Purkinje cell size is reduced in cerebellum of patients with autism

1. The authors' goal was to compare the size and density of Purkinje cells in the cerebellum of subjects with and without autism. Blocks of cerebellum were dissected at autopsy from the brains of age, sex- and postmortem-intervaled (PMI) groups of autistic and normal control individuals (N = 5 per group). Frozen, unfixed blocks were sectioned and stained with 1% cresyl violet.2. The linear, molecular, granular densities and cross-sectional area of Purkinje cells were measured using computer-assisted image analysis. The average cross-sectional areas of Purkinje cells of the patients with autism were smaller by 24% when compared to the normal subjects. Two of the five autistic subjects had mean Purkinje cell sizes that corresponded to greater than 50% reduction in size. There was a substantial effect size difference in Purkinje cell size (² = 0.29) between control and autistic brains (F(1, 8) = 3.32, P = 0.106). No differences in Purkinje cell densities were observed between the two groups.3. These data indicate the possibility of Purkinje cell atrophy in autism with significant neurohistological heterogeneity among individuals diagnosed with this disorder.     

Suppression of cerebral hemodynamics is associated with reduced functional capacity in patients with heart failure

This investigation elucidated the underlying mechanisms of functional impairments in patients with heart failure (HF) by simultaneously comparing cardiac-cerebral-muscle hemodynamic and ventilatory responses to exercise among HF patients with various functional capacities. One hundred one patients with HF [New York Heart Association HF functional class II (HF-II, n = 53) and functional class III (HF-III, n = 48) patients] and 71 normal subjects [older control (O-C, n = 39) and younger control (Y-C, n = 32) adults] performed an incremental exercise test using a bicycle ergometer. A recently developed noninvasive bioreactance device was adopted to measure cardiac hemodynamics, and near-infrared spectroscopy was employed to assess perfusions in the frontal cerebral lobe (Δ[THb](FC)) and vastus lateralis muscle (Δ[THb](VL)). The results demonstrated that the Y-C group had higher levels of cardiac output, Δ[THb](FC), and Δ[THb](VL) during exercise than the O-C group. Moreover, these cardiac/peripheral hemodynamic responses to exercise in HF-III group were smaller than those in both HF-II and O-C groups. Although the change of cardiac output caused by exercise was normalized, the amounts of blood distributed to frontal cerebral lobe and vastus lateralis muscle in the HF-III group significantly declined during exercise. The HF-III patients had lower oxygen-uptake efficiency slopes (OUES) and greater Ve-Vo(2) slopes than the HF-II patients and age-matched controls. However, neither hemodynamic nor ventilatory response to exercise differed significantly between the HF-II and O-C groups. Cardiac output, Δ[THb](FC), and Δ[THb](VL) during exercise were directly related to the OUES and Vo(2peak) and inversely related to the Ve-Vco(2) slope. Moreover, cardiac output or Δ[THb](FC) was an effect modifier, which modulated the correlation status between Δ[THb](VL) and Ve-Vco(2) slope. We concluded that the suppression of cerebral/muscle hemodynamics during exercise is associated with ventilatory abnormality, which reduces functional capacity in patients with HF.     

Ischemia-induced structural change in SR Ca2+-ATPase is associated with reduced enzyme activity in rat muscle

In this study, we employed an in vivo model of prolonged ischemia in rat skeletal muscle to investigate the hypothesis that structural modifications to the sarcoplasmic reticulum (SR) Ca2+-ATPase can explain the alterations in Ca2+-ATPase activity that occur with ischemia. To induce total ischemia, a tourniquet was placed around the upper hindlimb in 27 female Sprague-Dawley rats weighing 256 +/- 6.7 g (mean +/- SE) and was inflated to 350 mmHg for 4 h. The contralateral limb served as control (C) to the ischemic limb (I), and the limbs of animals killed immediately after anesthetization served as a double control (CC). Mixed gastrocnemius and tibialis anterior muscles were sampled and used for SR vesicle preparation. Maximal Ca2+-ATPase activity (micromol x g protein(-1) x min(-1)) of C (15,802 +/- 1,246) and I (11,609 +/- 1,029) was 90 and 73% (P < 0.05) of CC (17,562 +/- 1,682), respectively. No differences were found between groups in either the Hill coefficient or the free Ca2+ at half-maximal activity. The fluorescent probes, FITC and N-cyclohexyl-N'-(dimethylamino-alpha-naphthyl) carbodiimide, used to assess structural alterations in the regions of the ATP binding site and the Ca2+ binding sites of the Ca2+-ATPase, respectively, indicated a 26% reduction (P < 0.05) in FITC binding capacity (absolute units) in I (0.22 +/- 0.01) compared with CC (0.29 +/- 0.02) and C (0.29 +/- 0.03). Our results suggest that the reduction in maximal SR Ca2+-ATPase activity in SR vesicles with ischemia is related to structural modification in the region of the nucleotide binding domain by mechanisms that are as yet unclear.     

Tinnitus severity is reduced with reduction of depressive mood--a prospective population study in Sweden

Tinnitus, the perception of sound without external source, is a highly prevalent public health problem with about 8% of the population having frequently occurring tinnitus, and about 1-2% experiencing significant distress from it. Population studies, as well as studies on self-selected samples, have reported poor psychological well-being in individuals with tinnitus. However, no study has examined the long-term co-variation between mood and tinnitus prevalence or tinnitus severity. In this study, the relationship between depression and tinnitus prevalence and severity over a 2-year period was examined in a representative sample of the general Swedish working population. Results show that a decrease in depression is associated with a decrease in tinnitus prevalence, and even more markedly with tinnitus severity. Hearing loss was a more potent predictor than depression for tinnitus prevalence, but was a weaker predictor than depression for tinnitus severity. In addition, there were sex differences for tinnitus prevalence, but not for tinnitus severity. This study shows a direct and long-term association between tinnitus severity and depression.     

Degradation of myocardial structural proteins in myocardial infarcted dogs is reduced by Ep459, a cysteine proteinase inhibitor

The purpose of this study is to clarify whether cysteine proteinases play an important role in the degradation of myocardial proteins in the infarcted tissue. We studied the effects of a cysteine proteinase inhibitor, Ep459, on degradation of cardiac structural proteins caused by ischemia due to coronary artery ligation for 24 h. Proteolytic effects of purified cysteine proteinases on isolated cardiac tissue were also examined. Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, degradation of cardiac structural proteins, particularly of myosin heavy chain, alpha-actinin and troponin-I was observed in the infarcted tissue. Treatment with Ep459 significantly reduced protein degradation and total activity of cathepsins B and L in the infarcted tissue, compared with the findings in the untreated group. The electrophoretic pattern of the infarcted myocardium was similar to that of myofibrillar proteins degraded by cathepsins B and L. These results suggest that cysteine proteinases, particularly cathepsins B and L, are involved in degradation of myofibrillar proteins in myocardial infarction.     

New insights into Alzheimer's disease progression: a combined TMS and structural MRI study

Background:

Combination of structural and functional data of the human brain can provide detailed information of neurodegenerative diseases and the influence of the disease on various local cortical areas.

Methodology and Principal Findings:

To examine the relationship between structure and function of the brain the cortical thickness based on structural magnetic resonance images and motor cortex excitability assessed with transcranial magnetic stimulation were correlated in Alzheimer''s disease (AD) and mild cognitive impairment (MCI) patients as well as in age-matched healthy controls. Motor cortex excitability correlated negatively with cortical thickness on the sensorimotor cortex, the precuneus and the cuneus but the strength of the correlation varied between the study groups. On the sensorimotor cortex the correlation was significant only in MCI subjects. On the precuneus and cuneus the correlation was significant both in AD and MCI subjects. In healthy controls the motor cortex excitability did not correlate with the cortical thickness.

Conclusions:

In healthy subjects the motor cortex excitability is not dependent on the cortical thickness, whereas in neurodegenerative diseases the cortical thinning is related to weaker cortical excitability, especially on the precuneus and cuneus. However, in AD subjects there seems to be a protective mechanism of hyperexcitability on the sensorimotor cortex counteracting the prominent loss of cortical volume since the motor cortex excitability did not correlate with the cortical thickness. Such protective mechanism was not found on the precuneus or cuneus nor in the MCI subjects. Therefore, our results indicate that the progression of the disease proceeds with different dynamics in the structure and function of neuronal circuits from normal conditions via MCI to AD.     

The presence of immunoglobulins in the gastric juice of patients infected with Helicobacter pylori is related to a reduced secretion of acid

Background. It has been reported that treatment with proton pump inhibitors (PPI) leads to partial elimination and suppression of Helicobacter pylori. In theory, since acid is known to denature immunoglobulins, this antibacterial activity of PPI may be due to a reduction in the acid output favouring humoral immunity. Materials and methods. We analysed prospectively fasting gastric juice in 54 consecutive patients attending upper endoscopy for pH and levels of IgG, IgA and IgM. In addition, two antral and two corpus biopsies were obtained and histologically examined for the presence of H. pylori. Results. 41/54 patients were infected with H. pylori. Immunoglobulines in the gastric juice of these patients were found in 25/41 (IgG), 27/41 (IgA), and 29/41 (IgM) patients. There was a highly significant difference in the gastric pH when H. pylori infected patients with measurable IgG, IgA, or IgM were compared with those in whom no immunoglobulines were found (median pH: 6 vs. 2 in each group; p < .001) Conclusions. There is a close correlation between a high gastric pH and the presence of IgG, IgA, and IgM antibodies. Hence, it may be speculated that the efficacy of humoral immunity following H. pylori infection depends on a high pH such as resulting from PPI treatment.     

Stabilization of alpha-chymotrypsin upon PEGylation correlates with reduced structural dynamics

Protein stability remains one of the main factors limiting the realization of the full potential of protein therapeutics. Poly(ethylene glycol) (PEG) conjugation to proteins has evolved into an important tool to overcome instability issues associated with proteins. The observed increase in thermodynamic stability of several proteins upon PEGylation has been hypothesized to arise from reduced protein structural dynamics, although experimental evidence for this hypothesis is currently missing. To test this hypothesis, the model protein alpha-chymotrypsin (alpha-CT) was covalently modified with PEGs with molecular weights (M(W)) of 700, 2,000 and 5,000 and the degree of modification was systematically varied. The procedure did not cause significant tertiary structure changes. Thermodynamic unfolding experiments revealed that PEGylation increased the thermal transition temperature (T(m)) of alpha-CT by up to 6 degrees C and the free energy of unfolding [DeltaG(U) (25 degrees C)] by up to 5 kcal/mol. The increase in stability was found to be independent of the PEG M(W) and it leveled off after an average of four PEG molecules were bound to alpha-CT. Fourier-transformed infrared (FTIR) H/D exchange experiments were conducted to characterize the conformational dynamics of the PEG-conjugates. It was found that the magnitude of thermodynamic stabilization correlates with a reduction in protein structural dynamics and was independent of the PEG M(W). Thus, the initial hypothesis proved positive. Similar to the thermodynamic stabilization of proteins by covalent modification with glycans, PEG thermodynamically stabilizes alpha-CT by reducing protein structural dynamics. These results provide guidance for the future development of stable protein formulations.     

Yohimbine-induced amygdala activation in pathological gamblers: a pilot study

Rationale and Objectives

There is evidence that drug addiction is associated with increased physiological and psychological responses to stress. In this pilot functional magnetic resonance imaging (fMRI) study we assessed whether a prototype behavioral addiction, pathological gambling (PG), is likewise associated with an enhanced response to stress.

Methods

We induced stress by injecting yohimbine (0.2–0.3 mg/kg, IV), an alpha-2 adrenoceptor antagonist that elicits stress-like physiological and psychological effects in humans and in laboratory animals, to four subjects with PG and to five non-gamblers mentally healthy control subjects. Their fMRI brain responses were assessed along with subjective stress and gambling urges ratings.

Results

Voxelwise analyses of data sets from individual subjects, utilizing generalized linear model approach, revealed significant left amygdala activation in response to yohimbine across all PG subjects. This amygdala effect was not observed in the five control individuals. Yohimbine elicited subjective stress ratings in both groups with greater (albeit not statically significantly) average response in the PG subjects. On the other hand, yohimbine did not induce urges to gamble.

Conclusions

The present data support the hypothesis of brain sensitization to pharmacologically-induced stress in PG.     

Impaired cytotrophoblast cell-cell fusion is associated with reduced Syncytin and increased apoptosis in patients with placental dysfunction

Preeclampsia (PE), Hemolysis Elevated Liver Enzymes and Low Platelets (HELLP)-syndrome, and intrauterine growth restriction (IUGR) are associated with abnormal placentation. In early pregnancy, placental cytotrophoblasts fuse and form multinuclear syncytiotrophoblasts. The envelope gene of the human endogenous retrovirus-W, Syncytin, is a key factor for mediating cell-cell fusion of cytotrophoblasts. This study investigated clinical parameters of PE and HELLP-associated IUGR and analyzed the cell-cell fusion index and beta-human chorionic gonadotropin (beta-hCG) secretion of cytotrophoblasts isolated and cultured from placentas of these patients. In addition, we performed absolute quantitation of Syncytin and determined the apoptosis rate in both cultured cytotrophoblasts and placental tissues. Cultured cytotrophoblasts from PE and HELLP-associated IUGR correlated with a pronounced lower cell-cell fusion index, 1.8- and 3.6-fold; less nuclei per syncytiotrophoblast, 1.4- and 2.0-fold; a significantly decreased beta-hCG secretion, 4.3- and 17.2-fold and a reduction of Syncytin gene expression, 8.1 (P = 0.019) and 222.7-fold (P = 0.011) compared with controls, respectively. In contrast, a significantly 2.3-fold higher apoptosis rate was observed in cultured PE/IUGR cytotrophoblasts (P = 0.043). Importantly, Syncytin gene expression in primary placental tissues of PE/IUGR was 5.4-fold lower (P = 0.047) and in HELLP/IUGR 10.6-fold lower (P = 0.019) along with a 1.8- and 1.9-fold significant increase in the apoptosis rate compared with controls, respectively. Low Syncytin expression in both cultured cytotrophoblasts and primary tissues from pathological placentas supports an intrinsic placenta-specific deregulation of cell-cell fusion in the formation of syncytiotrophoblasts leading to increased apoptosis. These processes could contribute to the development and severity of PE and HELLP-associated IUGR.     

Electromagnetic field of mobile phones affects visual event related potential in patients with narcolepsy

The effects of the mobile phone (MP) electromagnetic fields on electroencephalography (EEG) and event-related potentials (ERP) were examined. With regard to the reported effects of MP on sleep, 22 patients with narcolepsy-cataplexy were exposed or sham exposed for 45 min to the MP (900 MHz, specific absorption rate 0.06 W/kg) placed close to the right ear in a double blind study. There were no changes of the EEG recorded after the MP exposure. A subgroup of 17 patients was studied on visual ERP recorded during the MP exposure. Using an adapted "odd-ball" paradigm, each patient was instructed to strike a key whenever rare target stimuli were presented. There were three variants of target stimuli (horizontal stripes in (i) left, (ii) right hemifields or (iii) whole field of the screen). The exposure enhanced the positivity of the ERP endogenous complex solely in response to target stimuli in the right hemifield of the screen (P < 0.01). The reaction time was shortened by 20 ms in response to all target stimuli (P < 0.05). In conclusion, the electromagnetic field of MP may suppress the excessive sleepiness and improve performance while solving a monotonous cognitive task requiring sustained attention and vigilance.     

Disease-modifying antirheumatic drugs are associated with a reduced risk for cardiovascular disease in patients with rheumatoid arthritis: a case control study

Rheumatoid arthritis (RA) is characterized by inflammation and an increased risk for cardiovascular disease (CVD). This study investigates possible associations between CVD and the use of conventional disease-modifying antirheumatic drugs (DMARDs) in RA. Using a case control design, 613 RA patients (5,649 patient-years) were studied, 72 with CVD and 541 without CVD. Data on RA, CVD and drug treatment were evaluated from time of RA diagnosis up to the first cardiovascular event or the end of the follow-up period. The dataset was categorized according to DMARD use: sulfasalazine (SSZ), hydroxychloroquine (HCQ) or methotrexate (MTX). Odds ratios (ORs) for CVD, corrected for age, gender, smoking and RA duration, were calculated per DMARD group. Patients who never used SSZ, HCQ or MTX were used as a reference group. MTX treatment was associated with a significant CVD risk reduction, with ORs (95% CI): 'MTX only', 0.16 (0.04 to 0.66); 'MTX and SSZ ever', 0.20 (0.08 to 0.51); and 'MTX, SSZ and HCQ ever', 0.20 (0.08 to 0.54). The risk reductions remained significant after additional correction for the presence of rheumatoid factor and erosions. After correction for hypertension, diabetes and hypercholesterolemia, 'MTX or SSZ ever' and 'MTX, SSZ and HCQ ever' showed significant CVD risk reduction. Rheumatoid factor positivity and erosions both increased CVD risk, with ORs of 2.04 (1.02 to 4.07) and 2.36 (0.92 to 6.08), respectively. MTX and, to a lesser extent, SSZ were associated with significantly lower CVD risk compared to RA patients who never used SSZ, HCQ or MTX. We hypothesize that DMARD use, in particular MTX use, results in powerful suppression of inflammation, thereby reducing the development of atherosclerosis and subsequently clinically overt CVD.     

ER stress is associated with reduced ABCA-1 protein levels in macrophages treated with advanced glycated albumin - reversal by a chemical chaperone

ATP-binding cassette transporter A1 mediates the export of excess cholesterol from macrophages, contributing to the prevention of atherosclerosis. Advanced glycated albumin (AGE-alb) is prevalent in diabetes mellitus and is associated with the development of atherosclerosis. Independently of changes in ABCA-1 mRNA levels, AGE-alb induces oxidative stress and reduces ABCA-1 protein levels, which leads to macrophage lipid accumulation. These metabolic conditions are known to elicit endoplasmic reticulum (ER) stress. We sought to determine if AGE-alb induces ER stress and unfolded protein response (UPR) in macrophages and how disturbances to the ER could affect ABCA-1 content and cholesterol efflux in macrophages. AGE-alb induced a time-dependent increase in ER stress and UPR markers. ABCA-1 content and cellular cholesterol efflux were reduced by 33% and 47%, respectively, in macrophages treated with AGE-alb, and both were restored by treatment with 4-phenyl butyric acid (a chemical chaperone that alleviates ER stress), but not MG132 (a proteasome inhibitor). Tunicamycin, a classical ER stress inductor, also impaired ABCA-1 expression and cholesterol efflux (showing a decrease of 61% and 82%, respectively), confirming the deleterious effect of ER stress in macrophage cholesterol accumulation. Glycoxidation induces macrophage ER stress, which relates to the reduction in ABCA-1 and in reverse cholesterol transport, endorsing the adverse effect of macrophage ER stress in atherosclerosis. Thus, chemical chaperones that alleviate ER stress may represent a useful tool for the prevention and treatment of atherosclerosis in diabetes.     

Acetylcholinesterase enzyme localization in the amygdala: a comparative histochemical and ultrastructural study

The distribution of acetylcholinesterase enzyme was studied in the amygdala of some rodents, subprimates and several primates. The cytoarchitecture of the amygdala has presented various problems to anatomists, including the question as to how many nuclear groups and subgroups should be identified. Among the mammals examined, the arrangement of the amygdaloid nuclei is remarkably uniform and no clear phylogenetic trend can be recognised. Although there are minor differences, there seems to be a general similarity between most mammals examined in so far as the distribution of cholinesterase is concerned. The staining is less intense in the brains of the monkeys examined. The sole exception to the rule, that cholinesterase distribution is slightly different from nucleus to nucleus in different animals, is the magnocellular part of the basal nucleus. This amygdaloid nucleus stains quite strongly in all animals examined. From these findings, and those of others studying the distribution of choline acetyltransferase, it was concluded that the basal amygdaloid nucleus is cholinergic and possible cholinoceptive. The ultrastructural investigations appear to confirm this point. This is particularly applicable to the magnocellular part of the basal amygdaloid nucleus.     

Experimental study of the efficiency of a reduced index in Tribolium

The relative efficiency of a reduced index (IR) relative to a full index (IF) was compared in an experiment with Tribolium. The selection objective included pupal length, adult weight, and egg mass. The reduced index was based on pupal length and adult weight, whereas the full index was based on these traits and also on egg mass. There were five generations of selection with four replicates, and a selected proportion of 20%. For each replicate, an unselected control was produced. Responses were significant in the IF and IR lines. Responses for the selection objective differed significantly between lines (p < 0.01). The efficiency of the IR line relative to the IF line was 0.52, similar to the expected efficiency of 0.51. The IF and IR lines did not differ significantly for pupal length nor adult weight, whereas the response for egg mass in the IF line was significantly different from the response in the IR line. Realized heritability was greater in the IF line (0.63 ± 0.05) than in the IR line (0.37 ± 0.16). The deleted trait (egg mass) has high heritability and genetic and phenotypic correlations nearly equal to zero with the other two traits included in the selection criterion. The results show the importance of including index traits with high genetic value that are independent of other traits, and they could be useful in breeding programs simultaneously considering production and reproduction traits with nearly zero correlations between them.     

Altered neuropathic pain behaviour in a rat model of depression is associated with changes in inflammatory gene expression in the amygdala

The association between chronic pain and depression is widely recognized, the comorbidity of which leads to a heavier disease burden, increased disability and poor treatment response. This study examined nociceptive responding to mechanical and thermal stimuli prior to and following L5‐L6 spinal nerve ligation (SNL), a model of neuropathic pain, in the olfactory bulbectomized (OB) rat model of depression. Associated changes in the expression of genes encoding for markers of glial activation and cytokines were subsequently examined in the amygdala, a key brain region for the modulation of emotion and pain. The OB rats exhibited mechanical and cold allodynia, but not heat hyperalgesia, when compared with sham‐operated counterparts. Spinal nerve ligation induced characteristic mechanical and cold allodynia in the ipsilateral hindpaw of both sham and OB rats. The OB rats exhibited a reduced latency and number of responses to an innocuous cold stimulus following SNL, an effect positively correlated with interleukin (IL)‐6 and IL‐10 mRNA expression in the amygdala, respectively. Spinal nerve ligation reduced IL‐6 and increased IL‐10 expression in the amygdala of sham rats. The expression of CD11b (cluster of differentiation molecule 11b) and GFAP (glial fibrillary acidic protein), indicative of microglial and astrocyte activation, and IL‐1β in the amygdala was enhanced in OB animals when compared with sham counterparts, an effect not observed following SNL. This study shows that neuropathic pain‐related responding to an innocuous cold stimulus is altered in an animal model of depression, effects accompanied by changes in the expression of neuroinflammatory genes in the amygdala .     

Hydrolysis of coagulation factors by circulating IgG is associated with a reduced risk for chronic allograft nephropathy in renal transplanted patients

Chronic allograft nephropathy (CAN), a major cause of late allograft failure, is characterized by a progressive decline in graft function correlated with tissue destruction. Uncontrolled activation of the coagulation cascade by the stressed endothelium of the graft is thought to play an important role in the pathophysiology of CAN. In this study, we demonstrate that circulating IgG from renal-transplanted patients are endowed with hydrolytic properties toward coagulation factors VIII and IX, but fail to hydrolyze factor VII and prothrombin. The hydrolytic activity of IgG was reliably quantified by the measure of the hydrolysis of a fluorescent synthetic substrate for serine proteases: proline-phenylalanine-arginine-methylcoumarinamide (PFR-MCA). A retrospective case-control study indicated that an elevated hydrolysis rate of PFR-MCA by circulating IgG correlated with the absence of CAN lesions on protocol graft biopsy performed 2 years posttransplantation. We propose that circulating hydrolytic IgG may counterbalance the procoagulation state conferred by the activated endothelium by disrupting the amplification loop of thrombin generation which is dependent on factors VIII and IX. Interestingly, low rates of PFR-MCA hydrolysis, measured 3 mo posttransplantation, were predictive of CAN at 2 years down the lane. These data suggest that PFR-MCA hydrolysis may be used as a prognosis marker for CAN in renal-transplanted patients.