Effects of lipopolysaccharide on the radiation-induced changes in the blood-brain barrier and the astrocytes

The use of radiation to improve the efficacy of chemotherapy on malignant brain tumors is also known to cause side effects on vascular endothelial cells and astrocytes in normal parts of the brain. We investigated the effects of lipopolysaccharide (LPS) on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during whole-brain irradiation in rats. The permeability of the BBB to Evans blue (EB) dye significantly increased in the cerebral cortex, diencephalon and cerebellum regions of rats exposed to irradiation (P<0.01). In contrast, the BBB permeability in irradiated rats was significantly reduced by LPS (P<0.05). Tumor necrosis factor-alpha (TNF-alpha) levels were increased following LPS, irradiation and irradiation plus LPS (P<0.05, P<0.01). Irradiated brain vessels showed a considerable loss of staining intensity of tight junction proteins Zonula occludens-1 (ZO-1) and occludin. Staining for Zonula occludens-1 and occludin was intensive in animals treated with LPS and irradiation plus LPS. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in very few astrocytes of irradiated brains. However, this staining showed an increased positive intensity in the brain sections of LPS-treated as well as of irradiation plus LPS-treated animals. These results indicate that LPS reduces the passage of exogenous vascular tracer EB-binding albumin into the brain, at least partly, by increasing the expression of tight junction proteins and GFAP, following the irradiation. We suggest that irradiation may affect paracellular permeability through disruption of tight junction proteins, Zonula occludens-1 and occludin, and LPS could provide beneficial effects on the BBB integrity and the astrocytes against irradiation damage.     

Distribution of symptoms of conduct disorder and antisocial personality disorder in Turkey

BACKGROUND: A variety of conduct disorder (CD) symptoms are seen together as a symptom cluster. Among CD symptoms there are serious and stubborn antisocial behaviors: lying, swindling, running away from home/school, destructiveness, arson, kidnapping women, sexual abuse, and armed robbery. The objective of this study was to discover the relationship between CD and antisocial personality disorder (APD) and the distribution of the symptoms of these disorders. SAMPLING AND METHODS: The research sample consisted of 994 individuals between the ages of 18 and 65 years in Sivas province. Subjects were given the Diagnostic Interview Schedule-III-R (DIS-III-R) APD subscale. RESULTS: The lifetime prevalence for CD and APD was found to be 21.03 and 3.02%, respectively. In both disorders the percentage of men was higher than for women. The comorbidity of both disorders was found to be 14.35%. The most frequently seen CD symptom in normal society is 'lying', but in those with CD 'initiates a fight several times' is the most frequently seen symptom. In those with APD the most frequently seen symptom is 'truant from school several times'. CONCLUSIONS: Identifying risk factors in children could be an important step in preventing the progression of CD and APD.     

Doppler measurement of blood flow velocities in extraocular orbital vessels in patients with obstructive sleep apnea syndrome

PURPOSE: We used color Doppler sonography to determine blood flow velocities in the extraocular orbital vessels of patients with obstructive sleep apnea syndrome (OSAS) and compared the results with those of healthy control subjects without OSAS. METHODS: Patients with OSAS were classified according to the apnea-hypopnea index (AHI) as having mild OSAS (AHI < 20) or severe OSAS (AHI > or = 20). The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index were measured in the ophthalmic artery (OA), central retinal artery (CRA), lateral short posterior ciliary artery, and medial short posterior ciliary artery using color Doppler sonography. Only 1 eye was measured in each study participant, and right and left eyes were chosen randomly. The blood flow velocities of patients with OSAS and those of control subjects were compared with the Kruskal-Wallis test and Wilcoxon's rank-sum test. RESULTS: The study comprised 30 patients (15 with mild and 15 with severe OSAS) and 20 healthy control subjects. Blood flow velocities were higher in most measured vessels in patients with OSAS than they were in the control subjects. Among patients with mild OSAS, the PSVs and EDVs in the posterior ciliary arteries were statistically significantly higher than those of the control group (p < 0.05), but those in the OA and CRA did not differ significantly between the mild OSAS group and the control group (p > 0.05). However, as the severity of OSAS increased, the PSVs and EDVs of the OA and CRA were also affected (p < 0.05). CONCLUSIONS: Color Doppler sonographic measurements of blood flow parameters in the orbital vessels may differ significantly between patients with OSAS and those without the syndrome. Therefore, OSAS should be considered in addition to other conditions when interpreting the results of color Doppler sonography of the extraocular orbital vessels if the clinical history points toward such a diagnosis.     

Shigatoxin-1 binding and receptor expression in human kidneys do not change with age

Postdiarrheal hemolytic-uremic syndrome (D+HUS) occurs predominantly in young children. The rarity of D+HUS in adults has been ascribed to aging-associated loss of glomerular globotriaosylceramide (Gb3) expression, the major cognate receptor for shigatoxin. This belief, however, is based on relatively little data. The current study was undertaken to examine renal shigatoxin-1 (Stx-1) binding and Gb3 expression by human kidneys from varying aged subjects. Immunofluorescent staining and thin layer chromatography of neutral lipid extracts were performed. Abundant Stx-1 binding to both glomeruli and tubules was observed in frozen renal sections from all subjects of all ages (6 months to 85 years). The pattern of Stx-1 binding was identical between adults and children, with glomerular endothelial cells and cortical tubules being strongly labeled. Stx-1 binding affinity was similar between pediatric and adult kidneys. Antibodies to Gb3 showed a similar pattern and degree of staining regardless of donor age. In addition, Gb3 levels in glomeruli and tubules isolated from fresh kidney tissue were comparable between different aged donors. These data demonstrate that intrinsic renal binding of Stx-1 does not vary with age. It is suggested that factors other than basal renal Gb3 expression account for the age-related incidence of acute renal failure in D+HUS.     

mtDNA nt3243 Mutation, External Ophthalmoplegia, and Hypogonadism in an Adolescent Girl

A 14-year-old girl presented with a 3-month history of easy fatigue and exercise intolerance, especially when climbing stairs. She had a mild ptosis and mild limitation of upward gaze. Her puberty was delayed, and she manifested hypogonadotrophic hypogonadism. Serum lactic and pyruvic acids were elevated. Cranial magnetic resonance imaging was normal. Muscle biopsy documented typical ragged-red fibers. A point mutation at nucleotide 3243 in the tRNA^Leu(UUR) (typical mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) mutation) was detected in mitochondrial DNA from both blood and muscle tissues, indicating that our patient was suffering from a mitochondrial myopathy. Hypogonadism may be a manifestation of the MELAS nucleotide 3243 mutation.     

In vitro evaluation of dentin permeability of fluorotic primary teeth with a new electronic hydraulic conductance measurement system with photosensors

OBJECTIVES: The permeability characteristics of dentin have been used in many in vitro studies to evaluate longitudinally the efficacy of various restorative and preventative procedures. The easiest way to evaluate dentin permeability is to calculate its hydraulic conductance (Lp) by fluid filtration method. There are researches on electronic hydraulic conductance measurement systems which can give more precise and reliable results of permeability of dentine than the classical system. To the authors' knowledge, there are no studies on bonding properties of restoratives to fluorotic primary teeth and dentin permeability of those teeth in the literature. The aim of this in vitro study was to determine the dentin permeability of fluorotic primary molars precisely with a new 'electronic hydraulic conductance measurement system with photosensors' and to compare the data with healthy primary molars. METHODS: A total of 40 fluorotic and healthy primary second molar teeth with 1/3 root resorption, which were extracted for orthodontic purpose and with no caries, restoration, fracture or crack were selected and used in this study. Teeth were classified according to the modified form of dental fluorosis index of Thylstrup&Fejerskov. Dentin discs were placed in the electronic hydraulic conductance measurement system with photosensors which was designed for the measurement of dentin permeability. The amount of distilled water passed through each dentin disk (muL/min) under a constant pressure was determined. Dentin permeability data of the fluorotic and healthy teeth were recorded and analysed statistically. RESULTS: It was observed that dentin permeability decreases, while dental fluorosis severity increases in primary teeth.     

Clinical investigation: thyroid function test abnormalities in cardiac arrest associated with acute coronary syndrome

Introduction

It is known that thyroid homeostasis is altered during the acute phase of cardiac arrest. However, it is not clear under what conditions, how and for how long these alterations occur. In the present study we examined thyroid function tests (TFTs) in the acute phase of cardiac arrest caused by acute coronary syndrome (ACS) and at the end of the first 2 months after the event.

Method

Fifty patients with cardiac arrest induced by ACS and 31 patients with acute myocardial infarction (AMI) who did not require cardioversion or cardiopulmonary resuscitation were enrolled in the study, as were 40 healthy volunteers. The patients were divided into three groups based on duration of cardiac arrest (<5 min, 5–10 min and >10 min). Blood samples were collected for thyroid-stimulating hormone (TSH), tri-iodothyronine (T₃), free T₃, thyroxine (T₄), free T₄, troponin-I and creatine kinase-MB measurements. The blood samples for TFTs were taken at 72 hours and at 2 months after the acute event in the cardiac arrest and AMI groups, but only once in the control group.

Results

The T₃ and free T₃ levels at 72 hours in the cardiac arrest group were significantly lower than in both the AMI and control groups (P < 0.0001). On the other hand, there were no significant differences between T₄, free T₄ and TSH levels between the three groups (P > 0.05). At the 2-month evaluation, a dramatic improvement was observed in T₃ and free T₃ levels in the cardiac arrest group (P < 0.0001). In those patients whose cardiac arrest duration was in excess of 10 min, levels of T₃, free T₃, T₄ and TSH were significantly lower than those in patients whose cardiac arrest duration was under 5 min (P < 0.001, P < 0.001, P < 0.005 and P < 0.05, respectively).

Conclusion

TFTs are significantly altered in cardiac arrest induced by ACS. Changes in TFTs are even more pronounced in patients with longer periods of resuscitation. The changes in the surviving patients were characterized by euthyroid sick syndrome, and this improved by 2 months in those patients who did not progress into a vegetative state.