Metagenomic Next-Generation Sequencing of Cerebrospinal Fluid for the Diagnosis of Cerebral Aspergillosis.

Purpose: Cerebral aspergillosis (CA) is a rare but often fatal, difficult-to-diagnose, opportunistic infection. The utility of metagenomic next-generation sequencing (mNGS) for diagnosis of CA is unclear. We evaluated the usefulness of mNGS of the cerebrospinal fluid (CSF) for the diagnosis of CA. Methods: This prospective study involved seven consecutive patients with confirmed CA in whom CSF mNGS was performed. Serum (1→3)-ß-D-glucan and galactomannan levels were determined, and histopathological examination and mNGS of the CSF were conducted. CSF specimens from three non-infected patients were used as positive controls. Results: mNGS of the CSF was positive in six of the seven confirmed CA cases (85.71% sensitivity). In the cryptococcal meningitis group (control), mNGS of the CSF was positive for Aspergillus in two patients (84.62% specificity). The positive likelihood ratio, negative likelihood ratio, and Youden's index of mNGS for CA in the CSF were 5.565, 0.169, and 0.7, respectively. Among the six mNGS-positive cases, more than two Aspergillus species were found in four (4/6, 66.67%). In the positive controls, the addition of one A. fumigatus spore yielded a standardised species-specific read number (SDSSRN) of 25.45 by mNGS; the detection rate would be 0.98 if SDSSRN was 2. Conclusion: mNGS facilitates the diagnosis of CA and may reduce the need for cerebral biopsy in patients with suspected CA. Trial Registration Number: Chinese Clinical Trial Registry, ChiCTR1800020442.

Importance of lipid ratios for predicting intracranial atherosclerotic stenosis.

BACKGROUND: This study aims to investigate the association of lipid ratios with intracranial atherosclerotic stenosis (ICAS) in a Chinese population. METHODS: This cross-sectional study included 658 consecutive patients with ischemic stroke. Intracranial and extracranial arteries were evaluated for atherosclerotic stenosis using digital subtraction angiography or computed tomography angiography. Lipid ratios [total cholesterol (TC)/high-density lipoprotein-cholesterol (HDL-C), triglycerides (TG)/HDL-C, low-density lipoprotein-cholesterol (LDL-C)/HDL-C, non-high-density lipoprotein-cholesterol (non-HDL-C)/HDL-C, remnant cholesterol (RC)/HDL-C, apolipoprotein B (apo B)/apolipoprotein A-I (apo A-I), and apo B/HDL-C] were calculated. RESULTS: The TC/HDL-C, LDL-C/HDL-C, RC/HDL-C, non-HDL-C/HDL-C, apo B/HDL-C and apo B/apo A-I ratios (all P < 0.05) were significantly associated with ICAS but not with extracranial atherosclerotic stenosis after adjustment for confounding factors. Receiver operating characteristic (ROC) curves analysis revealed that the apo B/apo A-I ratio had the largest area under the ROC curve (AUC) among lipid levels alone and for lipid ratios (AUC = 0.588). Lipid ratios had higher AUC values than those for lipid levels alone for the identification of ICAS. CONCLUSION: The TC/HDL-C, LDL-C/HDL-C, RC/HDL-C, non-HDL-C/HDL-C apo B/HDL-C, and apo B/apo A-I ratios were significantly related to ICAS risk. Compared with the other variables tested, the apo B/apo A-I ratio appeared to be a better discriminator for identifying ICAS risk in stroke patients.

Metagenomic Next-Generation Sequencing for Diagnosis of Infectious Encephalitis and Meningitis: A Large, Prospective Case Series of 213 Patients.

Purpose: We assessed the performance of metagenomic next-generation sequencing (mNGS) in the diagnosis of infectious encephalitis and meningitis. Methods: This was a prospective multicenter study. Cerebrospinal fluid samples from patients with viral encephalitis and/or meningitis, tuberculous meningitis, bacterial meningitis, fungal meningitis, and non-central nervous system (CNS) infections were subjected to mNGS. Results: In total, 213 patients with infectious and non-infectious CNS diseases were finally enrolled from November 2016 to May 2019; the mNGS-positive detection rate of definite CNS infections was 57.0%. At a species-specific read number (SSRN) ≥2, mNGS performance in the diagnosis of definite viral encephalitis and/or meningitis was optimal (area under the curve [AUC] = 0.659, 95% confidence interval [CI] = 0.566-0.751); the positivity rate was 42.6%. At a genus-specific read number ≥1, mNGS performance in the diagnosis of tuberculous meningitis (definite or probable) was optimal (AUC=0.619, 95% CI=0.516-0.721); the positivity rate was 27.3%. At SSRNs ≥5 or 10, the diagnostic performance was optimal for definite bacterial meningitis (AUC=0.846, 95% CI = 0.711-0.981); the sensitivity was 73.3%. The sensitivities of mNGS (at SSRN ≥2) in the diagnosis of cryptococcal meningitis and cerebral aspergillosis were 76.92 and 80%, respectively. Conclusion: mNGS of cerebrospinal fluid effectively identifies pathogens causing infectious CNS diseases. mNGS should be used in conjunction with conventional microbiological testing. Trial Registration: Chinese Clinical Trial Registry, ChiCTR1800020442.

Frequency distribution of apolipoprotein E genotypes in elderly population and relationship with senile dementia.

BACKGROUND: The aim of this study was to determine the relationship between apolipoprotein E (ApoE)-ε4 genotype and senile dementia (SD) by analyzing the ApoE allelic frequency distributions among the elderly Han Chinese population. METHODS: For this purpose, a total of 316 Chongqing residents aged ≥60 years were classified as SD or control groups following the criteria of National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association. Genomic DNA was isolated from the peripheral blood lymphocytes and exon 4 of the ApoE gene with polymorphism sites was amplified by PCR and genotypes determined by restriction fragment length polymorphism (RFLP). RESULTS: We found that the most prevalent genotype was ApoE-ε3/3, followed in order by ApoE-ε3/4 and ApoE-ε2/2. The estimated ApoE allelic frequencies in individuals with SD were 0.095, 0.560, and 0.345 for ε2, ε3, and ε4, respectively. In controls, the corresponding ApoE allelic frequencies were 0.146, 0.699, and 0.155. The percentage of ε4 allele carriers in SD group was significantly higher than that in control group (P<0.01); while those of ε2 and ε3 genotypes were lower in SD group as compared with control group. CONCLUSIONS: We concluded that in the elderly Han Chinese residents of Chongqing aged 60 years and over, ApoE-ε3/3 and ApoE-ε2/2 were the most and least prevalent genotypes, respectively. Further, based on strong linkage, ApoEε4 allele might be a significant risk factor for the development of senile dementia.

[Magnetic resonance imaging characteristics of unilateral versus bilateral intraplaque hemorrhage in patients with carotid atherosclerotic plaques].

OBJECTIVE: To investigate the difference in the vulnerability of carotid atherosclerotic plaques in patients with unilateral and bilateral intraplaque hemorrhage (IPH). METHODS: A retrospective analysis was conducted among 44 patients with unilateral IPH (30 cases) or bilateral IPH (14 cases) in the carotid plaques detected by magnetic resonance imaging (MRI) in our hospital between December, 2009 and December, 2012. The age, maximum wall thickness and incidence of fibrous cap rupture were compared between the two groups. RESULTS: Compared with those with unilateral IPH, the patients with bilateral IPHs had a significantly younger age (66.6∓9.4 years vs 73.7∓9.0 years, P=0.027), a significantly greater maximum plaque thickness (6.3∓1.9 mm vs 5.0∓1.3 mm, P=0.035) and a higher incidence of ulcers (50% vs 13.3%, P=0.025). Logistic regression analysis revealed a significant association between bilateral IPHs and the occurrence of ulcer with an odd ratio (OR) of 6.5 (95% confidence interval [CI]: 1.5-28.7, P=0.014). After adjustment for gender in Model 1, bilateral IPHs were still significantly associated with presence of ulcer (OR=5.7, 95%CI: 1.1-29.2, P=0.036). But after adjustment for age (P=0.131) or maximum plaque thickness (P=0.139) in model 2, no significant correlation was found between bilateral IPHs and the presence of ulcer. CONCLUSION: Compared with patients with unilateral IPH, those with bilateral IPHs are at a younger age and have a greater plaque burden and a higher incidence of fibrous cap rupture, suggesting a greater vulnerability of the carotid plaques in patients with bilateral IPHs.

Clinical investigation of fasudil for the prevention of cerebral vasospasm in extracranial carotid artery stenting.

To evaluate fasudil hydrochloride for the prevention of cerebral vasospasm (CVS) in extra-cranial carotid angioplasty and stenting (CAS). We retrospectively analyzed 178 patients with unilateral CAS who were given intravenous fasudil hydrochloride during the perioperative period. CVS, hypotension, stroke, and mortality incidence rates were recorded. Of the cohort studied, 80.9 % patients exhibited no local CVS, asymptomatic vasospasm was observed in 17.4 % patients and symptomatic vasospasm in 1.7 % patients via DSA imaging. All CVS was relieved and symptoms disappeared after intra-arterial infusion of papaverine hydrochloride. Intracerebral hemorrhage occurred in two cases during the perioperative period, one of which resulted in death. CVS is a severe complication of CAS. Fasudil hydrochloride can rapidly relieve cerebral vasospasm, has no selective effect on cerebral vasculature, and little influence on blood pressure. It is suitable for the prevention of CVS during interventional treatment of ischemic cerebrovascular disease.

Prevention of hemodynamic instability in extra-cranial carotid angioplasty and stenting using temporary transvenous cardiac pacemaker.

Hemodynamic instability is a common condition during extra-cranial carotid angioplasty and stenting (CAS). We evaluated the safety and efficacy of prophylactic placement of temporary cardiac pacemaker during extra-cranial CAS for the prevention of hemodynamic instability. For this, forty-seven carotid artery stents were deployed in 41 high-risk patients. Temporary transvenous cardiac pacemakers were inserted before CAS procedure. The pacers were set to capture a heart rate <60 bpm. Clinical symptoms, blood pressure, heart rate, and pacing activation were monitored and data were collected. We found that pacing occurred in 25 carotid lesions during balloon predilatation; pacemakers were activated transiently in 25 patients. The longest pacing continued for 1 day. Among cases with pacemaker activation, 1 patient developed post-procedural symptomatic hypotension that lasted for 4 days. No related complications were observed. It was, therefore, concluded that pacing was technically effective in producing electrical ventricular responses and was hemodynamically effective in 25 carotid lesions which underwent balloon predilatation. The prophylactic use of a temporary transvenous cardiac pacemaker during CAS was rapid and effective in controlling peri-operative hemodynamic instability and preventing stroke and other complications. The prophylactic use of temporary pacemaker is particularly recommended for patients at high risk for developing hemodynamic instability.

PPARγ attenuates intimal hyperplasia by inhibiting TLR4-mediated inflammation in vascular smooth muscle cells.

AIMS: Peroxisome proliferator-activated receptor γ (PPARγ) has been reported to attenuate intimal hyperplasia. This study aimed to test the hypothesis that PPARγ inhibits intimal hyperplasia through suppressing Toll-like receptor 4 (TLR4)-mediated inflammation in vascular smooth muscle cells. METHODS AND RESULTS: TLR4(-/-) mice on a C57BL/6J background were used. Increased TLR4 and pro-inflammatory cytokines were observed in wire-injury-induced carotid neointima and in platelet-derived growth factor (PDGF)-activated vascular smooth muscle cells. The TLR4 deficiency protected the injured carotid from neointimal formation and impaired the cellular proliferation and migration in response to lipopolysaccharide and PDGF. Rosiglitazone attenuated intimal hyperplasia. Overexpression of PPARγ suppressed PDGF-induced proliferation and migration and inhibited TLR4-mediated inflammation in vascular smooth muscle cells, while PPARγ silencing exerted the opposite effect. Lipopolysaccharide counteracted the inhibitory effect of PPARγ on PDGF-induced proliferation and migration. Eritoran suppressed the proliferation and migration induced by PDGF and PPARγ silencing. Vascular smooth muscle cells derived from TLR4(-/-) mice showed impaired proliferation and migration upon PDGF activation and displayed no response to PPARγ manipulation. CONCLUSION: PPARγ inhibits vascular smooth muscle cell proliferation and migration by suppressing TLR4-mediated inflammation and ultimately attenuates intimal hyperplasia after carotid injury.

Vasospasm after subarachnoid hemorrhage: a 3D rotational angiography study.

BACKGROUND AND PURPOSE: the purpose of this study was to investigate the clinical value of 3D rotational angiography (3DRA) for evaluation of cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage (SAH) by comparison with 2D digital subtraction angiography (DSA). METHODS: forty-six patients who had undergone 2D DSA and 3DRA for evaluation of cerebral vasospasm following SAH were retrospectively analyzed. 3DRA was routinely performed after standard 2D DSA. 3D volume rendering images were created from 3DRA dataset and compared with DSA for the detection and characterization of vasospasm. RESULTS: Of the 46 patients investigated, 25 had vasospasm on 2D DSA images. No vasospasm was observed in 21 patients with aneurysmal SAH. According to the reference standard of DSA, 46 spastic segments were found in 25 patients with vasospasms. A total of 51 spastic segments were found on 3DRA volume rendering angiograms. The sensitivity, specificity, positive and negative predictive values of 3DRA for detecting vasospasm were 100, 76, 90, 100%, respectively. CONCLUSION: the pseudo-spasm phenomenon was frequently observed on 3DRA volume rendering images. 3DRA was less useful than 2D DSA for evaluation of vasospasm after SAH.