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1.
Heliyon ; 10(7): e28488, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38590861

ABSTRACT

Background: Previously, our investigations have underscored the potential of hyperthermia to improve the therapeutic efficacy of gemcitabine (GEM) in pancreatic cancer (PC). Nonetheless, the precise underlying mechanisms remain elusive. Methods: We engineered two GEM-resistant PC cell lines (BxPC-3/GEM and PANC-1/GEM) and treated them with GEM alongside hyperthermia. The impact of hyperthermia on the therapeutic potency of GEM was ascertained through MTT assay, assessment of the concentration of its active metabolite dFdCTP, and evaluation of deoxycytidine kinase (dCK) activity. Lentivirus-mediated dCK silencing was further employed to validate its involvement in mediating the GEM-sensitizing effect of hyperthermia. The mechanism underlying hyperthermia-mediated dCK activation was explored using bioinformatics analyses. The interplay between hyperthermia and the ephrin A4 (EFNA4)/ß-catenin/dCK axis was investigated, and their roles in GEM resistance was further explored via the establishment of xenograft tumor models in nude mice. Results: Hyperthermia restored dCK expression in GEM-resistant cell lines, concurrently enhancing GEM sensitivity and fostering DNA damage and cell death. These observed effects were negated by dCK silencing. Regarding the mechanism, hyperthermia activated dCK by downregulating EFNA4 expression and mitigating ß-catenin activation. Overexpression of EFNA4 activated the ß-catenin while suppressing dCK, thus diminishing cellular GEM sensitivity-a phenomenon remediated by the ß-catenin antagonist MSAB. Consistently, in vivo, hyperthermia augmented the therapeutic efficacy of GEM on xenograft tumors through modulation of the ephrin A4/ß-catenin/dCK axis. Conclusion: This study delineates the role of hyperthermia in enhancing GEM sensitivity of PC cells, primarily mediated through the suppression of the EFNA4/ß-catenin axis and activation of dCK.

2.
BMJ Open ; 13(11): e073470, 2023 11 23.
Article in English | MEDLINE | ID: mdl-37996238

ABSTRACT

INTRODUCTION: Atrial fibrillation (AF) is a major risk factor for ischaemic stroke and transient ischaemic attack (TIA), and AF detection can be challenged by asymptomatic and paroxysmal presentation. Long-term ECG monitoring after ischaemic stroke or TIA is recommended by all major societies in cardiology and cerebrovascular medicine as a secondary prophylactic measure. However, data on stroke reduction are lacking, and the recommendations show significant diversity. METHODS AND ANALYSIS: AF SPICE is a multicentre, national, investigator-initiated, randomised, parallel-group, register-based trial comparing extended ECG monitoring versus standard ECG monitoring in patients admitted with ischaemic stroke or TIA, with a composite endpoint of stroke, all-cause-mortality and intracerebral bleeding. Patients aged ≥70 years without previous AF will be randomised 1:1 to control (standard ECG monitoring) or intervention (extended ECG monitoring). In the control arm, patients will undergo 48±24 hours (ie, a range of 24-72 hours) of continuous ECG monitoring according to national recommendations. In the intervention arm, patients will undergo 14+14 days of continuous ECG monitoring 3 months apart using an ECG patch device, which will provide an easy-accessed, well-tolerated 14-day continuous ECG recording. All ECG patch recordings will be read in a core facility. In cases of AF detection, oral anticoagulation will be recommended if not contraindicated. A pilot phase has been concluded in 2022, which will transcend into the main trial during 2023-2026, including approximately 30 stroke units. The sample size was calculated to be 3262 patients. The primary outcome will be collected from register data during a 36-month follow-up. ETHICS AND DISSEMINATION: Ethical approval has been provided by the Swedish Ethical Review Authority, reference 2021-02770. The trial will be conducted according to the ethical principles of the Declaration of Helsinki and national regulatory standards. Positive results from the study have the potential for rapid dissemination in clinical practice. TRIAL REGISTRATION NUMBER: NCT05134454.


Subject(s)
Atrial Fibrillation , Brain Ischemia , Ischemic Attack, Transient , Ischemic Stroke , Stroke , Aged , Humans , Stroke/complications , Ischemic Attack, Transient/complications , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Brain Ischemia/complications , Electrocardiography , Ischemic Stroke/complications , Cerebral Hemorrhage/diagnosis , Cerebral Hemorrhage/complications , Randomized Controlled Trials as Topic , Multicenter Studies as Topic
3.
Front Oncol ; 12: 800140, 2022.
Article in English | MEDLINE | ID: mdl-35651786

ABSTRACT

Pancreatic cancer is the leading cause of cancer-related deaths worldwide, with limited treatment options and low long-term survival rates. The complex and variable signal regulation networks are one of the important reasons why it is difficult for pancreatic cancer to develop precise targeted therapy drugs. Numerous studies have associated feedback loop regulation with the development and therapeutic response of cancers including pancreatic cancer. Therefore, we review researches on the role of feedback loops in the progression of pancreatic cancer, and summarize the connection between feedback loops and several signaling pathways in pancreatic cancer, as well as recent advances in the intervention of feedback loops in pancreatic cancer treatment, highlighting the potential of capitalizing on feedback loops modulation in targeted therapy for pancreatic cancer.

4.
BMC Cancer ; 21(1): 1069, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34592939

ABSTRACT

BACKGROUND: Colorectal cancer (CRC) represents one of the major malignant cancers in the world. It has been demonstrated that long non-coding RNAs (lncRNAs) can cause great influences on various human cancers. Though MCF.2 cell line derived transforming sequence like antisense RNA 1 (MCF2L-AS1) and its carcinogenic effect in CRC has been elucidated by several previous researches, the underlying mechanism remains unknown. AIM: We aimed at exploring the function and regulatory mechanism of MCF2L-AS1 in CRC. METHODS: MCF2L-AS1 expression in CRC cells was tested via RT-qPCR assay. The effects of MCF2L-AS1 on the biological properties of CRC cells were testified through functional experiments. The molecular mechanism of MCF2L-AS1 was verified through mechanism experiments. RESULTS: MCF2L-AS1 was highly expressed in CRC cells, and it could enhance the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) process of CRC cells. MiR-105-5p was sponged by MCF2L-AS1 in CRC cells and Ras-related protein Rab-22A (RAB22A) was verified to be the downstream target of miR-105-5p. It was verified through rescue assays that RAB22A overexpression or miR-105-5p silencing could reverse the repressive impact of MCF2L-AS1 silencing on CRC progression. CONCLUSION: MCF2L-AS1 accelerated the malignant development of CRC cells by targeting the miR-105-5p/RAB22A axis.


Subject(s)
Colorectal Neoplasms/metabolism , MicroRNAs/metabolism , Neoplasm Proteins/metabolism , Rho Guanine Nucleotide Exchange Factors/metabolism , rab GTP-Binding Proteins/metabolism , Apoptosis , Cell Line, Tumor , Cell Movement , Cell Proliferation , Colorectal Neoplasms/pathology , Disease Progression , Epithelial-Mesenchymal Transition , Gene Silencing , Humans , MicroRNAs/genetics , Neoplasm Invasiveness
5.
Materials (Basel) ; 14(6)2021 Mar 12.
Article in English | MEDLINE | ID: mdl-33809379

ABSTRACT

A modern Chinese ferritic/martensitic steel SIMP, is a new perspective nuclear structural material for the spallation target in accelerator driven sub-critical system. In this work, aimed at exploring the radiation resistance properties of this material, we investigate the differences between simultaneous Fe and He ions irradiation and He implantation of SIMP steel pre-irradiated by Fe self-ions. The irradiations were performed at 300 °C. The radiation-induced hardening was evaluated by nano-indentation, while the lattice disorder was investigated by transmission electron microscopy. Clear differences were found in the material microstructure after the two kinds of the ion irradiation performed. Helium cavities were observed in the co-irradiated SIMP steel, but not the case of He implantation with Fe pre-irradiation. In the same time, the size and density of Frank loops were different in the two different irradiation conditions. The reason for the different observed lattice disorders is discussed.

6.
Front Genet ; 12: 756094, 2021.
Article in English | MEDLINE | ID: mdl-35058967

ABSTRACT

Background: Serpin peptidase inhibitor clade H, member 1 (SERPINH1) is a gene encoding a member of the serpin superfamily of serine proteinase inhibitors. The upregulated of SERPINH1 was associated with poor prognosis in breast cancer, stomach adenocarcinoma, and esophageal carcinoma. However, the role of SERPINH1 in pan-cancer is largely unexplored. Methods: SERPINH1 expression and the correlation with prognosis in human pan-cancer were analyzed by the Cancer Genome Atlas and the Genotype-Tissue Expression dataset. Pearson correlation analysis was applied to evaluate the role of SERPINH1 expression in tumor mutation burden (TMB), microsatellite instability (MSI), mismatch repair (MMR), DNA methyltransferase, and common immunoregulators. Spearman's correlation test was used to analysis SERPINH1 expression in tumor immune infiltration and infiltrating immune cells via the Tumor Immune Evaluation Resource database. Furtherly, immunohistochemistry staining of SERPINH1 was acquired from the Human Protein Atlas database for validation. Results: SERPINH1 was abnormally expressed in fourteen cancers. The high expression of SERPINH1 significantly reduced the overall survival (OS), disease-specific survival, and progression free interval in eleven cancers. Moreover, SERPINH1 expression was correlated with MMR, MSI, TMB, and DNA methylation in multiple types of cancer. Also, SERPINH1 expression showed strong association with immunoregulators and immune checkpoint markers in testicular germ cell tumors, brain lower grade glioma (LGG), pheochromocytoma and paraganglioma. In addition, SERPINH1 expression was related to immune cell infiltration in multiple cancers, particularly in breast invasive carcinoma, LGG, and liver hepatocellular carcinoma. The result of immunohistochemistry verification shown that SERPINH1 staining was higher in tumor samples than in normal tissue in colon adenocarcinoma, head and neck squamous cell carcinoma, kidney renal papillary cell carcinoma and cervical squamous cell carcinoma, which was consistent with the result of OS. Conclusion: Overall, these results indicate that SERPINH1 may serve as an important prognostic biomarker and correlate with tumor immunity in human pan-cancer.

7.
Eur J Gastroenterol Hepatol ; 32(6): 706-712, 2020 06.
Article in English | MEDLINE | ID: mdl-32317585

ABSTRACT

OBJECTIVE: The aim of the study was to investigate the clinical efficacy and safety of ketotifen for the treatment of irritable bowel syndrome with diarrhea (IBS-D). METHODS: A total of 108 enrolled IBS-D patients were randomly divided into a ketotifen group (n = 55) and a control (placebo) group (n = 53). The patients in the ketotifen group received ketotifen tablets (1 mg, oral) two times daily; patients in the control group received oral placebo for 8 weeks. Before and after 8 weeks of treatment, gastrointestinal symptoms, anorectal sensory function and the number and activity status of mast cells were assessed for both groups. RESULTS: (1) The overall effective rate of gastrointestinal symptom improvement in the ketotifen group was significantly higher than that in the control group (76.4 vs. 37.7%, P < 0.001). (2) First sensation, defecation urgency and discomfort/pain threshold in the ketotifen group improved significantly after treatment (P < 0.05); no significant changes were observed in the control group (P > 0.05). (3) In the ketotifen group, the number of mast cells in the terminal ileum decreased, and the percentages of degranulated mast cells in the sigmoid colon, ascending colon and terminal ileum decreased significantly after treatment compared with before treatment; these differences were statistically significant (P < 0.01). In the control group, the number of mast cells and the percentages of degranulated mast cells in various sites did not change significantly before and after treatment (P > 0.05). (4) Six patients (10.9%) in the ketotifen group experienced drowsiness and fatigue, but the symptoms disappeared after 1 week of treatment. CONCLUSION: Ketotifen significantly alleviated gastrointestinal symptoms and improved visceral hypersensitivity in patients with IBS-D. The therapeutic effect of ketotifen is related to a reduced number and decreased activity of mast cells in the intestinal mucosa, especially in the terminal ileum.


Subject(s)
Diarrhea/drug therapy , Gastrointestinal Agents/therapeutic use , Irritable Bowel Syndrome/drug therapy , Ketotifen/therapeutic use , Adult , Diarrhea/etiology , Female , Gastrointestinal Agents/adverse effects , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/immunology , Irritable Bowel Syndrome/complications , Ketotifen/adverse effects , Male , Mast Cells/drug effects , Mast Cells/immunology , Middle Aged , Prospective Studies , Treatment Outcome , Young Adult
8.
Saudi J Gastroenterol ; 26(3): 129-136, 2020.
Article in English | MEDLINE | ID: mdl-32270773

ABSTRACT

BACKGROUND/AIMS: The aim of this study is to evaluate serum mucin 3A (MUC3A) as a candidate biomarker for extrahepatic cholangiocarcinoma (EHCC). PATIENTS AND METHODS: 35 Patients with EHCC, 30 patients with pancreatic cancer, 35 patients with gallbladder carcinoma and 78 patients with benign biliary disease were enrolled during January 2015 to January 2016. Serum MUC3A, carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were measured in these patients. Pathology reports of patients with EHCC were collected. RESULTS: (1) The serum levels of MUC3A (87.3 ± 10.8 ng/ml) in patients with EHCC were higher than in patients with pancreatic cancer (63.2 ± 7.7 ng/ml, P < 0.001), patients with gallbladder carcinoma (59.0 ± 10.3 ng/ml, P < 0.001) and patients with benign biliary disease (56.6 ± 13.1 ng/ml, P < 0.001). (2) ROC analysis showed that using MUC3A could clearly distinguish patients with EHCC from those without EHCC with a threshold of 73.2 ng/ml. (3) According to ROC analysis, the sensitivity, specificity, and accuracy of serum MUC3A for diagnosis of EHCC were 94.3%, 89.5% and 90.4%, respectively, which were all significantly higher than CA19-9 and CEA. (4) The serum levels of MUC3A at 1 month post-operatively in 35 patients with EHCC were decreased compared to pre-operative levels (51.8 ± 5.6 vs. 87.3 ± 10.8 ng/ml, P < 0.01). (5) Compared with 20 patients with low MUC3A levels (≤88.8 ng/ml), 15 patients with high MUC3A levels (>88.8 ng/ml) had higher percentage of lymph node metastasis (66.7% vs. 25%, P = 0.014), surrounding tissue infiltration (80% vs. 30%, P = 0.003), and UICC staging IIa-III (86.7% vs. 35%, P = 0.002). CONCLUSION: The diagnostic efficiency for EHCC of MUC3A is obviously superior to CA19-9 and CEA, and a high level of serum MUC3A indicates a poor prognosis, therefore, MUC3A can be used as a potential diagnostic and prognostic biomarker for EHCC.


Subject(s)
Cholangiocarcinoma , Mucin-3 , Pancreatic Neoplasms , Biomarkers, Tumor/blood , CA-19-9 Antigen/blood , Cholangiocarcinoma/diagnosis , Humans , Lymphatic Metastasis , Mucin-3/blood , Pancreatic Neoplasms/diagnosis
9.
Eur J Gastroenterol Hepatol ; 27(4): 412-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25874514

ABSTRACT

BACKGROUND: With the popularity of endoscopic sphincterotomy (EST), long-term complications of EST are receiving increasingly more attention, but the mechanisms have not been sufficiently elucidated. AIM: This study aimed to investigate the relationship between long-term complications of EST and sphincter of Oddi (SO) function and other associated risk factors. PATIENTS AND METHODS: A total of 139 patients with choledocholithiasis who had undergone EST were consecutively enrolled, and divided into two groups: patients with long-term complications (LC group) and patients without complications (control group). Before and 2 years after EST, sphincter of Oddi manometry and bacterial culture were performed to evaluate the functional change in SO and infection of the biliary duct. RESULTS: With an average follow-up duration of 45.8 months, 25 (18.0%) patients developed long-term complications (LC group). Compared with before EST, contraction amplitude and frequency of SO in both groups were markedly reduced after EST, but the changes were not significantly different between the two groups (P>0.05). The rates of bacterial infection in the biliary tract increased significantly in the LC group compared with the control group after EST: 57.1% (12/21) versus 32.7% (35/107), respectively (P=0.034), although these were similar before EST in both the groups. Logistic regression analysis showed that cholecystolithiasis, common bile duct diameter 15 mm or more, and maximum stone diameter 15 mm or more were major risk factors for long-term complications. CONCLUSION: Weakened SO function is not a decisive factor for long-term complications of EST, which were mainly influenced by biliary tract infection and high risk factors of the biliary tract.


Subject(s)
Bacterial Infections/etiology , Choledocholithiasis/surgery , Postoperative Complications/etiology , Sphincter of Oddi/physiopathology , Sphincterotomy, Endoscopic , Adolescent , Adult , Aged , Bacterial Infections/epidemiology , Bile Duct Diseases/epidemiology , Bile Duct Diseases/etiology , Case-Control Studies , Common Bile Duct Diseases/epidemiology , Common Bile Duct Diseases/etiology , Female , Follow-Up Studies , Humans , Incidence , Logistic Models , Male , Middle Aged , Postoperative Complications/epidemiology , Prospective Studies , Risk Factors , Treatment Outcome , Young Adult
11.
Food Chem ; 141(3): 1655-60, 2013 Dec 01.
Article in English | MEDLINE | ID: mdl-23870874

ABSTRACT

Effects of 1% or 0.5% chitosan (CHI), 10% or 5% aqueous extract of ginger, onion and garlic (GOG) and their composite solutions (1% CHI+10% GOG, 0.5% CHI+5% GOG) on quality and shelf life of stewed-pork were evaluated. Microbiological (total bacterial count), chemical (pH, total volatile basic nitrogen (TVB-N), peroxide value (POV), 2-thiobarbituric acid (TBA)) and sensory characteristics were analysed periodically during refrigerated storage at 4 °C for 12 days. CHI and/or GOG treatments retarded the increases in pH, TVB-N, POV, TBA and total bacterial count. CHI showed better antibacteria but weaker antioxidation than GOG. Composite treatment had possible synergistic effect while the high concentration of composite solution (Mix1) had adverse effect on odour and overall acceptance. Mix2, the diluted solution of Mix1, could be a natural promising preservative for the stewed-pork considering the comprehensive effects of antioxidation, antibacteria and sensory quality, which could extend the shelf life for about 5-6 days.


Subject(s)
Chitosan/pharmacology , Food Preservation/methods , Food Preservatives/pharmacology , Garlic/chemistry , Meat Products/analysis , Onions/chemistry , Plant Extracts/pharmacology , Zingiber officinale/chemistry , Animals , Bacteria/drug effects , Bacteria/growth & development , Food Preservation/instrumentation , Food Storage , Humans , Lipids/chemistry , Meat Products/microbiology , Oxidation-Reduction/drug effects , Refrigeration , Swine , Taste
12.
Se Pu ; 29(10): 1041-5, 2011 Oct.
Article in Chinese | MEDLINE | ID: mdl-22268364

ABSTRACT

A reversed-phase high performance liquid chromatographic (RP-HPLC) method was developed for the determination of 17 amino acids in the pork and its broth cooked by different methods. 6-Aminoquinolyl-N-hydroxyl-succinimidyl-carbamate (AQC) was used as pre-column derivatization reagent. In the RP-HPLC method, a Nova-Pak C18 column was used with the dilution of AccQ x Tag Eluent A, acetonitrile and water as the mobile phases in a gradient elution mode. The 17 amino acids were baseline separated within 47 min with ultraviolet (UV) detection at 248 nm. Each amino acid showed good linearity in the range of 1 - 100 micromol/L except cystine (Cys2 ) in the range of 0. 5 - 50 micromol/L with the correlation coefficient (r2) more than 0. 99. The detection limits (S/N = 3) of 17 amino acids were ranged from 0. 29 to 0.96 micromol/L, and the spiked recoveries in a cooked broth sample were from 86. 5% to 101.0%. The results showed that the proposed method can be applied to determine amino acids for meat quality assessment and process optimization with simple pretreatment and good separation.


Subject(s)
Amino Acids/analysis , Chromatography, High Pressure Liquid/methods , Chromatography, Reverse-Phase/methods , Cooking/methods , Meat/analysis , Aminoquinolines/chemistry , Animals , Carbamates/chemistry , Chromatography, High Pressure Liquid/instrumentation , Swine
13.
Stem Cell Res ; 4(2): 148-54, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20089468

ABSTRACT

Neurogenesis occurs in the cerebral cortex of adult rats after focal cerebral ischemia. Whether or not the newborn neurons could synthesize neurotransmitters is unknown. To elucidate such a possibility, a photothrombotic ring stroke model with spontaneous reperfusion was induced in adult male Wistar rats. The DNA duplication marker BrdU was repeatedly injected, and the rats were sacrificed at various times after stroke. To detect BrdU nuclear incorporation and various neurotransmitters, brain sections were processed for single/double immunocytochemistry and single/double/triple immunofluorescence. Stereological cell counting was performed to assess the final cell populations. At 48 h, 5 days, 7 days, 30 days, 60 days and 90 days after stroke, numerous cells were BrdU-immunolabeled in the penumbral cortex. Some of these were doubly immunopositive to the cholinergic neuron-specific marker ChAT or GABAergic neuron-specific marker GAD. As analyzed by 3-D confocal microscopy, the neurotransmitters acetylcholine and GABA were colocalized with BrdU in the same cortical cells. In addition, GABA was colocalized with the neuron-specific marker Neu N in the BrdU triple-immunolabeled cortical cells. This study suggests that the newborn neurons are capable of synthesizing the neurotransmitters acetylcholine and GABA in the penumbral cortex, which is one of the fundamental requisites for these neurons to function in the poststroke recovery.


Subject(s)
Cerebral Cortex/metabolism , Neurogenesis/physiology , Neurotransmitter Agents/metabolism , Stroke/physiopathology , Acetylcholine/metabolism , Animals , Animals, Newborn , Bromodeoxyuridine/metabolism , Cerebral Cortex/pathology , Choline O-Acetyltransferase/metabolism , Fluorescent Antibody Technique , Glutamate Decarboxylase/metabolism , Immunohistochemistry , In Vitro Techniques , Male , Microscopy, Confocal , Neurogenesis/genetics , Rats , Rats, Wistar , gamma-Aminobutyric Acid/metabolism
14.
Stem Cell Res ; 2(1): 68-77, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19383410

ABSTRACT

Neurogenesis has been shown to occur in the cerebral cortex in adult rats after ischemic stroke. The origin of the newborn neurons is largely unknown. This study aimed to explore cell division in the poststroke penumbral cortex. Adult male Wistar rats were subjected to photothrombotic ring stroke. After repeated delivery of the DNA duplication marker BrdU, the animals were sacrificed at various times poststroke. BrdU was detected by immunohistochemistry/immunofluorescence labeling, as was the M-phase marker Phos H3 and the spindle components alpha-tubulin/gamma-tubulin. DNA damage was examined by TUNEL staining. Cell type was ascertained by double immunolabeling with the neuronal markers Map-2ab/beta-tubulin III and NeuN/Hu or the astrocyte marker GFAP. From 16h poststroke, BrdU-immunolabeled cells appeared in the penumbral cortex. From 24h, Phos H3 was colocalized with BrdU in the nuclei. Mitotic spindles immunolabeled by alpha-tubulin/gamma-tubulin appeared inside the cortical cells containing BrdU-immunopositive nuclei. Unexpectedly, the markers of neuronal differentiation, Map-2ab/beta-tubulin III/NeuN/Hu, were expressed in the Phos H3-immunolabeled cells, and NeuN was detected in some cells containing spindles. This study suggests that in response to a sublethal ischemic insult, endogenous cells with neuronal immunolabeling may duplicate their nuclear DNA and commit cell mitosis to generate daughter neurons in the penumbral cortex in adult rats.


Subject(s)
Cell Division , Cerebral Cortex/physiology , Regeneration , Stroke/pathology , Animals , Biomarkers/analysis , Cell Differentiation , Kinetics , Male , Mitosis , Neurons/chemistry , Neurons/ultrastructure , Rats , Rats, Wistar
15.
J Cereb Blood Flow Metab ; 26(7): 927-36, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16292252

ABSTRACT

This study sought to establish the photothrombotic 'ring' stroke model with late spontaneous reperfusion in adult mice. By applying a 3.0-mm diameter laser ring-beam (514 nm, 0.21 mm thick, 0.65 W/cm2) onto the exposed skull for 60 secs with concurrent erythrosin B (4.25 mg/kg) intravenous infusion for 15 secs, the centrally located cortical region within the ring locus was progressively encroached by an annular ring-shaped perfusion deficit. In this region, local cerebral blood flow (lCBF) measured by laser-Doppler flowmetry declined promptly after irradiation to 43% of the baseline value at 30 mins poststroke. Using double tracer autoradiography, quantitative lCBF measured with [14C]iodoantipyrine was 46 to 17 to 58 ml/100 g/mins at 4 h to 48 h to 7 days postischemia in this area. Cerebral protein synthesis (CPS), as detected by [3H]leucine incorporation into protein, transiently decreased to 57% to 38% to 112% at 4 h to 48 h to 7 days postischemia in the center region. Morphologically, some neurons in the center region appeared swollen at 4 h. At 48 h, the majority of neurons were severely swollen with eosinophilia and pyknosis, whereas at 7 days poststroke' the tissue morphology became partly restored. The center within the mouse photothrombotic ring lesion thus exhibits reversible alterations of local CBF, CPS and tissue morphology that are reminiscent of the cortical penumbra in other models of focal cerebral ischemia.


Subject(s)
Cerebral Cortex/blood supply , Cerebral Cortex/metabolism , Disease Models, Animal , Intracranial Thrombosis/physiopathology , Protein Biosynthesis , Stroke/physiopathology , Animals , Blood Flow Velocity/drug effects , Blood Flow Velocity/radiation effects , Carbon/administration & dosage , Carbon/pharmacokinetics , Cerebral Cortex/pathology , Cerebrovascular Circulation/drug effects , Cerebrovascular Circulation/radiation effects , Cerebrovascular Disorders/pathology , Cerebrovascular Disorders/physiopathology , Erythrosine , Intracranial Thrombosis/etiology , Intracranial Thrombosis/pathology , Lasers , Light Coagulation , Male , Mice , Mice, Inbred C57BL , Reperfusion , Reproducibility of Results , Stroke/etiology , Stroke/pathology
16.
Methods ; 30(2): 172-7, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12725784

ABSTRACT

This article describes a laser Doppler flowmetry (LDF) system that enables repeated measurements and thereby long-term followup of cortical cerebral blood flow (CBF) in awake and freely moving rats. The system consists of a specially designed flow probe adapter, a flow probe connector, and a LDF flow probe, which may thereby rotate through its own axis. During the experiment, the flow adapter is permanently mounted onto the rat's skull bone. A thin layer of skull bone is left intact at the site for cortical CBF measurements. The probe connector and the flow probe may be repeatedly detached and remounted to the adapter, which allows for cortical cerebral blood flow recording from exactly the same anatomical location. The laser Doppler flowmetry system enables stable cortical CBF recordings in the conscious rat while it moves freely in a bowl cage.


Subject(s)
Cerebral Cortex/blood supply , Cerebrovascular Circulation , Laser-Doppler Flowmetry/instrumentation , Laser-Doppler Flowmetry/methods , Animals , Consciousness , Equipment Design , Follow-Up Studies , Male , Motor Activity/physiology , Rats , Rats, Wistar , Regional Blood Flow
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