A Mixture of Morus alba and Angelica keiskei Leaf Extracts Improves Muscle Atrophy by Activating the PI3K/Akt/mTOR Signaling Pathway and Inhibiting FoxO3a In Vitro and In Vivo

Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus, modulating the homeostasis between muscle protein synthesis and degradation represents an efficient treatment approach for this condition. In the present study, the protective effects against muscle atrophy of ethanol extracts of Morus alba L. (MA) and Angelica keiskei Koidz. (AK) leaves and their mixtures (MIX) were evaluated in vitro and in vivo. Our results showed that MIX increased 5-aminoimidazole-4-carboxamide ribonucleotide-induced C2C12 myotube thinning, and enhanced soleus and gastrocnemius muscle thickness compared to each extract alone in dexamethasone-induced muscle atrophy Sprague Dawley rats. In addition, although MA and AK substantially improved grip strength and histological changes for dexamethasone-induced muscle atrophy in vivo, the efficacy was superior in the MIX-treated group. Moreover, MIX further increased the expression levels of myogenic factors (MyoD and myogenin) and decreased the expression levels of E3 ubiquitin ligases (atrogin-1 and muscle-specific RING finger protein-1) in vitro and in vivo compared to the MA- and AK-alone treatment groups. Furthermore, MIX increased the levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) that were reduced by dexamethasone, and downregulated the expression of forkhead box O3 (FoxO3a) induced by dexamethasone. These results suggest that MIX has a protective effect against muscle atrophy by enhancing muscle protein anabolism through the activation of the PI3K/Akt/mTOR signaling pathway and attenuating catabolism through the inhibition of FoxO3a.

Mixture of Corni Fructus and Schisandrae Fructus improves testosterone-induced benign prostatic hyperplasia through regulating 5α-reductase 2 and androgen receptor

BACKGROUND/OBJECTIVES

Benign prostatic hyperplasia (BPH) characterized by an enlarged prostate gland is common in elderly men. Corni Fructus (CF) and Schisandrae Fructus (SF) are known to have various pharmacological effects, including antioxidant and anti-inflammatory activities. In this study, we evaluated the inhibitory efficacy of CF, SF, and their mixture (MIX) on the development of BPH using an in vivo model of testosterone-induced BPH.

MATERIALS/METHODS

Six-week-old male Sprague-Dawley rats were randomly divided into seven groups. To induce BPH, testosterone propionate (TP) was injected to rats except for those in the control group. Finasteride, saw palmetto (SP), CF, SF, and MIX were orally administered along with TP injection. At the end of treatment, histological changes in the prostate and the level of various biomarkers related to BPH were evaluated.

RESULTS

Our results showed that BPH induced by TP led to prostate weight and histological changes. Treatment with MIX effectively improved TP-induced BPH by reducing prostate index, lumen area, epithelial thickness, and expression of BPH biomarkers such as 5α-reductase type 2, prostate-specific antigen, androgen receptor, and proliferating cell nuclear antigen compared to treatment with CF or SF alone. Moreover, MIX further reduced levels of elevated serum testosterone, dihydrotestosterone, and prostate-specific antigen in BPH compared to the SP, a positive control. BPH was also improved more by MIX than by CF or SF alone.

CONCLUSIONS

Based on the results, MIX is a potential natural therapeutic candidate for BPH by regulating 5α-reductase and AR signaling pathway.

Protective Effect of Gamma Aminobutyric Acid against Aggravation of Renal Injury Caused by High Salt Intake in Cisplatin-Induced Nephrotoxicity

Gamma-aminobutyric acid (GABA) is one of the inhibitory neurotransmitters. Several studies have suggested that GABA supplements can reduce blood pressure and modulate the renal immune system in vitro and in vivo. In the present study, we investigated the effect of GABA-enriched salt as an alternative to traditional salt on aggravated renal injury by high salt intake in cisplatin-induced nephrotoxicity mice. High salt intake accelerated the increase of biomarkers, such as blood urea nitrogen and serum creatinine levels for renal injury in cisplatin-induced nephrotoxicity mice. However, oral administration of GABA-contained salt notably suppressed serum BUN and creatinine levels. The efficacy of GABA salt was superior to lacto GABA salt and postbiotics GABA salt. Furthermore, GABA-enriched salt markedly restored histological symptoms of nephrotoxicity including renal hypertrophy, tubular dilation, hemorrhage, and collagen deposition aggravated by salt over-loading in cisplatin-exposed mice. Among them, GABA salt showed a higher protective effect against cisplatin-induced renal histological changes than lacto GABA salt and postbiotics GABA salt. In addition, administration of high salt significantly enhanced expression levels of apoptosis and inflammatory mediators in cisplatin-induced nephrotoxicity mice, while GABA-enriched salt greatly down-regulated the expression of these mediators. Taken together, these results demonstrate the protective effect of GABA against damage caused by high salt intake in cisplatin-induced renal toxicity. Its mechanism may be due to the suppression of hematological and biochemical toxicity, apoptosis, and inflammation. In conclusion, although the protective efficacy of GABA salt on renal injury is different depending on the sterilization and filtration process after fermentation with L. brevis BJ20 and L. plantarum BJ21, our findings suggest that GABA-enriched salt has a beneficial effect against immoderate high salt intake-mediated kidney injury in patients with cisplatin-induced nephrotoxicity.

ROS1 Kinase Inhibitors for Molecular-Targeted Therapies

ROS1 is a pivotal transmembrane receptor protein tyrosine kinase which regulates several cellular processes like apoptosis, survival, differentiation, proliferation, cell migration, and transformation. There is increasing evidence supporting that ROS1 plays an important role in different malignancies including glioblastoma, colorectal cancer, gastric adenocarcinoma, inflammatory myofibroblastic tumor, ovarian cancer, angiosarcoma, and non small cell lung cancer; thus, ROS1 has become a potential drug discovery target. ROS1 shares about 49% sequence homology with ALK primary structure; therefore, wide range of ALK kinase inhibitors have shown in vitro inhibitory activity against ROS1 kinase. After Crizotinib approval by FDA for the management of ALK-rearranged lung cancer, ROS1-positive tumors have been focused. Although significant advancements have been achieved in understanding ROS1 function and its signaling pathways plus recent discovery of small molecules modulating ROS1 protein, a vital need of medicinal chemistry efforts is still required to produce selective and potent ROS1 inhibitors as an important therapeutic strategy for different human malignancies. This review focuses on the current knowledge about different scaffolds targeting ROS1 rearrangements, methods to synthesis, and some biological data about the most potent compounds that have delivered various scaffold structures.

Topographic measurement of skin color by narrow-band reflectance spectrophotometer and minimal erythema dose (MED) in Koreans

BACKGROUND/AIMS

Narrow-band reflectance spectrophotometer is one of the objective and quantitative devices for measuring the skin colors. There has been some controversy concerning the relationship between the objectively measured skin color and cutaneous responsiveness to ultraviolet radiation, including minimal erythema dose (MED). The aims of this study were to compare the color of Korean brown skin with that of Caucasians by objective measurement with the narrow-band reflectance spectrophotometer, and to determine whether the skin color has any correlation with MED in Koreans, and demonstrate differences in this correlation according to the anatomical sites.

METHODS

With narrow-band reflectance spectrometer, skin colors were measured at 17 body sites of 20 healthy Korean male volunteers after measuring MED for the same subjects.

RESULTS

The constitutional skin color, as measured by the melanin index of the nonexposed sites, showed a statistically significant correlation with MED values, whereas the facultative skin color did not. The Korean brown skin showed higher melanin index and lower erythema index compared with that of Caucasians.

CONCLUSIONS

We confirmed significant differences in the correlation between MED and melanin indices, depending on the anatomic sites. This suggests that selection from various sites, even among the nonexposed sites, is quite important and deserves further evaluation.

Anti-Müllerian hormone promotes pre-antral follicle growth, but inhibits antral follicle maturation and dominant follicle selection in primates

STUDY QUESTION

What are the direct effects and physiological role of anti-Müllerian hormone (AMH) during primate follicular development and function at specific stages of folliculogenesis?

SUMMARY ANSWER

AMH actions in the primate ovary may be stage-dependent, directly promoting pre-antral follicle growth while inhibiting antral follicle maturation and dominant follicle selection.

WHAT IS KNOWN ALREADY

AMH is expressed in the adult ovary, particularly in developing follicles. Studies in mice suggest that AMH suppresses pre-antral follicle growth in vitro, and inhibits primordial follicle recruitment and FSH-stimulated antral follicle steroidogenesis.

STUDY DESIGN, SIZE, DURATION

For in vitro study, secondary follicles were isolated from ovaries of 12 rhesus macaques and cultured for 5 weeks. For in vivo study, intraovarian infusion was conducted on five monkeys for the entire follicular phase during two spontaneous menstrual cycles.

PARTICIPANTS/MATERIALS, SETTING, METHODS

For in vitro study, individual follicles were cultured in a 5% O2 environment, in alpha minimum essential medium supplemented with recombinant human FSH. Follicles were randomly assigned to treatments of recombinant human AMH protein or neutralizing anti-human AMH antibody (AMH-Ab). Follicle survival, growth, steroid production, steroidogenic enzyme expression, and oocyte maturation were assessed. For in vivo study, ovaries were infused with control vehicle or AMH-Ab during the follicular phase of the menstrual cycle. Cycle length, serum steroid levels, and antral follicle growth were evaluated.

MAIN RESULTS AND THE ROLE OF CHANCE

AMH exposure during culture weeks 0-3 (pre-antral stage) promoted, while AMH-Ab delayed, antrum formation of growing follicles compared with controls. AMH treatment during culture weeks 3-5 (antral stage) decreased (P < 0.05) estradiol (E2) production, as well as the mRNA expression of cytochrome P450 family 19 subfamily A polypeptide 1, by antral follicles relative to controls, whereas AMH-Ab increased (P < 0.05) follicular mRNA levels of the enzyme. Intraovarian infusion of AMH-Ab during the follicular phase of the menstrual cycle increased (P < 0.05) the average levels of serum E2 compared with those of the control cycles. Three of the five AMH-Ab-treated ovaries displayed multiple (n = 2-9) medium-to-large (2-8 mm) antral follicles at the mid-cycle E2 peak, whereas only one large (4-7 mm) antral follicle was observed in all monkeys during their control cycles. The average levels of serum progesterone were higher (P < 0.05) during the luteal phase of cycles following the AMH-Ab infusion relative to the vehicle infusion.

LIMITATIONS, REASONS FOR CAUTION

The in vitro study of AMH actions on cultured individual macaque follicles was limited to the interval from the secondary to small antral stage. A sequential study design was used for in vivo experiments, which may limit the power of the study.

WIDER IMPLICATIONS OF THE FINDINGS

The current study provides novel information on direct actions and role of AMH during primate follicular development, and selection of a dominant follicle by the late follicular phase of the menstrual cycle. We hypothesize that AMH acts positively on follicular growth during the pre-antral stage in primates, but negatively impacts antral follicle maturation, which is different from what is reported in the mouse model.

STUDY FUNDING/COMPETING INTERESTS

NIH NICHD R01HD082208, NIH ORWH/NICHD K12HD043488 (BIRCWH), NIH OD P51OD011092 (ONPRC), Collins Medical Trust. There are no conflicts of interest.

TRIAL REGISTRATION NUMBER

Not applicable.

Increase of transcription factor EB (TFEB) and lysosomes in rat DRG neurons and their transportation to the central nerve terminal in dorsal horn after nerve injury

In the spinal dorsal horn (DH), nerve injury activates microglia and induces neuropathic pain. Several studies clarified an involvement of adenosine triphosphate (ATP) in the microglial activation. However, the origin of ATP together with the release mechanism is unclear. Recent in vitro study revealed that an ATP marker, quinacrine, in lysosomes was released from neurite terminal of dorsal root ganglion (DRG) neurons to extracellular space via lysosomal exocytosis. Here, we demonstrate a possibility that the lysosomal ingredient including ATP released from DRG neurons by lysosomal-exocytosis is an additional source of the glial activation in DH after nerve injury. After rat L5 spinal nerve ligation (SNL), mRNA for transcription factor EB (TFEB), a transcription factor controlling lysosomal activation and exocytosis, was induced in the DRG. Simultaneously both lysosomal protein, LAMP1- and vesicular nuclear transporter (VNUT)-positive vesicles were increased in L5 DRG neurons and ipsilateral DH. The quinacrine staining in DH was increased and co-localized with LAMP1 immunoreactivity after nerve injury. In DH, LAMP1-positive vesicles were also co-localized with a peripheral nerve marker, Isolectin B4 (IB4) lectin. Injection of the adenovirus encoding mCherry-LAMP1 into DRG showed that mCherry-positive lysosomes are transported to the central nerve terminal in DH. These findings suggest that activation of lysosome synthesis including ATP packaging in DRG, the central transportation of the lysosome, and subsequent its exocytosis from the central nerve terminal of DRG neurons in response to nerve injury could be a partial mechanism for activation of microglia in DH. This lysosome-mediated microglia activation mechanism may provide another clue to control nociception and pain.

Staurosporine analogues from microbial and synthetic sources and their biological activities

In 1977 an unknown natural product was isolated from Streptomyces staurosporeus by Omura et al. during a search for new alkaloids present in actinomycetes and was given the name AM-2282. Later, the structure of AM-2282 was elucidated by single crystal X-ray analysis and renamed as staurosporine. It has been published that staurosporine and its analogues display strong inhibitory effect against a variety of kinases and a number of biological properties such as antifungal, antibacterial, and immunosuppressive activities. Despite strong inhibitory activity of staurosporine, a very high level of cross-reactivity makes it impossible to use staurosporine as a therapeutic agent. In the course of searching for other staurosporine-related compounds, a number of staurosporine analogues have been isolated from different microorganisms. In addition, a number of staurosporine analogues have been synthesized to improve the poor selectivity and target specificity of staurosporine which limited its clinical effectiveness. The review addresses staurosporine analogues from both microbial and synthetic sources and their biological activities.

Design and construction of a compact microwave proton source for a proton linac

A 100 MeV, 20 mA proton linear accelerator is being developed by the Proton Engineering Frontier Project at the Korea Atomic Energy Research Institute. 20 MeV acceleration system using radio frequency quadrupole and drift tube linac was already developed and has been tested. To operate this acceleration system with a long time, more reliable proton source is needed. A compact microwave proton source was proposed and has been designed and constructed as a prototype ion source for the 100 MeV proton linear accelerator. The design of microwave power injection system is based on the microwave proton injector at LANL and CEA. The wave power from a 2.45 GHz, 2 kW magnetron source is introduced into a compact plasma chamber with 7 cm diameter and 5 cm length through a standard tapered, double-ridged waveguide (WRD250) and a quartz window. The microwave power supply is installed on high voltage platform. Axial magnetic fields up to 1 kG can be provided with a water-cooled solenoid coil. A single-hole three electrode extraction system is designed for an extraction current up to 30 mA at a 50 kV extraction voltage. The design and initial operations of the proton source are presented.

Utilization of house fly-maggots, a feed supplement in the production of broiler chickens

Recent studies have suggested the utilization of maggots as a feed supplement forenhanced broiler performance. Maggots, which are a major dietary source of protein, appear during the biodegradation of chicken droppings using house flies. The objective ofthe present study was to investigate the effect of maggot supplementation on the meat quality and growth performance of broiler chickens. A total of 600 one-day-old male commercial broiler chicks (Ross) were randomly assigned into 5 treatment groups consisting of 40 replicates of 3 birds. The birds were fed either a basal diet or the basal diet supplemented with 5.0, 10.0, 15.0 and 20.0% maggots. Overall, broiler chicken performance was influenced by the optimal amino acid profile; high protein (63.99%) and essential amino acid content (29.46%), or high protein digestibility (98.50%) of the maggots. Maggot supplementation caused linear increases in live weight gain but not the feed conversion ratio. The diets of 10 and 15% maggots was the most efficient in terms of average weight gain forthe 4-5 week old broiler chickens (p<0.05). It also significantly increased dressing percentage, breast muscle, and thigh muscle (p<0.05). No differences were observed forliver abdominalfat, or meat color, and the crude protein contents of breast muscle were constant. However, in the maggot-fed broilers, breast muscle lysine and tryptophan levels increased significantly as compared to the birds fed the basal diet (p<0.05). These results indicate that feeding diets containing 10 to 15% maggots in chicken dropping after biodegradation can improve the carcass quality and growth performance of broiler chickens.

A case of disseminated Nocardia farcinica diagnosed through DNA sequencing in a kidney transplantation patient

Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.

Long term disease-free survival in acute leukemia patients recovering with increased γδ T cells after partially mismatched related donor bone marrow transplantation

Allogeneic stem cell transplantation (ASCT) has improved leukemia-free survival (LFS) in many but not all patients with acute leukemia. This is an eight-year follow-up to our previous study showing a survival advantage to patients with an increased gammadelta T cells following ASCT. gammadelta T cell levels were collected prospectively in 153 patients (acute lymphoblastic leukemia (ALL) n = 77; acute myelogenous leukemia (AML) n = 76) undergoing partially mismatched related donor ASCT. Median age was 22 years (1-59), and 62% of the patients were in relapse at transplant. Patient-donor human leukocyte antigen (HLA) disparity of three antigens was 37% in the graft-versus-host disease (GvHD) and 29% in the rejection directions. All patients received a partially T cell-depleted graft using T10B9 (n = 46) or OKT3 (n = 107). Five years LFS and overall survival (OS) of patients with increased gammadelta compared to those with normal/decreased numbers were 54.4 vs 19.1%; P < 0.0003, and 70.8 vs 19.6% P < 0.0001, respectively, with no difference in GvHD (P = 0.96). In a Cox multivariate analysis, normal/decreased gammadelta (hazard ratio (HR) 4.26, P = 0.0002) and sex mismatch (HR 1.45 P=0.049) were associated with inferior LFS. In conclusion, gammadelta T cells may facilitate a graft-versus-leukemia (GvL) effect, without causing GvHD. Further evaluations of this effect may lead to specific immunotherapy for patients with refractory leukemia.

Suppression of ochratoxin biosynthesis by naturally occurring alkaloids

The effects of four alkaloids on the biosynthesis of ochratoxin A (OTA), ochratoxin B (OTB) and citrinin were examined on four OTA-producing aspergilli: Aspergillus auricomus, A. sclerotiorum and two isolates of A. alliaceus. Piperine and piperlongumine, natural alkaloids of Piper longum, significantly inhibited OTA production at 0.001% (w/v) for all aspergilli examined. Piperine and piperlongumine affected the polyketide synthesis step of OTA production and inhibited production of citrinin. Curcumin, a constituent of tumeric, completely inhibited mycelial growth of A. alliaceus isolate 791 at 0.1% (w/v) and decreased OTA production by approximately 70% at 0.01% (w/v). Sesamin, a constituent of sesame oil, inhibited OTA and OTB production by 60 and 45%, respectively, at 0.1% (w/v), showing its effect was on chloroperoxidase and polyketide synthase activity. The potential advantage of these natural products to reduce ochratoxin contamination of agricultural commodities is discussed.

Risk assessment of human exposure to cypermethrin during treatment of mandarin fields

The potential dermal and respiratory exposure assessment and risk assessment for applicator were performed with cypermethrin EC. The pesticide was applied on a mandarin field using a power sprayer. Gloves were used for the hand exposure assessment, mask for face, and dermal patches for the other parts of the body. Personal air monitor equipped with a XAD-2 resin was used for the respiratory exposure assessment. During the application of cypermethrin in the field, the rate of potential dermal exposure ranged from 28.1 to 58.8 mg/h. The major exposure parts were upper-arms (22.1-24.6%) and legs (thigh and shin, 28.3-29.2%) for females and thigh (21.0-46.9%) and hand (14.9-19.3%) for males. Females were exposed more than males. No exposure was detected from the respiratory monitoring. For risk assessment, the potential dermal exposure (PDE), the absorbable quantity of exposure (AQE), and the margin of safety (MOS) were calculated. Among those four risk assessments, MOS was < 1 in only trial I, which indicated any possibility of risk. However, in the others, the possibility of risk was little. Moreover, the safe work time ranged from 3.61 h to 9.69 h.

Characterization of a pollen-preferential gene, BAN102, from Chinese cabbage

We isolated and characterized a pollen-preferential gene, BAN102, from Chinese cabbage and analyzed the activity of its promoter. There were three or four copies of the BAN102 gene in the Chinese cabbage genome that specifically expressed in pollen and pollen tube. There were 2137 bp of BAN102 genomic clone comprising 186 bp of protein coding region, and 1178 bp of 5' and 773 bp of 3' non-coding regions. TATA box were located at 1071 nt of the promoter region while the polyadenylation signal and polyadenylation site were at 1470 and 1486 nt of the 3' non-coding region. BLAST search of BAN102 sequence showed that coding region of BAN102 gene was the greatest percent similarity with arabinogalactan protein (AGP23) gene from Arabidopsis thaliana. Promoter analysis using GUS gene as a reporter showed that the pollen-specificity of BAN102 resided within the -112 to -44 bp of proximal promoter from the transient expression in tobacco and Chinese cabbage plants.

Physical mapping and microsynteny of Brassica rapa ssp. pekinensis genome corresponding to a 222 kbp gene-rich region of Arabidopsis chromosome 4 and partially duplicated on chromosome 5

We constructed a bacterial artificial chromosome (BAC) library, designated as KBrH, from high molecular weight genomic DNA of Brassica rapa ssp. pekinensis (Chinese cabbage). This library, which was constructed using HindIII-cleaved genomic DNA, consists of 56,592 clones with average insert size of 115 kbp. Using a partially duplicated DNA sequence of Arabidopsis, represented by 19 and 9 predicted genes on chromosome 4 and 5, respectively, and BAC clones from the KBrH library, we studied conservation and microsynteny corresponding to the Arabidopsis regions in B. rapa ssp. pekinensis. The BAC contigs assembled according to the Arabidopsis homoeologues revealed triplication and rearrangements in the Chinese cabbage. In general, collinearity of genes in the paralogous segments was maintained, but gene contents were highly variable with interstitial losses. We also used representative BAC clones, from the assembled contigs, as probes and hybridized them on mitotic (metaphase) and/or meiotic (leptotene/pachytene/metaphase I) chromosomes of Chinese cabbage using bicolor fluorescence in situ hybridization. The hybridization pattern physically identified the paralogous segments of the Arabidopsis homoeologues on B. rapa ssp. pekinensis chromosomes. The homoeologous segments corresponding to chromosome 4 of Arabidopsis were located on chromosomes 2, 8 and 7, whereas those of chromosome 5 were present on chromosomes 6, 1 and 4 of B. rapa ssp. pekinensis.

Mechanism of histone deacetylase inhibitor Trichostatin A induced apoptosis in human osteosarcoma cells

Although histone deacetylase (HDAC) inhibitors are emerging as a promising new treatment strategy in malignancy, how they exert their effect on osteosarcoama cells is as yet unclear. This study was undertaken to investigate the underlying mechanism of a HDAC inhibitor Trichostatin A (TSA)-induced apoptosis in a osteosarcoma cell line HOS. We observed that TSA treatment decreased the viability of the cells and prominently increased acetylation of histone H3. Evidence was obtained indicating that TSA induced apoptosis of HOS cells as follows: (1) Generation of DNA fragmentation; (2) activation of procaspase-3; (3) cleavage of PARP; and (4) increase of DNA hypoploidy. The reduction of MMP and the release of cytochrome c to cytosol were also shown, indicating that TSA induces apoptosis in HOS cells in a histone acetylation- and mitochondria-dependent fashions. We also examined whether TSA can sensitize HOS cells to the action of an antitumor agent genistein. The combination therapy of TSA and genistein showed synergistic anticancer effect indicating that TSA can be considered as a novel therapeutic strategy for osteosarcoma not only from its direct apoptosis-inducing activity but also from the possibility of sensitization to other antitumor agents.

Phospho-ser 15-p53 translocates into mitochondria and interacts with Bcl-2 and Bcl-xL in eugenol-induced apoptosis

Our previous studies demonstrated that antiallergic effects of herbs such as clove and Magnoliae Flos (MF) resulted from the induction of apoptosis in mast cells. We here examined whether the antiallergic activity was caused by eugenol (4-allyl-2-methoxyphenol) which was one of major ingredients in the essential oils or extracts of numerous plants including clove and Magnoliae Flos. RBL-2H3 cells were treated with eugenol, and DNA electrophoresis, Western blotting, immunocytochemistry, confocal microscopy and immunoprecipitation were conducted. Effect of eugenol was tested using a rat anaphylaxis model. RBL-2H3 cells treated with eugenol showed typical apoptotic manifestations and translocation of p53 into mitochondria. Antisense p53 partially prevented the induction of apoptosis. Noticeably, we observed that p53 translocated into mitochondria was phosphorylated on ser 15. Phospho-ser 15-p53 physically interacted with Bcl-2 and Bcl-xL in mitochondria and its translocation into mitochondria preceded cytochrome c release and mitochondrial membrane potential (MMP) reduction. We also depicted that the survival of animals even after administration of the fatal dose of compound 48/80 might result from the decreased number of mast cells by eugenol pretreatment. In conclusion, eugenol induces apoptosis in mast cells via translocation of phospho-ser 15-p53 into mitochondria.

Szygium aromaticum (L.) Merr. Et Perry (Myrtaceae) flower bud induces apoptosis of p815 mastocytoma cell line

This study was conducted to investigate SAFB-induced apoptosis of mast cells as it pertains to both its basic drug mechanism and the potential therapeutics of the pathologic conditions accompanying mast cell proliferation. SAFB induced many apoptotic manifestations as evidenced by changes in cell morphology, generation of DNA fragmentation, activation of caspase 3, and DNA hypoploidy. The reduction of mitochondrial membrane potential and the release of cytochrome c to cytosol were also demonstrated. However, reduction of mitochondrial membrane potential and cytochrome c release were not prevented by caspase inhibitor zVAD-fmk or PTP blockers such as bongkrekic acid and cyclosporin A. Expression levels of Bcl-2 and Fas remained unchanged following SAFB treatment. This results suggest that the clinical effect of SAFB may depend on the pharmacological mechanism regulating the demise of mast cells.

Fumigant toxicity of volatile natural products from Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae (L)

The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L. var piperascens (LC50 = 45.5 microliters litre-1 air). GC-MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by beta-pinene (0.7%), alpha-pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 microliters litre-1 air) followed by linalool (LC50 = 39.2 microliters litre-1 air) and alpha-pinene (LC50 = 54.9 microliters litre-1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine-fold lower inhibitory effect than menthol, despite menthone being 8.1-fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed.

The predictive parameters of erythropoietin hyporesponsiveness in patients on continuous ambulatory peritoneal dialysis

BACKGROUND

The present study was aimed at investigating the predictive parameters of erythropoietin (epoetin) hyporesponsiveness in patients on continuous ambulatory peritoneal dialysis (CAPD).

METHODS

We studied 40 patients with end-stage renal disease who had been receiving CAPD for at least 6 months and epoetin therapy for at least more than 2 months. Pearson's simple correlation and multiple stepwise linear regression analysis was used to discover what parameter can predict epoetin resistance. We expressed epoetin resistance index (ERI) as weekly epoetin dose/hematocrit/body weight'. The dose of epoetin is titrated by about 25% every 2 to 4 weeks to maintain a target hematocrit level between 33% and 36%.

RESULTS

We analyzed the relationship between ERI and other predictive parameters by Pearson's correlation. These results showed ERI has a statistically significant correlation with transferrin saturation (TS) (r = -0.327, p = 0.042), total weekly Kt/Vurea (r = -0.423, p = 0.018), serum albumin level (r = -0.458, p = 0.003), normalized protein catabolic rate (nPCR) (r = -0.479, p = 0.006), normalized protein equivalent of total nitrogen appearance (nPNA) (r = -0.488, p = 0.005) and serum C-reactive protein (CRP) (r = 0.332, p = 0.036). Regression analysis was performed using stepwise linear regression for multiple variables to discover the most independent variable which is correlated with ERI. ERI was entered as a dependent variable, whereas the other parameters (age, duration of peritoneal dialysis, serum albumin level, CRP, serum ferritin, total weekly Kt/Vurea, nPCR, nPNA, serum iPTH, serum aluminium, TS) were entered as independent variables. This analysis showed CRP is the most significant variable and, if CRP is excluded, nPNA is the significant variable. CRP has a statistically significant correlation with serum albumin level (r = -0.418, p = 0.007) and total weekly Kt/Vurea (r = -0.366, p = 0.043). High CRP group has more increased level of ERI (p < 0.05), age (p < 0.05) and serum creatinine level (p < 0.05) than normal control, but more decreased level of serum albumin (p < 0.01) and serum iron levels (p < 0.05).

CONCLUSION

These results indicate that CRP is the most important predictor of epoetin hyporesponsiveness.

Concurrence of replicative senescence and elevated expression of p16(INK4A) with subculture-induced but not calcium-induced differentiation in normal human oral keratinocytes

Primary normal human oral keratinocytes (NHOKs) undergo differentiation in the presence of calcium concentrations higher than 0.15 mM in vitro, which is useful in investigating the mechanisms involved in the differentiation of epithelial cells. Serial subculture of NHOKs to the postmitotic stage also induces terminal differentiation. However, the detailed mechanisms of both differentiation processes remain substantially unknown. To investigate the molecular differences in these processes, NHOKs were induced to differentiate by exposure to 1.2 mM of calcium and by serial subculture to the postmitotic stage. To study whether the cells were induced to differentiate and to undergo replicative senescence, the amount of cellular involucrin and the expression of senescence-associated beta-galactosidase (SA-beta-gal) were measured respectively. The expression of replicative senescence-associated genes and the activity of telomerase from the differentiated cells were also determined. Both calcium treatment and serial subculture to the postmitotic stage notably elevated the cellular involucrin. The percentage of SA-beta-gal-positive cells was significantly elevated by the continued subculture, but such changes were not observed in keratinocytes exposed to calcium. The concentration of cellular p16(INK4A) protein was progressively increased by the continued subculture but was not changed by calcium treatment. On the other hand, the concentrations of cellular p53 were similar in both differentiation processes. However, telomerase activity was lost in NHOKs that had undergone differentiation by both calcium treatment and serial subculture. The results indicate that calcium-induced differentiation of NHOKs has similar characteristics to their serial subculture-induced differentiation, but that the differentiation processes are not identical, because calcium-induced differentiation does not concur with either replicative senescence or the gradually increased concentration of p16(INK4A).

Genistein induces apoptosis of RPE-J cells by opening mitochondrial PTP

Although previous studies demonstrated that genistein-induced apoptosis of various cell types including RPE-J cells, the involvement of mitochondrial events in such types of apoptosis has not been demonstrated to date. In this investigation of genistein-induced apoptosis of RPE-J cells, genistein induced the reduction of the mitochondrial membrane potential and the release of cytochrome c to cytosol. A mitochondrial permeability transition pore (PTP) blocker bongkrekic acid prevented the reduction of the mitochondrial membrane potential and cytochrome c release, and consequently abolished caspase-3 activation, nuclear condensation, and DNA fragmentation. On the other hand, zVAD-fmk did not inhibit the mitochondrial event such as the reduction of the mitochondrial membrane potential and cytochrome c release although it prevented caspase-3 activation, nuclear condensation, and DNA fragmentation. Taken together, genistein induces apoptosis of RPE-J cells by opening the mitochondrial PTP, and the mitochondrial event in this type of apoptosis is caused independently of caspase.

Comparative quantitative analysis of ultraviolet B-induced skin blood flow change using laser Doppler perfusion imaging technique

Laser Doppler perfusion imaging (LDI), recently developed, can generate a color-coded image of tissue perfusion, making it possible to assess the spatial distribution of skin perfusion without touching the surface. Using this apparatus, we investigated ultraviolet B (UVB)-induced perfusion profile of the skin and compared the results with those obtained from laser Doppler flowmetry (LDF). Fifteen adult male Korean volunteers were irradiated with several doses of UVB ranging from 25 mJ/cm2 to 186 mJ/cm2. Twenty-four hours later, the erythema reaction was evaluated with LDF and LDI systems. There was a significant correlation between the logarithmic dose of UVB and erythema values. The curves consisted of two parts, an initial, flat phase and then a linear, steep one. Also, there was a good correlation between LDF and LDI. The LDI is as sensitive as conventional LDF, but has the many advantages of measuring blood flow over large areas without contact with the skin surface. This instrument will be useful in the measurement of skin blood flow in many areas of dermatological application.

Acute modulation of the extent of apoB mRNA editing and the relative rates of syntheses of apoB48 and apoB100 in cultured rat hepatocytes by osmotic and other stress stimuli

The mRNA for apolipoprotein B (apoB) is edited by the enzyme APOBEC-1, which acts as part of a multiprotein complex or editosome. In cultured rat hepatocytes obtained from fed animals this results in the presence of edited and unedited apoB mRNA in a ratio of approximately 3:2 in the basal state. In this study we show that hyper-osmotic media, which induce cell shrinkage, resulted in an acute increase in the degree of editing of apoB mRNA (hypo-osmotic conditions had no effect). This increase was accompanied by a parallel and highly positively correlated change in the ratio of the rate of synthesis of apoB48 relative to that of apoB100. These changes occurred in the absence of any changes in the overall APOBEC-1 mRNA levels, indicating that the activation of editing occurred at a post-transcriptional level. Levels of total apoB mRNA were also unaffected by hyper-osmotic exposure of the cells indicating that changes in the relative rates of synthesis of apoB48 and apoB100 were due to post/translational events. Exposure of cells to anisomycin at concentrations (50 micrograms/ml) that inhibit protein synthesis or to the transcriptional inhibitor actinomycin D produced changes in the degree of apoB mRNA editing that were similar to those given by hyper-osmotic shock indicating that editing is able to respond acutely to transcriptional or translational inhibition. Anisomycin, at concentrations (50 ng/ml) that activate SAPK/JNK but do not inhibit protein synthesis, gave only a fraction of the effect of hyper-osmotic shock. SB203580, an inhibitor of p38 kinase, did not attenuate the effects of hyper-osmotic conditions on APOBEC-1 editing. These observations suggest that these MAPkinase pathways play a relatively minor part in the transduction of the osmotic stimulus to the editing mechanism. The hyper-osmotically-induced increase in apoB mRNA editing was also insensitive to PD98059 and wortmannin (inhibitors of MEK and PI3 kinase, respectively). These data provide evidence that apoB mRNA editing is capable of acute modulation independently of transcriptional or translational mechanisms and suggest that one or more components of the editosome may undergo post-translational activation.

Importance of valine at position 152 for the substrate transport and 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane binding of dopamine transporter

Human and bovine dopamine transporters (DAT) demonstrate discrete functional differences in dopamine (DA), 1-methyl-4-phenylpyridium (MPP(+)) transport, and cocaine analog binding. In a previous study, the functional analyses on the chimeras of human and bovine DAT have revealed that the region from residues 133 through 186 (encompassing the third transmembrane domain) is responsible for the substrate transport and cocaine analog binding. The present study has been carried out to determine the specific amino acid(s) conferring DAT functions by interchanging the amino acid residues in the corresponding region between human and bovine DAT. As described previously, the DA, MPP(+) transport, and 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane (CFT) binding almost disappeared in chimera hb3 in which the region from residues 133 through 186 of bovine DAT was substituted into human DAT. Replacement of isoleucine, residue 152 of chimera hb3 (bovine DAT sequence), with valine, the human DAT residue at the identical position, remarkably restored the substrate transport and CFT binding to 76% to 98% of the human DAT values. Similarly, substitution of isoleucine for valine at position 152 in the human DAT reduced the substrate transport and CFT binding by 57% to 97%. Among other amino acids tested at position 152 of the chimera hb3, only alanine resulted in small but significant increases in the DAT functions ranging from 16 to 34%. Thus, valine at position 152 plays a crucial role for molecular mechanisms underlying the interactions of DA, MPP(+), and CFT with human DAT.

Murine bone marrow-derived mast cells exhibit evidence of both apoptosis and oncosis after IL-3 deprivation

IL-3 deprivation has been reported to induce apoptosis of bone marrow-derived mast cells. In order to evaluate this type of cell death further, we employed trypan blue and propidium iodide stainings, photometric enzyme immunoassay, fluorescence measurement of caspase-3, DNA electrophoresis, flow cytometry and transmission electron microscopy. In this experiment, although several evidences supporting apoptosis were demonstrated some findings were not consistent with typical apoptosis. On the other hand, electron microscopical observation demonstrated that most cells from all the time phases after IL-3 deprivation showed the morphology of typical oncosis, i.e. cell swelling, disintegration of ultrastructure and subsequent karyolysis. Only a small number of cells from the later time phases showed apoptotic morphology. We here suggest that BMMCs undergo both apoptosis and oncosis after IL-3 deprivation and that the dominant type of prelethal change is oncosis in all time phases, although apoptosis also plays a partial role in the late time phases.

A switch in the direction of the effect of insulin on the partitioning of hepatic fatty acids for the formation of secreted triacylglycerol occurs in vivo, as predicted from studies with perfused livers

The direct effects of insulin on hepatic triacylglycerol secretion are important because they may determine the degree of postprandial hyperlipidaemia, a known risk factor for the development of atherosclerotic lesions. Previous work from this laboratory, conducted on isolated perfused rat livers [Zammit, V.A., Lankester, D.J., Brown, A.M. & Park, B.S. (1999) Eur. J. Biochem. 263, 859-864], has indicated that the effect of insulin on hepatic triacylglycerol secretion is dependent on the prior physiological state of the donor animals. In this paper, we demonstrate that a switch in the direction of insulin action on hepatic partitioning of fatty acyl moieties towards triacylglycerol secretion also occurs in vivo between the fed, normoinsulinaemic state and the fasted or severely insulin-deficient states. The partitioning of fatty acids in the liver of awake, unstressed rats was studied using selective labelling of hepatic fatty acids during hyperinsulinaemic-euglycaemic clamps achieved through the use of hepatocyte-targeted liposome-encapsulated insulin preparations. The data show that, whereas in the fed, normoinsulinaemic state, insulinization of the liver raises the proportion of fatty acids directed towards secreted triacylglycerol, in the fasted or insulin-deficient states, insulin inhibits the partitioning of acyl moieties into secreted triacylglycerol. These data show that observations on the direction of insulin action on hepatic triacylglycerol secretion obtained using isolated perfused rat livers are reflected in the effects of the hormone on hepatic fatty acid partitioning in vivo. They offer an explanation for the positive relationship between chronic hyperinsulinaemia, hepatic VLDL-triacylglycerol secretion and hypertriglyceridaemia observed previously in insulin-resistant states.

Characterization of early and late onset psoriasis in the Korean population

It has been proposed that two types of psoriasis can be characterized based upon age of onset. The purpose of our study was to investigate the characteristics of early and late onset psoriasis in the Korean population. A total of 986 psoriasis patients were included in this study, and the age of onset frequency proved to be bimodal. Family history in the first-degree relatives was significantly higher in the early onset group (< 40 years old) when compared with the late onset group (> or = 40 years old). A series of statistical analyses concerning the correlation between the extent of involvement and age of onset showed that earlier onset is related to more extensive involvement. A questionnaire survey concerning the influence of various external factors upon their psoriasis was given to a subgroup of 800 psoriasis patients. Multiple logistic regression analysis, controlled for confounding factors such as current age, sex and extent of involvement, revealed that early onset psoriasis patients showed significantly increased tendencies to worsen at times of psychological stress and in winter, and to improve in summer, compared with late onset psoriasis patients. In conclusion, distribution of the age of onset revealed two peaks in Korean psoriasis patients, and psoriasis with an onset prior to the age of 40 years was associated with increased inheritability, greater susceptibility to seasonal changes and more psychological stress than psoriasis with later onset.

Insulin stimulates triacylglycerol secretion by perfused livers from fed rats but inhibits it in livers from fasted or insulin-deficient rats implications for the relationship between hyperinsulinaemia and hypertriglyceridaemia

We determined whether the direction of the acute effect of insulin on hepatic triacylglycerol secretion is dependent on the prior physiological state or on the in vitro experimental system used. The effect of insulin on triacylglycerol secretion was studied using perfused livers isolated from rats under three metabolic conditions: fed normo-insulinaemic, 24-h fasted and fed, streptozotocin-diabetic (insulin-deficient). Insulin acutely activated triacylglycerol secretion (by 43%) in organs from fed, normo-insulinaemic animals, whereas it inhibited triacylglycerol secretion in livers isolated from fasted or insulin-deficient rats (by 30 and 33%, respectively). By contrast, in 24-h-cultured hepatocytes insulin invariably acutely inhibited triacylglycerol secretion irrespective of the metabolic state of the donor animals. It is concluded that the use of perfused livers enables the observation of a switch in the direction of insulin action on hepatic triacylglycerol secretion from stimulatory, in the normo-insulinaemic state, to inhibitory in the fasting or insulin-deficient state. The possible implications of this switch for the relationship between hyperinsulinaemia, increased hepatic very-low-density lipoprotein-triacylglycerol secretion and hypertriglyceridaemia observed in vivo are discussed.

Vitamin D receptor polymorphism is associated with psoriasis

Vitamin D receptor is a trans-acting transcriptional factor that mediates 1alpha,25-dihydroxyvitamin D3 action in the regulation of target gene expression. Recent studies have shown that clinical response of psoriasis to 1alpha,25-dihydroxyvitamin D3 is correlated with the vitamin D receptor mRNA expression level, which may be influenced by the genotype of the vitamin D receptor. In this study, we have explored a possible association between psoriasis and the polymorphism in the gene encoding the vitamin D receptor. We examined the allelic frequencies of the vitamin D receptor in psoriasis patients (n = 104) and in healthy controls (n = 104) by analyzing the restriction pattern of the polymerase chain reaction products. A significant increase in the frequency of the A allele (absence of the restriction site at intron 8) by ApaI restriction fragment length polymorphism was observed in psoriasis patients compared with that of the control group, and the tendency was more accentuated in early onset psoriasis. Odds ratios (95% confidence interval) for psoriasis of AA and Aa genotypes were 5.0 (1.3-19.1) and 2.4 (1.3-4.3), and odds ratios for early onset of AA and Aa genotypes were 6.4 (1.6-25.0) and 3.1 (1.7-5.9), respectively. Allele frequencies for A and a alleles were 0.317 and 0.683 in the psoriasis group and 0.168 and 0.832 in the control group (p = 0.001). A significant association between vitamin D receptor genotypes and the mean age at onset was observed (p < 0.05). Our findings suggest that allelic variance in the vitamin D receptor gene itself or other genes in linkage disequilibrium with this gene, could predispose to the development of psoriasis.

Dermal dendrocytes participate in the cellular pathology of experimental acute graft-versus-host disease

In a well established murine model relevant to human disease, graft-versus-host disease results from recognition of recipient minor histocompatibility antigens by donor bone marrow-derived T lymphocytes. Previous studies suggest that factor XIIIa-positive dermal dendrocytes may be involved in the pathogenesis of disorders involving antigen presentation to T cells and dermal fibrosis. This study was undertaken to determine (i) whether normal murine skin contains factor XIIIa-positive dermal dendrocytes, and (ii) whether such cells participate in the pathophysiology of acute graft-versus-host disease. Graft-versus-host disease was produced using B10.BR CD8+ donor T cells administered to CBA recipients. Skin samples were collected weekly for a 5-week period and evaluated by immunohistochemistry and electron microscopy. Our data indicate that normal murine dermis contains factor XIIIa-positive cells localized primarily around deep dermal microvessels. Ultrastructural analyses reveal these cells to have long processes, pinocytotic vesicles, fibronexuses, and intimate associations with mast cells. During graft-versus-host disease, factor XIIIa-positive dendrocytes appeared within the superficial dermis. By ultrastructure, the dendrocytes were hypertrophic and highly branched, and demonstrated an intimate relationship with neighboring cells. In conclusion, factor XIIIa-positive dendrocytes comprise a normal component of the murine dermis and undergo alterations in experimental acute graft-versus-host disease consistent with participation in disease pathophysiology.

Cloning and expression of a novel gene encoding a new antibacterial peptide from silkworm, Bombyx mori

We differentially screened a novel gene encoding a new antibacterial peptide from the immunized Bombyx mori cDNA library. The gene showed a similar structure to that of cecropin-family, encoding 59 amino acids including a putative leader peptide and mature peptide. The deduced peptide, named Enbocin, had conserved amino acid residues which have been known to play an important role in the antibacterial activities. Enbocin genomic sequence revealed that the transcription unit of Enbocin gene was about 1.2 kb, and the coding sequence was interrupted by an intron of 660 bases. Recombinant Enbocin, expressed under the control of the baculovirus polyhedrin promoter, demonstrated a broad range of antibacterial activities against gram positive and gram negative bacteria.

Factors influencing psoriasis: an analysis based upon the extent of involvement and clinical type

A variety of external stimuli are accepted as important in modifying the severity of psoriasis. We sought to determine whether there is any difference in the influence of external factors on psoriasis in relation to extent of involvement or clinical type. A total of 870 psoriasis patients seen between 1982 and 1995 were categorized as mild, moderate, or severe on the basis of extent of the disease, and as guttate, nummular/plaque, or exfoliative/generalized pustular according to clinical type. We then performed a questionnaire survey concerning the influence of external factors such as seasonal changes, sunlight, stress, and pregnancy. These data sets were combined and analysed. The majority of patients stated favorable effects of summer, sunlight, and pregnancy and adverse effects of winter and stress. A statistically significant correlation was noted between the extent of psoriasis and the proportion of patients stating that their disease worsened at times of psychological stress (p < 0.01). We confirmed that psoriasis patients with more extensive involvement experience greater fluctuations in their condition, notice these changes, and therefore relate them to psychological stress.

Planar gradient coil design by scaling the spatial frequencies of minimum-inductance current density

Gradient coil inductance has been remarkably reduced by the minimum-inductance design technique, which minimizes the magnetic energy stored by the gradient coil. The planar gradient coil designed by this technique, however, often has poor magnetic field linearity. Scaling the spatial frequencies of the current density function derived by this method, the magnetic field linearity of the planar gradient coil can be greatly improved with a small sacrifice of gradient coil inductance. A figure of merit of the planar gradient coil has been found to be improved by scaling the spatial frequencies.

Malignant proliferating trichilemmal tumor showing distant metastases

We describe a case of malignant proliferating trichilemmal tumor showing multiple distant metastases. For 10 years, the patient had had a round mass in the occiput, which recurred twice after wide excisions, and later metastasized to the cervical lymph nodes, periparotid area, and chest. Each time the lesions were excised, histologic specimens demonstrated a proliferating trichilemmal tumor with increasing nuclear atypia. Serial specimens showed increasing Ki-67 positivity as the extent of the tumor advanced.

Disseminated superficial porokeratosis in a patient with chronic liver disease

A 55-year-old male suffering from liver cirrhosis presented with diffuse annular hyperkeratotic papules of abrupt onset on the trunk and extremities. Histopathologic examination revealed cornoid lamella and eosinophilic spongiosis. He did not receive any medications other than cephalosporin for spontaneous bacterial peritonitis. A review of the literature revealed that three cases developed porokeratosis when their liver function declined and that, in one case, the porokeratosis disappeared spontaneously with liver transplantation. Although the precise mechanism is unclear, there is evidence demonstrating immunoincompetence in cirrhosis. Even though we did not perform immunologic studies or exclude the possibility of drug-induced porokeratosis in our case, it is conceivable that porokeratosis can be triggered by immunosuppression due to liver cirrhosis per se.

Photoprotective effect of calcipotriol upon skin photoreaction to UVA and UVB

It has been shown that 1,25-dihydroxyvitamin D3 has a photoprotective effect against UVB injury in mouse skin and cultured rat keratinocytes by induction of metallothionein (MT). Calcipotriol is a synthetic analogue of 1,25-dihydroxyvitamin D3 with equipotent cell regulating properties, but with a lower risk of calcium-related side effects. The aim of the present study was to see whether calcipotriol has a photoprotective property both in vitro and in vivo. We examined the effect of calcipotriol on UV-induced damage of cultured human keratinocytes through a cell viability assay, and measurement of DNA synthesis by cultured keratinocytes, on UV-induced damage of mouse skin and on minimal erythema dose (MED). We found that calcipotriol was protective against UVB-induced reduction in DNA synthetic activity of cultured keratinocytes in relatively low doses (20 and 40 mJ/cm2) of UVB. With phototesting following application of calcipotriol, five subjects among 10 healthy volunteers and three among six psoriasis patients showed an increase in MED compared with the vehicle-treated site. These findings imply that calcipotriol may be photoprotective and that more extensive studies with various doses of UV irradiation and modes of calcipotriol delivery are required.

Promoter sequences of two homologous pectin esterase genes from Chinese cabbage (Brassica campestris L. ssp. pekinensis) and pollen-specific expression of the GUS gene driven by a promoter in tobacco plants

The promoter regions of two genomic clones, GBAN215-6 and GBAN215-12 from Chinese cabbage (Brassica campestris L. ssp. pekinensis), were sequenced. The nucleotide sequences of their promoter regions were compared with that of the Bp19 pollen-specific gene of Brassca napus. High nucleotide sequence homologies were observed among these three genes in the region between 210 bp upstream and the putative transcription start site. A sequence motif TGTGGTG, which is similar to that of the PB core motif (TGTGGTT) of two tomato pollen-specific genes, LAT52 and LAT56, was present in these two cloned genes. To determine regulatory sequences responsible for the anther-specific expression of the gene BAN215-6, two recombinant plasmids, pBPE3 (-274- + 109) and pBPE4 (-816- + 109) containing different lengths of the promoter fused with the GUS gene, were constructed and introduced into tobacco plants by Agrobacterium-mediated transformation. The result showed that the 383 bp (-274- + 109) of the BAN215-6 promoter region was sufficient for the anther-specific expression of the GUS gene. The GUS expression in a tobacco plants transformed with these constructs was first detected in uninucleate microspores and persisted at in vitro germinated pollen tubes. The expression level was increased during anther development, reaching the highest level in mature pollens.

Mutations of the tyrosinase gene in three Korean patients with type I oculocutaneous albinism

Oculocutaneous albinism (OCA) is an inherited disorder of the melanin pigmentary system, characterized by a decrease or an absence of melanin in the skin, hair, and eyes. Type I (tyrosinase-deficient) OCA results from mutations of the tyrosinase (TYR) gene encoding tyrosinase, the enzyme that catalyzes at least the first two steps of melanin biosynthesis. We have analyzed the TYR gene in three Korean patients with severe type I OCA. Two patients were compound heterozygotes for the Arg (CGG) to Gln (CAG) mutation at position 77 and a C insertion mutation at position 310. The other was a compound heterozygote for a C insertion mutation at position 310 and the Asp (GAT) to Asn (AAT) mutation at position 383. These mutations were easily detected by restriction enzyme digestion or by SSCP analysis. Such methods of mutation analysis thus provide a basis for a screening system for the TYR gene mutations in Korean patients with type I OCA.

Quantification in vivo of the effects of different types of dietary fat on the loci of control involved in hepatic triacylglycerol secretion

Polyunsaturated fatty acids (PUFA) have been suggested to exert their hypotriglyceridaemic effect through several possible mechanisms that would be expected to decrease the rate of hepatic very-low-density-lipoprotein-triacylglycerol secretion. We have quantified the role played in vivo by changes in the pattern of partitioning of (i) acyl-CoA between oxidation and esterification, (ii) diacylglycerol between synthesis of triacylglycerol and of the major phospholipids, and (iii) triacylglycerol between secretion and storage within the liver, in response to two dietary levels of n-6 and n-3 PUFA. In order to achieve this we used the technique of selective labelling of hepatic fatty acids in vivo. Compared with a predominantly saturated fatty acid diet, both n-6 and n-3 PUFA intake resulted in a decrease in the proportion of acyl moieties that were secreted by the liver, through an increased diversion of acyl-CoA towards oxidation and a lower fractional rate of secretion of newly synthesized triacylglycerol. In addition, a diet rich in n-3 fatty acids resulted not only in a greater magnitude of these effects but also in a doubling of the partitioning of diacylglycerol towards phospholipid labelling. It is shown that the overall 50% reduction achieved by fish oil feeding in the proportion of acyl groups that were secreted by the liver was distributed over all three branch points. The contribution of each of these adaptations was quantified. The application of such an approach, i.e. the localization and in vivo quantification of the importance of loci of control, in studies on dietary and pharmacological agents that affect lipaemia, is discussed.

Delay of explosive vaporization in pulsed laser-heated droplets

Measurements of time delays for explosion of pulsed CO(2) laser-heated droplets are presented. A simple model based on classical nucleation theory in superheated liquids, which neglects heat and mass transport, is used to interpret the data. The model shows good agreement with the experimental observations.

Laser heating of droplets with absorbing core

The irradiation and heating of a spherical droplet containing an absorbing core are studied numerically using a corrected surface energy balance.

Effect of phosphatidylcholine on the alpha-lactalbumin-induced fusion of vesicles

Previous studies on alpha-lactalbumin induced fusion of phosphatidylserine/phosphatidylethanolamine vesicles are extended to vesicles composed of various combinations of phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine and cardiolipin. It was found that inclusion of phosphatidylcholine in the vesicles results in a depression of fusion. This depression of fusion appears to be caused by a reduction in the amount of irreversibly bound alpha-lactalbumin to vesicles containing phosphatidylcholine. It is suggested that in this system fusion is dependent upon the extent by which a particular protein segment penetrates the bilayer.