The role of microRNA in neuronal inflammation and survival in the post ischemic brain: a review

Each year, more than 790 000 people in the United States suffer from a stroke. Although progress has been made in diagnosis and treatment of ischemic stroke (IS), new therapeutic interventions to protect the brain during an ischemic insult is highly needed. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression post-transcriptionally. Growing evidence suggests that miRNAs have a profound impact on ischemic stroke progression and are potential targets of novel treatments. Notably, inflammatory pathways play an important role in the pathogenesis of ischemic stroke and its pathophysiologic progression. Experimental and clinical studies have illustrated that inflammatory molecular events collaboratively contribute to neuronal and glial cell survival, edema formation and regression, and vascular integrity. In the present review, we examine recent discoveries regarding miRNAs and their roles in post-ischemic stroke neuropathogenesis.

Lithium chloride ameliorated spatial cognitive impairment through activating mTOR phosphorylation and inhibiting excessive autophagy in the repeated cerebral ischemia-reperfusion mouse model

Lithium has been previously demonstrated to alleviate cognitive impairment caused by neurodegenerative diseases and acute brain injuries; however, the specific mechanism remains elusive. In the present study, the C57BL/6 mouse model of spatial cognitive impairment induced by repeated cerebral ischemia-reperfusion was established. Morris water maze test was performed to evaluate the levels of spatial cognitive impairment. Nissl staining was used to observe any morphological alterations, whilst western blotting was performed to measure the expression levels of microtubule-associated protein light chain 3 (LC3) and Beclin1 in addition to mTOR phosphorylation. LiCl was found to significantly improve spatial learning and memory impairments according to data from the Morris water maze test. Nissl staining indicated that LiCl inhibited neuronal damage in the CA1 region of the hippocampus. Additionally, LiCl increased mTOR phosphorylation, reduced beclin1 expression and reduced the LC3 II/I expression ratio. Taken together, these findings suggest that LiCl may alleviate the spatial cognitive impairment induced by repeated cerebral ischemia-reperfusion. This observation may be attributed to the inhibition of excessive autophagy by LiCl through mTOR signaling activation.

Surgical treatment of malignant paraganglioma with spinal invasion in a juvenile patient: A case report

RATIONALE

Paragangliomas are rare neuroendocrine tumors that originate in specialized cells derived from the neural crest with metastasis to the thoracic spine being among the rarest forms. Here, we are presenting a detailed analysis of a case of malignant paraganglioma in the thoracic spinal region in a 14-year-old boy. Our focus is to emphasize the importance of considering malignant paraganglioma as a diagnosis and guiding the perioperative management upon surgical treatment. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 14-year-old boy presented with a 5-month history of continuous and progressive elevated blood pressure and back pain. The patient, who had been diagnosed of malignant paraganglioma in the left posterior mediastinum for 3 months, received surgical resection of paraganglioma in the left posterior mediastinum, which had involved the left intervertebral foramen of T4. However, the tumor was not completely resected during the first operation.

DIAGNOSES

Magnetic resonance imaging of spine and positron emission tomography-computed tomography showed spinal cord compression secondary to the epidural component of the T4 mass, with increased marrow infiltration of the left T4 intervertebral foramen, which was difficult to be removed. Postoperative pathology confirmed the diagnosis of spinal involvement of malignant paraganglioma.

INTERVENTIONS

The patient underwent biopsy and percutaneous vertebroplasty of T4 and paravertebral lesions, and needle-track cement augmentation via a posterior approach.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 10-month follow-up visit. There were no other complications associated with the operation during the follow-up period.

LESSONS

Combined efforts of specialists from orthopedics, neurosurgery, thoracic surgery, and medical oncology led to the successful diagnosis and management of this patient. Malignant paraganglioma of thoracic spine, although rare, should be part of the differential diagnosis when the patient has a history of paraganglioma and presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the malignant paraganglioma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment. However, we need to take the potential risk of complications in bone cement applications into full consideration.

Surgical management of spinal metastases of thymic carcinoma: A case report and literature review

RATIONALE

Metastatic thymic carcinoma in the spine is a rare disease with no standard curative managements yet. The objective of this study is to report a very rare case of spinal metastases of thymic carcinoma successfully operated by combination of instrumentation and cement augmentation together with adjuvant treatment. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 57-year-old man presented with a 6-month history of continuous and progressive back pain. The patient, who had been diagnosed of thymic carcinoma (stage IV B) for 3 years, received surgical treatment of median sternotomy thymectomy, followed by 3 cycles of chemotherapy and 12 cycles of radiotherapy.

DIAGNOSIS

Magnetic resonance imaging (MRI) of spine showed spinal cord compression secondary to the epidural component of the T4 mass, with increased metastatic marrow infiltration of the left T4 vetebral body, which presented as a solid tumor. Post-operative pathology confirmed the diagnosis of spinal metastases of thymic carcinoma.

INTERVENTIONS

The patient underwent exploratory surgery, circumferential spinal cord decompression, cement augmentation and a stabilization procedure via a posterior approach.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 3-month follow-up visit. There were no other complications associated with the operation during the follow-up period.

LESSONS

Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Combined efforts of specialists from orthopedics, neurosurgery, thoracic surgery, and medical oncology led to the successful diagnosis and management of this patient. Metastatic thymic carcinoma of the spine, although rare, should be part of the differential diagnosis when the patient has a history of thymic carcinoma and presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the metastatic thymic carcinoma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment.

Successful treatment of malignant thymoma with sacrum metastases: A case report and review of literature

RATIONALE

Malignant thymoma in the spine is a rare disease without standard curative managements so far. The objective of this article is to report a very rare case of recurrent malignant thymoma with sacrum metastases causing severe lumbosacral pain, which was presented with acute radiculopathy and treated with 2 operations combined with stabilization and cement augmentation. The management of these unique cases is not well-documented.

PATIENT CONCERNS

A 75-year-old man presented with lumbosacral pain, radiating pain and numbness of the left extremity. The patient underwent thymectomy in 2008, and posterior spinal cord decompression, tumor resection and a stabilization procedure in 2011. Pathologic results confirmed malignant thymomas of the spine. Imaging studies revealed the density of soft tissues, obvious bony destruction in the sacrum, and significant spinal cord obstruction.

DIAGNOSES

We believe this is a less-documented case of metastatic thymoma of the sacral spine presenting with back pain and radiculopathy, and presenting as a giant solid tumor.

INTERVENTIONS

The patient underwent osteoplasty via a posterior approach. Pathologic results confirmed malignant thymomas of the sacral spine.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 6-month and 1-year follow-up visit. There were no other complications associated with the operation during the follow-up period.

LESSONS

This article emphasizes metastatic thymoma of the spine, although rare, should be part of the differential when the patient presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the metastatic thymoma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment.

Successful treatment of malignant pheochromocytoma with sacrum metastases: A case report

RATIONALE

Malignant pheochromocytoma in the spine is a rare disease without standard curative managements so far. The objective of this article is to report a very rare case of malignant pheochromocytoma with sacrum metastases causing severe lumbosacral pain, which was presented with acute radiculopathy and treated with three operations combined with cement augmentation and stabilization. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 58-year-old man presented with lumbosacral pain, radiating pain and numbness of the right extremity. The patient underwent excision of right adrenal pheochromocytoma in 2010. Imaging studies revealed the density of soft tissues, obvious bony destruction in the sacrum, and significant spinal cord obstruction.

DIAGNOSES

We believe this is the first report of malignant pheochromocytoma with sacrum metastases.

INTERVENTIONS

The patient underwent tissue biopsy and osteoplasty after embolization of the internal iliac artery in January 2015, and exploratory surgery, circumferential spinal cord decompression, and a stabilization procedure via a posterior approach in June 2015 due to spinal canal stenosis caused by cement. Since the position of pedicle screw was not good enough, a revision surgery was performed the next day following the procedures in June 2015.

OUTCOMES

The patient's neurological deficits improved significantly after the third surgery, and the postoperative period was uneventful at the three-year follow-up visit.

LESSONS

We recommend the posterior approach for spinal decompression of the metastatic pheochromocytoma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment. However, the potential risk of complications in bone cement applications need to be fully recognized.

Malignant pheochromocytoma with multiple vertebral metastases causing acute incomplete paralysis during pregnancy: Literature review with one case report

RATIONALE

We present a rare case of malignant pheochromocytoma with thoracic metastases during pregnancy that presented with symptoms of myelopathy and was treated with circumferential decompression, stabilization, and radiation. The management of this unique case is not well documented. The clinical manifestations, imaging results, pathological characteristics, treatment and prognosis of the case were analyzed.

PATIENT CONCERNS

A 26-year-old pregnant woman with a history of paroxysmal hypertension during the second trimester presented with lower extremity weakness, numbness, urinary incontinence, and back pain. Imaging studies revealed a right adrenal pheochromocytoma, multiple metastases at T8, T11, T12, and the pelvis girdle causing significant multilevel cord compression and significant osteolytic lesions at T11 and T12.

DIAGNOSES

We believe this is the first reported case of metastatic pheochromocytoma of the thoracic spine presenting with symptoms of myelopathy during pregnancy.

INTERVENTIONS

A healthy neonate was delivered by emergency caesarean section at 34 weeks. Subsequently, the patient underwent a circumferential spinal cord decompression and a stabilization procedure.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 6-month follow-up visit.

LESSONS

This article emphasizes that metastatic pheochromocytoma of the spine, although rare, should be part of the differential when a patient presents with elevated blood pressure, weakness, and urinary incontinence.

Factors Associated with Benign Paroxysmal Positional Vertigo: A Chinese Case-Control Study

Background

Benign paroxysmal positional vertigo (BPPV) is one of the most common and most successfully treated vestibular disorders. However, there is a lack of predictive factors for BPPV in clinical practice. We aimed to explore several possible predictive factors for BPPV in the Chinese population.

Material/Methods

We enrolled 240 patients with BPPV from Beijing Chaoyang Hospital between July 2013 and July 2016. Biochemical and hematological markers were obtained along with the history of cardiovascular and cerebrovascular diseases.

Results

Serum uric acid (SUA) [279.0±84.7 vs. 331.0±82.7], hemoglobin A1C (HbA1c) [5.75±1.17 vs. 6.61±1.00], albumin [38.1±3.71 vs. 40.9±4.1], and creatinine [68.4±19.3 vs. 81.5±24.1] were significantly lower in patients with BPPV compared with controls (P<0.05). Multiple logistic regression analysis showed that lower levels of HbA1c and albumin were independently associated with BPPV (P<0.05), with odds ratio (OR) 0.680 (95% CI 0.551–0.839) and 0.338 (95% CI 0.190–0.603), respectively. However, the level of SUA was not independently related with BPPV [OR=0.999 (95% CI 0.991–1.006), P=0.713]. There were no significant differences between the parameters of systolic blood pressure, diastolic blood pressure, blood routine examination, lipid profiles, homocysteine, pre-albumin, and blood urea nitrogen in patients with BPPV vs. controls (P>0.05).

Conclusions

Lower levels of HbA1c and albumin were independently associated with BPPV. Although the level of SUA was lower in BPPV patients, SUA was not an independent risk factor for BPPV.

Motor Imagery-Based Rehabilitation: Potential Neural Correlates and Clinical Application for Functional Recovery of Motor Deficits after Stroke

Motor imagery (MI), defined as the mental implementation of an action in the absence of movement or muscle activation, is a rehabilitation technique that offers a means to replace or restore lost motor function in stroke patients when used in conjunction with conventional physiotherapy procedures. This article briefly reviews the concepts and neural correlates of MI in order to promote improved understanding, as well as to enhance the clinical utility of MI-based rehabilitation regimens. We specifically highlight the role of the cerebellum and basal ganglia, premotor, supplementary motor, and prefrontal areas, primary motor cortex, and parietal cortex. Additionally, we examine the recent literature related to MI and its potential as a therapeutic technique in both upper and lower limb stroke rehabilitation.

Validation of the Essen Stroke Risk Score in different subtypes of ischemic stroke

OBJECTIVE

Predictive scores are important tools for stratifying patients based on their risk of future vascular events and for selecting preventive therapies. The aim of this study is to validate the Essen Stroke Risk Score (ESRS) for stratifying stroke recurrence in different subtypes of non-atrial fibrillation ischemic stroke in a large Chinese cohort.

METHODS

Data were derived from the Blood pressure and clinical Outcome in Stroke Survivors registry, which includes a cohort of 2204 stroke patients. All patients were further classified according to the TOAST (Trial of Org 10 172 in Acute Stroke Treatment) criteria. We stratified one-year cumulative rates for stroke and composite vascular events using the ESRS. The predictive power of the ESRS was assessed using the area under the receiver-operator curves (AUC).

RESULTS

Among 1699 patients included in the study, the AUC of ESRS was 0.58 (95% CI: 0.52-0.64) for recurrent stroke, whereas 0.59 (95% CI: 0.53-0.64) for composite vascular events at 1 year. In patients with large-artery atherosclerosis (LAA) subtype of stroke, the AUC of ESRS was both 0.61 (95% CI: 0.54-0.68) for recurrent stroke and composite vascular events. However, no significant AUC was observed in patients with small-artery occlusion subtype of stroke.

CONCLUSIONS

In patients with LAA subtype of non-atrial fibrillation stroke, the ESRS has moderate accuracy in stratifying the risk of both recurrent strokes and major vascular events within the first year. However, the ESRS couldn't accurately stratify the risk of recurrent strokes in patients with small-artery atherosclerosis subtype of non-atrial fibrillation stroke.

The cerebral circulation and cerebrovascular disease III: Stroke

In this paper, our review series on cerebrovascular disease anatomy, physiology, and pathology ends with a thorough discussion of the most significant cerebrovascular pathology: stroke. This discussion proceeds through two layers of organization. First, stroke is divided up into its main etiologic categories (ischemic stroke/transient ischemic attack, hemorrhagic stroke, and ischemic to hemorrhagic transformation). Then, the epidemiological, pathophysiological, clinical, and therapeutic (employed currently as well as emerging) aspects of each etiology are explored; emphasis is placed upon the therapeutic aspects. Finally, once we have covered all aspects of each etiologic category, we end our review with a defense of the thesis that there is much hope for the future of stroke treatment to be derived from familiarity with the literature on emerging therapies.

The cerebral circulation and cerebrovascular disease II: Pathogenesis of cerebrovascular disease

In this paper, we review the cerebral circulation and cerebrovascular disease (CVD) with an overview of the major types of CVD pathogenesis. These, as categorized here, are as follows: occlusive injury intrinsic to blood vessels, occlusive injury extrinsic to blood vessels, cerebral hypoperfusion, and cerebral hemorrhage. Following an overview of each of these categories, we conclude with a discussion of cerebral edema to illustrate how the pathological origins we covered can progress clinically. The content of this paper sets the stage for the detailed, clinically oriented discussion of stroke with which our series culminates in its subsequent Part III.

The cerebral circulation and cerebrovascular disease I: Anatomy

In this paper, which is the first in a three-part series that reviews cerebrovascular anatomy, pathogenesis, and stroke, we lay the anatomical foundation for the rest of the series. Beginning with its origin in the branches of the aorta, we start by describing the arterial system. This system is partitioned into two major divisions (anterior and posterior circulations) that differ significantly in features and pathogenic potential. The systems, and the major branches that comprise them, are described. Description of the arterial system proceeds to the point of the fulfillment of its function. This function, the exchange of gases and nutrients with the cerebral parenchyma, is the subject of a subsequent section on the microcirculation and blood-brain barrier. Finally, the cerebral venous system, which is composed of cerebral veins and dural venous sinuses, is described. Thus, an anatomical context is supplied for the discussion of cerebrovascular disease pathogenesis provided by our second paper.

Abstract T P245: Decreased Metallopeptidase and Aquaporin Expressions by Acute Ethanol Administration: A Potential Treatment for Ischemic Stroke?

Introduction: Cerebral ischemia up-regulation of aquaporin (AQP) and metallopeptidase (MMP) expressions is related to increasing blood-brain barrier (BBB) permeability and brain edema. Ethanol (EtOH) has been shown to provide neuroprotective effects. The precise mechanisms by which these effects occur have yet to be elucidated. In this study, we tested the relationship of the neuroprotective effects of EtOH post-stroke with MMP2, MMP9 and AQP4, AQP9 expressions utilizing both in vitro and in vivo models.

Methods: A total of 72 adult male Sprague-Dawley rats were subjected to 2h right middle cerebral artery (MCAO). Different doses of EtOH (0.5 g/kg and 1.5 g/kg) were administered by intraperitoneal injection 2h after stroke. Brain edema estimates were obtained by measuring brain water content. BBB permeability was measured by Evans blue dye assay. Oxygen-glucose deprivation and re-oxygenation (OGD) experiments were performed on whole brain slice cultures. Western-blots were performed to measure protein levels of AQP4, AQP9, MMP9, MMP2, tight junction protein (ZO-1) and basal lamina.

Results: The EtOH treatment dose dependently reduced infarct volume (MCAo: 53.92%±0.03%; EtOH 0.5 g/kg: 50.04%±0.02%;1.5 g/kg: 28.41%±0.02%) compared to the control group. The 1.5 g/kg EtOH treatment significantly decreased lesion volume, BBB leakage (Stroke: 46.8±4.5 ug/g; 1.5 g/kg: 33.5±3.8 ug/g) and brain edema (Stroke: 83.2%±0.3%; 1.5 g/kg: 80.6%±0.8%) compared to the stroke saline-treated group. The EtOH (1.5 g/kg) treatment also significantly reduced the levels of AQP9, AQP4, MMP2 and MMP9 compared to the stroke control group, while no significant difference was observed between the two ethanol treatment groups. Furthermore, in vitro results show reductions in MMP and AQP expressions, induced by EtOH treatment, are associated with elevated ZO-1 and basal lamina levels.

Conclusion: EtOH is an effective neuroprotective therapy identified by the reduction in infarct volume, edema volume, and BBB leakage after stroke. Decreases in MMP2, MMP9, AQP4, and AQP9 expressions may contribute to EtOH-induced neuroprotection.

Factors associated with delayed intracerebral hemorrhage after superficial temporal artery-middle cerebral artery bypass in steno-occlusive cerebrovascular diseases

BACKGROUND

Intra-cerebral hemorrhage (ICH) is a devastating complication that can result from superficial temporal artery-middle cerebral artery (STA-MCA) bypass in patients undergoing treatment for steno-occlusive cerebrovascular disease (CVD). There is a clinical need to find the possible risk factors to prevent ICH, as it is a significant cause of mortality and morbidity. The aim of the study was to investigate the factors associated with delayed ICH after STA-MCA bypass in patients with steno-occlusive CVDs.

METHODS

We retrospectively analyzed the records of 163 patients seen from 2002 to 2011 with STA-MCA bypass for steno-occlusive cerebrovascular diseases at the Department of Neurosurgery, Xuan Wu Hospital, Beijing. Demographic and clinical data, including age, gender, vascular risk factors, preoperative syndrome, preoperative National Institutes of Health Stroke Scale (NIHSS), ipsilateral ischemic lesions, classification of steno-occlusive CVDs, donor branches of STA, graft patency, postoperative hypertension, and postoperative-increased MCA velocity were recorded and analyzed. Binary Logistic regression served to identify factors associated with delayed ICH after STA-MCA bypass.

RESULTS

We identified 8 (4.9%) patients with delayed ICH after STA-MCA bypass. Patients with hypertension, preoperative stroke, ipsilateral ischemic lesions, postoperative hypertension and postoperative-increased MCA velocity were significantly more prone to experiencing delayed ICH after STA-MCA bypass. Logistic regression analysis shows ipsilateral ischemic lesions, postoperative hypertension, and postoperative-increased MCA velocity remained independent predictors for delayed ICH after STA-MCA bypass.

CONCLUSION

Despite the varied associated factors in patients with steno-occlusive CVDs, ipsilateral ischemic lesions, postoperative hypertension, and postoperative-increased MCA velocity could be associated with delayed ICH after STAMCA bypass.

Reduced apoptosis by combining normobaric oxygenation with ethanol in transient ischemic stroke

BACKGROUND AND PURPOSE

The effect of normobaric oxygen (NBO) on apoptosis remains controversial. The present study evaluated the effect of NBO on ischemia-induced apoptosis and assessed the potential for improved outcomes by combining NBO administration with another neuroprotective agent, ethanol, in a rat stroke model.

METHODS

Rats were subjected to right middle cerebral artery occlusion (MCAO) for 2h. At the onset of reperfusion, ischemic animals received either NBO (2h duration), an intraperitoneal injection of ethanol (1.0g/kg), or both NBO and ethanol. Extent of brain injury was determined by infarct volume, neurological deficit, and apoptotic cell death. Expression of pro- and anti-apoptotic proteins was evaluated through Western immunoblotting.

RESULTS

Given alone, NBO and ethanol each slightly (p<0.05) reduced infarct volume to 38% and 37%, respectively, as compared to the impressive reduction of 51% (p<0.01) seen with combined NBO-ethanol administration. Neurologic deficits were also significantly reduced by 48% with combined NBO-ethanol therapy, as compared to lesser reductions of 24% and 23% with NBO or ethanol, respectively. Combined NBO-ethanol therapy decreased apoptotic cell death by 49%, as compared to 31% with NBO and 30% with ethanol. Similarly, combination therapy significantly increased expression of anti-apoptotic factors (Bcl-2 and Bcl-xL) and significantly reduced expression of pro-apoptotic proteins (BAX, Caspase-3, and AIF), as compared to the minimal or nil protein expression changes elicited by NBO or ethanol alone.

CONCLUSIONS

In rats subjected to ischemic stroke, NBO administration salvages ischemic brain tissue through evidenced decrease in apoptotic cell death. Combined NBO therapy with ethanol administration greatly improves both degree of neuroprotection and associated apoptosis.

Hyperglycemia in stroke and possible treatments

Hyperglycemia affects approximately one-third of acute ischemic stroke patients and is associated with poor clinical outcomes. In experimental and clinical stroke studies, hyperglycemia has been shown to be detrimental to the penumbral tissue for several reasons. First, hyperglycemia exacerbates both calcium imbalance and the accumulation of reactive oxygen species (ROS) in neurons, leading to increased apoptosis. Second, hyperglycemia fuels anaerobic energy production, causing lactic acidosis, which further stresses neurons in the penumbral regions. Third, hyperglycemia decreases blood perfusion after ischemic stroke by lowering the availability of nitric oxide (NO), which is a crucial mediator of vasodilation. Lastly, hyperglycemia intensifies the inflammatory response after stroke, causing edema, and hemorrhage through disruption of the blood brain barrier and degradation of white matter, which leads to a worsening of functional outcomes. Many neuroprotective treatments addressing hyperglycemia in stroke have been implemented in the past decade. Early clinical use of insulin provided mixed results due to insufficiently controlled glucose levels and heterogeneity of patient population. Recently, however, the latest Stroke Hyperglycemia Insulin Network Effort trial has addressed the shortcomings of insulin therapy. While glucagon-like protein-1 administration, hyperbaric oxygen preconditioning, and ethanol therapy appear promising, these treatments remain in their infancy and more research is needed to better understand the mechanisms underlying hyperglycemia-induced injuries. Elucidation of these mechanistic pathways could lead to the development of rational treatments that reduce hyperglycemia-associated injuries and improve functional outcomes for ischemic stroke patients.

At low doses ethanol maintains blood-brain barrier (BBB) integrity after hypoxia and reoxygenation: a brain slice study

Post-ischemia ethanol (EtOH) treatments have been shown to exhibit neuroprotective effects in stroke. However, the mechanisms underlying these effects and those on blood-brain barrier (BBB) integrity have yet to be elucidated. In the present study, we determined whether administering differing concentrations of EtOH alter the expressions of BBB integral proteins, including aquaporins-4 and -9 (AQP-4, AQP-9), matrix metallopeptidases-2 and -9 (MMP-2, MMP-9), zonula occludens-1 (ZO-1), and basal lamina (laminin). We employed an organotypic brain slice culture model that utilizes oxygen-glucose deprivation followed by reoxygenation (OGD/R). Brain slices were obtained from 10-day-old Sprague-Dawley rats and divided into the following five groups (n = 8 subjects per group): (1) control, (2) hypoxia (OGD/R), no EtOH, (3) OGD/R and 10 mM EtOH, (4) OGD/R and 30 mM EtOH, and (5) OGD/R and 90 mM EtOH. To assess BBB integrity, levels of AQPs, MMPs, ZO-1, and laminin were determined by Western blot. Compared to control, OGD/R without EtOH significantly increased AQP-4, AQP-9, MMP-2, and MMP-9 levels, while decreasing ZO-1 and laminin levels. All EtOH concentration treatments (groups 3 through 5) significantly reduced the expressions of AQP-4, AQP-9, MMP-2, and MMP-9, compared to the OGD/R, non-alcohol treated slices. Furthermore, compared to the OGD/R without EtOH group, the 30 mM EtOH treatment significantly increased ZO-1 and laminin levels. In contrast, the 90 mM EtOH level neither enhanced the reduction in AQP and MMP levels nor increased ZO-1 or basal lamina expressions observed in the 30 mM treatment. In conclusion, at an optimal dose of 30 mM, EtOH improves the expressions of MMP-2, MMP-9, AQP-4, AQP-9, ZO-1, and basal laminin, previously altered by OGD/R. These effects may indicate a beneficial effect of EtOH on BBB integrity after stroke.

Minocycline for acne vulgaris: efficacy and safety

BACKGROUND

Minocycline is a tetracycline antibiotic that is commonly used in the treatment of moderate to severe acne vulgaris. Although it is more convenient for patients to take than first-generation tetracyclines, as it only needs to be taken once or twice a day and can be taken with food, it is more expensive. Concerns have also been expressed over its safety following the deaths of two patients taking the drug. There is a lack of consensus among dermatologists over the relative risks and benefits of minocycline. As most acne prescribing is undertaken by general practitioners, it is important that guidelines issued to them are based on the best available evidence rather than personal judgements.

OBJECTIVES

To collate and evaluate the evidence on the clinical efficacy of minocycline in the treatment of inflammatory acne vulgaris. Specific objectives were to compare the efficacy of minocycline with other drug treatments for acne and to collate information on the incidence of adverse drug reactions.

SEARCH STRATEGY

Randomised controlled trials (RCTs) of minocycline for acne vulgaris were identified by searching the following electronic databases; MEDLINE, EMBASE, Biosis, Biological Abstracts, International Pharmaceutical Abstracts, Cochrane Skin Group's Trial Register, Theses Online, BIDS ISI Science Citation Index, National Research Register, Current Controlled Trials and Bids Index to Scientific and Technical Proceedings. Other strategies used were scanning the references of articles retrieved, hand-searching of major dermatology journals and personal communication with trialists and drug companies.

SELECTION CRITERIA

To be eligible for the review, studies had to be RCTs comparing the efficacy of minocycline at any dose to active or placebo control, in subjects with inflammatory acne vulgaris. Diagnoses of papulo-pustular, polymorphic and nodular acne were also accepted. Trials were not excluded on the basis of language.

DATA COLLECTION AND ANALYSIS

27 randomised controlled trials met the inclusion criteria and were included in this review. The comparators used were placebo (2 studies), oxytetracycline (1), tetracycline (6), doxycycline (7), lymecycline (2), topical clindamycin (3), topical erythromycin/zinc (1), cyproterone acetate/ ethinyloestradiol (1), oral isotretinoin (2), topical fusidic acid (1) and there was one dose response study. Two studies are ongoing and it remains to be clarified whether one further study is a RCT. Major outcome measures used in the trials included lesion counts, acne grades/severity scores, doctors' and patients' global assessments, adverse drug reactions and drop out rates. The quality of each study was assessed independently by two assessors and an effect size calculated where possible. An additional three RCTs and three safety studies were identified by searches conducted in November 2002; these will be reviewed for a major update in early 2003 when it is anticipated that the results of the two ongoing studies will be available.

MAIN RESULTS

The trials were generally small and of poor quality and in many cases the published reports were inadequate for our purpose. Pooling of the studies was not attempted due to the lack of common outcome measures and endpoints and the unavailability of some primary data. Although minocycline was shown to be an effective treatment for acne vulgaris, in only two studies was it found to be superior to other tetracyclines. Both of these were conducted under open conditions and had serious methodological problems. A third study showed it to be more effective than 2% fusidic acid, applied topically, against inflammatory lesions in mild to moderate acne. Differences in the way adverse drug reactions were identified could have accounted for the wide variation between studies in numbers of events reported. This meant that no overall evaluation could be made of incidence rates of adverse events associated with minocycline therapy. No RCT evidence was found to support the benefits of minocycline in acne resistant to other therapies and the dose response has only been evaluated up to eight weeks of therapy.

REVIEWER'S CONCLUSIONS

Minocycline is likely to be an effective treatment for moderate acne vulgaris, but this review found no reliable RCT evidence to justify its continued use first-line, especially given the price differential and the concerns that still remain about its safety. Its efficacy relative to other acne therapies could not be reliably determined due to the poor methodological quality of the trials and lack of consistent choice of outcome measures. Similarly the relative risk of adverse drug reactions could not be ascertained reliably and no recommendations can be made concerning the appropriate dose that should be used. It is hoped that this review will highlight the inadequacy of acne trials in general and encourage improvements in methodological quality and standards of reporting.

[The method of removing methamidophos from contaminated vegetables]

Since the massive food poisoning outbreak in 1987, imported vegetables contaminated with methamidophos continued to cause sporadic food poisoning outbreaks in Hong Kong. Despite various administrative measures to lower the risk of importing vegetables, it is evident that the occurrence of sporadic food poisoning outbreaks cannot be completely stemmed out. The education of the public on the effective ways to remove methamidophos from the contaminated vegetables was reckoned to the another preventive measure against food poisoning. A study was carried out to evaluate the effectiveness of various ways of treating the vegetables before consumption. In this study, the removal of methamidophos by simply washing with water at near room temperature was found to be a slow process. The concentration of methamidophos was reduced by about 65% after washing in water for an hour. Further washing did not improve the situation. The addition of detergents and various washing aids including potassium permanganate, hydrogen peroxide, sodium bicarbonate and vinegar did not greatly enhance the removal effectiveness. Among the various treatment procedures, soaking in hot water was the most effective way to remove methamidophos from vegetables. Less than 10% of the pesticide remained in the vegetables after soaking in boiling water for 1 minute.