Peroxisomal proliferator-activated receptor gamma co-activator-1 alpha gene expression increases above the lactate threshold in human skeletal muscle

AIM

Peroxisomal proliferator-activated receptor gamma co-activator-1 alpha (PGC-1α) plays a role not only as an activator of mitochondrial biogenesis, but also as a suppressor of inflammatory cytokines, which induce chronic diseases. Therefore, increasing PGC-1α expression can be one of the important factors for preventing chronic diseases. PGC-1α expression is activated by adenosine monophosphate-activated protein kinase (AMPK) and cAMP dependent kinase. The activity of these enzymes depends on the exercise intensity. Therefore, this study compared the effects of two different exercise intensities (above lactate threshold (LT) and below LT) with an equal amount of energy expenditure on PGC-1α gene expression in human skeletal muscle.

METHODS

Six young men participated in this study. They performed exercise at 120% and 80% LT intensity. The duration of the 120% LT exercise was 60 minutes and the duration of the session performed at 80% LT was calculated to yield equal energy expenditure as the 120% LT intensity exercise. Skeletal muscle was obtained after 1 hour of exercise.

RESULTS

The working rate, % peak VO2 and HR during exercise were significantly higher in at 120% LT than at 80% LT. PGC-1α gene expression was not significantly different between control (0.087; 0.026-0.284 (the median; inter quartile range)) and 80% LT (0.171; 0.030-0.484). However, PGC-1α gene expression after 120% LT (0.441; 0.121-4.643) was significantly higher than in the control.

CONCLUSION

The findings of this study suggest that PGC-1α gene expression depends on exercise intensity.

Magnetic resonance characteristics of temporomandibular joint disc displacement in elderly patients

OBJECTIVES

The purpose of this study was to evaluate the MR characteristics of temporomandibular joint (TMJ) disc displacement in elderly patients.

METHODS

Of the MR images of 1660 TMJs in 847 patients with disc displacement who underwent MRI for suspected temporomandibular disorders, 301 TMJs in 154 patients aged over 50 years were studied as an elderly group. These MR images of the elderly group were compared with those of a control group (1359 TMJs in 693 patients aged under 51 years) concerning disc displacement with or without reduction, joint effusion and osteoarthrosis.

RESULTS

The incidence of disc displacement with osteoarthrosis was significantly different between the elderly (41.9%) and the control (19.8%) groups (p = 0.000). Logistic multivariate regression analysis demonstrated that the osteoarthrosis was a significant variable (odds ratio = 2.94, p = 0.000).

CONCLUSIONS

This study suggests that MR characteristics of TMJ disc displacement in elderly patients includes osteoarthrosis.

Changes in chest wall thickness during four-dimensional CT in particle lung treatment planning

Four-dimensional (4D) CT images for charged particle lung therapy were acquired using a 256 multislice CT without couch movement. The thickness of the posterior right chest wall changed with respiration with a water equivalent path length (WEL) of more than 5 mm over the mid-exhalation phase but the thickness of the left chest wall did not vary.

Platelet-derived growth factor regulates breast cancer progression via β-catenin expression

OBJECTIVE

The knowledge on the association between platelet-derived growth factor (PDGF) signaling and epithelial cancers is scarce, although overexpression of PDGF and PDGF receptors has been reported in some human mesenchymal tumors. Thus, we studied the effect of PDGF on breast cancer cells in vitro and the distribution of PDGF in breast cancer tissues.

METHODS

The effect of PDGF-BB on breast cancer cells was assessed by Western blotting, immunofluorescence, WST and 5-bromo-2-deoxyuridine incorporation experiments. PDGF-B and β-catenin expression was investigated in breast cancer tissues by immunohistochemistry.

RESULTS

PDGF-BB induces β-catenin expression in breast cancer cells, and immunohistochemically the distribution of PDGF-B was similar to β-catenin in breast cancer cells. PDGF-B-positive cancer cells were more frequent in cases of ductal carcinoma in situ (87.5%) than invasive carcinoma (61.2%). In addition, PDGF-B staining was stronger in intraductal than invasive cancer cells. PDGF-BB tended to induce nuclear translocation of β-catenin, cell proliferation and DNA incorporation in MDA-MB231 cells, while these results were not found in MCF-7 cells.

CONCLUSION

Our results suggest that PDGF-BB regulates protein expression of β-catenin and is associated with cancer cell behavior.

Overexpression of 14-3-3ζ in cancer cells activates PI3K via binding the p85 regulatory subunit

The ubiquitously expressed 14-3-3 proteins regulate many pathways involved in transformation. Previously, we found that 14-3-3ζ overexpression increased Akt phosphorylation in human mammary epithelial cells. Here, we investigated the clinical relevance and molecular mechanism of 14-3-3ζ overexpression-mediated Akt phosphorylation and the potential impact on breast cancer progression. We found that 14-3-3ζ overexpression was significantly (P = 0.005) associated with increased Akt phosphorylation in human breast tumors. Additionally, 14-3-3ζ overexpression combined with strong Akt phosphorylation was significantly (P=0.01) associated with increased cancer recurrence in patients. In contrast, knockdown of 14-3-3ζ expression by siRNA in cancer cell lines and tumor xenografts reduced Akt phosphorylation. Furthermore, 14-3-3ζ enhanced Akt phosphorylation through activation of PI3K. Mechanistically, 14-3-3ζ bound to the p85 regulatory subunit of PI3K and increased PI3K translocation to the cell membrane. A single 14-3-3 binding motif encompassing serine 83 on p85 is largely responsible for 14-3-3ζ-mediated p85 binding and PI3K/Akt activation. Mutation of serine 83 to alanine on p85 inhibited 14-3-3ζ binding to the p85 subunit of PI3K, reduced PI3K membrane localization and activation, impeded anchorage independent growth and enhanced stress induced apoptosis. These findings revealed a novel mechanism by which 14-3-3ζ overexpression activates PI3K, a key node in the mitogenic signaling network known to promote malignancies in many cell types.

Aberrant expression of disintegrin-metalloprotease proteins in the formation and progression of uterine cervical cancer

OBJECTIVE

Dysregulated expression of disintegrin-metalloprotease proteins [a disintegrin and metalloproteases (ADAMs) and ADAMs with thrombospondin motif (ADAMTSs)] has been reported in many types of cancers and is believed to play an important role in cancer formation and metastasis. However, little is known about the expression of ADAMs and ADAMTSs in the development of human cervical cancer.

METHODS

Reverse transcriptase polymerase chain reaction and immunoblotting were performed to assess the expression of several disintegrin-metalloproteases and tissue inhibitors of metalloproteinases (TIMPs) in squamous-type cervical cancer cells and oncogenically modified keratinocytes (immortalized human cervical keratinocytes transduced with human papilloma virus-16 E6/E7 proteins with or without oncogenes). Immunohistochemistry of ADAM-9, ADAM-10 and TIMP-3 was performed on 31 primary human cervical tissue specimens of preinvasive and invasive cervical carcinoma.

RESULTS

mRNA levels of ADAM-9, ADAM-10, ADAM-12, TIMP-2 and TIMP-3 were upregulated as cervical cells progressed from dysplastic to malignant lesions compared to normal cervical cells. These results were corroborated at the protein level by Western blot analysis and immunohistochemistry.

CONCLUSION

The expression of disintegrin-metalloproteases and their endogenous regulators was dysregulated during cervical carcinogenesis. The aberrant expression of ADAMs might contribute to the pathogenesis of cervical cancer formation and progression.

Effect of HF in LiPF6 Based Electrolytes on the Properties of Surface Passivation Films Formed on Graphite Electrodes in Li Secondary Batteries

The effect of hydrofluoric acid (HF) concentration in conventional LiPF6/EC+DEC electrolyte on the properties of solid electrolyte interphase (SEI) films formed on synthetic graphite electrode and the electrochemical performance were studied using x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), elemental analysis and electrochemical measurement. The morphology and composition of SEI are affected by a small amount of HF in the electrolyte. Higher F content in the SEI was observed when high HF electrolyte were used, although the irreversible capacities used for formation of SEI were nearly the same value. The cycleability of the synthetic graphite electrode was greatly improved when surface film contains larger amount of LiF.

Ciprofloxacin inhibits advanced glycation end products-induced adhesion molecule expression on human monocytes

BACKGROUND AND PURPOSE Advanced glycation end products (AGEs) subtypes, proteins or lipids that become glycated after exposure to sugars, can induce complications in diabetes. Among the various AGE subtypes, glyceraldehyde-derived AGE (AGE-2) and glycolaldehyde-derived AGE (AGE-3) are involved in inflammation in diabetic patients; monocytes are activated by these AGEs. Ciprofloxacin (CIP), a fluorinated 4-quinolone, is often used clinically to treat infections associated with diabetis due to its antibacterial properties. It also modulates immune responses in human peripheral blood mononuclear cells (PBMC) therefore we investigated the involvement of AGEs in these effects. EXPERIMENTAL APPROACH Expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2 and CD40 was examined by flow cytometry. The production of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, prostaglandin E(2) (PGE(2)) and cAMP were determined by enzyme-linked immunosorbent assay. Cyclooxygenase (COX)-2 expression was determined by Western blot analysis. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake. KEY RESULTS CIP induced PGE(2) production in monocytes, irrespective of the presence of AGE-2 and AGE-3, by enhancing COX-2 expression; this led to an elevation of intracellular cAMP in monocytes. Non-selective and selective COX-2 inhibitors, indomethacin and NS398, inhibited CIP-induced PGE(2) and cAMP production. In addition, CIP inhibited AGE-2- and AGE-3-induced expressions of ICAM-1, B7.1, B7.2 and CD40 in monocytes, the production of TNF-alpha and IFN-gamma and lymphocyte proliferation in PBMC. Indomethacin, NS398 and a protein kinase A inhibitor, H89, inhibited the actions of CIP. CONCLUSIONS AND IMPLICATIONS CIP exerts immunomodulatory activity via PGE(2), implying therapeutic potential of CIP for the treatment of AGE-2- and AGE-3-induced inflammatory responses.

Prenatal interaction of mutant DISC1 and immune activation produces adult psychopathology

BACKGROUND

Gene-environment interactions (GEI) are involved in the pathogenesis of mental diseases. We evaluated interaction between mutant human disrupted-in-schizophrenia 1 (mhDISC1) and maternal immune activation implicated in schizophrenia and mood disorders.

METHODS

Pregnant mice were treated with saline or polyinosinic:polycytidylic acid at gestation day 9. Levels of inflammatory cytokines were measured in fetal and adult brains; expression of mhDISC1, endogenous DISC1, lissencephaly type 1, nuclear distribution protein nudE-like 1, glycoprotein 130, growth factor receptor-bound protein 2, and glycogen synthase kinase-3beta were assessed in cortical samples of newborn mice. Tissue content of monoamines, volumetric brain abnormalities, dendritic spine density in the hippocampus, and various domains of the mouse behavior repertoire were evaluated in adult male mice.

RESULTS

Prenatal interaction produced anxiety, depression-like responses, and altered social behavior that were accompanied by decreased reactivity of the hypothalamic-pituitary-adrenal axis, attenuated serotonin neurotransmission in the hippocampus, reduced enlargement of lateral ventricles, decreased volumes of amygdala and periaqueductal gray matter and density of spines on dendrites of granule cells of the hippocampus. Prenatal interaction modulated secretion of inflammatory cytokines in fetal brains, levels of mhDISC1, endogenous mouse DISC1, and glycogen synthase kinase-3beta. The behavioral effects of GEI were observed only if mhDISC1 was expressed throughout the life span.

CONCLUSIONS

Prenatal immune activation interacted with mhDISC1 to produce the neurobehavioral phenotypes that were not seen in untreated mhDISC1 mice and that resemble aspects of major mental illnesses. Our DISC1 mouse model is a valuable system to study GEI relevant to mental illnesses.

Histamine inhibits adhesion molecule expression in human monocytes, induced by advanced glycation end products, during the mixed lymphocyte reaction

BACKGROUND AND PURPOSE

Post-transplant diabetes mellitus is a frequent complication among transplant recipients. Ligation of advanced glycation end products (AGEs) with their receptor on monocytes/macrophages plays important roles in the genesis of diabetic complications. The enhancement of adhesion molecule expression on monocytes/macrophages activates T-cells, reducing allograft survival. Out of four distinct AGE subtypes (AGE-2, AGE-3, AGE-4 and AGE-5), only AGE-2 and AGE-3 induced expression of intercellular adhesion molecules (ICAMs), output of cytokines and proliferation of lymphocytes, during the mixed lymphocyte reaction (MLR). Here we have assessed the role of histamine in the actions of AGEs during the MLR.

EXPERIMENTAL APPROACH

Human peripheral blood cells were used in these experiments. Flow cytometry was used to examine the expression of the ICAM-1, B7.1, B7.2 and CD40. Production of the cytokine interferon-gamma, and levels of cAMP were determined by elisa. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake.

KEY RESULTS

Histamine concentration dependently inhibited the action of AGE-2 and AGE-3. The actions of histamine were antagonized by an H(2)-receptor antagonist, famotidine, and mimicked by H(2)/H(4)-receptor agonists, dimaprit and 4-methylhistamine. The effects of histamine were reversed by a protein kinase A (PKA) inhibitor, H89, and mimicked by dibutyryl cAMP and an adenylate cyclase activator, forskolin.

CONCLUSIONS AND IMPLICATIONS

Histamine down-regulated AGE-2- and AGE-3-induced expression of adhesion molecules, cytokine production and lymphocyte proliferation via histamine H(2) receptors and the cAMP/PKA pathway.

Formation of a three-dimensional network of V trimers in A2V13O22 (A=Ba, Sr)

We found that in A2V13O22 (A=Ba, Sr), which contains a trilayer slab of VO in the sodium-chloride structure with periodically missing ions, the trimerization of V ions occurs at 290 K (A=Ba) and 380 K (A=Sr). V trimers form a three-dimensional network, but some V ions remain untrimerized in these compounds. The suppression of magnetic susceptibility with trimerization and the existence of a Curie tail at low temperatures, together with the result of NMR measurement, indicate that the V trimers are spin singlet, whereas the untrimerized V ions have a magnetic moment; i.e., there is a spontaneous separation between nonmagnetic and magnetic ions in the crystal.

Ecological divergence and habitat isolation between two migratory forms of Japanese threespine stickleback (Gasterosteus aculeatus)

When two closely related species migrate to divergent spawning sites, divergent use of spawning habitats can directly reduce heterospecific mating. Furthermore, adaptations to divergent spawning habitats can promote speciation as a by-product of ecological divergence. Here, we investigated habitat isolation and ecological divergence between two anadromous forms of threespine stickleback (Gasterosteus aculeatus), the Japan Sea and Pacific Ocean forms. In several coastal regions of eastern Hokkaido, Japan, these forms migrate to the same watershed to spawn. Our field surveys in a single watershed revealed that segregation of distinct spawning sites between the two forms was maintained within the watershed across multiple years. These spawning sites diverged in salinity and predator composition. Morphological and physiological divergence between the forms also occurs in the direction predicted by ecological differences between the spawning sites. Our data indicate that migration into divergent spawning habitats can be an important mechanism contributing to speciation and phenotypic divergence in anadromous fishes.

A novel fibroblast growth factor-1 (FGF1) mutant that acts as an FGF antagonist

BACKGROUND

Crosstalk between integrins and FGF receptors has been implicated in FGF signaling, but the specifics of the crosstalk are unclear. We recently discovered that 1) FGF1 directly binds to integrin alphavbeta3, 2) the integrin-binding site and FGF receptor (FGFR) binding site are distinct, and 3) the integrin-binding-defective FGF1 mutant (R50E) is defective in inducing FGF signaling although R50E still binds to FGFR and heparin and induces transient ERK1/2 activation.

PRINCIPAL FINDINGS

We tested if excess R50E affect DNA synthesis and cell survival induced by WT FGF1 in BaF3 mouse pro-B cells expressing human FGFR1. R50E suppressed DNA synthesis and cell proliferation induced by WT FGF1. We tested if WT FGF1 and R50E generate integrin-FGF1-FGFR ternary complex. WT FGF1 induced ternary complex formation (integrin-FGF-FGFR1) and recruitment of SHP-2 to the complex in NIH 3T3 cells and human umbilical endothelial cells, but R50E was defective in these functions. It has been reported that sustained ERK1/2 activation is integrin-dependent and crucial to cell cycle entry upon FGF stimulation. We thus determined the time-course of ERK1/2 activation induced by WT FGF1 and R50E. We found that WT FGF1 induced sustained activation of ERK1/2, but R50E was defective in this function.

CONCLUSIONS/SIGNIFICANCE

Our results suggest that 1) R50E is a dominant-negative mutant, 2) Ternary complex formation is involved in FGF signaling, 3) The defect of R50E to bind to integrin may be directly related to the antagonistic action of R50E. Taken together, these results suggest that R50E has potential as a therapeutic in cancer.

Theoretical study of the cycloaddition reaction of a tungsten-containing carbonyl ylide

The [3+2] cycloaddition reaction of a tungsten-containing carbonyl ylide with methyl vinyl ether and the insertion reactions of the nonstabilized carbene complex intermediates produced have been investigated through the use of B3LYP density functional theory. The [3+2] cycloaddition reaction of the tungsten-containing carbonyl ylide has been proven to proceed concertedly, reversibly, and with high endo selectivity. The intermolecular Si-H insertion reactions of the carbene complex intermediates have been proven to be favored over the intramolecular C-H insertion, in good agreement with experimental results. Moreover, the kinetic endo/exo ratio of the [3+2] cycloaddition reaction has been shown to determine the endo/exo selectivity of the Si-H insertion products. In addition, secondary orbital interactions involving the benzene ring and the carbonyl ligand on the metal center have turned out to strongly influence the high endo selectivity of the [3+2] cycloaddition reaction with methyl vinyl ether.

Multiple photoreceptor systems control the swim pacemaker activity in box jellyfish

Like all other cnidarian medusae, box jellyfish propel themselves through the water by contracting their bell-shaped body in discrete swim pulses. These pulses are controlled by a swim pacemaker system situated in their sensory structures, the rhopalia. Each medusa has four rhopalia each with a similar set of six eyes of four morphologically different types. We have examined how each of the four eye types influences the swim pacemaker. Multiple photoreceptor systems, three of the four eye types, plus the rhopalial neuropil, affect the swim pacemaker. The lower lens eye inhibits the pacemaker when stimulated and provokes a strong increase in the pacemaker frequency upon light-off. The upper lens eye, the pit eyes and the rhopalial neuropil all have close to the opposite effect. When these responses are compared with all-eye stimulations it is seen that some advanced integration must take place.

Ferromagnetic domain nucleation and growth in colossal magnetoresistive manganite

Colossal magnetoresistance is a dramatic decrease in resistivity caused by applied magnetic fields, and has been the focus of much research because of its potential for magnetic data storage using materials such as manganites. Although extensive microscopy and theoretical studies have shown that colossal magnetoresistance involves competing insulating and ferromagnetic conductive phases, the mechanism underlying the effect remains unclear. Here, by directly observing magnetic domain walls and flux distributions using cryogenic Lorentz microscopy and electron holography, we demonstrate that an applied magnetic field assists nucleation and growth of an ordered ferromagnetic phase. These results provide new insights into the evolution dynamics of complex domain structures at the nanoscale, and help to explain anomalous phase separation phenomena that are relevant for applications. Our approach can also be used to determine magnetic parameters of nanoscale regions, such as magnetocrystalline anisotropy and exchange stiffness, without bulk magnetization results or neutron scattering data.

UV resonance Raman studies on the activation mechanism of human hematopoietic prostaglandin D(2) synthase by a divalent cation, Mg(2+)

The Mg(2+) ion-assisted activation mechanism of the active site Tyr8 of a human hematopoietic prostaglandin D(2) synthase (H-PGDS) was studied by ultraviolet resonance Raman (UVRR) spectroscopy. Addition of Mg(2+) to the native H-PGDS at pH 8.0 resulted in the Y8a Raman band of Tyr8 shifting from 1615cm(-1) to 1600cm(-1). This large shift to lower energy of the tyrosine Y8a vibrational mode is caused by the deprotonation of the tyrosine phenol group promoted by binding of Mg(2+). Upon subsequent addition of glutathione (GSH), the Mg(2+)/H-PGDS solution showed the Tyr8 Raman band shifted to 1611cm(-1), which is 11cm(-1) higher than the frequency of the Mg(2+) complex of H-PGDS, but 4cm(-1) lower than the Mg(2+) free enzyme. These UVRR observations suggest that the deprotonated Tyr8 in the presence of Mg(2+) is re-protonated by the abstraction of H(+) from the thiol group of GSH, and that the re-protonated Tyr8 species forms a hydrogen bond with the thiolate anion of GSH. Density functional theory calculations on several model complexes of p-cresol were also performed, which suggested that the pK(a) and vibrational frequencies of the Tyr8 phenol group are affected by the degree and structure of hydration of the Tyr8 residue.

A randomized controlled trial of plasma real-time PCR and antigenemia assay for monitoring CMV infection after unrelated BMT

Preemptive therapy is the standard strategy for preventing CMV disease after allogeneic hematopoietic SCT. In this study, unrelated BMT recipients were randomly assigned to a plasma real-time PCR group or an antigenemia group to compare the value of these monitoring tools for CMV reactivation. Ganciclovir (GCV) was started at 5 mg/kg/day when PCR reached 300 copies per ml or when antigenemia reached three positive cells per two slides. A total of 88 patients were randomized into the antigenemia group (n=45) or the PCR group (n=43). A significantly higher number of patients reached the threshold in the antigenemia group than in the PCR group (73.3 vs 44.2%, P=0.0089). However, only three patients (one in the antigenemia group and two in the PCR group) developed early CMV disease. These patients exclusively had colitis and were successfully treated with GCV or foscarnet. The median number of antigenemia-positive cells at the start of GCV was 47 in the PCR group. These findings suggest that antigenemia assay with the current cutoff was too sensitive and led to unnecessary use of GCV. However, the appropriateness of the threshold may be different by the methodology used, and therefore, it is difficult to generalize.

Sea-run migratory behaviour in the Japan Sea form of three-spined stickleback Gasterosteus aculeatus in the tidal pool of eastern Hokkaido Island, Japan

Juveniles in the Japan Sea form of three-spined stickleback Gasterosteus aculeatus collected from a tidal pool in eastern Hokkaido Island, Japan, had a unimodal standard length (L(S)) frequency distribution in each period, ranging from 11.9 to 31.6 mm, and those of sea-run migrating individuals collected from the outlet of this tidal pool ranged from 17.0 to 36.0 mm, suggesting juveniles of this form would migrate towards the sea when they reached >17.0 mm. In general linear models (GLM) for testing the best model, there was a relationship between the number of sea-run migratory individual and precipitation, which suggests that precipitation may trigger migration.

Periodontal gene transfer by ultrasound and nano/microbubbles

A non-viral gene delivery approach with nano/microbubbles and ultrasound offers opportunities for targeting soft tissues for gene therapy. The periodontium is a complex structure comprised of hard (cementum, alveolar bone) and soft tissues (periodontal ligament, gingivae). We hypothesized that our established gene delivery method would allow the periodontal tissue to be targeted for transfection for gene therapy. Expression kinetics and sites of transfection sites with this approach were investigated in rat periodontal tissue. Bioluminescence imaging revealed that transient gene expression was induced at day 1 posttransfection, while confocal microscopy showed that gene expression was localized in the muscle cells of gingival tissues. These findings indicate that regular transfection with this approach results in high gene expression, facilitating gene therapy for periodontal disease involving alveolar bone resorption.

White matter impairment in Rett syndrome: diffusion tensor imaging study with clinical correlations

BACKGROUND AND PURPOSE

RTT, caused by mutations in the methyl CPG binding protein 2 (MeCP2) gene, is a disorder of neuronal maturation and connections. Our aim was to prospectively examine FA by DTI and correlate this with certain clinical features in patients with RTT.

MATERIALS AND METHODS

Thirty-two patients with RTT underwent neurologic assessments and DTI. Thirty-seven age-matched healthy female control subjects were studied for comparison. With use of a 1.5T MR imaging unit, DTI data were acquired, and FA was evaluated to investigate multiple regional tract-specific abnormalities in patients with RTT.

RESULTS

In RTT, significant reductions in FA were noted in the genu and splenium of the corpus callosum and external capsule, with regions of significant reductions in the cingulate, internal capsule, posterior thalamic radiation, and frontal white matter. In contrast, FA of visual pathways was similar to control subjects. FA in the superior longitudinal fasciculus, which is associated with speech, was equal to control subjects in patients with preserved speech (phrases and sentences) (P = .542), whereas FA was reduced in those patients who were nonverbal or speaking only single words (P < .001). No correlations between FA values for tracts and clinical features such as seizures, gross or fine motor skills, and head circumference were identified.

CONCLUSIONS

DTI, a noninvasive technique to assess white matter tract pathologic features, may add specificity to the assessment of RTT clinical severity that is presently based on the classification of MeCP2 gene mutation and X-inactivation.

Pneumocystis-associated organizing pneumonia as a manifestation of immune reconstitution inflammatory syndrome in an HIV-infected individual with a normal CD4+ T-cell count following antiretroviral therapy

We describe a rare case of Pneumocystic jirovecii-associated organizing pneumonia (PJP) in an HIV-infected individual on highly active antiretroviral therapy (HAART) with a CD4(+) T-cell count of 835 x 10(3) cells/mL and a low viral load. PJP was confirmed using transbronchial biopsies and bronchoalveolar lavage. The presentation in this patient suggests immune reconstitution inflammatory syndrome (IRIS) after institution of antiretroviral therapy (ART). This case report, however, is the first documented presentation of PJP in a patient with CD4 count greater than 300 prior to the induction of HAART who developed PJP and organizing pneumonia as a manifestation of IRIS. This suggests that there is continuing immune dysfunction in the face of re-expansion of CD4(+) T-cells and low viral load in HIV patients despite ART.

Production of positron emitters of metallic elements to study plant uptake and distribution

The metallic positron emitters 52Mn, 52Fe and 62Zn, the elements of which are essential nutrients for plants as well as for animals, have been produced for a new tracer method in plant physiology. The tracer method utilizes the detection of annihilation γ-rays, like PET in nuclear medicine, to obtain two-dimensional images on a plant as well as to obtain radioactivity counts at specified points in a plant; this method allows us to observe the tracer movement in a living plant without touching the test plant. The previously reported methods of radiochemical separation of these metallic positron emitters from targets were partly modified from the view of their use in plant physiology. Radionuclidic impurities remaining in the final solutions were examined by γ-ray spectrometry, and their influences on the above-mentioned measurements are discussed. From the experiments on a barley plant, the speeds of 52Mn2+ ion and 52Fe3+-mugineic-acid complex have been obtained for the first time to be 0.2 cm/min and 1.0 cm/min, respectively.

A brief review of potential mechanisms of immune reconstitution inflammatory syndrome in HIV following antiretroviral therapy

A subset of HIV-infected individuals who receive antiretroviral therapy (ART) develop a paradoxical pathological response that significantly increases morbidity and sometimes mortality. Following the induction of highly active ART, a rapid decline in the viral load results within weeks and coincides with a steep rise in the CD4(+) T-cell counts and immune hyperactivation. Although no mechanistic pathway has been elucidated for the development of immune reconstitution inflammatory syndrome (IRIS), it is thought that change in the nature of the immune response is a predominant factor in the development of reconstitution disease. In this article, we review the current state of knowledge in this field and provide a model for the development of IRIS.

Diffusion tensor imaging may help the determination of time at onset in cerebral ischaemia

BACKGROUND AND AIMS

The apparent diffusion coefficient (ADC) and anisotropy (eg, fractional anisotropy (FA)) of ischaemic tissue evolve over time. A reduction in diffusivity (ie, lambda(2) and lambda(3)) is an important marker for characterising hyperacute-stage infarction, as these parameters may reflect axonal membrane status. The study examines whether transverse diffusivity could be useful in assessing white matter infarcts of various ages.

METHODS

Diffusion tensor imaging data from 44 adult patients (34 men, 10 women, aged 46 to 89 years, mean = 70.3) with acute white matter infarction (1-168 h) of the internal capsule were analysed. Relative eigenvalues were calculated as: (lambda(ipsi)-lambda(contra))/lambda(contra). Lesions were classified based on theoretically expected evolution of diffusivity over time as follows: stage I, FA higher than the contralesional region of interest (ROI); stage II, diffusivity lower than the contralesional side for all eigenvalues; stage III, one of two transverse eigenvalues (lambda(2) or lambda(3)) higher than the contralesional ROI.

RESULTS

Stage I infarcts (n = 5) were found primarily within 24 h of the onset of symptoms, with one case found on the third day. Stage II infarcts were found most commonly within 24 h (n = 18), and fewer after 24 h. After the first day, the ratio of stage III infarcts increased significantly. Thus, diffusivity-based classification of white matter infarcts seems to show a chronological trend.

CONCLUSIONS

Diffusion anisotropy may be useful for defining the biological tissue clock of white matter infarctions.

Anchorage-independent cell growth signature identifies tumors with metastatic potential

The oncogenic phenotype is complex, resulting from the accumulation of multiple somatic mutations that lead to the deregulation of growth regulatory and cell fate controlling activities and pathways. The ability to dissect this complexity, so as to reveal discrete aspects of the biology underlying the oncogenic phenotype, is critical to understanding the various mechanisms of disease as well as to reveal opportunities for novel therapeutic strategies. Previous work has characterized the process of anchorage-independent growth of cancer cells in vitro as a key aspect of the tumor phenotype, particularly with respect to metastatic potential. Nevertheless, it remains a major challenge to translate these cell biology findings into the context of human tumors. We previously used DNA microarray assays to develop expression signatures, which have the capacity to identify subtle distinctions in biological states and can be used to connect in vitro and in vivo states. Here we describe the development of a signature of anchorage-independent growth, show that the signature exhibits characteristics of deregulated mitochondrial function and then demonstrate that the signature identifies human tumors with the potential for metastasis.