Sistema glinfático: aspectos anatómicos, fisiológicos e implicaciones clínicas / Glymphatic system: Anatomo-physiological principles and their clinical implications

Introducción: El sistema glinfático comprende el conjunto de rutas perivasculares tanto arteriales como venosas que se encuentran en estrecha asociación con células astrogliales y que permiten la interacción entre el líquido cefalorraquídeo (LCR) y el líquido intersticial cerebral (LIC), para llevar a cabo procesos como la depuración de los metabolitos de desecho celular, o la distribución de nutrientes, así como contribuir al metabolismo cerebral local, la transmisión de volumen y la señalización paracrina cerebral. Contenidos: Este artículo busca profundizar en los conceptos anatómicos y fisiológicos, hasta el momento descritos, sobre este sistema macroscópico de transporte. Se realiza una búsqueda bibliográfica de revisiones y estudios experimentales sobre la anatomía, la fisiología y las implicaciones fisiopatológicas del sistema glinfático. Conclusiones: La identificación anatómica y funcional del sistema glinfático ha ampliado el conocimiento sobre la regulación del metabolismo cerebral en cuanto a distribución de nutrientes y cascadas de señalización celular. Al establecer una interacción entre el espacio subaracnoideo subyacente y el espacio intersticial cerebral, el sistema glinfático surge como uno de los mecanismos protagonistas de la homeostasis cerebral. La disfunción de esta vía hace parte de los mecanismos fisiopatológicos de múltiples trastornos neurológicos, ya sea por la acumulación de macromoléculas, como ocurre en la enfermedad de Alzheimer, o por la reducción del drenaje de sustancias químicas y citocinas proinflamatorias en patologías como la migraña o el trauma craneoencefálico.

Introduction: The glympathic system comprises the set of perivascular routes, arterials or venous, that are found in close relationship with astroglial cells and allow interaction between the cerebrospinal fluid (CSF) and the interstitial brain fluid (ISF), to carry processes like cell-wasting metabolites depuration, nutrients distribution, as well as make a contribution in the local brain metabolism, volumen transmition and brain paracrine signaling. Contents: This article seeks to deepen in the anatomical and physiological concepts, so far described, about this macroscopic transport system. A bibliographic search of reviews and experimental studies on the anatomy, physiology and pathophysiological implications of the glymphatic system is carried out. Conclusions: Anatomical and functional identification of glympathic system has broaden the knowledge about regulation of brain metabolism on the nutrients distribution and cell signaling cascades. When setting an interaction between the subarachnoid space and the brain interstitial space, the glymphatic system arise as one of the leading mechanisms of brain homeostasis. Disfunction of this pathway makes part of the patophysiological mechanisms of multiple neurological disease, either be by collection of macromolecules as in Alzheimer's disease, or by the reduction of inflammatory cytokines and chemical substances drainage as in migraine or traumatic brain injury (TBI).

Multi-slice spiral CT manifestations of perivascular epithelioid cell tumors / 中国基层医药

Objective:To investigate CT manifestations of perivascular epithelioid cell tumors.Methods:The multi-slice spiral CT manifestations in 11 patients with perivascular epithelioid cell tumors which were pathologically confirmed in the First Affiliated Hospital of Shantou University Medical College between October 2012 and August 2021 were retrospectively analyzed.Results:Perivascular epithelioid cell tumors were located in the kidney of eight patients, in the right lobe of the liver of two patients, and in the descending colon of one patient. The largest tumor, approximately 20.0 cm × 26.0 cm × 11.0 cm, was located in the kidney. The smallest tumor, 2.4 cm × 2.6 cm × 3.4 cm, was located in the colon. CT plain scans showed uniform density without bleeding, calcification, or fat in two patients, and non-uniform density with fatty change in two patients. Contrast-enhanced CT images showed non-uniform enhancement in the arterial phase in 10 patients and uniform enhancement in one patient. Contrast-enhanced CT images showed decreased degrees of enhancement of the lesions in 11 patients from the portal venous phase to the delayed phase and dilated and tortuous vascular shadows in 11 patients.Conclusion:The multi-slice spiral CT manifestations of perivascular epithelioid cell tumors are characteristic and the multi-slice spiral CT is of value for the diagnosis of perivascular epithelioid cell tumors.

Research progress in the evaluation of glymphatic system function by the DTI-ALPS method / 中南大学学报(医学版)

The glymphatic system can remove metabolic wastes from the brain, which plays a significant role in maintaining the homeostasis of the central nervous system. It is an important basis for advanced cognitive functions such as learning and memory. Studies have analyzed the function of glymphatic system by diffusion tensor imaging analysis along the perivascular space (DTI-ALPS) recently. Compared with other invasive examinations that require fluorescent tracer technique or the injection of contrast agents, DTI-ALPS can evaluate the hydromechanics of the glymphatic system via quantifying the diffusion rate of water molecules in different directions, which turns out to be a non-invasive in vivo neuroimaging method. The ALPS-index calculated by the DTI-ALPS method is significantly correlated with the cognitive function in diseases of central nervous system and other system and can reflect the dynamic changes of diseases. In general, ALPS-index is expected to become a novel neuroimaging biomarker for predicting prognosis and clinical effects.

Updated Understanding of the Glial-Vascular Unit in Central Nervous System Disorders / 神经科学通报·英文版

The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.

Qualitative and quantitative characteristics of the passive compartment underneath the myocardial bridge comprising the blood vessel adventitia and the perivascular connective tissue / Características cualitativas y cuantitativas del compartimento pasivo debajo del puente miocárdico que comprende la adventicia del vaso sanguíneo y el tejido conectivo perivascular

SUMMARY: Myocardial bridges are inborn anomalies frequently found in authopsies. Although tipically clinically silent, they are occasionally associated with severe clinical manifestations, e.g. myocardial ischemia or even sudden death. The pathophysiology and risk factors for these manifestations have not yet been completely elucidated. The connective tissue underneath the bridge has been considered as one of the factors the symptoms depend on. Thus, the aim of this research was to determine the histological characteristics of the connective tissue lying underneath the myocardial bridge and to contribute to a better understanding of the protective effects this passive compartment might have in prevention of severe clinical manifestations of myocardial bridging. The study was carried out on twenty hearts with myocardial bridges. Length of the bridge was determined using a precise electronic caliper. Sections of the myocardial bridges with the underlying connective tissue were obtained and prepared for qualitative and quantitative analysis. The connective tissue underneath the bridges was composed of adipose tissue and loose connective tissue in different ratios. The tissue underneath thin bridges was predominantly composed of adipose tissue, while loose connective tissue was the dominant component under thick bridges. The myocardial bridges had an average thickness of 0,98 ± 0.44 mm and an average length of 15,25±5,65 mm. We found a strong positive correlation between the myocardial bridge thickness and length (r = 0,860, p = 0,0001). The thickness of the passive connective tissue compartment under the myocardial bridges was 0,58±0,22 mm, and there was no correlation between this parameter and the myocardial bridge thickness (r = -0,011; p = 0,963). In the clinical evaluation of patients with these anomalies it is necessary to take into account independently the myocardial bridge thickness and length on one side and the thickness of the connective tissue lying underneath it on the other.

Los puentes miocárdicos son anomalías congénitas que se encuentran con frecuencia en las autopsias. Aunque típicamente éstos son clínicamente silenciosos, ocasionalmente se asocian con manifestaciones clínicas graves, como isquemia miocárdica o incluso muerte súbita. La fisiopatología y los factores de riesgo de estas manifestaciones aún no se han dilucidado por completo. El tejido conectivo debajo del puente se ha considerado como uno de los factores de los que dependen los síntomas. Por lo tanto, el objetivo de esta investigación fue determinar las características histológicas del tejido conectivo que se encuentra debajo del puente miocárdico y contribuir a una mejor comprensión de los efectos protectores que este compartimento pasivo podría tener en la prevención de manifestaciones clínicas graves de puente miocárdico. El estudio se llevó a cabo en veinte corazones con puentes miocárdicos. La longitud del puente se determinó utilizando un calibrador electrónico preciso. Se obtuvieron secciones de los puentes miocárdicos con el tejido conjuntivo subyacente y se prepararon para análisis cualitativo y cuantitativo. El tejido conectivo debajo de los puentes estaba compuesto de tejido adiposo y tejido conectivo laxo en diferentes proporciones. El tejido debajo de los puentes delgados estaba predominantemente compuesto de tejido adiposo, mientras que el tejido conectivo laxo era el componente dominante debajo de los puentes gruesos. Los puentes de miocardio tenían un espesor promedio de 0,98 ± 0,44 mm y una longitud promedio de 15,25 ± 5,65 mm. Encontramos una fuerte correlación positiva entre el grosor y la longitud del puente miocárdico (r = 0,860, p = 0,0001). El grosor del compartimiento de tejido conectivo pasivo debajo de los puentes miocárdicos era de 0,58±0,22 mm, y no hubo correlación entre este parámetro y el grosor del puente miocárdico (r = -0,011; p = 0,963). En la evaluación clínica de pacientes con estas anomalías es necesario tener en consideración de forma independiente el grosor y la longitud del puente de miocardio por un lado y el grosor del tejido conectivo que se encuentra debajo del mismo por el otro.

Relationship between perivascular space enlargement and cognitive and motor longitudinal changes in patients with Parkinson′s disease / 中华神经科杂志

Objective:To investigate the correlation between basal ganglia (BG) enlarged perivascular space (EPVS; BG-EPVS) and cognitive and motor longitudinal changes in patients with newly diagnosed Parkinson′s disease and its different motor subtypes [tremor dominant (TD), postural instability and gait disorder (PIGD)].Methods:A total of 131 Parkinson′s disease patients from the Parkinson Progression Markers Initiative (PPMI) database were screened and their clinical data were collected at baseline, 1 year and 2 years of follow-up. The number of EPVS in different brain regions was assessed on axial T 2-weighted images by cranial imaging data, and they were divided into two groups according to the degree of EPVS: BG-EPVS- and BG-EPVS+. Parkinson′s disease patients were divided into TD and PIGD groups by Movement Disorder Society Unified Parkinson′s Disease Rating Scale (MDS-UPDRS) score, and the number and clinical data of EPVS were compared between the two groups, and the correlation between the number and degree of BG-EPVS at baseline and longitudinal changes in clinical outcome measures of Parkinson′s disease and its different motor subtypes (TD, PIGD) was analyzed. Results:BG-EPVS was positively correlated with age ( r=0.32, P<0.01), Hoehn & Yahr stage ( r=0.21, P<0.05), serum neurofilament light chain ( r=0.18, P<0.05) and Epworth Sleepiness Scale score ( r=0.20, P<0.05) in all Parkinson′s disease patients. At baseline and 2 years, the number of BG-EPVS was more in the PIGD group than in the TD group (11.0±4.2 vs 9.0±3.8, t=2.18, P=0.03; 16.3±6.7 vs 12.6±4.6 , t=2.71 , P=0.007;after correction).At baseline, more BG-EPVS in patients with Parkinson′s disease and its motor subtypes (TD, PIGD) was significantly associated with baseline motor outcomes ( β=0.66, P=0.01; β=0.64, P=0.008; β=0.91, P=0.009), but not with cognitive outcomes. By linear mixed effects model analysis, BG-EPVS numbers and moderate to severe BG-EPVS were positively correlated with motor outcomes over time in patients with Parkinson′s disease and its motor subtypes (TD, PIGD) ( β=0.51, P=0.008; β=0.59, P=0.025; β=0.80, P=0.038). After dividing BG-EPVS in Parkinson′s disease patients into different degrees, moderate to severe BG-EPVS was positively correlated with motor outcomes over time ( β=3.30, P=0.031). Conclusion:In this longitudinal study, bigger baseline BG-EPVS numbers were found to be positively associated with longitudinal changes in dyskinesia severity in Parkinson′s disease patients, not with cognitive changes, and be able to predict decline in motor function over a 2-year follow-up period.

Study on imaging features of asymptomatic cerebral small vessel disease and related factors in the elderly population / 中华老年医学杂志

Objective:To investigate the incidence, neuroimaging features, and related factors for asymptomatic cerebral small vessel disease(CSVD)in the elderly population.Methods:A total of 201 elderly people with no neurological disease history who had undergone brain magnetic resonance imaging(MRI)examination from October 2019 to August 2020 were enrolled.We calculated the total CSVD score for each participant based on lacunar infarcts(LIs), white matter hyperintensities(WMH), enlarged perivascular spaces(EPVS), and cerebral microbleeds(CMBs)(0-4 points).CSVD neuroimaging features and the correlation between CSVD markers and clinical variables were analyzed.Results:In this study, 133 cases(66.2%)showed MRI features consistent with CSVD.Of whom, LIs were present in 44(21.9%), high-grade PVWMH in 88(43.8%), high-grade DWMH in 30(14.9%), basal ganglia EPVS in 61(30.3%), and CMBs in 92(45.8%).Total CSVD burden score( OR=1.876, 95% CI: 1.045-3.364, χ2=4.441, P=0.035), PVWMH( OR=2.821, 95% CI: 1.517-5.244, χ2=10.752, P=0.001), DWMH( OR=2.130, 95% CI: 1.108-4.092, χ2=5.145, P=0.023), and EPVS( OR=3.258, 95% CI: 1.675-6.334, χ2=12.129, P=0.000)were associated with hypertension.Total CSVD burden score, PVWMH, DWMH, EPVS, and CMB were correlated with increasing age( P<0.05).LIs was positively correlated with PVWMH( b=0.231, P=0.001), DWMH( b=0.247, P=0.000)and EPVS( b=0.215, P=0.001).There was a positive relationship between PVWMH and DWMH( b=0.546, P=0.000)as well as EPVS( b=0.388, P=0.000).DWMH was also positively correlated with EPVS( b=0.357, P=0.000)and CMB( b=0.177, P=0.009). Conclusions:The incidence of asymptomatic CSVD is high in the elderly population.The total CSVD score is a useful measure to evaluate asymptomatic cerebral small vessel disease in the elderly population.Neuroimaging features of asymptomatic CSVD are mainly correlated with age and hypertension.

Study of mechanism of bone marrow perivascular niche injured by 5-fluorouracil / 中国药理学通报

Aim To investigate the injury of 5-fluorouracil(5-FU)to perivascular hematopoietic niche via isolating mouse bone marrow perivascular mesenchymal progenitor cells in vitro and its related mechanism. Methods The perivascular mesenchymal progenitor cells were isolated from femurs and tibias of C57BL/6J mice with type Ⅱ collagenase and cultured in vitro. Agarose gel electrophoresis was used to detect specific niche genes expression. The viable cells were counted by Trypan blue; the cellular proliferation was detected by CCK-8; the apoptosis was detected by Annexin V/PI double staining, and the cell senescence was detected by β-galactosidase staining. The levels of malondialdehyde(MDA)and superoxide dismutase(SOD)were detected by enzymatic assay. Osteogenic and adipogenic differentiation potential of cells were detected by osteogenic and adipogenic differentiation experiment and osteogenic related genes qRT-PCR assay. The mRNA expression of hematopoietic growth factors was detected by qRT-PCR. Hematopoietic cells were co-cultured with perivascular mesenchymal progenitor cells, and the adhesion molecules and signal molecules between stromal cells and hematopoietic cells were detected, also hematopoietic cell activity, redox indicators and β-galactosidase specific cell senescence were detected. Results 5-FU caused simultaneous apoptosis and senescence of perivascular mesenchymal progenitor cells, inhibited cell proliferation, induced oxidative stress, led to osteogenic/adipogenic differentiation imbalance, and down-regulated the transcription of hematopoietic factors SCF, CXCL12, and G-CSF. For the interaction between stromal cells and hematopoietic cells, the binding effects of VLA-4/VCAM-1, ICAM-1/LFA1 were weakened and TPO/MPL and ANG-1/Tie-2 signals were impaired, leading to oxidative stress of hematopoietic cells and cell senescence. Conclusions 5-FU induces oxidative damage of perivascular mesenchymal progenitor cells and indirectly induces premature senescence of hematopoietic cells.

Clinical diagnosis and treatment of liver perivascular epithelioid cell neoplasms / 中华肝胆外科杂志

Objective:To analyze the clinical features and prognosis of liver perivascular epithelioid cell neoplasms (PEComa).Methods:The clinical data of 12 patients with liver PEComa diagnosed by pathology at the First Affiliated Hospital of Xi 'an Jiaotong University from October 2011 to November 2021 were retrospectively analyzed. There were 1 male and 11 females, with a median age of 44 (range 20 to 63) years old. The clinical manifestations, laboratory examinations, imaging features, treatment methods, postoperative pathological features and treatment outcomes of these patients were collected and analysed. Postoperative follow-up by telephone or patient's follow-up records.Results:Among the 12 patients with hepatic PEComa, 8 patients (66.7%) were asymptomatic and 11 patients (91.7%) had a single lesion. All patients underwent surgical treatment, including local tumor resection in 10 patients (83.3%) and extended hemihepatectomy in 2 patients (16.7%). Enhanced CT showed the lesion to be a quasi-round homogeneous low-density mass, enhanced in arterial phase with hepatic artery branches in the lesion, and decrease in enhancement degrees in portal vein phase and delayed phase. Postoperative pathology of the lesions in all the 12 patients was benign. Immunohistochemical results showed that the positive rates of melanoma cell markers HMB45, Melan-A and smooth muscle actin were 100.0%(12/12), 83.3%(10/12) and 91.7%(11/12) respectively. The median follow-up period was 27 months, and no recurrence or metastasis was found.Conclusion:Hepatic PEComa occurred commonly in women with obscure symptoms. The lesion was mainly single and it had no correlation with hepatitis. It is easily confused with primary liver cancer and liver metastasis on medical imagings. PEComa expressed markers of both melanocyte and smooth muscle cell, and radical surgical resection resulted in good results.

CT, magnetic resonance imaging and clinicopathological characteristics of perivascular epithelioid cell tumor in children / 中华实用儿科临床杂志

Objective:To investigate the CT, magnetic resonance imaging(MRI) and clinicopathological cha-racteristics of perivascular epithelioid cell tumors (PEComas) in children, and improve the diagnostic accuracy of PEComas.Methods:The CT, MRI and clinicopathological characteristics of 6 children confirmed with PEComas by histopathology caming from Beijing Children′s Hospital, Capital Medical University during March 2019 and April 2022 were retrospectively analyzed.Results:The patients aged from 1.7 to 11.9 years old (with mean age of 7.6 years old). The male to female ratio was 1∶2.Of the 6 solitary tumors identified, 2 cases were found in the kidney, 2 cases in the abdominal cavity, 1 case in the pelvic cavity, and 1 case in the groin.The solitary tumors had well-defined borders.Five solitary tumors were shaped like an ellipse and 1 solitary tumor was multinodular-shaped.Lace-like or nodular changes were observed at tumor margins(3 cases). The maximum diameters of the tumors ranged from 4.8 to 15.9 cm (mean value: 9.3 cm). Five tumors showed peripheral invasion and 2 cases had lymph node metastasis.Two patients were complicated with tuberous sclerosis.One case suffered from tumor recurrence after operation.The tumors (6 cases) were isodensity or low density on the plain CT scan, and gradual heterogeneous enhancement was observed after injection of the contrast agent.A majority of the tumors had tortuous (5 cases) and thickened blood vessels inside, and a few of them (2 cases) underwent gravel-like calcification.Patch-like or nodule-like high signal intensity could be seen in the center of the tumors (3 cases) on MRI T1WI and T2WI, while the peripheral part of the lesions showed iso-signal intensity (equal to muscle). On diffusion weighted imaging(DWI) (b=800 s/mm 2), the lesions exhibited restricted diffusion at the peripheral part with significant enhancement, and iso-signal intensity at the central part with none or slight enhancement.Histological classification results revealed that 1 of 6 cases was a benign PEComa and 5 cases were malignant PEComas.The expression rates of Melan-A and SMA were 100.0% and 83.3%, respectively. Conclusions:The CT, MRI and pathological manifestations of PEComas in children have some distinct features.PEComas are often an oval-like mass with clear borders and nodular margins in the abdominal and pelvic cavity, and tortuous and thickened blood vessels can be seen in the tumor.The periphery of the tumor is the main region to be enhanced by the contrast agent.Local invasion and distant metastasis can be observed.Most of the tumors are malignant in pathology.Both melanocyte and muscle cell markers can be found in the expression of immunohistochemistry.

Glymphatic system in Parkinson′s disease / 中华神经科杂志

Parkinson′s disease is a degenerative disease of the central nervous system with abnormal protein deposition in the brain as the main pathological changes. The onset of Parkinson′s disease is related to abnormal deposition protein removal disorders, and the relevant mechanisms are still unclear. The glymphatic system is a metabolic waste and abnormal protein deposition removal system in the brain. In recent years, studies have shown that the changes of aquaporin 4, perivascular space and dural lymphatic vessels in Parkinson′s disease are closely related to the level of relevant pathological proteins in cerebrospinal fluid, leading to the occurrence and development of Parkinson′s disease. The researches on structure and biomarkers of the glymphatic system in Parkinson′s disease in recent years are reviewed in this article.

Dysfunction of lymphatic system and early Parkinson′s disease / 中华神经科杂志

Lymphatic system is the transportation way of cerebrospinal fluid and brain interstitial fluid exchange. And this system is a central nervous drainage system which plays an important role in drainaging and discharging of metabolic waste in the brain. The function of this system can be evaluated indirectly by the perivascular space on magnetic resonance imaging. Parkinson′s disease is a common neurodegenerative disorder. It may be helpful to control the progression of the disease if the changes of perivascular space can be dynamically observed in the early or even prodromal stage of the disease. This article reviews the relationship between lymphatic system disfunction and early stage of Parkinson′s disease.

Microscopic analysis of the myocardial bridges and their relationship with atheromatous plaque / Análisis microscópico de los puentes miocárdicos y su relación con la placa ateromatosa

SUMMARY: Most histopathological studies have reported that the segment of the coronary artery below the myocardial bridge does not present atheromatous plaque, while the segment proximal to the myocardial bridge may have it. The aim of this study was to evaluate the microscopic environment of myocardial bridges. This descriptive study was carried out with 60 hearts of individuals who underwent autopsy at the National Institute of Legal Medicine and Forensic Sciences in Bucaramanga-Colombia. For each specimen, the coronary arteries and their branches were dissected, removing the subepicardial adipose tissue to identify the myocardial bridges and obtain histological sections of the compromised arterial branches. The presence of myocardial bridges was observed in 22 hearts (36.7%) with a length of 17.31 + 4.41 mm and a thickness of 904.57 + 312.27 mm. The coronary vessel caliber at the prepontine level was 246.57 + 49.33 mm and was significantly higher than in the pontine (188.92 + 60.55 mm) and postpontin (190.40 + 47 mm) segments (p=0.001 for both values). Atheromatous plaque was observed in the prepontine segment in 12 cases (46.15 %) and in 8 samples (30.76%) at the pontine level, but in this segment, there was slight damage to the vascular endothelium, or phase I level. The thickness of the tunica intima in the cases with atheromatous plaque was 15.68 + 13.39 mm and that of the plaque-free segments was 5.10 + 4.40 mm (p=0.005), and in the pontine segment the overlying periarterial adipose tissue had a thickness of 72.01 + 69.44 mm, which was higher than the other three locations (p=0.005). The morphometry of the perivascular fat pad and the presence of phase I atheromatous plaque are the main contributions of this study to the histology of myocardial bridges.

RESUMEN: La mayoría de los estudios histopatológicos han reportado que el segmento de la arteria coronaria debajo del puente miocárdico no presenta placa ateromatosa, mientras que el segmento proximal al puente miocárdico puede tenerla. El objetivo de este estudio fue evaluar el entorno microscópico de los puentes miocárdico. Este estudio descriptivo se realizó con 60 corazones de individuos a quienes se les práctico autopsia en el Instituto Nacional de Medicina Legal y Ciencias Forenses de Bucaramanga-Colombia. Para cada espécimen se realizó disección de las arterias coronarias y sus ramas, eliminando el tejido adiposo subepicárdico para identificar los puentes miocárdicos y obtener secciones histológicas de las ramas arteriales comprometidas. Se observó presencia de puentes miocárdicos en 22 corazones (36,7 %) con una longitud de 17.31 + 4.41 mm y un espesor de 904.57 + 312.27 mm. El calibre del vaso coronario a nivel prepontino fue 246.57 + 49.33 mm y fue significativamente mayor que en el segmento pontino (188.92 + 60.55 mm) y pospontino (190.40 + 47 mm) (p=0.001 para ambos valores). Se observó placa ateromatosa en el segmento prepontino en 12 casos (46.15 %) y en 8 muestras (30.76%) al nivel pontino, pero en este segmento, correspondieron a fase I, con ligero daño en el endotelio vascular. El espesor de la túnica íntima en los casos con placa ateromatosa fue de 15.68 + 13.39 mm y de los segmentos libres de placa fue 5.10 + 4.40 mm (p=0.005) y en el segmento pontino el tejido adiposo periarterial suprayacente presento un espesor de 72.01 + 69.44 mm, el cual fue mayor a las otras tres ubicaciones (p=0.005). La morfometría de la almohadilla adiposa perivascular y la presencia de placa ateromatosa en fase I son los principales aportes de este estudio a la histología de los puentes miocárdicos.

A clinical study on 17 patients with liver perivascular epithelioid cell tumors / 中华肝胆外科杂志

Objective:To study the clinical manifestations and prognosis of patients with liver perivascular epithelioid cell tumor (PEComa).Methods:The clinical manifestations, imaging findings, pathological features, treatment and prognosis of 17 patients with liver PEComa managed in Shenzhen People's Hospital from September 2002 to January 2020 were retrospectively analysed.Results:The patient age of onset of liver PEComa was 22 to 54 years (average 34.8 years). There were 13 females and 4 males. 82%(14/17) of patients presented with no significant symptoms. 15/17 had solitary tumors. The diagnostic rate using preoperative B-ultrasound, CT and MRI was low. Postoperative pathological studies showed the tumor cells were mainly epithelioid cells with hyaline or eosinophilic cytoplasm. There were abundant blood vessels in the tumor tissues. Adipose tissues were also seen. Immunohistochemistry showed both HMB45 and Melan-A positivities to arrive at the diagnosis. All patients were treated with surgical resection. There were no recurrence, metastasis, or death on follow-up.Conclusion:Hepatic PEComa occurred more frequently in young women and it had no specific clinical manifestations. Except for a small number of tumors with adipose tissue detected on preoperative imagings, this tumor was difficult to diagnose, or even be suspected on preoperative imagings. Pathological examination combined with immunohistochemistry after surgery established the diagnosis. Surgery resulted in good prognosis.

Correlation between enlarged perivascular spaces and the imaging markers of cerebrovascular disease in patients with ischemic stroke / 中华行为医学与脑科学杂志

Objective:To explore the correlation between enlarged perivascular spaces and other imaging markers of cerebrovascular disease in patients with ischemic stroke.Methods:Totally 287 patients with ischemic stroke hospitalized in neurology department from January 2018 to January 2019 were selected. According to the severity of EPVS in different parts of the brain, the correlations between the severity of EPVS in different parts of the brain and cerebral microbleeds (CMBs), white matter hyperintensity (WMH), lacunar infarcts (LIs) were analyzed. SPSS 22.0 software was used for analysis. Chi-square test, independent sample t-test, rank-sum test and non parametric Mann-Whitney U test were used for group comparison, and Logistic regression analysis was used for multivariate analysis. Results:EPVS was common and severe in patients with ischemic stroke. Periventricular white matter hyperintensity(PWMH)( β=1.604, P<0.001, OR=4.971, 95% CI=2.015-12.263), CMBs ( β=1.224, P=0.018, OR=3.339, 95% CI=1.232-9.383) and LIs ( β=0.626, P=0.047, OR=1.871, 95% CI=1.009-3.470) were independent risk factors for BG-EPVS. PWMH ( r=0.614), DWMH ( r=0.622), LIs ( r=0.532) were positively correlated with the severity of BG-EPVS (all P<0.01). Conclusion:The imaging makers of CSVD are related to BG-EPVS, which can affect the severity of brain BG-EPVS in patients with ischemic stroke.

Discussion on Connotation of "Essence Generating Marrow " Based on Intervention of Guilu Erxian Gum in Perivascular Space of Alzheimer's Disease Patients / 中国实验方剂学杂志

Objective:To study the effect mechanism of Guilu Erxian gum on Alzheimer's disease （AD） from the perspective of regulating perivascular space （PVS），and to explore the scientific connotation of "essence generating marrow". Method:The 80 patients with AD diagnosed by western medicine and kidney deficiency and marrow empty syndrome diagnosed by traditional Chinese medicine were randomly divided into two groups，with 40 cases in each group. Both groups of patients were orally administered with cholinesterase inhibitor Alison，one tablet （5 mg） each time before sleep at night. On this basis，the control group additionally received placebo，while the treatment group was additionally treated with Guilu Erxian gum for 60 days. The Mini-Mental State Examination scale （MMSE）， Wechsler Memory Scale and Activity of Daily Living Scale （ADL） were used before treatment （0 d），as well as 31 d and 61 d after treatment. The number and diameter of PVS in midbrain，basal ganglia，deep insular white matter and semiovale center were counted and their diameters were measured with use of nuclear magnetic resonance imaging （MRI） for head. In addition，the curative effect was evaluated according to MMSE scores on 61 d. Result:There was no significant difference between the two groups 31 d. On 61 d，MMSE and WMS scores increased，while ADL scores decreased as compared with the conditions on 0 d（<italic>P</italic><0.01），and there were significant differences in the three indexes and clinical effective rate between two groups （<italic>P</italic><0.05，<italic>P</italic><0.01） . In addition，there was no significant difference in the number of PVS as compared with the number before treatment and in the comparison between the two groups after treatment，but there was a significant difference in the diameter of PVS（<italic>P</italic><0.01）. Conclusion:Guilu Erxian gum is effective in the treatment of AD，and it can improve the PVS diameter in patients，which may be related to the mechanism of "essence generating marrow ".

Atypical Virchow-Robin SpacesMimicking Cystic Primary Brain Tumor ­ Clinical Report and Literature Review

The Virchow-Robin spaces (VRSs), which are often incidentally observed in modern structural neuroimaging examinations, are small cystic cavities that usually surround the small arteries and arterioles at the level of basal ganglia, the anterior perforated substance and the thalamic-mesencephalic junction. Typically, they have similar physicochemical characteristics to cerebral spinal fluid (CSF) and there is no contrast enhancement on brain CT andMRI images. Its real meaning is unknown, although some contemporary studies have suggested that it might be related to certain traumatic brain injury or several other central nervous system (CNS) disorders, as degenerative diseases. Occasionally, some wide and atypical VRS may be mistaken for primary cystic brain tumors, especially in the context of large and symptomatic lesions, multiple clustered cysts, cortical lesions and if there is adjacent reactive gliosis. The present paper reports four patients who were affected by atypical VRS mimicking brain tumors that required imaging follow-up or even a biopsy to confirm the diagnosis or to indicate the correct approach. Although it is not so unusual, one of them occurred concomitantly and adjacent to a diffuse glioma (co-deleted 1p19q, WHO-GII).

Saphenous vein vasa vasorum as a potential target for perivascular fat-derived factors

Abstract Perivascular adipose tissue (PVAT) is a source of factors affecting vasomotor tone with the potential to play a role in the performance of saphenous vein (SV) bypass grafts. As these factors have been described as having constrictor or relaxant effects, they may be considered either beneficial or detrimental. The close proximity of PVAT to the adventitia provides an environment whereby adipose tissue-derived factors may affect the vasa vasorum, a microvascular network providing the vessel wall with oxygen and nutrients. Since medial ischaemia promotes aspects of graft occlusion the involvement of the PVAT/vasa vasorum axis in vein graft patency should be considered.

Progress of residual inflammatory cardiovascular risk / 医学研究生学报

Coronary artery disease (CAD) remains a leading cause of morbidity and mortality in the world. Although the comprehensive control of cardiovascular disease risk factors has achieved remarkable progress in recent years, the incidence of cardiovascular events is still high after the control of traditional risk factors such as low density lipoprotein cholesterol, blood pressure and blood glucose, collectively referred to as cardiovascular residual risk. Inflammation is a central driver of atherosclerosis and the ultimate rupture of plaque, as well as an important cause of residual cardiovascular risk. Therefore, this article reviews the formation, assessment and treatment of residual inflammatory cardiovascular risk.

Imaging characteristics of pancreatic perivascular epithelioid cell tumor: analysis of 2 cases and literature review / 中华胰腺病杂志

Objective@#To evaluate the imaging and clinicopathological characteristics of pancreas perivascular epithelioid cell tumors (PEComa).@*Methods@#The clinical data of patients with pancreatic PEComa admitted in Changhai Hospital of Navy Medical University from Nov 2013 to Nov 2017 were retrospectively analyzed. Related literature on PEComa were searched and the image and clinicopathological characteristics were investigated.@*Results@#Two pancreatic PEComa patients were admitted in Changhai Hospital. Twenty-nine PEComa patients were reported in previous literature. A total of 31 cases were detected, including 3 men and 27 women. The onset age of the patients ranged from 17-74 years old with a mean of 48 years old. The lesions were located at the pancreatic head and neck in 20 cases, and at the pancreatic body and tail in 11 cases. 27 cases had a single lesion, and 4 cases had multiple lesions. Tumor diameter ranged from 1.0-11.5 cm with a mean of 4.1 cm. The cystic solid of the lesions was recorded in 23 patients, and 18 cases had solid mass. Pancreatic duct dilation was reported in 21 patients and 14 of them did not have pancreatic duct dilation. Enhancement mode of the lesions was examined in 21 patients, and the enhancement degree of the lesions were higher than that of the pancreas in 16 cases.@*Conclusions@#PEComa has a certain imaging characteristic, which could help obtain a preoperative diagnosis.