Estimation of cognitive impairment in chronic pain patients and characteristics of estimated mild cognitive impairment

Background

Patients with chronic pain suffer from psychological effects such as anxiety due to the pain itself. Pain can not only impair activities of daily living (ADL) and quality of life (QOL), but also impair cognitive function. Therefore, in this study, we aimed to estimate the cognitive function of chronic pain patients using a deep neural network (DNN) model that has already been implemented in society. We investigated the characteristics of patients presumed to have mild cognitive impairment (MCI) and, at the same time, verified the relationship with the questionnaire commonly used in chronic pain research, which is administered by 43 university affiliated hospitals and medical institutions participating in the chronic pain research group of the Ministry of Health, Labor and Welfare in Japan (assessment batteries).

Method

The study included 114 outpatients from a multidisciplinary pain clinic, and we estimated their Mini-Mental State Examination (MMSE) scores based on age and basic blood test data (23 items). Furthermore, we classified the estimated MMSE scores of chronic pain patients into two groups based on a cutoff score of 27, which indicates MCI, and compared the blood data and assessment batteries. Additionally, we used a control group of 252 healthy adults aged 45 years or older who visited a dementia prevention outpatient clinic for comparison with the MMSE scores of chronic pain patients.

Result

The MMSE scores in chronic pain patients were below the cutoff for MCI. When classified into two groups based on the estimated MMSE score of 27 points, WBC, RBC, Hb, Hct, PLT, UA, BUN, creatinine, Triglyceride, and γ-GT were significantly higher in the blood data. In the MCI group, PDAS values were significantly lower. Furthermore, only in the non-MCI group, a significant correlation was found between the estimated MMSE value and BPI, PDAS, and Locomo. The estimated MMSE scores were significantly lower in chronic pain patients than in healthy adults (p = 0.04).

Conclusion

Patients with chronic pain may exhibit cognitive impairment due to systemic metabolic disturbances. This suggests that chronic pain affects activities of daily living, resulting in systemic metabolic disorders.

Bifidobacterium breve M-16V regulates the autonomic nervous system via the intestinal environment: A double-blind, placebo-controlled study

We conducted a randomized controlled trial to investigate the potential of Bifidobacterium breve M-16 V to improve mood in humans. In this evaluation, we incorporated the use of near-infrared spectroscopy (NIRS), which has been used to evaluate mood states in studies with small sample sizes. Participants were given B. breve M-16 V (20 billion cells/day) for 6 weeks, and their mood state was assessed before and after ingestion. NIRS data were collected at rest and during a mental arithmetic task (under stress). Intake of B. breve M-16 V decreased the heart rate under stress and increased levels of the GABA-like substance pipecolic acid in stool samples. In addition, B. breve M-16 V improved mood and sleep scores in participants with high anxiety levels. These results suggest that B. breve M-16 V affects the metabolites of the gut microbiota and has the potential to modulate the autonomic nervous system and to improve mood and sleep.

Association Between Early Mobilization and Functional Outcomes in Patients with Aneurysmal Subarachnoid Hemorrhage: A Multicenter Retrospective Propensity Score-Matched Study

BACKGROUND

Early mobilization has been shown to promote functional recovery and prevent complications in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, the efficacy of early mobilization in patients with aSAH remains unclear. This study aimed to investigate the association between early mobilization and functional outcomes in patients with aSAH.

METHODS

This multicenter retrospective study was conducted in Japan and included patients with aSAH who received physical therapy with or without occupational therapy from April 2014 to March 2019. The primary outcome was the modified Rankin Scale (mRS) score, with a favorable functional outcome defined as an mRS score of 0-2 and an unfavorable outcome with an mRS score of 3-5. Patients initiating walking training within 14 days of aSAH onset were classified into the early mobilization group, whereas those initiating training after 14 days were classified into the delayed mobilization group. Propensity score matching analysis was performed to assess the association between early mobilization and favorable outcomes.

RESULTS

A total of 718 patients were screened, and 450 eligible patients were identified. Before matching, 229 patients (50.9%) were in the early mobilization group and 221 (49.1%) were in the delayed mobilization group. After matching, each group consisted of 122 patients, and the early mobilization group exhibited a higher proportion of favorable outcomes than did the delayed mobilization group (81.1% vs. 52.5%, risk difference 28.7%, 95% confidence interval 17.4-39.9, p < 0.001).

CONCLUSIONS

This multicenter retrospective study suggests that initiating walking training within 14 days of aSAH onset is associated with favorable outcomes.

Motor Imagery and Frontal Head Oxygenation: An fNIRS Study

Motor imagery (MI) is a manifestation of mental movements, but it cannot be identified visually. Therefore, to a large extent, MI assessment has not yet been established. The present study aimed to investigate whether frontal oxy-Hb changes and cardiac autonomic nervous system activity during MI are associated with the psychometric scale assessment of MI and clarify the utility of each index in MI assessment. Thirty-one healthy men and women were included in this study, and Pocket NIRS Duo was used to assess frontal oxygenated hemoglobin levels during walking MI. Simultaneously, heart rate and sympathetic index (low and high frequency (LF/HF) during MI were evaluated using Chiryou Meijin, a heart rate frequency analyser. In addition, a psychometric scale evaluation was carried out in MC and VAS, and its correlation with oxy-Hb levels, heart rate (HR), and LF/HF was investigated. HRs and LF/HF during MI were significantly increased compared with those at rest. However, oxy-Hb levels during MI were not increased. There was a significant correlation between right oxy-Hb levels and mental chronometry (MC) during MI (r = -0.3, p < 0.05). HR and LF/HF were not correlated with MC. VAS was not correlated with oxy-Hb levels, HR, or LF/HF. The results of this study confirm an association between MI performance and frontal oxy-Hb changes and that brain activity is not necessarily elevated during MI. HR were significantly increased but did not show any association with MC.

Changes in Prefrontal Cortical Oxygenation During Tilt Table Orthostatic Hypotension in Subarachnoid Haemorrhage Patients

Cerebral vasospasm and delayed cerebral ischaemia in patients with subarachnoid haemorrhage (SAH) are more likely to occur within the first two weeks of bleeding. Thus, conventional management involves absolute rest for two weeks. Recently, studies have reported on the possibility of early mobilisation after SAH; however, its safety has not been sufficiently evaluated. The present study investigates the relationship between cerebral cortex oxygenation and orthostatic hypotension in SAH patients using near-infrared spectroscopy (NIRS). Four SAH patients were laid supine for 5 min before performing a head-up tilt (HUT) to 30°, 45°, and 60° every 5 min using a tilt table bed. Arterial blood pressure was measured before and immediately after HUT. We evaluated O2Hb levels of the left and right prefrontal cortex (PFC) in 11 of 12 times that could be performed without stopping due to orthostatic hypotension. We analysed O2Hb levels at up to 60 s at 10-s intervals after HUT 60 s before mobilisation. We found that O2Hb levels decreased after the first (30°) HUT, but increased after HUT at 45° and 60°. Over a 60-s period, no statistically significant difference was observed. Arterial blood pressure fell by 6% on average across all the 12 tests. These results reveal that HUT orthostatic arterial hypotension caused an instantaneous decrease in oxygenation, but it returned to the baseline shortly thereafter. It is important to monitor the degree of orthostatic hypotension in patients after SAH. Gradual mobilisation may minimise the decrease in arterial blood pressure and maintain oxygenation of the cerebral cortex.

Mechanism and Function of the Catch State in Molluscan Smooth Muscle: A Historical Perspective

Molluscan smooth muscles exhibit the catch state, in which both tension and resistance to stretch are maintained with very low rates of energy consumption. The catch state is studied mainly on the anterior byssus retractor muscle (ABRM) of a bivalve molluscan animal, Mytilus, which can easily be split into small bundles consisting of parallel fibers. The ABRM contracts actively with an increase in the intracellular free Ca ion concentration, [Ca²⁺]i, as with all other types of muscle. Meanwhile, the catch state is established after the reduction of [Ca²⁺]i to the resting level. Despite extensive studies, the mechanism underlying the catch state is not yet fully understood. This article briefly deals with (1) anatomical and ultrastructural aspects of the ABRM, (2) mechanical studies on the transition from the active to the catch state in the isotonic condition, (3) electron microscopic and histochemical studies on the intracellular translocation of Ca ions during the transition from the active to the catch state, and (4) biochemical studies on the catch state, with special reference to a high molecular mass protein, twitchin, which is known to occur in molluscan catch muscles.

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.

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-β treatment in patients with multiple sclerosis is associated with transient increase in serum IL-6 level in response to interferon-β 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.

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.

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.

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.

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 η and Pol κ across 1,N 6-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.

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.

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.

Mutagenesis induced by a single 1,N6-ethenodeoxyadenosine adduct in human cells

To study the genotoxic properties of 1,N6-ethenodeoxyadenosine (epsilondA) in human cells, a novel site-specific mutagenesis approach was developed, in which a single DNA adduct was uniquely placed in either strand of a shuttle plasmid vector. The analysis of progeny plasmid derived from the modified strand shows that epsilondA, when incorporated into the position of the second A of 5'-CAA (codon 61 of the ras gene), is mutagenic in human cells, inducing A-->T, A-->G, and A-->C mutations. The efficient induction of A-->T transversions in experiments using modified double- and singlestranded DNA substrates supports the hypothesis that A:T-->T:A transversions in human and animal tumors induced by vinyl compounds reflect misinsertion of dAMP opposite this adduct. Mutagenic events were similar when the adduct was incorporated into either the leading or the lagging strand. EpsilondA was more mutagenic than 8-oxodeoxyguanosine, which induced targeted G-->T transversions in HeLa cells. In Escherichia coli, epsilondA did not significantly miscode (<0.27%) even in the presence of induced SOS functions.

Ultrastructure and 18S rDNA sequence analysis of Wobblia lunata gen. et sp. nov., a new heterotrophic flagellate (Stramenopiles, Incertae sedis)

A new heterotrophic flagellate Wobblia lunata gen. et sp. nov. is described. This organism usually attaches to the substratum showing a wobbling motion, and sometimes glides on the substratum or swims freely in the medium. W. lunata has various features characteristic of the stramenopiles. These include a hairy flagellum with tripartite tubular hairs, a mitochondrion with tubular cristae, arrangement of flagellar apparatus components and a double helix in the flagellar transition zone. W. lunata shares a double helix with heterotrophic stramenopiles, including Developayella elegans, oomycetes, hyphochytrids, opalinids and proteromonads, and could be placed in the phylum Bigyra Cavalier-Smith. However, from 18S rDNA tree analysis, these organisms form two distantly-related clades in the stramenopiles, and Wobblia appears at the base of the stramenopiles. Evaluation of morphological features and comparison of 18S rDNA sequences indicate that W. lunata is a member of the stramenopiles, but it is distinct from any other stramenopiles so far described. Its phylogenetic position within the stramenopiles is uncertain and therefore W. lunata is described as a stramenopile incertae sedis.

Cellular response to exocyclic DNA adducts

The mutagenic potential of three exocyclic DNA adducts was studied in Escherichia coli and simian kidney cells by incorporating them into single-stranded DNA. Differences in the mutagenic potency of the adducts were observed between hosts: 1,N6-ethenodeoxyadenosine and 3,N4-ethenodeoxycytidine were more mutagenic in simian cells, whereas 1,N2-(1,3-propan-1,3-diyl)-2'-deoxyguanosine was more mutagenic in E. coli. To investigate the cellular response to DNA adducts, a double-stranded DNA vector system was developed. Use of this system showed that 1,N6-ethenodeoxyadenosine blocks DNA synthesis strongly, and DNA synthesis past this adduct was highly accurate in E. coli. The blockage of DNA synthesis was overcome in an error-free manner by the recombination repair mechanism (daughter-strand gap repair).

[A patient presented with atypical paroxysmal kinesigenic choreoathetosis and Becker muscular dystrophy]

A 22-year-old man had choreatic movements in upper limbs, neck and trunk for over twelve years which were associated with dystonia in lower limbs upon initiating voluntary movements. The choreatic movement lasted for a few seconds and the dystonia lasted for a few minutes. He also had high serum CK levels and hypertrophic calf muscles. His muscle strength and deep tendon reflexes were normal. His choreatic movements fulfill the criteria for paroxysmal kinesigenic choreoathetosis (PKC). However, it was unclear what the symptom of dystonia was due to. From a muscle biopsy and DNA analysis, he was diagnosed as having Becker muscular dystrophy. Administration of anticonvulsant improved the dystonia as well as the choreatic movement, which showed that the dystonia was a symptom of PKC. Coincidence of choreatic movements and dystonias which had different lasting time in a patient of PKC was atypical and had not previously reported.

Is the growth of brown adipocytes necessary for cold acclimation in mice?

Chronic exposure to cold increases the growth of brown adipose tissue and the resistance to more severe cold, thus improving thermogenesis. The present study examined the possibility that dietary compounds can modify cold acclimation. Adenosine (ADO) or adenine (ADE) were administered in drinking water (0.05%, w/v) for 5 weeks to male ddY strain mice from 4 weeks of age. At 5 weeks of age, the mice were exposed to 4 degrees C for 4 weeks. After termination of this period, the interscapular brown adipose tissue (IBAT) and rectal temperature on acute exposure to severe cold (-20 degrees C) for 60 min were measured. Chronic exposure to cold increased the weight of IBAT and made mice resistant to a fall in rectal temperature on exposure to severe cold. The growth of IBAT and improvement in thermogenesis can be used as a cold acclimation profile in ddY mice. The growth of IBAT was selectively prevented by ingestion of ADO. The improvement in thermogenesis was reduced, but only a little, by the ingestion of either ADO or ADE. Thus, growth of brown adipocytes might not be necessary for cold acclimation in mice.

Thermoregulatory responses of the inbred heat-tolerant FOK rat to cold

The responses of inbred heat-tolerant FOK rats to cold were compared with those of Wistar King A/H (WKAH) and Std:Wistar (WSTR) strains. The fall of colonic temperature during cold exposure was unexpectedly smaller in FOK than in other groups, but the onset of shivering was delayed in FOK. Norepinephrine (NE)-induced in vivo oxygen consumption and the mitochondrial uncoupling protein 1 level of brown adipose tissue (BAT) were not different among the groups, but the cold-induced increases in in vivo oxygen consumption as well as plasma glycerol and free fatty acids were higher in FOK than in other groups. In vitro NE-induced oxygen consumption of BAT was less in FOK than WSTR, but not WKAH. The magnitude of the NE-induced increase in blood flow through BAT was higher in FOK than in other groups. These results suggest that FOK paradoxically have a high capacity for nonshivering thermogenesis in spite of their high capacity for heat tolerance, probably due to an increased lipid utilization and improved circulation of BAT.

An inverse correlation between serum leptin levels and hemoglobin A1c in patients with non-insulin dependent diabetes mellitus

We measured serum leptin concentrations in 70 patients with diabetes mellitus to investigate the relationship between serum leptin levels and glycemic control. A positive correlation between serum leptin levels and body mass index or plasma insulin was obtained as reported previously. The present study also demonstrated an inverse association of serum leptin levels with hemoglobin A1c (HbA1c). Multiple regression analysis revealed that HbA1c was an independent determinant of serum leptin levels. These results suggest that HbA1c may be a factor to influence serum leptin levels and that hyperglycemia for a long period or poorly controlled diabetes may reduce leptin levels.

Cerebellar microfolia and other abnormalities of neuronal growth, migration, and lamination in the Pit1dw-J homozygote mutant mouse

The Snell dwarf mouse (Pit1dw-J homozygote) has a mutation in the Pit1 gene that prevents the normal formation of the anterior pituitary. In neonates and adults there is almost complete absence of growth hormone (GH), prolactin (PRL), thyroxin (T4), and thyroid-stimulating hormone (TSH). Since these hormones have been suggested to play a role in normal development of the central nervous system (CNS), we have investigated the effects of the Pit1dw-J mutation on the cerebellum and hippocampal formation. In the cerebellum, there were abnormalities of both foliation and lamination. The major foliation anomalies were 1) changes in the relative size of specific folia and also the proportional sizes of the anterior vs posterior cerebellum; and 2) the presence of between one and three microfolia per half cerebellum. The microfolia were all in the medial portion of the hemisphere in the caudal part of the cerebellum. Each microfolium was just rostral to a normal fissure and interposed between the fissure and a normal gyrus. Lamination abnormalities included an increase in the number of single ectopic granule cells in the molecular layer in both cerebellar vermis (86%) and hemisphere (40%) in comparison with the wild-type mouse. In the hippocampus of the Pit1dw-J homozygote mouse, the number of pyramidal cells was decreased, although the width of the pyramidal cell layer throughout areas CA1-CA3 appeared to be normal, but less densely populated than in the wild-type mouse. Moreover, the number of granule cells that form the granule cell layer was decreased from the wild-type mouse and some ectopic granule cells (occurring both as single cells and as small clusters) were observed in the innermost portion of the molecular layer. The abnormalities observed in the Pit1dw-J homozygote mouse seem to be caused by both direct and indirect effects of the deficiency of TSH (or T4), PRL, or GH rather than by a direct effect of the deletion of Pit1.

Quantitative analysis of edema in the dorsal nerve roots induced by acute mechanical compression

STUDY DESIGN

Edema in the dorsal nerve roots caused by acute compression was assessed quantitatively in the lumbar spine of the adult dog.

OBJECTIVE

To establish quantitative evaluation of edema in the dorsal nerve roots and to observe changes after acute compression with time.

SUMMARY OF BACKGROUND DATA

Mechanical compression induces an increase in microvascular permeability of the endoneurial capillaries and results in intraneural edema. However, there are no quantitative studies on edema in the nerve roots.

METHODS

The seventh lumbar nerve root was compressed with a 60-g force clip for 10 minutes. The nerve roots were removed immediately and at 24 hours, 1 week, and 3 weeks after compression. Nerve roots from the control and the sham groups were also obtained. Before removing the nerve roots, Evans blue albumin was injected intravenously. Changes in edema were examined using fluorescence microscopy. Evans blue albumin emits a bright red fluorescence. The relative red fluorescent area was calculated using computer image analysis, and the data were used to indicate the degree of edema.

RESULTS

In the compressed segment, edema was most pronounced just after decompression and reduced in nerves removed at 24 hours. In nerves removed at 1 week, edema was pronounced but was reduced at 3 weeks. In the segments closest to the spinal cord, edema was seen after 1 week and was significant after 3 weeks. In the segments closest to the dorsal root ganglion, edema was not detected at any time.

CONCLUSION

In the dorsal nerve roots the degree and the area of edema changed with time elapsed after acute compression. The degree of edema 24 hours after decompression was one third the degree immediately after decompression. These results show that edema induced by mechanical compression can recover after decompression.

Mutagenic potential of stereoisomeric bay region (+)- and (-)-cis-anti-benzo[a]pyrene diol epoxide-N2-2'-deoxyguanosine adducts in Escherichia coli and simian kidney cells

We have investigated the mutagenic potential of site-specifically positioned DNA adducts with (+)- and (-)-cis-anti stereochemistry derived from the binding of r7,t8-dihydroxy-t9,10-epoxy-7,8,9, 10-tetrahydrobenzo[a]pyrene (BPDE) to N2-2'-deoxyguanosine (G1 or G2) in the sequence context 5'TCCTCCTG1 G2CCTCTC. BPDE-modified oligodeoxynucleotides were ligated to a single-stranded DNA vector and replicated in Escherichia coli or simian kidney (COS7) cells. The presence of (+)- or (-)-cis adduct strongly reduced the yield of transformants in E. coli, and the yield was improved by the induction of SOS functions. Both adducts were mutagenic in E. coli and COS cells, generating primarily G --> T transversions. In E. coli, the (-)-cis adduct was more mutagenic than the (+)-cis adduct, while in COS cells, both adducts were equally mutagenic. These results were compared with those obtained with stereoisomeric (+)- and (-)-trans adducts [Moriya, M., et al. (1996) Biochemistry 35, 16646-16651). In E. coli, cis adducts, especially (-)-cis adducts, are consistently more mutagenic than the comparable trans adduct. In COS cells, trans adducts yield higher frequencies of mutations than the two cis adducts and, with the exception of the high-mutation frequency associated with the (+)-trans adduct at G2, relatively small differences in mutation frequencies are observed for the three other adducts. In E. coli, mutation frequency is a pronounced function of adduct stereochemistry and adduct position. These findings suggest that the fidelity of translesional synthesis across BPDE-dG adducts is strongly influenced by adduct stereochemistry, nucleotide sequence context, and the DNA replication complex.

Novel dithiocarbamate carbapenems with anti-MRSA activity

A new series of 1beta-methyl carbapenems, in which a disubstituted-aminothiocarbonylthio moiety was attached to the C-2 position of the carbapenem nucleus, were prepared and evaluated for anti-MRSA activity. These derivatives showed good in vitro antibacterial activity against high-level MRSA, and the finding of good affinity for PBP-2' supported these results. Some of the compounds having favorable protein-binding affinity showed excellent in vivo anti-MRSA activity.

Spontaneous rupture of the uterus caused by placenta percreta at 28 weeks of gestation: a case report

Placenta percreta is a rare complication of pregnancy. Rupture of the uterus due to placenta percreta is one of the most urgent obstetrical catastrophes. Recently, we observed a patient who developed placenta percreta accompanied by spontaneous uterine rupture at 28 weeks of gestation. A 29-year old gravida 3, para 1, who had a history of one cesarean section and one miscarriage with dilatation and curetage, was seen at 28 weeks of gestation. An acute abdomen and shock were diagnosed. Immediate laparotomy revealed a transverse rupture on the fundus of the uterus. A hysterectomy was performed. Pathological examination of the uterus showed placenta percreta. Rupture of the uterus due to placenta percreta before the onset of labor is extremely rare.

Auditory projections from the IC to the SCN by way of the LG in the mole, Mogera

To study morphological substrates for sensory specialization in subterranean mammals, we investigated both auditory and visual pathways in the mole. The inferior colliculus (IC), an auditory relay, projects not only to the medial geniculate, the major gateway to the auditory cortex, but also to the lateral geniculate (LG), the major gateway to visual cortex. Further evidence is that the LG does not send many fibers to the cortex in the mole. Instead, the auditory inputs to the LG are likely to be conveyed to the suprachiasmatic hypothalamic nucleus (SCN), which plays a role in photoperiodic functions in common mammals. Auditory inputs to the SCN may subserve periodic reproductive behaviors in the exclusively separated territorial domains of subterranean mammals.

[Effects of phenylalanine and tyrosine on cold acclimation in mice]

The effects of phenylalanine (PHE) and tyrosine (TYR) on cold acclimation were studied in mice of the ddY strain. At 5 weeks of age, mice were maintained at 4 degrees C for 4 weeks. Test groups of mice were supplied with a 0.05% (w/v) solution of PHE or TYR as drinking water in addition to water. We measured changes in body weight, intake of water and food, rectal temperature upon acute exposure to -20 degrees C, weight of interscapular brown adipose tissue (BAT) and the levels of glucose, nonesterified fatty acids (NEFA) and 3H-butyrate in the blood prior to and after exposure to the lower temperature of -20 degrees C. Chronic exposure to cold (4 degrees C) reduced body-weight gain for the first two weeks but weight gain recovered within the next two weeks. PHE and TYR partially inhibited the gain in body weight under exposing to cold. TYR reduced the gain of body weight under room temperature. Exposure to cold stimulated the daily consumption of food. Both PHE and TYR somewhat enhanced the food intake when exposed to cold. Exposure to cold rendered mice resistant to severe cold (-20 degrees C). Both PHE and TYR did not reduce this resistance except in the early state in the case of TYR. Exposure to cold increased the weight of BAT but both PHE and TYR prevented this increase. The effect of TYR was determined in the case fed under room temperature. Cold exposure changed the utilization of glucose, NEFA and 3H-butyrate in the blood when exposed to severe cold (-20 degrees C). Both PHE and TYR prevented the change in NEFA. It remains to be confirmed whether the growth of brown adipocytes is always necessary when mice acclimate to cold.

[Effects of adenosine and adenine on cold acclimation in mice]

The effects of adenosine (ADO) and adenine (ADE) on cold acclimation were studied in mice of the ddY strain. At 5 weeks of age, mice were maintained at 4 degrees C for 4 weeks. Test groups of mice were supplied with a 0.05% (w/v) solution of ADO or ADE as drinking water in addition to water. We measured changes in body weight, intake of water and food, rectal temperature upon acute exposure to -20 degrees C, weight of interscapular brown adipose tissue (BAT) and the levels of glucose, nonesterified fatty acids (NEFA) and 3H-butyrate in the blood prior to and after exposure to the lower temperature of -20 degrees C. Chronic exposure to cold (4 degrees C) reduced body-weight gain for the first two weeks but weight gain recovered within the next two weeks. ADO partially but selectively inhibited the gain in body weight. This effect was marked in mice maintained at room temperature. Such an inhibitory effect was the case of ADE in the room temperature. Exposure to cold stimulated the daily consumption of food. ADO further and selectively enhanced food intake, but ADE enhanced that in room temperature. Cold increased in daily intake of water. Both ADO and ADE accelerated the intake of water. This effect was marked in mice maintained at 4 degrees C and the effect of ADE was considerable. Mice chose to drink the water that contained ADO, while the choice of water that contained ADE was apparent only during exposure to cold. Exposure to cold rendered mice resistant to severe cold (-20 degrees C). ADO and ADE partially reduced this resistance. Exposure to cold increased the weight of BAT but ADO selectively prevented this increase. Cold did not change the levels of the various compounds measured in the blood. In mice exposed to 4 degrees C for 4 weeks, acute exposure to severe cold decreased the glucose level and increased the levels of NEFA and 3H-butyrate. ADO selectively prevented the changes in the levels of NEFA and 3H-butyrate. It remains to be confirmed whether the growth of brown adipocytes is always necessary when mice acclimate to cold.

New xenograft model of multiple myeloma and efficacy of a humanized antibody against human interleukin-6 receptor

A new xenograft model of multiple myeloma (MM), where growth is strongly regulated by interleukin-6 (IL-6), was established in severe combined immunodeficiency (SCID) mice. In this model, endogenous IL-6 from SCID mice was ineffective at eliciting growth of the established human MM cell line KPMM2; these cells achieved autonomous growth through their autocrine secretion of IL-6. The etiopathology in this disease model is consistent with that of human MM. When greater than 3 x 10(6) KPMM2 cells were injected intravenously (IV), tumors developed in all mice and were predominantly localized in their bone marrow. Tumors were also apparent in the lymph nodes, but absent from other organs. Immunostaining of cell surface antigen (CD38) showed that more than 40% of bone marrow cells in femur were of myeloma origin in the advanced stage of tumor progression (day 37). Histologic analysis of these mice show that bone marrow was largely occupied by plasmablastic cells and bones had developed osteolytic lesions at multiple sites. Concurrently, there was a decrease in bone density throughout the body and a significant increase in ionized plasma calcium. M-protein was detected in the serum within 10 days after transplantation, which correlated with the tumor progression. Between 30 and 40 days after the transplantation, mice presented with a rapid and severe loss of body weight, hind leg paralysis, and fatigue. Subsequently, the mice died within a week. A single IV injection of 0.2 mg humanized anti-IL-6 receptor antibody (hPM1) into mice on the day after tumor transplantation substantially suppressed the elevation of serum M-protein and development of the tumor-associated abnormalities and significantly increased in the life span of tumor-bearing mice. Our data show the usefulness of this model to analyze the pathologic role of IL-6 in MM and the efficacy of targeting the IL-6 receptor in IL-6-dependent KPMM2 cells.

Fidelity of translesional synthesis past benzo[a]pyrene diol epoxide-2'-deoxyguanosine DNA adducts: marked effects of host cell, sequence context, and chirality

We have used a site-specific approach to investigate the mutagenic potential of (+)- and (-)-trans-anti-benzo[a]pyrene diol epoxide (BPDE) DNA adducts. Oligodeoxyribonucleotides (5'TCCTCCTG1G2-CCTCTC), modified at the exocyclic amino groups of G1 or G2, were incorporated into a single-stranded shuttle vector and introduced into Escherichia coli or simian kidney (COS) cells. This experimental system permits translesional synthesis to proceed in the absence of DNA repair. The presence of (+)- or (-)-BPDE-N2-dG adducts strongly inhibited translesional synthesis in E. coli; induction of cellular SOS functions reduced this blocking effect. Vectors containing (+)-BPDE adducts at G1 or G2 generated mutation frequencies of 19% and 3%, respectively; these values were not altered significantly by induction of SOS functions. In COS cells, (+)-BPDE-modified vectors generated mutation frequencies of 13% at G1 and 45% at G2. In E. coli, the (-)-BPDE adduct generated mutation frequencies of < or = 2% at G1 and G2 and, in COS cells, 13% at G1 and 21% at G2. The predominant mutations in E. coli and COS cells were G-->T transversions targeted to the site of the lesion; however, when G2 was modified, a significant number of targeted G-->A and G-->C mutations were observed in COS cells. We conclude from this study that (+)-and (-)-BPDE-N2-dG adducts pair preferentially to dCMP and dAMP during translesional synthesis in a process that is strongly influenced by the stereochemistry of the adduct, by the bases flanking the lesion, and by host cell factors.