VE-cadherin in arachnoid and pia mater cells serves as a suitable landmark for in vivo imaging of CNS immune surveillance and inflammation

Meninges cover the surface of the brain and spinal cord and contribute to protection and immune surveillance of the central nervous system (CNS). How the meningeal layers establish CNS compartments with different accessibility to immune cells and immune mediators is, however, not well understood. Here, using 2-photon imaging in female transgenic reporter mice, we describe VE-cadherin at intercellular junctions of arachnoid and pia mater cells that form the leptomeninges and border the subarachnoid space (SAS) filled with cerebrospinal fluid (CSF). VE-cadherin expression also marked a layer of Prox1+ cells located within the arachnoid beneath and separate from E-cadherin+ arachnoid barrier cells. In vivo imaging of the spinal cord and brain in female VE-cadherin-GFP reporter mice allowed for direct observation of accessibility of CSF derived tracers and T cells into the SAS bordered by the arachnoid and pia mater during health and neuroinflammation, and detection of volume changes of the SAS during CNS pathology. Together, the findings identified VE-cadherin as an informative landmark for in vivo imaging of the leptomeninges that can be used to visualize the borders of the SAS and thus potential barrier properties of the leptomeninges in controlling access of immune mediators and immune cells into the CNS during health and neuroinflammation.

Antigen recognition detains CD8+ T cells at the blood-brain barrier and contributes to its breakdown

Blood-brain barrier (BBB) breakdown and immune cell infiltration into the central nervous system (CNS) are early hallmarks of multiple sclerosis (MS). High numbers of CD8+ T cells are found in MS lesions, and antigen (Ag) presentation at the BBB has been proposed to promote CD8+ T cell entry into the CNS. Here, we show that brain endothelial cells process and cross-present Ag, leading to effector CD8+ T cell differentiation. Under physiological flow in vitro, endothelial Ag presentation prevented CD8+ T cell crawling and diapedesis resulting in brain endothelial cell apoptosis and BBB breakdown. Brain endothelial Ag presentation in vivo was limited due to Ag uptake by CNS-resident macrophages but still reduced motility of Ag-specific CD8+ T cells within CNS microvessels. MHC class I-restricted Ag presentation at the BBB during neuroinflammation thus prohibits CD8+ T cell entry into the CNS and triggers CD8+ T cell-mediated focal BBB breakdown.

Comparison of leg dynamic models for quadrupedal robots with compliant backbone

Many quadrupeds are capable of power efficient gaits, especially trot and gallop, thanks to their flexible trunk. The oscillations of the system that includes the backbone, the tendons and musculature, store and release elastic energy, helping a smooth deceleration and a fast acceleration of the hindquarters and forequarters, which improves the dynamics of running and its energy efficiency. Forelegs and hindlegs play a key role in generating the bending moment in the trunk. In this paper we present our studies aimed at modeling and reproducing such phenomena for efficient quadrupedal robot locomotion. We propose a model, called mass-mass-spring model, that overcomes the limitation of existing models, and demonstrate that it allows studying how the masses of the legs generate a flexing force that helps the natural bending of the trunk during gallop. We apply our model to six animals, that adopt two different galloping patterns (called transverse and rotatory), and compare their energy efficiency.

Complementarity between microhistological analysis and PCR-capillary electrophoresis in diet analysis of goats and cattle using faecal samples

An evaluation is made of the complementarity between two non-invasive techniques, cuticle microhistological analysis (CMA) and PCR-capillary electrophoresis (PCR-CE) DNA-based analysis, for the determination of herbivore diet composition from faecal samples. Cuticle microhistological analysis is based on the different microanatomical characteristics of the epidermal fragments remaining in the faeces. The PCR-CE technique combines PCR amplification of a trnL(UAA) genomic DNA region with amplicon length determination by CE, with this length being characteristic for each species or taxon. A total of 37 fresh stool samples were analyzed, including 16 from feral goats (Capra hircus) from the Tramuntana mountain range (Mallorca, Baleares) and 11 from Bruna dels Pirineus cattle breed (Bos taurus) from the surrounding Montserrat mountain range (Barcelona, Spain). All the animals were in a free grazing Mediterranean pine habitat, dominated by Aleppo pine (Pinus halepensis). The results showed that both techniques detected a similar number of plant components in the faeces of goats and cows. In the case of goats, a positive correlation was obtained between the percentage of samples in which a particular taxon is detected by CMA and the percentage of samples in which that taxon is detected by PCR-CE. This correlation was not observed in the case of cows. It is concluded that PCR-CE is a fast and reliable method to detect the different plant components in the faeces of herbivores. However, it cannot be considered as an alternative to CMA, but as a complementary method, since both techniques can detect some taxa that are not detected by the other technique. In addition, CMA detected the presence of the different taxa in a greater number of samples, and at the same time, it enables quantitative data to be obtained for plant diet composition. The species of herbivore also seems to influence the results obtained by PCR-CE, so more studies are required to address this aspect.

Effects of boom and bust grazing management on vegetation and health of beef cattle used for wildfire prevention in a Mediterranean forest

Humans and wildfires have historically driven landscape structure in the Mediterranean basin. The Iberian Peninsula is not an exception to that rule, and therefore, farmers, researchers, and governments seek alternative tools to minimize the loss of biodiversity and wildfire risks. Extensive livestock including beef cattle is currently promoted as a suitable management tool by European agro-environmental policies yet pieces of evidence exist regarding the reciprocal effects between cows and Mediterranean woody vegetation. In this work, we performed a field manipulation to evaluate whether free-ranging beef cattle without supplementary feeding, at high density (2 livestock units (LU)/ha) for a short period of time i.e. "boom and bust grazing" management, are able to adapt their grazing preferences to the Mediterranean woody vegetation without health impairment, and prevent from bush encroachment and wildfires. For our purposes, a native herd of 14 adult cows was kept captive without supplementary feeding in a 14 ha enclosure covered by Mediterranean vegetation for two months (April-June 2016). Plant and cattle fecal and blood samples were collected to assess diet composition (plant cuticle microhistological analysis), fecal nitrogen and protein contents of consumed plants, and the nutritional status (non-esterified fatty acids) of cattle. Our results showed that cattle adapted their feeding habits toward a more woody diet including potentially flammable taxa but with some detrimental effects on health status. Hence, cattle cannot control woody vegetation for long periods of time without supplementary feeding. Further research should be oriented to explore other alternative approaches to minimize the health impairment of cattle used for control flammable vegetation in Mediterranean regions.

Iris Melanocytoma Mimicking the Cogan-Reese Syndrome with Monocular Pigment Dissemination

PURPOSE

To report a case of iris melanocytoma mimicking the Cogan-Reese syndrome.

METHODS

A 37-year-old woman presented with pigmentary glaucoma in her left eye. There was diffuse pigmentary dispersion in the anterior segment, pedunculated pigmented nodules on the anterior iris surface, mild iris atrophy, and ectropion iridis. Neither intrinsic vasculature nor a sector cataract was found. The angle was open with marked trabecular pigmentation and no anterior synechiae. The intraocular pressure was 30 mmHg with maximum medical treatment and there was glaucomatous optic atrophy. The differential diagnosis included iris pigmented tumor and iridocorneal endothelial syndrome (Cogan-Reese syndrome). An iris biopsy was performed for diagnostic purposes.

RESULTS

Histologic diagnosis after evaluation of the specimen was iris melanocytoma.

CONCLUSIONS

This case presents signs considered quasi-pathognomonic of iridocorneal endothelial syndrome (Cogan-Reese syndrome): glaucoma, mild iris atrophy associated with pedunculated iris nodules, and ectropion iridis. Therefore, iris melanocytoma can present with features that mimic the Cogan-Reese syndrome.

Bilateral Non-Simultaneous Optic Neuropathy and Unilateral Macular Edema in a Patient with Poems Syndrome

Purpose

To report a case of bilateral non-simultaneous optic neuropathy and unilateral macular edema in a patient with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome.

Methods

A 61-year-old man with POEMS syndrome had bilateral anterior optic neuropathy and unilateral macular edema.

Results

Visual field testing showed bilateral superior altitudinal field defect. Fluorescein angiography revealed unilateral pooling of fluid consistent with cystoid macular edema. Optical coherence tomography (OCT) showed bilateral loss of retinal nerve fiber layer thickness. The erythrocyte sedimentation rate and C-reactive protein values were normal. The serum vascular growth factor measurement was elevated.

Conclusions

This is the first reported case of ophthalmoscopic, angiographic, and OCT evidence of non-simultaneous optic neuropathy and macular edema in this syndrome. The increased vascular permeability could explain all these factors.

[Persistent corneal defects treated with botulinum toxin-induced ptosis]

OBJECTIVES

To evaluate the use of botulinum toxin (BTX) induced ptosis in the treatment of corneal pathology.

METHODS

We employed two BTX injections into the superior lid of 10 eyes (9 patients). We evaluated the degree of ptosis, its duration and the effect on the corneal lesion.

RESULTS

Complete ptosis resulted in seven eyes and the corneal pathology resolved in all of them. There were no relevant complications.

CONCLUSIONS

BTX treatment is a simple and safe technique for treating refractory corneal pathology. It has significant advantages over surgical tarsorrhaphy and is especially useful where the pathology does not require surgery.

[Acute retinal necrosis syndrome following chickenpox]

CASE REPORT

A 34-year-old male patient developed acute retinal necrosis in his left eye about three weeks after the onset of chickenpox. Systemic antiviral treatment with intravenous acyclovir (10 mg/kg/8 hours) and systemic corticosteroids (1 mg/kg/day) controlled the retinitis and the patient suffered no loss of visual acuity.

DISCUSSION

Acute retinal necrosis is an unusual complication of chickenpox. A mild form of this entity has been described during the course of primary varicella-zoster infection. Adequate and early therapy during the acute phase of the disease with intravenous acyclovir and systemic corticosteroids is recommended to achieve a satisfactory visual acuity and prevent complications.

[Juxtapapillary capillary hemangioma and central serous retinopathy: description of a case with spontaneous resolution]

CASE REPORT

A patient presented with a unilateral decrease of visual acuity and was found to have a juxtapapillary capillary hemangioma by ophthalmoscopy (confirmed by fluorescein angiography) and atrophy in the retinal pigmentary epithelium with leakage points suggesting bilateral central serous retinopathy. Spontaneous resolution of the hemangioma, as well as the central serous retinopathy, subsequently occurred.

DISCUSSION

The decrease of visual acuity in a patient with a juxtapapillary capillary hemangioma has been associated with complications from the lesion itself, but an association of central serous retinopathy, as a possible predisposing factor, has not been previously described.

Cryopreservation of murine embryos, human spermatozoa and embryonic stem cells using a liquid nitrogen-free, controlled rate freezer

A Stirling Cycle Cryocooler has been developed as an alternative to conventional liquid nitrogen controlled rate freezers. Unlike liquid nitrogen systems, the Stirling Cycle freezer does not pose a contamination risk, can be used in sterile conditions and has no need for a constant supply of cryogen. Three types of samples from two species (murine embryos, human spermatozoa and embryonic stem cells), each requiring different cooling protocols, were cryopreserved in the Stirling Cycle freezer. For comparison, cells were also frozen in a conventional liquid nitrogen controlled rate freezer. Upon thawing, the rates of survival of viable cells were generally greater than 50% for mouse embryos and human embryonic stem cells, based on morphology (mouse embryos) and staining and colony formation (human embryonic stem cells). Survival rates of human spermatozoa frozen in the Stirling Cycle freezer, based on motility and dead cell staining, were similar to those of samples frozen in a conventional controlled rate freezer using liquid nitrogen.

[Prevalence of multiple sclerosis in Colombia]

INTRODUCTION

Multiple sclerosis (MS) is the commonest demyelinating condition of the nervous system. It is characterized by numerous demyelinating areas or plaques of demyelination which are found dispersed throughout the nervous system. It has been shown that MS is less frequent in tropical regions than in subtropical regions. In Latin America particularly, there are some studies which show this phenomenon. However, in Colombia no studies of prevalence of MS have been done.

OBJECTIVE

To determine the prevalence of multiple sclerosis in five provinces of Colombia (Antioquia, Caldas, Santander, Risaralda and Bolivar).

PATIENTS AND METHODS

The capture-recapture method was used for two sources to determine the number of cases defined on the criteria of Poser et al seen between July 1995 and June 2000.

RESULTS

The prevalence (cases of MS per 100,000 inhabitants) varied between 1.48 in Antioquia (95% CI 1.12; 1.78) and 4.98 in Risaralda (95% CI 3.52; 6.43). Seventy two percent were women. The regions included in this study represented 25% of the population of Colombia.

CONCLUSIONS

There is a low prevalence of MS which is as expected in tropical areas. Persons with MS in these regions may be very useful in the study of other factors involved in the aetiology of MS (genetic). The capture-recapture method is an excellent tool for carrying out prevalence studies since it is cheap and requires little time.

Influence of exhaustive treadmill exercise on cognitive functioning in chronic fatigue syndrome

The purpose of this study was to determine the effect of exhaustive exercise on cognitive performance of patients with chronic fatigue syndrome (CFS) and sedentary healthy controls (CON). Subjects were 19 women with CFS and 20 CON. A test battery consisting of 4 cognitive tests (CTB) was given pre-, immediately post-, and 24 hours post-treadmill exercise to exhaustion. No differences were seen on the CTB pre-exercise. CFS patients improved at a slower rate than CON on the Symbol Digit Modalities Test (SDMT), Stroop Word Test (SWT), and Stroop Color Test (SCT). When compared with CON, a lower number of correct responses was seen for the CFS immediately postexercise on the SDMT (61 +/- 3 vs 66 +/- 2), SWT (137 +/- 6 vs 146 +/- 6), and SCT (99 +/- 4 vs 107 +/- 3), and 24 hours postexercise on the SDMT (64 +/- 3 vs 69 +/- 2), SWT (134 +/- 7 vs 148 +/- 5), and SCT (101 +/- 4 vs 106 +/- 3). We conclude that after physically demanding exercise, CFS subjects demonstrated impaired cognitive processing compared with healthy individuals.

Randomized, double blind, controlled placebo-phase in trial of low dose phenelzine in the chronic fatigue syndrome

Because of the striking similarity of the clinical manifestations produced by use of the drug reserpine and seen in patients with the chronic fatigue syndrome (CFS), we theorized that CFS was a disorder of reduced central sympathetic drive. Because of the pharmacology of control of this central sympathetic system, we further postulated that CFS symptoms would respond quickly to low dose treatment with a monamine oxidase inhibitor. To test these hypotheses, we designed a randomized, double blind placebo controlled study using phenelzine. No patient in the trial had a diagnosis of lifetime or current psychiatric disorder and none had depressed mood in the range of clinically depressed patients on a paper and pencil test of depression. Patients in the placebo group received placebo for 6 weeks while those in the drug treatment group were treated in three 2-week segments-placebo, 15 mg phenelzine every other day, and then 15 mg daily. This treatment regimen produced a significant pattern of improvement compared to worsening in 20 self report vehicles of CFS symptoms, illness severity, mood or functional status. Thus the data support our hypothesis of reduced sympathetic drive, although an alternative hypothesis of pain alleviation is also possible. The study design also allowed us to evaluate patients for a placebo effect: no evidence for this was found, suggesting that CFS is not an illness due to patients' being overly suggestible.

Chronic paroxysmal hemicrania and hemicrania continua. Interval between indomethacin administration and response

The interval between indomethacin dosage and clinical response was assessed in hemicrania continua (n = 12) and chronic paroxysmal hemicrania (n = 11) sufferers. The number of trials per patient ranged from 1 to 30. At the time of testing, the patients had "considerable" pain after discontinuation of the drug. The dosage used was the usual one for that patient at the given pain level; ie, 25 or 50 mg tid. All the patients had a complete, long-term response to treatment. Nevertheless, the average interval between drug intake and pain relief during the present study ranged between 30 minutes and 48 hours in both disorders. In most patients (10 in both groups), the indomethacin effect was complete within 24 hours, and frequently within 8 hours. It is suggested that interindividual differences in dosage and timing to abolish the headaches may be due to different bioavailability or individual sensitivity. Recommendations on indomethacin testing in unilateral headaches are given.

SUNCT syndrome: repetitive and overlapping attacks

A 79-year-old patient had been suffering from right orbital pain attacks since he was 77. The pain, of an "electrical" or burning character, was moderate to severe in intensity. Single attacks lasted for 30-60 seconds each and were accompanied by prominent ipsilateral conjunctival injection and tearing as well as slight rhinorrhoea. The temporal pattern of attacks was irregular with spontaneous remissions alternating with unpredictable symptomatic phases. During active periods, attacks could be triggered by several precipitants acting on trigeminal and extra-trigeminal innervated areas. On most occasions, the patient had 2-3 attacks daily but, at worst, he might have almost continuous short-lasting attacks in periods of 1 to 3 hours length. When attacks had such frequency they presented either as repetitive or overlapping single episodes. According to the clinical features it is concluded that the case reported is a new case of SUNCT syndrome.

Chronic paroxysmal hemicrania coexisting with migraine. Differential response to pharmacological treatment

A 30 year old woman, suffering from migraine for 14 years, started having chronic paroxysmal hemicrania (CPH) attacks at the age of 29. Both types of headache coexisted for a year without any apparent influence of one type on the other. Treatment with indomethacin had a dramatic effect on the CPH attacks but did not modify the course of the migraine. The independent clinical courses and the differential response to indomethacin are consistent with the knowledge that both types of headache are different and that there is no relationship between them. Owing to the high prevalence of migraine it is likely that some CPH sufferers may have a familial or personal history of migraine; therefore the conjunction of CPH and migraine occurs by chance.

[The multiple sleep latency test in the diagnosis of narcolepsy and idiopathic hypersomnia]

The diagnostic differential between narcolepsy and idiopathic hypersomnia may be difficult in those cases which clinically manifest only hypersomnia and the nocturnal polygraphic study does not show any differences between both diseases, particularly when the beginning of REM sleep is not presented in narcoleptic patients. The multiple sleep latency test is an objective test of daytime hypersomnia in both diseases. Moreover, if 2 or more REM periods are registered altogether in the 4 or 5 siestas studied, the test is highly suggestive of narcolepsy and permits sure differentiation with idiopathic hypersomnia. In the present study, the multiple sleep latency test permitted the diagnosis of the cases of oligosymptomatic narcolepsy and absence of the beginning of REM sleep.

Hemicrania continua. The first Spanish case: a case report

The case of a patient suffering from strictly unilateral continuous headache, absolutely responsive to indomethacin is reported. This is the first Hemicrania continua case to be documented in Spain. The tyramine test resulted in anisocoria with the smaller pupil on the symptomatic side. A second tyramine test after one week on 75 mg indomethacin per day failed to produce anisocoria. Treatment was reduced to 25 mg indomethacin per day, and this dose was sufficient to control the headache completely.

"Hemicrania episodica"--a new type of headache or a pre-chronic stage of hemicrania continua?

For seventeen years, a young man suffered from headaches of one to three days duration occurring once every six or seven days and totally disappearing between episodes. These were strictly unilateral (always on the left side), and were absolutely responsive to indomethacin. They differ clinically from the other two indomethacin-responsive headaches described up to now: Hemicrania Continua (HC) and Chronic Paroxysmal Hemicrania (CPH). He has a sister suffering from HC. Similar to HC, but unlike CPH, topical tyramine in our patient's eyes resulted in anisocoria before, but not after, indomethacin treatment. Our case differs from HC, however, in its time pattern; it could either be a pre-chronic stage of HC or a new type of headache. It seems unlikely that a time pattern that has remained unchanged for 17 years will become continuous, as in HC, in the future, and thus it is possible that our patient represents a case of a new type of headache that we propose to name "Hemicrania Episodica." In any case, it seems probable that this type of headache, although clinically different, may share a common pathogenic basis with HC.