Cerebrospinal fluid viral escape in HIV patients on antiretroviral therapy: A systematic review of reported cases.

Cerebrospinal fluid (CSF) viral escape rarely occurs when HIV is detected in the CSF, while it is undetectable in the blood plasma or detectable in CSF at levels that exceed those in the blood plasma. We conducted this review to comprehensively synthesise its clinical presentation, diagnosis, management strategies and treatment outcomes. A review registered with PROSPERO (CRD42023475311) searched evidence across PubMed/MEDLINE, Embase, Web of Science, Scopus, and Google Scholar to gather articles (case reports/series) that report on CSF viral escape in people living with HIV (PLHIV) on antiretroviral therapy (ART). The quality of studies was assessed based on the domains of selection, ascertainment, causality, and reporting. A systematic search identified 493 articles and 27 studies that include 21 case reports, and six case series were involved in the review. The studies reported 62 cases of CSF viral escape in PLHIV. The majority were men (66.67%), with a median age of 43 (range: 28-73) years. Approximately, 31 distinct symptoms were documented, mostly being cognitive dysfunction, gait abnormalities, and tremors (12.51%). Diagnosis involved blood and CSF analysis, magnetic resonance imaging, and neuropsychological assessments. Over 36 ART regimens were employed, with a focus on ART intensification; almost one-third of the regimens contained Raltegravir (integrase strand transfer inhibitor). The outcomes showed 64.49% full recovery, 30.16% partial recovery, and 4.76% died. When neuropsychological symptoms manifest in PLHIV, monitoring for CSF viral escape is essential, regardless of plasma viral suppression. Personalised treatment strategies, particularly ART intensification, are strongly advised for optimising treatment outcomes in PLHIV diagnosed with CSF HIV escape.

Arterial pulsation dependence of perivascular cerebrospinal fluid flow measured by dynamic diffusion tensor imaging in the human brain.

Perivascular cerebrospinal fluid (pCSF) flow is a key component of the glymphatic system. Arterial pulsation has been proposed as the main driving force of pCSF influx along the superficial and penetrating arteries; however, evidence of this mechanism in humans is limited. We proposed an experimental framework of dynamic diffusion tensor imaging with low b-values and ultra-long echo time (dynDTIlow-b) to capture pCSF flow properties during the cardiac cycle in human brains. Healthy adult volunteers (aged 17-28 years; seven men, one woman) underwent dynDTIlow-b using a 3T scanner (MAGNETOM Prisma, Siemens Healthcare, Erlangen, Germany) with simultaneously recorded cardiac output. The results showed that diffusion tensors reconstructed from pCSF were mainly oriented in the direction of the neighboring arterial flow. When switching from vasoconstriction to vasodilation, the axial and radial diffusivities of the pCSF increased by 5.7 % and 4.94 %, respectively, suggesting that arterial pulsation alters the pCSF flow both parallel and perpendicular to the arterial wall. DynDTIlow-b signal intensity at b=0 s/mm2 (i.e., T2-weighted, [S(b=0 s/mm2)]) decreased in systole, but this change was ∼7.5 % of a cardiac cycle slower than the changes in apparent diffusivity, suggesting that changes in S(b=0 s/mm2) and apparent diffusivity arise from distinct physiological processes and potential biomarkers associated with perivascular space volume and pCSF flow, respectively. Additionally, the mean diffusivities of white matter showed cardiac-cycle dependencies similar to pCSF, although a delay relative to the peak time of apparent diffusivity in pCSF was present, suggesting that dynDTIlow-b could potentially reveal the dynamics of magnetic resonance imaging-invisible pCSF surrounding small arteries and arterioles in white matter; this delay may result from pulse wave propagation along penetrating arteries. In conclusion, the vasodilation-induced increases in axial and radial diffusivities of pCSF and mean diffusivities of white matter are consistent with the notion that arterial pulsation can accelerate pCSF flow in human brain. Furthermore, the proposed dynDTIlow-b technique can capture various pCSF dynamics in artery pulsation.

Does hyperphenylalaninemia induce brain glucose hypometabolism? Cerebral spinal fluid findings in treated adult phenylketonuric patients.

Despite numerous studies in human patients and animal models for phenylketonuria (PKU; OMIM#261600), the pathophysiology of PKU and the underlying causes of brain dysfunction and cognitive problems in PKU patients are not well understood. In this study, lumbar cerebral spinal fluid (CSF) was obtained immediately after blood sampling from early-treated adult PKU patients who had fasted overnight. Metabolite and amino acid concentrations in the CSF of PKU patients were compared with those of non-PKU controls. The CSF concentrations and CSF/plasma ratios for glucose and lactate were found to be below normal, similar to what has been reported for glucose transporter1 (GLUT1) deficiency patients who exhibit many of the same clinical symptoms as untreated PKU patients. CSF glucose and lactate levels were negatively correlated with CSF phenylalanine (Phe), while CSF glutamine and glutamate levels were positively correlated with CSF Phe levels. Plasma glucose levels were negatively correlated with plasma Phe concentrations in PKU subjects, which partly explains the reduced CSF glucose concentrations. Although brain glucose concentrations are unlikely to be low enough to impair brain glucose utilization, it is possible that the metabolism of Phe in the brain to produce phenyllactate, which can be transported across the blood-brain barrier to the blood, may consume glucose and/or lactate to generate the carbon backbone for glutamate. This glutamate is then converted to glutamine and carries the Phe-derived ammonia from the brain to the blood. While this mechanism remains to be tested, it may explain the correlations of CSF glutamine, glucose, and lactate concentrations with CSF Phe.

Impact of introducing a new biological matrix into a validated bioanalytical method: Focus on matrix protein content.

International guidance on bioanalytical method validation recommends the practice of partial validation when introducing a new matrix from the same species into a previously fully validated assay. Planning the partial validation protocol should include an evaluation of analyte chemistry, consideration of sample container materials, and a comparison of properties between the relevant biological matrices. Transition of a serum/plasma-validated bioanalytical method to analysis from a low-protein matrix, such as urine, cerebral spinal fluid, or oral fluid can result in inconsistent analyte recovery. The low recovery can potentially be mistaken for signal suppression or lack of drug stability and may be more pronounced in low-concentration or low-volume samples. In addition, adsorption and absorption interactions with containers may be exacerbated in low-protein matrices. Several possibilities exist for mitigating the impact of non-specific binding and low-protein matrices, including surfactants, bovine serum albumin, and ß-cyclodextrin. Finally, higher matrix protein can facilitate analyte stability. Given all this, matrix protein content should not be overlooked when anticipating a partial bioanalytical method validation.

Post-translational modifications linked to preclinical Alzheimer's disease-related pathological and cognitive changes.

INTRODUCTION: In this study, we leverage proteomic techniques to identify communities of proteins underlying Alzheimer's disease (AD) risk among clinically unimpaired (CU) older adults. METHODS: We constructed a protein co-expression network using 3869 cerebrospinal fluid (CSF) proteins quantified by SomaLogic, Inc., in a cohort of participants along the AD clinical spectrum. We then replicated this network in an independent cohort of CU older adults and related these modules to clinically-relevant outcomes. RESULTS: We discovered modules enriched for phosphorylation and ubiquitination that were associated with abnormal amyloid status, as well as p-tau181 (M4: ß = 2.44, p < 0.001, M7: ß = 2.57, p < 0.001) and executive function performance (M4: ß = -2.00, p = 0.005, M7: ß = -2.39, p < 0.001). DISCUSSION: In leveraging CSF proteomic data from individuals spanning the clinical spectrum of AD, we highlight the importance of post-translational modifications for early cognitive and pathological changes.

Comparative evaluation of the diagnostic and prognostic performance of CNSide™ versus standard cytology for leptomeningeal disease.

Background: This retrospective study compares the real-world performance of cerebrospinal fluid (CSF) CNSide™ versus cytology in leptomeningeal disease (LMD). Methods: Consecutive patients with suspected LMD who underwent lumbar punctures for CSF cytology and CNSide™ from January 2020 to December 2022 were reviewed. LMD was classified by EANO criteria. Descriptive statistics, confusion matrix, Kaplan-Meier curves, and Cox proportional regression were used. Results: Median age for 87 evaluable patients was 63 years (range: 23-93); 82 (94%) met EANO criteria for possible/probable/confirmed LMD (EANO/LMD). The commonest primary cancers were breast (36,44.0%) and lung (34,41.5%). Primary lung harbored actionable mutations in 18 (53.0%); primary breast expressed hormone receptors in 27 (75%), and HER2 amplification in 8 (22%). Uncontrolled systemic disease was detected in 35 (40%), while 25 (46%) received systemic therapy with medium/high CNS penetrance at LMD diagnosis. The median time from initial cancer to LMD diagnosis was 31 months (range: 13-73). LMD was confirmed by CSF cytology in 23/82 (28%), all identified by CNSide™. CNSide™ identified 13 additional cases (36/82, 43.9%), increasing diagnostic yield by 56.5%. Median overall survival (mOS) was 31 weeks (95%CI: 21-43), significantly worse for CNSide™ positive versus negative: 4.0 versus 16.0 weeks, respectively (HR = 0.50, P = .010). While survival since LMD diagnosis did not differ by histology, time to LMD diagnosis from initial cancer diagnosis was longer for breast (48.5 months, IQR: 30.0-87.5) versus lung (8 months, IQR:0.5-16.0) cohorts. mOS was longer for patients eligible for intrathecal chemotherapy (HR: 0.189, 95%CI: 0.053-0.672, P = .010). Conclusions: This retrospective, real-world analysis of CNSide™ showed increased sensitivity versus cytology and provided clinically relevant molecular CSF analyses.

1-Octanol-assisted ultra-small volume droplet microfluidics with nanoelectrospray ionization mass spectrometry.

BACKGROUND: Droplet microfluidics with push-pull and microdialysis sampling from brain slices, cultured cells and engineered tissues produce low volume mass limited samples containing analytes sampled from the extracellular space. This sampling approach coupled to mass spectrometry (MS) detection allows evaluation of time-dependent chemical changes. Our goal is an approach for continuous sampling and segregation of extracellular samples into picoliter droplets followed by the characterization of the droplets using nanoelectrospray ionization (nESI) MS. The main focus here is the optimization of the carrier oil for the microfluidic device that neither affects the stability of picoliter droplets nor compatibility with MS detection of a range of analytes. RESULTS: We developed and characterized a 1-octanol-assisted ultra-small volume droplet microfluidic nESI MS system for the analysis of neurotransmitters in distinct samples including cerebrospinal fluid (CSF). The use of a 1-octanol oil phase was effective for generation of aqueous droplets as small as 65 pL and enabled detection of acetylcholine (ACh) and gamma-aminobutyric acid (GABA) in water and artificial CSF. Continuous MS analysis of droplets for extended periods up to 220 min validated the long-term stability of droplet generation and analyte detection by nESI-MS. As an example, ACh response demonstrated a linear working range (R2 = 0.99) between 0.4 µM and 25 µM with a limit of detection of 370 nM (24 amol), enabling its quantitation in rodent CSF. SIGNIFICANCE: The established droplet microfluidics - nESI MS approach allows the analysis of microenvironments at high spatiotemporal resolution. The approach may allow microsampling and monitoring of spatiotemporal dynamics of neurochemicals and drugs in the brain and spinal cord of live animals.

Is cranioplasty the optimal treatment for contralateral subdural effusion after decompressive craniectomy?: a case report.

Introduction and importance: Contralateral subdural effusion (CSDE) is a rare complication secondary to decompressive craniectomy (DC), which can lead to encephalocele and neurologic deterioration. The authors report a case that confirm the existence of unidirectional membrane valve, and cranioplasty is an effective treatment for CSDE. Case presentation: The authors reported a case of 43-year-old female was diagnosed with ruptured intracranial aneurysm and treated with interventional embolization. She underwent DC because of postoperative cerebral infarction subsequently. Her conscious state deteriorated accompanied by encephalocele in postoperative 2 week. A craniocerebral computed tomography (CT) confirmed the diagnosis of CSDE with cerebral hernia. A compression bandaging of the skull defect was applicated, whereas, her conscious state progressive deteriorated. She was transferred to the author's hospital where she underwent burr-hole drainage and clinical symptom has been improved. However, a relapse of CSDE was observed after the removal of drainage tube. Continuous lumbar drainage was employed, and which was ineffective for CSDE in this case. Finally, she underwent cranioplasty, with the help of drainage of subdural effusion, CSDE was completely resolved. Clinical discussion: CSDE is occasionally observed in patients after DC. Intracranial pressure (ICP) gradient and unidirectional membrane valve are the possible mechanisms of CSDE. At present, there is no optimal therapy for CSDE. For symptomatic CSDE patients, one or more treatment measures should be applicated. Conclusion: Cranioplasty is one of the curative and optimal method to treat symptomatic CSDE patients, early cranioplasty combined with burr-hole drainage should be performed for conservative treatment failed and intractable cases.

Sex modifies effects of imaging and CSF biomarkers on cognitive and functional outcomes: a study of Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory and functional impairments. Two of 3 patients with AD are biologically female; therefore, the biological underpinnings of this diagnosis disparity may inform interventions slowing the AD progression. To bridge this gap, we conducted analyses of 1078 male and female participants from the Alzheimer's Disease Neuroimaging Initiative to examine associations between levels of cerebral spinal fluid (CSF)/neuroimaging biomarkers and cognitive/functional outcomes. The Chow test was used to quantify sex differences by determining if biological sex affects relationships between the studied biomarkers and outcomes. Multiple magnetic resonance imaging (whole brain, entorhinal cortex, middle temporal gyrus, fusiform gyrus, hippocampus), position emission tomography (AV45), and CSF (P-TAU, TAU) biomarkers were differentially associated with cognitive and functional outcomes. Post-hoc bootstrapped and association analyses confirmed these differential effects and emphasized the necessity of using separate, sex-stratified models. The studied imaging/CSF biomarkers may account for some of the sex-based variation in AD pathophysiology. The identified sex-varying relationships between CSF/imaging biomarkers and cognitive/functional outcomes warrant future biological investigation in independent cohorts.

Adeno-associated virus vector delivery to the brain: Technology advancements and clinical applications.

Adeno-associated virus (AAV) vectors have emerged as a promising tool in the development of gene therapies for various neurological diseases, including Alzheimer's disease and Parkinson's disease. However, the blood-brain barrier (BBB) poses a significant challenge to successfully delivering AAV vectors to the brain. Strategies that can overcome the BBB to improve the AAV delivery efficiency to the brain are essential to successful brain-targeted gene therapy. This review provides an overview of existing strategies employed for AAV delivery to the brain, including direct intraparenchymal injection, intra-cerebral spinal fluid injection, intranasal delivery, and intravenous injection of BBB-permeable AAVs. Focused ultrasound has emerged as a promising technology for the noninvasive and spatially targeted delivery of AAV administered by intravenous injection. This review also summarizes each strategy's current preclinical and clinical applications in treating neurological diseases. Moreover, this review includes a detailed discussion of the recent advances in the emerging focused ultrasound-mediated AAV delivery. Understanding the state-of-the-art of these gene delivery approaches is critical for future technology development to fulfill the great promise of AAV in neurological disease treatment.

A rare case of Sphingomonas paucimobilis ventriculitis.

Introduction: Nosocomial ventriculitis is a severe infection that habitually plagues neurological intensive care units. It is usually associated with external ventricular drains. Unfortunately, classic cerebral spinal fluid parameters are less specific and sensitive compared to community acquired meningitis. This is in part secondary to indolent bacteria commonly infecting external ventricular drains leading to ventriculitis. Case report: Herein, a rare case of Sphingomonas paucimobilis ventriculitis in an immunocompetent host is reported. The patient had classic symptoms of ventriculitis, but her cerebral spinal fluid parameters were benign and initial cultures were negative. Consequently, treatment was tailored to an assumed respiratory infection only to have recurrence of her symptoms. Repeat analysis of her cerebral spinal fluid was again benign, but her cerebral spinal fluid culture grew S. paucimobilis. Subsequently, the patient was treated with cefepime, which resolved her symptoms. She completed a two-week course and has had no recurrence of her infection. Conclusions: This case reinforces the need for clinicians to have heightened awareness of this emerging pathogen, its antibiotic resistance patterns, and the unique composition of this bacterium's cell wall which has ramifications on disease presentation.

Utility of Cerebrospinal Fluid Protein Levels as a Potential Predictive Biomarker of Disease Severity in HIV-Associated Cryptococcal Meningitis.

Background: Cerebrospinal fluid (CSF) protein levels exhibit high variability in HIV-associated cryptococcal meningitis from being normal to markedly elevated. However, the clinical implications of CSF protein levels in cryptococcal meningitis remain unclear. Methods: We analysed data from 890 adults with HIV-associated cryptococcal meningitis randomized into two clinical trials in Uganda between 2015 and 2021. CSF protein was grouped into ≥100 mg/dL (n=249) and <100 mg/dL (n=641). We described baseline clinical variables and mortality by CSF protein levels. Results: Approximately one-third of individuals had a baseline CSF protein ≥100 mg/dL. Those with CSF protein ≥100 mg/dL were more likely to present with Glasgow coma scale scores <15 (P<0.01), self-reported seizures at baseline (P=0.02), higher CD4 T-cells (p<0.001), and higher CSF white cells (p<0.001). Moreover, those with a baseline CSF protein ≥100 mg/dL also had a lower baseline CSF fungal burden (p<0.001) and a higher percentage of sterile CSF cultures at day 14 (p=0.02). Individuals with CSF protein ≥100 mg/dL demonstrated a more pronounced immune response consisting of upregulation of immune effector molecules pro-inflammatory cytokines, type-1 T-helper cell cytokines, type-3 chemokines, and immune-exhaustion marker (p<0.05). 18-week mortality risk in individuals with a CSF protein <100 mg/dL was 34% higher, (unadjusted Hazard Ratio 1.34; 95% CI, 1.05 to 1.70; p=0.02) than those with ≥100 mg/dL. Conclusion: In cryptococcal meningitis, individuals with CSF protein ≥100 mg/dL more frequently presented with seizures, altered mental status, immune activation, and favourable fungal outcomes. Baseline CSF protein levels may serve as a surrogate marker of immune activation and prognosis.

A rare case of tumefactive demyelination of brain: A case report and literature review.

This case report highlights the diagnostic challenges encountered in a 30-year-old female presenting with fever followed by Wernicke's aphasia without right-sided weakness, ultimately diagnosed as tumefactive demyelination (TD). TD is a rare neurological condition often misidentified as brain tumors or inflammatory disorders. The case emphasizes the importance of precise differentiation through advanced magnetic resonance imaging, showing restricted diffusion at lesion edges and the absence of gadolinium enhancement. Accurate diagnosis is crucial for tailored treatment and prognostic assessment. This case contributes to our understanding of TD and underscores the need for continued research and collaboration in the field of rare neurological disorders.

Suspected transcutaneous cerebral spinal fluid leakage without postural headache after implantable intrathecal drug delivery system removal: A case report

A 55-year-old man with an implantable intrathecal drug delivery system (IDDS) implant removal surgery was performed to control a suspected implant infection. Clear discharge from a lumbar wound was detected after IDDS removal, but transcutaneous cerebral spinal fluid (CSF) leakage was not suspected because the patient did not suffer from a postural headache. Finally, a suspected CSF leakage was resolved with a single epidural blood patch.

The study on diagnostic feasibility of CSF Aβ42, T-tau, P-tau181 detection in Alzheimer dementia / 中国神经精神疾病杂志

Objective To explore the diagnostic feasibility of Alzheimer disease (AD) associated CSF biomarker (CSF Aβ42, T-tau, and P-tau181) through establishing the cutoff value and the sensitivity and specificity of each biomarker. Methods Seventeen AD dementia patients were enrolled from Peking university first hospital during 2015 July and 2017 Feb including 5 patients that received PET scan using Pittsburgh compound-B. Forty-nine cognitive normal subjects were also enrolled as controls according to the protocol. The levels of Aβ42, T-tau, P-tau181 and the ratio of Aβ42/T-tau、Aβ42/ P-tau181 from all participants were assessed using the innotest-ELISA methods and cutoff value,sensitivity as well as specificity of each biomarker were determined according to the ROC curve. Results There were significant differences in all biomarkers between the cognitive normal controls group and AD dementia group. The cutoff value of Aβ42, T-tau, P-tau181, Aβ42/T-tau and Aβ42/ P-tau181 were 511 ng/mL, 322 ng/mL, 63 ng/mL, 14.72 and 1.74. The sensitivity were 64.7% in Aβ42, 88.2% in T-tau, 58.8% in P-tau181, 82.35% in Aβ42/T-tau and 76.47% in Aβ42/ P-tau181, respectively. The specificity were 97.05% in Aβ42, 75.5% in T-tau, 93.87% in P-tau181, 95.51 % in Aβ42/T-tau and 93.87% in Aβ42/P-tau181, respectively. Conclusion Alzheimer disease associated biomarkers (CSF Aβ42,T-tau, and P-tau181) can distinguish the cognitive normal subjects from AD dementia patients. The methods are reliable and the sensitivity as well as specificity of each biomarker are good which are close to the values reported in the literatures. Thus, this methodology is worth being promoted in the clinic.

Análise do líquido cérebro-espinhal de três doenças do sistema nervoso central de cães / Analysis of cerebral-spinal fluid of three central nervous system diseases of dogs

Foi realizado um estudo retrospectivo do líquido cérebro-espinhal de cães (LCE), atendidos pelo Serviço de Neurologia do Hospital Veterinário da Instituição, de 2004 a 2015, com o objetivo de analisar os resultados de cães com sinais neurológicos, comparar as alterações encontradas em dois locais de colheita no mesmo paciente e verificar se esse exame auxiliou o clínico em reforçar a suspeita clínica das principais doenças do sistema nervoso central. A pleocitose linfocítica esteve presente em 78,3% (29/37) das amostras de cães com cinomose e em 23,2% (10/43) de cães com DDIV. Houve dissociação albuminocitológica (DAC) em 73% (19/26) das amostras de cães com tumores IC e em 64,3% (9/14) de cães com tumores envolvendo a ME. Em cães com DDIV, houve significância estatística (p<0,05) entre o grau de disfunção neurológica e o total de células nucleadas (TCN) e total de proteínas (TP). Em 29 cães, houve a colheita do LCE da cisterna magna e da cisterna lombar e em 12 (41,4%) os resultados foram diferentes entre as duas amostras colhidas do mesmo cão, onde dois (6,9%) apresentaram alteração na amostra colhida cranial à lesão. Pode-se concluir que a pleocitose linfocítica foi a principal alteração encontrada no LCE de cães com cinomose e DDIV e DAC nas neoplasias, IC e ME, cães acometidos pela DDIV apresentaram sinais neurológicos mais severos conforme o TCN e o TP aumentaram e o LCE sofreu alteração, mesmo colhido cranial ao local da lesão e auxiliou o clínico em reforçar a suspeita clínica, mas não confirmou, as principais doenças neurológicas em cães.(AU)

A retrospective study including the analysis of the cerebrospinal fluid (CSF) of dogs neurologically affected was conducted by the Neurology Service of the Veterinary Hospital at the Institution, between 2004 and 2015. The aim of this study was to analyze the results of the CSF of dogs with neurological signs, and compare the changes in the CSF in two sampling sites in the same patient and see if this test helped the clinician to strengthen clinical suspicion of the major diseases of the central nervous system. Lymphocytic pleocytosis was present in 78.3% (29/37) of samples from dogs with distemper and in 23.2% (10/43) of samples from dogs with IVDD. The albumin cytologic dissociation (ACD) was found in 73% (19/26) of samples from dogs with IC tumors and in 64.3% (9/14) from dogs with tumors involving the SC. For dogs with IVDD, there was statistical significance (p<0.05) between the degree of neurological dysfunction and the total nucleated cells (TNC) and total protein (TP). In 29 dogs, CSF was collected from the cistern magna and the lumbar and in 12 (41.4%) the results were different between the samples of the same dog, where two cases (6,9%) showed alterations in the sample collected cranial to the injury. It can be concluded that the lymphocytic pleocytosis was the main alteration found in the CSF of dogs with distemper and IVDD and ACD in tumors. Dogs affected by IVDD had more severe neurological signs as TNC and TP increased and the CSF was altered even collected cranial to the lesion site and helped the clinician to strengthen the clinical suspicion, but not confirm, the major neurological diseases in dogs.(AU)

Evidence-based clinical practice guidelines for the treatment of dural tears and the consequent cerebrospinal fluid leak during spine surgery / 中华外科杂志

Dural tears (DT) and the consequent cerebral spinal fluid (CSF) leak are not rare in spine surgeries. CSF leak can be troublesome, leading to pseudomeningocele, cutaneous CSF fistula, and meningitis. Revision surgery is unavoidable in some cases. The reported incidences of DT and CSF leak are different according to the various pathologies. Ossification of the posterior longitudinal ligament, revision spine surgery and multi-segment laminectomy have higher risks for DT. Various techniques have been described to manage this complication, such as bed rest, repair with dural substitutes, fibrin glue, gelatin sponge, lumbar drain, muscle flap, etc.Through objective evaluation of the evidence and transparency in the process of making recommendations, it is Chinese Association of Orthopaedic Surgeons′ goal to develop evidence-based clinical practice guidelines for the treatment of incidental DT and the consequent CSF leak during spine surgery. The current clinical guidelines focus on 9 clinical questions and the strength of recommendations were made based on the quality of the literature. The work group considers that this guideline recommendations aim to assist in delivering optimum, efficacious treatment and functional recovery from this complication.

Effect of lead exposure on function of blood-cerebrospinal fluid barrier and ZO-1 and occludin protein expression in vitro / 中国药理学与毒理学杂志

OBJECTIVE To establish an in vitro blood-cerebrospinal fluid barrier (BCB) model to investigate the underlying mechanism of lead-induced BCB injuries.METHODS The in vitro BCB model was established by Z310 cells.Different concentrations of Pb(AC)2 (2.5,5.0 and 10.0 mmol·L-1) were used for 24,48 and 72 h.Transendothelial electrical resistance (TEER) and flux of FITC-dextran were performed to determine the permeability of the in vitro BCB model.Western blotting and immunofluorescence methods were used to observe the expression of tight junction protein ZO-1 and occludin.RESULTS Compared with control group,Pb(AC)2 2.5,5.0 and 10.0 mmol· L-1 exposure for 48 h to Z310 cells had no significant effect on survival rate and density.TEER in different groups was gradually increasing.At the 12th day after Pb(AC)2 exposure,the values of TEER and flux of FITC-dextran in Pb(AC)2 5 and 10 mmol· L-1 groups were significantly decreased (P＜0.05).Western blotting and immunofluorescence images showed that the expression of ZO-1 and occludin were significantly decreased (P＜0.05) after Pb(AC)2 exposure for 48 h.CONCLUSION Lead exposure can cause the breakdown of BCB barriers,and this effect may be mediated by reducing the expression of ZO-1 and occludin proteins.

Effects of hypoxia on production of ATP and expression of mitochrome C in human meningothelial cells as the cerebral fluid-optic nerve barrier / 中华实验眼科杂志

Background BackgroundMeningothelial cells (MECs) are major cell type in the meningeal sheath around optic nerve,which form a fluid barrier between optic nerve and the cerebral spinal fluid.The impairment of the cerebral fluid-optic nerve barrier probably affects the balance of cerebral fluid components.Currently,the investigation on the role of MECs in neuropathy is less performed.Objective This study attempted to explore hypoxia-induced function changes of MECs,and to shed a new clus for the future research of optic nerve disorders.Methods Human MECs strains were cultured in vitro and cell suspension was prepared with the cell densities of 2.5 ×103/hole,5.0× 103/hole and 1 x 104 /hole,respectively.The suspensions of 100 μl were separately collected to incubate in 96-well plates and cultivated for 2 days in 21％ O2(normoxia group) or 1％ O2(hypoxia group).MTS was used to detect and compare the proliferative value (A490) of MECs between the normoxia group and the hypoxia group.The changes of MECs diameter and volume were measured by CASY1 assay.ATP product in the cells after MECs exposed to different oxygen environments with or without substrate (100 mmol/L pyruvate and 100 mmol/L malate) for 1,2 days were assayed by Luminometer method.The expression and distribution of cytochrome C in the cells of the normoxia group and the hypoxia group were determined by immunofluorescence.Results A490 of MECs in the 2.5× 103/hole,5.0× 103/hole and 1 × 104/hole were 0.399±0.009,0.393±0.009 and 0.496±0.026 in the hypoxia group,which were lower than 0.424±0.131,0.413±0.111 and 0.537±0.021 in the normoxia group (t =3.777,P =0.004 ; t =3.251,P =0.009 ; t =3.037,P =0.013).Compared with the normoxia group,the diameter and volume were significantly increased in the hypoxia group ([20.970 ±0.127] μm vs.[21.198 ±0.048] μm,t =-3.762,P=0.006; [5805±73] fl vs.[6026±106] fl,t=-4.124,P=0.002).ATP products were (0.900±0.225)mmol/(L· g) and (0.952± 0.075) mmol/(L · g) in the hypoxia group and the hypoxia+substrate group,which were significantly lower than (1.389±0.145) mmol/(L · g) and (1.401±0.122) mmol/(L · g) in the normoxia group and the normoxia +substrate group (P =0.001,0.002,0.001).Immunofluorescense staining showed that the green fluorescence of cytochrome C located at mitochondria of MECs in the normoxia group,but in the hypoxia group,cytochrome C distributed in the cytoplasm extensively.Conclusions Hypoxia induces malfunction of MECs,which might impact the intact of the cerebral spinal fluid-optic nerve barrier and therefore influence the microenvironment of the subarachnoid space and neuronal function.

Changes of argiuine vaso-pression in blood and cerebral spinal fluid(CSF)in patients with severe brain injury after treated with mild hypothermia / 中华急诊医学杂志

Objective To study the changes of blood arginine vaso-pression(AVP)levels in patients with severe brain injury after treated with mild hypotherima.Methods Seventy-eight patients with severe brain injury were divided into mild hypothermia(33～35℃)group and normothermia group.The blood AVP levels and CSF AVP levels were determined at the third and the seventh day after brain injury.Results The AVP levels in blood and CSF of mild hypothermia group were lower than those of the normothermia group at the third and seventh day after brain injury(P＜0.05).According to GOS,prognosis of the mild hypothermia group was better than that of the nonnotbcrmia group(P＜0.05).Conclusion The mild hypothermia treatment may have inhibitive effects on the production of blood AVP,CSF AVP,and brain edema.Mild hypothermia is an effective method in the treatment of acute severe brain iniury in reducing the mortality and in increasing the survival rate.