Cerebral small vessel diseases: cerebral microangiopathies

Engineered inhaled nanocatalytic therapy for ischemic cerebrovascular disease by inducing autophagy of abnormal mitochondria

Mitochondrial dysfunction and subsequent accumulation of reactive oxygen species (ROS) are key contributors to the pathology of ischemic cerebrovascular disease. Therefore, elimination of ROS and damaged mitochondria is crucial for the effective treatment of this disease. For this purpose, we designed an inhalation nanotherapeutic agent, P/D@Mn/Co3O4, to treat ischemic cerebrovascular disease. Mn/Co3O4 effectively removed excess ROS from cells, reduced acute cellular oxidative stress, and protected neural cells from apoptosis. Furthermore, it depleted the H+ surrounding mitochondria and depolarized the mitochondrial membrane potential, inducing mitophagy and eliminating abnormal mitochondria, thereby avoiding the continuous overproduction of ROS by eliminating the source of ROS regeneration. On intranasal administration, Mn/Co3O4 encapsulated by platelet membranes and 2,3-(dioxy propyl)-trimethylammonium chloride can bypass the blood-brain barrier, enter the brain through the trigeminal and olfactory pathways, and target inflammatory regions to remove ROS and damaged mitochondria from the lesion area. In rat models of stroke and vascular dementia, P/D@Mn/Co3O4 effectively inhibited the symptoms of acute and chronic cerebral ischemia by scavenging ROS and damaged mitochondria in the affected area. Our findings indicate that the nanotherapeutic agent developed in this study can be used for the effective treatment of ischemic cerebrovascular disease.

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

YangXue QingNao Wan and Silibinin Capsules, the Two Chinese Medicines, Attenuate Cognitive Impairment in Aged LDLR (+/-) Golden Syrian Hamsters Involving Protection of Blood Brain Barrier

The purpose of the study was to explore the effect and the underlying mechanism of YangXue QingNao Wan (YXQNW) and Silibinin Capsules (SC), the two Chinese medicines, on cognitive impairment in older people with familial hyperlipidaemia. Fourteen month-old female LDLR (+/-) golden Syrian hamsters were used with their wild type as control. YXQNW (0.5 g/kg/day), SC (0.1 g/kg/day), or YXQNW (0.5 g/kg/day) + SC (0.1 g/kg/day) were administrated orally for 30 days. To assess the effects of the two drugs on plasma lipid content and cognitive ability, plasma TC, TG, LDL-C, and HDL-C were measured, and Y maze task was carried out both before and after administration. After administering of the drugs for 30 days, to evaluate the effect of the two drugs on disturbed blood flow caused by hyperlipidemia, the cerebral blood flow (CBF) was measured. To assess blood-brain barrier integrity, albumin leakage in middle cerebral artery (MCA) area was determined. To evaluate the effect of the drugs on impaired microvessels, the number and morphology of microvessels were assessed in hippocampus area. To further evaluate the ultrastructure of microvessels in hippocampus, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were carried out. To assess the profiles of claudin-5 and occludin in hippocampus, we performed immunofluorescence. Finally, to assess the expression of claudin-5, JAM-1, occludin and ZO-1 in hippocampus, western blot was carried out. The results showed that YXQNW, SC, and YXQNW + SC improved cognitive impairment of aged LDLR (+/-) golden Syrian hamsters without lowering plasma TC and LDL-C. YXQNW, SC, and YXQNW + SC attenuated albumin leakage in MCA area and neuronal damage in hippocampus, concomitant with an increase in CBF, a decrease of perivascular edema and an up-regulated expression of claudin-5, occludin and ZO-1. In conclusion, YXQNW, SC, and YXQNW + SC are able to improve cognitive ability in aged LDLR (+/-) golden Syrian hamsters via mechanisms involving maintaining blood-brain barrier integrity. These findings provide evidence suggesting YXQNW or SC as a potential regime to counteract the cognitive impairment caused by familial hypercholesterolemia.

A Postmortem Study of Frontal and Temporal Gyri Thickness and Cell Number in Human Obesity

OBJECTIVE

This study aimed to compare cortex thickness and neuronal cell density in postmortem brain tissue from people with overweight or obesity and normal weight.

METHODS

The cortex thickness and neuron density of eight donors with overweight or obesity (mean = 31.6 kg/m² ; SD = 4.35; n = 8; 6 male) and eight donors with normal weight (mean = 21.8 kg/m² ; SD = 1.5; n = 8; 5 male) were compared. All participants were Mexican and lived in Mexico City. Randomly selected thickness measures of different cortex areas from the frontal and temporal lobes were analyzed based on high-resolution real-size photographs. A histological analysis of systematic-random fields was used to quantify the number of neurons in postmortem left and right of the first, second, and third gyri of frontal and temporal lobe brain samples.

RESULTS

No statistical difference was found in cortical thickness between donors with overweight or obesity and individuals with normal weight. A smaller number of neurons was found among the donors with overweight or obesity than the donors with normal weight at different frontal and temporal areas.

CONCLUSIONS

A lower density of neurons is associated with overweight or obesity. The morphological basis for structural brain changes in obesity requires further investigation.

Neuropathology of cerebrovascular diseases

The chapter describes the epidemiology of cerebrovascular diseases, anatomy of the cerebral blood vessels, pathophysiology of ischemia, hypoxia, hypoxemia, anemic hypoxia, histotoxic hypoxia, carbon monoxide damage, hyperoxid brain damage and decompression sickness, and selective cell and regional vulnerability; diseases of the blood vessels including atherosclerosis, hypertensive angiopathy, small vessel disease, inflammatory vascular diseases, cerebral amyloid angiopathies, CADASIL, CARASIL and other diseases that can lead to cerebrovascular occlusion; intracranial and intraspinal aneurysms and vascular malformations; hematologic disorders that can cause cerebral infarct or hemorrhage; brain ischemic damage; and spontaneous intracranial bleeding. Within ischemic brain damage, focal cerebral ischemia, hemorrhagic infarct, brain edema, penumbra, global cerebral ischemia, venous thrombosis, lacunas and lacunar state, status cribosus, granular atrophy of the cerebral cortex, hippocampal sclerosis, vascular leukoencephalopathy Binswanger type and multi-infarct encephalopathy are discussed in detail. Cognitive impairment of vascular origin deserves an individual section.

Acupuncture with reinforcing and reducing twirling manipulation inhibits hippocampal neuronal apoptosis in spontaneously hypertensive rats

To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats (SHRs), this study used the reinforcing twirling method (1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes), the reducing twirling method (1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes), and the needle retaining method (1.5–2-mm depth and retaining the needle for 10 minutes). Bilateral Taichong (LR3) was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax mRNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax mRNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.

Potential neuroprotection of protodioscin against cerebral ischemia-reperfusion injury in rats through intervening inflammation and apoptosis

The aim of the current research is to investigate the cerebral-protection of protodioscin on a transient cerebral ischemia-reperfusion (I/R) model and to explore its possible underlying mechanisms. The rats were preconditioned with protodioscin at the doses of 25 and 50mgkg(-1) prior to surgery. Then the animals were subjected to right middle cerebral artery occlusion (MCAO) using an intraluminal method by inserting a thread (90min surgery). After the blood flow was restored in 24h via withdrawing the thread, some representative indicators for the cerebral injury were evaluated by various methods including TTC-staining, TUNEL, immunohistochemistry, and Western blotting. As compared with the operated rats without drug intervening, treatment with protodioscin apparently lowered the death rate and improved motor coordination abilities through reducing the deficit scores and cerebral infarct volume. What's more, an apparent decrease in neuron apoptosis detected in hippocampus CA1 and cortex of the ipsilateral hemisphere might attribute to alleviate the increase in Caspase-3 and Bax/Bcl-2 ratio. Meanwhile, concentrations of several main pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) in the serum were also significantly suppressed. Finally, the NF-κB and IκBa protein expressions in the cytoplasm of right injured brain were remarkably up-regulated, while NF-κB in nucleus was down-regulated. Therefore, these observed findings demonstrated that protodioscin appeared to reveal potential neuroprotection against the I/R injury due to its anti-inflammatory and anti-apoptosis properties. This therapeutic effect was probably mediated by the inactivation of NF-κB signal pathways.

Association between Helicobacter pylori Infection and Cerebral Small Vessel Disease

Background

Small vessel disease is an important cause of cerebrovascular diseases and cognitive impairment in the elderly. There have been conflicting results regarding the relationship between Helicobacter pylori infection and ischemic stroke. This study aimed to examine the association between H. pylori infection and cerebral small vessel disease.

Methods

The study included 1,117 patients who underwent brain magnetic resonance imaging and H. pylori identification between 2005 and 2013 at Health Promotion Center, Seoul National University Hospital. Multivariable logistic regression analysis was used to assess the association between H. pylori infection and small vessel disease with adjustment for age, sex, hypertension, diabetes mellitus, dyslipidemia, body mass index, smoking status, problem drinking, and antiplatelet use.

Results

The adjusted odds ratios (aORs) for the association between H. pylori infection and silent brain infarction and cerebral microbleeds were 1.03 (95% confidence interval [CI], 0.66-1.61) and 0.70 (95% CI, 0.38-1.28), respectively. The aORs for silent brain infarction and cerebral microbleeds were 0.81 (95% CI, 0.44-1.44) and 0.59 (95% CI, 0.30-1.18) in patients aged <65 years and 1.59 (95% CI, 0.78-3.22) and 1.89 (95% CI, 0.38-9.33) in those aged >65 years, respectively. Moreover, the aORs for silent brain infarction and cerebral microbleeds were 0.96 (95% CI, 0.54-1.71) and 0.74 (95% CI, 0.33-1.69) in H. pylori-infected patients without atrophic gastritis and 0.89 (95% CI, 0.48-1.62) and 0.99 (95% CI, 0.43-2.27) in those with atrophic gastritis, respectively.

Conclusion

No association between H. pylori infection and small vessel disease was observed. H. pylori-induced inflammation may not be a risk factor for microcirculatory damage in the brain.

Heartsick: psychiatric and inflammatory implications of cerebromicrovascular disease

BACKGROUND

Cerebromicrovascular disease (CMVD) strikes 87% of the population older than 65 years and is linked to an increased risk of ischemic stroke, depression, cognitive impairment, and Alzheimer's disease. Despite the wealth of knowledge on the consequences to the body stemming from poor vascular health, little focus has been placed on the consequences to the brain.

DESIGN

In this review, we present the preclinical and clinical evidence that supports the role of CMVD in behavioral dysfunction, argues for a clinical need for better recognition of the vascular depression phenotype, and calls for a more integrative translational approach to CMVD.

RESULTS AND CONCLUSIONS

Although the concept of cerebrovascular-induced behavioral change has existed for over 100 years, the difficulty of diagnosis, the slow progression of CMVD, and the lack of causative data have led to an underestimation of the patient population and poor treatment strategies. Preclinical studies have focused on the use of microsphere embolic models and vascular inflammation models to assess the mechanisms of, and treatment options for, CMVD. Though preclinical models provide support for correlative data collected in the clinic, translational reciprocity has not been established. The lack of clinical appreciation for the role of cerebrovascular health in brain function may result in missed diagnoses and inadequate treatment of underlying cardiovascular disease. Enhanced recognition of symptoms and disease presentation will allow for earlier prevention, detection, and identification of novel targets for drug development and other intervention strategies.

Smooth muscle cell phenotypic switching in stroke

Disruption of cerebral blood flow after stroke induces cerebral tissue injury through multiple mechanisms that are not yet fully understood. Smooth muscle cells (SMCs) in blood vessel walls play a key role in cerebral blood flow control. Cerebral ischemia triggers these cells to switch to a phenotype that will be either detrimental or beneficial to brain repair. Moreover, SMC can be primarily affected genetically or by toxic metabolic molecules. After stroke, this pathological phenotype has an impact on the incidence, pattern, severity, and outcome of the cerebral ischemic disease. Although little research has been conducted on the pathological role and molecular mechanisms of SMC in cerebrovascular ischemic diseases, some therapeutic targets have already been identified and could be considered for further pharmacological development. We examine these different aspects in this review.

Long-Term Stimulation with Electroacupuncture at DU20 and ST36 Rescues Hippocampal Neuron through Attenuating Cerebral Blood Flow in Spontaneously Hypertensive Rats

This study was designed to investigate the effect of long-term electroacupuncture at Baihui (DU20) and Zusanli (ST36) on cerebral microvessels and neurons in CA1 region of hippocampus in spontaneously hypertensive rats (SHR). A total of 45 male Wistar rats and 45 SHR were randomly grouped, with or without electroacupuncture (EA) at DU20 and ST36, once every other day for a period of 8 weeks. The mean arterial pressure (MAP) was measured once every 2 weeks. Cerebral blood flow (CBF) and the number of open microvessels in hippocampal CA1 region were detected by Laser Doppler and immunohistochemistry, respectively. Nissl staining and Western blotting were performed, respectively, to determine hippocampus morphology and proteins that were implicated in the concerning signaling pathways. The results showed that the MAP in SHR increased linearly over the observation period and was significantly reduced following electroacupuncture as compared with sham control SHR rats, while no difference was observed in Wistar rats between EA and sham control. The CBF, learning and memory capacity, and capillary rarefaction of SHR were improved by EA. The upregulation of angiotensin II type I receptor (AT1R), endothelin receptor (ETAR), and endothelin-1 (ET-1) in SHR rats was attenuated by electroacupuncture, suggesting an implication of AT1R, ETAR, and ET-1 pathway in the effect of EA.

MRI in multiple sclerosis

Over the past 2 decades, MRI has been integrated into the diagnosis of multiple sclerosis (MS), the study of MS pathobiology, and the development and monitoring of MS treatments. This integration has irrevocably changed the way we think about the disease. New treatments, advanced through early stages of development using MRI outcome measures, have revolutionized the treatment of MS. Although MS remains a clinical diagnosis, conventional MRI is now a requisite adjunct to that diagnosis. Early in the disease, MRI monitoring of a patient on immunomodulatory therapy is helpful in identifying breakthrough disease activity that may predict long-term outcome. Advanced MRI technologies, although currently relegated to the research realm, are improving the detection of previously underappreciated aspects of MS pathology and may help lead to the evaluation of new therapeutic strategies.

Cognitive impairment of vascular origin: neuropathology of cognitive impairment of vascular origin

The term cognitive impairment of vascular origin is used to designate global cognitive deficits as well as focal neurological deficits such as aphasia, apraxia and agnosia of vascular/circulatory origin. It has been useful for identifying early clinical and neuroradiological alterations that might permit therapeutic strategies geared to curbing the progression of cerebrovascular disease. Multi-infarct encephalopathy, infarcts in strategic areas, lacunae and lacunar status, Binswanger's encephalopathy, hippocampal sclerosis, cortical granular atrophy and watershed infarcts are common lesions. Hypertension and vascular diseases such as arteriosclerosis, small blood vessel disease, inflammatory diseases of the blood vessels, Sneddon syndrome, cerebral amyloid angiopathies, cerebral autosomic dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and Maeda's syndrome are causative of cognitive impairment of vascular origin. Other less common causes are hereditary endotheliopathy with retinopathy, neuropathy and strokes (HERNS), cerebro-retinian vasculopathy (CRV), hereditary vascular retinopathy (HVR) (all three linked to 3p21.1-p21.3), hereditary infantile hemiparesis with arteriolar retinopathy and leukoencephalopathy (HIHRATL) (not linked to 3p21), fibromuscular dysplasia, and moya-moya disease. Lack of uniformity of clinical manifestations, the variety of vascular diseases and circulatory factors, the diverse, but often convergent, neuropathological substrates, and the common association with unrelated neurodegenerative diseases in the elderly, make it hard to assume a single clinical approach in the diagnosis and treatment of cognitive impairment of vascular origin. Rather, environmental and genetic risk factors, underlying vascular diseases, associated systemic, metabolic and neurodegenerative diseases and identification of extent and distribution of lesions with morphological and functional neuroimaging methods should be applied in every individual patient.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy: a genetic cause of cerebral small vessel disease

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a single-gene disorder of the cerebral small blood vessels caused by mutations in the Notch3 gene. The exact prevalence of this disorder was unknown currently, and the number of reported CADASIL families is steadily increasing as the clinical picture and diagnostic examinations are becoming more widely known. The main clinical manifestations are recurrent stroke, migraine, psychiatric symptoms, and progressive cognitive impairment. The clinical course of CADASIL is highly variable, even within families. The involvement of the anterior temporal lobe and the external capsule on brain magnetic resonance imaging was found to have high sensitivity and specificity in differentiating CADASIL from the much more common sporadic cerebral small-vessel disease (SVD). The pathologic hallmark of the disease is the presence of granular osmiophilic material in the walls of affected vessels. CADASIL is a prototype single-gene disorder that has evolved as a unique model for studying the mechanisms underlying cerebral SVD. At present, the incidence and prevalence of CADASIL seem to be underestimated due to limitations in clinical, neuroradiological, and genetic diagnoses of this disorder.

Cerebrovascular dysfunction and microcirculation rarefaction precede white matter lesions in a mouse genetic model of cerebral ischemic small vessel disease

Cerebral ischemic small vessel disease (SVD) is the leading cause of vascular dementia and a major contributor to stroke in humans. Dominant mutations in NOTCH3 cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a genetic archetype of cerebral ischemic SVD. Progress toward understanding the pathogenesis of this disease and developing effective therapies has been hampered by the lack of a good animal model. Here, we report the development of a mouse model for CADASIL via the introduction of a CADASIL-causing Notch3 point mutation into a large P1-derived artificial chromosome (PAC). In vivo expression of the mutated PAC transgene in the mouse reproduced the endogenous Notch3 expression pattern and main pathological features of CADASIL, including Notch3 extracellular domain aggregates and granular osmiophilic material (GOM) deposits in brain vessels, progressive white matter damage, and reduced cerebral blood flow. Mutant mice displayed attenuated myogenic responses and reduced caliber of brain arteries as well as impaired cerebrovascular autoregulation and functional hyperemia. Further, we identified a substantial reduction of white matter capillary density. These neuropathological changes occurred in the absence of either histologically detectable alterations in cerebral artery structure or blood-brain barrier breakdown. These studies provide in vivo evidence for cerebrovascular dysfunction and microcirculatory failure as key contributors to hypoperfusion and white matter damage in this genetic model of ischemic SVD.

Notch: from neural development to neurological disorders

Notch is an integral membrane protein that functions as receptor for ligands such as jagged and delta that are associated with the surface of neighboring cells. Upon ligand binding, notch is proteolytically cleaved within its transmembrane domain by presenilin-1 (the enzymatic component of the gamma-secretase complex) resulting in the release of a notch intracellular domain which translocates to the nucleus where it regulates gene expression. Notch signaling plays multiple roles in the development of the CNS including regulating neural stem cell (NSC) proliferation, survival, self-renewal and differentiation. Notch is also present in post-mitotic neurons in the adult CNS wherein its activation influences structural and functional plasticity including processes involved in learning and memory. Recent findings suggest that notch signaling in neurons, glia, and NSCs may be involved in pathological changes that occur in disorders such as stroke, Alzheimer's disease and CNS tumors. Studies of animal models suggest the potential of agents that target notch signaling as therapeutic interventions for several different CNS disorders.

Speech and language disorders secondary to diffuse subcortical vascular lesions: Neurolinguistic and acoustic analysis. A case report

BACKGROUND AND PURPOSE

Subcortical white matter (WM) plays an important role in speech production and language processing. Most frequently, cerebral WM lesions are secondary to small vessel disease in patients with vascular risk factors. We report the case of a 53-year-old man with history of hypertension and ischemic subcortical lesions, who presented with speech difficulties and mild cognitive impairment.

METHODS

Language and cognitive assessment included Boston Diagnostic Aphasia Examination, Boston Naming Test, Rey Auditory-Verbal Learning Test, Rey-Osterrieth Complex Figure Test, Trail Making Test A and B, Wisconsin Card Sorting Test, Scale for Evaluation of Perceptive Characteristics of Voice and Speech, and Multidimensional Evaluation of Speech and Voice.

RESULTS

Brain MRI showed ischemic WM lesions and lacunar infarcts in the brainstem and right cerebellum. Cognitive testing revealed mild cognitive impairment, predominantly affecting attention and executive functions. Speech and language analysis demonstrated dysarthria, dysphonia with hypophonia, and imprecise articulation, as well as short rushes of speech, palilalia and mild subcortical dysphasia.

CONCLUSIONS

Neurolinguistic and acoustic analysis in patients with ischemic WM lesions can provide additional information in the understanding of language and speech disturbances, and can assist in patient management.

Invited article: an MRI-based approach to the diagnosis of white matter disorders

BACKGROUND

There are many different white matter disorders, both inherited and acquired, and consequently the diagnostic process is difficult. Establishing a specific diagnosis is often delayed at great emotional and financial costs. The pattern of brain structures involved, as visualized by MRI, has proven to often have a high diagnostic specificity.

METHODS

We developed a comprehensive practical algorithm that relies mainly on the characteristics of brain MRI.

RESULTS

The initial decision point defines a hypomyelination pattern, in which the cerebral white matter is hyperintense (normal), isointense, or slightly hypointense relative to the cortex on T1-weighted images, vs other pathologies with more prominent hypointensity of the cerebral white matter on T1-weighted images. In all types of pathology, the affected white matter is hyperintense on T2-weighted images, but, as a rule, the T2 hyperintensity is less marked in hypomyelination than in other pathologies. Some hypomyelinating disorders are typically associated with peripheral nerve involvement, while others are not. Lesions in patients with pathologies other than hypomyelination can be either confluent or isolated and multifocal. Among the diseases with confluent lesions, the distribution of the abnormalities is of high diagnostic value. Additional MRI features, such as white matter rarefaction, the presence of cysts, contrast enhancement, and the presence of calcifications, further narrow the diagnostic possibilities.

CONCLUSION

Application of a systematic decision tree in MRI of white matter disorders facilitates the diagnosis of specific etiologic entities.

MRI features of pontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL)

BACKGROUND AND PURPOSE

Cerebral small vessel disease is a topic of growing interest for both the scientific community and the aging society. We report the magnetic resonance imaging (MRI) characteristics of a recently found autosomal dominantly inherited microangiopathy.

METHODS

Eighteen members (35 to 77 years) of a large German family underwent MR scanning with a standardized MRI protocol for cerebrovascular diseases. Images were evaluated independently by two neuroradiologists.

RESULTS

Six family members revealed an unequivocally pathological phenotype on MRI with lacunar infarcts of the pons (6/6) and lesions of the subcortical and periventricular white matter (5/6). Lesions in the temporal lobes (1/6) and cerebral microbleeds (1/6) were uncommon. None of the patients revealed atherosclerotic changes in MR angiography. Retrospective analysis of 5 brain autopsies from previously reported patients of the same family confirmed the regular involvement of the pons.

CONCLUSION

This cerebral autosomal dominant arteriopathy with pontine infarcts and leukoencephalopathy is characterized by a special lesion pattern strikingly different from CADASIL. The distinct MRI characteristics with pontine lesions and rare occurrence of temporal lesions argue for a new nosological entity and may be helpful for the differential diagnosis.

Cerebral microbleeds: old leaks and new haemorrhages

Black dots in the brain parenchyma diagnosed in T2(*)-weighted magnetic resonance imaging should be interpreted in light of the patient's history as well as the location, number and distribution of the lesions and associated imaging findings. These dots will correspond to haemoglobin degradation products in most of the cases referred to as cerebral microbleeds in patients with small vessel disease. Cerebral microbleeds have a prevalence of 5.7% (range 3.7-7.7%) and are observed more frequently with increasing age. cerebral microbleeds have been observed in 47-80% of the primary intracerebral haemorrhage patients and in 0-78% of the patients with ischaemic cerebrovascular disease and appear to be a general marker of various types of bleeding-prone, small vessel disease and a predictor of recurrent vascular events. The occurrence and the number of cerebral microbleeds are associated with the degree of cerebral white matter abnormalities. Current data does not support the hypothesis that cerebral microbleeds are associated with a higher risk for a clinically relevant intracerebral haemorrhage, after anticoagulation/antiaggregation therapy, or after thrombolytic therapy in stroke patients. Therefore, the current data do not support the general exclusion of patients from therapy based on the presence of cerebral microbleeds. In the future, cerebral microbleeds may be incorporated into the design of clinical trials of anticoagulation/antiaggregation drugs in stroke patients for potential individual stratification for both the risk of recurrent ischaemic stroke and for the risk of intracerebral haemorrhage.

Vascular cognitive impairment

Cognitive impairment commonly accompanies clinical syndromes associated with vascular disease of the brain. Because of evolving definitional criteria, however, the frequency of cognitive impairment attributable to cerebrovascular disease is difficult to determine. Dementia occurs in up to one-third of elderly patients with stroke, a subset of whom have Alzheimer's disease (AD) rather than a pure vascular dementia syndrome. In fact, pure vascular dementia has been shown to be uncommon in most large autopsy series. A mixed etiology of AD and cerebrovascular disease is thought to become more common with increasing age, although no clinical criteria for the diagnosis of AD with cerebrovascular disease are currently available. Epidemiological studies have implicated subcortical small-vessel disease as a risk factor for cognitive impairment and dementia, but the cognitive expression and clinical significance of MRI white matter changes in individual patients is difficult to establish. The frequency of specific neuropathologic features of vascular cognitive impairment depends largely on study inclusion criteria. Cerebral meningocortical microangiopathies with distinctive clinicopathological profiles are associated with dementia in both sporadic cases and familial syndromes. In patients with AD, the contribution of amyloid-beta protein to the degree of cognitive impairment has not been clearly defined.

ACE I/D polymorphism in different etiologies of ischemic stroke

OBJECTIVES

Data concerning an association between angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and ischemic stroke (IS) remain inconsistent. Results of some studies suggest that DD genotype may be a risk factor for small vessel disease (SVD) stroke. Here, we investigated whether this polymorphism is associated with IS of different etiologies in a Polish population.

SUBJECTS AND METHODS

Ischemic stroke etiology was established according to the TOAST criteria. We studied 92 stroke patients with large vessel disease and their 184 matched controls; 96 stroke patients with SVD and 192 controls; 180 patients with cardioembolic stroke (CE) and 180 controls. ACE I/D polymorphism was determined using the polymerase chain reaction method.

RESULTS

The distribution of ACE genotypes and alleles was essentially the same in all analyzed IS subtypes and their matched controls.

CONCLUSIONS

We failed to find an association between ACE polymorphism and etiological subtypes of IS in a Polish population.

The Role of Conventional MR and CT in the Work-Up of Dementia Patients

Dementia is a clinical syndrome with many causes. There often is overlap in the clinical manifestations of various forms of dementia, making them difficult to categorize. Neuroimaging can play an important role in distinguishing one form of dementia from another. Advanced imaging techniques continue to provide greater insight into the underlying pathologic processes in patients who have dementia. Conventional MRI and CT, however, still can contribute useful information when interpreting radiologists are familiar with the patterns of volume loss and signal or density changes that are characteristic of various forms of dementia.

Cerebral small vessel diseases: manifestations in young women

PURPOSE OF REVIEW

Cerebral small vessel diseases are responsible for 20-30% of ischemic strokes as well as for a considerable proportion of cerebral hemorrhages and encephalopathies. Less known than the manifestations in old age are those in young women comprising posterior encephalopathy and Susac's syndrome.

RECENT FINDINGS

Magnetic resonance imaging has allowed us to identify posterior encephalopathy, characterized by headache, seizures, visual disturbances and hypertension, as a frequent complication of preeclampsia/eclampsia syndrome in the perinatal and postpartum period. Magnetic resonance findings are pathognomonic with bilateral cortical-subcortical lesions in the posterior hemispheres typically sparing the calcarine fissure. Conversely, white matter lesions on magnetic resonance imaging particularly involving the corpus callosum, and a (subclinical) sensorineural hearing loss are diagnostic of the retinocochleocerebral vasculopathy called Susac's syndrome.

SUMMARY

Posterior encephalopathy can also follow from a broad spectrum of endotheliotoxic conditions like chemotherapy, immunosuppression and sepsis. Early recognition of the disorder is decisive for a benign outcome since therapy consists of removal of precipitating factors, lowering of blood pressure and treatment with magnesium sulfate. The retinocochleocerebral vasculopathy appears to be underdiagnosed. An autoimmune-mediated arteriolopathy is presumed and the disease is nearly always monophasic. A variety of therapeutic approaches have been recommended, none of which, however, is based on anything other than anecdotal evidence.

The role of conventional MR and CT in the work-up of dementia patients

Neuroimaging can play an important role in distinguishing one form of dementia from another. Advanced imaging techniques continue to provide greater insight into the underlying pathologic processes in patients who have dementia. Conventional MRI and CT, however, can contribute useful information when interpreting radiologists are familiar with the patterns of volume loss and signal or density changes that are characteristic of various forms of dementia.

A Chronic Fatigue Syndrome - related proteome in human cerebrospinal fluid

BACKGROUND

Chronic Fatigue Syndrome (CFS), Persian Gulf War Illness (PGI), and fibromyalgia are overlapping symptom complexes without objective markers or known pathophysiology. Neurological dysfunction is common. We assessed cerebrospinal fluid to find proteins that were differentially expressed in this CFS-spectrum of illnesses compared to control subjects.

METHODS

Cerebrospinal fluid specimens from 10 CFS, 10 PGI, and 10 control subjects (50 mul/subject) were pooled into one sample per group (cohort 1). Cohort 2 of 12 control and 9 CFS subjects had their fluids (200 mul/subject) assessed individually. After trypsin digestion, peptides were analyzed by capillary chromatography, quadrupole-time-of-flight mass spectrometry, peptide sequencing, bioinformatic protein identification, and statistical analysis.

RESULTS

Pooled CFS and PGI samples shared 20 proteins that were not detectable in the pooled control sample (cohort 1 CFS-related proteome). Multilogistic regression analysis (GLM) of cohort 2 detected 10 proteins that were shared by CFS individuals and the cohort 1 CFS-related proteome, but were not detected in control samples. Detection of >or=1 of a select set of 5 CFS-related proteins predicted CFS status with 80% concordance (logistic model). The proteins were alpha-1-macroglobulin, amyloid precursor-like protein 1, keratin 16, orosomucoid 2 and pigment epithelium-derived factor. Overall, 62 of 115 proteins were newly described.

CONCLUSION

This pilot study detected an identical set of central nervous system, innate immune and amyloidogenic proteins in cerebrospinal fluids from two independent cohorts of subjects with overlapping CFS, PGI and fibromyalgia. Although syndrome names and definitions were different, the proteome and presumed pathological mechanism(s) may be shared.

Mechanisms of target organ damage caused by hypertension: therapeutic potential

Hypertension is a major risk factor for cardiovascular mortality and morbidity through its effects on target organs like the brain, heart, and kidney. Structural alterations in the microcirculation form a major link between hypertension and target organ damage. In this review, we describe damages related to hypertension in these target organs and the mechanisms involved in the pathogenesis of hypertension-induced cardiovascular diseases such as dementia, cardiac ischemia and remodeling, or nephropathy. We also focus on the therapeutical potential on the basis of such mechanisms. Several antihypertensive agents like diuretics, angiotensin converting enzyme (ACE) inhibitors, angiotensin II (Ang II) receptor antagonists, beta-blockers, or calcium channel blockers (CCBs) have been shown to reduce effectively hypertension associated cardiovascular events and to improve end organ damage. More recently, aldosterone antagonism has also shown beneficial effects. Part of the favorable effects of these agents is due to blood pressure lowering as such. Other mechanisms such as oxidative stress, inflammation, or endothelial dysfunction have appeared to play a key role in the pathogenesis of target organ damage and therefore represent another important pathway for therapy. In this review, we discuss the different therapeutic approaches aiming at reducing cardiovascular events and damages induced by hypertension.