Periodontitis Salivary Microbiota Aggravates Ischemic Stroke Through IL-17A.

Although epidemiological studies suggest that periodontitis is tightly associated with ischemic stroke, its impact on ischemic stroke and the underlysing mechanisms are poorly understood. Recent studies have shown that alteration in gut microbiota composition influences the outcomes of ischemic stroke. In the state of periodontitis, many oral pathogenic bacteria in the saliva are swallowed and transmitted to the gut. However, the role of periodontitis microbiota in the pathogenesis and progression of ischemic stroke is unclear. Therefore, we hypothesized that the periodontitis salivary microbiota influences the gut immune system and aggravates ischemic stroke. Mice receiving gavage of periodontitis salivary microbiota showed significantly worse stroke outcomes. And these mice also manifested more severe neuroinflammation, with higher infiltration of inflammatory cells and expression of inflammatory cytokines in the ischemic brain. More accumulation of Th17 cells and IL-17+ γδ T cells were observed in the ileum. And in Kaede transgenic mice after photoconversion. Migration of CD4+ T cells and γδ T cells from the ileum to the brain was observed after ischemic stroke in photoconverted Kaede transgenic mice. Furthermore, the worse stroke outcome was abolished in the IL-17A knockout mice. These findings suggest that periodontitis salivary microbiota increased IL-17A-producing immune cells in the gut, likely promoted the migration of these cells from the gut to the brain, and subsequently provoked neuroinflammation after ischemic stroke. These findings have revealed the role of periodontitis in ischemic stroke through the gut and provided new insights into the worse outcome of ischemic stroke coexisting with periodontitis in clinical trials.

Measurement of cerebrovascular reserve by multimodal imaging for cerebral arterial occlusion or stenosis patients: protocol of a prospective, randomized, controlled clinical study.

BACKGROUND: Cerebrovascular reactivity (CVR) is the change in cerebral blood flow in response to a vaso-active stimulus, and may assist the treatment strategy of ischemic stroke. However, previous studies reported that a therapeutic strategy for stroke mainly depends on the degree of vascular stenosis with steady-state vascular parameters (e.g., cerebral blood flow and CVR). Hence, measurement of CVR by multimodal imaging techniques may improve the treatment of ischemic stroke. METHODS/DESIGN: This is a prospective, randomized, controlled clinical trial that aimed to examine the capability of multimodal imaging techniques for the evaluation of CVR to improve treatment of patients with ischemic stroke. A total of 66 eligible patients will be recruited from Renji Hospital, Shanghai Jiaotong University School of Medicine. The patients will be categorized based on CVR into two subgroups as follows: CVR > 10% group and CVR < 10% group. The patients will be randomly assigned to medical management, percutaneous transluminal angioplasty and stenting, and intracranial and extra-cranial bypass groups in a 1:1:1 ratio. The primary endpoint is all adverse events and ipsilateral stroke recurrence at 6, 12, and 24 months after management. The secondary outcomes include the CVR, the National Institute of Health stroke scale and the Modified Rankin Scale at 6, 12, and 24 months. DISCUSSION: Measurement of cerebrovascular reserve by multimodal image is recommended by most recent studies to guide the treatment of ischemic stroke, and thus its efficacy and evaluation accuracy need to be established in randomized controlled settings. This prospective, parallel, randomized, controlled registry study, together with other ongoing studies, should present more evidence for optimal individualized accurate treatment of ischemic stroke. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ID: ChiCTR-IOR-16009635; Registered on 16 October 2016. All items are from the World Health Organization Trial Registration Data Set and registration in the Chinese Clinical Trial Registry: ChiCTR-IOR-16009635.

Intradural Transpetrosectomy for Petrous Apex Meningiomas.

OBJECTIVE: This study aimed to assess the surgical results of the intradural transpetrosectomy for petrous apex meningiomas (PAMs). In addition, we describe the methods and techniques used to expose and manage superior petrous vein and greater superficial petrosal nerve. METHODS: The authors conducted a retrospective study of 16 patients with PAMs operated by the senior author via the intradural transpetrosectomy between February 2012 to May 2017. We reviewed patient data regarding the general characteristics, surgical technique and surgery-related outcomes and adopted a combined follow-up strategy of clinic and telephone contacts to evaluate postoperative complications. RESULTS: Simpson grade I and II resection was performed in 10 out of 16 cases (62.5%), and grade III resection were reported in the remaining six cases (37.5%) with no resultant mortality. The mean Karnofsky Performance Status score was 85.6 preoperatively and improved to 91.9 postoperatively, with a mean follow-up period of 34.4 months (range, 6-66 months). Tumor recurrence was found in two patients and they underwent the second surgical operation. CONCLUSION: PAMs could be completely resected by the intradural transpetrosectomy with an improved survival rate and postoperative life quality. Superior petrous vein and greater superficial petrosal nerve should be managed properly in avoidance of postoperative complications. Finally, most meningioma inside cavernous sinus or adhered to brainstem could be totally removed without postoperative complications.

Neuroprotective effect of baicalin on focal cerebral ischemia in rats.

Baicalin, a flavonoid compound from the root of the herb Scutellaria baicalensis Georgi, has been widely used to treat patients with inflammatory disease. The aim of this study was to assess the efficacy of baicalin in a rat model of focal cerebral ischemia. Adult male Sprague-Dawley rat models of cerebral artery occlusion were established and then randomly and equally divided into three groups: ischemia (cerebral ischemia and reperfusion), valproic acid (cerebral ischemia and reperfusion + three intraperitoneal injections of valproic acid; positive control), and baicalin (cerebral ischemia and reperfusion + intraperitoneal injection of baicalin for 21 days). Neurological deficits were assessed using the postural reflex test and forelimb placing test at 3, 7, 14, and 21 days after ischemia. Rat cerebral infarct volume was measured using 2,3,5-triphenyltetrazolium chloride (TTC) staining method. Pathological change of ischemic brain tissue was assessed using hematoxylin-eosin staining. In the baicalin group, rat neurological function was obviously improved, cerebral infarct volume was obviously reduced, and the pathological impairment of ischemic brain tissue was obviously alleviated compared to the ischemia group. Cerebral infarct volume was similar in the valproic acid and baicalin groups. These findings suggest that baicalin has a neuroprotective effect on cerebral ischemia.

Ethyl Pyruvate Attenuates Early Brain Injury Following Subarachnoid Hemorrhage in the Endovascular Perforation Rabbit Model Possibly Via Anti-inflammation and Inhibition of JNK Signaling Pathway.

Early brain injury (EBI) following subarachnoid hemorrhage (SAH) is the main cause to poor outcomes of SAH patients, and early inflammation plays an important role in the acute pathophysiological events. It has been demonstrated that ethyl pyruvate (EP) has anti-inflammatory and neuroprotective effects in various critical diseases, however, the role of EP on EBI following SAH remains to be elucidated. Our study aimed to evaluate the effects of EP on EBI following SAH in the endovascular perforation rabbit model. All rabbits were randomly divided into three groups: sham, SAH + Vehicle (equal volume) and SAH + EP (30 mg/kg/day). MRI was performed to estimate the reliability of the EBI at 24 and 72 h after SAH. Neurological scores were recorded to evaluate the neurological deficit, ELISA kit was used to measure the level of tumor necrosis factor-α (TNF-α), and western blot was used to detect the expression of TNF-α, tJNK, pJNK, bax and bcl-2 at 24 and 72 h after SAH. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Fluoro-jade B (FJB) staining were used to detect neuronal apoptosis and neurodegeneration respectively, meanwhile hematoxylin and eosin (H&E) staining was used to assess the degree of vasospasm. Our results demonstrated that EP alleviated brain tissue injury (characterized by diffusion weighted imaging and T2 sequence in MRI scan), and significantly improved neurological scores at 72 h after SAH. EP decreased the level of TNF-α and downregulated pJNK/tJNK and bax/bcl-2 in cerebral cortex and hippocampus effectively both at 24 and 72 h after SAH. Furthermore, EP reduced TUNEL and FJB positive cells significantly. In conclusion, the present study supported that EP afforded neuroprotective effects possibly via reducing TNF-α expression and inhibition of the JNK signaling pathway. Therefore, EP may be a potent therapeutic agent to attenuate EBI following SAH.

[Effect of hydrogen-rich saline on blood pressure and antioxidant ability of lung tissue in scalded rats following delayed resuscitation].

OBJECTIVE: To study the effect of hydrogen-rich saline on blood pressure and antioxidant ability of lung tissue in scalded rats following delayed resuscitation. METHODS: The hydrogen-rich saline was prepared (hydrogen-saturated normal saline with hydrogen concentration of 0.6 mmol/L). Twenty SD rats were divided into hydrogen-rich saline group (HS) and normal saline group (NS) according to the random number table, with 10 rats in each group. All the rats were subjected to 30% total body surface area (TBSA) full-thickness scald. Rats in HS and NS groups were infused with hydrogen-rich saline or normal saline with one half of the total fluid replacement volume as calculated according to the Parkland formula (4 mL×kg(-1)×%TBSA(-1)) at post scald hour (PSH) 7 and one-quarter of the volume at PSH 9 and 17 respectively. The general condition of rats during the experiment was observed. The systolic pressure of rats was measured at PSH 6 and 24. All rats were sacrificed at PSH 24 to collect lung tissue for detecting superoxide dismutase (SOD) inhibition ratio and malondialdehyde (MDA) level. Data were processed with t test. RESULTS: All rats survived through the experiment. The systolic pressure of rats in HS group and NS group was respectively (87 ± 4) mm Hg (1 mm Hg = 0.133 kPa) and (86 ± 5) mm Hg at PSH 6, and the values were close (t = 0.213, P = 0.834); however the systolic pressure at 24 h was higher in HS group than in NS group [(124 ± 7) mm Hg vs. (115 ± 6) mm Hg, t = 2.958, P = 0.008]. SOD inhibition ratio of lung tissue in HS group [(0.465 ± 0.014)%] was higher than that in NS group [(0.358 ± 0.021)%, t = 11.767, P = 0.000]. MDA level of lung tissue in HS group [(922 ± 196) pmol/mg] was lower than that in NS group [(1118 ± 212) pmol/mg, t = -2.142, P = 0.046]. CONCLUSIONS: Delayed resuscitation for scalded rats with hydrogen-rich saline is helpful in the recovery of systolic pressure, and it can ameliorate lung tissue injury caused by reperfusion through enhancing the effect of antioxidase.

[Construction of dermal skeleton by double cross-linking with glutaraldehyde and ultraviolet radiation].

OBJECTIVE: To investigate the effects of preemptive freezing with different temperature and cross-linking methods on the ultrastructure of collagen membrane and its influence on human fibroblast proliferation. METHODS: Bovine collagen type I solution in concentration of 10 g/L was preliminarily frozen at -20 degrees C or - 80 degrees C for 12 hours, and lyophilized at -70 degrees C for 48 hours. The diameter of apertures in collagen membranes prepared with two different preliminary temperatures were observed by scanning electron microscope (SEM) and compared. The preliminary freezing temperature of - 80 degrees C was used for the following study. The apertures of collagen membrane performed with cross-linking glutaraldehyde and ultraviolet (UV) radiation cross-linking with glutaraldehyde (double cross - linking) after preliminary freezing were also compared. The proliferation of human fibroblasts inoculated in above cross-linking collagens were assessed by MTT assay, in terms of absorption value. RESULTS: The mean diameter of apertures of collagen membrane pre-frozen at -20 degrees C was (172 +/- 374 microm, while that at -80 degrees C was (99 +/- 24) microm. The apertures of collagen membrane were reduced in size after glutaraldehyde cross-linking, while those of double cross-linking showed no change in size. There was obvious difference in absorption value of fibroblasts 8 days after seeding between above two cross-linking methods (1.534 +/- 0.013 for glutaraldehyde cross-linking, 3.778 +/- 0.010 for double cross-linking, P < 0.05). CONCLUSION: The collagen membrane after preliminary freezing at - 80 degrees C and double cross-linking with UV radiation and glutaraldehyde may be used as a dermal skeleton substitute.