Photobiomodulation of Gingival Cells Challenged with Viable Oral Microbes

The oral cavity, a unique ecosystem harboring diverse microorganisms, maintains health through a balanced microflora. Disruption may lead to disease, emphasizing the protective role of gingival epithelial cells (GECs) in preventing harm from pathogenic oral microbes. Shifting GECs' response from proinflammatory to antimicrobial could be a novel strategy for periodontitis. Photobiomodulation therapy (PBMT), a nonpharmacologic host modulatory approach, is considered an alternative to drugs. While the host cell response induced by a single type of pathogen-associated molecular patterns (PAMPs) was widely studied, this model does not address the cellular response to intact microbes that exhibit multiple PAMPs that might modulate the response. Inspired by this, we developed an in vitro model that simulates direct interactions between host cells and intact pathogens and evaluated the effect of PBMT on the response of human gingival keratinocytes (HGKs) to challenge viable oral microbes at both the cellular and molecular levels. Our data demonstrated that LED pretreatment on microbially challenged HGKs with specific continuous wavelengths (red: 615 nm; near-infrared: 880 nm) induced the production of various antimicrobial peptides, enhanced cell viability and proliferation, promoted reactive oxygen species scavenging, and down-modulated proinflammatory activity. The data also suggest a potential explanation regarding the superior efficacy of near-infrared light treatment compared with red light in enhancing antimicrobial activity and reducing cellular inflammation of HGKs. Taken together, the findings suggest that PBMT enhances the overall barrier function of gingival epithelium while minimizing inflammation-mediated breakdown of the underlying structures.

PCSK9 modulates the Wnt/beta-catenin signaling pathway in myocardial ischemia/reperfusion injury

Background

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protein that affects cholesterol homeostasis. Recent research has found that PCSK9 has various effects on the heart that are unrelated to LDL cholesterol regulation. The Wnt/β-catenin signaling pathway plays a crucial role during heart development, and it is re-activated in response to cardiac injury. Low-density lipoprotein receptor-related proteins 5 (LRP5) act as co-receptors of Wnt ligands and are indispensable for Wnt/β-catenin signal transduction. However, it is not fully elucidated whether other members of the LDLR-superfamily may be targets of PCSK9.

Purpose

This study aimed to determine if LRP5 is a PCSK9 target, study the association between PCSK9 and Wnt/β-catenin signaling, and elucidate its effect on myocardial infarction in patients with ischemic cardiomyopathy.

Methods

The expression of Lrp5, phospho-β-catenin, total β-catenin was evaluated by western blot analysis, and the effects of overexpressed PCSK9 were tested under normoxia, hypoxia, or hypoxia/re-oxygenation (H/R) in mouse cardiomyocytes (HL-1). The transcriptional activity of β-catenin was assessed using the TOP-Flash/FOP-Flash luciferase reporter assay. In addition, the impact on various downstream targets of the Wnt/β-catenin signaling pathway was assessed using a quantitative real-time polymerase chain reaction. To examine whether PCSK9 regulates injury of cardiomyocytes in vivo, we subjected transgenic mice with cardiac-specific overexpression of PCSK9 (PCSK9 TG) and wild-type (WT) mice to either sham surgery or ischemia/reperfusion (I/R) surgery.

Results

Under hypoxic conditions, the Wnt/β-catenin signaling pathway-related genes were downregulated in HL-1 cells, as evidenced by lower Lrp5 and active phospho-β-catenin expression levels (0.5-fold, n=3, p<0.01). After H/R, the Wnt/β-catenin-related genes were recovered (1.5-fold, p<0.01) in the control group but not in the PCSK9 overexpressed group. In the luciferase reporter assay results, PCSK9 overexpression inhibited the recovery of β-catenin transcriptional activity after H/R, in contrast to the control group. Furthermore, mRNA levels of Axin2, Cyclin D1, which are the Wnt/β-catenin signaling downstream pathway targets, were down-regulated under hypoxia and recovered after H/R but did not recover in PCSK9 overexpressed cells. In the mouse I/R model, the overall protein levels of the Wnt/β-catenin signaling-related genes were down-regulated in PCSK9 TG mice compared to WT mice after I/R injury.

Conclusions

These results indicated that the regulation of PCSK9 is closely associated with the Wnt/β-catenin signaling pathway which may play a crucial role in damaged cardiomyocytes. It suggests that the regulation of PCSK9 could be a therapeutic target in patients with ischemic cardiomyopathy.

Funding Acknowledgement

Type of funding sources: None.

Extraction of volatile organic compounds from leaves of Ambrosia artemisiifolia L. and Artemisia annua L. by headspace-solid phase micro extraction and simultaneous distillation extraction and analysis by gas chromatography/mass spectrometry

This study was designed to analyze the volatile organic compounds in the leaves of Ambrosia artemisiifolia L. and Artemisia annua L. from Korea. For extraction of volatile compounds, headspace-solid phase micro extraction (HS-SPME) and simultaneous distillation extraction (SDE) were applied and analyzed by gas chromatography/mass spectrometry (GC/MS). From the results, SDE extraction was found to give the highest concentration of volatile compounds with an average concentration of 1,237.79 mg/kg for A. annua L. leaves compared to 1,122.73 mg/kg by HS-SPME technique. A total of 116 volatile organic compounds were identified, including 76 similar volatile organic compounds detected by both the methods of extraction in leaves of subject species at varying concentrations. Among these 33 volatile organic compounds were reported for the first time from the subject plant species. Thus the present research findings extend the characterization of volatile organic compounds from leaves of A. annua L. and A. artemisiifolia L. species and reported some distinguishing compounds which may be used for their discrimination.

Elemental composition of pork meat from conventional and animal welfare farms by inductively coupled plasma-optical emission spectrometry (ICP-OES) and ICP-mass spectrometry (ICP-MS) and their authentication via multivariate chemometric analysis

The demand of consumers from around the world for natural, nutritional and palatable pork meat is increasing with time. This study analyzed macro (Ca, K, Mg, Na, P), micro (Fe, Zn, Cr, Mn, Ni, Cu, Se, Sr, Cs), trace (Li, Be, V, Co, Ga, Ba, U), and toxic trace (As, Cd, TI, and Pb) elements of pork meat from conventional and animal welfare farms in South Korea. Among the elements analyzed by inductively coupled plasma-optical emission, and mass spectrometric (ICP-OES, ICP-MS) techniques, K, Fe, Mn, and Ni content were higher in animal welfare pork meat. The trace and toxic trace elements content were lower than the standard values. The principal component and linear discriminant analyses (PCA, LDA) explained the highest variance (99.82%, 99.00%) of the group based on toxic elements. These findings can thus be used to evaluate animal welfare and conventional farms pork meat quality in South Korea as well as worldwide.

In vitro evaluation of migratory capacity of human liver stem cells influenced by soluble factors

Although several studies have addressed the engraftment of stem cells into the liver, the exact mechanisms in vivo remain unclear. In this study, we investigated the effects of soluble factors on cell migration using purified, expanded human liver stem cells (HLSCs) obtained from a pediatric liver resection. Using a in vitro transwell migration assay, we evaluated the migratory capacity of HLSCs under the influence of the cytokines tumor necross factor- [TNF]-α, interleukin [IL]-6, and interferon (IFN)-γ or the growth factors vascular endothelial growth factor [VEGF], basic fibroblast growth factor [bFGF], and hepatocyte growth factor [HGF], which are known to be highly secreted during liver injury. We also evaluated the migratory capacity indirectly influenced by cryopreserved human hepatocytes. The migration across the transwell membrane was promoted by VEGF, bFGF, TNF-α, IFN-γ, or hepatocytes. The cryopreserved human hepatocytes especially induced significant migration. These results suggested the presence of unidentified soluble factors from hepatocytes. This experiment described a reliable system for quantitative migration studies to broaden our understanding of the directional nature of cell migration.

The effect of hot pressing on the physical properties of glass reinforced hydroxyapatite

Hydroxyapatite (HA), being of physiological importance, can be developed synthetically for implant application. A number of avenues have been explored in order to improve the physical and biological properties of a variety of hydroxyapatite composites. However, the fact remains, hydroxyapatite lacks the mechanical properties needed to sustain high loads. This study investigates the advantages of hot pressing on the physical properties of HA and glass reinforced HA (GR-HA). The results show a significant enhancement in the mechanical properties of GR-HA composites compared to HA e.g. flexural bending strength values were given at 91.75 and 88.87 M Nm(-2) for GR-HA (CP15F) and GR-HA (CP20F) respectively, compared to 78.9 M Nm(-2) for HA. The results for other properties such as elastic modulus, fracture toughness, Vicker's hardness, density and porosity also demonstrate the benefit of adding phosphate based glasses as a sintering aid. This is supported by XRD analysis, highlighting the presence of a secondary phase (beta-TCP) in GR-HA systems and the positive effect it has on the physical properties. It must be brought to attention that densification of hot pressed HA and GR-HA composites is reached at a lower temperature compared to a previous study on the same materials that have undergone pressureless sintering.

Effects of ion beam-assisted deposition of hydroxyapatite on the osseointegration of endosseous implants in rabbit tibiae

The aim of this study was to evaluate the effects of coating implants with hydroxyapatite (HA) by an ion beam-assisted deposition (IBAD) method and to compare them with implants prepared with sand-blasted and machined surfaces. Examination of osteoblast cultures displayed no difference in the secretion of alkaline phosphatase (ALP) between the various surfaces, but the IBAD-HA specimen showed low ALP secretion (P < .05). Removal torque tests showed that implants coated with HA by the IBAD method had values similar to the implants with a sandblasted surface, but values for the machined-surface implants differed. Implants placed in a group of ovariectomized rabbits showed lower mechanical test values than implants placed in sham-operated rabbits (P < .05). Implants coated with HA by the IBAD method demonstrated the highest mean bone-to-metal contact ratio on all threads and on the 3 best consecutive threads, followed by the implants with a sandblasted surface and implants with a machined surface (P < .05). Hydroxyapatite-coated implants showed a slightly higher bone-to-implant contact ratio than sandblasted implants, but no statistically significant difference was seen between the 2 materials. The implants placed in ovariectomized rabbits showed lower amounts of bone-to-metal contact than the implants placed in sham-operated rabbits, but no statistically significant difference was seen between the 2 groups. Evaluation of bone volume on all threads and the 3 best consecutive threads showed no statistically significant difference among the different surface treatment groups, but lower bone volume was seen in the ovariectomized rabbits than in the sham-operated animals (P < .05).

MPP(+) downregulates mitochondrially encoded gene transcripts and their activities in dopaminergic neuronal cells: protective role of Bcl-2

The effects of neurotoxins on levels of mitochondrially encoded gene transcripts in a dopaminergic neuronal cell line, MN9D, were examined following treatment with 200 microM N-methyl-4-phenylpyridinium (MPP(+)) or 6-hydroxydopamine (6-OHDA). As confirmed by a Northern blot analysis, levels of cytochrome c oxidase subunit 3 (COX III) and ATPase subunit 6 (ATPase 6) transcript were decreased in a time-dependent manner following treatment with MPP(+) but not with 6-OHDA. Accordingly, enzymatic activity of cytochrome c oxidase (COX) and the intracellular ATP content were also decreased in MPP(+)-treated cells while these remained unaltered in 6-OHDA-treated cells. In the cell death paradigm induced by MPP(+), overexpression of Bcl-2 in MN9D cells (MN9D/Bcl-2) significantly blocked MPP(+)-induced downregulation of COX III and ATPase 6 transcripts. In MN9D/Bcl-2 cells, MPP(+)-induced downregulation of COX activity and the intracellular level of ATP was also blocked. Treatment with a pan-caspase inhibitor, however, neither prevented MPP(+)-induced downregulation of COX activity nor affected intracellular level of ATP in MN9D cells. Taken together, our present data suggest that Bcl-2 may play a regulatory role in energy metabolism by preventing downregulation of mitochondrially encoded gene(s) at a point distinct from its known anticaspase activity in MPP(+)-induced dopaminergic neuronal death.

Disruption of the myocardial extracellular matrix leads to cardiac dysfunction

MMP activity with disruption of structural collagen has been implicated in the pathophysiology of dilated cardiomyopathy. To examine the role of this enzyme in cardiac function, a transgenic mouse was created that constitutively expressed human collagenase (MMP-1) in the heart. At 6 months of age, these animals demonstrated compensatory myocyte hypertrophy with an increase in the cardiac collagen concentration due to elevated transcription of type III collagen. Chronic myocardial expression of MMP-1 produced loss of cardiac interstitial collagen coincident with a marked deterioration of systolic and diastolic function at 12 months of age. This is the first animal model demonstrating that direct disruption of the extracellular matrix in the heart reproduces the changes observed in the progression of human heart failure.

Neutron radiation enhances cisplatin cytotoxicity independently of apoptosis in human head and neck carcinoma cells

Recent advances in combined modality treatment of locally advanced head and neck cancer have improved local and regional disease control and survival with better functional outcome. However, the local and regional failure rate after radiation therapy is still high for tumors that respond poorly to cisplatin-based neoadjuvant chemotherapy. This clinical observation suggests a common biological mechanism for resistance to cisplatin and photon irradiation. In this report, we investigated the molecular basis underlying cisplatin resistance in head and neck squamous carcinoma (HNSCC) cells and asked if fast neutron radiation enhances cisplatin cytotoxicity in cisplatin-resistant cells. We found that cisplatin sensitivity correlates with caspase induction, a cysteine proteinase family known to initiate the apoptotic cell death pathway, suggesting that apoptosis may be a critical determinant for cisplatin cytotoxicity. Neutron radiation effectively enhanced cisplatin cytotoxicity in HNSCCs including cisplatin-resistant cells, whereas photon radiation had little effect on cisplatin cytotoxicity. Interestingly, neutron-enhanced cisplatin cytotoxicity was associated neither with apoptosis nor with cell cycle regulation, as determined by caspase activity assay, annexin V staining, and flow cytometric analysis. Taken together, the present study provides a molecular insight into cisplatin resistance and may also provide a basis for more effective multimodality protocols involving neutron radiation for patients with locally advanced head and neck cancer.

Ion-beam-assisted deposition (IBAD) of hydroxyapatite coating layer on Ti-based metal substrate

A hydroxyapatite layer was formed on the surface of a Ti-based alloy by ion-beam-assisted deposition. The deposition methodology comprised of an electron beam vaporizing a pure hydroxyapatite target, while an Ar ion beam was focused on the metal substrate to assist deposition. All deposited layers were amorphous, regardless of the current level of the ion beam. The bond strength between the layer and the substrate increased steadily with increasing current, while the dissolution rate in a physiological saline solution decreased remarkably. These improvements were attributed to an increase in the Ca/P ratio of the layer. Without ion beam assistance, the Ca/P ratio was much lower than the stoichiometric HAp (Ca/P = 1.67). With ion-beam assistance, the Ca/P ratio of the layer increased presumably due to the high sputtering rate of P compared to that of Ca from the layer being coated.

H-ras, but not N-ras, induces an invasive phenotype in human breast epithelial cells: a role for MMP-2 in the H-ras-induced invasive phenotype

Elevated p21ras expression is associated with tumor aggressiveness in breast cancer including the extent of invasion into fat tissues, infiltration into lymphatic vessels and tumor recurrence. In the present study, we have examined the roles of H-ras and N-ras, members of the human ras gene family, in the pathogenesis of breast cancer. We show that H-ras, but not N-ras, induces an invasive phenotype in human breast epithelial cells (MCF10A) as determined by the Matrigel invasion assay, whereas both H-ras and N-ras induce anchorage-independent growth, as shown by soft agar assay. We examined the effects of H-ras and N-ras activation on the expression of MMP-2 and MMP-9, which can degrade type IV collagen, the major structural collagen of the basement membrane. We show that MMP-2 is efficiently induced by H-ras, whereas MMP-9 induction is more prominent in N-ras-activated MCF10A cells. We also show that H-ras-mediated invasiveness is significantly inhibited when the expression of MMP-2 is down-regulated, using an oligodeoxyribonucleotide complementary to the MMP-2 mRNA, or when MMP-2 activity is blocked by its inhibitor TIMP-2 (tissue inhibitors of matrix metalloproteinase-2). Our results show that the H-ras-induced invasive phenotype is associated more closely with the expression of MMP-2 in human breast epithelial cells, rather than the induction of MMP-9 expression, as shown previously for rat embryonic fibroblasts.

Influence of light intensities on dressing behavior in elderly people

With civilized environments in modern society, since the people tend to depend more on artificial illumination than on natural illumination which makes less discrepancy between day and night life, clarifying the relationship between human life and illumination is necessary. In our previous studies, we found that the subjects dressed faster with thicker clothing in the morning than in the evening when the room temperature decreased from 30 degrees C to 15 degrees C over 1 hour. We considered these results in terms of load error between the actual and set-point values in the core temperature. The present study was designed to examine the effect of bright light (3,000 lx)/dim light (50 lx) exposure (09:30 h-14:30 h) on dressing behavior and thermoregulatory responses in the elderly people during the afternoon cold exposure. Five female subjects were instructed to dress to feel comfortable when the room temperature was decreased from 30 degrees C to 15 degrees C (15:00 h-17:00 h). The subjects felt cooler and dressed more quickly with thicker clothing after dim light exposure, it is conceivable that the set-point value of core temperature is reduced under the bright light condition. We discussed these results in terms of the establishment of set-point values in the core temperature at bright light condition. If the set-point of the core temperature is lower in the bright than in the dim light condition in present experiment, the dressing behavior with thinner clothing in the bright light condition is advantageous, since it enables the core temperature to reach its set-point value more easily.

Echocardiographic assessment of cardiac function in conscious and anesthetized mice

Using a high-frequency linear transducer (15L8), we studied 1) the feasibility of performing echocardiography in nonanesthetized mice compared with mice given pentobarbital sodium (Pento) or a mixture of ketamine and xylazine and 2) the feasibility of echocardiographic evaluation of left ventricular (LV) hypertrophy, dilatation, and function in mice with two-kidney, one-clip hypertension or myocardial infarction (MI). Heart rate (HR) in awake mice was 658 +/- 9 beats/min; Pento and ketamine plus xylazine reduced HR to 377 +/- 11 and 293 +/- 19 beats/min, respectively, associated with a significant decrease in shortening fraction (SF), ejection fraction (EF), and cardiac output (CO) and an increase in LV end-diastolic (LVEDD) and end-systolic dimensions (LVESD). Mice with 4 wk of two-kidney, one-clip hypertension had increased LV mass (15.62 +/- 0. 62 vs. 22.17 +/- 1.79 mg) without altered LV dimensions, SF, EF, or CO. Mice studied 4 wk post-MI exhibited obvious LV dilatation and systolic dysfunction, as evidenced by increased LVEDD and LVESD and decreased SF, EF, and CO. Our findings clearly show the adverse impact of anesthesia on basal cardiac function and the difficulty in interpreting data obtained from anesthetized mice. We believe this is the first study to demonstrate the feasibility of using echocardiography to assess cardiovascular function in the nonanesthetized mouse.

Ginsenoside RH-2 induces apoptotic cell death in rat C6 glioma via a reactive oxygen- and caspase-dependent but Bcl-X(L)-independent pathway

We used the rat C6 gliomal cell line to investigate the potential role of ginsenoside Rh2 (G-Rh2) in brain tumor. G-Rh2 induced many apoptotic manifestations in C6 gliomal cells as evidenced by changes in cell morphology, generation of DNA fragmentation, activation of caspase and production of reactive oxygen species (ROS). As a result, cotreatment with antioxidants or a broad-spectrum caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone effectively attenuated G-Rh2-induced cell death. However, specific cleavage of poly(ADP-ribose)polymerase into 85 kDa protein was not detected as demonstrated in many other apoptotic paradigms. Expression levels of Bcl-2 and Bax remained unchanged following G-Rh2 treatment. Furthermore, G-Rh2-induced cell death in C6 gliomal cells overexpressing antiapoptotic protein, Bcl-X(L), was comparable to that in parental cells. Taken together, our data indicate that G-Rh2-induced cell death is mediated by the generated ROS and the activation of caspase pathway in a Bcl-X(L)-independent manner.

Inhibition of chitin synthase II by catechins from stem bark of Taxus cuspidata

Two flavonoids, (+/-)-catechin and (-)-epicatechin, were isolated from the stem bark of Taxus cuspidata by monitoring chitin synthase II inhibitory activity. The compounds inhibit chitin synthase II with an IC50 of 15 and 29 micrograms/ml, respectively and appear to be selective for chitin synthase II. They did not inhibit chitin synthase III.

Platelet-derived growth factor (PDGF)-signaling mediates radiation-induced apoptosis in human prostate cancer cells with loss of p53 function

Platelet-derived growth factor (PDGF) signals a diversity of cellular responses in vitro, including cell proliferation, survival, transformation, and chemotaxis. PDGF functions as a "competence factor" to induce a set of early response genes expressed in G1 including p21WAF1/CIP1, a functional mediator of the tumor suppressor gene p53 in G1/S checkpoint. For PDGF-stimulated cells to progress beyond G1 and transit the cell cycle completely, progression factors in serum such as insulin and IGF-1 are required. We have recently shown a novel role of PDGF in inducing apoptosis in growth-arrested murine fibroblasts. The PDGF-induced apoptosis is rescued by insulin, suggesting that G1/S checkpoint is a critical determinant for PDGF-induced apoptosis. Because recent studies suggest that radiation-induced signal transduction pathways interact with growth factor-mediated signaling pathways, we have investigated whether activation of the PDGF-signaling facilitates the radiation-induced apoptosis in the absence of functional p53. For this study we have used the 125-IL cell line, a mutant p53-containing, highly metastatic, and hormone-unresponsive human prostate carcinoma cell line. PDGF signaling is constitutively activated by transfection with a p28v-sis expression vector, which was previously shown to activate PDGF alpha- and beta- receptors. Although the basal level of p21WAF1/CIP1 expression and radiation-induced apoptosis were not detectable in control 125-IL cells as would be predicted in mutant p53-containing cells, activation of PDGF-signaling induced expression of p21WAF1/CIP1 and radiation-induced apoptosis. Our study suggests that the level of "competence" growth factors including PDGF may be one of the critical determinants for radiation-induced apoptosis, especially in cells with loss of p53 function at the site of radiotherapy in vivo.

Influence of different light intensities during the daytime on evening dressing behavior in the cold

The primary purpose of this study was to determine the effect of bright light exposure during the daytime on dressing behavior in the cold. Seven female volunteers were exposed to bright light of 4,000 lx ("Bright") or dim light of 10 lx ("Dim") from 10 h to 18 h, complete darkness during the sleep period (22:30 h-06:00 h), and 10 lx for the rest of the time. The subjects were instructed to dress to remain comfortable when the ambient temperature was decreased from 30 degrees to 15 degrees C (20:30 h-22:30 h). Most subjects dressed more quickly and with thicker clothing in the Dim condition and felt cooler during the last 30 min of the temperature fall. The rectal temperature showed clear circadian rhythm both under Bright and Dim conditions, but it was significantly lower during sleep in the Bright condition. It is suggested that the set-point of core temperature is reduced at night during the Bright condition.

Effects of the menstrual cycle on dressing behavior in the cold

The purpose of the present study was to determine the effect of the menstrual cycle on dressing behavior in cold exposure. Rectal and skin temperatures, temperature sensation and metabolic rate were measured in seven women during the luteal (L) and the follicular (F) phases of the menstrual cycle, as was their dressing behavior in these two phases. The subjects were instructed to dress so as to feel comfortable when the ambient temperature was decreased from 30 degrees C to 15 degrees C (07:00-09:00). Most subjects dressed more quickly and with thicker clothing in the L phase. They felt cooler in the L phase during the last 30 min of the temperature fall. Rectal and skin temperatures showed significant differences between L and F phases and metabolic rate was significantly higher in the L phase. The results can be interpreted in terms of the establishment of a higher set-point in core temperature during the L phase.

Effects of endoscopic variceal ligation in lower esophageal motor function: a prospective study

OBJECTIVES

Endoscopic variceal ligation (EVL), a recently developed method for controlling active variceal bleeding and eradicating esophageal varices, has similar efficacy to endoscopic injection sclerotherapy (EIS) and is known to have a minimal risk of complications and fewer complications in the lower esophagus. However, since the site of EVL is chiefly done in the lower esophagus, we prospectively evaluated to investigate the effect of EVL on the lower esophageal motor function.

METHODS

We evaluated the severity of esophageal varix with the endoscopy and the lower esophageal manometry in 27 patients who had no history of interventional therapy, for varices before EVL, 3 weeks and 6 months after the last EVL session.

RESULTS

The EVL caused considerable diminution in the size of esophageal varix by a mean 8.2 (range 3-21) ligations in mean 1.7 (range 1-3) sessions. In most of the cases, the varices reappeared and enlarged when the procedure of EVL was stopped. There were two different types of changes (intermediate and late) in the lower esophageal motility. The intermediate post-EVL effects were the increase of peristaltic contraction amplitude and duration in the lower esophageal body after EVL. The late post-EVL effects were the prolongation of lower esophageal sphinctor (LES) relaxation duration and speedier peristaltic velocity in the lower esophageal body.

CONCLUSIONS

We conclude from these findings that the intermediate post-EVL effect may be transient and the increase of peristaltic wave was due to diminution of esophageal varix.

Effects of time of day on dressing behavior under the influence of ambient temperature fall from 30 degrees C to 15 degrees C

The present paper is aimed at determining whether the dressing behavior for temperature regulation in cold is under the influences of circadian control. The half-naked subjects were instructed to dress in the garments they felt comfortable when the room temperature began to decrease from 30 degrees C to 15 degrees C in 1 h. To determine the effects of brain temperature fall on the dressing behavior, we used face cooling with cool air for 30 min before the room temperature began to decrease. We also studied the effects of wearing a hat on dressing behavior. Rectal temperature, tympanic temperature, skin temperature at seven sites, and thermal sensation were recorded. Major findings are summarized as follows: 1) the subjects dressed faster with thicker clothing in the morning than in the evening; 2) the subjects with face cooling dressed faster with thicker clothing than the subjects without face cooling; 3) the subjects without a hat dressed more rapidly with thicker, heavier clothing. These results were discussed in terms of load error between actual and set-point values in the core temperature.