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Clustered regularly interspaced short palindromic repeat (CRISPR) system has been explored as an efficient tool for nucleic acid diagnostics. However, it normally needs instrumentation or produces turn-off signals. Herein, a bulged Y-shape DNA (Y-DNA) nanoassembly was designed and synthesized as a novel turn-on probe. A CRISPR/Cas12a and Y-DNA probe mediated colorimetric assay (named as CYMCOA) strategy was developed for visual detection of pathogen DNA. Upon activating Cas12a with pathogen DNA, the Y-DNA bulge is catalytically trans-cleaved, releasing the G-quadruplex sequence embedded in the Y-DNA nanoassembly as a peroxidase-like DNAzyme. Visible signals with chromogen substrates are thus produced. The CYMCOA strategy was combined with recombinase polymerase amplification (RPA), an isothermal amplification technique, in detecting Helicobacter pylori (Hp) bacteria and SARS-CoV-2 N plasmids as two model pathogens. The bioassay has very excellent detection sensitivity and specificity, owing to the triple cascade amplification reactions and the very low mismatch tolerance. The lower limit of detection values were 0.16 cfu⋅mL -1 , 1.5 copies⋅μL -1 , and 0.17 copies⋅μL -1 for Hp bacteria, Hp plasmids, and SARS-CoV-2 N plasmids respectively. The detection is fast and accurate. The colorimetric bioassay strategy provides to be a simple, accurate, fast and instrumentation-free platform for nucleic acids detections in various settings, including crude and emergent situations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cancer starvation/photothermal combined tumor therapy (CST/PTT) has attracted great interest attributed to their mutual compensation and synergistically enhanced effect. However, the very low O 2 supply in the tumor microenvironment (TME) greatly limits the CST efficiency of glucose oxidase (GOx). Additionally, the easy degradation in blood circulation and significant off-target effects are big challenges for clinical applications of the GOx-based CST. In this study, a drug delivery system (DDS) with specific tumor-targeted GOx delivery, near-infrared (NIR) light and TME responsive O 2 generation, NIR-responsive glucose consumption, high GOx loading, and efficient NIR photothermia was developed. Positively charged AuNRs@MnO 2 @SiO 2 nanoparticles (named AMS + NPs) were synthesized. GOx was covalently loaded with a high loading ratio of 36.0%. Finally, a thermosensitive biomimetic hybrid membrane composed of a thermosensitive lipid (TSL) membrane, red blood cell membrane (RBCM), and 4T1 cancer cell membrane (CCM) was coated on the NPs through a double-layer strategy. The AMS + -G@TSL@[RBC-CC-TSL]M NPs consumed 32.7 times glucose at 50 °C as that at 37 °C and generated 4.9 times O 2 upon NIR laser irradiation. The thermosensitive biomimetic NPs showed an efficient targeting capability to the homotypic 4T1 cancer cells/tumors accompanied by good biocompatibility, macrophage evading capability, high cancer cell cytotoxicity, and excellent antitumor efficacy. The tumor growth inhibition ratio with NIR laser irradiation reached 92.8%. The AMS + -GOx@TSL@[RBC-CC-TSL]M NPs provide a smart, efficient, safe, PTT/CST combined DDS for highly efficient tumor therapy.

A sensitive and turn-on fluorescence nanoprobe based on core-shell Ag@Au nanoparticles (Ag@AuNPs) as a fluorescence receptor and red emissive graphene quantum dots (GQDs) as a donor was fabricated. They were conjugated together through π-π stacking between the GQDs and single-strand DNA modified at the Ag@AuNPs surface. The absorption spectrum of the receptor significantly overlapped with the donor emission spectrum, leading to a strong Förster resonance energy transfer (FRET) and thus a dramatic quenching. The sensing mechanism relies on fluorescence recovery following DNA cleavage by •OH produced from Fenton-like reaction between the peroxidase-like Ag nanocore and H 2 O 2 . The red emissive feature (Ex/Em, 520 nm/560 nm) provides low background in physiological samples. The •OH production, great spectrum overlapping, and red emission together contributes to good sensitivity and living cell imaging capability. The fluorescence assay (intensity at 560 nm) achieves a low detection limit of 0.49 μM H 2 O 2 and a wide linear range from 5 to 200 μM, superior to most of the reported fluorescent probes. The RSD value for 100 μM H 2 O 2 was 1.4%. The nanoprobe exhibits excellent anti-interferences and shows low cytotoxicity. The recovery of 100 μM standard H 2 O 2 in a cancer cell lysate was 85.8%. Most satisfactorily, it can realize monitoring and imaging H 2 O 2 in living cells. This study not only presents a sensitive H 2 O 2 probe but also provides a platform for detecting other types of reactive oxygen species., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background: Development of multiple rib fractures leading to bilateral flail chest in Cronkhite-Canada Syndrome (CCS) has not been reported., Case Presentation: A 59-year-old man presented with complaints of fatigue, chest pain, respiratory distress and orthopnea requiring ventilatory support to maintain oxygenation. CCS with bilateral anterior and posterior flail chest due to multiple rib fractures (2nd-10th on the right side and 2nd-11th on the left side). He underwent open reduction and anterior and posterior internal fixation using a titanium alloy fixator and a nickel-titanium memory alloy embracing fixator for chest wall reconstruction. He recovered gradually from the ventilator and showed improvement in his symptoms. He gained about 20 kg of weight in the follow up period (6 months after discharge from the hospital)., Conclusion: CCS is a rare, complex disease that increases the risk of developing multiple rib fractures, which can be successfully treated with open reduction and internal fixation.

Background and Purpose- Intracranial artery calcification detected by computed tomography is associated with ischemic stroke as an indicator of intracranial atherosclerosis. However, little is known about its histopathology. This study aimed to explore the intracranial calcification patterns and their associations with atherosclerotic plaques. Methods- We recruited 32 adult autopsy cases to assess the calcification patterns and distributions in the middle cerebral artery, vertebral artery, and basilar artery. The relationships of calcification patterns with plaque phenotype and luminal stenosis were evaluated. The calcification patterns on computed tomography were correlated with that on histology. Results- Visible calcifications were detected within 37 (39%) segments, including 25 segments with intimal calcification, 6 segments with internal elastic lamina calcification, 3 segments with adventitial calcification, and 3 segments with concurrent calcification. Calcification occurred more often in the vertebral artery (51%), followed by the middle cerebral artery (35%) and basilar artery (14%; P<0.01 for vertebral artery versus basilar artery). Internal elastic lamina calcification was predominantly detected in the vertebral artery (7/8, 88%). All of the 27 (100%) intimal calcifications were present in the progressive atherosclerotic lesions ( P<0.001), whereas only 3/8 (38%) internal elastic lamina calcifications and 4/6 (67%) adventitial calcifications were associated with progressive plaques. Arteries with intimal calcification had more severe luminal stenosis than those without (46% versus 21%; P<0.001). Conclusions- Our histological findings indicate that the presence of intracranial artery calcification has 3 patterns, including intimal, internal elastic lamina, and adventitial calcifications. But only intimal calcification is related with progressive atherosclerotic lesions, indicative of a proxy for intracranial atherosclerosis.

Background and Purpose: Vasa vasorum (VV) have been believed to be rare or non-existent in small-caliber intracranial arteries. In a series of human cerebral artery specimens, we identified and examined the distribution of VV in association with co-existing intracranial atherosclerosis., Methods: We obtained cerebral artery specimens from 32 consecutive autopsies of subjects aged 45 years or above. We scrutinized middle cerebral artery (MCA), vertebral artery (VA), and basilar artery (BA) for the presence of adventitial VV. We described the distribution of VV, and the characteristics of co-existing atherosclerotic lesions., Results: Among 157 intracranial arteries, adventitial VV were present in 74 of the 157 specimens (47%), involving MCA (n=13, 18%), BA (n=14, 19%), and VA (n=47, 64%). Although qualitatively these 74 adventitial VV distributed similarly in arteries with or without atherosclerotic lesions (disease-free arteries n=4/8; arteries of pre-atherosclerosis n=17/42; and arteries of progressive atherosclerosis n=53/107), the presence of adventitial VV in intracranial VA was associated with a heavier plaque load (1.72±1.66 mm2 vs. 0.40±0.32 mm2, P<0.001), severer luminal stenosis (25%±21% vs. 12%±9%, P=0.002), higher rate of concentric lesions (79% vs. 36%, P=0.002), and denser intraplaque calcification (44% vs. 0%, P=0.003). Histologically, intracranial VA with VV had a larger diameter (3.40±0.79 mm vs. 2.34±0.58 mm, P<0.001), thicker arterial wall (0.31±0.13 mm vs. 0.23±0.06 mm, P=0.002), and a larger intima-media (0.19±0.09 mm vs. 0.13± 0.04 mm, P=0.003) than VA without VV., Conclusion: s Our study demonstrated the distribution of adventitial VV within brain vasculature and association between vertebral VV and progressive atherosclerotic lesions with a heavier plaque load and denser intraplaque calcification.

Background: Anterior and posterior circulation atherosclerosis differ in vascular risk factors and stroke mechanisms. However, few studies have compared the pathological features between these lesions. Using a series of intracranial artery specimens, we characterized the intracranial atherosclerotic lesions and compared pathological features among different arteries of the intracranial vasculature., Methods: Intracranial large arteries of 32 consecutively recruited autopsy cases of Chinese adults aged 45 years or older were examined pathologically using routine histology and immunostaining, to characterize the pathological features of the atherosclerotic lesions. We analyzed middle cerebral arteries (MCAs) (both left and right), vertebral arteries (VAs) (side more affected), and basilar arteries (BAs)., Results: Progressive atherosclerotic lesions were present in 91(71%) of the 128 arteries examined. Features of complicated plaques were infrequently detected: plaque hemorrhage was encountered in 12%, neovasculature in 12%, lumen thrombi in 13%, macrophage infiltration in 20%, and calcification in 25% of arteries. Luminal narrowing of MCA was the most severe, followed by VA; the BA least stenotic (37 ± 25 vs. 30 ± 24 vs. 20 ± 20%, all p  < 0.05). MCA had more eccentric (vs. concentric) plaques than VA (69 vs. 25%, p  = 0.003) and BA (69 vs. 38%; p  = 0.03). Lumen thrombi were more frequent in BA, and calcification most commonly occurred in VA atherosclerotic lesions., Conclusion: Intracranial atherosclerotic plaques were commonly present in this sample, but the lesions generally lacked features of complicated plaques. MCA lesions had demonstrable differences compared with VA and BA lesions. Further studies are needed to determine whether these characteristics indicate a distinctive atherosclerotic phenotype for the intracranial vasculature.

Background and Purpose: High signal on T1-weighted fat-suppressed images in middle cerebral artery plaques on ex vivo magnetic resonance imaging was verified to be intraplaque hemorrhage histologically. However, the underlying plaque component of low signal on T1-weighted fat-suppressed images (LST1) has never been explored. Based on our experience, we hypothesized that LST1 might indicate the presence of lipid core within intracranial plaques., Methods: 1.5 T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of bilateral middle cerebral arteries. Then middle cerebral artery specimens were removed for histology processing. LST1 presence was identified on magnetic resonance images, and lipid core areas were measured on the corresponding histology sections., Results: Total 76 middle cerebral artery locations were included for analysis. LST1 showed a high specificity (96.9%; 95% confidence interval, 82.0%-99.8%) but a low sensitivity (38.6%; 95% confidence interval, 24.7%-54.5%) for detecting lipid core of all areas. However, the sensitivity increased markedly (81.2%; 95% confidence interval, 53.7%-95.0%) when only lipid cores of area ≥0.80 mm(2) were included. Mean lipid core area was 5× larger in those with presence of LST1 than in those without (1.63±1.18 mm(2) versus 0.32±0.31 mm(2); P=0.003)., Conclusions: LST1 is a promising imaging biomarker of identifying intraplaque lipid core, which may be useful to distinguish intracranial atherosclerotic disease from other intracranial vasculopathies and to assess plaque vulnerability for risk stratification of patients with intracranial atherosclerotic disease. In vivo clinical studies are required to explore the correlation between LST1 and clinical outcomes of patients with intracranial atherosclerotic disease., (© 2016 The Authors.)

Background and Purpose: Clinical trial studies show that plaque eccentricity (symmetry) is among the plaque features that have been associated with more frequent cerebrovascular events. Plaque eccentricity of intracranial atherosclerotic disease is unclear because of lacking of cerebral artery specimens., Methods: 1.5T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of middle cerebral artery. Plaque eccentricity of histology-verified middle cerebral artery atherosclerosis was calculated on T1-weighted fat-suppressed sequence., Results: Validated by histology, concentric atherosclerotic plaques were identified in 46 middle cerebral arteries (63.9%) on magnetic resonance imaging and eccentric plaques in 26 arteries (26.1%). Eccentric plaques showed higher maximum wall thickness and lower minimum wall thickness than concentric plaques (both P<0.001). Plaque burden and brain infarctions were similar between concentric and eccentric plaques., Conclusions: Intracranial atherosclerosis presents as eccentric or concentric in geometry, which may be not linked to intracranial plaque risk. Further in vivo imaging studies are needed to identify morphological features of intracranial plaques and to verify its association with brain infarctions., (© 2015 American Heart Association, Inc.)

To examine the effects of Cerebrolysin on the treatment of diabetic peripheral neuropathy, we first established a mouse model of type 2 diabetes mellitus by administering a high-glucose, high-fat diet and a single intraperitoneal injection of streptozotocin. Mice defined as diabetic in this model were then treated with 1.80, 5.39 or 8.98 mL/kg of Cerebrolysin via intraperitoneal injections for 10 consecutive days. Our results demonstrated that the number, diameter and area of myelinated nerve fibers increased in the sciatic nerves of these mice after administration of Cerebrolysin. The results of several behavioral tests showed that Cerebrolysin dose-dependently increased the slope angle in the inclined plane test (indicating an improved ability to maintain body position), prolonged tail-flick latency and foot-licking time (indicating enhanced sensitivity to thermal and chemical pain, respectively, and reduced pain thresholds), and increased an index of sciatic nerve function in diabetic mice compared with those behavioral results in untreated diabetic mice. Taken together, the anatomical and functional results suggest that Cerebrolysin ameliorated peripheral neuropathy in a mouse model of type 2 diabetes mellitus.

Objective: Macrophage migration inhibitory factor (MIF) and CD74 emerge as important players in pathogenesis and angiogenesis of several types of malignant tumors. The purpose of this study was to evaluate the expression of MIF and CD74 in cervical squamous cell carcinoma and explore the potential roles they play in cervical tumor angiogenesis., Methods: Macrophage migration inhibitory factor and CD74 expression was assessed by immunohistochemistry in 209 cases with various degrees of cervical epithelial lesions, including 40 normal cervical epithelia, 43 mild cervical intraepithelial neoplasia 1 (CIN 1), 41 moderate-severe cervical intraepithelial neoplasia (CIN 2 to 3), and 85 cervical squamous cell carcinomas (SCCs). CD34 staining was used for counting microvessel density. Semiquantitative reverse transcription polymerase chain reaction and Western blot were used to detect messenger RNA and protein levels of MIF and CD74 in normal and malignant cervical tissues and cervical cancer cell lines SiHa and C-33A. The concentration of vascular endothelial growth factor (VEGF) in the conditioned media of cervical cancer cells was analyzed by enzyme-linked immunosorbent assay., Results: Immunohistochemical analysis showed that MIF and CD74 expression was significantly higher in CIN than in the normal samples and higher in SCC than in CIN. The overexpression of MIF was correlated with deep stromal infiltration but not with the other clinicopathologic features of SCC. Correlation analyses revealed that MIF was positively related to CD74, and both protein levels were associated with microvessel density. Exogenous MIF induced VEGF secretion in SiHa and C-33A cells in a dose-dependent manner, which can be inhibited by MIF-specific inhibitor (ISO-1) or anti-CD74 antibody., Conclusion: Overexpression of MIF and CD74 in SCC and its precancerous lesions and the up-regulation of VEGF secretion in cervical cancer cells indicate that MIF and CD74 may play critical roles in the pathogenesis and angiogenesis of cervical cancer.