representation for digital holograms from the viewpoint of Mandel's criterion [J. Opt. Soc. Am.57, 613 (1967)10.1364/JOSA.57.000613]. An appropriate definition of carrier frequency is observed to be the centroid of the power spectrum associated with the cross term. This definition is shown to apply uniformly to holograms associated with phase objects, is robust to noise, and leads to the smoothest (or least fluctuating) envelope representation for the demodulated object wave. The proposed definition is illustrated with simulated as well as experimentally recorded off-axis holograms.

High-Definition Transcranial Direct Current Stimulation-Primed Intermittent Theta Burst Stimulation in Treatment-Resistant Depression: A Controlled Study.

OBJECTIVES: The aim of this study was to evaluate whether high-definition transcranial direct current stimulation (HDtDCS) priming improves the efficacy of intermittent theta burst stimulation (iTBS) in improving TRD. METHODOLOGY: A prospective hospital-based, randomized control study where the participants were divided into active or sham HDtDCS-primed iTBS stimulation groups for a total of 10 sessions and were assessed on clinical parameters at baseline, end of week 1, and end of week 2 was done. Primary outcome of the study was the difference in Hamilton Depression Rating Scale (HDRS) scores over 2 weeks of HDtDCS-primed iTBS. RESULT: A significant effect of time was seen over HDRS scores in both active and sham groups with a large effect size. Significant effect of time was also found over the Clinical Global Impressions-Severity Scale scores of patients with a large effect size. The difference in the improvement in depressive severity as measured using HDRS and Clinical Global Impressions-Severity Scale scores between active and sham groups was also found to be significant with large effect sizes. CONCLUSION: High-definition tDCS-primed iTBS is superior to normal iTBS in patients with depression who have failed a trial of 2 antidepressants, whereas both mechanisms are of benefit to the patients.

Hump on head: Rare case of bi-frontal fibrous dysplasia.

Background: FD is relatively rare in the craniofacial region, accounting for only 20% of all cases. Currently, two general subtypes of FD are recognized: monostotic and polyostotic. The monostotic form is more frequent, accounting for 75% to 80% of fibrous dysplasia cases. Case Description: An 18-year-old male presented with the complaint of bony-hard swelling over the forehead for 8 years. Radiology showed an expansile osseous lesion involving frontal bones. The patient underwent bi-frontal craniectomy with gross total resection of tumour mass with titanium mesh cranioplasty. His postoperative period was uneventful and was discharged on the seventh postoperative day. Conclusion: The cases of monostotic skull fibrous dysplasia should be treated by resection of the affected bone and cranioplasty. However, a more conservative re-contouring may be carried out in cases with multifocal involvement or when the excision is considered risky due to proximity to the major venous sinuses.

Quantification of pollen viability in Lantana camara by digital holographic microscopy.

Pollen grains represent the male gametes of seed plants and their viability is critical for sexual reproduction in the plant life cycle. Palynology and viability studies have traditionally been used to address a range of botanical, ecological and geological questions, but recent work has revealed the importance of pollen viability in invasion biology as well. Here, we report an efficient visual method for assessing the viability of pollen using digital holographic microscopy (DHM). Imaging data reveal that quantitative phase information provided by the technique can be correlated with viability as indicated by the outcome of the colorimetric test. We successfully test this method on pollen grains of Lantana camara, a well-known alien invasive plant in the tropical world. Our results show that pollen viability may be assessed accurately without the usual staining procedure and suggest potential applications of the DHM methodology to a number of emerging areas in plant science.

Metabolic regulation to treat bipolar depression: mechanisms and targeting by trimetazidine.

Bipolar disorder's core feature is the pathological disturbances in mood, often accompanied by disrupted thinking and behavior. Its complex and heterogeneous etiology implies that a range of inherited and environmental factors are involved. This heterogeneity and poorly understood neurobiology pose significant challenges to existing drug development paradigms, resulting in scarce treatment options, especially for bipolar depression. Therefore, novel approaches are needed to discover new treatment options. In this review, we first highlight the main molecular mechanisms known to be associated with bipolar depression-mitochondrial dysfunction, inflammation and oxidative stress. We then examine the available literature for the effects of trimetazidine in said alterations. Trimetazidine was identified without a priori hypothesis using a gene-expression signature for the effects of a combination of drugs used to treat bipolar disorder and screening a library of off-patent drugs in cultured human neuronal-like cells. Trimetazidine is used to treat angina pectoris for its cytoprotective and metabolic effects (improved glucose utilization for energy production). The preclinical and clinical literature strongly support trimetazidine's potential to treat bipolar depression, having anti-inflammatory and antioxidant properties while normalizing mitochondrial function only when it is compromised. Further, trimetazidine's demonstrated safety and tolerability provide a strong rationale for clinical trials to test its efficacy to treat bipolar depression that could fast-track its repurposing to address such an unmet need as bipolar depression.

Prevalence of depression in visually impaired children and adolescents: A systematic review and meta-analysis.

The prevalence of depression among visually impaired or blind children and adolescents has not been systematically reviewed. This study aims to provide the prevalence of depression among visually impaired or blind children and adolescents. This systematic review and meta-analysis were conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines (PRISMA) (2020) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. A systematic search of various online databases was done to identify and include studies reporting the prevalence of depression among visually impaired or blind children and adolescents (aged up to 20 years). A random-effects meta-analysis was used to estimate the pooled prevalence of depression. Heterogeneity was assessed using I2 to explain heterogeneity meta-regressive analysis and subgroup analyses were done. With the finally selected 13 studies consisting of 822 participants, the overall pooled prevalence of depression or dysthymia among visually impaired children or adolescents was 14% (137/822 individuals, 95% CI = 9% to 20%), with high heterogeneity between studies (I2 = 80.11%; P < 0.001). Five studies that expressed gender distribution showed a cumulative prevalence of diagnosed depressive disorders was 6.85% and 18.96%, respectively, for male (n = 219, I2 = 47.52) and female (n = 116, I2 = 60.6%) participants. In this systematic review and meta-analysis, we selected and analyzed 13 studies and estimated pooled prevalence of depression was 14% (95% CI = 9% to 20%), among visually impaired or blind children and adolescents.

Giant Tarlov Cyst presenting as pelvic mass: Often doing less is better.

Background: Tarlov cysts are sacral perineural cysts arising between the peri and endoneurium of the posterior spinal nerve root at the Dorsal Root Ganglion and have a global prevalence rate of 4.27%. These are primarily asymptomatic (only 1% with symptoms) and typically arise in females between the ages of 50-60. Patients' symptoms include radicular pain, sensory dysesthesias, urinary and/or bowel symptoms, and sexual dysfunction. Non-surgical management with lumbar cerebrospinal fluid drainage and computerized tomography-guided cyst aspiration typically provide only months of improvement before recurring. Surgical treatment includes a laminectomy, cyst, and/or nerve root decompression with fenestration of the cyst and/ or imbrication. Early surgery for large cysts provides the longest symptom-free periods. Case Description: A 30-year-old male presented with a very large magnetic resonance-documented Tarlov cyst (Nabors Type 2) arising from bilateral S2 nerve root sheaths with marked pelvic extension. Although he was initially treated with a S1, S2 laminectomy, closure of the dural defect, and excision/marsupialization of the cyst, he later required placement of a thecoperitoneal shunt (TP shunt). Conclusion: A 30-year-old male with large Nabors Type 2 Tarlov cyst arising from both S2 nerve root sheaths required a S1-S2 laminectomy, dural closure/marsupialization, and imbrication of the cyst, eventually followed by placement of a TP shunt.

Indian Psychiatric Society multicentre study: Diagnostic patterns, comorbidity and prescription practices for patients with Dementia.

Background: There are more than 5 million people with dementia in India. Multicentre studies looking at details of treatment for people with dementia In India are lacking. Clinical audit is a quality improvement process which aims to systematically assess, evaluate, and improve patient care. Evaluating current practice is the key to a clinical audit cycle. Aim: This study aimed to assess the diagnostic patterns and prescribing practices of psychiatrists for patients with dementia in India. Method: A retrospective case file study was conducted across several centers in India. Results: Information from the case records of 586 patients with dementia was obtained. Mean age of the patients was 71.14 years (standard deviation = 9.42). Three hundred twenty one (54.8%) were men. Alzheimer's disease (349; 59.6%) was the most frequent diagnosis followed by vascular dementia (117; 20%). Three hundred fifty five (60.6%) patients had medical disorders and 47.4% patients were taking medications for their medical conditions. Eighty one (69.2%) patients with vascular dementia had cardiovascular problems. Majority of the patients (524; 89.4%) were on medications for dementia. Most frequently prescribed treatment was Donepezil (230; 39.2%) followed by Donepezil-Memantine combination (225; 38.4%). Overall, 380 (64.8%) patients were on antipsychotics. Quetiapine (213, 36.3%) was the most frequently used antipsychotic. Overall, 113 (19.3%) patients were on antidepressants, 80 (13.7%) patients were on sedatives/hypnotics, and 16 (2.7%) patients were on mood stabilizers. Three hundred nineteen (55.4%) patients and caregivers of 374 (65%) patients were receiving psychosocial interventions. Conclusions: Diagnostic and prescription patterns in dementia which emerged from this study are comparable to other studies both nationally and internationally. Comparing current practices at individual and national levels against accepted guidelines, obtaining feedback, identifying gaps and instituting remedial measures help to improve the standard of care provided.

Brain activation alterations with adjunctive deep transcranial magnetic stimulation in obsessive-compulsive disorder: an fMRI study.

BACKGROUND: Obsessive-compulsive disorder (OCD) is one of the most common neuropsychiatric disorders with lifetime prevalence higher than that of schizophrenia and bipolar disorders. Inadequate response to available pharmacological and psychotherapeutic interventions is common in OCD. Adjunctive brain stimulation methods to address the inadequate treatment response in OCD have found a special interest in research. This study aimed to examine the efficacy of adjunctive deep transcranial magnetic stimulation (dTMS) in ameliorating the symptoms of OCD and the effect of dTMS on activation of brain regions while performing the Stroop task using functional magnetic resonance imaging (fMRI). METHODS: A total of 41 patients were assessed for the study out of which 15 OCD patients received 10 sessions of high-frequency dTMS using the H7 coil to target the anterior cingulate cortex and the medial prefrontal cortex over a period of 2 weeks. The Yale-Brown Obsessive-Compulsive Scale, the Hamilton Anxiety Rating Scale, and the Hamilton Depression Rating Scale were used for the pre- and post-stimulation clinical assessment. fMRI was used to measure the activation of brain regions while performing the Stroop task. RESULTS: There was a significant improvement in the obsessive-compulsive, anxiety, and depressive symptoms after the 2 weeks of the dTMS treatment. A significant decrease in the activation of left caudate nucleus and adjacent white matter was noted while performing the Stroop task after the dTMS treatment. CONCLUSION: The study provides preliminary evidence for functional correlates of effectiveness of dTMS as an adjunctive treatment modality for OCD.

Nerve Growth Factor in Psychiatric Disorders: A Scoping Review.

Background: Neurotrophins have been implicated in multiple psychiatric disorders. Nerve Growth Factor (NGF) is one of the major neurotrophins that has attracted much research interest. Therefore, we undertook, to the best of our knowledge, the first scoping review encompassing all major psychiatric disorders and their relation to NGF. This review aimed to identify the current position of NGF in psychiatric research and to outline present gaps in knowledge, which can be answered with a more detailed systematic review in the future. Methods: Suitable studies were identified using PubMed. A total of 20 studies were included in the review: two on bipolar affective disorder (BPAD), three on schizophrenia, seven on depression, and eight on alcohol use disorder. Results: NGF levels are definitively reduced in BPAD and depression, while NGF levels in schizophrenia decreased further after treatment than in the drug-naïve state. The effect of treatment on NGF levels in depression varied based on treatment modalities and severity of depression. In patients with depression, raised NGF was a predictor of conversion to bipolar disorder (BD). NGF levels were raised in acute alcohol intoxication and withdrawal but normalized slowly as abstinence was maintained. NGF may play a protective role in preventing the toxic ill effect of acute alcohol intoxication on the central nervous system. Conclusion: Based on current knowledge, NGF levels may be a useful biomarker of a chronic mental stress condition. However, further research is needed before it can be used to identify a specific psychiatric illness or predict treatment response.

Need to Incorporate Endovascular Neurosurgery in Neurosurgery Curriculum in India: Stay Abreast or be Left Behind.

Endovascular neurosurgery is one of the most rapidly evolving subspecialties in the field of neurosurgery. Since its inception, it has taken up almost 50%-60% of the cerebrovascular workload. Various specialties are competing to claim this field; still, no one can argue against a neurosurgeon's suitability in performing endovascular techniques. Currently, the field is shared between neurosurgeons and neuroradiologists, each getting different pie shares in various parts of the world. However, in India, barring a few residency programs, most neurosurgery programs offer little or no exposure to endovascular techniques. There is an urgent need for endovascular neurosurgery to be incorporated in the neurosurgery training curriculum in the country. Performing DSAs is the first step toward starting an endovascular neurosurgery unit. We have presented here the data of the DSAs done by a single neurosurgeon over almost 3 years. We have discussed our experience in the hope that fellow neurosurgeons across the country find it useful.

Research on treatment-related aspects of depression from India in the preceding decade (2014-2023): An updated systematic review.

Background: The National Mental Health Survey reports a prevalence of 2.7% for depressive disorders in India. The services for depression patients may be organized differently in India as compared to Western countries. It is important to consider studies conducted in India to determine effective interventions for depression catered specifically to the needs of the Indian population. We intended to systematically review the articles studying the usefulness of various treatment modalities in the management of depression in the Indian context. Materials and Methods: We searched PubMed, Google Scholar, and ScienceDirect to identify studies published in peer-reviewed English language journals. All articles from India evaluating the clinical efficacy of anti-depressants, electro-convulsive therapy, repetitive transcranial magnetic stimulation, and psychological interventions for the management of depression were evaluated. Data were extracted using standard procedures. Results: A total of 36 studies were included in the review. Out of those, 15 were studies on drug efficacy, five on neuro-modulation, nine on psycho-social interventions, four on adverse effects, and three on miscellaneous studies. Innovations were seen in the field of neuro-modulation and psycho-social intervention. Trials on drug efficacy and adverse drug reactions require larger sample sizes, more studies on newer agents, and more robust study designs. Conclusion: More research is needed to understand the effectiveness and potential negative effects of depression treatments in India. Studies on ketamine have been inconclusive, and existing research on pharmacological agents is limited. Neuro-modulation studies show promise, but larger-scale studies are needed. Innovative psychological interventions tailored to the Indian population include community-based and digital technology-driven care.