Chronic Neck Pain Prevalence Before and After COVID-19 Restrictions and Its Relationship With Digital Device Screen Viewing: A Population Study

OBJECTIVE

To estimate the prevalence of chronic neck pain (CNP) among the adult population in Peru during the post-coronavirus disease 2019 (COVID-19) restriction period compared with that during the pre-pandemic period and evaluate its association with prolonged digital devices connected to the internet (DDCI) screen viewing.

METHODS

We conducted a cross-sectional study using a representative sample of adults living in Peru in November 2022. A structured survey was employed to identify CNP, and the exposure variable was set as the duration of DDCI screen viewing. The McNemar test was used to compare CNP prevalence pre- and post-COVID-19 restrictions, and ordinal logistic regression was used to evaluate its association with prolonged screen viewing.

RESULTS

A total of 1,202 individuals participated, with 52.8% females and 79.9% residing in urban areas. Following the restrictions, the prevalence of CNP occurring daily or almost daily and at least once a week was 14.8% and 27.8%, respectively (95% confidence Interval [95% CI], 12.6-17.3 and 24.9-30.9), representing a significant increase (p<0.001) compared with pre-pandemic estimates. Notably, among those viewing DDCI screens for ≥8 hours, the odds ratio for CNP frequency escalation compared with those who did not or rarely view screens was 1.61 (95% CI, 1.04-2.50; p=0.033).

CONCLUSION

Approximately 4 of 10 adults in Peru experienced CNP following the lifting of COVID-19 social restrictions, more than double the pre-pandemic prevalence. Furthermore, prolonged viewing of DDCI screens increased the risk of having this condition.

Functional engineered heart tissue cultured in a rotating wall vessel bioreactor improve cardiac function in the distressed rat heart

Introduction

How to construct massive cardiac tissue and culture it with functional improvement may be crucial as cardiomyogenesis in failed heart. We previously presented that dynamic culture in a rotating wall vessel (RWV) bioreactor could provide a better culture environment for maintenance of the engineered 3D cardiac tissue. However, it is unknown about the effect of the tissue cultured in a RWV bioreactor on engraftment and improvement of function in the distressed rat heart.

Hypothesis

We hypothesized that the engineered 3D cardiac tissue cultured in a RWV bioreactor could improve its engraftment and lead recovery of cardiac function in rat infarction model.

Methods

We made engineered cardiac tissue by seeding 2.0 × 106 human induced pluripotent stem cell derived cardiomyocytes on the PLGA fiber sheet. It was cultured in the RWV bioreactor for seven days (RWV group). For the control, static culture has been done. After in vitro assessment, these tissues were transplanted to myocardial infarction model nude rats (sham, control, and RWV group, n=10, respectively) and cardiac performance was evaluated by ultrasonography. Four weeks after transplantation, we evaluated their hearts by histological analysis.

Results

The RWV group demonstrated maturation of cardiomyocytes evidenced by significantly higher expression of Troponin T (TnT), sarcomeric α actinin (SAA), connexin 43 (Cx43) and myosin heavy chain 7 (MYH7) than the control by Western blots (TnT; 2.7±1.0 vs. 1.0±0.4, p&lt;0.01, SAA; 2.1±0.7 vs. 1.0±0.2, p&lt;0.01, Cx 43; 2.0±0.6 vs. 1.0±0.1, p&lt;0.05, MYH7; 10.9±2.7 vs. 1.0±0.1, p&lt;0.01). In the culture supernatant, the concentration of cytokines related to angiogenesis was significantly higher in the RWV group than in the control (VEGF; 29.6±7.4 vs. 12.2±4.3pg/ml, p&lt;0.01, HGF; 72.7±9.9 vs. 42.6±5.9pg/ml, p&lt;0.01). Four weeks after transplantation, the left ventricular ejection fraction was significantly improved in the RWV group than in the control (RWV vs. control; 47±4.9 vs. 38±6.9%, p&lt;0.01). On histological analysis, more engineered cardiac tissue survived in the RWV group than in the control (RWV vs. control; 7/10 vs. 3/10, p=0.18). A vascular-like structure double-stained with isolectin B4 and smooth muscle actin was partially observed in the transplanted tissue. LV remodeling exhibiting extracellular collagen deposition (fibrotic area, RWV vs. control; 17±4.3 vs. 24±5.2%, p&lt;0.05) and cardiomyocyte hypertrophy (RWV vs. control; 16±1.7 vs. 18±2.1μm, p&lt;0.05) was significantly attenuated in RWV group than in the control. Neovascularization was significantly noted in the RWV group compared with the control (capillary density, RWV vs. control; 545±113 vs. 356±92, p&lt;0.01).

Conclusion

Functional engineered 3D cardiac tissue cultured in a RWV bioreactor could induce angiogenesis and improved its engraftment, leading significant improvement of cardiac function in rat infarction model.

Dynamic culture in a RWV bioreactor

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science

The genetic basis of speciation in the Giliopsis lineage of Ipomopsis (Polemoniaceae)

One of the most powerful drivers of speciation in plants is pollinator-mediated disruptive selection, which leads to the divergence of floral traits adapted to the morphology and behavior of different pollinators. Despite the widespread importance of this speciation mechanism, its genetic basis has been explored in only a few groups. Here, we characterize the genetic basis of pollinator-mediated divergence of two species in genus Ipomopsis, I. guttata and I. tenuifolia, using quantitative trait locus (QTL) analyses of floral traits and other variable phenotypes. We detected one to six QTLs per trait, with each QTL generally explaining small to modest amounts of the phenotypic variance of a backcross hybrid population. In contrast, flowering time and anthocyanin abundance (a metric of color variation) were controlled by a few QTLs of relatively large effect. QTLs were strongly clustered within linkage groups, with 26 of 37 QTLs localized to six marker-interval 'hotspots,' all of which harbored pleiotropic QTLs. In contrast to other studies that have examined the genetic basis of pollinator shifts, our results indicate that, in general, mutations of small to modest effect on phenotype were involved. Thus, the evolutionary transition between the distinct pollination modes of I. guttata and I. tenuifolia likely proceeded incrementally, rather than saltationally.

Down-scattered neutron imaging detector for areal density measurement of inertial confinement fusion

A custom developed (6)Li glass scintillator (APLF80+3Pr) for down-scattered neutron diagnostics in inertial confinement fusion experiments is presented. (6)Li provides an enhanced sensitivity for down-scattered neutrons in DD fusion and its experimentally observed 5-6 ns response time fulfills the requirement for down-scattered neutron detectors. A time-of-flight detector operating in the current mode using the APLF80+3Pr was designed and its feasibility observing down-scattered neutrons was demonstrated. Furthermore, a prototype design for a down-scattered neutron imaging detector was also demonstrated. This material promises viability as a future down-scattered neutron detector for the National Ignition Facility.

Haplotype-based case-control study of receptor (calcitonin) activity-modifying protein-1 gene in cerebral infarction

Calcitonin gene-related peptide (CGRP) receptor is a complex molecule that consists of calcitonin receptor-like receptor and receptor activity-modifying protein-1 (RAMP1). It was recently reported that RAMP1-deficient mice (RAMP1(-/-)) showed inflammatory responses with a transiently significant increase in serum CGRP levels and proinflammatory cytokines when compared with RAMP1(+/+) mice. The aim of this study was to investigate the relationship between the human RAMP1 gene and cerebral infarction (CI) using single-nucleotide polymorphisms (SNPs) in a Japanese population. We selected six SNPs in the human RAMP1 gene (rs3754701, rs3769048, rs7557078, rs1584243, rs10199956 and rs7590387) and performed a case-control study using each SNP and haplotype in 171 CI patients and 234 controls. There were no significant differences in overall distribution of genotype and allele frequencies of the SNPs between the CI and control groups. However, there was a significant difference in overall distribution between the CI and control groups (P<0.001) in the haplotype-based case-control study with the combinations of rs3754701-rs3769048-rs7590387. The T-A-C susceptibility haplotype for CI was significantly more frequent than in the control group (P=0.0024). The results suggest that the T-A-C haplotype is a genetic marker for CI, and that RAMP1 or neighbouring genes are associated with increased susceptibility to CI.

Tacrolimus and methotrexate for the prophylaxis of graft-versus-host disease after unrelated donor cord blood transplantation for adult patients with hematologic malignancies

Eighteen patients with hematologic malignancies underwent cord blood transplantation (CBT) from unrelated donors after being conditioned with myeloablative or reduced-intensity regimens, and received tacrolimus and methotrexate (15 mg/m(2) on day 1, 10 mg/m(2) on days 3 and 6) as graft-versus-host disease (GVHD) prophylaxis. The median number of nucleated cells in infused cord blood was 2.66 x 10(7)/kg (range 1.90 to 4.15 x 10(7)/kg). Engraftment was achieved in 16 of 18 patients. The median time to absolute neutrophil count >0.5 x 10(9)/L was 21.5 days (range 17 to 32), and the median time to platelet count >2.0 x 10(9)/L was 36 days (range 26 to 57). Of the 16 evaluable patients, five and eight had grades I and II acute GVHD, respectively, and none had grades III/IV acute GVHD. The cumulative incidence of grade II acute GVHD was 44.4%. Chronic GVHD occurred in 7 of 15 evaluable patients: limited type in three patients, extensive type in four patients. Of the 18 patients, 14 were alive and disease-free between 173 and 1514 days after CBT (median 746 days). The probability of disease-free survival at 2 years was 79.1%. These results, although in a retrospective study, suggested that tacrolimus and short-term methotrexate effectively prevented the occurrence of severe acute GVHD after unrelated CBT, and may contribute to a high survival rate.

Sperm protein 17 influences the tissue-specific malignancy of clear cell adenocarcinoma in human epithelial ovarian cancer

Clear cell adenocarcinoma of the ovary has a poor prognosis due to chemoresistance and early metastasis to the lymph nodes. It also can result in endometriosis and is the second most frequent type of ovarian cancer in Japan. Serous adenocarcinoma of the ovary is another common epithelial cancer tissue subtype in Japan, and it is highly sensitive to chemotherapy. In the current study, we examined the differential expression of genes in these types of ovarian cancer and tried to analyze their functions, especially as they relate to chemoresistance. We used differential display to compare clear cell carcinoma and serous adenocarcinoma of the ovary. We identified sperm protein 17 (SP17) as a candidate gene related to the chemoresistance of clear cell carcinoma. Its differential expression was confirmed by real-time polymerase chain reaction. Because the function of the SP17 gene in ovarian cancer is not known, we examined the effect of small interfering RNA targeting the SP17 gene on the chemoresistance and proliferation of ES-2 ovarian cancer cells to paclitaxel, currently the most effective treatment for ovarian cancer. We found that this treatment decreased the chemoresistance of these cells to paclitaxel. Our results strongly suggest that SP17 plays a role in the resistance of clear cell carcinoma to chemotherapy without influencing their ability to proliferate

Total body irradiation and granulocyte colony-stimulating factor-combined high-dose cytarabine as a conditioning regimen in allogeneic hematopoietic stem cell transplantation for advanced myelodysplastic syndrome: a single-institute experience

In this study, we retrospectively evaluated the efficacy and safety of total body irradiation (TBI) and granulocyte colony-stimulating factor (G-CSF)-combined high-dose cytarabine as a conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in patients with advanced myelodysplastic syndrome (MDS). We evaluated 22 patients with advanced MDS, including refractory anemia with excess blasts (RAEB; n=10), RAEB in transformation (n=2), acute myelogenous leukemia transformed from MDS (n=6) and chronic myelomonocytic leukemia (n=4). The conditioning regimen consisted of 12 Gy of TBI and high-dose cytarabine (3 g/m(2)) every 12 h for 4 days, and the cytarabine was combined with continuous administration of G-CSF. The stem cell sources were bone marrow or peripheral blood stem cells from human leukocyte antigen (HLA)-identical siblings (n=12) and bone marrow from HLA serologically matched unrelated donors (n=10). Three patients experienced disease relapse, two of whom died of disease progression. Of 22 patients, 16 are currently alive and disease-free. The 5-year estimated overall survival, disease-free survival, relapse and non-relapse mortality rates are 76.7, 72.2, 16.6 and 14.1%, respectively. These results suggest that G-CSF-combined high-dose cytarabine could be a promising component of the conditioning regimen of allogeneic HSCT for advanced MDS, providing a low incidence of both relapse and treatment-related mortality.

Inhibition of the mammalian target of rapamycin (mTOR) by rapamycin increases chemosensitivity of CaSki cells to paclitaxel

Paclitaxel, a potent anti-neoplastic agent, has been found to be effective against several tumours, including cervical cancer. However, the exact mechanism underlying the cytotoxic effects of pacitaxel, especially in the survival-signalling pathway, is poorly understood. The aim of this study was to investigate the molecular pathway of the cytotoxic effect of paclitaxel in human cervical cancer cell lines. Four human cervical cancer cell lines were treated for 24 h with various concentration of paclitaxel, and the sensitivity was analysed by an MTT assay. The cell cycle progression and sub-G1 population were analysed by flow cytometry. Apoptosis was further measured by DNA fragmentation and microscope examination. The protein expression was determined by Western blot analysis. Our results showed that HeLa cells demonstrated the highest sensitivity to paclitaxel, whereas CaSki cells showed the lowest. In cervical cancer cells, paclitaxel induced apoptosis through an intrinsic pathway with prior G2/M arrest. In addition, we showed that paclitaxel downregulated the phosphorylation of Akt in both HeLa and CaSki cells. Interestingly, in CaSki cells, which were more suggestive of a resistant phenotype, paclitaxel induced the activation of mTOR as a downstream target of Akt. Pre-treatment with rapamycin inhibited activation of mTOR signalling and significantly enhanced the sensitivity of CaSki cells to paclitaxel by increasing apoptotic cell death. This effect was mediated, at least partly, through caspase activation. Overall, paclitaxel exerts its anti-tumour effects on cervical cancer cells by inducing apoptosis through intrinsic pathway, and rapamycin targeted to mTOR can sensitise paclitaxel-resistant cervical cancer cells.

Dose-adjusted preemptive therapy for cytomegalovirus disease based on real-time polymerase chain reaction after allogeneic hematopoietic stem cell transplantation

We have prospectively evaluated the efficacy of real-time PCR-guided preemptive therapy for CMV diseases in allogeneic hematopoietic stem cell transplant recipients with grades II-IV acute GVHD. The dose of ganciclovir was adjusted according to the viral load determined by real-time polymerase chain reaction (PCR). On detecting CMV reactivation in the plasma, ganciclovir was initiated at a dose of 5 mg/kg body weight once daily, and the dose was increased to twice daily if viral load continued to increase after initiating ganciclovir. In 39 evaluable patients, CMV reactivation assessed by real-time PCR became positive in 30 (77%). One developed CMV gastroenteritis before PCR became positive. Thus the remaining 29 patients were treated preemptively with ganciclovir. The dose of ganciclovir was increased in 12 patients (41%) of preemptively treated patients for increasing viral load. CMV diseases were diagnosed in two patients (one gastroenteritis and one retinitis), and late CMV disease was diagnosed in one patient (gastritis). The treatment was generally well-tolerated, but three patients (10%) developed neutropenia (neutrophil count less than 1.0 x 10(9)/l). In conclusion, real-time PCR-guided preemptive therapy with decreased dose of ganciclovir is feasible and does not increase the frequency of CMV diseases if the dose is adjusted according to the viral load.

Expression and sequence analyses of p33(ING1) gene in myeloid leukemia

p33(ING1) is a novel candidate tumor suppressor gene which is involved in the regulation of apoptosis. p33(ING1) interacts with p53 signaling pathway and regulates cellular growth. It has reported that the expression of p33(ING1) mRNA was decreased in lymphoid malignancies. We thus investigated the potential involvement of p33(ING1) abnormalities in myeloid leukemias. However, the levels of p33(ING1) transcript were almost equal in 3 AML cell lines and 10 fresh AML samples. In addition, neither point mutations nor deletions in p33(ING1) gene were found in myeloid leukemias. These results suggest that p33(ING1) may not be a major candidate tumor suppressor gene in myeloid leukemias.

A quantitative extraction method for the determination of trace amounts of both butyl- and phenyltin compounds in sediments by gas chromatography-inductively coupled plasma mass spectrometry

A simple and reliable extraction method was developed for quantitative determination of both butyl- and phenyltin compounds in sediments by capillary gas chromatography combined with inductively coupled plasma mass spectrometry (GC-ICP-MS). Both types of organotin compounds were extracted quantitatively from sediment by mechanical shaking into tropolone-toluene and HCl-methanol. After phase separation and pH adjustment, these organotins were ethylated with sodium tetraethylborate. The method was evaluated by analyzing PACS-2 and NIES No. 12 sediment certified reference materials. The dibutyltin (DBT; 1.14 +/- 0.02 micrograms g-1) and tributyltin (TBT; 1.01 +/- 0.04 micrograms g-1) values observed in PACS-2 sediment closely matched the certified values (DBT, 1.09 +/- 0.15; TBT, 0.98 +/- 0.13 microgram g-1 as tin). The monobutyltin (MBT) value was higher (0.62 +/- 0.02 microgram g-1) by more than two fold over the reference value (0.3 microgram g-1 as tin). The concentrations of TBT (0.18 +/- 0.04 microgram g-1) and triphenyltin (TPhT; 0.0099 +/- 0.002 microgram g-1) in the NIES No. 12 sediment were also in good agreement with the certified and reference values of TBT (0.19 +/- 0.03 microgram g-1 as compound) and TPhT (0.008 microgram g-1 as compound), respectively. Recoveries of TBT, tripentyltin (TPeT) and TPhT from spiked sediments were satisfactory (TBT, 102 +/- 3.4%; TPrT, 96 +/- 3.4%; TPhT, 99 +/- 8.5%). The detection limits as tin were in the range 0.23-0.48 ng g-1 for a 0.5 g sample size. It is also noteworthy that clean-up of the extract is not necessary because of the superior selectivity of ICP-MS detection. The present method was successfully applied to marine sediment samples.

Effect of polishing on cyclic fatigue strength of CAD/CAM ceramics

The biaxial flexural strength and cyclic fatigue biaxial flexural strength of CAD/CAM ceramics polished with #220, 400, 600 and 1000 diamond pads were measured in an effort to determine the effect of surface roughness on fatigue behavior of dental ceramics. The surface roughness was improved after polishing with a smaller diamond grain pad. The flexural strengths of the specimens polished with #220, 400, 600 and 1000 diamond pad were 75.2, 76.6, 82.2, and 83.3 MPa, respectively; the fatigue flexural strength of those with #220, 400, 600 and 1000 were 53.0, 58.1, 60.0, and 61.5 MPa, respectively. Both the flexural and fatigue flexural strengths increased with improvement of surface profile. These results suggest the importance of polishing of dental ceramics for not only the static strength but also the cyclic fatigue strength.

Tin speciation in the femtogram range in open ocean seawater by gas chromatography/inductively coupled plasma mass spectrometry using a shield torch at normal plasma conditions

A sensitive method for the determination of ultratrace organotin species in seawater is described. The merits and demerits of derivatization methods using Grignard reagent or sodium tetraethylborate (NaBEt4) were evaluated in terms of derivatization efficiency, applicability to the programmed temperature vaporization (PTV) method, and procedural blanks. The sensitivity of the gas chromatography/inductively coupled plasma mass spectrometry (GC/ICPMS) was improved by more than 100-fold by operating the shield torch at normal plasma conditions, compared with that obtained without using it. The absolute detection limit as tin reached subfemtogram (fg) levels. Furthermore, the detection limit in terms of relative concentration was improved 100-fold by using the PTV method, which enabled the injection of a large sample volume of as much as 100 microL without loss of analyte. When the organotin species in seawater were extracted into hexane with a preconcentration factor of 1000 after ethylation with NaBEt4 and a 100 microL aliquot of the extract was injected into the GC, the instrumental detection limit in relative concentration reached 0.01 pg/L in original seawater. Sources of contamination of organotin species during the sample preparation were examined, and a purification method of NaBEt4 was developed. Finally, the method was successfully applied to open ocean seawater samples containing organotin species at the level of 1-100 pg/L.

High-speed voltammetry: dual measurement of dopamine and serotonin

A high-speed voltammetric system was designed and tested for dual measurement of dopamine (DA) and serotonin (5-HT) at 250-ms intervals. First, an anodic-cathodic square-wave pulse was delivered to activate the electrode (carbon fiber, 7 microm in diameter), then DA and 5-HT oxidation currents (current intensity) were measured when potentials were stepped from 100 to 250 mV and 300 to 450 mV, respectively. To isolate DA and 5-HT current intensities, the current observed at 100 mV was subtracted from that at 250 mV, and the current observed at 300 mV was subtracted from that at 450 mV, respectively. Measurements were performed every 250 ms. In vitro, DA and 5-HT current intensities increased with increasing concentrations of DA and 5-HT, respectively. The DA current intensity was not affected by the addition of the DA metabolite 3,4-dihydroxyphenylacetic acid (10(-6) M) or ascorbic acid (10(-5) M), but the 5-HT current intensity was affected by the addition of the 5-HT metabolite 5-hydroxyindoleacetic acid (10(-6) M) or uric acid (10(-5) M). Electrodes were used for several months without any change in sensitivity. In vivo, following intraperitoneal injection of L-DOPA to rats, an increase in striatal DA release was observed but there was no increase in release of 5-HT. Following intraperitoneal injection of 5-hydroxytryptamine there was an increase in 5-HT release but not DA release. This high-speed system was capable of obtaining stable, long-term dual measurements of DA and 5-HT in vitro and in vivo.

Pneumococcal psoas abscess

A 47-year-old woman was admitted to our hospital because of severe low back pain. A computed tomography (CT) scan revealed a left sided psoas muscle abscess. On the first hospital day, US-guided drainage was performed. Streptococcus pneumoniae was isolated from the pus. Thereafter, the open drainage of the abscess and antibiotic treatment were given with subsequent clinical improvement. Only 10 cases of pneumococcal psoas abscess have been previously reported in the world literature.

The dopamine D2 receptor antagonist sulpiride causes long-lasting serotonin release

The effects of the dopamine D2 receptor antagonist sulpiride on extracellular levels of serotonin (5-hydroxytryptamine, 5-HT) and the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA) were examined by using in vivo voltammetry. Sulpiride (1 or 3 mM, 2 microl over 24 min) was administered to freely moving rats via a cannula implanted in the striatum and 5-hydroxyindole levels were measured by using a carbon fiber voltammetry electrode implanted in the ipsilateral striatum. Six to 8 h after injection, 5-hydroxyindole levels increased 3-fold, peaked 1 to 2 days post-injection, and returned to normal levels within 2 to 4 days. These effects were suppressed by pretreatment with p-chlorophenylalanine. Two days after sulpiride injection, high-performance liquid chromatography of striatal homogenates revealed that although the 5-HT concentration was unchanged, the 5-HIAA concentration was increased significantly. These results suggest that the long-lasting elevation of 5-hydroxyindole concentrations was primarily due to increased 5-HT release.

Differential time courses of exogenous 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine and its metabolite MPP+ in the rat striatum and nucleus accumbens measured using in vivo voltammetry

The dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP) has been shown to affect nigrostriatal projection neurons to a greater extent than substantia nigra neurons that project to the nucleus accumbens. To investigate this preferential vulnerability, the intracerebral pharmacokinetics of locally-applied MPTP was investigated using in vivo voltammetry. First, we examined whether MPTP and MPP+ were measurable in vitro. At the most efficient oxidation potential for MPTP (850 mV), its metabolite MPP+ was also partly oxidized, whereas at that for MPP+ (650 mV), MPTP was not oxidized. Then, in vivo measurements were taken less than 1 mm from the site of infusion of MPTP. MPTP and endogenously produced MPP+ peaked later and took longer to return to baseline in the nucleus accumbens than in the striatum. Systemic monoamine oxidase-B inhibitor pargyline delayed the peak and return to baseline of endogenously produced MPP+ in the nucleus accumbens. Exogenously applied MPP+ also took longer to peak and return to baseline in the nucleus accumbens. These results indicate that the difference in the pharmacokinetics of exogenously applied MPTP in the striatum and nucleus accumbens may be due to a difference in uptake in these regions, and that the difference in pharmacokinetics of endogenously produced MPP+ may be due to differences in both uptake and monoamine oxidase-B activity.

Nocturnal variation in human sympathetic baroreflex sensitivity

To determine whether or not there are nocturnal variations in sympathetic baroreflex sensitivity (BRS), we measured spontaneous sympathetic BRSs in eight normal subjects (average 24.5 years old) between 2300 and 0700 h. Electrocardiogram, blood pressure, polysomnography, and muscle sympathetic nerve activity (MSA) using microneurography were recorded. We defined cardiac 'baroreflex sequences' as those that contain three or more adjacent pulses, with the systolic blood pressure and the subsequent pulse interval either continuously increased or decreased. A similar analysis was applied to sympathetic BRSs. We selected three or more adjacent pulses during which diastolic blood pressures continuously increased or decreased. Total activity in MSA was defined as burst per minute x burst amplitude and we calculated the regression coefficients between the diastolic blood pressure and the subsequent total activities in MSA. The regression coefficients were classified as either negative or positive ones. When they were less than zero, we termed them 'baroreflex sequences'. Cardiac and sympathetic BRSs were estimated from the average slope of the baroreflex sequences. Sympathetic BRS was significantly lower during sleep than while subjects were awake in the evening (P < 0.05), and it remained low after the subjects woke up in the morning (P < 0.05). Conversely, cardiac BRS had a tendency to increase during sleep in the night, but not statistically significant. This sympathetic BRS pattern may contribute to diurnal haemodynamic variables and may account, at least in part, for the connection between circadian rhythm and cardiovascular disease.

Immediate and long-term effects of 5,7-dihydroxytryptamine on rat striatal serotonergic neurons measured using in vivo voltammetry

The immediate and long-term effects of the selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) on rat striatal serotonergic neurons were examined after its intracerebroventricular administration using in vivo voltammetry. Extracellular concentration of 5-hydroxyindoles increased immediately following intracerebroventricular 5,7-DHT injection (200 microg in 24 microl, 18 min), peaked at 1.5-2 h, and returned to normal by 4 h. 5,7-DHT diffused to the contralateral striatum in detectable amounts 9 to 12 min after the start of injection and returned to basal levels by 1.5 h. Three to 6 days after 5,7-DHT lesions, 5-hydroxytryptophan administration produced an increase in striatal 5-hydroxyindoles that was greater than that produced in pre-lesioned rats. This effect was maximal at 14 to 17 days post-lesion, and remained even after 50 days. The short-term effect of 5,7-DHT may be attributable to increased serotonin release, inhibition of uptake, or monoamine oxidase inhibition. The long-term effect of 5,7-DHT lesions may attributable to increased synthesis of serotonin or decreased reuptake in remaining serotonergic neurons.

In vivo electrochemical measurement of the long-lasting release of dopamine and serotonin induced by intrastriatal kainic acid

Intrastriatal injection of the glutamate agonist kainic acid (KA) in rats has been used to produce an animal model to investigate the mechanism of acetylcholine and GABA cell death associated with Huntington's disease. In the present study, the time course of low (10(-5) M) and high (5 x 10(-3) M) concentrations of KA on striatal dopamine and serotonin release was studied in freely moving rats by using in vivo voltammetry. The response to low concentrations of KA varied between animals, either increasing dopamine release during the injection or increasing dopamine and serotonin after the injection for an extended time, suggesting that 10(-5) KA is near the threshold for KA toxicity in the striatum in rats. High concentrations of KA suppressed dopamine release during injection, with both dopamine and serotonin release increasing and remaining elevated for 1-4 and 7-21 days, respectively. KA-induced changes were inhibited by 6-cyano-7-nitroquinoxaline-2,3-dione and bicuculline increased the release of dopamine but not serotonin. These findings suggest that KA-induced changes in dopamine release resulted from a disinhibition of dopamine neurons due to KA-mediated toxicity of striatal GABA neurons. An alternate possibility is that the change in dopamine and serotonin release may have arisen from a functional modification or degeneration of presynaptic terminals.

Malignant hypertension in a patient with primary aldosteronism with elevated active renin concentration

A 40-year-old male, with a past history of hypertension but receiving no medical treatment, was referred. He manifested malignant hypertension (190/130 mmHg; Keith-Wagener III), renal dysfunction (serum creatinine, 3.8 mg/dl), and elevated plasma aldosterone (450 pg/ml) and active renin concentration (ARC, 104 pg/ml). His blood pressure was controlled with multiple antihypertensive agents and ARC thus decreased (4.3 pg/ml), but aldosterone remained elevated. Abdominal magnetic resonance imaging (MRI) revealed a right adrenal adenoma, and aldosterone-producing adenoma was confirmed by adrenal venous sampling. Primary aldosteronism very rarely develops to malignant hypertension, and even in that case ARC is suppressed. Therefore this is a rare case of primary aldosteronism complicated with malignant hypertension and high ARC.

Duration of catalepsy correlates with increased intrastriatal sulpiride

To investigate the mechanism underlying sulpiride-induced catalepsy, we simultaneously examined cataleptic behavior and the kinetics of the dopamine receptor antagonist, sulpiride of dopamine, and the dopamine metabolite 3,4-dihydroxyphenylacetic acid (DOPAC), using in vivo voltammetry. After intrastriatal administration of sulpiride to freely moving rats, the levels increased, peaked at 20 min, and remained elevated for more than 3 h. Sulpiride-induced cataleptic behavior also continued for 3 h. Levels of DOPAC peaked 180 min after the injection and did not return to baseline within the experimental period. Thus, the time-course of cataleptic behavior correlated better with elevated extracellular levels of sulpiride than with that of DOPAC. These findings suggest that sulpiride induces catalepsy via a direct action.

Comparison of gradual and rapid onset runs in a short-arm centrifugation

A gradual onset run (GOR) in a short-arm centrifugation was performed on ten healthy students. The centrifuge had a 1.8 m radius, and the subjects sat on a chair in a cabin. The Gz force increased to 2.2 Gz at 0.1 degree/sec2 for 32 min. and the same Gz-level was maintained for 20 min. Three out of ten subjects completed the whole protocol; the load on the others was terminated because of symptoms or increased heart rate. There were few symptoms such as vertigo, that was a common problem with a rapid onset run (ROR) in former experiments, due to the short-arm centrifugation. The changes of the flicker test after the load were much less in the GOR protocol than in the ROR protocol, even in the terminated group. GOR seemed preferable to ROR in preventing vertigo even though it took longer to reach the necessary G load.

[Clinical evaluation of endoscopic ultrasonography (EUS) in the diagnosis of superficial esophageal carcinoma]

Pre-operative diagnosis of the depth of invasion is important to decide the treatment of superficial esophageal carcinoma. The ability of EUS to diagnose the depth of invasion was examined in 40 lesions with superficial esophageal carcinoma between January 1993 and April 1994. The depth of invasion was classified as m1 or m2, m3 or sm1, and sm2 or more. Mucosal carcinoma could be detected clearly by using the 20MHz miniature probe. The diagnostic accuracy was 82.5% in all 40 lesions, and 77.8% in mucosal carcinoma (included with sm1). The reasons for incorrect diagnosis were broadness of the lesion, microinvasion, and artifact of endoscopic biopsy. EUS is considered to be useful even for superficial esophageal carcinoma as one of the preoperative diagnostic imagings.

[Results of annual health examination for the aged provided by the law that are predictive of increased mortality risk]

Possible risk factors associated with mortality were studied in a community using data derived from annual mass health examinations for the aged mandated by law. A total of 1,804 adults (685 men and 1,119 women) aged 40 or older in A-town, located on Tsushima Island, Nagasaki Prefecture, Japan who had participated in annual health examinations at least once between 1984 and 1990, were followed for a mean period of 4.9 years. After adjustment for age using Cox proportional hazards models, in men liver dysfunction (aspartate aminotransferase > 40 U/l or alanine aminotransferase > 35 U/l), fasting blood glucose > or = 110 mg/dl and glucosuria, and in women serum creatinine > or = 1.2 mg/dl, fasting blood glucose > or = 110 mg/dl and proteinuria were found to be associated with a significantly increased risk of total mortality. In multivariate analysis using all independent variables that were significantly associated with mortality in age-adjusted bivariate analysis, in men liver dysfunction and hyperglycemia, and in women hypercreatininemia and hyperglycemia, were significant predictors of mortality. These independent variables remained significant or marginally significant predictors of total mortality even after excluding the effects of 3 pancreatic cancer cases with liver dysfunction or hyperglycemia or 12 deaths within the first year of follow-up, being associated with at least two-fold increased hazard rate ratios. From these results, it is recommended that persons with these risk factors be followed intensively and counseled by public health personnel to modify risk factors.

Artificial G-load and chemical changes of saliva

Effectiveness of artificial G load is expected when it is used as a countermeasure against various bio-medical mishaps which are taking place in the micro-gravity environment, and probably more importantly, to prepare re-entry to the earth 1-G environment. Regarding the salivary chemical analysis, it has been known that, in case of (experimental) motion sickness, symptomatic outputs are delivered through the autonomic nervous system, and changes in salivary chemical components occur. In this study, accordingly, quantitative analyses of salivary potassium, sodium, chloride and total protein were performed before and after various levels of G loads which were produced by our short-radius human centrifuge. When the results were compared, the subjects who failed 60 minutes ride exhibited significantly higher post-load levels of potassium and sodium than those of successful 60 minutes riders. However, the differences between two groups were less clear in chloride and total protein. The result of present study indicates that salivary potassium and sodium are good indicators to represent autonomic nervous system function under the stressful condition produced by an artificial G load.

Human cardiovascular and vestibular responses in long minutes and low +Gz loading by short arm centrifuge

1.4 G, 1.7 G, and 2.0 G of +Gz and 60 minutes centrifugation was adopted to 20 healthy male subjects using 1.8 m radius centrifuge equipped to Nihon University School of Medicine. G was applied from lower G, considering G training effect for the subjects. Effects on performance decline and side effects of such a short-arm centrifugation were especially observed in the experiments, because this size of centrifuge could be used in space station in future for a strong countermeasure of cardiovascular deconditioning, demineralization from bone, etc. G training effect was observed same as higher and rapid G acceleration in fighter pilot. Subjects suffered from many types of discomfort; such as sensation of heaviness of diaphragm, cold sweat, nausea, irritable feeling, arrhythmia, tachycardia, rapid decrease of blood pressure, which sometimes caused interruption of G load. As 2.0 G and 60 minutes centrifugation seemed very tough load to the subjects, there should be necessary some G suit or other countermeasure, if we apply a higher G and/or longer G duration. Performance decline due to the load commonly continued for 1 hour or so. Side effects were observed in relation to neuro-vestibular, cardio-vascular, and autonomic nervous system.

A triangular conditioning voltage wave does not influence spontaneous neuronal activity in the rat striatum

A triangular potential wave applied shortly before each measuring triple pulse has been used in in vivo voltammetric experiments to ensure the maintenance of a high level of stability and sensitivity in the carbon fiber electrode. To investigate whether a triangular wave (0- +/- 1500 mV, 10 V/s slope) and a consecutive triple pulse affect spontaneous neuronal firing, extracellular recordings were made in the rat striatum at a distance of about 200-300 microns from the carbon fiber electrode while these potentials were being delivered. No significant change in the rate of spontaneous firing was found. A triangular pulse has proven to be very effective in lengthening the measurement lifetime of the carbon fiber electrode without interfering with the spontaneous activity of striatal neurons.

[A case report of true palmar aneurysm]

True palmar aneurysm is a rare disease of the hand. Only 12 cases of true palmar aneurysm have been reported in Japan. This occurs commonly in the hypothenar region. We experienced a 12-year-old boy who had a aneurysm of the left palmar hand successfully treated by surgery. The clinical diagnosis was established by ultra sound. Vascular reconstruction by end to end anastomosis was performed after excision of aneurysm. Pathology revealed this was true aneurysm.