Relation Between Asymmetry of Prefrontal Activity and Autonomic Nervous System in Post-stroke Patients with a Disorder of Consciousness.

Early mobilization and rehabilitation of stroke patients can improve functional recovery. However, effects of mobilization on the responses of the autonomic nervous system (ANS) and emotions in post-stroke patients are not yet clear, particularly in patients with disorders of consciousness. We evaluated the effects of standing load on the ANS and emotions of post-stroke patients (n = 8, 70.8 ± 11.8 years) with a disorder of consciousness by measuring the prefrontal cortex (PFC) activity, which plays important roles in regulation of the ANS and emotions. Employing near infrared spectroscopy (NIRS), we measured concentration changes of oxygenated haemoglobin (oxy-Hb) in the PFC for 10 min at rest. Then, subjects were placed in supine position on a tilt table, and standing loads were given by 30°, 45° and 60° every 5 min. We assessed left-right asymmetry of the PFC activity at rest by calculating the Laterality Index at Rest (LIR; LIR>0 indicates right dominant activity while LIR<0 indicates left dominant activity). We observed fluctuations of oxy-Hb in the PFC at rest, indicating activation of the PFC. Interestingly, 75% (six patients) of the patients exhibited right dominant PFC activation at rest. These patients exhibited an increase of oxy-Hb during standing load; four patients suffered from orthostatic hypotension. Finally, there was a significant positive correlation between LIR before the standing test and oxy-Hb changes during the standing test (r = 0.78, p = 0.02). These results suggest that the standing load might act on post-stroke patients as a stressor, which caused an increase of PFC activity (i.e., rCBF). NIRS may be useful to assess feasibility to start rehabilitation of post-stroke patients with a disorder of consciousness.

Effects of Motor Imagery on Cognitive Function and Prefrontal Cortex Activity in Normal Adults Evaluated by NIRS.

Recent near-infrared spectroscopy (NIRS) studies demonstrated that physical exercise enhances working memory (WM) performance and prefrontal cortex (PFC) activity during WM tasks in normal adults. Interestingly, the effects of rehabilitation (i.e. physiotherapy) on post-stroke patients could be enhanced by motor imagery (MI), an active process during which the specified action is reproduced within WM without any actual physical movement. However, it is not known whether MI can enhance cognitive function and associated brain activity. To clarify these issues, we evaluated the effect of MI on WM performance and PFC activity during WM tasks in normal adults, employing NIRS. We studied 10 healthy adults. The present study was a crossover comparison test; the MI training and control condition (rest) were applied to the subjects at random. The Time Up and Go method was used for MI training: the subject sat on a chair and conducted MI for 3 min, three times. Neuronal activity (oxyhemoglobin concentration) in the bilateral PFC was measured using 2-CH NIRS during WM tasks. We found that MI improved the behavioral performance of WM compared with the control (p < 0.01). NIRS revealed that MI enhanced PFC activity induced by the WM task compared with the control task (p < 0.01). These results suggest that MI can improve cognitive function and increase associated PFC activity in normal adults.

Effects of Physical Exercise on Working Memory and Prefrontal Cortex Function in Post-Stroke Patients.

Physical exercise enhances prefrontal cortex activity and improves working memory performance in healthy older adults, but it is not clear whether this remains the case in post-stroke patients. Therefore, the aim of this study was to examine the acute effect of physical exercise on prefrontal cortex activity in post-stroke patients using near-infrared spectroscopy (NIRS). We studied 11 post-stroke patients. The patients performed Sternberg-type working memory tasks before and after moderate intensity aerobic exercise (40 % of maximal oxygen uptake) with a cycling ergometer for 15 min. We measured the NIRS response at the prefrontal cortex during the working memory task. We evaluated behavioral performance (response time and accuracy) of the working memory task. It was found that physical exercise improved behavioral performance of the working memory task compared with the control condition (p < 0.01). In addition, NIRS analysis indicated that physical exercise enhanced prefrontal cortex activation, particularly in the right prefrontal cortex (p < 0.05), during the working memory task compared with the control condition. These findings suggest that the moderate-intensity aerobic exercise enhances prefrontal cortex activity and improves working memory performance in post-stroke patients.

Use of Chironomidae (Diptera) Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies.

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. Unfortunately, traditional benthic larval sampling methods, such as the dip-net, can be time-consuming and expensive. An alternative protocol involves collection of Chironomidae surface-floating pupal exuviae (SFPE). Chironomidae is a species-rich family of flies (Diptera) whose immature stages typically occur in aquatic habitats. Adult chironomids emerge from the water, leaving their pupal skins, or exuviae, floating on the water's surface. Exuviae often accumulate along banks or behind obstructions by action of the wind or water current, where they can be collected to assess chironomid diversity and richness. Chironomids can be used as important biological indicators, since some species are more tolerant to pollution than others. Therefore, the relative abundance and species composition of collected SFPE reflect changes in water quality. Here, methods associated with field collection, laboratory processing, slide mounting, and identification of chironomid SFPE are described in detail. Advantages of the SFPE method include minimal disturbance at a sampling area, efficient and economical sample collection and laboratory processing, ease of identification, applicability in nearly all aquatic environments, and a potentially more sensitive measure of ecosystem stress. Limitations include the inability to determine larval microhabitat use and inability to identify pupal exuviae to species if they have not been associated with adult males.

Analysis of TP53 mutation spectra reveals the fingerprint of the potent environmental carcinogen, aristolochic acid.

Genetic alterations in cancer tissues may reflect the mutational fingerprint of environmental carcinogens. Here we review the pieces of evidence that support the role of aristolochic acid (AA) in inducing a mutational fingerprint in the tumor suppressor gene TP53 in urothelial carcinomas of the upper urinary tract (UUT). Exposure to AA, a nitrophenathrene carboxylic acid present in certain herbal remedies and in flour prepared from wheat grain contaminated with seeds of Aristolochia clematitis, has been linked to chronic nephropathy and UUT. TP53 mutations in UUT of individuals exposed to AA reveal a unique pattern of mutations characterized by A to T transversions on the non-transcribed strand, which cluster at hotspots rarely mutated in other cancers. This unusual pattern, originally discovered in UUTs from two different populations, one in Taiwan, and one in the Balkans, has been reproduced experimentally by treating mouse cells that harbor human TP53 sequences with AA. The convergence of molecular epidemiological and experimental data establishes a clear causal association between exposure to the human carcinogen AA and UUT. Despite bans on the sale of herbs containing AA, their use continues, raising global public health concern and an urgent need to identify populations at risk.

Mechanism of the anti-obesity effects induced by a novel melanin-concentrating hormone 1-receptor antagonist in mice.

BACKGROUND AND PURPOSE: Melanin-concentrating hormone (MCH) is an orexigenic neuropeptide expressed in the lateral hypothalamus that is involved in feeding and body weight regulation. Intracerebroventricular infusion of a peptidic MCH1 receptor antagonist ameliorated obesity in murine models. Recently, small molecule MCH1 receptor antagonists have been developed and characterized for the treatment of obesity. However, little is known of the mechanism of the anti-obesity effects of MCH1 receptor antagonists. EXPERIMENTAL APPROACH: To examine the mechanisms of action of the anti-obesity effect of MCH1 receptor antagonists more precisely, we conducted a pair-feeding study in mice with diet-induced obesity (DIO), chronically treated with an orally active and highly selective MCH1 receptor antagonist and examined changes in mRNA expression levels in liver, brown and white adipose tissues. We also assessed the acute effects of the MCH1 receptor antagonist in energy expenditure under thermoneutral conditions. KEY RESULTS: Treatment with the MCH1 receptor antagonist at 30 mg.kg(-1) for 1 month moderately suppressed feeding and significantly reduced body weight by 24%. In contrast, pair-feeding resulted in a smaller weight reduction of 10%. Treatment with the MCH1 receptor antagonist resulted in a higher body temperature compared with the pair-fed group. TaqMan and calorimetry data suggested that the MCH1 receptor antagonist also stimulated thermogenesis. CONCLUSIONS AND IMPLICATIONS: Our results indicate that an MCH1 receptor antagonist caused anti-obesity effects im mice by acting on both energy intake and energy expenditure.

A 12 month in vivo study on the response of bone to a hydroxyapatite-polymethylmethacrylate cranioplasty composite.

We investigated the osteoconductivity and biocompatibility in vivo of a new hydroxyapatite-polymethylmethacrylate (HA-PMMA) composite developed for use as an implant material for cranioplasty, which is expected to have the good osteoconductivity of HA together with the strength and ease of handling of PMMA. The HA-PMMA composites were implanted in eight full-grown beagles and then 6, 12, 24 weeks and 1 year after implantation, the animals were sacrificed and the implanted materials removed along with the surrounding tissues. Extirpated specimens were studied using an optical microscope and micro-computed tomography (micro-CT). Fibrous connective tissue was prominent in the interface of the composite at 6 weeks. New bone formation was seen around the implant, 12 and 24 weeks after operation. At 1 year, new bone filled in the interface of the HA-PMMA composite and adhered to the surrounding autogenous bone. Mixing HA and PMMA did not interfere with the osteoconductivity of the HA component. In micro-CT findings, the new bone growing on the HA-PMMA composite could be seen attaching preferentially to HA particles exposed at the composite surface, rather than the PMMA. This study demonstrated that this HA-PMMA composite is a good candidate for cranial bone implants due to its good osteoconductivity and biocompatibility.

Beneficial effect of interferon-beta treatment in patients with multiple sclerosis is associated with transient increase in serum IL-6 level in response to interferon-beta injection.

In order to predict the clinical benefit of interferon-beta (IFN-beta) to patients with multiple sclerosis (MS), the following markers were investigated; (1) chronological change of cytokines (IFN-gamma, TNF-alpha, IL-6, IL-10, and TGF-beta) after administration of IFN-beta, (2) untoward effects of IFN-beta such as headache and arthralgia, (3) backgrounds of the patients such as age and relapse rate, (4) efficacy of IFN-beta therapy assessed by the change of relapse rate and progression of disability. Chronological blood sampling was performed 0, 10, and 24 h after injection of IFN-beta. The increase of serum IL-6 level in response to IFN-beta administration was associated with headache, arthralgia, relapse rate before treatment, and disability score at the initiation of the therapy. Significant association of change of serum TNF-alpha with age and headache was also observed. The important finding in this study was that patients with a transient increase in IL-6 in response to IFN-beta showed a slow disease progression. This result suggests that this transient increase in the serum IL-6 predicts favorable response to IFN-beta treatment.

Analysis of parameter variations in L-Q equations for river runoff processes from the viewpoint of spatial and temporal conditions.

This study aims to find out variation characteristics of the parameters of 'a' and 'b' in L = a x Q(b), an empirical equation for run-off loading (L) and flow rate (Q), by evaluating the effects of flow conditions and regional properties of the watersheds on the values. We selected the Kamo River basin (155 km2) as a study field, and conducted various kinds of investigations, such as 80 day high frequency observations, continuous monitoring for more than 2 years, storm event surveys, and simultaneous surveys of 39 stations. Then, we obtained 7-170 data in each of 39 sampling stations. The main results obtained are as follows: (1) L-Q equation with a range of 'a' can express L-Q relation in most of the WQIs (water quality indices); (2) 'a' receives temporal (flow condition) effects more in SS, VSS and Al, while it receives regional effect more in inorganic carbon, TN, Ca and Fe; (3) both of flow change in storm events, and base flow levels affect the L-Q relation, and their effects can classify the WQIs into several groups; (4) the effects of regional properties were obviously observed in 'a', and quantitatively evaluated, especially for density of population.

The effect of hematoma removal for reducing the development of brain edema in cases of putaminal hemorrhage.

INTRODUCTION: Surgical intervention in putaminal hemorrhage has been a controversial issue. The aim of this research is to evaluate the benefits of surgery for reducing the development of brain edema. MATERIALS AND METHODS: Sixteen cases of putaminal hemorrhage were examined. Eight patients were treated conservatively (C group), and the other 8 patients were treated surgically (S group). Head CT scans were performed on the day of onset (day 0) in C group or performed just after surgery (day 0) in S group, and performed again once per period on days 1-7, 8-14, and 15-21. The volume of the mass including hematoma and edema (H + E) was measured using CT scans and the (H + E)/H0 ratios were calculated (H0; hematoma volume on day 0). The (H + E)/H0 ratios for each period were compared statistically between the 2 groups using a t-test. RESULTS: The mean values of(H + E)/H0 ratios at each period were 2.19, 2.63, 2.53 in C group, and 1.29, 1.29, 0.66 in S group. The values in S group were significantly lower as compared with C group in every period (p < 0.01, < 0.05, < 0.01). CONCLUSIONS: Hematoma volume reduction by surgery reduced the development of brain edema.

Progressive expression of vascular endothelial growth factor (VEGF) and angiogenesis after chronic ischemic hypoperfusion in rat.

Cerebrovascular stenosis caused by arteriosclerosis induces failure of the cerebral circulation. Even if chronic cerebral hypoperfusion does not induce acute neuronal cell death, cerebral hypoperfusion may be a risk factor for neurodegenerative diseases. The purpose of this study was to determine if vasodilation, expression of VEGF, and neovascularization are homeostatic signs of cerebral circulation failure after permanent common carotid artery occlusion (CCAO) in the rat. Neuronal cell death in neocortex was observed 2 weeks after CCAO and gradually increased in a time-dependent manner. The diameter of capillaries and expression of VEGF also increased progressively after CCAO. Moreover, we observed unusual irregular angiogenic vasculature at 4 weeks. In conclusion, chronic hypoperfusion results in mechanisms to compensate for insufficiency in blood flow including vasodilation, VEGF expression, and neovascularization in the ischemic region. These results suggest that angiogenesis might be induced in adult brain through the support of growth factors and transplantation of vascular progenitor cells, and that neovascularization might be a therapeutic strategy for children and adults with diseases such as vascular dementia.

Estimation of annual pollutant loadings in two small catchments and examination of their differences caused by regional properties.

A series of runoff surveys was conducted for more than one year in two small catchments of the Kamo River basin (75.4 km2) and the Takano River basin (66.8 km2) in Kyoto, Japan, which adjoin each other, and may have the same precipitation pattern. The investigation consisted of a high-frequency periodic survey, a long-term regular survey and a storm event survey. The survey results were compared with the regional properties of the basins, and the following results were obtained. (1) Pollutant loadings were successfully estimated as two portions of base discharge and storm events discharge from the survey results. (2) Estimated annual loading of the sites was 2.9-4.5, 1.3-1.8, 17-27, 1.3-2.2, 0.076-0.97 t/km2/y, respectively for COD(Mn), DOC, SS, TN and TP. (3) 52-53% of the whole flow, which was caused by rainfall events, conveyed 81-87, 68-73, 92-95, 64-67, 76-81% of the whole loading, respectively for COD(Mn), DOC, SS, TN and TP. (4) Differences of regional properties in two basins cause different runoff patterns, but the differences in runoff patterns also depend on the rainfall patterns. In general, a more urbanized basin receives early and strong influence of precipitation on the storm event runoff.

Cimicifuga racemosa L., Trifolium pratense L. e Vitex agnus-castus L.: a correspondência das indicações contida nas bulas dos fitoterápicos e o respaldo científico / Cimicifuga racemosa L., Trifolium pratense L. and Vitex agnus-castus L.: the degree of correspondence between instructions supplied with herbal medical preparations and relevant scientific data

É cada vez maior o número de mulheres que utilizam fitoterápicos como terapia alternativa para a menopausa, entretanto, na maioria das vezes esses produtos não possuem um mecanismo de ação conhecido, tão pouco eficácia clinica comprovada. O presente estudo objetiva avaliar a correspondência das indicações clínicas e os achados científicos de três produtos fitoterápicos de elevado índice de vendas na região de Piracicaba, destinados ao alívio dos sintomas da menopausa. Para isso foi realizado um levantamento dos fitoterápicos com maior venda numa farmácia pertencente a uma grande rede e lista das as plantas medicinais que compunham esses medicamentos. Posteriormente, verificou-se no Dicionário de Especialidades Farmacêuticas (DEF) 2004/05 todos fitoterápicos que tinham em sua composição pelo menos uma das três plantas medicinais selecionadas (Cimicifuga racemosa L., Trifolium pratense L. e Vitex agnus-castus L.) e feito um levantamento de como estavam registrados na ANVISA. Para análise da segurança do uso e eficácia dessas plantas medicinais fez-se uma busca em bases de dados científicos MEDLINE procurando trabalhos pré-clínicos de toxicidade e clínicos controlados randomizados que comprovassem a indicação terapêutica da planta. Dentre os resultados encontrados obteve-se que nenhum trabalho sobre toxicidade referia-se a segurança do uso da planta. Quanto a eficácia, das sete indicações propostas pelo fabricante do medicamento que contém a Cimicifugaracemosa L., somente uma das indicações se confirmava em estudo publicado; das nove indicações descritas na bula da Vitex agnus-castus L., duas se confirmavam através de pesquisas realizadas; e, das sete listadas para a Trifolium pratense L., uma foi comprovada.

The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7-3946.

Protons with energies up to approximately 10(15) eV are the main component of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking. Electrons are known to be accelerated to cosmic-ray energies in supernova remnants, and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution. Here we report the observation of cascade showers of optical photons resulting from gamma-rays at energies of approximately 10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

Dicationic dithiocarbamate carbapenems with anti-MRSA activity.

A new class of 1 beta-methylcarbapenems bearing a doubly quaternarized 1,4-diazabicyclooctane (DABCO) substituted dithiocarbamate moiety at the C-2 side chain was prepared, and the biological profiles of the compounds, including in vitro and in vivo anti-MRSA activity and DHP-I susceptibility, were evaluated to identify a carbapenem derivative that was superior to BO-3482 (1). As a result, we discovered a 1 beta-methyl-2-[4-(4-carbamoylmethyl-1,4-diazabicyclo[2,2,2]octanediium-1-yl)methyl-1,2,3,6-tetrahydropyridinylthiocarbonylthio]carbapenem, 14a showing greater than 2-fold better anti-MRSA activity in a mouse infection model and 3-fold better DHP-I susceptibility as compared with BO-3482 (1).

Translesion DNA synthesis catalyzed by human pol eta and pol kappa across 1,N6-ethenodeoxyadenosine.

1,N(6)-Ethenodeoxyadenosine, a DNA adduct generated by exogenous and endogenous sources, severely blocks DNA synthesis and induces miscoding events in human cells. To probe the mechanism for in vivo translesion DNA synthesis across this adduct, in vitro primer extension studies were conducted using newly identified human DNA polymerases (pol) eta and kappa, which have been shown to catalyze translesion DNA synthesis past several DNA lesions. Steady-state kinetic analyses and analysis of translesion products have revealed that the synthesis is >100-fold more efficient with pol eta than with pol kappa and that both error-free and error-prone syntheses are observed with these enzymes. The miscoding events include both base substitution and frameshift mutations. These results suggest that both polymerases, particularly pol eta, may contribute to the translesion DNA synthesis events observed for 1,N(6)-ethenodeoxyadenosine in human cells.

Responses to the major acrolein-derived deoxyguanosine adduct in Escherichia coli.

Acrolein, a reactive alpha,beta-unsaturated aldehyde found ubiquitously in the environment and formed endogenously in mammalian cells, reacts with DNA to form an exocyclic DNA adduct, 3H-8-hydroxy-3-(beta-D-2'-deoxyribofuranosyl)-5,6,7,8-tetrahydropyrido[3,2-a]purine-9-one (gamma-OH-PdG). The cellular processing and mutagenic potential of gamma-OH-PdG have been examined, using a site-specific approach in which a single adduct is embedded in double-strand plasmid DNA. Analysis of progeny plasmid reveals that this adduct is excised by nucleotide excision repair. The apparent level of inhibition of DNA synthesis is approximately 70% in Escherichia coli DeltarecA, uvrA. The block to DNA synthesis can be overcome partially by recA-dependent recombination repair. Targeted G --> T transversions were observed at a frequency of 7 x 10(-4)/translesion synthesis. Inactivation of polB, dinB, and umuD,C genes coding for "SOS" DNA polymerases did not affect significantly the efficiency or fidelity of translesion synthesis. In vitro primer extension experiments revealed that the Klenow fragment of polymerase I catalyzes error-prone synthesis, preferentially incorporating dAMP and dGMP opposite gamma-OH-PdG. We conclude from this study that DNA polymerase III catalyzes translesion synthesis across gamma-OH-PdG in an error-free manner. Nucleotide excision repair, recombination repair, and highly accurate translesion synthesis combine to protect E. coli from the potential genotoxicity of this DNA adduct.

Immunohistochemical detection of calmodulin and calmodulin-dependent protein kinase II in the mouse testis.

We reported previously that in mouse testis calmodulin-dependent protein phosphatase (calcineurin) is localised in the nuclei of round and elongating spermatids (Cell Tissue Res. 1995; 281: 273-81). In this study, we studied the immunohistochemical localisation of calcium/calmodulin-dependent protein kinase (CaM kinase II) using antibodies against CaM kinase IIgamma from chicken gizzard and specific antibodies raised against the amino acid sequence Ileu480-Ala493 of this enzyme, and compared it with the distribution of calmodulin. Indirect immunofluorescence was most concentrated in early spermatocytes and localised in the outermost layer of seminiferous tubules where the calmodulin level was relatively low. Measurements of immuno-gold particle densities on electron micrographs revealed that CaM kinase II is transiently increased in the nucleus of zygotene spermatocytes. These observations suggest the involvement of CaM kinase II in the meiotic chromosomal pairing process. An extremely high concentration of calmodulin in spermatogenic cells undergoing meiosis may not be directly related to activation of calmodulin-dependent kinases and phosphatases.

Escherichia coli responses to a single DNA adduct.

To study the mechanisms by which Escherichia coli modulates the genotoxic effects of DNA damage, a novel system has been developed which permits quantitative measurements of various E. coli pathways involved in mutagenesis and DNA repair. Events measured include fidelity and efficiency of translesion DNA synthesis, excision repair, and recombination repair. Our strategy involves heteroduplex plasmid DNA bearing a single site-specific DNA adduct and several mismatched regions. The plasmid replicates in a mismatch repair-deficient host with the mismatches serving as strand-specific markers. Analysis of progeny plasmid DNA for linkage of the strand-specific markers identifies the pathway from which the plasmid is derived. Using this approach, a single 1, N(6)-ethenodeoxyadenosine adduct was shown to be repaired inefficiently by excision repair, to inhibit DNA synthesis by approximately 80 to 90%, and to direct the incorporation of correct dTMP opposite this adduct. This approach is especially useful in analyzing the damage avoidance-tolerance mechanisms. Our results also show that (i) progeny derived from the damage avoidance-tolerance pathway(s) accounts for more than 15% of all progeny; (ii) this pathway(s) requires functional recA, recF, recO, and recR genes, suggesting the mechanism to be daughter strand gap repair; (iii) the ruvABC genes or the recG gene is also required; and (iv) the RecG pathway appears to be more active than the RuvABC pathway. Based on these results, the mechanism of the damage avoidance-tolerance pathway is discussed.