Caffeine inhibits exercise-induced increase in tryptophan hydroxylase expression in dorsal and median raphe of Sprague-Dawley rats

Effect of caffeine on the expression of tryptophan hydroxylase (TPH), rate limiting enzyme of serotonin synthesis, in dorsal and median raphe was investigated via immunohistochemistry. In exercise groups, Sprague-Dawley rats were put on treadmill running for 30 min per day for 6 consecutive days. On the seventh day, animals of control-with-caffeine group were injected subcutaneously with 4 mg/kg caffeine, while control-without-caffeine group were injected with 0.9% NaCl, sacrificed 2 h later. Exercise-with-caffeine group and exercise-without-caffeine group were injected with caffeine and NaCl, respectively; all-out time was determined 1 h after injection, and then sacrificed. Caffeine increased all-out time in exercised rats, and inhibited the exercise-induced elevation in TPH expression. The suppressive effect of caffeine on TPH expression in exercised rats can be suggested as one possible ergogenic mechanism of caffeine.

Lack of the burst firing of thalamocortical relay neurons and resistance to absence seizures in mice lacking alpha(1G) T-type Ca(2+) channels

T-type Ca(2+) currents have been proposed to be involved in the genesis of spike-and-wave discharges, a sign of absence seizures, but direct evidence in vivo to support this hypothesis has been lacking. To address this question, we generated a null mutation of the alpha(1G) subunit of T-type Ca(2+) channels. The thalamocortical relay neurons of the alpha(1G)-deficient mice lacked the burst mode firing of action potentials, whereas they showed the normal pattern of tonic mode firing. The alpha(1G)-deficient thalamus was specifically resistant to the generation of spike-and-wave discharges in response to GABA(B) receptor activation. Thus, the modulation of the intrinsic firing pattern mediated by alpha(1G) T-type Ca(2+) channels plays a critical role in the genesis of absence seizures in the thalamocortical pathway.

C-terminal fragment of amyloid precursor protein induces astrocytosis

One of the pathophysiological features of Alzheimer's disease is astrocytosis around senile plaques. Reactive astrocytes may produce proinflammatory mediators, nitric oxide, and subsequent reactive oxygen intermediates such as peroxynitrites. In the present study, we investigated the possible role of the C-terminal fragment of amyloid precursor protein (CT-APP), which is another constituent of amyloid senile plaque and an abnormal product of APP metabolism, as an inducer of astrocytosis. We report that 100 nM recombinant C-terminal 105 amino acid fragment (CT105) of APP induced astrocytosis morphologically and immunologically. CT105 exposure resulted in activation of mitogen-activated protein kinase (MAPK) pathways as well as transcription factor NF-kappaB. Pretreatment with PD098059 and/or SB203580 decreased nitric oxide (NO) production and nuclear factor-kappa B (NF-kappaB) activation. But inhibitors of NF-kappaB activation did not affect MAPKs activation whereas they abolished NO production and attenuated astrocytosis. Furthermore, conditioned media derived from CT105-treated astrocytes enhanced neurotoxicity and pretreatment with NO and peroxynitrite scavengers attenuated its toxicity. These suggest that CT-APP may participate in Alzheimer's pathogenesis through MAPKs- and NF-kappaB-dependent astrocytosis and iNOS induction.

Dehydroepiandrosterone replacement in addison's disease

Addison's disease is a rare endocrine disorder which can be life-threatening. It can also interfere with the normal development of adrenarche, resulting in the absence of pubic and axillary hair growth. We report a case of satisfactory restoration of adrenarche through DHEA administered in conjunction with the standard glucocortisone and fluorocortisone replacement.

Investigating hepatitis C virus heterogeneity in a high prevalence setting using heteroduplex tracking analysis

Hepatitis C virus (HCV) infection is very common among chronic hemodialysis patients. In the past, blood transfusion appeared to be the primary risk factor; however evidence of nosocomial HCV transmission in the hemodialysis setting has recently been reported. This report describes a molecular investigation of HCV isolates obtained from a population of 670 patients attending six different Seattle-King County based hemodialysis centers in order to identify potential common source infections. 733 serum specimens were collected from hemodialysis patients in 1992 and 1996, and were tested for HCV antibodies and RNA. Overall, 115 of 670 (17%) patients were positive for HCV RNA, and thus were considered actively infected by HCV. HCV genotype was determined in all cases by restriction fragment length polymorphism, and 93 patients were found to be infected by HCV genotype 1. HCV envelope genes were amplified from the 93 patients with genotype 1 infection, and were studied in further detail by heteroduplex tracking analysis (HTA) using genotype 1a and 1b specific probes derived from the envelope 1 (E1) and envelope 2 (E2) genes. Genetic relatedness between pairs of HCV envelope genes was estimated by calculating the degree of gel shift relative to homoduplex controls. Nucleotide sequencing and phylogenetic analysis was used to confirm genetic relatedness detected by HTA. When HTA was performed using the E1 gene probe, 12 apparently related infections were detected; 10 of 12 (83%) of these infections were confirmed as truly related using the gold standard method of nucleotide sequencing plus phylogenetic analysis. Using an E2 gene probe, 24 infections were apparently related, but only six (25%) were confirmed by sequencing. As a control, 41 envelope genes, which were unrelated by HTA, were sequenced; 0 of 41 (0%) were truly related. In summary, HTA provides a rapid and effective molecular technique for screening HCV genetic relatedness in population-based studies, and should prove valuable in future studies of HCV molecular epidemiology.

The protective role of HSP90 against 3-hydroxykynurenine-induced neuronal apoptosis

3-hydroxykynurenine (3HK), an endogenous metabolite of tryptophan in the kynurenine pathway, is a potential neurotoxin in several neurodegenerative disorders. Stabilizing protein structure, heat shock proteins (HSPs) have diverse roles as molecular chaperones to mediate stress tolerance. In the present study, we investigated the possible protective role of HSPs against 3HK induced neuronal cell death. Here we report that 3HK induced in a dose- and time-dependent manner neuronal cell death in neuroblastoma SK-N-SH cells. The cell death showed characteristic apoptotic features such as cell shrinkage, plasma membrane blebbing, chromatin condensation, and nuclear condensation and fragmentation. Furthermore, SK-N-SN cells were protected from 3HK induced cytotoxicity by prior elevation of HSPs expression. Our results show that the protective effect was abolished by HSP90 anti-sense oligonucleotides while not by HSP27 and HSP70 anti-sense oligonucleotides. Also, our result shows that HSP90 effectively inhibits caspases activities leading to the apoptosis. These results suggest that 3HK induces apoptosis in neuroblastoma SK-N-SN cells and that HSP90 is major contributing protein component of protection against 3HK induced apoptosis.

Purification and characterization of a novel extracellular protease from Bacillus cereus KCTC 3674

Bacillus cereus KCTC 3674 excretes several kinds of extracellular proteases into the growth medium. Two proteases with molecular masses of approximately 36-kDa and 38-kDa, as shown by SDS-PAGE, were purified from the culture broth. The 38-kDa protease was purified from B. cereus cultivated at 37 degrees C, and the 36-kDa protease was obtained from the B. cereus cultivated at 20 degrees C. The 38-kDa protease was identified as an extracellular neutral (metallo-) protease and was further characterized. The 36-kDa protease was shown to be a novel enzyme based on its N-terminal amino acid sequence, its identification as a metallo-enzyme that was strongly inhibited by EDTA and o-phenanthroline, its hemolysis properties, and its optimal pH and temperature for activity of 8.0 and 70 degrees C, respectively.

A case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota

The Sturge-Weber syndrome consists of a unilateral port-wine hemangioma of the skin along the trigeminal distribution and is accompanied by an ipsilateral leptomeningeal angioma. Glaucoma is present in approximately half of the cases. The Nevus of Ota is a melanocytic pigmentary disorder, most commonly involving the area innervated by the trigeminal nerve. Elevated intraocular pressure, with or without glaucomatous damage, is observed in 10% of the cases. We report the first case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota in Korea.

Hybrid organic/inorganic reverse osmosis (RO) membrane for bactericidal anti-fouling. 1. Preparation and characterization of TiO2 nanoparticle self-assembled aromatic polyamide thin-film-composite (TFC) membrane

Hybrid organic/inorganic reverse osmosis (RO) membranes composed of aromatic polyamide thin films underneath titanium dioxide (TiO2) nanosized particles have been fabricated by a self-assembly process, aiming at breakthrough of biofouling problems. First, positively charged particles of the colloidal TiO2 were synthesized by a sol-gel process, and the diameter of the resulting particles in acidic aqueous solution was estimated to be approximately 2 nm by analyzing the UV-visible absorption characteristics with a quantum mechanical model developed by Brus. Transmission electron microscopy (TEM) further confirmed the formation of the quantum-sized TiO2 particles (approximately 10 nm or less). The TiO2 particles appeared to exist in the crystallographic form of anatase as observed with the X-ray diffraction (XRD) pattern in comparison with those of commercial 100% rutile and commercial 70:30% anatase-to-rutile mixture. The hybrid thin-film-composite (TFC) aromatic polyamide membranes were prepared by self-assembly of the TiO2 nanoparticles on the polymer chains with COOH groups along the surface. They showed improved RO performance in which the water flux even increased, though slightly. Field-emission scanning electron microscopy (FESEM) exhibited the TiO2 nanoparticles well adsorbed onto the surface. X-ray photoelectron spectroscopy (XPS) demonstrated quantitatively that a considerable amount of the adsorbed particles were tightly self-assembled at the expense of the initial loss of those that were loosely bound, and became stabilized even after exposure to the various washing and harsh RO operating conditions. The antibacterial fouling potential of the TiO2 hybrid membrane was examined and verified by measuring the viable numbers and determining the survival ratios of the Escherichia coli (E. coli) as a model bacterium, both with and without UV light illumination. The photocatalytic bactericidal efficiency was remarkably higher for the TiO2 hybrid membrane under UV illumination, compared to that of the same membrane in darkness, as well as those for the neat membranes under either light condition.

Thermolysis of tert-butyl phenylperacetates: delicate control of the rates through contributions from translational and rotational entropy

The first-order rate constants (k(Y)) at several temperatures in CDCl(3) were measured for thermal decompositions of YC(6)H(4)CH(2)CO(3)C(CH(3))(3) with Y being p-OCH(3), p-OPh, p-CH(3), p-Ph, p-H, p-Cl, m-Cl, and p-NO(2). The relative rates (k(Y)/k(H)) exhibit excellent rho(+)/sigma(+) Hammett correlations with rho(+) < 0, indicating a polar TS. Activation parameters (DeltaH()(Y) and DeltaS()(Y)) and their differential terms (DeltaDeltaH()(Y)(-)(H) and DeltaDeltaS()(Y)(-)(H)) were obtained from the Eyring plot. Differential activation terms (DeltaDeltaH()(Y)(-)(H) and DeltaDeltaS()(Y)(-)(H)) disclose an isokinetic relation with p-CH(3), p-Ph, p-H, p-Cl, and m-Cl (isokinetic temp, 230 K). However, p-OCH(3), and p-OPh show negative deviations, and a positive deviation occurs with p-NO(2). Plot of DeltaDeltaH()(Y)(-)(H) vs sigma(+) exhibits a good linear relation (r = 0.95) with a slope (alpha(1) = -3.34). A better linear correlation (r = 0.97) and steeper slope (alpha(2) = -5.22) were observed for TDeltaDeltaS()(Y)(-)(H) vs sigma(+). Negatively larger slope (alpha(2) = -5.22) may point to entropy control of rates. Differential activation parameters (DeltaDeltaH()(Y)(-)(H) and DeltaDeltaS()(Y)(-)(H)) reflect variations of activation process. Differential activation entropies (DeltaDeltaS()(Y)(-)(H)) are discussed in terms of contributions of translational and rotational entropies. Similar deviation behaviors of p-OCH(3), p-OPh, and p-NO(2) were again observed for the both plots. p-NO(2) can strongly destabilize the cationic site of the polar TS but serves an eminent spin delocalizer for the homolytic TS.

The future of human ovarian cryopreservation and transplantation: fertility and beyond

OBJECTIVE

To review the current progress in ovarian cryopreservation and transplantation and to discuss the obstacles with the clinical application of this technique.

DESIGN

The literature on ovarian cryopreservation and transplantation was reviewed to facilitate understanding and predict future directions. The studies related to this topic were identified through MEDLINE and other bibliographic databases, focusing on the most recent developments.

CONCLUSION(S)

The experimental evidence for low-temperature storage of ovarian tissue is encouraging. Although restoration of fertility with cryopreserved ovarian grafts has been successful in various animals, there are uncertainties about the optimum use of stored ovarian tissue in humans. Autotransplantation appears to be promising, but the potential risk of transmitting malignant cells in women with cancer is of great concern. The maturation of primordial follicles with xenotransplantation is encouraging, but the efficacy and the safety of this method need further investigation. Furthermore, the quality of oocytes that have been matured in a host animal is unknown. The development of in vitro culture systems for oocyte maturation is still in its infancy. There are many issues to be resolved in ovarian transplantation before the full clinical use of this emerging technique. Most of all, there is an urgent need to optimize the freeze/thaw procedure and to find the means to protect grafts from ischemia-reperfusion injury. Nevertheless, ovarian transplantation should prove to be clinically useful for women at risk for premature ovarian failure.

Effects of stimulation of AMP-activated protein kinase on insulin-like growth factor 1- and epidermal growth factor-dependent extracellular signal-regulated kinase pathway

AMP-activated protein kinase (AMPK) is tightly regulated by the cellular AMP:ATP ratio and plays a central role in the regulation of energy homeostasis. Previously, AMPK was reported to phosphorylate serine 621 of Raf-1 in vitro. In the present study, we investigated a possible role of AMPK in extracellular signal-regulated kinase (Erk) cascades, using 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR), a cell-permeable activator of AMPK and antisense RNA experiments. Activation of AMPK by AICAR in NIH-3T3 cells resulted in drastic inhibitions of Ras, Raf-1, and Erk activation induced by insulin-like growth factor 1 (IGF-1). Expression of an antisense RNA for the AMPK catalytic subunit decreased the AMPK activity and significantly diminished the AICAR effect on IGF-1-induced Ras activation and the subsequent Erk activation, indicating that its effect is indeed mediated by AMPK. Phosphorylation of Raf-1 serine 621, however, was not involved in AMPK-mediated inhibition of Erk cascades. In contrast to IGF-1, AICAR did not block epidermal growth factor (EGF)-dependent Raf-1 and Erk activation, but our results demonstrated that multiple Raf-1 upstream pathways induced by EGF were differentially affected by AICAR: inhibition of Ras activation and simultaneous induction of Ras-independent Raf activation. The activities of IGF-1 and EGF receptor were not affected by AICAR. Taken together, our results suggest that AMPK differentially regulate Erk cascades by inhibiting Ras activation or stimulating the Ras-independent pathway in response to the varying energy status of the cell.

Anaphylaxis caused by the new ant, Pachycondyla chinensis: demonstration of specific IgE and IgE-binding components

BACKGROUND

There have been no reports dealing with the pathogenic mechanism and IgE-binding components in patients with anaphylaxis caused by a sting from Pachycondyla chinensis.

OBJECTIVES

This study was conducted to observe the clinical features of patients with P chinensis -induced anaphylaxis. The roles of specific (s) IgE and sIgG4 antibodies were evaluated, and IgE-binding components were identified.

METHODS

Seven patients with P chinensis -induced anaphylaxis and 15 unexposed control subjects were enrolled. P chinensis ants were collected at the patients' homes, and venom was prepared as P chinensis extract. Five patients complained of bee venom-induced anaphylaxis and had positive sIgE levels to yellow jacket venom, wasp venom, or both as well. Serum sIgE and sIgG4 were detected by means of ELISA. To identify IgE-binding components within P chinensis extracts, 12% SDS-PAGE with immunoblot analysis was applied.

RESULTS

All patients had positive skin prick test responses to P chinensis antigen and positive sIgE levels. Five (71%) patients had positive sIgG4 levels. Eight IgE-binding components (58, 46, 3l, 29, 27, 25, 22, and 12 kd) were noted, and the component at 12 kd was the most frequently found allergen (85%). IgE ELISA inhibition tests were performed on 2 groups of sera: one from patients with anaphylaxis induced by both P chinensis and bee venom (group A) and the other from patients with anaphylaxis induced by P chinensis venom alone without bee venom allergy (group B). ELISA inhibition tests with serum from group A showed significant inhibitions with addition of P chinensis extract, partial inhibitions with yellow jacket antigen, and minimal inhibitions with wasp or imported fire ant antigens. However, ELISA inhibition tests with serum from group B showed significant inhibitions with P chinensis antigen but no inhibition with wasp, yellow jacket, or imported fire ant antigens.

CONCLUSIONS

IgE-mediated reactions contributed to the development of P chinensis -induced anaphylaxis. Eight IgE-binding components and one major allergen (12 kd) were identified. Further studies will be needed to clarify the role of sIgG4 and to identify allergenic relationships with major bee and wasp allergens.

Role of phospholipase C-gamma1 in insulin-like growth factor I-induced muscle differentiation of H9c2 cardiac myoblasts

Insulin-like growth factor-I (IGF-I) regulates muscle differentiation through phosphatidylinositol 3-kinase (PI 3-kinase). Also it was recently reported that PI 3-kinase is involved in the activation of phospholipase C-gamma1 (PLC-gamma1). We investigated whether PLC-gamma1 therefore plays a role in IGF-I-induced muscle differentiation using H9c2 rat cardiac myoblasts as a model. IGF-I was able to activate PLC-gamma1 via both PI 3-kinase-dependent and tyrosine phosphorylation-dependent mechanisms in this model. However, PI 3-kinase appeared to play a more important role than tyrosine phosphorylation in IGF-I activation of PLC-gamma1. In addition, PLC-gamma1 activation was independent of Akt/protein kinase B (Akt/PKB). Importantly, PLC-gamma1 was involved in IGF-I-induced muscle differentiation in parallel with Akt/PKB. Taken together, these results suggest that IGF-I regulation of muscle differentiation is dependent on the activation of PLC-gamma1 and Akt/PKB, both of which are downstream mediators of PI 3-kinase.

Clinical and immunologic changes after allergen immunotherapy with Hop Japanese pollen

BACKGROUND AND OBJECTIVE

Hop Japanese (Hop J) pollen has been reported as one of the major causative pollen allergens in the autumn season. There have been no published data regarding the clinical and immunologic effects of Hop J pollen immunotherapy in sensitized patients. In this study, we evaluated clinical and immunologic effects of Hop J immunotherapy.

PATIENTS AND METHODS

Pollens were collected in our area, and "Depo-Hop J" was prepared in the laboratory of Allergopharma (Reinbek, Germany). Fifteen asthmatic patients who had Hop J immunotherapy for > 1 year were enrolled. Their clinical parameters, such as asthma symptom scores, were monitored. Skin reactivity to Hop J and degree of airway hyperresponsiveness to methacholine were measured before and 1 year after the immunotherapy. Sera were collected before the immunotherapy, at the end of initial therapy, and 1 year after the therapy. Serum total IgE levels were compared by radioimmunoassay. Serum-specific IgE, IgG1, and IgG4 levels to Hop J were compared by ELISA. To evaluate the changes of cellular mechanisms, soluble CD30 (sCD30), soluble interleukin (IL)-2 receptor (sIL-2R), soluble CD23 (sCD23), and IL-10 levels were measured by ELISA.

RESULTS

Specific IgG1 and IgG4 levels began to increase at the end of the initial therapy (P < 0.05) with significant decreases in symptom scores (P < 0.05), whereas total and specific IgE levels showed variable responses during the immunotherapy with no statistical significance (P > 0.05). Serum sIL-2R and sCD30 levels decreased significantly (P < 0.05) 1 year after immunotherapy. No significant changes were noted in sCD23, IL-10, skin reactivity to Hop J, or airway responsiveness to methacholine (P > 0.05).

CONCLUSIONS

We are certain that Hop J allergen immunotherapy, if carried out properly according to suitable indications, can favorably influence asthma. Thus, an increase in specific IgG4 and IgG1 antibodies and reduction of a possible Th2 lymphocyte marker (sCD30) may be associated with symptomatic improvements.

Occupational asthma and rhinitis caused by multiple herbal agents in a pharmacist

BACKGROUND

Herb agents have been widely used for centuries in the Orient and they have been cultivated throughout Asia. There have been a few cases of occupational allergy caused by herb materials. We report a case of occupational asthma and rhinitis caused by six herb materials in a pharmacist working at a pharmacy.

OBJECTIVE

We sought the role of immediate hypersensitivity in herbal agent-induced asthma in a pharmacist.

METHODS AND RESULTS

The patient had strong positive responses on skin prick test to extracts of six herb materials: Chunkung (Cnidii rhizoma), Banha (Pinellia ternata), Sanyak (Dioscorea radix), Kangwhal (Ostericum koreanum), Danggui (Angelica radix), and Kunkang (Zingiberis rhizoma). Bronchoprovocation tests showed an early asthmatic response to Danggui extract. Serum specific IgE antibodies to Chunkung, Banha, and Sanyak were detected by ELISA with no specific IgE bindings to Kangwhal, Danggui, and Kunkang extracts. Twelve percent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and IgE immunoblotting revealed one IgE binding component (60 kD) within Chunkung extract, two (10, 25 kD) in Banha, and four (33, 34, 65, 98 kD) in Sanyak. Basophil histamine release test revealed that Danggui extract could release a greater amount of histamine from basophils in the patient than in a healthy control.

CONCLUSIONS

Chunkung, Banha, and Sanyak may induce IgE-mediated bronchoconstriction in an exposed worker, and Danggui can cause bronchoconstriction by direct histamine-releasing effect from mast cells in a sensitized patient.

Expression of CC chemokine receptor 3 on human keratinocytes in vivo and in vitro--upregulation by RANTES

CC chemokines and their ligands, CC chemokine receptors (CCRs), play an important role in the process of inflammation such as trafficking and activating inflammatory cells. CCR3 is known to be a ligand for CC chemokines such as RANTES, eotaxin and monocyte-chemotactic protein-3 (MCP-3). In this study we examined the expression of CCR3 in cultured normal human keratinocytes (KCs). CCR3 protein and mRNA expressions were detected in cultured normal KCs by flow cytometric (FACS) analysis and reverse-transcription-polymerase chain reaction (RT-PCR) analysis. FACS analysis demonstrated that CCR3 expression on KCs was significantly upregulated when the cells were cultured with RANTES, but not with eotaxin, IL-4 or interferon-gamma. RT-PCR analysis revealed that CCR3 mRNA was detectable in normal KCs. We also examined the immunoreactivity of CCR3 in normal skin and inflammatory skin lesions. CCR3 was detected weakly in epidermis of normal skin, while strong immunoreactivity for CCR3 was seen in epidermis of inflammatory skin lesions such as atopic dermatitis. These results suggest that CCR3 is constitutively expressed on KCs and is involved in inflammatory modulation. RANTES may regulate the function of KCs through CCR3.

Generation of replication-defective helper-free vectors based on simian immunodeficiency virus

A systematic study on generating simian immunodeficiency virus (SIV)-based vectors was carried out. The goal was to generate helper-free, replication-defective SIVmac-based vectors at high titers. The general approach was to cotransfect into human 293T cells a plasmid carrying the vector construct along with two helper plasmids that together expressed the SIVmac virion proteins. Initial vectors carried the bacterial beta-galactosidase gene (beta-gal). These vectors had a technical difficulty: "pseudotransduction" of beta-gal protein produced during the 293T cell transfections. As a result, infection of cultures with these vector stocks also resulted in passive transfer into, and X-gal staining of, cells that had not actually been infected by the vector. A second generation of vectors expressing the enhanced jellyfish green fluorescence protein (EGFP) was not subject to this artifact. A systematic study of the SIVmac-based EGFP vectors was carried out. Helper-free vector stocks were obtained when helper plasmids lacking the SIVmac packaging signals were used. By employing envelope helper plasmids derived from different SIVmac isolates, it was possible to generate SIVmac-based vectors pseudotyped with envelope proteins of different cell tropism. Optimization of vector and helper plasmid structures, transfection conditions, and infection procedures ultimately yielded vector titers in excess of 10(6)/ml.

A case of hypothermia combined with systemic lupus erythematosus

Systemic lupus erythematosus(SLE) is a prototypic autoimmune disease affecting various organ systems. Hypothermia is a rare manifestation of SLE. We experienced a case of SLE combined with hypothermia. A 36-year-old woman, who had been diagnosed as SLE 3 days before admission, admitted complaining of mental confusion. After admission, her body temperature, initially 36.1 degrees C, became 32.6 degrees C. Her core body temperature was less than 35.0 degrees C. Despite of warming with heating lamp and blankets, her core temperature did not reach 35.0 degrees C during 18 hours. Ten days later, her temperature exceeded 36.0 degrees C.

Computed tomographic and anatomical analysis of the basal lamellas in the ethmoid sinus

OBJECTIVES

To investigate the exact anatomical structure of the lamellas in the ethmoid sinus by computed tomography (CT) and anatomical analysis.

STUDY DESIGN

Cadaver dissections and CT scans were used to compare lamellar structures and their radiological images.

METHODS

Anatomical microdissection of 100 midsagittal sections from adult cadaver head specimens were examined and compared with those of sagittal CT scans at 1-mm intervals.

RESULTS

The posteroinferior end of the uncinate process attaching to the inferior turbinate divided the fontanelle into the anterior and posterior portions in the majority of cases. The basal lamellas of the bulla ethmoidalis were subdivided into three major types. The posteroinferior portion of its basal lamella was connected to the lower horizontal portion of the third basal lamella in all cases. The anterior indentation of the third lamella was identified in nine cases, but there was no indentation in the posterior direction. The basal lamella of the superior turbinate was attached to the skull base superiorly either separately or fused to the third lamella, and its posteroinferior portion was attached to the lowest portion of the anterior wall of the sphenoid sinus. The supreme turbinate existed in 50 cases; however, its basal lamella was identified in only 15 cases.

CONCLUSIONS

Our results indicate that the lamellas of the ethmoid sinus have relatively uniform patterns, although there is variability in shape. It is hoped that this study will provide surgeons with a more detailed structure of the basal lamellas for better surgical results and lower complication rates.

Long-term results with St. Jude Medical and CarboMedics prosthetic heart valves

BACKGROUND AND AIM OF THE STUDY

The clinical evaluation and comparison of St. Jude Medical (SJM) and CarboMedics (CM) prosthetic heart valves implanted between 1988 and 1997 is presented.

METHODS

In total, 648 SJM valves were implanted in 641 patients, and 601 CM valves in 591 patients. There were 684 mitral valve replacements, 256 aortic valve replacements, 252 mitral and aortic (double) valve replacements, 16 triple valve replacements, and 41 other tricuspid-related valve replacements. Total follow up was 98%. The overall incidence of valve-related events was compared before and after establishment of a 'valve clinic' in 1993.

RESULTS

The overall hospital mortality was 3.4%; late mortality was 8.2%. The five- and ten-year survival for all patients was 92.1% and 86.2%, respectively. There were 31 episodes of thromboembolism in 27 patients (including valve thrombosis in three), 21 episodes of bleeding events in 20 patients, and 18 re-replacements of implanted valves. No structural valve deterioration was observed. Freedom from thromboembolism was 97.8% at five years and 96.3% at ten years; freedom from bleeding episodes was 98.1% and 97.6%, respectively. In terms of hospital and late mortality, and incidence of thromboembolism, hemorrhagic episodes and structural valve failure, no statistically significant differences were found between the SJM and CarboMedics patient groups. Freedom from thromboembolism was 96.7% at five years before initiation of an intensive follow up program, and 99.0% thereafter (p = 0.031). In contrast, freedom from bleeding episodes fell from 99.3% to 96.1% during the same time period (p = 0.0004).

CONCLUSION

Both the SJM and CM prosthetic heart valves performed well in our study, and no discernible differences in clinical performance of the two valves were detected. The intensive follow up program resulted in a reduced incidence of thromboembolism, but an increased number of bleeding complications. An optimum anticoagulation regimen to manage these two conflicting problems has yet to be elucidated.

Use of helper-free replication-defective simian immunodeficiency virus-based vectors to study macrophage and T tropism: evidence for distinct levels of restriction in primary macrophages and a T-cell line

Cell tropism of human and simian immunodeficiency viruses (HIV and SIV, respectively) is governed in part by interactions between the viral envelope protein and the cellular receptors. However, there is evidence that envelope-host cell interactions also affect postentry steps in viral replication. We used a helper-free replication-defective SIV macaque (SIVmac)-based retroviral vector carrying the enhanced jellyfish green fluorescent protein inserted into the nef region (V1EGFP) to examine SIV tropism in a single cycle of infection. Vector stocks containing envelope proteins from three different SIVmac clones, namely, SIVmac239 (T-lymphocyte tropic [T-tropic]), SIVmac316 (macrophage tropic [M-tropic]), and SIVmac1A11 (dualtropic), were tested. SIVmac239 replicates efficiently in many human T-cell lines, but it does not efficiently infect primary rhesus macrophages. Conversely, SIVmac316 efficiently infects primary macrophages, but it does not replicate in Molt4-Clone8 (M4C8) T cells. SIVmac1A11 replicates efficiently in both cell types. When primary macrophages were infected with V1EGFP pseudotyped by SIVmac316 or SIVmac1A11 envelopes, the infection was substantially (ca. 200- to 300-fold) more efficient than for the SIVmac239 pseudotype. Thus, in primary macrophages, a major component of M versus T tropism involves relatively early events in the infection cycle. Quantitative PCR studies indicated that synthesis and transport of vector DNA into the nucleus were similar for macrophages infected with the clone 239 and 316 pseudotypes, suggesting that the restriction for SIVmac239 infection is after reverse transcription and nuclear import of viral DNA. When the same vector pseudotypes were used to infect M4C8 cells, they all showed approximately equivalent infectivities, even though replication-competent SIVmac316 does not continue to replicate in these cells. Therefore, in M4C8 cells, restriction involves a late step in the infection cycle (after proviral integration and expression). Thus, depending on the cell type infected, envelope-dependent cell interactions that govern SIV M and T tropism may involve different steps in infection.

Effects of left atrial compliance on left atrial pressure in pure mitral stenosis

In mitral stenosis (MS), left atrial (LA) pressure is commonly elevated because of increased LA afterload. There is a wide spectrum of LA pressure in patients with MS, however, despite a similar mitral valve orifice area. LA compliance is an important determinant of both cardiovascular performance and pathological physiology. Few data are available, however, regarding the effects of LA compliance on LA pressure. We hypothesized that LA pressure may be higher in patients with decreased LA compliance. We analyzed the right heart and transseptal catheterization data in 47 patients (41 female, mean age 40 +/- 10 years) with pure MS and sinus rhythm. The magnitude of LA a and v waves was measured from transseptal catheterization. Fick's method was used to determine cardiac output. LA compliance was calculated by dividing the systolic rise in LA pressure (DeltaP(LA) = P(LA(v)) - P(LA(x))) into the stroke volume. LA size, mitral valve area (MVA), mean diastolic pressure gradient (MG), left ventricular (LV) end-diastolic and end-systolic dimensions were obtained by using two-dimensional and Doppler echocardiography. Multiple regression analysis was performed to identify independent factors determining LA pressure. The mean MVA was 0.95 +/- 0.22 cm(2). MG and LA dimension were 11.2 +/- 5.2 mm Hg and 50.6 +/- 5.2 mm, respectively. The mean LA pressure and cardiac output obtained by cardiac catheterization were 23.4 +/- 8.4 mm Hg and 4.3 +/- 1.5 L/min, respectively. The calculated LA compliance was 4.9 +/- 2.8 cm(3)/mm Hg. Univariate analysis showed that factors associated with increased LA pressure were smaller MVA (r = -0.33, P < 0.05), higher MG (r = 0.69, P < 0.01) and lower LA compliance (r = -0.55, P < 0.01); among them, MG (beta coefficient 0.59, SE 0.19, P < 0.01) and LA compliance (beta coefficient -0.26, standard error 0.34, P < 0.05) were the strongest predictors of LA pressure. In conclusion, LA compliance, along with MG that reflects the severity of MS, is an important contributing factor determining LA pressure in patients with pure MS and sinus rhythm.

Diverse profiles of specific IgE response to toluene diisocyanate (TDI)-human serum albumin conjugate in TDI-induced asthma patients

The prevalence studies on specific IgE to toluene diisocyanate (TDI)-human serum albumin (HSA) conjugate in TDI-induced asthma have shown variable results. In this study, we attempted to compare specific IgE bindings to TDI-HSA conjugate and its specificity using 3 different conjugates. Sera were collected from 20 TDI-induced asthma and 10 controls. Specific IgE were measured by ELISA using three TDI-HSA conjugates; two from Carnegie Mellon (CM; 98 and 99 CM conjugates) and one from Ajou University. To evaluate specificity and cross-reactivity, ELISA inhibition tests were applied. Positive and negative predictive values between Ajou conjugate and 98 CM conjugate were 75% and 100%. Those between Ajou and 99 CM were 100% and 93.8%. One patient showed an isolated positive response to the Ajou with negative responses to the other two conjugates. ELISA inhibition test using this patient's serum revealed the significant inhibitions by the Ajou and minimal inhibitions by the others. On the other hand, another patient showed an isolated positive response to 99 CM with negative responses to the others, and ELISA inhibition test showed significant inhibition by 99 CM with minimal inhibitions by the others. These results suggest that specific IgE bindings to a new antigenic determinant of TDI-HSA conjugate can be heterogeneous and differ from one individual to another.

Insulin-like growth factor-1 protects H9c2 cardiac myoblasts from oxidative stress-induced apoptosis via phosphatidylinositol 3-kinase and extracellular signal-regulated kinase pathways

Oxidative stress plays a critical role in cardiac injuries during ischemia/reperfusion. Insulin-like growth factor-1 (IGF-1) promotes cell survival in a number of cell types, but the effect of IGF-1 on the oxidative stress has not been elucidated in cardiac muscle cells. Therefore, we examined the role of IGF-1 signaling pathway in cell survival against H2O2-induced apoptosis in H9c2 cardiac myoblasts. H2O2 treatment induced apoptosis in H9c2 cells, and pretreatment of cells with IGF-1 suppressed apoptotic cell death. The antiapoptotic effect of IGF-1 was blocked by LY294002 (an inhibitor of phosphatidylinositol 3-kinase) and by PD98059 (an inhibitor of extracellular signal-regulated kinase (ERK)). The protective effect of IGF-1 was also blocked by rapamycin (an inhibitor of p70 S6 kinase). Furthermore, H9c2 cells stably transfected with constitutively active PI 3-kinase (H9c2-p110*) and Akt (H9c2-Gag-Akt) constructs were more resistant to H2O2 cytotoxicity than control cells. Although H2O2 activates both p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), IGF-1 inhibited only JNK activation. Activated PI 3-kinase (H9c2-p110*) and pretreatment of cells with IGF-1 down-regulated Bax protein levels compared to control cells. Taken together, our results suggest that IGF-1 transmits a survival signal against oxidative stress-induced apoptosis in H9c2 cells via PI 3-kinase and ERK-dependent pathways and the protective effect of IGF-1 is associated with the inhibition of JNK activation and Bax expression.

The Na+ -Ca2+ exchanger is essential for embryonic heart development in mice

The cardiac Na+ -Ca2+ exchanger 1 (NCX1) is thought to be the major calcium extrusion mechanism and to play an important role in the regulation of intracellular calcium in the heart. The Na+ -Ca2+ exchanger is particularly abundant in the heart, although it is found in a variety of other tissues. To investigate the role of NCX1, we have generated NCX1-deficient mice. Mice heterozygous for the NCX1 mutation showed no discernable phenotype, grew normally, and were fertile; however, no viable homozygote was observed among 175 offspring obtained from intercrosses of heterozygotes. All the homozygous mutant mice died in utero before E10.5. Morphological analysis indicated that homozygotes of NCX1 mutation at E9.5 died with an underdeveloped heart with a dilated pericardium. Microscopic analysis of these embryos showed myocardial cell loss due to apoptosis. The apoptosis was first observed in E8.5 mutant heart. Areas outside the heart appeared normal in the mutant embryos at E8.5. In contrast, at E9.0, various regions of mutant embryos showed extensive cell loss. These results suggest that mutant embryos die owing to cardiac abnormalities caused by apoptotic cell loss, indicating that NCX1 is essential for normal development of the heart.

Alteration of substrate specificity of valine dehydrogenase from Streptomyces albus

The catabolism of branched chain amino acids, especially valine, appears to play an important role in furnishing building blocks for macrolide and polyether antibiotic biosyntheses. To determine the active site residues of ValDH, we previously cloned, partially characterized, and identified the active site (lysine) of Streptomyces albus ValDH. Here we report further characterization of S. albus ValDH. The molecular weight of S. albus ValDH was determined to be 38 kDa by SDS-PAGE and 67 kDa by gel filtration chromatography indicating that the enzyme is composed of two identical subunits. Optimal pHs were 10.5 and 8.0 for dehydrogenase activity with valine and for reductive amination activity with alpha-ketoisovaleric acid, respectively. Several chemical reagents, which modify amino-acid side chains, inhibited the enzyme activity. To examine the role played by the residue for enzyme specificity, we constructed mutant ValDH by substituting alanine for glycine at position 124 by site-directed mutagenesis. This residue was chosen because it has been considered to be important for substrate discrimination by phenylalanine dehydrogenase (PheDH) and leucine dehydrogenase (LeuDH). The Ala-124-Gly mutant enzyme displayed lower activities toward aliphatic amino acids, but higher activities toward L-phenylalanine, L-tyrosine, and L-methionine compared to the wild type enzyme suggesting that Ala-124 is involved in substrate binding in S. albus ValDH.

Presence of circulating autoantibodies against bronchial epithelia cell in patients with nonatopic asthma

Allergic response to common environmental agents has been regarded as a main pathogenetic mechanism of bronchial asthma. However, allergic sensitization (atopy) can not be detected in a siginificant number of adult asthmatic patients. The etiology of nonatopic asthma has not yet been defined. To evaluate the possible involvement of autoimmune response against bronchial mucosa in the pathogenesis of nonatopic asthma, we performed indirect immunofluorescence staining of fresh frozen human bronchial mucosa tissue using serum samples from patients with atopic and nonatopic asthma, healthy controls, and patients with systemic lupus erythematosus. On immunostaining, circulating IgG autoantibodies against bronchial mucosa were detected in 2 (9.1%) of 22 patients with nonatopic asthma and in none of 22 patients with atopic asthma and of 22 healthy controls. IgG autoantibodies from the two patients with nonatopic asthma predominantly stained the cytoplasmic membrane of basal cells in bronchial epithelium. Serum samples from 10 patients with systemic lupus erythematosus immunostained the nucleus of epithelial cells in whole layer of bronchial epithelium. This study showed the presence of circulating IgG autoantibodies against the bronchial epithelial cell in a small portion of patients with nonatopic asthma. Further studies may be necessary to evaluate the possible involvement of autoimmune mechanism in the pathogenesis of nonatopic asthma.

beta-Chitin-based wound dressing containing silver sulfurdiazine

Physical and biological properties of some wound dressing materials based on beta-chitin were studied. Water vapor transmission rates (WVTR), oxygen permeabilities and biodegradation kinetics were examined for film-type samples. WVTR of samples was in the range 2400-2800 g/m2/day. However, oxygen permeabilities of the samples were relatively low. To improve oxygen permeabilities, porous sponge-type wound dressing materials were prepared. In addition, these sponge-type samples contained antimicrobial agents, silver sulfadiazine (AgSD), in order to prevent bacteria infection on a wound surface. Anti-microbacterial tests on agar plate were carried out to confirm the bactericidal capacity of present materials. These materials impregnating AgSD had the complete bactericidal capacity against pseudomonas aeruginosa up to 7 days. Finally, a wound healing effect of beta-chitin-based semi-interpenetrating polymer networks was evaluated from the animal test using the wistar rat in vivo. Histological studies confirm the proliferation of fibroblasts in the wound bed and a distinct reduction in infectious cells.

Expression of MUC5AC mRNA in the goblet cells of human nasal mucosa

OBJECTIVES/HYPOTHESIS

Mucus hypersecretion is a common feature in chronic sinusitis with polyps. Because mucus hypersecretion is commonly accompanied by goblet cell hyperplasia, it is important to identify which mucin gene mRNAs are expressed in the goblet cells of the surface epithelium in the human airway. This study aims to investigate the pattern of expression of MUC5AC messenger RNA (mRNA) in the goblet cells of human nasal mucosa.

METHODS

Six nasal polyps, five inferior turbinate mucosa specimens, and three normal-appearing mucosa specimens of the posterior ethmoid sinus were obtained. Each of the specimens was cut into 10-microm-thick serial frozen sections, and in situ hybridization of MUC5AC mRNA was performed with an oligonucleotide probe. Alcian blue (pH 2.5)-periodic acid-Schiff (AB-PAS) staining was performed on the serial sections.

RESULTS

In human nasal polyps, MUC5AC mRNA was expressed in the cytoplasm of most of the goblet cells. However, in the inferior turbinate, MUC5AC mRNA was expressed in only some of the goblet cells. On the contrary, in the normal-appearing mucosa of the posterior ethmoid sinus, MUC5AC mRNA was barely expressed in the goblet cells. Furthermore, MUC5AC mRNA was mainly expressed in some of the PAS-positive goblet cells.

CONCLUSIONS

Only a portion of the goblet cells in the human nasal mucosa expressed MUC5AC mRNA. This result suggests that surface goblet cells might have other mucin genes, in addition to MUC2 and MUC5AC.

Hypersensitivity pneumonitis caused by Fusarium napiforme in a home environment

BACKGROUND

We report a case of hypersensitivity pneumonitis (HP) in a 17-year-old male student caused by Fusarium napiforme found in his home environment.

METHODS

The patient was diagnosed according to history, chest radiograph, spirometry, high-resolution chest CT, and transbronchial lung biopsy. To identify the causative agent, cultured aeromolds were collected by the open-plate method. From the main fungi cultured, fungal antigens were prepared, and immunoblot analysis with the patient's serum and each fungal antigen was performed.

RESULTS

Five fungal species were isolated from the patient's home. Immunoblotting analysis with the patient's serum demonstrated more than 10 IgG-binding fractions to F. napiforme extract only, while little binding was noted with the other fungal antigens.

CONCLUSIONS

We should be aware that HP may be caused by F. napiforme in the home environment.

Malignant melanoma of the sinonasal cavity: explanation of magnetic resonance signal intensities with histopathologic characteristics

PURPOSE

To evaluate the magnetic resonance (MR) findings of malignant melanoma of the sinonasal cavity and compare these findings with those of the histopathological examination.

MATERIALS AND METHODS

The MR images of 11 patients with malignant melanoma of the sinonasal cavity were retrospectively reviewed. Ten patients had primary malignant melanoma of the sinonasal cavity and one had a local recurrence. The imaging findings were evaluated with special attention given to the signal intensity of the tumor, internal characteristics, and growth pattern on MR. Signal intensity and enhancement patterns of the tumors were compared with the histopathological findings.

RESULTS

On T1-weighted image, 6 tumors were hyperintense (5 melanotic and one amelanotic melanoma), and 5 tumors were isointense or hypointense (4 amelanotic and one melanotic). On T2-weighted images, 2 amelanotic tumors showed hyperintensity, and 5 melanotic tumors showed hypointensity. Four tumors (one melanotic and 3 amelanotic) were isointense. Four of the 7 tumors with hyperintensity on T1-weighted images showed patchy, higher-signal intensity areas. In 3 of them, patchy areas of a higher degree of pigmentation were found on histopathological examination. There were multiple linear dark signal intensities on T2-weighted images and/or linear-enhancing areas on enhanced T1-weighted images within the masses in 5 of the 11 patients. These findings could be explained as intratumoral vessels in 4 tumors and fibrous septa in one tumor on histopathological examinations.

CONCLUSION

Malignant melanoma of the sinonasal cavity shows characteristic MR signal intensity, which is mainly attributable to the degree and distribution of melanin pigmentation, and partly attributable to hemorrhage within the mass. The linear, low-signal intensity on T2-weighted images or enhanced lines are intratumoral vessels or fibrous septa.

No significant correlation exists between core promoter mutations, viral replication, and liver damage in chronic hepatitis B infection

Hepatitis B virus (HBV) core promoter mutants have been proposed to contribute to severe liver damage by increasing viral loads, but this has not yet been clearly shown. To examine the effects of core promoter mutants on viral load and liver damage, we first developed a polymerase chain reaction (PCR)-based semiquantitative HBV DNA detection method with a high sensitivity (able to detect as low as 10(3) molecules/mL). Then we cloned 12 predominant core promoter mutants from 41 chronic hepatitis B patients. The in vitro promoter and replication activities of these mutants were similar to those of wild-type virus. However, viral load was highly variable, and this was dependent on individual patients rather than mutant type. In addition, there was no mutant type that showed any unique correlation with alanine transaminase (ALT) levels. Viral load was not significantly correlated with ALT level in both cross-sectional and longitudinal studies. Quantitation of HBV levels also revealed no clear correlation between hepatitis B e antigen (HBeAg) status and viral load. Taken together, these results indicated that the replication activity of core promoter mutants has little effect on viral load, and that viral load does not correlate with the severity of liver damage or with HBeAg status.

Vitamin E and probucol reduce urinary lipophilic aldehydes and renal enlargement in streptozotocin-induced diabetic rats

Diabetes mellitus is characterized by complications affecting several organs, including the kidney. Lipid peroxidation increases in diabetes and has been implicated in the pathogenesis of diabetic complications. In this study, we examined the ability of two antioxidants, vitamin E and probucol, to reduce lipid peroxidation in vivo and renal hypertrophy, an early stage of diabetic nephropathy, in rats. Animals were divided into four groups: non-diabetic, diabetic, diabetic treated with vitamin E, and diabetic treated with probucol. Animals were given antioxidants by intraperitoneal injection after induction of diabetes by streptozotocin injection. After 7 wk, lipid peroxidation in vivo was measured by analyzing urinary excretion of lipophilic aldehydes and related carbonyl compounds (LACC) as 2,4-dinitrophenylhydrazones by high-performance liquid chromatography. A number of urinary lipophilic nonpolar and polar aldehydes and related carbonyl compounds were identified, almost all of which increased in diabetes. Antioxidant treatment resulted in significantly decreased excretion of urinary LACC excretion. Antioxidant treatment of diabetic rats reduced renal hypertrophy. There was a high correlation between kidney weight and urinary LACC. Since LACC are accepted markers of lipid peroxidation, these results indicate that antioxidants can reduce the elevated lipid peroxidation of diabetes and may slow the onset of diabetic nephropathy.

The structural basis of DNA target discrimination by papillomavirus E2 proteins

The papillomavirus E2 proteins regulate the transcription of all papillomavirus genes and are necessary for viral DNA replication. Disruption of the E2 gene is commonly associated with malignancy in cervical carcinoma, indicating that E2 has a role in regulating tumor progression. Although the E2 proteins from all characterized papillomaviruses bind specifically to the same 12-base pair DNA sequence, the cancer-associated human papillomavirus E2 proteins display a unique ability to detect DNA flexibility and intrinsic curvature. To understand the structural basis for this phenomenon, we have determined the crystal structures of the human papillomavirus-18 E2 DNA-binding domain and its complexes with high and low affinity binding sites. The E2 protein is a dimeric beta-barrel and the E2-DNA interaction is accompanied by a large deformation of the DNA as it conforms to the E2 surface. DNA conformation and E2-DNA contacts are similar in both high and low affinity complexes. The differences in affinity correlate with the flexibility of the DNA sequence. Preferences of E2 proteins from different papillomavirus strains for flexible or prevent DNA targets correlate with the distribution of positive charge on their DNA interaction surfaces, suggesting a role for electrostatic forces in the recognition of DNA deformability.

Salivary gland choristoma of the anterior chest wall

Salivary gland choristoma (heterotopic salivary gland tissue) is a rare condition that occurs at various locations within the head and neck. Diagnostic criteria and embryogenesis of this entity remain unclear. Presented herein is the first reported case of salivary gland choristoma on the anterior chest wall. Surgical treatment is recommended.

Phosphatidylinositol 3-kinase stimulates muscle differentiation by activating p38 mitogen-activated protein kinase

The activation of both phosphatidylinositol 3-kinase (PI3-kinase) and p38 mitogen-activated protein kinase (p38 MAPK) is required for muscle differentiation. However, it is not known whether the signals from these two kinases interact during this process. In this work, we have investigated this using H9c2 cardiac myoblasts. The p38 MAPK-specific inhibitor SB203580 blocked muscle differentiation and suppressed the expression of myogenin and myosin heavy chain in a concentration-dependent manner. Consistent with this, expression of a wild-type p38 MAPK (Ha-p38) or a constitutively active MAPK kinase 6 (MKK6(glu)) promoted the rate of differentiation into multinucleated myotubes. LY294002, a PI3-kinase inhibitor, suppressed in a dose-dependent manner not only muscle differentiation but also activation of p38 MAPK. In addition, expression of a constitutively active form of PI3-kinase (p110*) enhanced myotube formation and p38 MAPK activation, while expression of a dominant negative form of PI3-kinase (Deltap85) attenuated these responses. Furthermore, SB203580 suppressed differentiation of H9c2 cells expressing p110*. Interestingly, LY294002 also suppressed differentiation of H9c2 cells expressing Ha-p38 or MKK6(glu). However, SB203580 did not affect PI3-kinase activity, suggesting that PI3-kinase myogenic signaling to p38 MAPK is unidirectional. Taken together, we concluded that PI3-kinase activates p38 MAPK, which in turn stimulates muscle differentiation, but that p38 MAPK does not substitute for PI3-kinase in this process.

Expression of stable hepatitis B viral polymerase associated with GRP94 in E. coli

We here presented evidence that a 94-kDa glucose-regulated protein (GRP94) was associated with hepatitis B viral (HBV) polymerase in the human liver cell HepG2 and this association could be applied even in Escherichia coli. We investigated the role of GRP94 in the expression and stabilization of HBV polymerase in Escherichia coli by coexpression of the two proteins. The affinity column-purified glutathione S-transferase-tagged HBV polymerase (GST-P, 130 kDa) showed a proper molecular size and reverse transcriptase activity on several exogenous templates and was sensitive to specific inhibitors. The GST-P was associated with the maltose-binding protein-tagged GRP94 (MBP-GRP94, 130 kDa) using analyses by an affinity chromatography, native gel electrophoresis and glycerol gradient centrifugation. However, nondenaturing and partially denaturing activity gel analyses showed two active bands of approximately 260 kDa and approximately 130 kDa, respectively. Furthermore, in the presence of the encapsidation signal RNA template (HBV epsilon RNA), the approximately 260-kDa active band was gradually converted to approximately 130 kDa, which implies that HBV polymerase was dissociated from the chaperone GRP94 and bound preferentially to the HBV epsilon RNA. These results suggested that the chaperone GRP94 was necessary for the stabilization and production of HBV polymerase as an active form.

Recombinant bactericidal/permeability-increasing protein (rBPI21) as adjunctive treatment for children with severe meningococcal sepsis: a randomised trial. rBPI21 Meningococcal Sepsis Study Group

BACKGROUND

Endotoxin is a primary trigger of the inflammatory processes that lead to shock, multiorgan failure, and purpura fulminans in meningococcal sepsis. Bactericidal/permeability-increasing protein (BPI) is a natural protein, stored within the neutrophil granules, that binds to and neutralises the effects of endotoxin in vitro, in laboratory animals, and in humans. To establish whether a recombinant 21-kDa modified fragment of human BPI (rBPI21), containing the active antimicrobial and endotoxin-neutralising moiety, would decrease death and long-term disability from meningococcal sepsis, we did a randomised, double-blind, placebo-controlled trial of rBPI21 in children with severe meningococcal sepsis.

METHODS

We enrolled children (2 weeks to 18 years of age) presenting to 22 centres in the UK and the USA with a clinical picture suggestive of meningococcal sepsis, and with evidence of severe disease. Children were randomly assigned rBPI21 (2 mg/kg over 30 min followed by 2 mg/kg over 24 h) or placebo (0.2 mg/mL human albumin solution) in addition to conventional medical therapy. Primary outcome variables were mortality, amputations, and change in paediatric overall performance category (POPC) from before illness to day 60. Analysis was by intention to treat.

FINDINGS

Of 1287 patients screened, 892 were excluded, including 57 patients who died or who met criteria for imminent death before receiving the study drug. 190 patients received rBPI21, and 203 placebo. 34 (8.7%) of 393 patients died during the study: 14 (7.4%) in the rBPI21 group and 20 (9.9%) in the placebo group (odds ratio 1.31 [95% CI 0.62-2.74], p=0.48). Compared with patients randomised to placebo, fewer patients treated with rBPI21 had multiple severe amputations (six of 190 [3.2%] vs 15 of 203 [7.4%], odds ratio 2.47 [0.94-6.51], p=0.067), and more had a functional outcome similar to that before illness (as measured by the POPC scale) at day 60 (136 of 176 [77.3%] vs 126 of 190 [66.3%], p=0.019).

INTERPRETATION

Because most deaths occurred in the interval between identification of patients and study drug administration, the mortality rate in the placebo group was substantially lower than predicted. The trial was therefore underpowered to detect significant differences in mortality. However, patients receiving rBPI21 had a trend towards improved outcome in all primary outcome variables. Given the excellent severity match between placebo and rBPI21 groups at study entry, the results overall indicate that rBPI21 is beneficial in decreasing complications of meningococcal disease.

Evidence that the reactivity of the martian soil is due to superoxide ions

The Viking Landers were unable to detect evidence of life on Mars but, instead, found a chemically reactive soil capable of decomposing organic molecules. This reactivity was attributed to the presence of one or more as-yet-unidentified inorganic superoxides or peroxides in the martian soil. Using electron paramagnetic resonance spectroscopy, we show that superoxide radical ions (O2-) form directly on Mars-analog mineral surfaces exposed to ultraviolet radiation under a simulated martian atmosphere. These oxygen radicals can explain the reactive nature of the soil and the apparent absence of organic material at the martian surface.

Methylation of the ribosyl moiety at position 34 of selenocysteine tRNA[Ser]Sec is governed by both primary and tertiary structure

The selenocysteine (Sec) tRNA[Ser]Sec population in higher vertebrates consists of two major isoacceptors that differ from each other by a single nucleoside modification in the wobble position of the anticodon (position 34). One isoacceptor contains 5-methylcarboxymethyluridine (mcmU) in this position, whereas the other contains 5-methylcarboxymethyluridine-2'-O-methylribose (mcmUm). The other modifications in these tRNAs are N6-isopentenyladenosine (i6A), pseudouridine (psi), and 1-methyladenosine (m1A) at positions 37, 55, and 58, respectively. As methylation of the ribose at position 34 is influenced by the intracellular selenium status and the presence of this methyl group dramatically alters tertiary structure, we investigated the effect of the modifications at other positions as well as tertiary structure on its formation. Mutations were introduced within a synthetic gene encoded in an expression vector, transcripts generated and microinjected into Xenopus oocytes, and the resulting tRNA products analyzed for the presence of modified bases. The results suggest that efficient methylation of mcmU to yield mcmUm requires the prior formation of each modified base and an intact tertiary structure, whereas formation of modified bases at other positions, including mcmU, is not as stringently connected to precise primary and tertiary structure. These results, along with the observations that methylation of mcmU is enhanced in the presence of selenium and that this methyl group affects tertiary structure, further suggest that the mcmUm isoacceptor must have a role in selenoprotein synthesis different from that of the mcmU isoacceptor.

Enhanced detection of left atrial spontaneous echo contrast by transthoracic harmonic imaging in mitral stenosis

BACKGROUND

Spontaneous echo contrast (SEC) of the left atrium is associated with increased risk of thromboembolism in patients with mitral stenosis (MS). The determination of the presence and severity of left atrial (LA) SEC is of prognostic importance in these patients. Harmonic imaging (HI), a novel echocardiographic technique that differs from conventional fundamental imaging (FI) in that it involves transmitting ultrasound at one frequency and receiving at twice the transmitted frequency, produces better endocardial border definition and myocardial opacification. However, there are no data about its value for the detection of LA SEC. The purpose of this study was to investigate the utility of transthoracic noncontrast tissue HI in the detection of LA SEC in patients with MS.

METHODS

Seventy-four consecutive patients with MS (49 women, mean age 51 years) underwent standard transthoracic echocardiography (TTE) in both HI and FI modes and transesophageal echocardiography (TEE) to determine the presence and severity of LA SEC. Left atrial SEC was graded by TEE as either mild (only seen at high gain) or severe (visible in the entire left atrium at normal gain control of the equipment). The control group comprised 30 patients randomly selected from patients who did not have LA SEC at the TEE examination.

RESULTS

Atrial fibrillation was found in 46 patients (62.2%). The mean mitral valve area and mean mitral gradient were 1.0+/-0.3 cm(2) and 8.2+/-4.1 mm Hg, respectively. Nine patients (12.2%) had episodes of systemic embolism; 8 had stroke, and 1 had peripheral embolism. Left atrial thrombus was found in 11 patients (14.9%) by TEE. Left atrial SEC was present in all but one patient by TEE (mild in 35 patients, severe in 38). Fundamental imaging with TTE, however, revealed LA SEC in only 5 (6.8%) of the 73 patients. In contrast, with HI, LA SEC could be detected in 63 (86.3%) patients. In the detection of severe LA SEC, the sensitivities of FI and HI were 13.2% (5/38) and 100% (38/38), respectively. Left atrial SEC was not observed in control subjects by either FI or HI.

CONCLUSIONS

Transthoracic HI significantly enhances the detection of LA SEC in patients with MS.

Optical properties of a thin-film stack illuminated by a focused field

Reflectance (R), transmittance (T), and absorptance (A) are calculated for a thin-film stack illuminated by a focused field. Based on Debye's integral representation, the electric and magnetic fields near focus are obtained, and the formulas for R, T, and A are represented as integrals of Poynting vectors. This formulation is applied to the case of a numerical aperture (N.A.) greater than 1.0 as well as to the case of a N.A. less than 1.0, and the corresponding numerical results are presented. They reveal that R, T, and A vary with N.A. and that the amount of variation increases with layer thickness.

Response of urinary lipophilic aldehydes and related carbonyl compounds to factors that stimulate lipid peroxidation in vivo

Peroxidation of lipids results in the formation of a number of aldehydic and other carbonyl-containing secondary degradation products. The effect of peroxidative stimuli mediated by vitamin E deficiency, a diet high in polyunsaturated fatty acids (containing cod liver oil), and carbon tetrachloride administration on urinary excretion of a number of lipophilic aldehydes and related carbonyl compounds was examined in rats. These secondary lipid peroxidation products were measured as 2,4-dinitrophenylhydrazine derivatives. All three treatments increased urinary excretion of secondary lipid peroxidation products, although the pattern of excretion of these products varied somewhat among the treatments. Significant increases were found in butanal, hexanal, octanal, butan-2-one, pentan-2-one, hex-2-enal, hepta-2,4-dienal, 4-hydroxyhex-2-enal, 4-hydroxyoct-2-enal, 4-hydroxynon-2-enal, and a number of unidentified carbonyl compounds. These results suggest that urinary excretion of these lipophilic secondary lipid peroxidation products is a useful and noninvasive marker of whole-body lipid peroxidation.

Indirect signs of anterior cruciate ligament injury on SPET: comparison with MRI and arthroscopy

Indirect signs of anterior cruciate ligament (ACL) injury on magnetic resonance imaging (MRI) include bony contusions in the lateral femoral condyle and the posterior portion of the lateral tibial plateau. This study was undertaken to assess the value of single photon emission tomography (SPET) in the diagnosis of ACL injury by examining the uptake pattern in the distal femur and the proximal tibia. Thirty-five patients were examined using SPET, MRI and arthroscopy. Seventeen patients were found to have ACL tears on arthroscopy. The duration of symptoms was 4 days to 10 years (mean 26.4 months). MRI and SPET images were analysed retrospectively without information from arthroscopic examination. Radionuclide uptake in the lateral femoral condyle and the posterior lateral tibial plateau was considered an indirect sign of ACL injury on SPET. We evaluated the diagnostic value of indirect signs of ACL injury obtained on SPET by comparing these findings with arthroscopic and MRI results. Fifteen of 17 patients with ACL injury showed indirect signs on SPET. The sensitivity, specificity, positive predictive value and negative predictive value for indirect signs of ACL injury were 88%, 56%, 65% and 83% on SPET and 59%, 94%, 91% and 71% on MRI, respectively. However, despite the higher sensitivity of indirect signs on SPET than on MRI, the overall diagnostic value of MRI is better than that of SPET. In the clinical setting, indirect signs of ACL injury may be of value in interpreting incidental findings on SPET.

Progression of hepatic stellate cell activation is associated with the level of oxidative stress rather than cytokines during CCl4-induced fibrogenesis

In order to identify a fibrogenic factor associated with the potential of hepatic stellate cells (HSC) activation that arises during the CCl4-induced fibrogenic process, the relationship between the activation of HSC and levels of several fibrogenic factors were investigated. After isolation of HSC from the liver at different stages of CCl4 intoxication, the activation of HSC was assessed by the expression of alpha-smooth muscle actin. Levels of cytokines and oxidative stress in liver homogenates and plasma were measured by enzyme linked immunosorbent assay and the colorimetric method. In primary culture, HSC isolated from a rat liver were gradually activated in a time-dependent manner according to CCl4 administration. The progression of HSC activation was closely correlated with parameters related to oxidative stress in liver homogenates rather than the tissue levels of several cytokines. Also, the levels of antioxidants and arginase activity were inversely correlated with HSC activation. In plasma, the levels of oxidative stress and cytokines in CCl4-treated rat livers were not associated with the activation of HSC found during the CCl4-induced fibrogenic process. The relationship between HSC activation and oxidative stress was also confirmed through several factor-treated HSC cultures. In conclusion, the activation of HSC was accelerated according to CCl4 administration, and the progression of HSC activation is absolutely related to the oxidative stress. These results show that enhanced oxidative stress is an important signal for activation of HSC in experimental liver fibrogenesis.