Consensus guidelines for the management of pediatric medulloblastoma in low and middle-income countries.

The management of medulloblastoma, a pediatric brain tumor, has evolved significantly with the advent of genomic subgrouping, yet morbidity and mortality remain high in LMICs like Pakistan due to inadequate multidisciplinary care infrastructure. This paper aims to establish evidence-based guidelines tailored to the constraints of such countries. An expert panel comprising neuro-oncologists, neurosurgeons, radiologists, radiation oncologists, neuropathologists, and pediatricians collaborated to develop these guidelines, considering the specific challenges of pediatric brain tumor care in Pakistan. The recommendations cover various aspects of medulloblastoma treatment, including pre-surgical workup, neurosurgery, neuropathology, chemotherapy, radiation therapy, and supportive care. They offer both minimum required and additional optional protocols for more advanced centers, ensuring comprehensive patient management with attention to complications and complexities encountered in Pakistan. The paper's consensus guidelines strive for uniformity in healthcare delivery and address significant gaps in diagnosis, treatment, and follow-up of pediatric medulloblastoma patients.

Post-infectious Moyamoya Syndrome: A Review of Existing Scientific Literature From 2000 to 2023.

Moyamoya disease (MMD) is considered a primary disorder of an unknown etiology. In contrast, Moyamoya syndrome (MMS) refers to MMD associated with other underlying diseases, such as meningitis in childhood, neurofibromatosis type II, Down syndrome, cranial irradiation, and different types of anemias, particularly hemoglobinopathies. We aimed to provide a comprehensive clinicopathological overview of MMS. All case reports and case series published from 2000 to 2023 pertaining to MMD were included in the study. Case studies, original articles, editorials, letters to editors, and clinical images were excluded. The search was conducted using the Boolean operators ("AND" and "OR") on PubMed and Google Scholar. A total of 13 case reports and one case series study were included. The study suggests infection might be a trigger in susceptible individuals. The autoimmune antibody findings (anti-double stranded DNA IgG) suggest a potential autoimmune component in some cases. There were diverse presentations and outcomes of post-infectious MMS, with a striking predominance of pediatric cases (66.66%) and a possible female predominance. Both computerized tomography (CT) and magnetic resonance imaging (MRI) showed evidence of restricted blood flow. CT showed that stenosis, occlusion, and collateral formation were frequent vascular findings, but often unspecified in severity. Infarction, hypodensities, and hematoma were the most common parenchymal findings (22.22% each). The findings on MRI were stenosis (50%) and collateral formation (44.44%). Infarction was the most common finding (66.66%) in parenchyma. Hydrocephalus, encephalomalacia, and atrophy were less frequent. Lesions were most frequent in the internal carotid artery (66.66%), middle cerebral artery (66.66%), and anterior cerebral artery (50%). Lesions were less frequent in the posterior cerebral, vertebral, and basilar arteries. The frontal lobe (38.89%) and basal ganglia (33.33%) were commonly affected parenchymal regions. The most common risk factor was human immunodeficiency virus (HIV) infection (50%), followed by trisomy 21, cryptococcal, and other types of meningitides. Aspirin (50%) and antiretroviral therapy (38.89%) were the cornerstones of treatment for MMS. This review accentuates the noteworthy obstacles presented by post-infectious MMS, especially its catastrophic effect on children and its correlation with HIV/AIDS. According to our elaborate literature search using PubMed and Google Scholar, this is the first narrative review in the existing scientific literature summarizing the literature on post-infectious MMS.

Knowledge, Awareness and Practice of Artificial Intelligence and Types of Realities Among Healthcare Professionals: A Nationwide Survey From Pakistan.

Background Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, enabling them to perform tasks. The advancements in AI have also improved virtual reality (VR), augmented reality (AR) and mixed reality (MR) experience allowing a greater opportunity for use in the field of medicine. Objective To evaluate the knowledge, attitude and practice of AI and types of realities among Pakistani healthcare professionals (HCPs). Materials and methods This was a prospective, nationwide study designed at the Department of Neurosurgery at Punjab Institute of Neurosciences (PINS), Lahore, was conducted between January 2024 to February 2024. More than 500 HCPs were approached, out of which 176 participated in this survey consensually. A pre-formed general questionnaire based on knowledge, attitude and practices of AI and types of realities was modified according to local conditions. Google Forms (Google Inc., USA) was used to conduct the one-time sign up response. Statistical Package for Social Sciences (IBM SPSS Statistics for Windows, Version 24, USA) was used to analyze submitted responses. Results About 69.9% respondents were male HCPs. Most of the respondents were from the fields of neurosurgery, medicine and general surgery, i.e., 10.80%, 10.20% and 4%, respectively. More than 90% HCPs used Internet and electronic devices daily. A majority of 62.50% respondents agreed that AI brings benefits for the patients, while at the same time, 45.50% agreed that they would not trust the assessment of AI more than that of HCPs. 61% HCPs feared that AI-based systems could be manipulated from the outside sources, like terrorists and hackers. Although 90% respondents knew the definition of AR and VR, a strikingly low 40% respondents could only identify the practical applications of these realities when asked in a mini-quiz. About 61.40% HCPs never used any AI-based application throughout their clinical practice, but Google Health was used by 29.50% respondents, followed by Remote Patient Monitoring AI application used by 3.4% individuals. Conclusion There is an evident under-utilization of AI and types of realities in clinical practice in Pakistan. Lack of awareness, paucity of resources and conventional clinical practices are the key reasons identified. Pakistan is on the path towards the point where the developed world is currently. There is a potential to move past the initial stages of AI implementation and into more advanced modes of adopting AI and types of realities.

Odd-even effects in aryl-substituted alkanethiolate SAMs: nonsymmetrical attachment of aryl unit and its impact on the SAM structure.

Aryl-substituted alkanethiolate (AT) self-assembled monolayers (SAMs) exhibit typically so-called odd-even effects, viz. systematic variations in the film structure, packing density, and molecular inclination depending on the parity of the number of the methylene units in the alkyl linker, n. As an exception to this rule, ATs carrying an anthracen-2-yl group (Ant-n) as tail group were reported to have different behavior due the non-symmetric attachment of the anthracene unit to the AT linker, providing additional degree of freedom for the molecular organization and allowing for partial compensation of the odd-even effects. In this context, the structure of SAMs formed by adsorption of anthracene-substituted ATs (Ant-n; n = 1-6) at room temperature on Au(111) substrate was investigated by high-resolution scanning tunnelling microscopy (STM). Most of these SAMs exhibit a coexistence of two different ordered phases, some of which are common for either n = odd or n = even while other vary over the series, showing a broad variety of different structures. The average packing density of the Ant-n SAMs, derived from the analysis of the STM data, varies by 7.5-10% depending on the parity of n, being, as expected, higher for n = odd. The respective extent of the odd-even effects is noticeably lower than that usually observed for other aryl-substituted monolayers (∼25%), which goes in line with the previous findings and emphasizes the impact of the non-symmetric attachment of the aromatic unit.

Polymorphism and Building-Block-Resolved STM Imaging of Self-Assembled Monolayers of 4-Fluorobenzenemethanethiol on Au(111).

Self-assembled monolayers (SAMs) of 4-fluorobenzenemethanethiol (p-FBMT) on Au(111), prepared by immersion procedure (1 mM ethanolic solution; 60 °C; 18 h), were characterized by scanning tunneling microscopy (STM). The data suggest the formation of highly ordered monolayer with a commensurate structure, described by the 2 3 × 13 R 13 ∘ unit cell. The STM appearance of this cell occurs, however, in two different forms, with either well-localized individual spots or splitting of these spots in two components. These components are assigned to the tunneling through the entire molecule or sulfur docking group only. The respective spots correspond then to the terminal fluorine atom and sulfur docking group, manifesting, thus, building-block-resolving STM imaging. The accessibility of the docking group for direct tunneling is most likely related to a specific molecular organization for one of the two possible internal structures of the unit cell. The above results represent a showcase for potential of STM for imaging of upright-arranged and densely packed molecular assemblies, such as SAMs.

Annealing effect for self-assembled monolayers formed from terphenylethanethiol on Au(111).

The structure and morphology of self-assembled monolayers (SAMs) prepared on Au(111) from solutions of terphenylethanethiol (TP2) at room temperature and subsequently annealed at temperatures up to 473 K were investigated using scanning tunneling microscopy. This system is of particular interest because of its metastable character, holding potential for its tailored modification. Indeed, the data suggest the formation of several different structural phases, viz. α, ß, γ, and δ, appearing progressively for the as-prepared and annealed samples. The consecutive α → ß â†’ γ → δ phase transitions occurring with increasing annealing temperature involved a continuous reduction of the molecular packing density and significant changes in the substrate morphology. The major morphological changes were the appearance and progressive growth of monoatomic gold islands, on top of which the TP2 phases were formed, representing in all cases a single domain for a particular island and restricted only by the island size. For all the phases, inclined molecular orientation was assumed while a so-called lying-down arrangement, in which the TP2 backbones are orientated parallel to the gold surface, was not observed. A nearly complete desorption of the TP2 molecules was recorded at an annealing temperature of 473 K, accompanied by the drastic change in the surface morphology.

Mobility of charge carriers in self-assembled monolayers.

We present a new approach to study charge transport within 2D layers of organic semi-conductors (OSCs) using atomic force microscopy (AFM)-based lithography applied to self-assembled monolayers (SAMs), fabricated from appropriate organothiols. The extent of lateral charge transport was investigated by insulating pre-defined patches within OSC-based SAMs with regions of insulating SAM made from large band gap alkanethiolates. The new method is demonstrated using a phenyl-linked anthracenethiolate (PAT), 4-(anthracene-2-ylethynyl)benzyl thiolate. I-V characteristics of differently shaped PAT-islands were measured using the AFM tip as a top electrode. We were able to determine a relationship between island size and electrical conductivity, and from this dependence, we could obtain information on the lateral charge transport and charge carrier mobility within the thin OSC layers. Our study demonstrates that AFM nanografting of appropriately functionalized OSC molecules provides a suitable method to determine intrinsic mobilities of charge carriers in OSC thin films. In particular, this method is rather insensitive with regard to influence of grain boundaries and other defects, which hamper the application of conventional methods for the determination of mobilities in macroscopic samples.

Erratum: Cervical spine epidural abscess: a single center analytical comparison to the literature.

[This corrects the article DOI: 10.1038/scsandc.2017.36.].

Cervical spine epidural abscess: a single center analytical comparison to the literature.

STUDY DESIGN: Retrospective review of patient charts. OBJECTIVES: Cervical spine epidural abscess (CSEA) is uncommon. In this study, characteristics of CSEA patients are described through an institutional analysis and literature review. SETTING: University-affiliated city hospital. METHODS: The electronic medical record was searched from 01/2001 to 01/2012. Data on presentation, comorbidities, diagnostic modalities, pathogens, treatments, and neurological recovery were collected. RESULTS: Sixteen patients were identified with a mean age of 57.9 years (33-83). Nine were females. Common symptoms were neck/back pain (62.5%), neurological deficits (62.5%), and fever (31.3%). Comorbidities included cardiovascular disease (56.3%), renal disease (37.5%), and diabetes mellitus (37.5%). Lower levels were more likely afflicted (C5-C7). Microorganisms were commonly Staphylococcus and Streptococcus (68.8%). Eight (50.0%) received surgery (anterior [87.5%] and posterior [12.5%] cervical fusion and corpectomy [37.5%]) plus antibiotics and 8 (50.0%) were treated with antibiotics only. Patients with less comorbidities were more likely to receive surgery; more comorbidities were was associated with a poor prognosis. Eight patients (50%) made had full neurological recovery, 2 (12.5%) with had minimal recovery, 2 deaths died, and the remaining (25%) 1 was were sent to a skilled facility and 1or lost to follow-up. CONCLUSIONS: Cervical SEA can be problematic. The vast majority do not present classically and treatment does vary. It occurs more frequently in the lower cervical levels. Though antibiotics alone may suffice, surgery is frequently employed and a multitude of techniques are at the utility of the spine surgeon. Cardiovascular comorbidities are associated with a poorer outcome. In order to improve prognosis, management considerations should include both patient factors and multidisciplinary efforts.

Spanning from the West to East: An Updated Review on Endovascular Treatment of Intracranial Atherosclerotic Disease.

Ischemic stroke is a major cause of morbidity and mortality, incurring significant cost. Intracranial atherosclerotic disease (ICAD) accounts for 10-15% of ischemic stroke in Western societies, but is an underlying pathology in up to 54% of ischemic strokes in Asian populations. ICAD has largely been treated with medical management, although a few studies have examined outcomes following endovascular treatment. Our objective was to summarize the major trials that have been performed thus far in regard to the endovascular treatment of ICAD and to provide direction for future management of this disease process. Systematic review of the literature from 1966 to 2015, was conducted in regard to intracranial angioplasty and stenting. Studies were analyzed from PubMed, American Heart Association and Society of Neurointerventional Surgery databases. SAMMPRIS and VISSIT are the only randomized controlled trials from which Western guidelines of intracranial stenting have been derived, which have displayed the superiority of medical management. However, pooled reviews of smaller studies and other nonrandomized trials have shown better outcomes with endovascular therapy in select patient subsets, such as intracranial vertebrobasilar stenosis or in the presence of robust collaterals. Suboptimal cases, including longer lesions, bifurcations and significant tortuosity tend to fair better with medical management. Medical management has been shown to be more efficacious with less adverse outcomes than endovascular therapy. However, the majority of studies on endovascular management included a diverse patient population without ideal selection criteria, resulting in higher adverse outcomes. Population analyses and selective utilization of endovascular therapy have shown that the treatment may be superior to other management in select patients.

Side-Group-Induced Polymorphism in Self-Assembled Monolayers: 3,5-Bis(trifluoromethyl)benzenethiolate Films on Au(111).

The structure and molecular organization of self-assembled monolayers (SAMs) depend on a complex interplay of intermolecular and molecule-substrate interactions, so that even a small change in molecular composition can result in noticeable changes in the SAM structure. Herein we show that decoration of the most basic aromatic SAM constituent, benzenethiol, with two trifluoromethyl groups leads to distinct polymorphism in the respective SAMs, in which the appearance of a specific structural phase or a combination of several different phases is dependent on the parameters of the preparation procedure. High-quality films with a single crystallographic phase and significantly large domains could only be prepared after a short immersion time (5 min) and an additional re-immersion of the sample in pure ethanol at an elevated temperature. A standard 24 h immersion at room temperature led to poorly defined films with a large defect density and only a small portion of the surface covered by well-ordered molecular domains.

Deep Brain Stimulation for Tourette's Syndrome: The Case for Targeting the Thalamic Centromedian-Parafascicular Complex.

Tourette's syndrome (TS) is a neurologic condition characterized by both motor and phonic tics and is typically associated with psychiatric comorbidities, including obsessive-compulsive disorder/behavior and attention-deficit hyperactivity disorder, and can be psychologically and socially debilitating. It is considered a disorder of the cortico-striato-thalamo-cortical circuitry, as suggested by pathophysiology studies and therapeutic options. Among these, deep brain stimulation (DBS) of the centromedian-parafascicular nucleus (CM-Pf) of the thalamus is emerging as a valuable treatment modality for patients affected by severe, treatment-resistant TS. Here, we review the most recent experimental evidence for the pivotal role of CM-Pf in the pathophysiology of TS, discuss potential mechanisms of action that may mediate the effects of CM-Pf DBS in TS, and summarize its clinical efficacy.