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Fibroblast-activated protein (FAP) expression in glial cells is attributed to FAP-positive foci on tumor vessels and neoplastic cells. Preclinical and pilot studies have shown FAP expression in high-grade gliomas. We aimed at comparing PET imaging with FAP-inhibitor (FAPI-PET) with current standard, i.e., fluoro-ethyl tyrosine (FET) PET in post-treatment setting to differentiate recurrence and post-treatment changes. 6 patients with WHO Grade III and IV glioma who received standard treatment underwent Ga-68-FAPI-04 PET/CT (FAPI-PET/CT). Tracer uptake greater than background was considered positive. FET PET was performed and interpreted as per institutional standards, which formed the basis of treatment decision. There was concordance between FAPI expression and FET uptake in 5 patients suggestive of disease recurrence. There was no FAPI expression seen in 1 patient, in whom FET PET was suggestive of post-treatment changes. FAPI PET uptake correlated with amino acid expression to differentiate post treatment changes from recurrence in high-grade glial tumors; further validation with prospective study and histopathological confirmation is needed.

Aim: Early diagnosis of paediatric brain tumors significantly improves the outcome. The aim is to study magnetic resonance imaging (MRI) features of paediatric brain tumors and to develop an automated segmentation (AS) tool which could segment and classify tumors using deep learning methods and compare with radiologist assessment. Methods: This study included 94 cases, of which 75 were diagnosed cases of ependymoma, medulloblastoma, brainstem glioma, and pilocytic astrocytoma and 19 were normal MRI brain cases. The data was randomized into training data, 64 cases; test data, 21 cases and validation data, 9 cases to devise a deep learning algorithm to segment the paediatric brain tumor. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the deep learning model were compared with radiologist’s findings. Performance evaluation of AS was done based on Dice score and Hausdorff95 distance. Results: Analysis of MRI semantic features was done with necrosis and haemorrhage as predicting features for ependymoma, diffusion restriction and cystic changes were predictors for medulloblastoma. The accuracy of detecting abnormalities was 90%, with a specificity of 100%. Further segmentation of the tumor into enhancing and non-enhancing components was done. The segmentation results for whole tumor (WT), enhancing tumor (ET), and non-enhancing tumor (NET) have been analyzed by Dice score and Hausdorff95 distance. The accuracy of prediction of all MRI features was compared with experienced radiologist’s findings. Substantial agreement observed between the classification by model and the radiologist’s given classification [K-0.695 (K is Cohen’s kappa score for interrater reliability)]. Conclusions: The deep learning model had very high accuracy and specificity for predicting the magnetic resonance (MR) characteristics and close to 80% accuracy in predicting tumor type. This model can serve as a potential tool to make a timely and accurate diagnosis for radiologists not trained in neuroradiology.

Partial nephrectomy, also called Kidney-sparing Surgery (KSS) or Nephron-sparing Surgery (NSS), is an operation wherein, only a cancerous renal tumour or diseased renal tissue is surgically removed; leaving behind as much healthy renal tissue as possible. Understandably, it was initially preferred in patients with solitary kidney and those, with concurrent bilateral tumours. Over the first two decades of the 21st century, Partial Nephrectomy (PN) has become the standard procedure for many renal tumours; even in unilateral disease. This is because of early pick up due to significant developments in imaging modalities and also, due to better understanding of the biology of renal tumours. With advances in minimal access surgery, partial nephrectomy too has come under its ambit. In the present case series, it's fascinating journey has been discussed- its exciting rise, subsequent downfall and then its unique rise again; as the preferred surgical therapy for many renal tumours, around the world. The purpose of reporting the present case series on Laparoscopic Partial Nephrectomy (LPN) performed for renal cancer, was to share the authors’ early experience and results on the topic and to compare them with the world literature. Also, the aim was to underscore the fact that, in an advanced laparoscopy set up, with optimum patient selection and availability of advanced laparoscopic skills, it is an effective and feasible operation. Herein, the authors have described three cases of totally LPN and review of literature on the same. Over an average follow-up period of 23 months, all three patients continue to be asymptomatic and disease free.

Abstract Background Gliomas are among the most typical brain tumors tackled by neurosurgeons. During navigation for surgery of glioma brain tumors, preoperatively acquired static images may not be accurate due to shifts. Surgeons use intraoperative imaging technologies (2-Dimensional and navigated 3-Dimensional ultrasound) to assess and guide resections. This paper aims to precisely capture the importance of preoperative parameters to decide which type of ultrasound to be used for a particular surgery. Methods This paper proposes two bagging algorithms considering base classifier logistic regression and random forest. These algorithms are trained on different subsets of the original data set. The goodness of fit of Logistic regression-based bagging algorithms is established using hypothesis testing. Furthermore, the performance measures for random-forest-based bagging algorithms used are AUC under ROC and AUC under the precision-recall curve. We also present a composite model without compromising the explainability of the models. Results These models were trained on the data of 350 patients who have undergone brain surgery from 2015 to 2020. The hypothesis test shows that a single parameter is sufficient instead of all three dimensions related to the tumor ( $$p < 0.05$$ p < 0.05 ). We observed that the choice of intraoperative ultrasound depends on the surgeon making a choice, and years of experience of the surgeon could be a surrogate for this dependence. Conclusion This study suggests that neurosurgeons may not need to focus on a large set of preoperative parameters in order to decide on ultrasound. Moreover, it personalizes the use of a particular ultrasound option in surgery. This approach could potentially lead to better resource management and help healthcare institutions improve their decisions to make the surgery more effective.

Background: Neurocognitive function (NCF) before surgery is an important marker of baseline performance in patients with brain tumors. Increasingly, neurocognitive deficits (NCD) have been demonstrated in a high proportion of patients. Selection bias (patient, tumor, and surgical procedure related) may influence the prevalence and type of domains involved in patients with gliomas. Methods: We evaluated baseline NCF in a consecutive cohort of intra-axial tumors in Indian patients (n = 142). A comprehensive battery evaluating five domains – attention & executive function (EF), memory, language, visuospatial function and visuomotor abilities was used. Deficits were categorized as severe and mild-moderate. Factors associated with severe NCD were evaluated. Results: Severe NCD was present in 90% of the patients, 70% of them having affection of at least 2 domains. Attention-EF, memory and visuomotor speed were most affected. 132 underwent surgery (69 awake, 63 under general anesthesia - GA). The awake cohort had younger patients with lower grade gliomas and more left sided tumors. Multi-domain dysfunction was seen almost equally in awake/GA groups as well as left/right sided tumors. On multivariate analysis, older age, lower educational status and larger tumor volume adversely affected NCF in many of the domains. Only language dysfunction was location specific (temporal lobe tumors) though not laterality (left/right) specific. Conclusions: NCD were seen in a large majority of cases before surgery, including those undergoing awake surgery. Language may be affected even in tumors in the non-dominant hemisphere. Attention-EF and memory are most affected and need to be factored in while assessing patient performance intraoperatively during awake surgery as well as tailoring rehabilitative measures subsequently.

IntroductionConventional magnetic resonance imaging (MRI) has limitations in differentiating tumor recurrence (TR) from radionecrosis (RN) in high-grade gliomas (HGG), which can present with morphologically similar appearances. Multiparametric advanced MR sequences and Positron Emission Tomography (PET) with amino acid tracers can aid in diagnosing tumor metabolism. The role of both modalities on an individual basis and combined performances were investigated in the current study.Materials and MethodsPatients with HGG with MRI and PET within three weeks were included in the retrospective analysis. The multiparametric MRI included T1-contrast, T2-weighted sequences, perfusion, diffusion, and spectroscopy. MRI was interpreted by a neuroradiologist without using information from PET imaging. 18F-Fluoroethyl-Tyrosine (FET) uptake was calculated from the areas of maximum enhancement/suspicion, which was assessed by a nuclear medicine physician (having access to MRI to determine tumor-to-white matter ratio over a specific region). A definitive diagnosis of TR or RN was made based on the combination of multidisciplinary joint clinic decisions, histopathological examination, and clinic-radiological follow-up as applicable.Results62 patients were included in the study between July 2018 and August 2021. The histology during initial diagnosis was glioblastoma, oligodendroglioma, and astrocytoma in 43, 7, and 6 patients, respectively, while in 6, no definitive histological characterization was available. The median time from radiation (RT) was 23 months. 46 and 16 patients had TR and RN recurrence, respectively. Sensitivity, specificity, and accuracy using MRI were 98, 77, and 94%, respectively. Using PET imaging with T/W cut-off of 2.65, sensitivity, specificity, and accuracy were 79, 84, and 80%, respectively. The best results were obtained using both imaging combined with sensitivity, specificity, and accuracy of 98, 100, and 98%, respectively.ConclusionCombined imaging with MRI and FET-PET offers multiparametric assessment of glioma recurrence that is correlative and complimentary, with higher accuracy and clinical value.

Meningioma, a primary brain tumor, is commonly encountered and accounts for 39% of overall CNS tumors. Despite significant progress in clinical research, conventional surgical and clinical interventions remain the primary treatment options for meningioma. Several proteomics and transcriptomics studies have identified potential markers and altered biological pathways; however, comprehensive exploration and data integration can help to achieve an in-depth understanding of the altered pathobiology. This study applied integrated meta-analysis strategies to proteomic and transcriptomic datasets comprising 48 tissue samples, identifying around 1832 common genes/proteins to explore the underlying mechanism in high-grade meningioma tumorigenesis. The in silico pathway analysis indicated the roles of extracellular matrix organization (EMO) and integrin binding cascades in regulating the apoptosis, angiogenesis, and proliferation responsible for the pathobiology. Subsequently, the expression of pathway components was validated in an independent cohort of 32 fresh frozen tissue samples using multiple reaction monitoring (MRM), confirming their expression in high-grade meningioma. Furthermore, proteome-level changes in EMO and integrin cell surface interactions were investigated in a high-grade meningioma (IOMM-Lee) cell line by inhibiting integrin-linked kinase (ILK). Inhibition of ILK by administrating Cpd22 demonstrated an anti-proliferative effect, inducing apoptosis and downregulating proteins associated with proliferation and metastasis, which provides mechanistic insight into the disease pathophysiology.

Background The extent of resection for brain tumors is a critical factor in determining the oncologic outcome for a patient. However, a balance between preservation of neurological function and maximal resection is essential for true benefit.

Background and purposeSemantic imaging features have been used for molecular subclassification of high-grade gliomas. Radiomics-based prediction of molecular subgroups has the potential to strategize and individualize therapy. Using MRI texture features, we propose to distinguish between IDH wild type and IDH mutant type high grade gliomas.MethodsBetween 2013 and 2020, 100 patients were retrospectively analyzed for the radiomics study. Immunohistochemistry of the pathological specimen was used to initially identify patients for the IDH mutant/wild phenotype and was then confirmed by Sanger’s sequencing. Image texture analysis was performed on contrast-enhanced T1 (T1C) and T2 weighted (T2W) MR images. Manual segmentation was performed on MR image slices followed by single-slice multiple sampling image augmentation. Both whole tumor multislice segmentation and single-slice multiple sampling approaches were used to arrive at the best model. Radiomic features were extracted, which included first-order features, second-order (GLCM—Grey level co-occurrence matrix), and shape features. Feature enrichment was done using LASSO (Least Absolute Shrinkage and Selection Operator) regression, followed by radiomic classification using Support Vector Machine (SVM) and a 10-fold cross-validation strategy for model development. The area under the Receiver Operator Characteristic (ROC) curve and predictive accuracy were used as diagnostic metrics to evaluate the model to classify IDH mutant and wild-type subgroups.ResultsMultislice analysis resulted in a better model compared to the single-slice multiple-sampling approach. A total of 164 MR-based texture features were extracted, out of which LASSO regression identified 14 distinctive GLCM features for the endpoint, which were used for further model development. The best model was achieved by using combined T1C and T2W MR images using a Quadratic Support Vector Machine Classifier and a 10-fold internal cross-validation approach, which demonstrated a predictive accuracy of 89% with an AUC of 0.89 for each IDH mutant and IDH wild subgroup.ConclusionA machine learning classifier of radiomic features extracted from multiparametric MRI images (T1C and T2w) provides important diagnostic information for the non-invasive prediction of the IDH mutant or wild-type phenotype of high-grade gliomas and may have potential use in either escalating or de-escalating adjuvant therapy for gliomas or for using targeted agents in the future.

Intraoperative imaging has become one of the most important adjuncts in neurosurgery, especially in the surgical treatment of intra-axial tumors. Navigation and intraoperative magnetic resonance imaging have limitations, and intraoperative ultrasonography (IOUS) has emerged as a versatile and multifaceted alternative. With technological advances in ultrasound scanners and newer multifunctional probes, the potential of IOUS is increasingly being utilized in the resection of tumors. The addition of image guidance to IOUS has exponentially increased the power of this technique. Navigated ultrasonography (nUS) can now overcome many of the limitations of conventional standalone two-dimensional ultrasonography. In this pictorial essay, we outline our nUS technique (both two- and three-dimensional) for the resection of intra-axial tumors with illustrated examples highlighting the various steps and corresponding benefits of the technique.

Background: Sinonasal tumors are a rare group of neoplasms with limited data available regarding their treatment. Objectives: To estimate the 5 year outcomes and late adverse events of locally advanced sinonasal tumors treated with neoadjuvant therapy (NACT) followed by local therapy. Methods: Twenty-five patients with locally advanced esthesioneuroblastoma or sinonasal neuroendocrine tumors treated between August 2010 and August 2014 with NACT followed by local therapy were selected. The 5-year outcome and late adverse events (CTCAE version 4.02) were noted. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. COX regression analysis was used to identify factors impacting PFS and OS. Results: The median follow-up was 5.15 years. The 5-year PFS in the esthesioneuroblastoma cohort and in the sinonasal neuroendocrine carcinoma (SNEC) cohort was 63.5% (95% confidence interval [CI]: 28.9–84.7) and 34.6% (95% CI: 10.1–61.1), respectively (P = 0.1). The only factor impacting PFS on multivariate analysis was a response to NACT (P = 0.033). The 5-year OS in the esthesioneuroblastoma cohort and in the SNEC cohort was 91.7% (95% CI: 53.9–98.9) and 46.2% (95% CI: 19.2–69.6), respectively (P = 0.024). Any grade late adverse events were seen in 20 patients (80%). Metabolic late adverse events were seen in 19 patients (76%). Conclusion: NACT in advanced sinonasal cancers is associated with an improvement in 5-year outcomes. However, late side effects, especially metabolic, are seen in these patients and should be evaluated during follow-up.

Purpose A semantic feature-based reporting proforma for intraoperative ultrasound findings in brain tumors was devised to standardize reporting. It was applied as a pilot study on a cohort of histologically confirmed high-grade supratentorial gliomas (Grade 3 and 4) for internal validation. Materials and Methods This intraoperative semantic ultrasound proforma was used to evaluate 3D ultrasound volumes using Radiant DICOM software by 3 surgeons. The ultrasound semantic features were correlated with histological features like tumor grade, IDH status, and MIB index. Results 68 patients were analyzed using the semantic proforma. Irregular crenated was the most common margin (63.2%) and lesions were heterogeneously hyperechoic (95.6%). Necrosis was commonly seen and noted as single (67.6%) or multiple (13.2%) in over 80% cases. A separate perilesional zone, which was predominantly hyperechoic in 41.8% and both hypo and hyperechoic in 12.7%, could be identified in 54.5% of cases. Grade 4 tumors were more likely to have an irregular crenated margin (71.2%) with a single large area of necrosis, while Grade 3 tumors were likely to have smooth (31.3%) or non-characterizable margins (31.2%) with no or multiple areas of necrosis. IDH-negative tumors were more likely to have a single large focus of necrosis. Among the GBMs (52 cases), MIB labelling index of>15% was associated with poorly delineated, uncharacterizable margins, when compared with MIB labelling index

Purpose Non-enhancing diffuse gliomas are a challenging surgical proposition. Delineation of tumor extent on preoperative imaging and intraoperative visualization are often difficult. Methods We retrospectively analyzed all cases of non-enhancing gliomas that were operated on using navigated 3-dimensional ultrasonography (US). tumor delineation (good, moderate, or poor) on preoperative magnetic resonance imaging (MRI) and intraoperative US was compared. Post-resection US findings with respect to residual tumor status were compared to the postoperative imaging findings. The extent of resection was calculated and recorded. Results There were 55 gliomas (43 high-grade, 12 low-grade). Forty were close to eloquent areas. The pre-resection concordance of MRI with US was 56%, with US defining more tumors as well-delineated (n=26) than MRI (n=13). US was used for resection control in 50 cases. Gross tumor resection was achieved in 24 cases (51%). US correctly predicted the residual tumor status in 78% of cases. The use of US led to radical resections even in some tumors preoperatively deemed to be unresectable. However, eloquent location was the only independent predictor of the extent of resection. Conclusion Intraoperative US is a useful tool for guiding resection of non-enhancing gliomas. It may be better than MRI for delineating these tumors, and may thereby facilitate improved resection of these otherwise poorly delineated tumors. However, functional boundaries remain the main limiting factor for achieving complete resection of non-enhancing gliomas.

Abstract Genome-wide expression profiling studies have identified four core molecular subgroups of medulloblastoma: WNT, SHH, Group 3 and Group 4. Molecular markers are necessary for accurate risk stratification in the non-WNT subgroups due to the underlying heterogeneity in genetic alterations and overall survival. MiR-204 expression was evaluated in molecularly classified 260 medulloblastomas from an Indian cohort and in 763 medulloblastomas from the MAGIC cohort, SickKids, Canada. Low expression of miR-204 in the Group 3 / Group 4 tumors identify a highly aggressive subset of tumors having poor overall survival, in the two independent cohorts of medulloblastomas. Downregulation of miR-204 expression correlates with poor survival within the Group 4 as well indicating it as a valuable risk-stratification marker in the subgroup. Restoration of miR-204 expression in multiple medulloblastoma cell lines was found to inhibit their anchorage-independent growth, invasion potential and tumorigenicity. IGF2R was identified as a novel target of miR-204. MiR-204 expression resulted in downregulation of both M6PR and IGF2R that transport lysosomal proteases from the Golgi apparatus to the lysosomes. Consistent with this finding, miR-204 expression resulted in reduction in the levels of the lysosomal proteases in medulloblastoma cells. MiR-204 expression also resulted in inhibition of autophagy that is known to be dependent on the lysosomal degradation pathway and LC3B, a known miR-204 target. Treatment with HDAC inhibitors resulted in upregulation of miR-204 expression in medulloblastoma cells, suggesting therapeutic role for these inhibitors in the treatment of medulloblastomas. In summary, miR-204 is not only a valuable risk stratification marker in the combined cohort of Group 3 / Group 4 medulloblastomas as well as in the Group 4 itself, that has paucity of good prognostication markers, but also has therapeutic potential as indicated by its tumor suppressive effect on medulloblastoma cells.

The emergence of omics technologies over the last decade has helped in advancement of research and our understanding of complex diseases like brain cancers. However, barring genomics, no other omics technology has been able to find utility in clinical settings. The recent advancements in mass spectrometry instrumentation have resulted in proteomics technologies becoming more sensitive and reliable. Targeted proteomics, a relatively new branch of mass spectrometry-based proteomics has shown immense potential in addressing the shortcomings of the standard molecular biology-based techniques like Western blotting and Immunohistochemistry. In this study we demonstrate the utility of Multiple reaction monitoring (MRM), a targeted proteomics approach, in quantifying peptides from proteins like Apolipoprotein A1 (APOA1), Apolipoprotein E (APOE), Prostaglandin H2 D-Isomerase (PTGDS), Vitronectin (VTN) and Complement C3 (C3) in cerebrospinal fluid (CSF) collected from Glioma and Meningioma patients. Additionally, we also report transitions for peptides from proteins – Vimentin (VIM), Cystatin-C (CST3) and Clusterin (CLU) in surgically resected Meningioma tissues; Annexin A1 (ANXA1), Superoxide dismutase (SOD2) and VIM in surgically resected Glioma tissues; and Microtubule associated protein-2 (MAP-2), Splicing factor 3B subunit 2 (SF3B2) and VIM in surgically resected Medulloblastoma tissues. To our knowledge, this is the first study reporting the use of MRM to validate proteins from three types of brain malignancies and two different bio-specimens. Future studies involving a large cohort of samples aimed at accurately detecting and quantifying peptides of proteins with roles in brain malignancies could potentially result in a panel of proteins showing ability to classify and grade tumors. Successful application of these techniques could ultimately offer alternative strategies with increased accuracy, sensitivity and lower turnaround time making them translatable to the clinics.

Meningiomas are one of the most prevalent primary brain tumors. Our study aims to obtain mechanistic insights of meningioma pathobiology using mass spectrometry-based label-free quantitative proteome analysis to identifying druggable targets and perturbed pathways for therapeutic intervention. Label-free based proteomics study was done from peptide samples of 21 patients and 8 non-tumor controls which were followed up with Phosphoproteomics to identify the kinases and phosphorylated components of the perturbed pathways. In silico approaches revealed perturbations in extracellular matrix remodeling and associated cascades. To assess the extent of influence of Integrin and PI3K-Akt pathways, we used an Integrin Linked Kinase inhibitor on patient-derived meningioma cell line and performed a transcriptomic analysis of the components. Furthermore, we designed a Targeted proteomics assay which to the best of our knowledge for very first-time enables identification of peptides from 54 meningioma patients via SRM assay to validate the key proteins emerging from our study. This resulted in the identification of peptides from CLIC1, ES8L2, and AHNK many of which are receptors and kinases and are difficult to be characterized using conventional approaches. Furthermore, we were also able to monitor transitions for proteins like NEK9 and CKAP4 which have been reported to be associated with meningioma pathobiology. We believe, this study can aid in designing peptide-based validation assays for meningioma patients as well as IHC studies for clinical applications.

Aim: To prospectively assess the clinical utility of pretreatment flouro-deoxy-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in patients with primary central nervous system (CNS) lymphoma (PCNSL). Materials & methods: Patients with suspected/proven PCNSL underwent baseline whole-body 18F-FDG-PET/CT. Maximum standardized uptake value and tumor/normal tissue ratios were compared between CNS lymphoma and other histological diagnoses. Results: The mean maximum standardized uptake value (27.5 vs 18.2; p = 0.001) and mean tumor/normal tissue ratio (2.34 vs 1.53; p

Background: Imaging features may be reflective of inherent disease biology and serve as potentially useful biomarkers in primary brain tumors. This study aimed to correlate conventional magnetic resonance imaging (MRI) features with O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation status and survival in glioblastoma. Methods: Conventional semantic imaging features were systematically extracted from preoperative MRI of 34 patients with glioblastoma by two reviewers independently and correlated with MGMT methylation status and survival using appropriate statistical tests. Results: MGMT promoter was methylated in 10 (30%) patients, unmethylated in 15 (44%) patients, and invalid or uninterpretable in 9 (26%) patients. Four imaging features, such as border, edema, contact with subventricular zone (SVZ), and necrosis, showed borderline correlation with methylation status. On multivariate logistic regression analysis, the odds of having methylated tumor were significantly reduced for tumors in contact with SVZ and borderline reduced for tumors with sharp borders. With a median follow-up of 18 months (interquartile range, 13–33 months), the median progression-free survival (PFS) and overall survival (OS) were 12.1 months (95% confidence interval [CI]: 9.9–14.3 months) and 17.1 months (95% CI: 12.6–21.5 months), respectively, for the study cohort. Among the semantic imaging features extracted from conventional MRI, only perilesional edema correlated significantly with PFS as well as OS. The hazards of both progression and death were significantly increased for tumors with moderate-to-severe edema on Cox regression analysis. Conclusion: Contact with SVZ and sharp tumor borders shows weak negative correlation with MGMT promoter methylation status in glioblastoma. Among all MRI features investigated in this work, moderate-to-severe edema is the only imaging feature that independently correlates with significantly inferior survival.

The influence of an aromatic hydrazide derivative, 2-(3,4,5-trimethoxybenzylidene) hydrazinecarbothioamide (TMBHC) as corrosion inhibitor on mild steel in 1 M hydrochloric acid was studied by Tafel polarization and electrochemical impedance spectroscopy (EIS) technique. The results showed that the inhibition efficiency (% IE) of TMBHC increased with increasing inhibitor concentrations and also with increase in temperatures. TMBHC acted as a mixed type of inhibitor and its adsorption on mild steel surface was found to follow Langmuir’s adsorption isotherm. The evaluation of thermodynamic and activation parameters indicated that the adsorption of TMBHC takes place through chemisorption. The formation of protective film was further confirmed by scanning electron microscopy (SEM).

Introduction: Hemangioblastomas (HBs) are rare WHO grade I neoplasms of uncertain histogenesis. Most are sporadic and association with von Hippel-Lindau disease (VHL) is uncommon. Materials and Methods: Histomorphological and immunohistochemical evaluation of 24 cases of HBs was done. Results: Age range was 15-68 yrs (median: 30 yrs) with male:Female of 1.2:1 (M-13; F-11). Cerebellum was commonest location (n = 20), one each was seen in brain stem, cervical spinal cord, fourth ventricle and frontal lobe, respectively. VHL association was noted in 5 cases. Four cases were recurrent in nature of which 3 were in association with vHL. Histologically, reticular variant was the predominant subtype (n = 15), 5 were of cellular variant and 4 were mixed. Nuclear pleomorphism, nuclear cytoplasmic inclusions, cytoplasmic vacuolation were noted in the stromal cells in varying proportions. Immunohistochemical evaluation was successful in only 11 cases and of which 8 showed stromal cell positivity for alpha-inhibin. CD56 (NCAM), Nestin and synaptophysin positivity was seen in 6, 7 and 4 cases, respectively. Nestin positivity was noted in stromal cells only and no reactivity with the endothelial cells seen. S-100 protein and NSE positivity was seen in 8 and 10 cases, respectively. Glial fibrillary acidic protein (GFAP) showed two distinct patterns of immunoreactivity - scattered stromal cell positivity (n:5) and pattern of reactive astrogliosis positivity (n:10). CD44 positivity was noted in 5 cases. VEGF and EGFR positivity was seen in 5 cases each. None of the cases showed positivity for epithelial membrane antigen and no stromal cells in any of the cases showed positivity for CD34 and CD31. Conclusion: HBs can occur in throughout the neuroaxis. Cerebellum is the commonest site of occurrence for HBs and uncommonly can occur in the supratentorial compartment and spinal cord. Its association with vHL is uncommon and no histological or immunohistochemical correlation was identified with the same.

FUNDAMENTO: Estudar o suprimento arterial do sistema condutor e sua correlação com a dominância das artérias coronárias em população do sul da Índia. OBJETIVO: Determinar angiograficamente as origens da artéria do nó sinoatrial (AnSA) e artéria do nó atrioventricular (AnAV) em indianos. MÉTODOS: O ESTudo incluiu 300 pacientes consecutivos (114 do sexo feminino e 186 do sexo masculino; idade média, 55 anos), habitantes da região costeira ao sul da Índia, submetidos a cineangiocoronariografia devido a sintomas como dor no peito, angina pectoris ou teste ergométrico positivo. As angiografias incluíram ambas as artérias coronárias (direita e esquerda) em posição oblíqua anterior direita e esquerda. A origem da AnSA e AnAV a partir das artérias coronárias foi observada e correlacionada à dominância arterial. RESULTADOS: O nó SA (sinoatrial) recebeu suprimento pela artéria coronária direita (ACD) em 53% dos casos, pelo ramo circunflexo (Cx) da artéria coronária esquerda (ACE) em 42,66% dos casos, e em 4,33% dos casos esse nó foi irrigado por ambas as artérias coronárias. O nó AV (atrioventricular) também recebeu suprimento sanguíneo com mais frequência da ACD (72,33% dos casos) do que do ramo Cx da ACE (27,66%). Surpreendentemente, em nenhum caso este nó recebeu suprimento de ambas as artérias coronárias. CONCLUSÃO: Os Resultados do presente estudo podem auxiliar os cirurgiões cardíacos, sobretudo em cirurgias relacionadas a valvopatias, devido à franca proximidade entre os ramos nodais e o complexo valvar.FUNDAMENTO: Estudiar el suministro arterial del sistema conductor y su correlación con la dominancia de las arterias coronarias en población del Sur de la India. OBJETIVO: Determinar angiográficamente los orígenes de la arteria del nódulo sinusal (AnSA) y la arteria del nódulo atrioventricular (AnAV) en indios. MÉTODOS: El estudio incluyó 300 pacientes consecutivos (114 del sexo femenino y 186 del sexo masculino; edad promedio, 55 años), habitantes de la región costera al Sur de la India, sometidos a cineangiocoronariografía debido a síntomas como dolor en el pecho, angina pectoris o test ergométrico positivo. Las angiografías incluyeron ambas arterias coronarias (derecha e izquierda) en posición oblicua anterior derecha e izquierda. El origen de la AnSA y AnAV a partir de las arterias coronarias se observó y se correlacionó con la dominancia arterial. RESULTADOS: El nódulo SA (sinusal) recibió suministro por la arteria coronaria derecha (ACD) en el 53% de los casos, por la rama circunfleja (Cx) de la arteria coronaria izquierda (ACI) en el 42,66% de los casos, y en el 4,33% de los casos este nódulo fue irrigado por ambas arterias coronarias. El nódulo AV (atrioventricular) también recibió suministro sanguíneo con más frecuencia de la ACD (72,33% de los casos) que la rama Cx de la ACI (27,66%). Sorprendentemente, en ningún caso este nódulo recibió suministro de ambas arterias coronarias. CONCLUSIÓN: Los resultados del presente estudio pueden auxiliar a los cirujanos cardíacos, sobre todo en cirugías relacionadas a valvulopatías, debido a la franca proximidad entre las ramas nodales y el complejo valvular.BACKGROUND: To study the arterial supply of the conducting system and its correlation with the dominance of the coronary arteries in the South Indian population. OBJECTIVE: To determine angiographically the origins of the sinoatrial nodal artery (SAna) and atrioventricular nodal artery (AVna) in Indians. METHODS: The study included 300 consecutive patients (114 females, 186 males; mean age, 55 years) living in the southern coastal region of India, who underwent coronary angiography either for the symptoms of chest pain, angina pectoris or positive Treadmill Test. The angiograms contained both coronary arteries (right and left) in the right and left anterior oblique position. The origin of SAna and AVna from the coronary arteries was observed and correlated with the arterial dominance. RESULTS: The SA (sinoatrial) node was supplied by the right coronary artery (RCA) in 53% of the cases, by the circumflex (Cx) branch of left coronary artery (LCA) in 42.66%, and by both coronary arteries in 4.33% of cases. The AV (atrioventricular) node was also more often supplied by the RCA (72.33% of cases) than by the Cx branch of the LCA (27.66%), and surprisingly in none of the cases was this node supplied by both coronary arteries. CONCLUSION: The results of the present study may help cardiac surgeons, particularly in surgeries related to certain valvular disorders, due to the proximity of the nodal branches to the valve complex.

The inhibiting effect of N-furfuryl-N'-phenyl thiourea (FPTU) on the corrosion of mild steel in aqueous solutions of 0.05 and 0.1MHCl, as well as 0.025 and 0.05 M H2SO4 has been demonstrated using the potentiodynamic polarization technique. The polarization data showed that FPTU acts as an efficient anodic inhibitor for mild steel in both acid solutions. Avery high inhibition efficiency was evidenced in both acid solutions and it was found to vary with the concentration of the inhibitor and temperature. The obtained kinetic parameters of adsorption revealed spontaneous adsorption and a strong interaction of FPTU with the mild steel surface.

OBJECTIVES: To determine the percentage and type of aortic arch variations in Indian subjects and their clinical and surgical importance and embryological basis. PATIENTS AND METHOD: In our investigation, branching patterns of the aortic arch were studied in 62 formalin-fixed cadavers of both sexes of Indian origin, aged 45-79. The dissections were carried out in formalin-preserved cadavers and the aortic arch variations were observed after exposing the thoracic and cervical region during routine dissection of undergraduate students of Indian origin in Kasturba Medical College, Mangalore. RESULTS: The usual three-branched aortic arch was found in 56 cadavers (91.4%); variations were found in six cadavers (9.6%); 4.8% presented common origin of the carotid arteries; 1.6% had bi-innominate sequence, and the same specimen had left coronary artery arising from arch of aorta directly; 1.6% presented right subclavian artery arising directly from the aorta; 1.6% had left vertebral artery a branch of aortic arch. Five out of six cadavers with anomalous aortic arch branching pattern were females. One male cadaver presented anomalous origin of left vertebral artery directly from the arch. CONCLUSION: The wide spectrum of variations in the anatomical arrangements of the aortic arch branches in the Indian population was at par with other populations of the world. Although anomalous origins of the aortic arch branches are merely anatomic variants, accurate information about them is vital for vascular surgery in the thorax, head and neck region.OBJETIVOS: Determinar a porcentagem e o tipo de variações do arco aórtico em indivíduos indianos, bem como sua importância clínica e cirúrgica e base embriológica. PACIENTES E MÉTODOS: Em nossa investigação, os padrões de ramificação do arco aórtico foram estudados em 62 cadáveres fixados em formalina de ambos os sexos, de origem indiana e com idade entre 45 e 79 anos. As dissecações foram realizadas em cadáveres preservados em formalina, e as variações do arco aórtico foram observadas após a exposição das regiões torácica e cervical durante a dissecação de rotina de alunos da graduação do Kasturba Medical College, Mangalore, Índia. RESULTADOS: O arco aórtico normal de três ramificações foi encontrado em 56 cadáveres (91,4%); as variações foram encontradas em seis cadáveres (9,6%); 4,8% apresentavam origem comum das artérias carótidas; 1,6% tinham seqüência binominada, e o mesmo espécime tinha a origem da artéria coronária esquerda diretamente no arco aórtico; 1,6% apresentavam a origem da artéria subclávia direita diretamente na aorta; 1,6% tinham como ramificação do arco aórtico uma artéria vertebral esquerda. Cinco de seis cadáveres com padrão de ramificação anômalo do arco aórtico eram do sexo feminino. Um cadáver do sexo masculino apresentou origem anômala da artéria vertebral esquerda diretamente no arco. CONCLUSÃO: O amplo espectro de variações nos padrões anatômicos das ramificações do arco aórtico na população indiana estava em concordância com outras populações mundiais. Embora as origens anômalas das ramificações do arco aórtico sejam meramente variações anatômicas, informações precisas sobre elas é essencial para a cirurgia vascular na região do tórax, cabeça e pescoço.

Acomplexometric method for the determination of mercury(II) in presence of other metal ions, based on the selective masking action of ethanethiol towards mercury(II) is described. Mercury(II) present in a given sample solution is first complexed with an excess of EDTAand the unreacted EDTAis titrated against zinc sulphate solution at pH 5–6 (hexamine buffer) using xylenol orange as the indicator. An excess of a 0.3 % solution of ethanethiol is then added to displace EDTA from the Hg(II)–EDTA complex. The released EDTAis titrated with a standard zinc sulphate solution. Reproducible and accurate results are obtained for 4–85 mg of mercury(II) with a relative error of less than ± 0.46 % and coefficient of variation of not more than 0.47 %. The effects of the presence of various ions were studied. The method can be used for the analysis of mercury in its synthetic alloy mixtures and also in complexes.

Sodium dithionite is proposed as a new demasking agent for the rapid and selective complexometric determination of thallium(III). In the presence of diverse metal ions, thallium (III) was first complexed with excess EDTA and the surplus EDTAwas then titrated with a standard zinc sulphate solution at pH 5–6 (hexamine buffer) using Xylenol Orange as the indicator. The EDTAequivalent to thallium was then released selectively with sodium dithionite and back titrated with a standard zinc sulphate solution as before. Reproducible and accurate results were obtained in the range 4–100 mg of thallium with a relative error of ±27 % and a coefficient of variation (n = 6) of not more than 0.30 %. The effects of various diverse ions were studied. The method was applied to the determination of thallium in its complexes and in alloys.

The inhibition performance and adsorption behaviour of 4-hydroxy-N′-[(E)-(1H-indole-2-ylmethylidene)] benzohydrazide (HIBH) on mild steel in 1 M HCl solution were tested by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The inhibition efficiency of HIBH increases with increase in inhibitor concentration in the temperature range 30–60°C. Polarisation curves indicate that HIBH is a mixed inhibitor, affecting both cathodic and anodic corrosion currents. The adsorption process of HIBH at the mild steel/hydrochloric acid solution interface obeyed Langmuir adsorption isotherm model and inhibition takes place by mixed adsorption, predominantly chemisorption. The activation and thermodynamic parameters for the corrosion inhibition process were calculated to elaborate the mechanism of corrosion inhibition.

The asymmetric unit of the title compound, C20H17NO4, consists of two crystallographically independent molecules. In one of the molecules, the central benzene ring forms dihedral angles of 2.26 (6) and 58.68 (6)° with the terminal benzene rings and the dihedral angle between the terminal benzene rings is 56.45 (6)°. The corresponding values for the other molecule are 35.17 (6), 70.97 (6) and 69.62 (6)°, respectively. In the crystal, an inversion dimer linked by a pair of C—H...O hydrogen bonds occurs for one of the unique molecules. C—H...π and π–π [centroid–centroid distances = 3.7113 (8) and 3.7216 (7) Å] interactions link the components into a three-dimensional network.

In the title methylbenzoate compound, C16H16O3, the molecule is essentially planar (r.m.s. of all fitted non-H atoms = 0.0370 Å); the dihedral angle between the phenyl rings is 2.30 (7)°. Apart from a C—H...π interaction, no marked intermolecular contacts are obvious.

In the title compound, C24H20BrF2N3O3S, the triazole ring (r.m.s. deviation = 0.0107 Å) makes dihedral angles of 28.18 (14), 63.76 (14) and 77.01 (18)°, respectively, with the trimethoxy-, bromo-, and difluoro-substituted benzene rings. The C atoms of the meta methoxy groups are roughly coplanar with their ring [displacements = −0.289 (4) and 0.083 (7) Å], whereas the C atom of the para group is displaced [1.117 (3) Å]. In the crystal, inversion dimers linked by two pairs of C—H...O hydrogen bonds occur. The ring motif of the two hydrogen bonds to their symmetry-generated O-atom acceptors is R22(8).

In the title compound, C24H20ClF2N3O3S, the essentially planar triazole ring (r.m.s. deviation = 0.001 Å) forms dihedral angles of 22.35 (10), 68.17 (10) and 42.01 (10)° with the mean planes of the trimethoxyphenyl, chlorophenyl and difluorophenyl rings, respectively. A weak intramolecular C—H...π interaction occurs. In the crystal, molecules are linked into sheets lying parallel to the bc plane by C—H...O and C—H...N hydrogen bonds. The crystal packing also features weak C—H...π interactions.

In the title compound, C19H24N2O3, the benzene ring forms a dihedral angle of 65.34 (7)° with the pyrazole ring. The cyclohexane ring adopts a chair conformation. In the crystal, molecules are linked into a inversion dimers by pairs of C—H...O hydrogen bonds, generating R22(22) ring motifs.

In the title compound, C17H20N2O3, the methoxyphenyl unit is disordered over two sets of sites in a 0.715 (4):0.285 (4) ratio. The pyrazole ring forms dihedral angles of 55.88 (16) and 72.6 (4)° with the benzene rings of its major and minor components, respectively. The cyclohexane ring adopts a chair conformation and its C—N bond is in an equatorial orientation. In the crystal, molecules are linked into inversion dimers by pairs of O—H...O hydrogen bonds, generating R22(8) loops.

In the title molecular salt, C11H17N2+·Cl−, the piperazin-1-ium ring adopts a chair conformation with the aromatic ring in a pseudo-equatorial orientation. The dihedral angle between the benzene ring and the mean plane of the piperazin-1-ium ring is 51.22 (6)°. In the crystal, N—H...Cl hydrogen bonds link the molecules into chains propagating in [100]. Weak C—H...π interactions also ocur.

In the title compound, C18H13BrN4O3S3, the tetrahydropyridine ring adopts a half-chair conformation with the central methylene-C atom of the NCH2CH2 unit at the flap. The dihedral angles between the tetrahydropyridine ring and the pyridine and two thiophene rings are 69.34 (13) 5.66 (13) and 68.63 (13)°, respectively, while the dihedral angle between the 1,3,4-oxadiazole and tetrahydropyridine rings is 54.76 (13)°. The molecule is stabilized by an intramolecular C—H...N interaction. In the crystal, adjacent molecules are connected via bifurcated C—H...(N,O) hydrogen bonds, forming a chain along the b axis.

In the title molecule, C25H19N3O3S3, the tetrahydropyridine ring adopts a half-chair conformation. The dihedral angle between the least-squares plane through the tetrahydropyridine ring and two thiophene and two benzene rings are 6.25 (9), 89.49 (9), 76.43 (9) and 84.93 (8)°, respectively, while the dihedral angle between the 1,3,4-oxadiazole and tetrahydropyridine rings is 81.14 (9)°. In the crystal, adjacent molecules are connected via weak C—H...N hydrogen bonds, forming a chain along the b axis.

The asymmetric unit of the title compound, C5H2Cl2N2O2, consists of two crystallographically independent molecules. The pyridine ring in each molecule is essentially planar, with maximum deviations of 0.004 (4) and 0.007 (4) Å. Short Cl...O [3.09 (3) and 3.13 (4) Å] and Cl...Cl [3.38 (12) Å] contacts were observed. No significant intermolecular interactions were observed in the crystal packing.

The molecule of the title thiadiazole derivative, C11H11N3O2S2, has a butterfly-like structure and the whole molecule is disordered with a site-occupancy ratio of 0.629 (4):0.371 (4). The molecule is disordered in such a way that the 3-methyl-4-nitrophenyl units of the major and minor components are approximately related by 180° rotation around the C—N bond axis. The dihedral angle between the 1,3,4-thiadiazole and benzene rings is 70.8 (4)° in the major component and 74.9 (6)° in the minor component. In the crystal, molecules are arranged into screw chains along the c axis. These chains are stacked along the b axis. Weak intermolecular C—H...O and C—H...π interactions and a short C...O contact [3.005 (7) Å] are present.

In the title compound, C8H8N4, the dihedral angle between the triazole ring [maximum deviation = 0.003 (1) Å] and the benzene ring is 34.57 (7)°. In the crystal, molecules are linked into sheets lying parallel to the ac plane via intermolecular N—H...N and C—H...N hydrogen bonds. Aromatic π–π [centroid–centroid distance = 3.6750 (8) Å] stacking and N—H...π interactions are also observed.

The title molecule, C11H12N2OS2, is twisted with a dihedral angle of 83.63 (12)° between the 1,3,4-thiadiazole and benzene rings. The methoxy group deviates slightly from the attached benzene ring, with a C—C—O—C torsion angle of 4.2 (4)°. In the crystal, molecules are linked by weak C—H...N interactions and stacked along the c axis.

The asymmetric unit of the title compound, C18H16N2O2, contains two independent molecules (A and B). In molecule A, the pyrazole ring is inclined at angles of 48.86 (6) and 60.80 (6)° with respect to the two phenyl rings; the corresponding angles for molecule B are 46.86 (6) and 58.63 (6)°. In the crystal, molecules of type A are linked into sheets parallel to (001) via weak C—H...O hydrogen bonds, whereas the molecules of type B are linked into chains along [010] via weak C—H...O hydrogen bonds.

In the title compound, C16H20N2O2, the pyrazole ring is essentially planar [maximum deviation = 0.008 (2) Å] and is inclined at an angle of 82.82 (10)° with respect to the phenyl ring. The crystal packing is consolidated by pairs of intermolecular C—H...O hydrogen bonds, which link the molecules into centrosymmetric dimers stacked along the a axis.

The asymmetric unit of the title compound, C7H10N2O4S, comprises of two independent molecules (A and B) which differ in the orientation of the methylsulfonyl group [C—S—C—N = 157.98 (13)° in molecule A and 6.09 (18)° in molecule B]. In the crystal structure, molecules of type A are linked into chains along the a axis by intermolecular C—H...O hydrogen bonds. The B molecules are linked to these chains by C—H...O hydrogen bonds.

The molecule of the title compound, C3H2ClN3O2, is almost planar; the dihedral angle between the imidazole ring and the nitro group is 1.7 (2)°. In the crystal structure, pairs of intermolecular C—H...O hydrogen bonds link inversion-related molecules into dimers, generating R22(10) ring motifs. The dimers are interconnected into two-dimensional networks parallel to (102) via intermolecular N—H...N hydrogen bonds. Further stabilization is provided by short intermolecular Cl...O interactions [3.142 (2) and 3.1475 (19) Å].

In the title compound, C20H18Cl2N4O8, the two pyrimidine rings are inclined at dihedral angles of 66.68 (5) and 71.91 (6)° with respect to the central benzene ring. In the crystal structure, intermolecular C—H...N hydrogen bonds link neighbouring molecules into a ribbon-like structure along the b axis. The ribbons are interconnected into a two-dimensional network parallel to the bc plane by short intermolecular Cl...Cl [3.4427 (6) Å] and Cl...O [3.1420 (9) and 3.1750 (11) Å] interactions. The crystal structure is further stabilized by intermolecular π–π interactions [centroid–centroid distance 3.4552 (8) Å] involving the pyrimidine rings.

In the title compound, C20H18Br2N4O8, the interplanar angle of the pyrimidine rings is 75.1 (2)°. The central benzene ring is inclined at interplanar angles of 66.5 (2) and 71.9 (2)° with respect to the two pyrimidine rings. In the crystal structure, adjacent molecules are connected into two-molecule-thick arrays parallel to the bc plane via short Br...Br [3.5328 (12) Å] and Br...O [3.206 (3) and 3.301 (4) Å] interactions. A weak intermolecular π–π aromatic stacking interaction [centroid–centroid distance = 3.526 (3) Å] is also observed.

In the title compound, C14H7Cl2N3O3, the dichlorophenyl and nitrophenyl rings form dihedral angles of 5.4 (2) and 4.0 (2)°, respectively, with the oxadiazole ring. The nitro group is twisted out of the attached benzene ring by a dihedral angle of 10.4 (3)°. In the crystal, molecules are linked into a chain along the a axis by C—H...N hydrogen bonds.

In the title compound, C9H6Cl2N2O, the dihedral angle between the oxadiazole and benzene rings is 1.7 (2)°. In the crystal, the molecules are linked into chains along the b axis by short intermolecular Cl...O contacts [3.019 (3) Å].

In the title compound, C14H8Cl2N2O, the dihedral angles between the plane of the oxadiazole ring and those of the benzene rings are 2.3 (1) and 9.5 (1)°. In the crystal, molecules are linked into chains along the c axis by C—H...Cl interactions. These chains are stacked along the a axis.

In the title compound, C8H10N2O2, the acetohydrazide group is almost planar, with an r.m.s. deviation of 0.028 Å. In the crystal, the molecules are linked by intermolecular C—H...O, N—H...O and N—H...N hydrogen bonds into infinite sheets lying parallel to (001). The acetohydrazide O atom accepts two N—H...O links and one C—H...O link.

In the title compound, C8H9ClN2O2, the acetohydrazide group is approximately planar, with the maximum deviation of 0.031 (2) Å. In the crystal, the molecules are linked by N—H...N, N—H...O and C—H...O hydrogen bonds, with the acetohydrazide O atom accepting two C—H...O links and one N—H...O link. This results in infinite sheets lying parallel to (100).