Regulation of NF-E2 activity in erythroleukemia cell differentiation

The erythroid transcription factor NF-E2 is an obligate heterodimer composed of two different subunits (p45 and p18), each containing a basic region-leucine zipper DNA binding domain, and it plays a critical role in erythroid differentiation as an enhancer-binding protein for expression of the beta-globin gene. We show here that dimethyl sulfoxide treatment of wild-type murine erythroleukemia cells, but not a mutant clone of dimethyl sulfoxide-resistant cells, increases NF-E2 activity significantly, which involves both up-regulation of DNA binding and transactivation activities. Both activities were reduced markedly by treatment of cells with 2-aminopurine but not by genistein. Activation of the Ras-Raf-MAP kinase signaling cascade increased NF-E2 activity significantly, but this was suppressed when MafK was overexpressed. Domain analysis revealed an activation domain in the NH2-terminal region of p45 and a suppression domain in the basic region-leucine zipper of MafK. These findings indicate that induction of NF-E2 activity is essential for erythroid differentiation of murine erythroleukemia cells, and serine/threonine phosphorylation may be involved in this process. In addition, they also suggest that a MafK homodimer can suppress transcription, not only by competition for the DNA binding site, but also by direct inhibition of transcription. Hence, MafK may function as an active transcription repressor.

High expression of alpha-1-6 fucosyltransferase during rat hepatocarcinogenesis

Alpha-1-6 fucosylated alpha-fetoprotein (AFP) is known to be elevated in patients with primary hepatoma and has been suggested as being useful as an early indicator and predictor of the poor prognosis for hepatoma. Although GDP-L-fucosyl-N-acetyl-beta-D-glucosaminide alpha-1-6 fucosyltransferase (alpha-1-6 FucT), is the key enzyme involved in alpha-1-6 fucosylation of AFP, when and how the expression of alpha-1-6 FucT is enhanced during hepatocarcinogenesis is unknown. Recently, we established a convenient assay method for this enzyme and were successful in the purification and cDNA cloning of alpha-1-6 FucT from human gastric cancer, as well as from porcine brain. In the present study, levels of alpha-1-6 FucT activity and mRNA expression have been determined during hepatocarcinogenesis in LEC rats which spontaneously develop hereditary hepatitis and hepatoma. The fetal liver contained the highest enzymatic activity, which tended to increase in inverse proportion to gestation. The enzymatic activity was significantly increased in hepatoma tissues as compared with uninvolved adjacent tissues. Northern-blot analysis revealed high expression of alpha-1-6 FucT mRNA in hepatoma tissues, whereas the expression was fairly low in normal, hepatitis and uninvolved adjacent liver tissues. While the fetal liver had the highest enzymatic activity, the expression of alpha-1-6 FucT mRNA was low, suggesting that another alpha-1-6 FucT is induced in fetal liver or that post-translational modification occurs. High expression of alpha-1-6 FucT was also observed in 3'-MeDAB-induced rat hepatomas and some rat hepatoma cell lines. Collectively, alpha-1-6 FucT was strongly enhanced from an early stage of hepatocarcinogenesis and was maintained at a high level in rat hepatomas.

Alternative promoters regulate transcription of the mouse GATA-2 gene

Transcription factor GATA-2 has been shown to be a key regulator in hematopoietic progenitor cells. To elucidate how the expression of the GATA-2 gene is controlled, we isolated the mouse GATA-2 (mGATA-2) gene. Transcription of mGATA-2 mRNAs was found to initiate from two distinct first exons, both of which encode entirely untranslated regions, while the remaining five exons are shared by each of the two divergent mRNAs. Reverse transcriptase-polymerase chain reaction analysis revealed that GATA-2 mRNA initiated at the upstream first exon (IS) in Sca-1+/c-kit+ hematopoietic progenitor cells, whereas mRNA that initiates at the downstream first exon (IG) is expressed in all tissues and cell lines that express GATA-2. While the structure of the IG exon/promoter shows high similarity to those of the Xenopus and human GATA-2 genes, the IS exon/promoter has not been described previously. When we examined the regulation contributing to IS transcription using transient transfection assays, we found that sequences lying between -79 and -61 are critical for the cell type-specific activity of the IS promoter. DNase I footprinting experiments and electrophoretic mobility shift assays demonstrated the binding of transcription factors to this region. These data indicate that the proximal 80 base pair region of IS promoter is important for the generation of cell type-specific expression of mGATA-2 from the IS exon.

An expression system of rat calmodulin using T7 phage promoter in Escherichia coli

An efficient expression system of rat calmodulin in Escherichia coli is presented. To express rat calmodulin cDNA, we employed a pET expression vector which contains the T7 phage promoter and terminator. After transformation of E. coli BL21(DE3) strain which carries T7 phage RNA polymerase inducible with isopropyl-beta-D-thiogalactopyranoside, induction of the expression, and chromatography of soluble proteins on a phenyl-Sepharose column, about 250 mg of recombinant rat calmodulin was obtained from 1 liter of E. coli culture. The recombinant calmodulin lacked the N-terminal methionine, and posttranslational modifications such as Nalpha-acetylation and methylation. This system facilitates the large amount preparation of calmodulin and the mutant proteins required for the structural analysis by NMR spectrometry and/or X-ray crystallography.

Normal bladder wall morphology in Gd-DTPA-enhanced clinical MR imaging using an endorectal surface coil and histological assessment of submucosal linear enhancement using [14C]Gd-DOTA autoradiography in an animal model

OBJECTIVE

The purpose of this study was to investigate normal bladder wall morphology in gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced magnetic resonance (MR) imaging using an endorectal surface coil and to perform histological assessment of submucosal linear enhancement with experimental [14C]-gadolinium-tetraazacyclododecane-tetraacetic acid (Gd-DOTA) autoradiography.

METHODS AND MATERIAL

MR imaging of the bladder was performed using an endorectal coil in 13 consecutive patients with bladder carcinoma and T1-, T2-, and Gd-DTPA-enhanced spin-echo images of the bladder wall were compared. After injection of [14C]Gd-DOTA into a hamster, autoradiograms of the bladder wall were obtained and compared with serial histological sections.

RESULTS

The normal bladder wall appeared as a homogeneous layer of intermediate intensity on T1-weighted images. After administration of Gd-DTPA, the bladder wall was visualized as three layers: an inner thin layer of low intensity, a middle layer of marked enhancement, and a thick outer layer of intermediate intensity. The autoradiograms demonstrated dense accumulation of [14C]Gd-DOTA in the submucosal layer. Thus, the inner, middle, and outer layers corresponded to the mucosa, submucosa, and muscularis propria, respectively. The thickness of the bladder wall demonstrated on T2-weighted images was almost equal to that of the outer layer on enhanced T1-weighted images. Thus, T2-weighted images revealed only the muscle layer as an intermediate-intensity band. In the preliminary clinical study, MR imaging invariably showed accurate stages of the bladder carcinoma in 13 patients.

CONCLUSION

In MR imaging of the normal bladder wall, the submucosa was strikingly enhanced after Gd-DTPA administration, separating the bladder wall into three layers. This may have a potential role in the staging of bladder tumors.

CT-guided biopsy of pulmonary nodules less than 3 cm: usefulness of the spring-operated core biopsy needle and frozen-section pathologic diagnosis

OBJECTIVE

The purpose of this study was to improve the diagnostic accuracy of CT-guided biopsy of small lung nodules with the aid of frozen-section histopathologic diagnosis.

SUBJECTS AND METHODS

Since 1993, we have evaluated 52 lung nodules smaller than 3 cm with CT-guided transthoracic biopsy. Thirty-five lesions were malignant and 17 were benign. Biopsy always started with a 20-gauge spring-operated core biopsy needle. Tissue samples were sent to the pathology laboratory immediately after biopsy for histopathologic diagnosis of the frozen sections.

RESULTS

In 47 (90%) of 52 lesions, sufficient material for histologic diagnosis was obtained, including 34 (97%) of 35 malignant lesions and 13 (76%) of 17 benign lesions. In the 13 benign lesions for which histologic sampling was successful, a specific diagnosis of benign was made for 10 lesions (77%). In three cases, the sample was too small to make a histologic specimen, but cytologic study using the same sample led to the correct final diagnosis: one as malignant and two as benign. In the remaining two cases, biopsy was unsuccessful. The lesions were both 1 cm in size and were found to be benign on follow-up studies.

CONCLUSION

CT-guided biopsy with the aid of frozen-section specimens using small-bore spring-operated core needles is a feasible technique with good results in the histologic diagnosis of small lung lesions.

Platelet-activating factor and edema surrounding meningiomas

OBJECT

The purpose of this study was to evaluate the involvement of platelet-activating factor (PAF) in the formation of edema surrounding meningiomas.

METHODS

Volumes of tumor and peritumoral edema were calculated based on three-dimensional reconstructed magnetic resonance images in 31 patients with intracranial meningiomas. The authors measured tumor concentrations of PAF and localized PAF and leukocytes in the tumors by using immunohistochemical studies. A significant positive correlation was found between peritumoral edema and PAF concentration. Both PAF and leukocyte common antigen were localized to the interstitial tissue of the tumor. Edema production was related to the degree of leukocyte infiltration in meningiomas.

CONCLUSIONS

It appears that PAF, which may arise from infiltrating leukocytes, is important to the development of peritumoral edema in patients with meningioma.

[The study of genetic changes in colorectal cancer accompanied with ulcerative colitis]

The usefulness of gene information was studied when used in conjunction with a morphological diagnosis of either dysplasia or carcinoma that later develops into ulcerative colitis (UC). The cases investigated consisted of those operated on for UC with carcinoma complications and those operated on for UC over 7 years previously without carcinoma complications. Ras and DCC were examined for the presence of any point mutations in codon 12 and polymorphism in codon 201 using the PCR-RFLP method, while p53 was also studied immunohistologically. A mutation in ras was found in 25% of the UC-IV cases and also in 17% of the UC-III cases, while no mutation at all was found in the UC-I and UC-II cases. p53 showed a high rate of positivity in the UC-IV and UC-III cases with carcinoma complications, while it was negative in all cases in the control group cases. Gly in DCC codon 201 was also found in many cases including the control group. This study demonstrated that a gene aberration can thus influence the pathophysiology and cancerization of UC and therefore the p53 findings were thus considered to be useful in the morphological diagnosis of dysplasia and carcinoma.

Multiple single sections Turbo FLASH MR arterial portography in the detection of hepatic neoplasms

OBJECTIVE

To determine the sensitivity of multiple single sections Turbo FLASH MR arterial portography (MRAP) in the detection of hepatic neoplasms.

METHODS AND PATIENTS

Twelve patients with hepatic mass underwent MRAP prior to hepatic resection. Findings of MRAP were compared with surgical specimen and intra-operative ultrasonography (US).

RESULTS

A total of 19 separate malignant neoplastic nodules were identified in the resected specimens or intra-operative ultrasonography. The sensitivity was 89.5% (17/19) for MRAP. MRAP depicted all neoplasms more than 1.0 cm in diameter. Two lesions not depicted on MRAP had a diameter of 5 and 9 mm, respectively. One lesion identified by MRAP was confirmed to false positive lesion by intra-operative US.

CONCLUSION

Multiple single sections Turbo FLASH MRAP may be a valuable adjunct for pre-operative detection of malignant hepatic neoplasms.

Antibody dependent cell-mediated cytotoxicity using hepatocellular carcinoma reactive monoclonal antibody

We have established monoclonal antibodies from mice immunized with the human hepatocellular carcinoma cell line, hu-H2. One of the antibodies, designated 523(KY-3), was reactive with this hepatocellular carcinoma cell line as well as with the human pancreatic cancer cell line, MIA. Another monoclonal antibody, 512(KY-2), only reacted with the hepato-cellular carcinoma cell lines. Neither antibody reacted with the colon cancer cell line CW3. Pretreatment of peripheral blood mononuclear cells with 523 resulted in enhancement of their natural cytotoxicity to hu-H2 (9.0 vs 18.4% in subject 1, 3.5 vs 14.7% in subject 2, and 14.2 vs 31.0% in subject 3). In contrast, such antibody mediated enhanced natural cytotoxicity was not found by pretreatment of the same peripheral blood mononuclear cell with 512. With the similarity in reactivity of 523, this antibody dependent enhancement was found in natural cytotoxicity to hu-H2 and MIA but not to CW3. Based on the facts that 523 did not have a direct cytopathic effect on these tumours and that this 523-mediated enhanced natural cytotoxicity was inhibited by anti-FcgammaRIII antibody, we concluded that the 523-mediated enhanced cytotoxicity reflects its activity to induce antibody dependent cytotoxic cells. Thus, these results demonstrate that several distinct tumour-specific antigens exist in hepatocellular carcinoma (HCC) and that one of them represents a potentially useful target for immunotherapy of human hepatocellular carcinoma.

The identification of cDNAs that affect the mitosis-to-interphase transition in Schizosaccharomyces pombe, including sbp1, which encodes a spi1p-GTP-binding protein

Perturbations of the spi1p GTPase system in fission yeast, caused by mutation or overexpression of several regulatory proteins, result in a unique terminal phenotype that includes condensed chromosomes, a wide medial septum, and a fragmented nuclear envelope. To identify potential regulators or targets of the spi1p GTPase system, a screen for cDNAs whose overexpression results in this terminal phenotype was conducted, and seven clones that represent three genes, named med1, med2, and med3 (mitotic exit defect), were identified. Their genetic interaction with the spi1p GTPase system was established by showing that the spi1p guanine nucleotide exchange factor mutant pim1-d1ts was hypersensitive to their overexpression. med1 encodes a homologue of the human Ran-binding protein, RanBP1, and has been renamed sbp1 (spi1-binding protein). sbp1p binds to spi1p-GTP and costimulates the GTPase-activating protein (GAP)-catalyzed GTPase activity. Cells in which sbp1p is depleted or overproduced phenocopy cells in which the balance between spi1p-GTP and spi1p-GDP is perturbed by other means. Therefore, sbp1p mediates and/or regulates the essential functions of the spi1p GTPase system. med2 and med3 encode novel fission yeast proteins that, based on our phenotypic analyses, are likely to identify additional regulators or effectors of the spi1p GTPase system.

Power Doppler sonography of cervical lymph nodes in patients with head and neck cancer

PURPOSE

The purpose of this preliminary study was to evaluate the usefulness of power Doppler sonography in differentiating metastatic from nonmetastatic cervical lymph nodes in patients with cancer.

METHODS

Histologically proved metastatic (n = 71) and nonmetastatic (n = 220) lymph nodes were examined with power Doppler sonography in 77 patients with head and neck cancer. Power Doppler sonography was assessed for its ability to differentiate metastatic from nonmetastatic lymph nodes.

RESULTS

Power Doppler sonography showed characteristic features of parenchymal blood flow signal in 59 (83%) of the 71 metastatic lymph nodes. By contrast, only four (2%) of the 220 nonmetastatic nodes showed these power Doppler signals. In addition, power Doppler sonography showed high levels of sensitivity (83%) and specificity (98%) in depicting metastatic lymph nodes, which were superior to the values (66% sensitivity and 92% specificity) obtained by applying size criteria (transverse to longitudinal ratio). However, a combination of the two criteria (parenchymal color signal and transverse to longitudinal ratio) improved diagnostic accuracy to 92% sensitivity and 100% specificity.

CONCLUSION

Our preliminary findings suggest that the power Doppler criteria of no hilar flow, peripheral parenchymal nodal flow, and a transverse to longitudinal ratio of more than 0.65 together constitute a powerful tool for depicting metastatic lymph nodes in patients with cancer.

Percutaneous long-term arterial access with implantable ports. Direct subclavian approach with US

PURPOSE

To clarify the clinical feasibility of getting a long-term arterial access at the subclavian region by directly puncturing the artery under ultrasound guidance.

MATERIALS AND METHODS

Percutaneous placements of arterial infusion catheters with implantable ports were performed in 30 patients with malignant abdominal tumors. The axillary artery in the subclavian region was punctured directly with an 18G needle under ultrasound guidance. Using the Seldinger technique, a 5Fr catheter was placed with its tip in the hepatic or the other tumor-supplying arteries. The catheter was connected to an implantable port, and both of them were embedded in the subcutaneous pocket.

RESULTS

Percutaneous placements of infusion catheters were successfully performed in 29 cases. Transarterial chemotherapy through implanted ports was done uneventfully in 26 patients, while in the other three cases, catheter dislodgment occurred. Two local haematomas, one wound infection and one cerebellar infarction were also experienced.

CONCLUSION

Ultrasound-guided subclavian approach is a minimally invasive way of implanting an infusion catheter for chemotherapy, although its indication for severely atherosclerotic patients should be limited.

High expression of alpha-1-6 fucosyltransferase during rat hepatocarcinogenesis

Alpha-1-6 fucosylated alpha-fetoprotein (AFP) is known to be elevated in patients with primary hepatoma and has been suggested as being useful as an early indicator and predictor of the poor prognosis for hepatoma. Although GDP-L-fucosyl-N-acetyl-beta-D-glucosaminide alpha-1-6 fucosyltransferase (alpha-1-6 FucT), is the key enzyme involved in alpha-1-6 fucosylation of AFP, when and how the expression of alpha-1-6 FucT is enhanced during hepatocarcinogenesis is unknown. Recently, we established a convenient assay method for this enzyme and were successful in the purification and cDNA cloning of alpha-1-6 FucT from human gastric cancer, as well as from porcine brain. In the present study, levels of alpha-1-6 FucT activity and mRNA expression have been determined during hepatocarcinogenesis in LEC rats which spontaneously develop hereditary hepatitis and hepatoma. The fetal liver contained the highest enzymatic activity, which tended to increase in inverse proportion to gestation. The enzymatic activity was significantly increased in hepatoma tissues as compared with uninvolved adjacent tissues. Northern-blot analysis revealed high expression of alpha-1-6 FucT mRNA in hepatoma tissues, whereas the expression was fairly low in normal, hepatitis and uninvolved adjacent liver tissues. While the fetal liver had the highest enzymatic activity, the expression of alpha-1-6 FucT mRNA was low, suggesting that another alpha-1-6 FucT is induced in fetal liver or that post-translational modification occurs. High expression of alpha-1-6 FucT was also observed in 3'-MeDAB-induced rat hepatomas and some rat hepatoma cell lines. Collectively, alpha-1-6 FucT was strongly enhanced from an early stage of hepatocarcinogenesis and was maintained at a high level in rat hepatomas.

Measurement of hemodynamics of auditory cortex using magnetoencephalography and near infrared spectroscopy

Near infrared (NIR) spectroscopy, a non-invasive optical method for monitoring hemodynamics, was applied to record evoked auditory response of the human brain. Our newly developed system detected the amount of oxygenated and deoxygenated hemoglobin in the area of the local brain located beneath the probes. In the study, we used magnetoencephalography (MEG) and NIR spectroscopy to observe the blood component change near the auditory cortex. The sound stimulus of 1 kHz sine wave at 70 dB SPL was used to elicit evoked responses in both experiments. The active region of the auditory cortex was determined by MEG, and the same area was examined by the NIR system. The results from the NIR experiments showed significant increases of total hemoglobin and deoxygenated hemoglobin, indicating that both blood flow and oxygen consumption at the cortical area increased in response to the sound stimuli. The NIR recordings at the two different depths revealed that the increases of local blood flow and oxygen consumption were observed at depths ranging between 20 and 30 mm from the scalp.

MARCKS, a major protein kinase C substrate, assumes non-helical conformations both in solution and in complex with Ca2+-calmodulin

MARCKS, a major cellular substrate for protein kinase C, plays important roles in various cellular functions and its functions are regulated by calmodulin. We have studied the conformational properties of recombinant human MARCKS in solution and in complex with calmodulin. Circular dichroism (CD) spectra showed a high content of random coil in physiological solution. When MARCKS or MARCKS-derived calmodulin-binding peptide was complexed with Ca2+-calmodulin, little change was observed in the CD spectra, suggesting that MARCKS binds with calmodulin in a non-helical conformation, which is unique among the calmodulin-binding proteins.

[Percutaneous sclerotherapy for chyluria with leg edema: a case report]

A 45-year-old woman with left leg edema was admitted to our hospital because of chyluria from the previous year. Her left leg edema appeared after Caesarean section for her first delivery and hysterectomy at the age of 31. Because microfilaria was not detected, she was diagnosed with postoperative lymphangiomatosis. The instillation of 0.1-0.5% silver nitrate into the renal pelvis was not effective. We however, after percutaneous sclerotherapy to the left inguinal lymph nodes with doxycycline, the chyluria disappeared and her left leg edema improved. Then, the surplus skin of her left lower leg was resected. We considered percutaneous sclerotherapy to be a good procedure for chyluria due to postoperative lymphangiomatosis.

Influence of HLA haplotypes on the clinical courses of individuals infected with hepatitis C virus

The human leukocyte antigen is a crucial genetic factor that initiates or regulates immune response by presenting foreign or self antigens to T lymphocytes. The aim of this study was to investigate whether HLA polymorphism is associated with the onset or progression of liver injury in chronic hepatitis C virus (HCV) infection. We determined HLA class I antigens and class II alleles in 130 hepatitis C virus (HCV)-infected patients (33 carriers with persistently normal alanine transaminase [ALT] values and 97 patients with chronic liver disease [CLD]). HLA class I (A, B) was typed serologically, and class II (DRB1, DQB1) was typed by means of polymerase chain reaction-restriction fragment length polymorphism methods. The frequencies of DRB1*0405 and DQB1*0401 were higher in HCV-infected patients than in uninfected subjects. Among HCV-infected patients, the frequencies of B54, DRB1*0405, and DQB1*0401 were significantly higher in patients with CLD than in those carriers with persistently normal ALT values, whereas DRB1*1302, DRB1*1101, and DQB1*0604 were more frequently found in carriers with persistently normal ALT values than in patients with CLD. From extended haplotype analyses, in carriers with B54-DRB1*0405-DQB1*0401 haplotype, the risk of having liver injury was 13.2 times greater than in carriers with DRB1*0405-DQB1*0401 but without B54 [P = 0.0015, Haldane odds ratio = 13.2 (95% confidence interval, 1.7-103.8)]. In contrast, carriers with B44-DRB1*1302-DQB1*0604 had a 12.7-fold lower relative risk of developing liver injury compared to those with the haplotype containing B44 but not DRB1*1302-DQB1*0604 [P = 0.0076, Haldane odds ratio = 0.079 (0.009-0.695)]. Our findings show that extended haplotypes including class I B54 are closely associated with the progression of liver injury, whereas extended haplotypes including class II DRB1*1302-DQB1*0604 are associated with low hepatitis activity in chronic HCV infection.

Evidence for the existence of CCK-producing cells in rat pancreatic islets

BACKGROUND

Although the existence of cholecystokinin-like immunoreactivity (CCK-LI) in rat pancreas had been reported previously, it was never clearly demonstrated whether CCK is produced in rat pancreatic islets.

AIMS

The purpose of this study was to elucidate the source of the CCK-LI, the molecular properties of CCK, and the expression of the CCK gene in islet cells.

METHODS

Immunohistochemical studies of rat pancreas were carried out with different rabbit antisera against CCK-8 and CCK-related peptide including N-terminal CCK-33 (1-22) and gastrin-17, and colocalization with known islet hormones including insulin, glucagon, somatostatin, and pancreatic polypeptide was investigated. The major molecular form of CCK in the islets was determined by HPLC. RT-PCR and in situ hybridization were performed to demonstrate the presence of the CCK transcript in the pancreas.

RESULTS

CCK-LI was found in the center of the islets, colocalized with insulin in B cells. The major molecular form of CCK in the islets was CCK-8. A 350-nucleotide fragment of PCR-amplified CCK cDNA was detected in the islet as well as the duodenum by RT-PCR. In situ hybridization showed that CCK messenger RNA was located in a large portion of the islets, and this was consistent with the immunohistochemical findings.

CONCLUSION

CCK messenger RNA and immunoreactivity are expressed in adult rat pancreatic islets, indicating that CCK-producing cells are present in adult rat islets.

[A case of metastatic ureteral tumor from rectal cancer]

A 67-year-old man was referred for further examination of left hydronephrosis. He had undergone anterior resection for rectal cancer 2 years previously and also right lobectomy for a solitary hepatic metastasis one year postoperatively. Antegrade pyelography demonstrated a filling defect in middle portion of the left ureter. Cytology of the aspirated urine was class V. Left nephrourete-rectomy was performed. Histologically metastatic adenocarcinoma with intact ureteral mucosa was demonstrated.

Temporal effect of muscle contraction on respiratory sinus arrhythmia

The purpose of this investigation was to compare the heart rate variability at respiratory frequency (HRVRF) in muscle contractions during the inspiratory phase with that during the expiratory phase. Eight volunteers performed pedaling on a cycle ergometer, twice a cycle of respiration (4 sec) against a load of 0.25 Nm/kg BW, of which the timing was adjusted to twice during the inspiration phase (I), once during the expiration, once during the inspiration (EI), or twice during the expiration phase (E). Spectral analysis was applied to the R-R intervals of each condition. The amplitude of HRVRF in E was less than half of 1 (9 +/- 2 msec versus 23 +/- 2 msec). The results indicate that the timing of muscle contraction can affect the heart rate variability even at the frequency band of respiration.

Chronic hepatitis C associated with anti-liver/kidney microsome-1 antibody is not a subgroup of autoimmune hepatitis

To determine whether "autoimmune hepatitis type IIb" should be categorized as a subgroup of autoimmune hepatitis, we conducted a clinicopathological study of 25 adult Japanese patients who were positive for anti-liver/kidney microsome-1 (anti-LKM-1) anti-body and infected with the hepatitis C virus (HCV). Anti-LKM-1 was determined by indirect immunofluorescence and by the double immunodiffusion assays we have developed. Twenty-two patients did not present any unusual symptoms or any associated diseases during the course of their chronic HCV infection. The spectrum of HCV genotypes of these patients did not significantly differ from that of anti-LKM-1-negative Japanese patients with chronic hepatitis C. Histological examination of liver biopsy specimens showed the usual characteristics of chronic hepatitis C and lack of characteristics of autoimmune hepatitis type I. No disease-specific HLA haplotypes were noted, and HLA-DR4, which is detectable in 88.7% of Japanese patients with autoimmune hepatitis type I, was detected in only 50.0% of our group, the same rate as the background frequency. Prednisolone was effective in none of the six patients treated, but interferon was effective in six of ten treated patients (60%). From these results, we conclude that "autoimmune hepatitis type IIb" should not be categorized as autoimmune hepatitis, and that this subgroup is essentially chronic hepatitis C in which an autoantibody has been produced during the course of chronic HCV infection.

Face immersion increases vagal activity as assessed by heart rate variability

We examined whether the diving reflex without breath-holding (face immersion alone) increases vagal activity, as determined by heart rate variability. A group of 15 men [mean age 20 (SD 3) years, height 172 (SD 5) cm, body mass 68 (SD 9) kg] performed 12 trials at various breathing frequencies (5, 10, 15, 20, 30 breaths x min(-1) and uncontrolled breath) with or without face immersion. The R-R intervals of the ECG and gas exchange variables were recorded during the 2 min of each trial. The subjects immersed their faces in 8 10 degrees C water while breathing through a short snorkel. The subject sat in the same position either with or without face immersion. The mean R-R interval (RRmean), standard deviations (SD[RR]) and coefficient of variance (CV[RR]) of the R-R interval were calculated from the R-R intervals during 30-120 s. The face immersion significantly increased SD(RR) and CV(RR) (P < 0.05), and increased RRmean (P < 0.05) at 20 breaths x min(-1). Face immersion itself had no effect on oxygen uptake, tidal volume, end-tidal O2 and CO2 partial pressures. The diving reflex without breath-holding increased the heart rate variability, indicating that face immersion alone increases vagal activity.