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61.
Glioblastoma multiforme (GBM) defies the currently practiced management of radiotherapy, chemotherapy and surgery and hence, it is associated with a high fatality rate with a median survival of 14.6 months. In our previous work investigating different tyrosine kinase inhibitors (TKIs), we established that a combination of Crizotinib and Dasatinib exerted the most potent effect on different GBM cell lines. In this work, to improve targeted therapy at the site of the tumour and avoid systemic toxicity, we exploited the enhanced permeability and retention effect by designing micellar formulations of these two TKIs. Crizotinib and Dasatinib were successfully encapsulated in poly(styrene-co-maleic acid) (SMA) micelles which were then evaluated for their physicochemical characteristics, anti-proliferative effect, mode of cell death, efficacy in spheroid models, effect on cell signalling, antiangiogenic potential and in vivo anticancer activity. Our results showed that this combination had induced a potent anti-proliferative effect in four GBM cell lines grown as a monolayer and as a spheroid. The combination was also efficacious in in vitro models of angiogenesis and vascular mimicry. In vivo data showed the enhanced activity of the micellar TKIs compared to free drugs. In conclusion, we proved that micellar formulations of Crizotinib and Dasatinib carry promising in vitro and in vivo efficacy that warrant further investigation.  相似文献   
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Li  Wentian  Lai  Kaitao  Chopra  Neha  Zheng  Zhaomin  Das  Abhirup  Diwan  Ashish D. 《European spine journal》2022,31(4):917-925
Purpose

Low back pain (LBP), a widely prevalent and costly disease around the world, is mainly caused by intervertebral disc (IVD) degeneration (IDD). Although numerous factors may trigger this degenerative process, microbiome dysbiosis has recently been implicated as one of the likely causes. However, the exact relationship between the microbiome and IDD is not well understood. This review summarizes the potential mechanisms and discusses microbiome dysbiosis’s possible influence on IDD and LBP.

Methods

Prospective literature review.

Results

Alterations in microbiome composition and host responses to the microbiota causing pathological bone development and involution, led to the concept of gut-bone marrow axis and gut-bone axis. Moreover, the concept of the gut-disc axis was also proposed to explain the microbiome’s role in IDD and LBP. According to the existing evidence, the microbiome could be an important factor for inducing and aggravating IDD through changing or regulating the outside and inside microenvironment of the IVD. Three potential mechanisms by which the gut microbiota can induce IVD and cause LBP are: (1) translocation of the bacteria across the gut epithelial barrier and into the IVD, (2) regulation of the mucosal and systemic immune system, and (3) regulation of nutrient absorption and metabolites formation at the gut epithelium and its diffusion into the IVD. Furthermore, to investigate whether IVD is initiated by pathogenic bacteria and establish the correlation between the presence of certain microbial groups with the disease in question, microbiome diversity analysis based on16S rRNA data can be used to characterise stool/blood microbiota from IVD patients.

Conclusion

Future studies on microbiome, fungi and viruses in IDD is necessary to revolutionize our thinking about their possible role in the development of IVD diseases. Furthermore, we believe that inflammation inhibition and interruption of amplification of cascade reaction in IVD by targeting the gut and IVD microbiome is worthwhile for the treatment of IDD and LBP.

Level of Evidence I

Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

  相似文献   
64.
The reaction of pyrrole or dibromopyrrole-2-trichloroacetone with various amines results in the series of novel pyrrole-2-carboxamide bearing aromatic heterocycle or aryl or alkyl groups. Synthesized molecules were evaluated for their in vitro antibacterial activities. Most of the compounds exhibited potent activity against both Gram-positive and negative pathogens.  相似文献   
65.
A huge body evidences suggest that obesity is the single great risk factor for the development of dementia. Recently, silymarin, a flavonoid, clinically in use as a hepatoprotectant, has been reported to prevent amyloid beta-induced memory impairment by reducing oxidative stress and inflammation in mice brain. However, its potential in high-fat-diet (HFD)-induced dementia has not yet been investigated. Therefore, the present study is designed to explore the role of silymarin in HFD-induced experimental dementia in mice. Morris water maze test was employed to assess learning and memory. Various biochemical estimations including brain acetylcholinerstarse activity (AchE), thiobarbituric acid-reactive species (TBARS) level, reduced glutathione level (GSH), nirate/nitrite, and myeloperoxidase (MPO) activity were measured. Serum cholesterol level was also determined. HFD significantly impaired the cognitive abilities, along with increasing brain AchE, TBARS, MPO, nitrate/nitrite, and serum cholesterol levels. Marked reduction of brain GSH levels was observed. On the contrary, silymarin significantly reversed HFD-induced cognitive deficits and the biochemical changes. The present study indicates strong potential of silymarin in HFD-induced experimental dementia.  相似文献   
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Strategy, Management and Health Policy
Large pharmaceutical companies have traditionally focused on the development of blockbuster drugs that target disease states with large patient populations. However, with large‐scale patent expirations and competition from generics and biosimilars, anemic pipelines, escalating clinical trial costs, and global health‐care reform, the blockbuster model has become less viable. Orphan drug initiatives and the incentives accompanied by these have fostered renewed research efforts in the area of rare diseases and have led to the approval of more than 400 orphan products. Despite targeting much smaller patient populations, the revenue‐generating potential of orphan drugs has been shown to be huge, with a greater return on investment than non‐orphan drugs. The success of these “niche buster” therapeutics has led to a renewed interest from “Big Pharma” in the rare disease landscape. This article reviews the key drivers for orphan drug research and development, their profitability, and issues surrounding the emergence of large pharmaceutical firms into the orphan drug space.  相似文献   
67.
U or C-shaped waveguides, coupled to analyte microchannels, have been shown to be very responsive to evanescent-wave-absorption-based sensing. However, due to only having a single C-bend length, for analyte interaction in earlier devices, there was always an opportunity to advance their evanescent-absorbance sensitivity, by including multiple C-bend structures (interfaced with the analyte microchannel system) in the device design. To achieve this objective, two different types of waveguide probes (having a different orientation of two C-bends), i.e. S-bend and spiral-bend, were theoretically analyzed and further, experimentally tested for their comparative sensitivity to evanescent wave absorption, in this pioneering study. A novel single-step fabrication procedure (using an SU-8 photoresist), was executed to fabricate these waveguide structures interfaced (both at their inner and outer bend surfaces) with a microchannel system, along with fiber-to-waveguide coupler structures. Experimentally, the sensitivity of the S-bend waveguides was found to be ∼25% higher compared to that of spiral waveguides of similar dimensions, which corroborated the results from numerical modeling. Compared to our earlier embedded C-bend waveguides, the overall evanescent-wave-absorption-based detection sensitivity of the embedded spiral and S-bend waveguides were found to be improved by ∼7.5 times and ∼9 times respectively. Finally, these devices were found to be ideally suited for more sensitive biological-, as well as, chemical-sensing applications, provided a suitable surface alteration process is performed to these waveguide probes. Further, the proposed device has a possible capability for: facile continuous (real-time) analysis, a fixed sample volume interaction, and control over the evaporation of analyte samples introduced in to the device.

The reported device is a versatile sensing-platform, with high sensitivity, for any chemical/biological-sensing applications, if suitable surface adaptation is first performed to the microchannel-system-embedded duel-bend waveguide-probe.  相似文献   
68.
BackgroundPancreatic ascites (PA) and pleural effusion (PPE) are rarely encountered in children. They develop due to disruption of the pancreatic duct (PD) or leakage from an associated pancreatic fluid collection (PFC). The literature on childhood PA/PPE and its management is scarce.MethodsA retrospective review of children with PA/PPE diagnosed and managed at our center over the last 4 years was performed. The clinical, biochemical, radiological and management profiles were analyzed. Conservative management included nil per oral, octreotide and drainage using either percutaneous catheter or repeated paracentesis. Endotherapy included endoscopic retrograde cholangiopancreatography (ERCP) and transpapillary stenting.ResultsOf the 214 children with pancreatitis, 15 (7%) had PA/PPE. Median age was 9 years with a third under 2 years. Median ascitic fluid amylase was 8840 U/L and all had elevated protein (>2.5 g/dl) and low serum ascites-albumin gradient ascites (<1.1). While PA/PPE was the first manifestation of underlying chronic pancreatitis (CP) in 10 children (67%), trauma was seen in 4 (26%) and hypertriglyceridemia in 1 (7%). On imaging, PD disruption could be identified in 10 (67%) children. ERCP and stenting was done in 10 children. Conservative management alone (n = 4) and endotherapy (n = 10) was successful in 93% with only one requiring surgery. The younger children (n = 4), were managed conservatively and only 1 of them required surgery. Resolution of PA/PPE was achieved in all with no recurrences.ConclusionsConservative management and ERCP plus transpapillary stenting results in resolution of majority of pediatric PA/PPE. Children presenting with PA/PPE needs to be evaluated for CP.  相似文献   
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