Effects of chronic immobilization stress on anxiety-like behavior and basolateral amygdala morphology in Fmr1 knockout mice

Several lines of clinical evidence support the idea that fragile X syndrome (FXS) may involve a dysregulation of hypothalamic-pituitary-adrenal axis function [Wisbeck et al. (2000) J Dev Behav Pediatr 21:278-282; Hessl et al. (2002) Psychoneuroendocrinology 27:855-872]. We had tested this idea in a mouse model of FXS (Fmr1 KO) and found that the hormonal response to acute stress was similar to that of wild-type (WT) mice [Qin and Smith (2008) Psychoneuroendocrinology 33:883-889]. We report here responses to chronic stress (CS) in Fmr1 KO mice. Following restraint for 120 min/d, 10 consecutive days, we assessed dendrite and spine morphology in basolateral amygdala (BLA). We also monitored behavior in an elevated plus maze (EPM) and the hormonal response to this novel spatial environment. After CS, mice of both genotypes underwent adrenal hypertrophy, but effects were greater in WT mice. Behavior in the EPM indicated that only WT mice had the expected increase in anxiety following CS. Serum corticosterone and adrenocorticotropic hormone (ACTH) levels were both increased following the spatial novelty of EPM, and there were no differences between genotypes in the hormonal responses. BLA dendritic branching increased proximal to the soma in WT, but in Fmr1 KO mice branching was unaffected close to the soma and slightly decreased at one point distal to the soma. Similarly, spine density on apical and basal dendrites increased in WT but decreased in Fmr1 KO mice. Spine length on apical and basal dendrites increased in WT but was unaffected in Fmr1 KO mice. These differences in behavioral response and effects on neuron morphology in BLA suggest a diminished adaptive response of Fmr1 KO mice.

The feasibility of light microscopic measurements of intercellular spaces in squamous epithelium in the lower-esophagus of GERD patients

The study aims to determine whether light microscopy can be used to accurately measure the diameters of intercellular spaces between squamous epithelial cells in the lower esophagus, and whether changes in this outcome measure can be used as a diagnostic marker for gastroesophageal reflux disease (GERD). The study has two parts. Part 1 involves 42 asymptomatic controls and 119 patients with typical symptoms of GERD, including 58 with erosive esophagitis (EE), and 61 patients with nonerosive gastroesophageal reflux disease (NERD). All biopsies were taken from the lower esophagus. All samples were observed using an immersion objective, after which diameters were measured by computer-assisted morphometry. Part 2 involves 61 individuals who were randomly selected from part 1, including 19 controls, 13 with NERD and 29 with EE. Diameter measurements using both light microscopy and transmission electron microscopy (TEM) were performed for samples of 61 individuals. Samples from a total of 61 individuals (31 male, 30 female, mean age 44.3 ± 16.0 years) were observed using both light microscopy and TEM. Both methods showed significant differences between control and disease groups; the outcomes from the two methods had a certain correlation (r = 0.605, P = 0.000). Morphometric analysis of all 161 individuals (83 males, 78 females, mean age 41.4 ± 15.7) showed mean diameters from light microscopy to be 0.58 ± 0.16 µm for controls, 1.07 ± 0.30 µm for NERD, and 1.29 ± 0.20 µm for EE; differences between control and disease groups were significant (P<0.05). The optimal cut-off value from receiver operator characteristic analysis was 0.85 µm. Diagnoses were validated using the combination of symptoms of GERD, endoscopy, and 24 h ambulatory pH monitoring as the gold standard. At the optimal cutoff, sensitivity was 93.3% and specificity was 100%. The diameters of the intercellular spaces in squamous epithelium of lower esophagus from controls and in patients with GERD can be quantitatively measured using light microscopy. Dilated diameters can serve as a sensitive, specific, and objective indicator for diagnosis of GERD.

Remote pharmacological post-conditioning by intrathecal morphine: cardiac protection from spinal opioid receptor activation

BACKGROUND

Intrathecal morphine pre-conditioning attenuates cardiac ischemia-reperfusion injury via activation of central opioid receptors. We hypothesized that intrathecal morphine also post-conditions the myocardium in the rat.

METHODS

Intrathecal morphine at 0.3 μg/kg (LMPC), 3 μg/kg (MMPC) or 30 μg/kg (HMPC) was administered for 5 min before 120-min reperfusion following 30-min ischemia. Infarct size as a percentage of area at risk (IS/AAR) was determined using triphenyltetrazolium staining. MMPC was repeated following the intrathecal administration of nor BNI, NTD, CTOP, or naloxone methiodide (NM), kappa, delta, mu and non-specific opioid receptor antagonists, respectively. The role of peripheral opioid, adenosine and calcitonin gene-related peptide (CGRP) receptors was examined by the intravenous administration of NM, 8-ρ-sulfophenyl theophylline (8-SPT) and human CGRP fragment (CGRP(8-37)), respectively.

RESULTS

Morphine post-conditioning at all three doses was cardioprotective (IS/AAR of LMPC=37 ± 4%, MMPC=35 ± 5%, HMPC=32 ± 4%, control=50 ± 5%, P<0.01). The prior administration of opioid receptor antagonists intrathecally, as well as intravenous 8-SPT and CGRP(8-37) receptor antagonists, abolished this effect (nor BNI+MMPC=47 ± 7%, NTD+MMPC=49 ± 7%, CTOP+MMPC=45 ± 9%, NM+MMPC=47 ± 6% 8-SPT+MPC=46 ± 5% & CGRP(8-37)+MPC=53 ± 6%, P=0.63). However, the intravenous administration of NM did not prevent the protective effect (34 ± 4%, P<0.01).

CONCLUSIONS

Intrathecal morphine administration can induce pharmacological cardiac post-conditioning as it involves opioid receptor centrally but non-opioid receptors peripherally.

Disruption of the SCN2A and SCN3A genes in a patient with mental retardation, neurobehavioral and psychiatric abnormalities, and a history of infantile seizures

Mutations in genes encoding voltage-gated sodium channels are significant factors in the etiology of neurological diseases and psychiatric disorders, including various types of idiopathic epilepsy. Using a clinical exon-targeted oligonucleotide array comparative genomic hybridization (aCGH), we have identified a de novo ~110-kb deletion involving exons 1-2 of SCN2A and non-coding exon 1a of SCN3A in a 25-year-old female with mental retardation, neurobehavioral and psychiatric abnormalities, and a history of infantile seizures with abnormal EEG. We propose that haploinsufficiency of SCN2A may play an important role in the genetic basis of neurodevelopmental and neurobehavioral disorders and emphasize the efficacy of detecting exonic copy-number variation (CNV) by exon-targeted oligo aCGH.

Differences between bisphosphonates in binding affinities for hydroxyapatite

Bisphosphonates (BPs) inhibit bone resorption and are widely used for the treatment of bone diseases, including osteoporosis. BPs are also being studied for their effects on hydroxyapatite (HAP)-containing biomaterials. There is a growing appreciation that there are hitherto unexpected differences among BPs in their mineral binding affinities that affect their pharmacological and biological properties. To study these differences, we have developed a method based on fast performance liquid chromatography using columns of HAP to which BPs and other phosphate-containing compounds can adsorb and be eluted by using phosphate buffer gradients at pH 6.8. The individual compounds emerge as discrete and reproducible peaks for a range of compounds with different affinities. For example, the peak retention times (min; mean +/- SEM) were 22.0 +/- 0.3 for zoledronate, 16.16 +/- 0.44 for risedronate, and 9.0 +/- 0.28 for its phosphonocarboxylate analog, NE10790. These results suggest that there are substantial differences among BPs in their binding to HAP. These differences may be exploited in the development of biomaterials and may also partly explain the extent of their relative skeletal retention and persistence of biological effects observed in both animal and clinical studies.

Catalpol attenuates MPTP induced neuronal degeneration of nigral-striatal dopaminergic pathway in mice through elevating glial cell derived neurotrophic factor in striatum

The protective effect of an iridoid catalpol extracted and purified from the traditional Chinese medicinal herb Rehmannia glutinosa on the neuronal degeneration of nigral-striatal dopaminergic pathway was studied in a chronic 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridine (MPTP)/probenecid C57BL/6 mouse model and in 1-methyl-4-phenylpyridimium (MPP(+)) intoxicated cultured mesencephalic neurons. Rotarod performance revealed that the locomotor ability of mice was significantly impaired after completion of model production and maintained thereafter for at least 4 weeks. Catalpol orally administered for 8 weeks (starting from the second week of model production) dose dependently improved the locomotor ability. HPLC revealed that catalpol significantly elevated striatal dopamine levels without changing the metabolite/dopamine ratios. Nor did it bind to dopamine receptors. Therefore it is unlikely that catalpol resembles any of the known compounds for treating Parkinsonism. Instead, catalpol dose dependently raised the tyrosine hydroxylase (TH) neuron number in substantia nigra pars compacta (SNpc), the striatal dopamine transporter (DAT) density and the striatal glial cell derived neurotrophic factor (GDNF) protein level. Linear regression revealed that both the TH neuron number and DAT density were positively correlated to the GDNF level. In the cultured mesencephalic neurons, MPP(+) decreased the dopaminergic neuron number and shortened the neurite length, whereas catalpol showed protective effect dose dependently. Furthermore, the expression of GDNF mRNA was up-regulated by catalpol to a peak nearly double of normal control in neurons intoxicated with MPP(+) for 24 h but not in normal neurons. The GDNF receptor tyrosine kinase RET inhibitor 4-amino-5-(4-methyphenyl)-7-(t-butyl)-pyrazolo-[3,4-d]pyrimidine (PP1) abolished the protective effect of catalpol either partially (TH positive neuron number) or completely (neurite length). Taken together, catalpol improves locomotor ability by attenuating the neuronal degeneration of nigral-striatal dopaminergic pathway, and this attenuation is at least partially through elevating the striatal GDNF expression.

Multiwall nanotubes can be stronger than single wall nanotubes and implications for nanocomposite design

Molecular dynamics modeling shows that multiwall carbon nanotubes (MWCNTs) with sp;{3} interwall bonding have strengths exceeding those of single-wall carbon nanotubes (SWCNTs) containing the same size initial intrawall defect, and are far less sensitive to defect size. Thus, although processing methods used to increase interwall coupling also create intrawall defects, analyses here show that the strengthening effects and enhanced load transfer compensate for the creation of defects and make MWCNTs with interwall bonding preferable to SWCNTs as mechanical reinforcements in composites. These results are consistent with new experimental data and suggest a new design methodology for CNT-based composites.

Propofol anesthesia does not alter regional rates of cerebral protein synthesis measured with L-[1-(11)C]leucine and PET in healthy male subjects

We report regional rates of cerebral protein synthesis (rCPS) in 10 healthy young males, each studied under two conditions: awake and anesthetized with propofol. We used the quantitative L-[1-(11)C]leucine positron emission tomography (PET) method to measure rCPS. The method accounts for the fraction (lambda) of unlabeled leucine in the precursor pool for protein synthesis that is derived from arterial plasma; the remainder comes from proteolysis of tissue proteins. Across 18 regions and whole brain, mean differences in rCPS between studies ranged from -5% to 5% and were within the variability of rCPS in awake studies (coefficient of variation range: 7% to 14%). Similarly, differences in lambda (range: 1% to 4%) were typically within the variability of lambda (coefficient of variation range: 3% to 6%). Intersubject variances and patterns of regional variation were also similar under both conditions. In propofol-anesthetized subjects, rCPS varied regionally from 0.98+/-0.12 to 2.39+/-0.23 nmol g(-1) min(-1) in the corona radiata and in the cerebellum, respectively. Our data indicate that the values, variances, and patterns of regional variation in rCPS and lambda measured by the L-[1-(11)C]leucine PET method are not significantly altered by anesthesia with propofol.

The viability and proliferation of human chondrocytes following cryopreservation

Human articular cartilage samples were retrieved from the resected material of patients undergoing total knee replacement. Samples underwent automated controlled freezing at various stages of preparation: as intact articular cartilage discs, as minced articular cartilage, and as chondrocytes immediately after enzymatic isolation from fresh articular cartilage. Cell viability was examined using a LIVE/DEAD assay which provided fluorescent staining. Isolated chondrocytes were then cultured and Alamar blue assay was used for estimation of cell proliferation at days zero, four, seven, 14, 21 and 28 after seeding. The mean percentage viabilities of chondrocytes isolated from group A (fresh, intact articular cartilage disc samples), group B (following cryopreservation and then thawing, after initial isolation from articular cartilage), group C (from minced cryopreserved articular cartilage samples), and group D (from cryopreserved intact articular cartilage disc samples) were 74.7% (95% confidence interval (CI) 73.1 to 76.3), 47.0% (95% CI 43 to 51), 32.0% (95% CI 30.3 to 33.7) and 23.3% (95% CI 22.1 to 24.5), respectively. Isolated chondrocytes from all groups were expanded by the following mean proportions after 28 days of culturing: group A ten times, group B 18 times, group C 106 times, and group D 154 times. This experiment demonstrated that it is possible to isolate viable chondrocytes from cryopreserved intact human articular cartilage which can then be successfully cultured.

Regional rates of cerebral protein synthesis measured with L-[1-11C]leucine and PET in conscious, young adult men: normal values, variability, and reproducibility

We report regional rates of cerebral protein synthesis (rCPS) measured with the fully quantitative L-[1-(11)C]leucine positron emission tomography (PET) method. The method accounts for the fraction (lambda) of unlabeled amino acids in the precursor pool for protein synthesis derived from arterial plasma; the remainder (1-lambda) comes from tissue proteolysis. We determined rCPS and lambda in 18 regions and whole brain in 10 healthy men (21 to 24 years). Subjects underwent two 90-min dynamic PET studies with arterial blood sampling at least 2 weeks apart. Rates of cerebral protein synthesis varied regionally and ranged from 0.97+/-0.70 to 2.25+/-0.20 nmol/g per min. Values of rCPS were in good agreement between the two PET studies. Mean differences in rCPS between studies ranged from 9% in cortical regions to 15% in white matter. The lambda value was comparatively more uniform across regions, ranging from 0.63+/-0.03 to 0.79+/-0.02. Mean differences in lambda between studies were 2% to 8%. Intersubject variability in rCPS was on average 6% in cortical areas, 9% in subcortical regions, and 12% in white matter; intersubject variability in lambda was 2% to 8%. Our data indicate that in human subjects low variance and highly reproducible measures of rCPS can be made with the L-[1-(11)C]leucine PET method.

Use of acute hyperphenylalaninemia in rhesus monkeys to examine sensitivity and stability of the L-[1-11C]leucine method for measurement of regional rates of cerebral protein synthesis with PET

We have previously shown by direct comparison with autoradiographic and biochemical measurements that the L-[1-(11)C]leucine positron emission tomography method provides accurate determinations of regional rates of cerebral protein synthesis (rCPS) and the fraction (lambda) of unlabeled leucine in the precursor pool for protein synthesis derived from arterial plasma. In this study, we examine sensitivity of the method to detect changes in lambda and stability of the method to measure rCPS in the face of these changes. We studied four isoflurane-anesthetized monkeys dynamically scanned with the high resolution research tomograph under control and mild hyperphenylalaninemic conditions. Hyperphenylalaninemia was produced by an infusion of phenylalanine that increased plasma phenylalanine concentrations three- to five-fold. In phenylalanine-infused monkeys, plasma leucine concentrations remained relatively constant, but values of lambda were statistically significantly decreased by 11% to 15%; rCPS was unaffected. Effects on lambda are consistent with competitive inhibition of leucine transport by increased plasma phenylalanine. The effect on lambda shows that competition for the transporter results in a reduction in the fraction of leucine in the precursor pool for protein synthesis coming from plasma. Even under these hyperphenylalaninemic conditions, rCPS remains unchanged due to the compensating increased contribution of leucine from protein degradation to the precursor pool.

FK506 in the treatment of children with nephrotic syndrome of different pathological types

OBJECTIVE

To evaluate the efficacy of FK506 in the treatment of children with nephrotic syndrome of different underlying pathology.

METHODS

12 patients were treated with FK506 with a dosage of 0.1 - 0.15 mg/kg/d while corticosteroid dose was tapered stepwise. This therapeutic course lasted 3 - 6 months during which the plasma concentration ofFK506 was monitored.

RESULTS

12 children with different pathological types nephrotic syndrome were treated with FK506, including 4 cases of MCN, 6 cases of MsPGN, and 1 case of MPGN and 1 case of FSGS. After 2-month duration, 8 patients got complete remission including 4 cases of MCN and 4 cases of MsPGN and 3 children including 1 case of MsPGN, 1 case of MPGN, and 1 case of FSGS got partial remission. Only 1 child with MsPGN was considered to be a treatment failure. The overall response rate was 91.67% with the plasma concentration of FK506 maintained at 5 approximately 12 ng/ml, and the response time was 10 - 38 days. After 1-month duration, all patients except one experienced a reduction in proteinuria to normal levels or a partial response (50% reduction in protein excretion), significant increase in serum albumin, decrease in serum cholesterol and triglyceride and disappearance of edema. 2 months later, in 11 patients, blood biochemical values had returned to normal levels. The drug was generally well-tolerated. 3 patients had anorexia, nausea, vomiting. 2 patients experienced transient elevated serum creatinine which was reversible after the adjustment of dosage. 3 patients had minor changes in urine NAG. Only 2 of all patients relapsed.

CONCLUSION

FK506 is one of the effective immunosuppressants. In this study, FK506 in combination with a small doses of steroid while decreasing FK506 dosage plays a role in consolidating the curative effect and preventing relapse. In conclusion, FK506 may be effective in the treatment of nephrotic syndrome.

Transplantation of embryonic stem cell-derived cardiomyocytes improves cardiac function in infarcted rat hearts

BACKGROUND

Post-infarct congestive heart failure is one of the leading causes of morbidity and mortality in industrialized countries. The main purpose of this study was to investigate whether transplantation of embryonic stem cell-derived cardiomyocytes (ESCM) directly into the infarcted myocardium could improve cardiac function in rats.

METHODS

Cell culture medium with or without ESCM was injected into the borders of cardiac scar tissue 1 week after experimental infarction. Cardiac performance was evaluated 4 weeks later by means of echocardiography after ESCM (n=16) or medium (n=12) injection.

RESULTS

ESCM implantation significantly improved fractional shortening (31.5+/-3. 8%) compared with medium-treated hearts (21.3+/-5.2%; P<0.05) and preserved left ventricular structure. Co-localization of 4',6-diamidino-2-phenylindole-labeled nuclei of transplanted cells with cardiomyocyte markers for cardiac troponin T and connexin-43, as detected by immunofluorescent microscopy, indicated the regeneration of damaged myocardium and the formation of gap junctions between grafted and host cells. However, intra-myocardial teratomas were observed in the hearts of two of the 16 grafted animals, at the fourth week after ESCM transplantation.

DISCUSSION

Our results suggest that, although ESCM implantation can improve the function of infarcted myocardium, strategies to prevent tumorigenesis should be developed.

Observation of high-field-side crash and heat transfer during sawtooth oscillation in magnetically confined plasmas

High resolution (temporal and spatial), two-dimensional images of electron temperature fluctuations during sawtooth oscillations were employed to study the crash process and heat transfer in magnetically confined toroidal plasmas. The combination of kink and local pressure driven instabilities leads to a small poloidally localized puncture in the magnetic surface at both the low and the high field sides of the poloidal plane. This observation closely resembles the "fingering event" of the ballooning mode model with the high- mode only predicted at the low field side.

Comparison study of 2D images of temperature fluctuations during sawtooth oscillation with theoretical models

High temporal and spatial resolution two-dimensional (2D) images of electron temperature fluctuations were employed to study the sawtooth oscillation in the Toroidal Experiment for Technically Oriented Research tokamak plasmas. The 2D images are directly compared with the expected 2D patterns of the plasma pressure (or electron temperature) from various theoretical models. The observed experimental 2D images are only partially in agreement with the expected patterns from each model: The image of the initial reconnection process is similar to that of the ballooning mode model. The intermediate and final stages of the reconnection process resemble those of the full reconnection model. The time evolution of the images of the hot spot or island is partially consistent to those from the full reconnection model but is not consistent with those from the quasi-interchange model.