Analytical method to examine the effects of carbon dioxide lasers on skin: a study using wrinkles induced in hairless mice

BACKGROUND AND OBJECTIVE

Investigation of the wrinkle smoothing process elicited by CO(2) laser treatment is important for understanding the mechanism involved in their repair.

STUDY DESIGN/MATERIALS AND METHODS

Hairless mice with wrinkles induced in their dorsal skin by long-term exposure to ultraviolet radiation in the wavelength range of 290-320 nm were treated with a CO(2) laser. By using this model, we investigated the external appearance, histologic changes, and the mechanical properties of the skin during the wrinkle repair.

RESULTS

Laser treatment with an appropriate intensity caused wrinkles to smooth completely. In the healing process, reepithelialization and collagen tissue regeneration in the upper dermis was observed. However, marked changes in the skin were noted, such as increases in the collagen layer and in the skin thickness, and changes in the mechanical properties of the skin, despite the favorable external appearance.

CONCLUSIONS

An abnormal state characterized by excessive collagen regeneration and other changes in the dermis occur concomitantly with wrinkle smoothing.

Progressive neuronal loss in the ventral posterior lateral and medial nuclei of thalamus in Niemann-Pick disease type C mouse brain

Niemann-Pick disease type C (NP-C) disease is a progressive and fatal neurological disorder characterized by accumulation of cholesterol and glycosphingolipids in peripheral tissues and that of glycosphingolipids in the brain. A C57BL/KsJ-npc1(spm) mutant strain is a genetically authentic model of NP-C. This study investigated neuronal cell loss and lipid accumulation in the npc1(spm) mouse brain. Nissl-staining revealed abundant swollen neurons in the neocortex, piriform cortex, hippocampus and basal ganglia at 3-4 wk of age. In addition to loss of the Purkinje cells, we found a conspicuous cell loss in the ventral posterial lateral (VPL) and medial (VPM) nuclei of thalamus, which became apparent after 4-5 wk. Biochemical analyses revealed no increase of cholesterol in the lipid extracts whereas a substantial accumulation of cholesterol was detectable in most of the large neurons by filipin staining in the brain of homozygous mice. In contrast to the diffuse staining pattern in normal brains, the neuropils of the neurons in the brain of homozygous mice were stained in a punctate pattern. The ubiquitous accumulation excludes a direct role of cholesterol in the progressive neuronal loss in the Purkinje cell layer and in the VPL and VPM of the thalamus.

Production of polyunsaturated fatty acids by polyketide synthases in both prokaryotes and eukaryotes

Polyunsaturated fatty acids (PUFAs) are essential membrane components in higher eukaryotes and are the precursors of many lipid-derived signaling molecules. Here, pathways for PUFA synthesis are described that do not require desaturation and elongation of saturated fatty acids. These pathways are catalyzed by polyketide synthases (PKSs) that are distinct from previously recognized PKSs in both structure and mechanism. Generation of cis double bonds probably involves position-specific isomerases; such enzymes might be useful in the production of new families of antibiotics. It is likely that PUFA synthesis in cold marine ecosystems is accomplished in part by these PKS enzymes.

Detection of B virus infection in cynomolgus monkeys by ELISA using simian agent 8 as alternative antigen

The use of simian agent 8 (SA8) as an antigen for B virus (BV) antibody detection was evaluated in cynomolgus monkeys. Seventy-two sera judged as positive using BV antigen were all positive when the SA8 antigen was used. Out of 28 BV-negative sera 2 were positive against the SA8 antigen and one serum was classified as indeterminate. The present data indicates that detection of BV antibody can be achieved accurately and safely by enzyme-linked immunosorbent assay (ELISA) using SA8 antigen.

Effect of insulin resistance on serum paraoxonase activity in a nondiabetic population

Paraoxonase is a high-density lipoprotein (HDL)-bound esterase that hydrolyzes various organophosphorus compounds and protects low-density lipoprotein (LDL) against accumulation of lipid peroxides. Paraoxonase activity is strongly affected by the polymorphism of the paraoxonase gene (PON1) at position 192. In addition, the enzyme activity shows a great variation within each genotype, although the underlying mechanism is unknown. Because paraoxonase activity is decreased in subjects with type 2 diabetes mellitus who have insulin resistance, we investigated the association between paraoxonase activity and insulin resistance in a nondiabetic population. The subjects were 237 healthy Japanese adults with fasting plasma glucose less than 7.0 mmol/L. Paraoxonase activity was measured using paraoxon as a routine substrate. Insulin resistance was assessed by homeostasis model assessment index (HOMA index). Paraoxonase activity was affected by HDL level. To reduce the effect of HDL on paraoxonase, paraoxonase activity/HDL ratio was used. When the subjects were divided into tertiles by HOMA index, the subjects with higher HOMA values had higher paraoxonase/HDL ratios, although the 3 groups were comparable in age, gender and the PON1 genotype distribution. Paraoxonase/HDL ratio showed significant positive correlations not only with HOMA index, but also with body mass index, waist-to-hip ratio (WHR), whereas it correlated inversely with age at borderline significance. Multiple regression analysis indicated that the association between HOMA index and paraoxonase/HDL ratio was significant and independent of PON1 genotype, age, and adipocity. The positive association between HOMA index and HDL-corrected enzyme activity was again significant when the enzyme activity was measured with diazoxon as an alternative substrate. These results suggest that insulin resistance or hyperinsulinemia is a factor contributing to the intragenotype variability of paraoxonase activity in a population without overt hyperglycemia.

Usefulness and limitation of DiBAC4(3), a voltage-sensitive fluorescent dye, for the measurement of membrane potentials regulated by recombinant large conductance Ca2+-activated K+ channels in HEK293 cells

The usefulness of bis-(1,3-dibutylbarbituric acid)-trimethine oxonol (DiBAC4(3)), a voltage-sensitive fluorescent dye, for the measurement of membrane potentials (MPs) was evaluated in HEK293 cells, where alpha or alpha plus beta1 subunits of large conductance Ca2+-activated K+ (BK) channels were expressed (HEKBK alpha and HEKBK alphabeta). The fluorescent intensity of DiBAC4(3) was measured at various potentials under voltage-clamp for calibration to estimate the absolute MP semi-quantitatively. The resting MPs measured with DiBAC4(3) were roughly comparable to those recorded with a microelectrode; the MP in HEKBK alphabeta was 10-20 mV more negative than that in native HEK. In HEKBK alpha, the membrane hyperpolarization induced by 10 microM Evans blue, a BK channel opener, was detected with DiBAC4(3). NS-1619, another BK channel opener, induced gradual but substantial change in F/F(K) even in native HEK, while the BK channel opening effect was detected. Oscillatory membrane hyperpolarization was induced in HEKBK alphabeta by application of 10 microM acetylcholine via increase in intracellular Ca2+ concentration. The oscillatory hyperpolarization was, however, detected only as a slow hyperpolarization with DiBAC4(3). It can be concluded that relatively slow effects of BK channel modulators can be semi-quantitatively measured by use of DiBAC4(3) in HEKBK, while the limited temporal resolution and possible artifacts should be taken into account.

CD28-independent costimulation of T cells in alloimmune responses

T cell costimulation by B7 molecules plays an important role in the regulation of alloimmune responses. Although both B7-1 and B7-2 bind CD28 and CTLA-4 on T cells, the role of B7-1 and B7-2 signaling through CTLA-4 in regulating alloimmune responses is incompletely understood. To address this question, we transplanted CD28-deficient mice with fully allogeneic vascularized cardiac allografts and studied the effect of selective blockade of B7-1 or B7-2. These mice reject their grafts by a mechanism that involves both CD4(+) and CD8(+) T cells. Blockade of CTLA-4 or B7-1 significantly accelerated graft rejection. In contrast, B7-2 blockade significantly prolonged allograft survival and, unexpectedly, reversed the acceleration of graft rejection caused by CTLA-4 blockade. Furthermore, B7-2 blockade prolonged graft survival in recipients that were both CD28 and CTLA-4 deficient. Our data indicate that B7-1 is the dominant ligand for CTLA-4-mediated down-regulation of alloimmune responses in vivo and suggest that B7-2 has an additional receptor other than CD28 and CTLA-4 to provide a positive costimulatory signal for T cells.

Microvolt T wave alternans in human cardiac hypertrophy: electrical instability and abnormal myocardial arrangement

INTRODUCTION

Although T wave alternans (TWA) is a promising risk marker for myocardial electrical instability, it remains unclear how the presence of TWA is related to myocardial damage.

METHODS AND RESULTS

TWA was measured in 28 patients with hypertrophic cardiomyopathy (HCM), 29 patients with hypertensive left ventricular hypertrophy (HLVH), and 15 normal volunteers using a CH2000 system. The amplitude of TWA (Valt) was measured at the lead with the maximum amplitude. Cardiac biopsy was performed in 12 HCM patients, who were divided into two groups (severe and mild) based on histologic findings of myocardial disarray and fibrosis. TWA was positive (Valt > 1.9 microV) in 61% of HCM and 31% of HLVH, despite a nearly identical left ventricular mass index (176 +/- 65 g/m2 vs 175 +/- 39 g/m2). Valt at heart rate = 110 beats/min was significantly greater in HCM with severe disarray and fibrosis than in HCM with mild disarray and in HLVH.

CONCLUSION

In HCM patients, a positive TWA test probably is related to abnormal myocardial arrangement (disarray) and/or fibrosis, and it may reflect electrical instability of the myocardium.

Crystal structure of 2-hydroxyl-6-oxo-6-phenylhexa-2,4-dienoic acid (HPDA) hydrolase (BphD enzyme) from the Rhodococcus sp. strain RHA1 of the PCB degradation pathway

2-Hydroxyl-6-oxo-6-phenylhexa-2,4-dienoic acid (HPDA) hydrolase (the BphD enzyme) hydrolyzes a ring-cleavage product of an aromatic compound generated in a biphenyl/polychlorinated biphenyl (PCB) degradation pathway of bacteria. The crystal structure of the BphD enzyme has been determined at 2.4 A resolution by the multiple isomorphous replacement method. The final refined model of the BphD enzyme yields an R-factor of 17.5 % at 2.4 A resolution with reasonable geometry. The BphD enzyme is an octameric enzyme with a 422 point-group symmetry. The subunit can be divided into core and lid domains. The active site of the enzyme is situated in the substrate-binding pocket, which is located between the two domains. The substrate-binding pocket can be divided into hydrophobic and hydrophilic regions. This feature of the pocket seems to be necessary for substrate binding, as the substrate is composed of hydrophilic and hydrophobic parts. The proposed orientation of the substrate seems to be consistent with the general catalytic mechanism of alpha/beta-hydrolases.

P-glycoprotein expression in human major and minor salivary glands

Sodium pump and carbonic anhydrase activity have been described in the salivary glands. However, it remains to be elucidated whether these energy sources are used for secretion, excretion or both. In addition, the differences in the function of excretion and the role of the excretory duct cells are currently unknown in salivary glands. Expression of P-glycoprotein (P-gp), which is an ATPase-binding efflux pump, was tested in normal major and minor salivary glands from humans. P-gp was distributed on the basolateral membrane of serous acinar cells in the major salivary glands and the minor salivary glands. In particular, it was found to be present on the basolateral membrane and cytoplasm of acinar demilunar cells in the anterior lingual gland. Intense expression was identified in the basolateral membrane of the striated duct cells of the major salivary glands. P-gp was distinctly positive in the basolateral and/or luminal membranes of the initial part and in the luminal membrane of the terminal part of the excretory duct cells of the major salivary glands, whereas it was positive in the luminal membranes of both the initial part and the terminal part of the excretory duct cells of the minor salivary glands. These disparate distributions between the major and the minor salivary glands suggest different physiological excretions in the striated duct. P-gp may be physiologically involved in an important part of the transporter system, not only in the acinar serous cells and the striated duct cells, but also in the excretory duct cells in the salivary glands.

Increased oxidative stress in childhood atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease of unknown etiology. To examine the involvement of impaired homeostasis of oxygen/nitrogen radicals in childhood AD, we compared the levels of urinary 8-hydroxy-2'-deoxyguanosine (marker of oxidative stress), nitrite/nitrate (marker of nitric oxide synthesis) and selenium (marker of selenium store) in 27 children with AD to those of 25 healthy control children. Urinary 8-hydroxy-2'-deoxyguanosine was significantly higher and nitrite/nitrate levels were significantly lower in patients with AD than in the control. Urinary selenium levels were similar in both groups. Our findings suggest that impaired homeostasis of oxygen/nitrogen radicals and increased oxidative stress are involved in the pathophysiology of childhood AD, and indicate that suppression of oxidative stress might be a potentially useful strategy for the treatment of AD.

Evaluation of central nervous system involvement in nasal lymphomas

OBJECTIVES

To clarify the usefulness of evaluating central nervous system (CNS) involvement in patients with nasal lymphomas at the initial staging procedure, and of CNS prophylaxis for patients with clinical stage I/II.

PATIENTS AND METHODS

We retrospectively reviewed 43 patients with nasal lymphomas who had been treated from 1973 through 1999. The staging procedure included mainly computed tomography (CT), ultrasonography, gallium scintigraphy, upper gastrointestinal study, magnetic resonance (MR) imaging, and bone marrow biopsy. Forty-two patients received radiotherapy, and 25 patients received chemotherapy. All 38 patients with stage I/II were not subjected to CNS prophylaxis.

RESULTS

Four patients demonstrated CNS involvement at the staging procedure. MR imaging demonstrated the tumor had directly infiltrated the skull base in 3 patients, but CT demonstrated CNS infiltration in only one patient. In another patient, cerebrospinal fluid (CSF) cytologic analyses demonstrated CNS involvement, but MR imaging and CT did not. These 4 patients complained of frontonasal pain and/or cerebral nerve dysfunction. No patient with stage I/II developed CNS relapse.

CONCLUSIONS

MR imaging and CSF cytologic analyses should be performed at the initial staging of nasal lymphomas, especially in patients with frontonasal pain and/or cerebral nerve dysfunction. Patients with stage I/II might not need CNS prophylaxis.

Atherogenic lipoprotein changes in diabetic nephropathy

Cardiovascular risk is increased in patients with diabetic nephropathy. The aim of this study was to examine the relative impacts of albuminuria and renal failure, the two important features of diabetic nephropathy, on potentially atherogenic lipoprotein changes in this condition. The subjects were 160 non-diabetic healthy controls and a total of 200 type 2 diabetes patients with various degrees of nephropathy. The diabetic patients were divided into four groups by urinary albumin/creatinine ratio (U-ACR) and serum creatinine (S-Cr) levels: DM-1 (U-ACR< 30 mg/g, N=85), DM-2 (U-ACR=30-300 mg/g, N=48), DM-3 (U-ACR > 300 mg/g, N=29) and DM-4 (S-Cr>177 micromol/l or 2.0mg/dl, N=38). Lipids in very low (VLDL), intermediate (IDL), low (LDL), and high density (HDL) lipoproteins were measured following ultracentrifugation. VLDL-cholesterol (VLDL-C) was elevated (by 73-100%) in diabetic patients and it did not differ among the stages of nephropathy. IDL-C was higher as the nephropathy stage was advanced, and the elevation was significant in the DM-3 (by 75%) and DM-4 (by 131%) groups. LDL-C was not elevated in diabetic patients and was not different among the stages of nephropathy. Reduction of HDL-C was significant in DM-1, DM-2 and DM-3 (by 12-16%) and it was more exaggerated in DM-4 (by 35%). Multiple regression analyses indicated that elevated S-Cr, but not U-ACR, was an independent factor associated with raised IDL-C and lowered HDL-C in diabetic patients. These results indicate that diabetic patients with nephropathy show multiple lipoprotein changes, and that renal failure has greater impact than albuminuria on abnormalities in IDL and HDL. These lipoprotein alterations may contribute to an increased cardiovascular risk in diabetic nephropathy, especially in diabetic renal failure.

CD3 polymorphism in cynomolgus monkeys (Macaca fascicularis)

Cynomolgus monkeys were divided into two groups in terms of the reactivity of their lymphocytes with the FN18 monoclonal antibody, which is directed to the CD3 of rhesus monkeys. It was shown that 24 (12.2%) out of 196 monkeys did not have lymphocytes that reacted with the FN18, although T cells from those animals responded well to mitogenic stimulation. We have determined the nucleotide sequences of the CD3delta, CD3gamma, and CD3epsilon chains and found that two amino acids of the CD3epsilon chain of the FN18 non-reactive monkeys were different when compared with the FN18 reactive monkeys. Our results indicated that the CD3epsilon molecule of cynomolgus monkeys is polymorphic at the epitope level, which is recognized by the FN18 monoclonal antibody.

Identification and characterization of a transcriptional regulator for the lck proximal promoter

The lck gene encodes a protein-tyrosine kinase that plays a key role in signaling mediated through T cell receptor (TCR) and pre-TCR complexes. Transcription of the lck gene is regulated by two independent promoter elements: the proximal and distal promoters. Previous studies employing transgenic mice demonstrated that the sequence between -584 and -240 from the transcription start site in the mouse lck proximal promoter is required for its tissue-specific expression in the thymus. In this study, we demonstrate that a Krüppel-like zinc finger protein, mtbeta (BFCOL1, BERF-1, ZBP-89, ZNF148), previously cloned as a protein that binds to the CD3delta gene enhancer, binds to the -365 to -328 region of the lck proximal promoter. mtbeta is ubiquitously expressed in various cell lines and mouse tissues. Overexpressed mtbeta is more active in T-lineage cells than B-lineage cells for transactivating an artificial promoter consisting of the mtbeta binding site and a TATA box. Activity of the lck proximal promoter was significantly impaired by mutating the mtbeta binding site or by reducing mtbeta protein expression level by using antisense mRNA. Our results indicate that mtbeta activity is regulated in a tissue-specific manner and that mtbeta is a critical transactivator for the lck proximal promoter.

An in vitro assay reveals essential protein components for the "catch" state of invertebrate smooth muscle

"Catch," a state where some invertebrate muscles sustain high tension over long periods of time with little energy expenditure (low ATP hydrolysis rate) is similar to the "latch" state of vertebrate smooth muscles. Its induction and release involve Ca(2+)-dependent phosphatase and cAMP-dependent protein kinase, respectively. Molecular mechanisms for catch remain obscure. Here, we describe a quantitative microscopic in vitro assay reconstituting the catch state with proteins isolated from catch muscles. Thick filaments attached to glass coverslips and pretreated with approximately 10(-4) M free Ca(2+) and soluble muscle proteins bound fluorescently labeled native thin filaments tightly in catch at approximately 10(-8) M free Ca(2+) in the presence of MgATP. At approximately 10(-4) M free Ca(2+), the thin filaments moved at approximately 4 microm/s. Addition of cAMP and cAMP-dependent protein kinase at approximately 10(-8) M free Ca(2+) caused their release. Rabbit skeletal muscle F-actin filaments completely reproduced the results obtained with native thin filaments. Binding forces >500 pN/microm between thick and F-actin filaments were measured by glass microneedles, and were sufficient to explain catch tension in vivo. Synthetic filaments of purified myosin and twitchin bound F-actin in catch, showing that other components of native thick filaments such as paramyosin and catchin are not essential. The binding between synthetic thick filaments and F-actin filaments depended on phosphorylation of twitchin but not of myosin. Cosedimentation experiments showed that twitchin did not bind directly to F-actin in catch. These results show that catch is a direct actomyosin interaction regulated by twitchin phosphorylation.

An intron 4 gene polymorphism in endothelial cell nitric oxide synthase might modulate lipid metabolism in nondiabetic patients on hemodialysis

We investigated the relationship between endothelial constitutive nitric oxide synthase (ecNOS) gene polymorphism and lipid metabolism in patients with nondiabetic chronic renal failure on hemodialysis. Serum from 181 nondiabetic patients on hemodialysis were examined. A genomic DNA fragment was amplified by polymerase chain reaction (PCR) for determining the ecNOS genotype. The PCR products were designated as a and b alleles by electrophoresis. In hemodialysis patients, the frequency of the ecNOS4 for b/b, b/a and a/a genotype was 76.6, 22.8 and 0.6%, respectively. There was not significant difference in the levels of total cholesterol (TC), triglyceride (TG) and calculated low-density lipoprotein cholesterol (LDL-c) in sera between patients (aa and ba) with the a allele and patients (bb) without the a allele. On the other hand, the levels of serum high-density lipoprotein cholesterol (HDL-c) in patients with the a allele (51.9 +/- 3.33 mg/dl) were significantly higher than those in patients without the a allele (43.05 +/- 1.40 mg/dl) (p = 0.005). The frequency of patients with the a allele and low levels of serum HDL-c among patients with a long duration of dialysis (> or =10 years) was significantly lower than that in patients with short duration of dialysis (<10 years) (p = 0.05). It appears that an intron 4 gene polymorphism in ecNOS may modulate lipid metabolism in nondiabetic patients on hemodialysis and the a allele of ecNOS gene polymorphism may affect the prognosis of hemodialysis patients with low levels of serum HDL-c.

Expression of a newly defined tumor-rejection antigen SART3 in musculoskeletal tumors and induction of HLA class I-restricted cytotoxic T lymphocytes by SART3-derived peptides

We recently reported that a SART3 tumor-rejection antigen possessing tumor epitopes is capable of inducing HLA class 1-restricted and tumor-specific cytotoxic T lymphocytes in cancer patients. We studied the expression of the SART3 protein in musculoskeletal tumors to find a molecule for potential use in tumor-specific immunotherapy. The SART3 was detected at protein levels in 100% of the osteosarcoma cell lines (n = 20), in 50% of the musculoskeletal tumor tissue specimens (n = 32), and at notable levels in 67% of osteosarcoma tissues (n = 9) and malignant fibrous histiocytosis tissues (n = 9), respectively. SART3-derived peptides at positions 109-118 and 315-323 induced HLA-A24-restricted tumor-specific cytoxic T lymphocytes from peripheral blood mononuclear cells of patients with osteosarcoma or malignant fibrous histiocytosis. These peptide-induced cytotoxic T lymphocytes recognized HLA-A24+ SART3+ osteosarcoma cells but not HLA-A24 or SART3 cells. These results suggest that the SART3 protein and its derived peptides could be molecules appropriate for use in specific immunotherapies for approximately 60% of HLA-A24+ patients with osteosarcoma or malignant fibrous histiocytosis.

Samarium-153 for intravascular irradiation therapy with liquid-filled balloons to prevent restenosis: acute and long-term results in a hypercholesterolemic rabbit restenosis model

BACKGROUND

It has been shown that irradiation with either beta and gamma sources inhibit neointimal formation. Samarium-153 ((153)Sm) is an isotope with 0.8 MeV, subdivided in three different beta energies and 103 keV of gamma energy. This compound has been tested and used in humans for palliation of pain from bone metastases. The aim of the present study was to evaluate the feasibility and efficacy of brachytherapy with (153)Sm-filled balloon to inhibit neointimal formation in rabbits after balloon overstretch injury.

METHODS

Nineteen rabbits underwent balloon injury in their iliac arteries. In 12 animals (control), oversized balloons filled with saline solution were inflated up to 5 atm for a period of 5 min. In 7 rabbits, the same procedure was performed but using balloons filled with (153)Sm. In all cases, both iliac arteries were treated. The prescribed radiation dose was 15 Gy at 1 mm depth. After 30 days, the animals were sacrificed and their arterial segments were analyzed. Radiation exposure at the animal chest to the table and at a distance of 1 m from the table was measured.

RESULTS

Histopathologic analysis showed a striking reduction in the amount of neointima in the irradiated arteries compared with control vessels (0.36+/-0.21 vs. 1.07+/-0.56 mm(2), P<.01). The dose delivered to the animal chest was 21.5 mR/h, whereas only 1.9 mR/h was measured at the table and virtually no radiation could be detected at a distance of 1 m from the table.

CONCLUSIONS

Brachytherapy with (153)Sm was feasible with minimal personnel exposure radiation and effectively inhibited neointimal formation in this experimental model. These results warrant further experimental and clinical investigations.

B7-dependent T-cell costimulation in mice lacking CD28 and CTLA4

To examine whether B7 costimulation can be mediated by a molecule on T cells that is neither CD28 nor CTLA4, we generated mice lacking both of these receptors. CD28/CTLA4(-/-) mice resemble CD28(-/-) mice in having decreased expression of T-cell activation markers in vivo and decreased T-cell proliferation in vitro, as compared with wild-type mice. Using multiple approaches, we find B7-dependent costimulation in CD28/CTLA4(-/-) mice. The proliferation of CD28/CTLA4(-/-) T cells is inhibited by CTLA4-Ig and by the use of antigen-presenting cells lacking both B7-1 and B7-2. CD28/CTLA4(-/-) T-cell proliferation is increased by exposure to Chinese hamster ovary cells transfected with B7-1 or B7-2. Finally, administration of CTLA4-Ig to CD28/CTLA4(-/-) cardiac allograft recipients significantly prolongs graft survival. These data support the existence of an additional receptor for B7 molecules that is neither CD28 nor CTLA4.

Isolation and structures of haterumadioxins A and B, cytotoxic endoperoxides from the Okinawan sponge Plakortis lita

Cytotoxic endoperoxides, haterumadioxins A (1) and B (2), were isolated from the Okinawan sponge Plakortis lita. Their structures were determined by spectroscopic analysis. The absolute stereostructure of 1 was determined by degradation reactions and the modified Mosher's method. Haterumadioxins showed significant cytotoxicity against 38 human cancer cell lines.

Self-augmentation effect of male-specific products on sexually differentiated progesterone metabolism in adult male rat liver microsomes

It is well known that several 3-keto-4-ene steroids such as progesterone and testosterone are metabolized in a gender-specific or -predominant manner by adult rat liver microsomes. In the male, these steroids are primarily metabolized into two oxidized (16alpha-hydroxyl and 6beta-hydroxyl) products mainly by the respective, male-specific cytochrome P450 subforms, CYP2C11 and CYP3A2, while they are primarily metabolized into the 5alpha-reduced products by female-predominant 5alpha-reductase in the female. These sexually differentiated enzyme activities are largely regulated at the transcription level under endocrine control. In the present study, we show that unlabeled 16alpha-hydroxyprogesterone and 6beta-hydroxyprogesterone inhibited the 5alpha-reductive [(3)H]progesterone metabolism by adult male rat liver microsomes without significantly inhibiting the CYP2C11 and CYP3A2 activities producing themselves, whereas 3alpha-hydroxy-5alpha-pregnan-20-one and 5alpha-pregnane-3,20-dione not only stimulated the 5alpha-reductive metabolism producing themselves but also inhibited the male-specific oxidative metabolism. This finding compels us to propose a novel hypothesis that adult male rat liver microsomes may possess a self-augmentation system regulated by the male-specific products on sexually differentiated steroid metabolism, besides regulation by gene expressions of the related enzymes.

Recognition of the Lck tyrosine kinase as a tumor antigen by cytotoxic T lymphocytes of cancer patients with distant metastases

The Lck protein (p56(lck)), a src family tyrosine kinase that is essential for T cell development and function, is aberrantly expressed in metastatic colon cancers. p56(lck) seems to facilitate the malignant transformation of epithelial cells through initiation of anchorage-independent proliferation. We demonstrate that the lck gene encodes antigenic epitopes recognized by the HLA class I-restricted and tumor-specific CTL of metastatic cancer patients. Lck peptides augmented CTL activity in peripheral blood mononuclear cells (PBMC) of colon and other epithelial cancer patients with distant metastases, but not those without distant metastases. CTL precursors recognizing the Lck peptide were identified in freshly prepared PBMC of patients with distant metastases, and their frequency was significantly augmented by stimulation with the peptide. Thus, Lck peptides could be useful in developing a specific immunotherapy for cancer patients with distant metastases.

eae-negative attaching and effacing Escherichia coli from piglets with diarrhea

One hundred and ninety strains of Escherichia coli that were isolated from pigs with diarrhea in the state of São Paulo, Brazil, and that were negative for enterotoxins and cytotoxins were investigated. Strains which adhered to HeLa cells were examined for fluorescence actin staining (FAS), the ability to induce attaching and effacing (A/E) lesions on HEp-2 cells detectable by transmission electron microscopy and the presence of eae gene sequences detected by PCR. Intimin production was detected by western blot and serogrouping was performed. Forty-seven isolates adhered to HeLa cells in several patterns, but none adhered in a localized adherence pattern. However, seven of the 47 adherent strains were positive for the FAS reaction, although the reactions were usually weak or atypical. One FAS-negative and three FAS-positive strains, which were examined for their ability to induce A/E lesions, were all positive. Subsequently, testing of these strains for the eae gene showed that they all lacked this gene. These findings, along with earlier reports of eae-negative A/E E. coli, suggest that higher quantities of E. coli in this category might be detected if more reliance were placed on phenotypic tests rather than on gene detection tests alone.

Identification of SART3-derived peptides capable of inducing HLA-A2-restricted and tumor-specific CTLs in cancer patients with different HLA-A2 subtypes

We recently identified the SART3 antigen encoding shared tumor epitopes recognized by HLA-A2402-restricted and tumor-specific CTLs. Our study investigated whether the SART3 antigen encodes peptides recognized by the HLA-A2-restricted CTLs. The HLA-A2-restricted and tumor-specific CTL line recognized COS-7 cells co-transfected with the SART3 gene and either HLA-A0201, -A0206 or -A0207 cDNA but not those co-transfected with the SART3 gene and HLA-A2402 or -A2601 cDNA. The 2 SART3 peptides at positions 302 to 310 and 309 to 317 possessed the ability to induce HLA-A2-restricted and tumor-specific CTLs from peripheral blood mononuclear cells of cancer patients with various histological types and different HLA-A2 subtypes. Therefore, these 2 peptides could be useful for specific immunotherapy of a relatively large number of HLA-A2(+) cancer patients.

Tacrolimus (FK506) treatment of CD34+ hematopoietic progenitor cells promote the development of dendritic cells that drive CD4+ T cells toward Th2 responses

The macrolide lactone, tacrolimus (FK506), is utilized in bone marrow transplantation (BMT) to prevent graft-versus-host disease (GVHD). In the current study, we evaluated the ability of FK506 to modify the function of dendritic cells (DCs) derived from CD34+ hematopoietic progenitor cells (HPCs). Comparable to DCs obtained in the absence of FK506, DCs cultured in the presence of FK506 (FK-DCs) had higher expression of CD1a+ and formed a greater number of DC colonies. Despite the same expression of costimulatory molecules, FK-DCs displayed a reduced capacity to stimulate an allogeneic T cell response, and showed significantly lower interleukin (IL)-12 production. While normal DCs pulsed with the exogenous antigen, keyhole limpet hemocyanin (KLH) induced specific Th1-like interferon-gamma(IFN-gamma) producing CD4+ T cell line, FK-DCs induced Th2-like interleukin-4 (IL-4) producing CD4+ T cell line. These data demonstrate the ability of FK506 to induce Th2-promoting function in developing DCs.

A microfilament formation inhibitor, cytochalasin strongly enhances the low-affinity Fc epsilon receptor II (CD23) expression on the human monocyte-like cell line, U937

Enhancement of the low-affinity Fc epsilon receptor (CD23) expression by cytochalasin was analyzed on the human monocytelike cell line, U937. The CD23 expression on the U937 cells was enhanced at 24 hr after culture with cytochalasin B, D, or E, especially cytochalasin E having the most remarkable effect on it at the low concentration. This enhanced expression was found to be associated with a concomitant increase of a CD23 (about 45-kDa) protein on the U937 cells as assessed by Western blotting analysis. On the other hand, CD11a, CD18, CD31, CD49d, or CD54 was not markedly enhanced on the U937 cells by culture with cytochalasin E, although the mean fluorescence intensities (MFIs) of CD11a, CD18, and CD54 on U937 was partially up-regulated. Cell growth of U937 cultured with cytochalasin E was completely suppressed for 72 hr, but cell viability was sufficiently maintained (more than 95%). Soluble-formed CD23 (sCD23) also was released from the U937 cells at 24 to 72 hr after culture with cytochalasin E. In addition, the protein tyrosine kinase activity was detected in the U937 cells cultured with cytochalasin E for 24 hr using the enzyme immunoassay. Enhancement of the CD23 expression on the U937 cells at 24 to 72 hr cultured with cytochalasin E was sufficiently blocked by protein tyrosine kinase inhibitors herbimycin A and genistein, and a protein synthesis inhibitor, cychloheximide. On the other hand, protein kinase C inhibitors such as H-7 and H-8 had no effect on this CD23 expression. These results suggest that a mechanism underlying enhancement of the CD23 expression on the U937 cells cultured with cytochalasin E is mediated through tyrosine phosphorylation and protein synthesis.

Chlorella vulgaris culture supernatant (CVS) reduces psychological stress-induced apoptosis in thymocytes of mice

A glycoprotein prepared from Chlorella vulgaris culture supernatant (CVS) is a biological response modifier (BRM) which exhibits protective activities against tumor metastasis and 5-fluorouracil-induced immunosuppression. We here show that oral administration of CVS prevented significantly the apoptosis of thymocytes in mice undergoing psychological stress in a communication box. Mice were exposed to the emotional stress for 14 days by witnessing other mice being exposed to foot-shock. The numbers in thymocytes, especially CD4(+)CD8(+) population, were decreased significantly and apoptotic cells, as assessed by Annexin V expression, were reciprocally increased after the exposure to the psychological stress. C. vulgaris culture supernatant (CVS) administration significantly suppressed the increase in serum corticosterone level in the psychologically stressed mice. These results suggest that CVS prevents psychological stress and maintain homeostasis in the face of external environmental changes.

Production of eicosapentaenoic acid by a recombinant marine cyanobacterium, Synechococcus sp

The eicosapentaenoic acid (EPA) synthesis gene cluster from an EPA-producing bacterium, Shewanella sp. SCRC-2738, was cloned into a broad-host range vector, pJRD215, and then introduced into a marine cyanobacterium, Synechococcus sp. NKBG15041c, by conjugation. The transconjugant cyanobacteria produced 3.7 +/- 0.2% (2.24 +/- 0.13 mg/L) EPA (n-3) and 2.5 +/- 0.2% (1.49 +/- 0.06 mg/L) eicosatetraenoic acid (n-3) of the total fatty acids when the cells were cultured at 23 degrees C at a light intensity of 1,000-1,500 Lux. The EPA and eico-satetraenoic acid contents of the cells were increased to 4.6 +/- 0.6% (3.86 +/- 1.11 mg/L) and 4.7 +/- 0.3% (3.86 +/- 0.82 mg/L), and 7.5 +/- 0.3% (1.76 +/- 0.10 mg/L) and 5.1 +/- 0.2% (1.19 +/- 0.06 mg/L) when they were cultured at low temperature (18 degrees C) and at lower light intensity (40 Lux), respectively.

[Human tumor-rejection antigens and peptides from genes to clinical research]

One of the most significant advances in the field of modern tumor immunology is the identification of genes encoding tumor-rejection antigens that are recognized by human leukocyte antigen (HLA) class I-restricted and tumor-specific cytotoxic T lymphocytes (CTLs). Several peptides encoded by these genes are now under clinical trial as cancer vaccines, and major tumor regression has been observed in some melanoma patients. These results indicate that identification of the peptides capable of inducing CTLs may provide a new modality of cancer therapy. We investigated tumor-rejection antigens from epithelial cancers, and reported 7 genes encoding tumor-rejection antigens and peptides available for specific immunotherapy of HLA-A26 or -A24 patients with epithelial cancers. Furthermore, we identified more than 10 genes encoding tumor-rejection antigens and peptides available for specific immunotherapy of HLA-A2 patients with epithelial cancers. Therefore these new antigens and peptides could be applicable to the treatment of numerous epithelial cancer patients worldwide. Phase I clinical trials of cancer vaccine with these peptides for epithelial cancer patients are in progress at our university. Basic and clinical research will provide new insights for a better understanding of the molecular basis of T cell-mediated recognition of cancer cells and be important for the development of cancer vaccines.

Inhibition of smooth-muscle myosin-light-chain phosphatase by Ruthenium Red

Ruthenium Red (RuR) is widely used as an inhibitor of ryanodine receptor Ca(2+) release channels, but has additional effects such as the induction of Ca(2+) sensitization of contraction of permeabilized smooth muscles. To address the mechanism underlying this process, we examined the effects of RuR on contractility in permeabilized guinea-pig ileum and on the activity of myosin-light-chain phosphatase (MP). RuR increased the force at submaximal [Ca(2+)] (pCa 6.3) approx. 4-fold. This effect was not observed after thiophosphorylation of MP. RuR also seemed capable of preventing the thiophosphorylation of MP, suggesting a direct interaction of RuR with MP. Consistent with this possibility, smooth-muscle MP was inhibited by RuR in a concentration-dependent manner (IC(50) 23 microM). Exogenous calmodulin significantly increased RuR-induced contraction at pCa 6.3 but had little effect on contraction induced by microcystin at this [Ca(2+)]. Ca(2+)-independent contraction was induced by RuR (EC(50) 843 microM) and by microcystin (EC(50) 59 nM) but the maximal force induced by RuR was smaller than that induced by microcystin. The addition of 300 microM RuR enhanced the contraction induced by 30 nM microcystin but markedly decreased that induced by 1 microM microcystin. Such a dual action of RuR on microcystin-induced effects was not observed in experiments using purified MP. We conclude that the RuR-induced Ca(2+) sensitization of smooth-muscle contraction is due to the direct inhibition of MP by RuR.

A case of mixed connective tissue disease (MCTD) complicated with MPO-ANCA-related necrotizing glomerulonephritis

Renal diseases of mixed connective tissue disease (MCTD) are not unusual. Although most of them are SLE-like renal impairment with immune complex deposits, systemic sclerosis- (SSc) like renal impairments with intimal thickening of interlobular arteries or arterioles are also encountered. Several cases of SSc complicated with MPO-ANCA-related necrotizing glomerulonephritis (nGN) are reported. Here we report a case which developed MPO-ANCA-related nGN 16 years after the diagnosis of MCTD. She exhibited pauci-immune focal nGN and significantly high titer of MPO-ANCA. She was successfully treated with prednisolone and cyclophosphamide. We believe this is the first case in which MPO-ANCA-related nGN was demonstrated in a patient with MCTD.

[A case treated surgically through anterior axillary thoracotomy for recurrent right spontaneous pneumothorax after repeated video-assisted thoracoscopic surgery]

A 21-year-old male who had thoracoscopic surgery for right spontaneous pneumothorax was admitted to our hospital complaining of dyspnea due to the recurrence. There was no bulla in right apex but empysematous change in visceral pleura at re-thoracoscopic surgery. Two bulla in right S6 were removal using endo-stapler. Three years after the second thoracoscopic surgery, the recurrence of right pneumothorax was recognized. Chest CT revealed a new bulla in right apex. Therefore the third operation was carried out through anterior axillary thoracotomy. A new bulla was resected with endo-stapler and pleurodesis using argon laser was also applied to prevent of recurrence of pneumothorax. The patient is now doing well without recurrence 6 months after the third operation.

marY1, a member of the gypsy group of long terminal repeat retroelements from the ectomycorrhizal basidiomycete Tricholoma matsutake

We cloned an intact copy of a long terminal repeat retroelement designated marY1 from the ectomycorrhizal basidiomycete Tricholoma matsutake. The reverse transcriptase domain is found in T. matsutake and Tricholoma magnivelare worldwide. This finding suggests that retroelements associate with ectomycorrhizal basidiomycetes and may be useful as genetic markers for identification, phylogenetic analysis, and mutagenesis of this fungal group.

Treatment of hypoglossia-hypodactyly syndrome without extremeity anomalies

Three cases of hypoglossia-hypodactyly syndrome without limb deformities are reported. All exhibited different degrees of tongue hypoplasia, micrognathia, retrognathia with a very narrow space between the left and right halves of the mandible, constricted isthmus, and only one lower incisor. Bone lengthening for the midline mandibular hypoplasia and orthodontic treatment were performed in the three cases with satisfactory results.

Reduced ventricular response irregularity is associated with increased mortality in patients with chronic atrial fibrillation

BACKGROUND-Variations in the ventricular response interval (VRI) during atrial fibrillation (AF) may be reduced in patients with adverse clinical outcomes. The properties of VRI dynamics associated with prognosis remain undetermined. METHODS AND RESULTS-In 107 patients with chronic AF (age, 64+/-9 years), we analyzed a 24-hour ambulatory ECG for VRI variability (SD, SD of successive differences, and SD of 5-minute averages) and VRI irregularity (Shannon entropy of histogram, symbolic dynamics, and approximate entropy of beat-to-beat and minute-to-minute fluctuations [ApEn(b-b) and ApEn(m-m)]). During a follow-up period of 33+/-16 months, 18 patients died (17%), 9 from cardiac causes, 7 from fatal strokes, and 2 from malignancies. Reductions in all VRI variability and irregularity measures were associated with an increased risk for cardiac death but not for fatal stroke. A significant association with cardiac death was also found for ejection fraction (relative risk, 1.10; 95% confidence interval [CI], 1.04 to 1.17, per 1% decrement) and ischemic AF (relative risk, 6.52; 95% CI, 1.62 to 26. 3). After adjustment for these clinical variables, all irregularity measures except symbolic dynamics had predictive value (relative risks [95% CIs] per 1SD decrement: Shannon entropy of histogram, 2. 03 [1.14 to 3.61]; ApEn(b-b), 1.72 [1.14 to 2.60]; and ApEn(m-m), 1. 90 [1.03 to 3.52]); however, the predictive power of variability measures was no longer significant. When the patients were stratified with the 33rd and 67th percentile values of ApEn(b-b) (1. 83 and 1.94, respectively), the 5-year cardiac mortality rates for the upper, middle, and lower tertiles were 0%, 13%, and 43%, respectively (log-rank test, P=0.04). CONCLUSIONS-Reduced VRI irregularity in a 24-hour ambulatory ECG has an independent prognostic value for cardiac mortality during long-term follow-up in patients with chronic AF.

An FGF signal from endoderm and localized factors in the posterior-vegetal egg cytoplasm pattern the mesodermal tissues in the ascidian embryo

The major mesodermal tissues of ascidian larvae are muscle, notochord and mesenchyme. They are derived from the marginal zone surrounding the endoderm area in the vegetal hemisphere. Muscle fate is specified by localized ooplasmic determinants, whereas specification of notochord and mesenchyme requires inducing signals from endoderm at the 32-cell stage. In the present study, we demonstrated that all endoderm precursors were able to induce formation of notochord and mesenchyme cells in presumptive notochord and mesenchyme blastomeres, respectively, indicating that the type of tissue induced depends on differences in the responsiveness of the signal-receiving blastomeres. Basic fibroblast growth factor (bFGF), but not activin A, induced formation of mesenchyme cells as well as notochord cells. Treatment of mesenchyme-muscle precursors isolated from early 32-cell embryos with bFGF promoted mesenchyme fate and suppressed muscle fate, which is a default fate assigned by the posterior-vegetal cytoplasm (PVC) of the eggs. The sensitivity of the mesenchyme precursors to bFGF reached a maximum at the 32-cell stage, and the time required for effective induction of mesenchyme cells was only 10 minutes, features similar to those of notochord induction. These results support the idea that the distinct tissue types, notochord and mesenchyme, are induced by the same signaling molecule originating from endoderm precursors. We also demonstrated that the PVC causes the difference in the responsiveness of notochord and mesenchyme precursor blastomeres. Removal of the PVC resulted in loss of mesenchyme and in ectopic notochord formation. In contrast, transplantation of the PVC led to ectopic formation of mesenchyme cells and loss of notochord. Thus, in normal development, notochord is induced by an FGF-like signal in the anterior margin of the vegetal hemisphere, where PVC is absent, and mesenchyme is induced by an FGF-like signal in the posterior margin, where PVC is present. The whole picture of mesodermal patterning in ascidian embryos is now known. We also discuss the importance of FGF induced asymmetric divisions, of notochord and mesenchyme precursor blastomeres at the 64-cell stage.

The role of CD154-CD40 versus CD28-B7 costimulatory pathways in regulating allogeneic Th1 and Th2 responses in vivo

We used signal transducer and activator of transcription 4 (STAT4) and STAT6 gene knockout (-/-) mice as recipients of fully mismatched cardiac allografts to study the role of T-cell costimulatory pathways in regulating allogeneic T-helper 1 (Th1) versus Th2 responses in vivo. STAT4(-/-) mice have impaired Th1 responses, whereas STAT6(-/-) mice do not generate normal Th2 responses. Cardiac allografts from C57BL/6 mice were transplanted into normal wild-type (WT), STAT4(-/-), and STAT6(-/-) BALB/c recipients. STAT4(-/-) and STAT6(-/-) mice rejected their grafts with the same tempo as untreated WT recipients. CD28-B7 blockade by a single injection of CTLA4Ig induced long-term engraftment and donor-specific tolerance in all three groups of recipients. CD154 blockade by a single injection of MR1 was effective in prolonging allograft survival and inducing tolerance in STAT4(-/-) mice but was only marginally effective in STAT6(-/-) recipients and WT controls. In addition, a similar protocol of MR1 was ineffective in prolonging graft survival in CD28(-/-) BALB/c recipients, suggesting that the lack of efficacy seen in WT and STAT6(-/-) mice is not due to the presence of a functional CD28-B7 pathway. Furthermore, there was a similar differential effect of CD28-B7 versus CD154-CD40 blockade in inhibiting immune responses in animals immunized with ovalbumin and complete Freund's adjuvant. These novel data indicate that Th1 and Th2 cells are differentially regulated by CD28-B7 versus CD154-CD40 costimulation pathways in vivo and may have potential implications for the development of therapeutic strategies such as T-cell costimulatory blockade in humans.

Identification of a new endoplasmic reticulum-resident protein recognized by HLA-A24-restricted tumor-infiltrating lymphocytes of lung cancer

To help clarify the molecular basis of tumor immunology in lung cancer, we have investigated antigens recognized by HLA-A24-restricted CTLs established from T cells infiltrating into lung adenocarcinoma and report a new gene encoding tumor epitopes recognized by the CTLs. This gene was located on chromosome 4q31.22 and encoded an unreported endoplasmic reticulum-resident protein with 412 deduced amino acids. This protein had a molecular mass of 46 kDa and was expressed in the majority of malignant cells and tissues tested, with the exception of T-cell leukemia cells, but was not expressed in a panel of normal cells and tissues, except in those of the testis, placenta, and fetal liver. Two peptides at positions 13-20 and 75-84 were recognized by the CTLs and had an ability to induce HLA-A24-restricted and tumor-specific CTLs in peripheral blood mononuclear cells of lung cancer patients. Thus, these peptides might be appropriate molecules for use in the specific immunotherapy of HLA-A24+ patients with lung and other cancers.

Complementation of defective translesion synthesis and UV light sensitivity in xeroderma pigmentosum variant cells by human and mouse DNA polymerase eta

Defects in the human gene XPV result in the variant form of the genetic disease xeroderma pigmentosum (XP-V). XPV encodes DNA polymerase eta, a novel DNA polymerase that belongs to the UmuC/DinB/Rad30 superfamily. This polymerase catalyzes the efficient and accurate translesion synthesis of DNA past cis-syn cyclobutane di-thymine lesions. In this report we present the cDNA sequence and expression profiles of the mouse XPV gene and demonstrate its ability to complement defective DNA synthesis in XP-V cells. The mouse XPV protein shares 80.3% amino acid identity and 86.9% similarity with the human XPV protein. The recombinant mouse XPV protein corrected the inability of XP-V cell extracts to carry out DNA replication, by bypassing thymine dimers on template DNA. Transfection of the mouse or human XPV cDNA into human XP-V cells corrected UV sensitivity. Northern blot analysis revealed that the mouse XPV gene is expressed ubiquitously, but at a higher level in testis, liver, skin and thymus compared to other tissues. Although the mouse XPV gene was not induced by UV irradiation, its expression was elevated approximately 4-fold during cell proliferation. These results suggest that DNA polymerase eta plays a role in DNA replication, though the enzyme is not essential for viability.