Type-II Red Phosphorus: Wavy Packing of Twisted Pentagonal Tubes

Elemental phosphorus exhibits fascinating structural varieties and versatile properties. The unique nature of phosphorus bonds can lead to the formation of extremely complex structures, and detailed structural information on some phosphorus polymorphs is yet to be investigated. In this study, we investigated an unidentified crystalline phase of phosphorus, type-II red phosphorus (RP), by combining state-of-the-art structural characterization techniques. Electron diffraction tomography, atomic-resolution scanning transmission electron microscopy (STEM), powder X-ray diffraction, and Raman spectroscopy were concurrently used to elucidate the hidden structural motifs and their packing in type-II RP. Electron diffraction tomography, performed using individual crystalline nanowires, was used to identify a triclinic unit cell with volume of 5330 Å3 , which is the largest unit cell for elemental phosphorus crystals up to now and contains approximately 250 phosphorus atoms. Atomic-resolution STEM imaging, which was performed along different crystal-zone axes, confirmed that the twisted wavy tubular motif is the basic building block of type-II RP. Our study discovered and presented a new variation of building blocks in phosphorus, and it provides insights to clarify the complexities observed in phosphorus as well as other relevant systems.

Negative Valley Polarization of the Intralayer Exciton via One-Step Growth of H-Type Heterobilayer WS2/MoS2

Vertical type II van der Waals heterobilayers of transition metal dichalcogenides (TMDs) have attracted wide attention due to their distinctive features mostly arising from the emergence of intriguing electronic structures that include moiré-related phenomena. Owing to strong spin-orbit coupling under a noncentrosymmetric environment, TMD heterobilayers host nonequivalent +K and -K valleys of contrasting Berry curvatures, which can be optically controlled by the helicity of optical excitation. The corresponding valley selection rules are well established by not only intralayer excitons but also interlayer excitons. Quite intriguingly, here, we experimentally demonstrate that unusual valley switching can be achieved using the lowest-lying intralayer excitons in H-type heterobilayer WS₂/MoS₂ prepared by one-step growth. This TMD combination provides an ideal case for interlayer coupling with an almost perfect lattice match, thereby also in the momentum space between +K and -K valleys in the H-type heterostructure. The underlying valley-switching mechanism can be understood by bright-to-dark conversion of initially created electrons in the valley of WS₂, followed by interlayer charge transfer to the opposite valley in MoS₂. Our suggested model is also confirmed by the absence of valley switching when the lowest-lying excitons in MoS₂ are directly generated in the heterobilayer. In contrast to the H-type case, we show that no valley switching is observed from R-type heterobilayers prepared by the same method, where interlayer charge transfer does not occur between the opposite valleys. We compare the case with the series of valley polarization data from other heterobilayer combinations obtained under different excitation energies and temperatures. Our valley switching mechanism can be utilized for valley manipulation by controlling the excitation photon energy together with the photon helicity in valleytronic devices derived from H-type TMD heterobilayers.

Pilot study of fractional microneedling radiofrequency for hidradenitis suppurativa assessed by clinical response and histology

BACKGROUND

Hidradenitis suppurativa (HS) is a devastating chronic inflammatory skin disease with frequent recurrences. Various systemic treatments and procedures have been used but the efficacy of fractional microneedling radiofrequency (FMR) has not been reported.

AIM

To evaluate the clinical and histological efficacy of FMR in the treatment of HS lesions.

METHODS

An 8-week, prospective, split-body, unblinded study was conducted, which enrolled 10 adult patients with mild to moderate HS to receive 3 sessions of FMR treatment biweekly. HS severity was assessed using the number and type of lesions, HS Physician Global Assessment (HS-PGA) and the modified Sartorius score (mSS). Skin biopsies were performed on participants to assess change in inflammation before and after FMR.

RESULTS

Severity of HS was significantly reduced on the FMR-treated side of the body, but not on the control side. Inflammatory HS lesions were significantly reduced after 4 weeks, while HS-PGA and mSS were significantly decreased after 6 weeks. Immunohistochemistry staining showed decreased expression of inflammatory markers including neutrophil elastases, interleukin (IL)-8 and IL-17, tumour necrosis factor-α, transforming growth factor-β1 and matrix metalloproteinases.

CONCLUSION

FMR may be a viable treatment option for mild to moderate HS.

Fabrication and Imaging of Monolayer Phosphorene with Preferred Edge Configurations via Graphene-Assisted Layer-by-Layer Thinning

Phosphorene, a monolayer of black phosphorus (BP), is an elemental two-dimensional material with interesting physical properties, such as high charge carrier mobility and exotic anisotropic in-plane properties. To fundamentally understand these various physical properties, it is critically important to conduct an atomic-scale structural investigation of phosphorene, particularly regarding various defects and preferred edge configurations. However, it has been challenging to investigate mono- and few-layer phosphorene because of technical difficulties arising in the preparation of a high-quality sample and damages induced during the characterization process. Here, we successfully fabricate high-quality monolayer phosphorene using a controlled thinning process with transmission electron microscopy and subsequently perform atomic-resolution imaging. Graphene protection suppresses the e-beam-induced damage to multilayer BP and one-side graphene protection facilitates the layer-by-layer thinning of the samples, rendering high-quality monolayer and bilayer regions. We also observe the formation of atomic-scale crystalline edges predominantly aligned along the zigzag and (101) terminations, which is originated from edge kinetics under e-beam-induced sputtering process. Our study demonstrates a new method to image and precisely manipulate the thickness and edge configurations of air-sensitive two-dimensional materials.

Atrophic acne scar: a process from altered metabolism of elastic fibres and collagen fibres based on transforming growth factor-β1 signalling

BACKGROUND

Atrophic acne scar, a persistent sequela from acne, is undesirably troubling to many patients due to its cosmetic and psychosocial aspects. Although there have been some reports emphasizing the role of early inflammatory responses in atrophic acne scarring, evolving perspectives on the detailed pathogenic processes are promptly needed.

OBJECTIVES

Examining the histological, immunological and molecular changes in early acne lesions susceptible to atrophic scarring can provide new insights to understand the pathophysiology of atrophic acne scar.

METHODS

We experimentally validated several early fundamental hallmarks accounting for the transition of early acne lesions to atrophic scars by comparing molecular profiles of skin and acne lesions between patients who were prone to scar (APS) or not (ANS).

RESULTS

In APS, compared with ANS, devastating degradation of elastic fibres and collagen fibres occurred in the dermis, followed by their incomplete recovery. Abnormally excessive inflammation mediated by innate immunity with T helper 17 and T helper 1 cells was observed. Epidermal proliferation was significantly diminished. Transforming growth factor (TGF)-β1 was drastically elevated in APS, suggesting that aberrant TGF-β1 signalling is an underlying modulator of all of these pathological processes.

CONCLUSIONS

These results may provide a basis for understanding the pathogenesis of atrophic acne scarring. Reduction of excessive inflammation and TGF-β1 signalling in early acne lesions is expected to facilitate the protection of normal extracellular matrix metabolism and ultimately the prevention of atrophic scar formation. What's already known about this topic? The dermis of atrophic acne scars shows alteration of extracellular matrix components such as collagen fibres. Inflammation in acne lesions is associated with the development of acne scars. What does this study add? Abnormalities in the metabolism of collagen fibres and elastic fibres were observed in the early developmental stages of acne lesions that were progressing into atrophic scars. Exacerbated inflammation and aberrant epidermal proliferation by increased transforming growth factor (TGF)-β1 signalling may affect the abnormal extracellular matrix metabolism. What is the translational message? Abnormal changes in elastic fibres and collagen fibres are found in the early developmental process of acne in patients who are prone to atrophic scarring. An early treatment regimen strongly inhibiting inflammation and TGF-β1 signalling to help the normal recovery of the extracellular matrix components is required to prevent atrophic scarring.

Predictive value of a fragmented QRS complex in diagnosing patients with myocardial ischemia

Background

A fragmented QRS complex (fQRS) is caused by conduction abnormalities of the ventricle secondary to myocardial ischemia and/or scar in patients with myocardial infarction. However, the implications of the fQRS in the development of coronary artery disease with myocardial ischemia in those without a scar remain unknown.

Methods

We studied electrocardiograms (ECGs) obtained from 150 patients (60.5 ± 8.5 years, 102 men) with myocardial ischemia, which was confirmed by performing both, a nuclear exercise stress test and coronary angiography. We also studied ECGs obtained from 601 patients (58.5 ± 10.0 years, 315 men) who showed a negative nuclear exercise stress test (control group). Patients in whom the nuclear exercise stress test showed a myocardial scar were excluded.

Results

An fQRS was more commonly observed in patients with myocardial ischemia (n = 48, 32.0%) than in the control group (n = 133, 22.1%) (P = 0.011). The sensitivity, specificity, positive, and negative predictive values of fQRS in diagnosing myocardial ischemia were 32.0, 77.9, 26.5, and 82.1%, respectively. The fQRS (odds ratio 1.580, 95% confidence interval 1.020‐2.446, P = 0.040) was an independent predictor of myocardial ischemia after adjusting for age, sex, current smoking habits, ST‐T changes on ECG, as well as histories of hypertension, diabetes, and dyslipidemia. Moreover, the fQRS showed an incremental prognostic value over conventional risk factors (χ² = 5, P = 0.032) and over a combination of conventional factors and ST‐T changes (χ² = 9, P = 0.014).

Conclusions

The fQRS is a moderately sensitive and independent predictor of myocardial ischemia.

One-Dimensional Assembly on Two-Dimensions: AuCN Nanowire Epitaxy on Graphene for Hybrid Phototransistors

The van der Waals epitaxy of functional materials provides an interesting and efficient way to manipulate the electrical properties of various hybrid two-dimensional (2D) systems. Here we show the controlled epitaxial assembly of semiconducting one-dimensional (1D) atomic chains, AuCN, on graphene and investigate the electrical properties of 1D/2D van der Waals heterostructures. AuCN nanowire assembly is tuned by different growth conditions, although the epitaxial alignment between AuCN chains and graphene remains unchanged. The switching of the preferred nanowire growth axis indicates that diffusion kinetics affects the nanowire formation process. Semiconducting AuCN chains endow the 1D/2D hybrid system with a strong responsivity to photons with an energy above 2.7 eV, which is consistent with the bandgap of AuCN. A large UV response (responsivity ∼10⁴ A/W) was observed under illumination using 3.1 eV (400 nm) photons. Our study clearly demonstrates that 1D chain-structured semiconductors can play a crucial role as a component in multifunctional van der Waals heterostructures.

Evaluation of abundance of artificial radionuclides in food products in South Korea and sources

Food samples are collected nationwide from January 2016 to February 2017 and their contents of artificial radionuclides are measured to address the growing concerns regarding the radioactive contamination of food products in Korea. Specifically, 900 food samples are collected for this study and their contents of representative artificial radionuclides ¹³⁴Cs, ¹³⁷Cs, ^239,240Pu, and ⁹⁰Sr are analyzed. The analysis shows that the activity concentrations of ¹³⁷Cs in fish range from minimum detectable activity (MDA) to 340 mBq/kg of fresh weight. The concentration factor (CF) determined for ¹³⁷Cs as a measure of its bioavailability is calculated to be ca. 74 and found to be very similar to that (100) recommended by the International Atomic Energy Agency. With an MDA of <0.221 mBq/kg, the results reveal that ^239,240Pu values in fish are below the MDA. The activity concentrations of ¹³⁷Cs and ⁹⁰Sr are lower than the MDA in both shellfish and seaweed, while the activity concentrations of ^239,240Pu in shellfish range from 0.26 to 2.18 mBq/kg, and for seaweed samples range from 2.07 to 3.38 mBq/kg. The atom ratios of ²⁴⁰Pu/²³⁹Pu in shellfish caught at the Korean coast vary from 0.209 to 0.237, with a mean of 0.227. The higher ²⁴⁰Pu/²³⁹Pu atom ratio determined in shellfish is thought to be caused by the plutonium transported from the Pacific Proving Grounds rather than other sources such as the Fukushima nuclear power plant accident. The activity concentrations of ¹³⁷Cs in mushrooms are found to vary from 1.0 to 21.4 Bq/kg, with the highest concentrations observed in the Oak (shiitake) and Sarcodon asparatus. ¹³⁴Cs is detected in three mushroom specimens collected from Jeju Island and about 3-3.6% of ¹³⁷Cs present in the wild mushrooms native to the Jeju Island are introduced as a result of the Fukushima nuclear plant accident. The annual effective doses of ¹³⁷Cs received through consumption of mushrooms and fish are 2.0 × 10^-4 mSv yr^-1 and 3.9 × 10^-5 mSv yr^-1, and those values are negligible compared to the annual effective doses limit of 1 mSv yr^-1.

Epidemiology and risk factors of childhood acne in Korea: a cross-sectional community based study

BACKGROUND

The epidemiology of acne vulgaris appears to be evolving, with an increasingly earlier onset seen in childhood. Relevant studies have been rarely performed in Asia.

AIM

We sought to estimate the prevalence and clinical characteristics of acne among schoolchildren, and its association with treatment-seeking behaviour, body mass index (BMI), nutritional habits and other lifestyle elements.

METHODS

A cross-sectional study was conducted with elementary schoolchildren aged 7-12 years. Children were interviewed by self-administered questionnaires, and were subsequently evaluated by dermatologists.

RESULTS

Of 693 children enrolled, 36.2% were diagnosed with acne, and the prevalence increased with age. Additionally, clinical characteristics including severity, duration of disease and lesion distribution were significantly different between the lower (aged 7-9 years) and the higher (aged 10-12 years) grades. Subjective features including recognition about acne and treatment-seeking behaviours were also different between the two groups. Overweight or obesity (BMI ≥ 25 kg/m(2) at 18 years of age; OR = 2.7) and consumption of chocolates/sweets (OR = 1.6) were significant risk factors for acne.

CONCLUSIONS

In the current study, the prevalence of acne among elementary schoolchildren was high, but only a few children had received treatment. Physicians should be attentive to childhood acne, and educate patients and their parents about the need to treat it.

First Report of Cucumber mosaic virus in Saintpaulia ionantha in Korea

African violet (Saintpaulia ionantha) is an ornamental species of the family Gesneriaceae and is characterized by fleshy leaves and colorful flowers. This popular, exotic ornamental, originally from Kenya and Tanzania, is vegetatively produced from cutting and tissue culture (1). In May 2013, virus-like foliar symptoms, including a mosaic with dark green islands and chlorosis surrounding the veins, were observed on an African violet plant in a greenhouse located in Icheon, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with a commercial immunostrip kit (Agdia, Elkhart, IN). The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-AV1) caused necrotic local lesions on Chenopodium amaranticolor at 5 days post-inoculation (dpi), while mild to severe mosaic was observed in Nicotiana glutinosa, N. tabacum 'Samsun NN,' Cucurbita pepo 'Super-Top,' Physalis angulate, and Solanum lycopersicum 'Unicorn' 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions ∼28 nm in diameter, respectively. To verify whether CMV-AV1 is the cause of disease symptoms observed in African violet, virus-free African violet (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-AV1. At 8 weeks after inoculation, all plants produced systemic mosaic and chlorosis surrounding veins, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated African violet plants remained symptomless and virus-free. The presence of CMV-AV1 in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany), according to the manufacturer's instructions. RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CPTALL3 and CPTALL5 (2), amplifying the entire CP gene and part of an intergenic region and 3'-noncoding region of CMV RNA3. RT-PCR products (960 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen) and sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-AV1 CP sequence (Accession No. AB842275) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-AV1 infection. CMV may pose a major threat for production of African violet since the farming of African violet plants is performed using the vegetative propagation of the African violet leaves in Korea. In particular, mosaic and chlorosis symptoms in African violet cause damage to ornamental quality of African violet. To our knowledge, this is the first report of CMV infection of African violet in the world. References: (1) S. T. Baatvik. Fragm. Flor. Geobot. Suppl. 2:97, 1993. (2) S. K. Choi et al. J. Virol. Methods 83:67, 1999.

Double-blind, randomized non-inferiority trial of a novel botulinum toxin A processed from the strain CBFC26, compared with onabotulinumtoxin A in the treatment of glabellar lines

BACKGROUND

Botulinum toxins have been widely used in cosmetic dermatology. Neurotoxin from the CBFC26 strain (NTC) is a recently developed botulinum toxin type A product manufactured through refined procedures.

OBJECTIVE

A double-blinded, randomized, multicentre-designed, phase III trial to investigate the non-inferiority of NTC to existing botulinum toxin A, onabotulinumtoxin A in the treatment of moderate to severe glabellar lines.

METHODS

A total of 272 subjects were randomized in a 1 : 1 ratio to receive 20 U of NTC or onabotulinumtoxin A. The primary endpoint was the response rate of physicians' assessment (PA) using the Facial Wrinkle Scale at week 4. The secondary endpoints included the response rate of PA at weeks 8, 12 and 16, and photographic assessment at weeks 4, 8, 12 and 16. Subjects' improvement assessment and subjective self-satisfaction levels were also investigated.

RESULTS

Response rates for maximum frown were 89.3% in the NTC group and 81.9% in the onabotulinumtoxin A group at week 4. NTC also resulted in comparable results for both the response rates of the other evaluation points and incidence of adverse events compared to those of onabotulinumtoxin A. In subjects' improvement assessment and photographic evaluations, NTC even demonstrated better results compared with onabotulinumtoxin A in the early phase after treatment. Analysis of these results strongly supports the non-inferiority of NTC to onabotulinumtoxin A in the efficacy and safety.

CONCLUSION

NTC is as effective as onabotulinumtoxin A in the treatment of glabellar lines, and both products were well tolerated.

Fungal peri-prosthetic joint infection after primary total knee replacement

We retrospectively reviewed 30 two-stage revision procedures in 28 patients performed for fungal peri-prosthetic joint infection (PJI) after a primary total knee replacement. Patients were followed for at least two years or until the infection recurred. The mean follow-up for patients who remained free of infection was 4.3 years (2.3 to 6.1). Overall, 17 patients were assessed as American Society of Anesthesiologists grade 3 or 4. The surgical protocol included removal of the infected implant, vigorous debridement and insertion of an articulating cement spacer. This was followed by at least six weeks of antimicrobial treatment and delayed reimplantation in all patients. The mean interval between removal of the prosthesis and reimplantation was 9.5 weeks (6 to 24). After reimplantation, patients took antifungal agents orally for a maximum of six months. Two knees became reinfected at one and two months post-operatively, respectively: one of these subsequently required arthrodesis because of uncontrolled infection. Fungal PJIs can be treated successfully by removal of all infected material, appropriate antimicrobial treatment and delayed reimplantation.

Femoral lengthening in achondroplasia: magnitude of lengthening in relation to patterns of callus, stiffness of adjacent joints and fracture

Extensive limb lengthening may be indicated in achondroplastic patients who wish to achieve a height within the normal range for their population. However, increasing the magnitude of lengthening is associated with further complications particularly adjacent joint stiffness and fractures. We studied the relationship between the magnitude of femoral lengthening and callus pattern, adjacent joint stiffness and fracture of the regenerate bone in 40 femoral lengthenings in 20 achondroplastic patients. They were divided into two groups; group A had lengthening of less than 50% and group B of more than 50% of their initial femoral length. The patterns of radiological callus formation were classified according to shape, type and features. The incidence of callus features, knee stiffness and regenerate bone fracture were analysed in the two groups. Group B was associated with an increased incidence of concave, lateral and central callus shapes, adjacent joint and stiffness and fracture. Statistically, the incidence of stiffness in adjacent joints and regenerate bone fracture was significantly associated with the magnitude of lengthening. We suggest that careful radiological assessment of the patterns of callus formation is a useful method for the evaluation and monitoring of regenerate bone.

The complete genome sequence of pepper severe mosaic virus and comparison with other potyviruses

The complete nucleotide sequence of pepper severe mosaic virus (PepSMV) was determined. The viral genome consisted of 9890 nucleotides, excluding a poly (A) tract at the 3' end of the genome. The PepSMV RNA genome encoded a single polyprotein of 3085 amino acid residues, resulting in ten functionally distinct potyviral proteins. The lengths of the 5' nontranslated region (NTR) and the 3' NTR were 164 and 468 nucleotides, respectively. The genome organization of the virus was typical for members of the genus Potyvirus in the family Potyviridae. The coat protein amino acid sequence identity between PepSMV and the other 45 potyviruses ranged from 53.4 to 79.7%. Sequence alignments and phylogenetic analyses of the potyviral polyprotein sequences revealed that PepSMV was the closest to potato virus Y (PVY) and closely related to members of the PVY subgroup. Our genome sequence data clearly confirmed that PepSMV belongs to a separate species in the genus Potyvirus.

Duration curve analysis for the assessment of pathogen loading from diffuse sources

Pathogen level of surface waters has received great attention for protecting public health. In this study, total coliform, fecal coliform and Escherichia coli concentrations were monitored as the pathogen indicator organisms at six monitoring stations in the Geum River, Korea. Rainfall runoff from two agricultural-forestry watersheds was analyzed for their microbial aspect as well. Total coliform concentration of the Geum River showed high correlation with the flow rate. To estimate total coliform loading on the Geum River in probability scale, the duration curve method was applied. In addition, a standard duration curve reflecting the water quality criteria was constructed to determine water quality compliance. Under the assumption of linearity between flow rate and total coliform concentration of the Geum River, total coliform duration curve revealed that total coliform concentrations exceed the desired criteria mainly due to pollutants from diffuse sources.

Zantedeschia mosaic virus causing leaf mosaic symptom in calla lily is a new potyvirus

Anovel virus, Zantedeschia mosaic virus (ZaMV-KR), causing mosaic and malformation symptoms was isolated from calla lily ( Zantedeschia spp.) in Korea and its biological and molecular properties were characterized. The virus was distinct from Dasheen mosaic virus, an Araceae-infecting potyvirus, by serological and sequence analyses. Multiple alignments of the CP amino acid sequence between the virus and other potyviruses showed 51.8 to 62.1% identity. Phylogenetic analyses of the CP revealed that the virus could be clustered with Plum pox virus and Turnip mosaic virus. Sequence comparison of the CP gene between the virus and three other ZaMV isolates from Taiwan showed over 93.9% identity, and most of amino acids changes occurred in the N-terminal region. Sequence comparison of 3' NTR revealed homology levels of 27.0 to 47.9% between the virus and other potyviruses. Our results support ZaMV as a distinct species of the genus Potyvirus.

Completion of nucleotide sequence and generation of highly infectious transcripts to cucurbits from full-length cDNA clone of Kyuri green mottle mosaic virus

The nucleotide sequence of the genome of the type strain of Kyuri green mottle mosaic virus (KGMMV-C1) has been completely determined. The genome structure and sequence of the virus were compared to those of Yodo strain of KGMMV (KGMMV-Y). The genome of KGMMV-C1 is 6,514 nucleotides long consisting of 5' and 3' nontranslated regions (NTRs) and four open reading frames coding for 131 kDa and 189 kDa viral replicases, 28 kDa movement protein and 17 kDa coat protein. The nucleotide and amino acid sequences identities of the four encoded proteins and two NTRs between KGMMV-C1 and KGMMV-Y were 85.6% to 93.9% and 87.6% to 95.5%, respectively. Full-length cDNA of KGMMV-C1 was directly amplified by reverse-transcription polymerase chain reaction (RT-PCR) with a set of S'-end primer anchoring T7 RNA promoter sequence and 3'-end primer. This full-length RT-PCR product allowed RNA to be transcribed in vitro. The T7 promoter-anchored RT-PCR product was cloned and used as templates for transcription for plant inoculation test. Capped transcript RNAs transcribed from the full-length cDNA clone as well as capped transcript RNAs from the uncloned RT-PCR products were infectious and caused symptoms characteristic of KGMMV when mechanically inoculated to systemic host plants such as zucchini squash, cucumber and Nicotiana benthamiana. Transcript-derived progeny virus was indistinguishable from the wild-type virus with the same biological and biochemical properties. To our knowledge, this is the first report of the generation of a biologically active KGMMV clone, driven by the T7 promoter, that is highly infectious to cucurbitaceous plants.

N-nitrosocarbofuran, but not carbofuran, induces apoptosis and cell cycle arrest in CHL cells

Carbofuran (CF) is one of the most widely used carbamate pesticides in the world applied for insect and nematode control. Due to its widespread use in agriculture and households, contamination of food, water, and air has become serious, and consequently adverse health effects are inevitable in humans, animals, wildlife and fish. It has been reported that CF alone or in combination with other carbamate insecticides influences the level of reproductive and metabolic hormones such as thyroxine and corticosterone, and results in impairment of endocrine, immune and behavioral functions. In this study, we evaluated the effects of CF and its metabolite, the N-nitroso derivative N-nitrosocarbofuran (NOCF), on genotoxicity, cell growth, cell cycle and apoptosis of Chinese hamster lung fibroblast (CHL) cells. NOCF, but not CF, induced genotoxicity determined by Ames test. NOCF inhibited the growth of Chinese hamster lung fibroblast (CHL) cells with an IC(50) of 12.8 microM. NOCF induced apoptosis of CHL cells, which was demonstrated by morphological changes, DNA fragmentation and flow cytometric analysis. Treatment of CHL cells with NOCF induced significant G(2)/M cell cycle arrest. Caspase-3, an executioner of apoptosis was also activated by the treatment of CHL cells with NOCF. These results suggest that NOCF, that is an important metabolite of CF, leads to the induction of cell cycle arrest and apoptosis in CHL cells.

Growth and grazing rates of the heterotrophic dinoflagellate Polykrikos kofoidii on red-tide and toxic dinoflagellates

We investigated growth rates, grazing rates, and prey selection of Polykrikos kofoidii when feeding on several species of red-tide and/or toxic dinoflagellates. Polykrikos kofoidii ingested all prey species used in this study, exhibiting positive growth on Lingulodinium polyedrum, Scrippsiella trochoidea, Ceratium furca, Gymnodinium catenatum, Gyrodinium impudicum, Prorocentrum micans, and the toxic dinoflagellate Amphidinium carterae, but not on P. minimum. Specific growth rates of P. kofoidii increased rapidly with increasing density of L. polyedrum, S. trochoidea, C. furca, and G. catenatum before saturating between 500-2,000 ng C ml(-1). Specific growth rates increased continuously when P. kofoidii was fed the other prey species. Maximum specific growth rates of P. kofoidii on G. catenatum (1.12 d(-1)), S. trochoidea (0.97 d(-1)), and L. polyedrum (0.83 d(-1)) were higher than those on C. furca (0.35 d(-1)), A. carterae (0.10 d(-1)), P. micans (0.06 d(-1)), G. impudicum (0.06 d(-1)), and P. minimum (-0.03 d(-1)). Threshold prey concentrations (where net growth = 0) were 54-288 ng C ml(-1). Maximum ingestion and clearance rates of P. kofoidii on these dinoflagellates were 5-24 ng C pseudocolony(-1) d(-1) and 1.0-5.9 microl pseudocolony(-1) h(-1), respectively. Polykrikos kofoidii strongly selected L. polyedrum over S. trochoidea in prey mixtures. Polykrikos kofoidii exhibited higher maximum growth, ingestion, and clearance rates than previously reported for the mixotrophic dinoflagellate Fragilidium cf. mexicanum or the heterotrophic dinoflagellates Protoperidinium cf. divergens and P. crassipes, when grown on the same prey species. Grazing coefficients calculated by combining field data on abundances of Polykrikos spp. and co-occurring red-tide dinoflagellate prey with laboratory data on ingestion rates obtained in the present study suggest that Polykrikos spp. sometimes have a considerable grazing impact on prey populations.

Zucchini green mottle mosaic virus is a new tobamovirus; comparison of its coat protein gene with that of kyuri green mottle mosaic virus

A novel virus we call zucchini green mottle mosaic virus (ZGMMV) was isolated from zucchini squash and its properties were determined. The size and shape of its virions, and other properties suggest that the virus is a tobamovirus. The coat protein (CP) genes of ZGMMV and kyuri green mottle mosaic virus (KGMMV), which also infects zucchini squash plants, were cloned and their nucleotides sequences were determined. The CP genes of ZGMMV and KGMMV are composed of 161 amino acid residues, and they share 77.6% amino acid identity. Western blot analysis showed that the two viruses are serologically related but not identical. Comparison of the sequences with those of sixteen other tobamoviruses revealed that the two viruses had much higher identity to cucumber green mottle mosaic virus (CGMMV), another tobamovirus infectious to cucurbit plants, than other tobamoviruses. The nucleotide and amino acid sequences of ZGMMV were from 29.5 to 78.4% and from 29.3 to 77.6% identical, respectively, to those of other tobamoviruses. The predicted virion assembly origins of the two tobamoviruses were located in the CP region of the genomic RNAs, and the predicted secondary structures were more similar to that of CGMMV than those of other tobamoviruses. The seventeen tobamo-viruses could be classified into three main subgroups based on the phylogenetic tree analysis on the CP gene, and ZGMMV and KGMMV formed a third subgroup together with CGMMV and sunn-hemp mosaic virus (SHMV). These results show that ZGMMV is a previously unknown member of the Tobamovirus genus.

Modeling of the Permeate Flux during Microfiltration of BSA-Adsorbed Microspheres in a Stirred Cell

A study on the variation of the permeate flux was performed in a stirred cell charged with microspheres, to investigate the effects of the stirrer speeds (300, 400, and 600 rpm) and the BSA concentration (0.1, 0.2, 0.4, and 0.8 g/L) under constant pressure. The permeate flux increased over time before the saturation point, but it began to decrease after that point. An increase of the BSA concentration and the stirrer speed resulted in the rapid increase of the permeate flux. This is contrary to the observation of the conventional filtration experiments using a stirred cell. A resistance-in-series model was employed for the modeling of the permeate flux. The cake resistance (R(c), induced by the concentration polarization of microspheres) and the fouling resistance (R(f), induced by the adsorption of BSA inside the membrane pore) must be considered simultaneously for the modeling. These modeling results were in good agreement with the experimental data. These can be applied to the special system considering both R(c) and R(f) as well as the general filtration systems using a stirred cell. Copyright 2000 Academic Press.

Inhibition of Helicobacter pylori hemagglutination by polysaccharide fractions from roots of Panax ginseng

Polysaccharides from the roots of Panax ginseng were extracted by hot water and fractionated by using ethanol precipitation and ion exchange chromatography. Fractions FC (crude extract), F1 (fraction precipitated by ethanol), F1N (fraction unbound to DEAE-Sepharose CL-6B), and F1A (bound fraction) were obtained. Their carbohydrate analyses showed that acidic fraction F1A contains higher amounts of galactose, arabinose and uronic acids, in comparison to FC and F1. Fraction F1N mainly consists of glucose. The inhibition of Helicobacter pylori-induced hemagglutination revealed different inhibitory activities of these fractions. In particular, acidic fraction F1A showed a remarkable inhibitory activity (minimum inhibition concentration was 0.25 mg/ml) among the polysacharide fractions. However, digestion of the fraction F1A with pectinase resulted in a lower molecular weight oligosaccharide fraction F1AP which was non-inhibitory at the concentration of 4 mg/ml. Comparison of inhibitory activities and carbohydrate compositions of isolated fractions indicates that the activity correlated with the contents of galactose, arabinose, and uronic acids. These data suggest that acidic polysaccharides may be responsible for the inhibitory activity.

Effects of partial bladder outlet obstruction and its relief on types I and III collagen and detrusor contractility in the rat

Bladder outlet obstruction induces a rapid hypertrophy characterized by increased bladder mass and collagen deposition. An increase in collagen is likely to reduce the contractility and compliance of bladder wall. This study was undertaken to investigate the effects of partial bladder outlet obstruction and its relief on types I and III collagen, and the relationship between detrusor contractility and collagen types. A total of 40 female rats was used for experiment and divided into one control, one obstruction, and three recovery groups. The contractility to field stimulation was recorded; total collagen and collagen concentration were quantified. The localization of types I and III collagen and the expression of pro-alpha1(I) and alpha1(III) collagen mRNA were determined by immunohistochemical staining and Northern blot hybridization, respectively. Contractile response to field stimulation was reduced after obstruction and recovered following relief. The total amount of collagen increased after obstruction and decreased after relief; however, collagen concentration decreased after obstruction and increased following relief. Contractility correlated negatively with total collagen but positively with collagen concentration. The protein deposition of types I and III collagen was localized in lamina propria and muscle bundles in all groups. The expression of types I and III collagen gene was up regulated after obstruction, but down regulated after relief. Negative correlation between contractility and gene expressions of collagen types was significant. These data suggest that the change in localization and quantity of collagen types leads to morphologic changes of bladder and can have an impact on the contractility of detrusor. Neurourol. Urodynam. 19:29-42, 2000.

Long-term results of percutaneous endourologic management of renal infundibular stricture

PURPOSE

The long-term result of percutaneous endourologic management in the relief of infundibular stricture is not clear. We reviewed the long-term efficacy in our series of patients.

PATIENTS AND METHODS

Twenty-seven patients underwent percutaneous endourologic management between August 1990 and February 1996. This study included the 21 who could be followed for more than 2 years (mean 4.8 years). The causes of stricture were tuberculosis (N = 18; 86%) and stone (N = 3; 14%). We made a cold-knife incision in eight patients; the others underwent only dilation with fascial dilators from 20F to 30F. Success was defined as symptomatic improvement and radiographic resolution of obstruction.

RESULTS

The overall success rate was 76% (16 of 21). Seven of the eleven patients (64%) with concomitant ureteral stricture had a successful result. In the nine patients with multiple infundibular strictures, five procedure (56%) were successful. The success rates of the cold-knife or fascial dilator were 88% (7 of 8) and 69% (8 of 13), respectively. In the five patients in whom the procedure failed, ureteral stricture was associated in four and multiple infundibular strictures in four. All of them had tuberculous infundibular strictures. No significant difference in the success rate was observed according to the duration of indwelling catheter. There was no significant complication except pyelonephritis in four patients, which was controlled with conservative treatment.

CONCLUSIONS

Percutaneous endourologic management is an effective and safe procedure to treat renal infundibular stricture. Risk factors for failure are multiple infundibular strictures and concomitant ureteral stricture. If the procedure does fail, other treatments have not been compromised. Cold-knife incision seems to be more effective than dilation.

Continuous separation of serum proteins using a stirred cell charged with carboxylated and sulfonated microspheres

We contrived a new separation system using a stirred cell charged with uncoupled microsphere similar to the chromatographic separation. Microspheres, carboxylated PS/PMAA and sulfonated PS/PNaSS, were prepared by emulsifier-free emulsion polymerization. To complement the submicron size weakness and the absence of ligands, we employed the latex form, the dispersion of microsphere, and took advantage of interaction relationships between proteins and microspheres. Adsorption isotherm is contemplated to investigate continuous separation behaviours of serum proteins. Selectivity of separation is in the following order: PS/PNaSS-2.0 (high sulfonated) < PS/PNaSS-0.3 (low sulfonated) < PS/PMAA-0.5 (low carboxylated). Unlike previous works on batch separation, not only the adsorbed amount in equilibrium (Cm), but also adsorption coefficient (K), played an important role in continuous separation. Functional groups (carboxyl and sulfonate), induced from the co-monomer, also affected the adsorption behaviours.

Collagen studies for pediatric ureteropelvic junction obstruction

OBJECTIVES

Ureteropelvic junction (UPJ) obstruction is the most common form of urinary tract obstruction in pediatrics. There is controversy regarding the need for early surgical intervention in many patients with apparent neonatal UPJ obstruction. To demonstrate the differences in type and amount of collagen in adult and pediatric UPJ obstruction, collagen studies were performed.

METHODS

The experimental groups are 9 pediatric patients with UPJ obstruction and 13 adult patients with UPJ obstruction. Six patients with normal UPJ were assigned as controls for each experimental group. The collagen content of UPJ was quantitated by hydroxyproline analysis. Immunohistochemical staining and Western blotting for collagen types I and III were performed.

RESULTS

The collagen content of pediatric UPJ was significantly lower in value than that of adult UPJ (P < 0.05). Immunohistochemical staining revealed that collagen type I was located in interfascicular space and collagen type III was located in intrafascicular space in both age groups. In Western blotting the relative intensity of collagen type III for pediatric UPJ was weaker than that of adult groups.

CONCLUSIONS

These results suggest that a larger series of patients should be examined to determine whether quantitative analysis for collagen types I and III would provide some kind of prognostic test for UPJ outcome in pediatric patients.

Percutaneous endoscopic management of upper ureteral stricture size of stent

PURPOSE

We determined the optimal size (6F versus 14/7F) of stent after endoscopic surgery based on clinical data.

MATERIALS AND METHODS

Between 1989 and 1993 we performed percutaneous endopyelotomy and endoureterotomy in 40 cases of ureteropelvic junction or upper ureteral strictures. The causes of stricture were primary in 20 cases, tuberculosis in 9, previous operation in 6 and others in 5. After endoscopic management we placed 6F internal stents in 25 patients (13 in primary and 12 in secondary cases) or 14/7F endopyelotomy stents in 15 patients (7 in primary and 8 in secondary cases) for 6 to 8 weeks (average 54.2 days). Coexisting stones or infundibular strictures were managed simultaneously. All patients have been followed for a minimum of 7 months postoperatively (range 7 to 55, average 38).

RESULTS

Overall success rate was 84% (92.3 in primary and 75% in secondary cases) with the 6F stent and 93.3% (85.7% in primary and 100% in secondary cases) with the 14/7F endopyelotomy stent.

CONCLUSIONS

The small number of patients in each group did not reach statistical significance. However, there was a definite trend for better results with the use of 14/7F stents in patients with secondary stricture (100% versus 75%), although the difference in success rates between 6F and 14/7F stents was not significant statistically (p = 0.13).

Cochlear fistula in chronic otitis media with cholesteatoma

Labyrinthine fistula in chronic otitis media with cholesteatoma most commonly involves the horizontal semicircular canal. We report three cases of cochlear fistula in chronic otitis media with cholesteatoma. All of them had a long history of otorrhea. One patient had total hearing loss of the affected side. The other two patients had conductive hearing loss. Radical mastoidectomy had been done in all cases. Cholesteatoma in the tympanic cavity destroyed the basal turn of the cochlea. These fistulas were sealed with muscle or Gelfoam with streptomycin. We found no fistula in the semicircular canal in any of the three cases. We report three cases of cochlear fistula in chronic otitis media with cholesteatoma, and review the literature.

Expression of antisense PC1 in stably transfected RIN5F cells significantly reduces CCK 8 biosynthesis

The subtilisin-like endoprotease PC1 (PC3) has been implicated in the processing of a number of prohormones. To evaluate whether PC1 may be important for the processing of pro CCK to CCK 8, stable cell lines expressing a portion of the PC1 cDNA in the antisense orientation were established from RIN5F cells. These cells express CCK mRNA, produce and display regulated secretion of CCK 8. One of the clones, R1E8, expresses antisense PC1 mRNA as determined by reverse transcriptase-PCR (RT-PCR) and contains a significantly reduced level of PC1 protein. As compared to both RIN5F and RIN5F control cells (transfected with the expression plasmid containing no antisense message), R1E8 contains only about 30% cell content of CCK 8. These results suggest that PC1 may be important for the processing of CCK 8 from pro CCK.

Developmental factors in the contractile response of rabbit urinary bladder: effect of anoxia and extracellular acidosis

Previous studies have demonstrated that the mechanism of excitation contraction coupling changes with normal development in rabbit urinary bladder smooth muscle. The present study was designed to determine whether there were any differences in the effects of anoxia and extracellular acidosis in response to field stimulation, bethanechol and KCl between mature (8 weeks) and neonatal (3 days) rabbit bladder smooth muscle. Bladder smooth muscle strips from mature and neonatal New Zealand White rabbits were mounted in organ baths and bathed in oxygenated Tyrode's solution. Anoxia was produced by changing the gas mixture to 95% nitrogen/5% CO2 and the effects on contractility were determined at different times after initiation of anoxia. The extracellular acidosis was produced by decreasing the buffer's NaHCO3 concentration. We conclude that bladder smooth muscle does not exhibit an age-specific ability to counteract the effects of anoxia or acidosis as is seen in the developing rabbit myocardium. Instead it appears that the purinergic mechanisms of contraction are much more sensitive to the effects of anoxia or acidosis. Neonatal bladder smooth muscle exhibits a greater drop in contractility with anoxia or acidosis at low frequency (2 Hz) field stimulation; we attribute this to the fact that neonatal bladder smooth muscle has a greater purinergic component in its response to field stimulation. These differences in the responses to anoxia and pH reflect alternate mechanisms of pharmacologic activation, and not inherent differences in the biochemistry of the maturing smooth muscle.

Effect of partial outlet obstruction on the biphasic response to field stimulation at different concentrations of calcium

The contractile response of the rabbit urinary bladder smooth muscle to field stimulation is biphasic in nature consisting of an initial phasic contraction followed by a prolonged tonic contraction. The phasic contraction is mediated by a rapid rise in intracellular free calcium concentration which in turn is achieved by a combination of the entry of extracellular calcium into the cell and by the mobilization and release of calcium from intracellular storage sites. Partial bladder outlet obstruction in rabbits is associated with a marked depression of contractile function. The current experiments were designed to: (1) investigate the role of extracellular calcium in mediating the phasic and tonic components of the contractile response to field stimulation and (2) determine the effect of partial outlet obstruction on this relationship. The results can be summarized as follows: in the control bladder, increasing the extracellular calcium concentration from 0.6 to 5.4 mmol/l enhanced the phasic contractile response to a 2-Hz stimulation to a significantly greater degree than the response to a 16-Hz stimulation. Increasing the extracellular calcium concentration had no effect on the plateau phase of the contractile response. Partial outlet obstruction significantly reduced the phasic and tonic responses to all frequencies of stimulation. In general, there was a greater reduction in the tonic response to field stimulation (relative to the phasic response).

Effect of partial outlet obstruction of the rabbit urinary bladder on ryanodine binding to microsomal membranes

1. Partial outlet of obstruction of the rabbit urinary bladder results in a significant increase in the ability of ryanodine to inhibit field stimulated contraction. The current study determined the effect of outlet obstruction on ryanodine binding to microsomal membranes. 2. The results demonstrate: (i) Ryanodine binding is linear showing one set of ryanodine binding sites (Bmax = 28 +/- 3.5 fmol/mg protein; Kd = 4.2 nM). (ii) Total ryanodine binding was slightly increased at 1 and 3 day following obstruction. (iii) Binding increased approx 4-fold at 5 and 7 days post obstruction. (iv) No change in the Kds were noted at any time period. 3. The results of these studies indicate that smooth muscle hypertrophy secondary to partial outlet obstruction induces a marked increase in the role of intracellular calcium in the mediation of the contractile response to field stimulation.

Effect of ryanodine on the contractile response of the normal and hypertrophied rabbit urinary bladder to field stimulation

Bladder contraction, similar to most smooth muscle contraction, is dependent on both the translocation of extracellular calcium across the cell membrane, and the calcium-stimulated release of intracellular bound calcium. Partial outlet obstruction of the urinary bladder induces a marked increase in bladder mass which results in part from a substantial hypertrophy of the smooth muscle elements. In addition, the increase in bladder mass is associated with specific contractile dysfunctions. It is not known if the contractile dysfunction induced by partial outlet obstruction is related to alterations in calcium metabolism. Ryanodine is a pharmacological tool which can be utilized to study the role of intracellular calcium in mediating contractile events. Ryanodine stimulates the loss of intracellular calcium (bound in the sarcoplasmic reticulum) and reduces the participation of intracellular calcium in the contractile response to specific forms of stimulation. The current study investigates the effect of partial outlet obstruction on the ryanodine inhibition of the contractile response of rabbit urinary bladder to field stimulation. New Zealand White rabbits were anesthetized and catheterized with an 8-french Foley catheter. A 00 silk suture was surgically placed around the catheterized urethra, the incision closed, and the catheter removed. After 1, 3, 5 and 7 days of partial outlet obstruction, the bladder was rapidly removed and utilized immediately for contractile studies. The effect of ryanodine (0-80 microM) on the peak response to 2-, 8- and 16-Hz field stimulation at 0.6, 1.8 and 5.4 mM calcium was determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Yeast artificial chromosome-based genome mapping: some lessons from Xq24-q28

Yeast artificial chromosomes (YACs) have recently provided a potential route to long-range coverage of complex genomes in contiguous cloned DNA. In a pilot project for 50 Mb (1.5% of the human genome), a variety of techniques have been applied to assemble Xq24-q28 YAC contigs up to 8 Mb in length and assess their quality. The results indicate the relative strength of several approaches and support the adequacy of YAC-based methods for mapping the human genome.

Lichen planus specific antigen and antibodies--in a patient with generalized lichen planus

A 43-year-old man with generalized lichen planus demonstrated serum antibodies against autologous lesional skin. Indirect immunofluorescence using serum and papular lesional skin revealed a lichen planus specific antigen found only in the granular layer. The specific tissue antigen was not detected in normal skin from this patient, in normal skin from patients with skin disorders other than lichen planus or in skin from normal control persons. When titers of the serum antibodies against lichen planus antigen were examined before and after a successful therapy a positive correlation of the titer could be found in this patient.