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The reuse of multilayered materials, which are held together by structural epoxy adhesives, is a major challenge since the bonded substrates cannot be easily separated for recycling. In this research, we explore a one-pot strategy based on β-amino ester chemistry for the development of modified epoxy adhesives with on-demand debonding potential. For this, a formulation of commercially available acrylate, epoxy and amine compounds is used. The research starts with a systematic study, demonstrating the influence of the different compounds on the thermal and adhesive properties of the materials. Subsequently, the potential for debonding is demonstrated using rheological measurements and tensile tests. The fast, catalyst-free Aza-Michael reaction enables the straightforward preparation of such epoxy-based adhesives, while the reverse reaction allows for debonding at 120 °C. In general, a chemical design is demonstrated for producing an industrially attractive generation of debondable epoxy-based adhesives.

Background: Stereotactic biopsy of posterior fossa lesions, which are often inoperable, enables a safe trajectory and provides tissue samples for accurate diagnosis, which is crucial for correct treatment since the latest World Health Organization Classification of Tumors of the Central Nervous System from 2021 places immense emphasis on molecular diagnostics. Stereotactic biopsy using the Leksell Vantage headframe is, due to its rigid design, extremely accurate, but stiffer, making the procedure more challenging and the learning curve steeper. Methods: This retrospective analysis demonstrates the introduction of the new Leksell Vantage headframe in day-to-day practice at the University Medical Center in Maribor, Slovenia, in demanding procedures of posterior fossa biopsies, and also provides a review of the literature available on the topic with emphasis on the technical aspect of posterior fossa biopsy using the Leksell Vantage headframe in adults. Results: In the observed series of three patients with posterior fossa lesions, all biopsies were representative, despite tissue samples being small, providing conclusive histopathologic reports (glioblastoma, rosette-forming glioneuronal tumor and metastasis of melanoma) with additional molecular diagnostics. After the initial biopsy case, the preoperative planning times and procedure times were shortened as we learnt about the importance of a tailored approach from the first case. In all cases, the biopsy was performed under local anesthesia with patients being awake throughout surgery. Conclusions: The rigid Leksell Vantage headframe makes access to the posterior fossa tougher when compared to its predecessors. However, the procedure is very accurate but requires precise preoperative planning and a customized approach when placing the headframe. [ABSTRACT FROM AUTHOR]

Dental resin composites are widely used in clinical settings but often face longevity issues due to the development and accumulation of microcracks, which eventually lead to larger cracks and restoration failure. The incorporation of microcapsules into these resins has been explored to introduce self-healing capability, potentially extending the lifespan of the restorations. This study aims to enhance the performance of self-healing dental resins by optimizing the microcapsules–resin matrix physicochemical interactions. Poly(urea–formaldehyde) (PUF) microcapsules were reinforced with melamine and subsequently subjected to surface functionalization with 3-aminopropyltriethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS). Additionally, microcapsules were functionalized with a bilayer approach, incorporating tetraethyl orthosilicate (TEOS) with either APTES or MPTMS. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) confirmed an increased Si:C ratio from 0.006 to 0.165. The functionalization process did not adversely affect the structure of the microcapsules or their healing agent volume. Compared to PUF controls, the functionalized microcapsules demonstrated enhanced healing efficiency, with TEOS/MPTMS-functionalized microcapsules showing the highest performance, showing a toughness recovery of up to 35%. This work introduces a novel approach to functionalization of microcapsules by employing advanced silanizing agents such as APTES and MPTMS, and pioneering bilayer functionalization protocols through their combination with TEOS. [ABSTRACT FROM AUTHOR]

Background: The efficacy of second-line chemotherapy for patients with recurrent or progressive oligodendroglial tumors is limited. In the current study, the authors investigated the use of carboplatin as a second-line chemotherapeutic agent against these types of tumors., Methods: Twenty-three patients with recurrent or progressive oligodendrogliomas or oligoastrocytomas after first-line PCV (procarbazine, lomustine, and vincristine) chemotherapy were enrolled in a single-institution Phase II study of second-line carboplatin chemotherapy. All patients had undergone surgery, and most also had undergone conventional radiotherapy. Carboplatin was administered at a dose of 560 mg/m2 intravenously every 4 weeks. Responses were evaluated according to conventional criteria, based on magnetic resonance imaging (MRI) findings., Results: Three of 23 patients (13%) had partial responses, with neurologic improvement. Twelve patients (52%) had stable disease; in 2 of these 12 patients, a minor response was seen on MRI. Eight patients (35%) had progressive disease. The median time to tumor progression was 3 months for all patients and 9 months for patients who experienced responses to treatment. Progression-free survival rates at 6 and 12 months were 34.8% and 8.7%, respectively. Among the salvage treatment plans followed after carboplatin chemotherapy were supportive care alone, radiotherapy, third-line chemotherapy, and reoperation. The median survival duration from the start of carboplatin administration was 16 months. Myelotoxicity was severe, with Grade 3 or 4 thrombocytopenia in 60% of patients and Grade 3 or 4 neutropenia in 48% of patients., Conclusions: When administered according to a monthly schedule, carboplatin exhibited modest activity in adult patients with recurrent or progressive oligodendroglioma or oligoastrocytoma who experienced treatment failure after PCV chemotherapy; the current treatment regimen also was associated with severe toxicity. Further improvement of second-line chemotherapy for the patient group examined in the current study is necessary., (Copyright 2004 American Cancer Society.)

Non-erosive duodenitis is an ulcer-independent disorder, the pathogenesis of which is still unclear but apparently unrelated to gastric hyperacidity. However, antisecretory agents such as H2-blockers can be effective not only in relieving dyspeptic symptoms but also in promoting endoscopic healing or improvement. In this respect conflicting data are reported with cimetidine while promising, although preliminary, results were obtained with ranitidine and with nizatidine. Nizatidine seems especially effective when administered at a dose of 150 mg b.i.d., a regimen providing moderate, but continuous acid inhibition throughout a 24 hour period.

Purpose: Brain metastasis is a common, life-threatening neurological problem for patients with cancer. Single-isocenter volumetric modulated arc therapy (VMAT) has been popularly used due to its highly conformal dose and short treatment time. Accurate prediction of its dose distribution can provide a general standard for evaluating the quality of treatment plan. In this study, a deep learning model is applied to the dose prediction of a single-isocenter VMAT treatment plan for radiotherapy of multiple brain metastases. Method: A U-net with residual networks (U-ResNet) is employed for the task of dose prediction. The deep learning model is first trained from a database consisting of hundreds of historical treatment plans. The 3D dose distribution is then predicted with the input of the CT image and contours of regions of interest (ROIs). A total of 150 single-isocenter VMAT plans for multiple brain metastases are used for training and testing. The model performance is evaluated based on mean absolute error (MAE) and mean absolute differences of multiple dosimetric indexes (DIs), including (Dmax and Dmean) for OARs, (D98, D95, D50, and D2) for PTVs, homogeneity index, and conformity index. The similarity between the predicted and clinically approved plan dose distribution is also evaluated. Result: For 20 tested patients, the largest and smallest MAEs are 3.3% ± 3.6% and 1.3% ± 1.5%, respectively. The mean MAE for the 20 tested patients is 2.2% ± 0.7%. The mean absolute differences of D98, D95, D50, and D2 for PTV60, PTV52, PTV50, and PTV40 are less than 2.5%, 3.0%, 2.0%, and 3.0%, respectively. The prediction accuracy of OARs for Dmax and Dmean is within 3.2% and 1.2%, respectively. The average DSC ranges from 0.86 to 1 for all tested patients. Conclusion: U-ResNet is viable to produce accurate dose distribution that is comparable to those of the clinically approved treatment plans. The predicted results can be used to improve current treatment planning design, plan quality, efficiency, etc. [ABSTRACT FROM AUTHOR]

Breast cancer brain metastasis (BCBM) has a devastating impact on patient survival, cognitive function and quality of life. Radiotherapy remains the standard management of BM but may result in considerable neurotoxicity. Herein, we describe the current knowledge on methods for reducing radiation-induced cognitive dysfunction in patients with BCBM. A better understanding of the biology and molecular underpinnings of BCBM, as well as more sophisticated prognostic models and individualized treatment approaches, have appeared to enable more effective neuroprotection. The therapeutic armamentarium has expanded from surgery and whole-brain radiotherapy to stereotactic radiosurgery, targeted therapies and immunotherapies, used sequentially or in combination. Advances in neuroimaging have allowed more accurate screening for intracranial metastases, precise targeting of intracranial lesions and the differentiation of the effects of treatment from disease progression. The availability of numerous treatment options for patients with BCBM and multidisciplinary approaches have led to personalized treatment and improved therapeutic outcomes. Ongoing studies may define the optimal sequencing of available and emerging treatment options for patients with BCBM. [ABSTRACT FROM AUTHOR]

The present review aims to investigate the survival and functional outcomes in adult high-grade brainstem gliomas (BGSs) by comparing data from resective surgery and biopsy. MEDLINE, EMBASE and Cochrane Library were screened to conduct a systematic review of the literature, according to the PRISMA statement. Analysis was limited to articles including patients older than 18 years of age and those published from 1990 to September 2022. Case reports, review articles, meta-analyses, abstracts, reports of aggregated data, and reports on multimodal therapy where surgery was not the primary treatment were excluded. The ROBINS-I tool was applied to evaluate the risk of bias. Six studies were ultimately considered for the meta-analysis. The resective group was composed of 213 subjects and the bioptic group comprised 125. The analysis demonstrated a survival benefit in those patients in which an extensive resection was possible (STR HR 0.59 (95% CI 0.42, 0.82)) (GTR HR 0.63 (95% CI 0.43, 0.92)). Although surgical resection is associated with increased survival, the significantly higher complication rate makes it difficult to recommend surgery instead of biopsy for BSGs. Future investigations combining volumetric data and molecular profiles could add important data to better define the proper indication between resection and biopsy. [ABSTRACT FROM AUTHOR]

The results obtained in 15 patients with infections of the lower urinary tract given 500 mg cinoxacin in two daily doses for 10 days are reported. A positive response was obtained in 13 of the 15 cases. Cinoxacin is easily managed, produces no side effects and can be administered orally, all of which makes it a drug of first choice in the treatment of prophylaxis of lower urinary infections.

Background and purpose: Adult brainstem gliomas are rare primary brain tumours with heterogeneous clinical course. The low frequency of these tumours makes it difficult to achieve high-quality evidence regarding prognostic factors, adequate therapeutic approach and outcome in such patients. Methods: In this retrospective study, we analysed clinical, radiological, molecular, prognostic and therapeutic factors in a series of 47 histologically proven adult brainstem gliomas recruited over a 20-year period (1998–2018). Results: Twenty-two patients were male, 25 female with median age of 39 years. The tumour involved one brainstem segment in 20 cases and 2 or more segments in 27. Contrast enhancement was reported in 28 cases. Surgical procedures included biopsy in 26 cases and partial/total resection in the remaining 21. Histological diagnosis was of low-grade glioma in 23 patients, high-grade glioma in 22 and non-diagnostic in 2 cases. Data regarding molecular biology were available for 22 patients. Median overall survival was 35 months, in particular 16 months in high-grade glioma and 84 months in low-grade glioma. At univariate analysis, tumour grade was the only factor with a statistically significant impact on survival time (p = 0,003), whereas younger age, better performance status and total/subtotal resection showed a trend to more prolonged survival. This study also confirms safety of biopsy/surgery in adult brainstem glioma patients and shows a clear trend to a more frequent assessment of molecular biology data. Conclusions: Further prospective multicentre efforts, and hopefully clinical trials, are necessary to improve outcome in this neglected glioma patient population. [ABSTRACT FROM AUTHOR]

Gliomatosis cerebri (GC) is an aggressive glioma characterized by an invasive growth pattern and a dismal prognosis. The low incidence and non-specific symptoms at presentation pose unique challenges for early diagnosis and disease-specific research. There is no standard of care for the treatment of patients with a GC phenotype. Understanding the biology of this entity is a critical step in determining effective treatments. Toward this end, the Second International GC Group convened at National Institutes of Health, Bethesda on June 22nd-23rd 2017. This paper summarizes the main conclusions and recommendations for research priorities to fight this fatal condition. [ABSTRACT FROM AUTHOR]

Abstract: A chiral ZnII porphyrin derivative 1 and its achiral analogue 2 were studied in the solid state. Considering the rich molecular recognition of designed metalloporphyrins 1 and 2 and their tendency to crystallize, they were recrystallized from two solvent mixtures (CH2Cl2/CH3OH and CH2Cl2/hexane). As a result, four different crystalline arrangements (1 a,b and 2 a,b, from 0D to 2D) were obtained. Solid‐state studies were performed on all the species to analyze the role played by chirality, solvent mixtures, and surfaces (mica and HOPG) in the supramolecular arrangements. By means of combinations of solvents and substrates a variety of microsized species was obtained, from vesicles to flower‐shaped arrays, including geometrical microcrystals. Overall, the results emphasize the environmental susceptibility of metalloporphyrins and how this feature must be taken into account in their design. [ABSTRACT FROM AUTHOR]

Treatment of infant hypothalamic chiasmatic glioma (iCHG) is challenging, about 30% of the children progress during chemotherapy. Despite subsequent treatments the 5 year overall-survival rate is only 70%. This study investigates treatment strategies currently applied for progressive iCHG. A web-based questionnaire was sent out to the members of the SIOPE Brain Tumour Group asking for current second and third line strategies at progression during and after the end of first line therapy. The questionnaire was answered by 47 paediatric oncologists from 15 countries. iCHG progressing during first line therapy with carboplatin-vincristine would be considered for treatment with alternative chemotherapy by 17 (36%) and with surgery plus chemotherapy by 27 respondents (58%). Components suggested for second line were vinblastine (62%), cisplatin (34%) and cyclophosphamide (26%). For third line therapy bevacizumab (BVZ) was considered as suitable by respondents in 53% (often with irinotecan 40%) and vinblastine by 34% respectively. Experience with BVZ in CHG is shown by 53% of respondents regarding at least 95 patients (median treated 1-5 patients per respondent at any age) with a median BVZ administration over 12 months. Effectiveness was reported varying between stable disease and regression while complications were rarely stated (proteinuria, hypertension, bleeding). BVZ would be available to 85% of respondents as therapeutic option for iCHG patients. Multiple anti-neoplastic drug regimens are applied for progressive iCHG, partly considered in combination with surgery if safely feasible. BVZ is commonly used at a satisfactory level in third line, mainly combined with irinotecan. [ABSTRACT FROM AUTHOR]

Gliomatosis cerebri (GC) is a rare, extensively infiltrating glioma involving multiple contiguous lobes of the brain. This lethal disease affects all age groups, and the majority of patients have a poor outcome despite aggressive treatment. Despite its initial recognition in 1938, GC remains a controversial entity with little consensus in its definition, histology, or treatment. The majority of GC tumors are astrocytic, although mixed phenotypes have been identified. Treatment of GC is challenging as surgery is generally not an option due to the extensive areas of brain involved, the benefit of radiation therapy is unclear, and no chemotherapy has proven efficacy. Due to the rarity of the disease and its heterogeneity, both at histopathological and molecular levels, it is difficult to conduct clinical trials tailored for this diagnosis. This review summarizes our current knowledge, examines clinical studies focusing on the treatment of GC, highlights ongoing challenges, and discusses the recent molecular insights into adult and pediatric GC. We conclude that, although no longer recognized as a distinct pathological entity, GC represents a unique disease phenotype. Given the histologic and molecular overlap with other diffuse gliomas, the research emphasis should be on investigating its unique invasive biology. [ABSTRACT FROM AUTHOR]

Copyright of Revista Gaucha de Enfermagem is the property of Revista Gaucha de Enfermagem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chiral mesoscopic structures were obtained by Langmuir–Blodgett (LB) deposition of two tetrasteroid-porphyrins differing by the number of hydroxy groups functionalizing the steroid rings. The morphology of the porphyrin aggregates was characterized by spectroscopy (UV-Vis absorption, steady-state fluorescence, circular dichroism) and microscopy (fluorescence, scanning electrons, atomic force) techniques. Molecular Mechanics calculations were also carried out to analyze the hierarchical self-assembly process leading to the propagation of the structural properties of the tetrasteroid-porphyrin building blocks to the mesoscopic scale of the imaged chiral architectures. It has been found that, while the transfer of chiral information from the molecular to the nanoscale is determined by the winding of the tetrasteroid chains functionalizing the porphyrin scaffold, the morphology of the mesoscopic aggregates (rods or twisted ribbons) is determined by the amphiphilic (rods) or hydrophobic (ribbons) character of the outer surface of the interacting porphyrin nanostructures. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Chronicles / Epistimonika Chronika is the property of Tzaneio General Hospital and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Ependymal tumors in adults are rare, accounting for less than 4% of primary tumors of the central nervous system in this age group. The low prevalence of intracranial ependymoma in adults limits the ability to perform clinical trials. Therefore, treatment decisions are based on small, mostly retrospective studies and the role of chemotherapy has remained unclear.Methods: We performed a retrospective study on 17 adult patients diagnosed with intracranial World Health Organisation grade II or III ependymoma, who were treated with chemotherapy at any time during the disease course. Benefit from chemotherapy was estimated by applying Macdonald criteria. Progression-free (PFS) and overall survival (OS) were calculated from start of chemotherapy, using the Kaplan-Meier method.Results: Eleven patients had supratentorial and 6 infratentorial tumors. Ten patients were treated with temozolomide (TMZ), 3 with procarbazine/lomustine/vincristine (PCV), 3 with platinum-based chemotherapy and 1 patient received epirubicin/ifosfamide. Response rates were as follows: TMZ 8/10 stable disease; PCV 3/3 stable disease; platinum-based chemotherapy 1/3 partial response; epirubicin/ifosfamide 1/1 complete response. PFS rates at 6, 12 and 24 months were 52.9, 35.3 and 23.5%. OS rates at 6, 12 and 24 months were 82.4, 82.4 and 70.1%. There was no indication for a favourable prognostic role of O(6)-methylguanyl-DNA-methyltransferase (MGMT) promoter methylation which was detected in 3/12 investigated tumors.Conclusions: Survival outcomes in response to chemotherapy in adult intracranial ependymoma patients vary substantially, but individual patients may respond to any kind of chemotherapy. There were too few patients to compare survival data between chemotherapeutic subgroups. [ABSTRACT FROM AUTHOR]

Introduction: Low-grade gliomas (LGGs) are slow-growing and diffusely infiltrating tumours constituting 25-30 % of adult gliomas. Rarely, these tumours may arise in the cerebral midline, including the thalamus, hypothalamus, tectum and brainstem. Here we present a contemporary experience with midline LGGs. Methods: Midline LGGs were identified from a retrospective database of adult patients who received a histological diagnosis of WHO grade II glioma between 2006 and 2012 at a single institution. Location, radiological data and clinical outcomes were collected. IDH1 status was assessed by immunohistochemistry. Results: Eighteen patients with midline LGGs were identified, with a median age of 45. Most received biopsy upon diagnosis, though asymptomatic patients with tectal tumours underwent active surveillance. Oligodendroglial tumours were much less common than in a comparable group of lobar tumours (6 vs. 38 %, Fisher's exact test, p = 0.007). Only one tumour was immunopositive for IDH1 (1/17). Radiological diagnosis correlated with histology in only 71 % of patients. Median survival of midline LGGs was 48 months (3-90 months) and radiological features such as contrast enhancement, size and radiological diagnosis did not predict survival in this cohort. Median overall survival of midline LGGs was less than lobar LGGs (log-rank, p = 0.006), though differences became insignificant when considering only biopsied astrocytomas in both locations (log-rank, p = 0.491). Conclusions: Diagnosis of midline LGGs is complicated by both limitations of biopsy and imaging. Midline tumours have a poorer prognosis compared to lobar equivalents and survival differences are probably due to the absence of significant surgical intervention in midline locations. [ABSTRACT FROM AUTHOR]