Existence of an immunoglobulin G component of naturally occurring HLA class I antibodies that are not directed against self-antigens in human serum

We compared the frequency of immunoglobulin G (IgG) type of human leukocyte antigen (HLA) class I antibodies between patients with systemic lupus erythematosus (SLE) and healthy controls using a highly sensitive FlowPRA method. Sixteen of 130 normal healthy males and 2 of 10 normal females without a history of pregnancy (none had ever been transfused) possessed HLA class I antibodies. In SLE, male, but not female patients, showed a significant increase in the frequency of the antibodies compared with the corresponding controls. The antibodies did not appear to be involved in the development of SLE because of no substantial relationship to the incidence of cytopenia or SLE disease activity index score. Each individual had 1-31 types of HLA class I antibodies. Interestingly, HLA class I antibodies did not correspond to the individual's own HLA antigens. Eight of 32 types of HLA class I antigens detected were rare in the Japanese population. These results suggest that an IgG component of naturally occurring HLA class I antibodies exists in human serum and that these antibodies are not antibodies against self-antigens.

MITF-CM, a newly identified isoform of microphthalmia-associated transcription factor, is expressed in cultured mast cells

The microphthalmia-associated transcription factor (MITF) gene encodes a basic helix-loop-helix and leucin zipper protein. In this study, we identified a novel MITF isoform, MITF-CM, which possesses a unique amino terminus. Exon 1CM is located 84 kb upstream of the exon encoding the B1b domain. MITF-CM was expressed in the human mast cell line HMC-1, the human basophilic cell line KU812, and CB-derived mast cells cultured for 10 weeks as well as bone marrow mononuclear cells. Transient transfection of MITF-CM cDNA in COS-7 cells resulted in the expression of a 64-kDa protein, detected by Western blotting, and nuclear localization of the protein, detected by immunostaining. The transient cotransfection of a luciferase construct under the control of the tyrosinase promoter and MITF-CM cDNA increased luciferase activity threefold. In contrast, none of the MITF isoforms transactivated both the tryptase and chymase gene promoters, indicating differences in the gene transactivation system between humans and mice.

Suppression of the internal electric field effects in ZnO/Zn(0.7)Mg(0.3)O quantum wells by ion-implantation induced intermixing

Strong suppression of the effects caused by the internal electric field in ZnO/ZnMgO quantum wells following ion-implantation and rapid thermal annealing, is revealed by photoluminescence, time-resolved photoluminescence, and band structure calculations. The implantation and annealing induces Zn/Mg intermixing, resulting in graded quantum well interfaces. This reduces the quantum-confined Stark shift and increases electron-hole wavefunction overlap, which significantly reduces the exciton lifetime and increases the oscillator strength.

Clinical epidemiology of ciprofloxacin-resistant Proteus mirabilis isolated from urine samples of hospitalised patients

This study investigated the clinical characteristics of ciprofloxacin-resistant Proteus mirabilis isolates from urine samples associated with nosocomial infection or colonisation, and identified the risk-factors for ciprofloxacin resistance. Data for patients with ciprofloxacin-resistant P. mirabilis isolates (n=13) were compared with those for randomly selected patients with ciprofloxacin-susceptible P. mirabilis isolates (n=40) who were matched by temporal occurrence as control patients. The majority of ciprofloxacin-resistant P. mirabilis isolates were multiresistant, and ciprofloxacin resistance was associated significantly with previous use of fluoroquinolones and production of extended-spectrum beta-lactamases.

Nutraceutical strategy in aging: targeting heat shock protein and inflammatory profile through understanding interleukin-6 polymorphism

The aging process is paralleled by two- to fourfold increases in plasma/serum levels of inflammatory mediators, such as cytokines and acute-phase proteins. In this study we assessed the inflammatory profile and polymorphism of healthy elderly subjects and the influence of a nutraceutical supplement. Forty elderly, generally healthy subjects were recruited, divided into two matched groups, and given either a fermented papaya preparation 9 g/day by mouth or the same amount of placebo. Treatments were carried out in a cross-over manner with a 3-month supplementation period followed by a 6-week washout period between treatments. Ten healthy young subjects served as controls. Interleukin-6 (IL-6) promoter -174 G/C polymorphism genotype was determined together with blood levels for redox status, proinflammatory cytokines, high sensitivity C-reactive protein, and serum 70 kDa heat shock protein (Hsp70) concentrations. Tumor necrosis factor-alpha and IL-6 were higher in elderly subjects (P < 0.05 versus young controls). The concentration of Hsp70 inversely correlated with markers of inflammation in -174 G/C-negative subjects (r = 0.62, P < 0.05). Nutraceutical intervention normalized the inflammatory parameters (P < 0.05) with a rise of Hsp70 (P < 0.05). This suggests that healthy elderly individuals may have a proinflammatory profile playing as a downregulating factor for inducible Hsp70, particularly if -174 G/C-negative. A nutraceutical intervention seems able to beneficially modulate such a phenomenon.

Ginkgo biloba extract EGb 761 attenuates hippocampal neuronal loss and cognitive dysfunction resulting from chronic restraint stress in ovariectomized rats

We have recently found that a combination of ovariectomy (OVX) and chronic restraint stress causes cognitive dysfunction and reduces hippocampal CA3 neurons in female rats and that estrogen replacement suppresses the OVX/stress-induced behavioral and morphological changes. In this study, we examined the effect of Ginkgo biloba extract (EGb 761), a popular herbal supplement, on the cognitive dysfunction and neuromorphological change in OVX/stress-subjected rats. Female Fisher 344 rats were randomly divided into three groups: vehicle-treated OVX, EGb 761 (50 mg/kg) -treated OVX and vehicle-treated sham-operated control groups. Two months after ovariectomy, all animals received restraint stress for 21 days (6 h/day), and were then subjected to a novel object recognition test followed by morphological examination by Nissl staining. EGb 761 was orally administered once daily until the behavioral analysis was done. Treatment with EGb 761 improved memory impairment and neuronal loss of hippocampus in the OVX/stress-subjected group in the same ways as 17beta-estradiol. On the other hand, EGb 761 did not affect the loss of bone mineral density and increase in body weight after OVX, although 17beta-estradiol attenuated them. These results have important implications for neuroprotective and cognition enhancing effects of EGb 761 in postmenopausal women and suggest that the effects are mediated by a different mechanism from estrogen.

Alpha1-adrenoceptors are required for normal male sexual function

BACKGROUND AND PURPOSE

Alpha(1)-adrenoceptor antagonists are extensively used in the treatment of hypertension and lower urinary tract symptoms associated with benign prostatic hyperplasia. Among the side effects, ejaculatory dysfunction occurs more frequently with drugs that are relatively selective for alpha(1A)-adrenoceptors compared with other drugs of this class. This suggests that alpha(1A)-adrenoceptors may contribute to ejaculation. However, this has not been studied at the molecular level.

EXPERIMENTAL APPROACH

The physiological contribution of each alpha(1)-adrenoceptor subtype was characterized using alpha(1)-adrenoceptor subtype-selective knockout (KO) mice (alpha(1A)-, alpha(1B)- and alpha(1D)-AR KO mice) since the subtype-specific drugs available are only moderately selective. We analysed the role of alpha(1)-adrenoceptors in the blood pressure and vascular response as well as ejaculation by determining these variables in alpha(1)-adrenoceptor subtype-selective KO mice and in mice with all their alpha(1)-adrenoceptor subtypes deleted (alpha(1)-AR triple-KO mice).

KEY RESULTS

The pregnancy rate was reduced by 50% in alpha(1A)-adrenoceptor KO mice, and this reduction was dramatically enhanced in alpha(1)-adrenoceptor triple-KO mice. Contractile tension of the vas deferens in response to noradrenaline was markedly decreased in alpha(1A)-adrenoceptor KO mice, and this contraction was completely abolished in alpha(1)-adrenoceptor triple-KO mice. This attenuation of contractility was also observed in the electrically stimulated vas deferens.

CONCLUSIONS AND IMPLICATIONS

These results demonstrate that alpha(1)-adrenoceptors, particularly alpha(1A)-adrenoceptors, are required for normal contractility of the vas deferens and consequent sperm ejaculation as well as having a function in fertility.

Initial Experience with a Novel Low-Dose Micro-CT System

PURPOSE

Investigation of the hardware and image characteristics of a novel micro-CT system and evaluation of its potential to image animals and tissue samples.

MATERIALS AND METHODS

The scanner was characterized by phantom studies regarding image homogeneity, CT number stability, soft-tissue contrast, spatial resolution and X-ray dose. The phantoms used were specially designed to evaluate the imaging of mice and rats. Scans of hearts with coronary stents were performed and the tissue morphology and vascularization of tumor-bearing rodents were studied with dynamic contrast-enhanced (DCE) CT.

RESULTS

The CT numbers of the acrylic phantoms were reproducible with a 4 HU deviation. The inter-pixel deviation was low but depended on the scan mode. The correlation coefficient between CT number and iodine concentration (0 - 6000 HU) was 0.99. Single wires, lumen and endo-luminal plaques of heart stents were distinguishable. The density-time courses were reliably recorded and made it possible to distinguish the tumor and muscle tissue in DCE micro-CT scans

CONCLUSION

The novel micro-CT scanner is suitable for studying tissue densities and contrast agent kinetics.

Methicillin-resistant Staphylococcus aureus infection after living-donor liver transplantation in adults

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) infection frequently complicates the postoperative course in deceased-donor liver transplantation. The incidence and risk factors of MRSA infection after Living-donor Liver transplantation (LDLT), however, are unclear.

METHODS

We retrospectively reviewed the data from 242 adult patients who underwent LDLT at the University of Tokyo Hospital. The microbiologic and medical records of the patients from admission to 3 months after LDLT were reviewed. Uni- and multivariate analyses were performed to identify the independent risk factors for postoperative MRSA infection.

RESULTS

Postoperative MRSA infection occurred in 25 of 242 patients by median postoperative day 23. Preoperative MRSA colonization, preoperative use of antimicrobials, operation time (> or =16 h), and postoperative apheresis independently predicted postoperative MRSA infection.

CONCLUSION

Surveillance culture should be checked periodically after admission to identify patients at high risk for MRSA infection and to administer appropriate antimicrobials for perioperative infection. Postoperative apheresis, suggesting postoperative liver dysfunction, predisposed patients to MRSA infection.

Adult-onset acute tubulointerstitial nephritis and uveitis with Fanconi syndromeCase report and review of the literature

We report a case of tubulointerstitial nephritis and uveitis (TINU syndrome) with full type Fanconi syndrome. A 32-year-old woman presented with fatigue, anorexia and weight loss. Laboratory findings showed anemia, polyclonal hypergammaglobulinemia and moderate renal dysfunction. Tubular function abnormalities were normoglycemic glucosuria, panaminoaciduria, phosphaturia and kaliuresis leading to hypokalemia. Renal tubular acidosis and hypouricemia were also evident. Serum antistreptolysin O titer was high. Ocular symptoms (bilateral anterior uveitis) emerged soon after admission. Renal biopsy showed diffuse tubulointerstitial infiltration by lymphocytes and plasma cells without granuloma. Treatment with systemic steroids was given and renal function, and ocular symptom returned to normal with 3 months. Although tubular abnormalities involving TINU syndrome has already been reported, the disease associated with full type Fanconi syndrome has rarely been seen, and systemic steroid may be beneficial in reducing the development of tubulointerstitial injury.

Successful treatment of disseminated Nocardia farcinica infection in a living-donor liver transplantation recipient

Nocardiosis is a serious infection with high mortality. We report a case of subcutaneous and neural lesions due to Nocardia farcinica infection after living-donor liver transplantation. The neural lesion was cured with antibiotics without drainage.

17beta-estradiol attenuates hippocampal neuronal loss and cognitive dysfunction induced by chronic restraint stress in ovariectomized rats

Several lines of evidence suggest that hormonal changes after menopause may play an important role in the incidence of cognitive dysfunction, and also in the development of Alzheimer's disease. In this study, we investigated the effect of estrogen on cognitive function in rats under different stress environment. Female rats were divided into four groups: two groups were ovariectomized (OVX) and two were sham-operated. One group each of OVX and sham rats was kept in a normal environment, and the other groups were assigned to a daily restraint stress (6 h/day) for 21 days from 2 months after the operation. Following the stress period, subjects were tested for performance in novel object recognition test and then used for morphological and neurochemical analyses. The OVX plus stress (OVX/stress) group showed a significant impairment of recognition of novel objects, compared with the other groups. The OVX/stress group also showed a marked decrease in the number of pyramidal cells of the CA3 region and levels of brain-derived neurotrophic factor mRNA in the hippocampus. We further examined the effect of estrogen against cognitive dysfunction and hippocampal changes of OVX/stress rats. Vehicle or 17beta-estradiol (E2) at 20 microg/day was s.c. administered to OVX/stress rats from 2 days before the stress period to the end of behavioral analysis through an implantable osmotic pump. Chronic E2 treatment decreased stress response and improved the cognitive and morphological impairments relative to vehicle group. These data have important implications for cognition enhancing effect of estrogen treatment in postmenopausal women.

Sarcoidosis of the tongue: a case report

A case of sarcoidosis involving the tongue is described in a 48-year-old Japanese man. A definite diagnosis of sarcoidosis was made for the clinical lesion and pathological examinations. Sarcoidosis is a multisystem granulomatous disease that may affect any organ. Sarcoidosis of the tongue is particularly rare.

Tight regulation of transgene expression by tetracycline-dependent activator and repressor in brain

Methods to temporally and spatially regulate gene mutations will provide a powerful strategy to investigate gene function in the brain. To develop these methods, we have established a tightly regulated system for transgene expression in the forebrain using both a tetracycline (Tc)-dependent transcription activator (rtTA) and a repressor (TetR-Kruppel-associated box). In this system, the repressor binds to the Tc-responsive element (TRE) in the absence of doxycycline (Dox), leading to the repression of leaky activation of TRE-mediated transcription caused by weak binding of rtTA to TRE. Upon Dox administration, only the activator binds to TRE and activates transcription. We tested this system in cultured cells by bicistronically expressing both the regulators using an internal ribosome entry site (IRES). In COS-1, HeLa and SHSY5Y cells, leaky transcription activation led by rtTA in the absence of Dox was repressed without decreasing the level of activated transcription in the presence of Dox. Using this system, transgenic mice were produced that express both the regulators using IRES in the forebrain under the control of the alphaCaMKII promoter and were bred with transgenic mice carrying the TRE-dependent reporter transgene. In reverse transcription-polymerase chain reaction and in situ hybridization analyses of the forebrain in adult double transgenic mice, the treatment of Dox induces reporter mRNA expression, which was not detected before the treatment and after the withdraw of Dox following the treatment. These results indicate that this system allows the tight regulation of transgene expression in a Dox-dependent fashion in the forebrain and will be useful in investigating gene function in the brain.