Sire pedigree error estimation and sire verification of the Taiwan dairy cattle population by using SNP markers

Information regarding the correct pedigree of and relationship between animals is useful for managing dairy breeding, reducing inbreeding, estimating breeding value, and establishing correct breeding programs. Additionally, the successful implementation of progeny testing is crucial for improving the genetics of dairy cattle, which depends on the availability of correct pedigree information. Incorrect pedigree information leads to bias in bull evaluation. In this study, Neogen GeneSeek Genomic Profiler (GGP) 50K SNP chips were used to identify and verify the sire of Taiwanese Holstein dairy cattle and analyze the reasons that lead to incorrect sire records. Samples were collected from 2,059 cows of 36 dairy farms, and the pedigree information was provided by breeders. The results of sire verification can be divided into three categories: submitted unconfirmed sire, submitted confirmed sire, and incorrectly submitted verified sire. Data on the sires of 1,323 (64.25%) and 572 (27.78%) dairy cows were verified and discovered, respectively. Sires of 1,895 (92.03%) dairy cattle were identified, which showed that the paternal pedigree of dairy cattle could be discovered and verified through genetic testing. An error-like analysis revealed that the data of 37 sires were incorrectly recorded because the bull's NAAB code number was incorrectly entered into the insemination records: for 19 sires, the wrong bull was recorded because the frozen semen of a bull placed in the wrong storage tank was used, 6 had no sire records, and for 12 sires, the NAAB code of the correct bull was recorded but with a wrong stud code, marketing code, or unique number for the stud or breed. To reduce recorded sire error rates by at least 27.78%, automated identification of the mated bull must be adopted to reduce human error and improve dairy breeding management on dairy farms.

Anti-GABAB receptor encephalitis associated with combined small cell lung carcinoma

Autoimmune encephalitis with antibodies against the gamma-aminobutyric acid-B receptor is a relatively rare disease. We report a case with characteristic symptoms of limbic encephalitis associated with combined small cell lung carcinoma. The brain magnetic resonance imaging showed bilateral temporal lesions and the photoemission tomography revealed regional heterogenous metabolism across the brain. The double labeling of anti-gamma-aminobutyric acid-B receptor autoantibodies both in the tissues of neuroendocrine and small cell neoplasia was a unique feature of this patient.

Case Report: Plasma Biomarkers Reflect Immune Mechanisms of Guillain-Barré Syndrome

This case series reported a group of patients with Guillain–Barré syndrome (GBS) and their plasma cytokine changes before and after immunotherapy. We aimed to understand GBS's pathogenesis and pathophysiology through observing the interval differences of the representative cytokines, which were the thymus and activation regulated chemokine (TARC) for T-cell chemotaxis, CD40 ligand (CD40L) for cosimulation of B and T cells, activated complement component C5/C5a, and brain-derived neurotrophic factor (BDNF) for survival and regenerative responses to nerve injuries. The fluorescence magnetic bead-based multiplexing immunoassay simultaneously quantified the five cytokines in a single sample. From June 2018 to December 2019, we enrolled five GBS patients who had completed before–after blood cytokine measurements. One patient was diagnosed with paraneoplastic GBS and excluded from the following cytokine analysis. The BDNF level decreased consistently in all the patients and made it a potential biomarker for the acute stage of GBS. Interval changes of the other four cytokines were relatively inconsistent and possibly related to interindividual differences in the immune response to GBS triggers, types of GBS variants, and classes of antiganglioside antibodies. In summary, utilizing the multiplexing immunoassay helps in understanding the complex immune mechanisms of GBS and the variation of immune responses in GBS subtypes; this method is feasible for identifying potential biomarkers of GBS.

Association between estimated glomerular filtration rate and clinical outcomes in ischemic stroke patients with high-grade carotid artery stenosis

Background

Chronic kidney disease has been identified as a risk factor affecting stroke prognosis. High-grade carotid artery stenosis (CAS) is associated with distal hemodynamic compromise. The association between the estimated glomerular filtration rate (eGFR) and ischemic stroke (IS) outcome in patients with high-grade CAS remains unclear. We aimed to investigate the association between eGFR and outcomes of acute IS patients with high-grade CAS.

Methods

From January 1, 2007 to April 30, 2012, we enrolled 372 acute IS patients with high-grade CAS and prospectively observed them for 5 years. The eGFR on admission was assessed using the Modification of Diet in Renal Disease Study equation. Demographic features, vascular risk factors, comorbidities, and outcomes were compared between different eGFR levels.

Results

Among 372 individuals, 76 (20.4%) had an eGFR < 45, 65 (17.5%) had an eGFR between 45 and 59, and 231 (62.1%) had an eGFR ≥60 mL/min/1.73 m². Compared to other groups, in the eGFR < 45 mL/min/1.73 m² group, the prevalence rates of hypertension, diabetes mellitus, coronary artery disease, congestive heart failure, valvular heart disease, and gout were significantly higher (P = 0.013, P = 0.030, P = 0.001, P < 0.001, P = 0.043, and P < 0.001, respectively). Patients with eGFR < 45 mL/min/1.73 m² demonstrated lower hemoglobin and total cholesterol levels compared with other groups (P < 0.001 and P = 0.048). The blood potassium and uric acid levels were significantly higher in patients with eGFR < 45 mL/min/1.73 m² (P < 0.001 and P < 0.001). The multivariate Cox proportional hazards model indicated that eGFR < 45 mL/min/1.73 m² was a significant risk factor for 5-year all-cause mortality in IS patients with high-grade CAS after adjusting for these variables (hazard ratio = 2.05; 95% CI = 1.31–3.21; P = 0.002).

Conclusions

eGFR < 45 mL/min/1.73 m² was associated with an increased risk of 5-year all-cause mortality in acute IS patients with high-grade CAS. Whether aggressive treatment of chronic kidney disease in IS patients with high-grade CAS can improve stroke outcomes should be confirmed in future studies.

Asian Foxtail (Uraria crinita), a New Host for Sclerotium rolfsii from Taiwan

Asian foxtail (Uraria crinita (L.) Desv. ex DC.) is an herb cultivated for the use of roots and stems in Taiwanese cuisine. In September 2013, symptoms of leaf blight and basal rot were observed on U. crinita in a commercial field in Longjing District, Taichung, Taiwan, at an incidence of approximately 20%. White mycelia and brown sclerotia formed on the surfaces of the basal stems. The infected plant gradually wilted and eventually died. Diseased lower stem tissues were surface sterilized in 0.6% NaOCl, rinsed with sterile distilled water, and transferred to potato dextrose agar plates. The cultures were incubated at 25°C in the dark. The radial mycelial growth was 9.0 mm/day during the first 4 days, and the diameter of mature sclerotia was 1.76 mm following 3 weeks of incubation. The internal transcribed spacer (ITS) sequence of the isolate was amplified by PCR using the primers ITS5 and ITS4 (2). The amplicon was cloned, sequenced, and deposited in GenBank (Accession No. KJ677121). The sequence similarity was 99% compared with that of Sclerotium rolfsii Sacc. from Spain (GU080230) (1). Based on the characteristics, the fungus was identified as S. rolfsii. The fungal isolate (BCRC FU30230) was deposited in the Bioresource Collection and Research Center, Hsinchu, Taiwan. Pathogenicity tests were conducted on six 2-month-old potted U. crinita plants in a greenhouse. Prior to infesting the plant, fungal inoculum of S. rolfsii BCRC FU30230 was prepared by inoculating the isolate on autoclaved rice (rice/water/dextrose = 50:50:1) in a flask. After 20 days incubation at room temperature, rice colonized by S. rolfsii was placed near the base of the plants (approximately 30 g/plant) in the greenhouse. Sterile rice applied to an equal number of plants served as negative controls. All inoculated plants developed blight symptoms with mycelia and sclerotia produced near the bases of each seedling 1 week after inoculation at an average temperature of 26°C. The control plants remained healthy. The pathogen re-isolated from the inoculated plants was morphologically identical to the original isolate. The pathogenicity test was repeated by inoculated healthy plants with reduced inoculum (five granules/plant). A delay of symptom development was observed and similar results were obtained. To our knowledge, this is the first report of Sclerotium rot on U. crinita in Taiwan, and the first report on U. crinita as a host for S. rolfsii. References: (1) E. Remesal et al. Plant Dis. 94:280, 2010. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

First Report of Bacterial Spot Caused by Xanthomonas arboricola pv. pruni on Japanese Plum in Taiwan

Prunus salicina Lindl., also known as Japanese plum, is a temperate-zone fruit tree grown in mountainous areas of Taiwan. The planted area in Taiwan is approximately 3,000 ha. In June 2011, more than 20% of plum fruits harvested in an orchard in Lishan (elevation about 2,000 m) showed black, mostly circular, sunken necrotic lesions. Leaves with a shot-hole appearance and cankered branches were found when investigating the orchard. Bacteria were isolated from symptomatic fruits, leaves, and branches. Isolation on nutrient agar detected colonies that were yellow, mucoid, gram-negative, Xanthomonas-like, and induced hypersensitive responses on tomatoes. Three voucher isolates, BCRC80476, BCRC80478, and BCRC80481, obtained from the fruit, leaf, and branch, respectively, were deposited in the Bioresource Collection and Research Center, Hsinchu, Taiwan. Molecular analyses were conducted for species identification. Sequences of the gyrB gene of the three voucher isolates (GenBank Accession Nos. KC202288, KC202289, and KC202287) were 100% identical to that of Xanthomonas arboricola pv. pruni pathotype strain ICMP51 (2). In addition, DNA fragments of the xopE3 gene (an X. arboricola pv. pruni specific T3E gene, approximately 381 bp) were PCR amplified using the primer pair fw-5'CCGACATTGCCGTCAGCGATCACG3' and rv-5'AGCGTTCTTGGGTGTGTTGAGCATTTG3' (1). The bacterial isolates were identified as X. arboricola pv. pruni on the basis of the colony characteristics, sequence homology, and the specific PCR assay. Pathogenicity was confirmed by inoculation of greenhouse-potted P. salicina plants with strains BCRC80476, BCRC80478, and BCRC80481 using bacterial suspensions (6.7 × 10⁸ CFU per ml) in 0.01% Tween 20. Five plants were evenly sprayed with inoculum of each bacterial isolate and covered with plastic bags for 3 days. One week post inoculation, at an average temperature of 19°C, the 15 inoculated plants produced brown-purple spots delimited by a chlorotic margin on the leaves. Three weeks post inoculation, the necrotic leaf spots completely deteriorated, leaving a shot-hole appearance, and the branches showed lesions similar to those observed in the fields. The pathogen was reisolated from the symptomatic tissues, fulfilling Koch's postulates. Control plants sprayed with 0.01% Tween 20 remained symptomless. To our knowledge, this is the first record of X. arboricola pv. pruni causing bacterial spot on P. salicina in Taiwan. References: (1) A. Hajri et al. Appl. Environ. Microbiol. 78:371, 2012. (2) J. M. Young et al. Syst. Appl. Microbiol. 31:366, 2008.

First Report of Stem and Leaf Blight Caused by Sclerotinia sclerotiorum on Eustoma in Taiwan

Eustoma (Eustoma russellianum) is an economically important cut flower in Taiwan. Each year more than 1.7 million dozen flowers, mainly exported to Japan in the winter, are produced in greenhouses. In January 2011, eustoma plants with stem and leaf blight symptoms were observed in some greenhouses in Changhua County, Taiwan, at an incidence of 2%. Brown and rotten lesions were presented on the stem and nearby leaves, with white mycelia growing on the surface and black sclerotia (up to 7 mm long) produced inside the stem. Infected plants were completely blighted and eventually died. Diseased stem tissues collected from the field were surface sterilized for 3 min in 0.6% NaOCl, rinsed with sterilized distilled water, and plated on potato dextrose agar. White fungal colonies were consistently isolated. The cultures produced large sclerotia at the peripheries of the plates. Internal transcribed spacer (ITS) sequences of two voucher isolates were determined and deposited in GenBank (Accession Nos. JQ653934 and JQ653935). The sequences were 100% identical to that of Sclerotinia sclerotiorum strain ATCC MYA-4521 (Accession No. FJ810516). In addition, PCR amplified DNA fragments (approximately 630 bp) were obtained by the S. sclerotiorum specific primer pair MP_SsF and MP_UniR (1). On the basis of morphology, ITS sequence homology, and the specific PCR detection, the fungus was identified as S. sclerotiorum. The two fungal isolates (BCRC34830 and BCRC34831) were deposited in Bioresource Collection and Research Center, Hsinchu, Taiwan. Pathogenicity tests were conducted on 1-month-old, second flush eustoma cultivars Ex Rosa Pink Flash and Rosina Blue Ver. 2 after primary flowers had been harvested in the greenhouse. Fungal inoculum consisting of Tref horticultural substrate and wet sterilized rice colonized by S. sclerotiorum BCRC34830 (substrate-rice-water ratio of 2:1:1) was placed near the base of the plants. Ten plants of each cultivar were inoculated with about 800 g of the mixture. Sterile mixture applied to an equal number of plants served as negative controls. Eight plants of each cultivar showed blight symptoms after 1 month of incubation at an average temperature of 26°C. All control plants remained healthy. The pathogen reisolated from the inoculated stems produced sclerotia identical to those isolated in the field, fulfilling Koch's postulates. The pathogenicity test was repeated with similar results. S. sclerotiorum has been reported on eustoma in Argentina (2). To our knowledge, this is the first report of Sclerotinia blight on eustoma in Taiwan. Although the disease was not prevalent on eustoma, the inoculum could be dormant in the greenhouse soil. Awareness of the potential perennial problem could increase the quality of the flowers exported and benefit the flower industry. References: (1) S. Hirschhäuser and J. Fröhlich. Int. J. Food Microbiol. 118:151, 2007. (2) S. Wolcan et al. Plant Dis. 80:223, 1996.

First Report of Phytophthora drechsleri Associated with Stem and Foliar Blight of Gynura bicolor in Taiwan

Gynura bicolor (Roxb. ex Willd.) DC., known as Okinawa spinach or hong-feng-cai, is a commonly consumed vegetable in Asian countries. In May 2010, plants with blight and wilt symptoms were observed in commercial vegetable farms in Changhua, Taiwan. Light brown-to-black blight lesions developed from the top of the stems to the petioles and extended to the base of the leaves. Severely infected plants declined and eventually died. Disease incidence was approximately 20%. Samples of symptomatic tissues were surface sterilized in 0.6% NaOCl and plated on water agar. A Phytophthora sp. was consistently isolated and further plated on 10% unclarified V8 juice agar, with daily radial growths of 7.6, 8.6, 5.7, and 2.4 mm at 25, 30, 35, and 37°C, respectively. Four replicates were measured for each temperature. No hyphal growth was observed at 39°C. Intercalary hyphal swellings and proliferating sporangia were produced in culture plates flooded with sterile distilled water. Sporangia were nonpapillate, obpyriform to ellipsoid, base tapered or rounded, and 43.3 (27.5 to 59.3) × 27.6 (18.5 to 36.3) μm. Clamydospores and oospores were not observed. Oospores were present in dual cultures with an isolate of P. nicotianae (p731) (1) A2 mating type, indicating that the isolate was heterothallic. A portion of the internal transcribed spacer sequence was deposited in GenBank (Accession No. HQ717146). The sequence was 99% identical to that of P. drechsleri SCRP232 (ATCC46724) (3), a type isolate of the species. The pathogen was identified as P. drechsleri Tucker based on temperature growth, morphological characteristics, and ITS sequence homology (3). To evaluate pathogenicity, the isolated P. drechsleri was inoculated on greenhouse-potted G. bicolor plants. Inoculum was obtained by grinding two dishes of the pathogen cultured on potato dextrose agar (PDA) with sterile distilled water in a blender. After filtering through a gauze layer, the filtrate was aliquoted to 240 ml. The inoculum (approximately 180 sporangia/ml) was sprayed on 24 plants of G. bicolor. An equal number of plants treated with sterile PDA processed in the same way served as controls. After 1 week, incubation at an average temperature of 29°C, blight and wilt symptoms similar to those observed in the fields appeared on 12 inoculated plants. The pathogen was reisolated from the lesions of diseased stems and leaves, fulfilling Koch's postulates. The controls remained symptomless. The pathogenicity test was repeated once with similar results. G. bicolor in Taiwan has been recorded to be infected by P. cryptogea (1,2), a species that resembles P. drechsleri. The recorded isolates of P. cryptogea did not have a maximal growth temperature at or above 35°C (1,2), a distinctive characteristic to discriminate between the two species (3). To our knowledge, this is the first report of P. drechsleri being associated with stem and foliar blight of G. bicolor. References: (1) P. J. Ann. Plant Pathol. Bull. 5:146, 1996. (2) H. H. Ho et al. The Genus Phytophthora in Taiwan. Institute of Botany, Academia Sinica, Taipei, 1995. (3) R. Mostowfizadeh-Ghalamfarsa et al. Fungal Biol. 114:325, 2010.

First Report of Neofusicoccum parvum Associated with Stem Canker and Dieback of Asian Pear Trees in Taiwan

Asian pear tree (Pyrus pyrifolia) is an important fruit crop in Asian countries. Between the autumn of 2008 and the summer of 2009, stem cankers and twig diebacks of Asian pear trees were observed in middle Taiwan. Necrotic lesions extending from branch scars progressed with age, resulting in darkened vascular discoloration. Two cultivars of Asian pear, Taichung No. 2 grown in Changhwa County and Heng-shan grown in Taichung County, showed the same symptoms. Disease incidence increased rapidly after a rain or storm event, eventually exceeding 50%. Pycnidia on severely infected branches contained one-celled, fusiform to ellipsoidal, smooth- and thin-walled hyaline conidia, with an average length (L) and width (W) of 19.1 (11.3 to 24.8) × 5.9 (4.5 to 8.0) μm and a L/W ratio of 3.2 (n = 44). Diseased branch tissues collected from the two locations were surface sterilized in 0.6% NaOCl, rinsed with water, and plated on potato dextrose agar (PDA). Fungal isolates, recovered from both locations, produced white, aerial mycelium and became dull gray within a week after incubating plates at 25°C. To confirm the identities of the isolates, the internal transcribed spacer (ITS) regions amplified with primers ITS1/ITS4 were deposited in GenBank (Accession Nos. GU395186 and GU395187). Both of the sequences were 99% identical to that of Neofusicoccum parvum (Accession No. EU882162) over a 534-bp alignment. Thus, both morphological and molecular characters confirmed this species as N. parvum (3), reported as the anamorph of Botryosphaeria parva (1). The two voucher isolates (BCRC34605 and BCRC34609) were deposited in Bioresource Collection and Research Center, Hsinchu, Taiwan. Pathogenicity tests were first conducted on 2-year-old greenhouse-potted Asian pear trees utilizing N. parvum isolate BCRC34605. Ten plants of the cv. Mi-li were stem wounded with a 5-mm cork borer at a depth of 2 mm. Inoculation consisted of inserting 5-mm mycelium plugs of the pathogen into the wounds and wrapping with Parafilm. Sterile PDA plugs applied to an equal number of plants with the same methods served as the controls. After 2 months incubation at an average temperature of 21°C, all inoculated plants exhibited necrotic lesions with a mean length of 23.5 mm and the control plants remained symptomless. The pathogen was reisolated from lesions of inoculated stems, thus fulfilling Koch's postulates. Pathogenicity tests were repeated by inoculating the other N. parvum isolate (BCRC34609) on pear cv. Taichung No. 2, resulting in similar results. N. parvum has been reported causing dieback and canker in a wide range of fruit trees, including grapevine (4) and mango trees (2). To our knowledge, this is the first report of N. parvum associated with stem canker and dieback on Asian pear trees. In addition, this is a newly recorded species for the mycobiota of Taiwan. References: (1) P. W. Crous et al. Stud. Mycol. 55:235, 2006. (2) J. Javier-Alva et al. Plant Dis. 93:426, 2009. (3) S. R. Mohali et al. Fungal Divers. 25:103, 2007. (4) J. R. Urbez-Torres and W. D. Gubler. Plant Dis. 93:584, 2009.

Complexity of cis-regulatory organization of six3a during forebrain and eye development in zebrafish

BACKGROUND

Six3a belongs to the SIX family of homeodomain proteins and is expressed in the most anterior neural plate at the beginning of neurogenesis in various species. Though the function of Six3a as a crucial regulator of eye and forebrain development has been thoroughly investigated, the transcriptional regulation of six3a is not well understood.

RESULTS

To elucidate the transcriptional regulation of six3a, we performed an in vivo reporter assay. Alignment of the 21-kb region surrounding the zebrafish six3a gene with the analogous region from different species identified several conserved non-coding modules. Transgenesis in zebrafish identified two enhancer elements and one suppressor. The D module drives the GFP reporter in the forebrain and eyes at an early stage, while the A module is responsible for the later expression. The A module also works as a repressor suppressing ectopic expression from the D module. Mutational analysis further minimized the A module to four highly conserved elements and the D module to three elements. Using electrophoresis mobility shift assays, we also provided evidence for the presence of DNA-binding proteins in embryonic nuclear extracts. The transcription factors that may occupy those highly conserved elements were also predicted.

CONCLUSION

This study provides a comprehensive view of six3a transcription regulation during brain and eye development and offers an opportunity to establish the gene regulatory networks underlying neurogenesis in zebrafish.

First Report of Anthracnose Caused by Colletotrichum acutatum on Mung Bean Sprouts in Taiwan

Mung bean sprouts (Vigna radiata (L.) R. Wilczek) are a commonly consumed vegetable in Asian countries. Anthracnose lesions on mung bean sprouts (cv. You-lu-dou from Mayamar) were found in an indoor sprouting facility in Taichung County, Taiwan in May of 2009. The incidence of disease exceeded 90% in some lots. Infected hypocotyls had smooth, diamond-shaped to fusiform brown spots, which became further depressed and enlarged with age. A fungus was isolated on potato dextrose agar (PDA) from symptomatic hypocotyls after surface sterilization in 0.6% NaOCl. Fungal colonies were initially salmon to orange in color and became greenish gray on the surface within a week. Setae were not produced in acervuli that developed on PDA. Conidia in the acervuli were one-celled, cylindrical, and hyaline with an average length and width of 14.8 (7.0 to 23.7) × 4.9 (3.3 to 6.7) μm (n = 53). The internal transcribed spacer (ITS) region was amplified with primers ITS1 and ITS4 (4). The sequence was deposited in GenBank (Accession No. GQ889269). The sequence was 99% identical to that of ATCC 56816 strain of Glomerella acutata (Guerber & J. C. Correll), the teleomorph of Colletotrichum acutatum (J. H. Simmonds) over a 522-bp alignment. Thus, the mung bean pathogen was identified as C. acutatum based on morphological (1) and molecular characters. Pathogenicity of the strain was determined by inoculating mung bean seeds from I-Mei Foods Co. (imported from Australia). The seeds were disinfested in 0.6% NaOCl for 10 min, rinsed with sterile distilled water twice, and immersed in a conidial suspension (1.5 × 10⁴ conidia/ml) of C. acutatum for 10 min. Fifteen inoculated seeds were placed on moistened paper towels, distributed into three flasks, and stored in the dark at 32°C. Symptoms similar to those observed on the original sprouts appeared 3 days later on the hypocotyls of the seedlings and all seedlings were infected by day five. Conidia of C. acutatum were produced on all lesions and colonies of C. acutatum were recovered from symptomatic tissues, fulfilling Koch's postulates. Controls (seed immersed in water) remained symptomless. The pathogenicity test was repeated with similar results. The pathogen has been recorded on mung bean sprouts in Korea (2) and on other Vigna spp. in India (3). To our knowledge, this is the first report of sprout rot of mung bean caused by C. acutatum in Taiwan. References: (1) B. J. Dyko and J. E. M. Mordue. No. 630 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1979. (2) D. K. Kim et al. Plant Pathol. J. 19:203, 2003. (3) K. P. R. Prasanna. Seed Sci. Technol. 13:821, 1985. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, New York, 1990.

White-light electroluminescence from ZnO nanorods/polyfluorene by solution-based growth

We report bright white-light electroluminescence (EL) from a diode structure consisting of a ZnO nanorod (NR) and a p-type conducting polymer of poly(fluorine) (PF) fabricated using a hydrothermal method. ZnO NRs are successfully grown on an organic layer of PF using a modified seeding layer. The EL spectrum shows a broad emission band covering the entire visible range from 400 to 800 nm. White-light emission is possible because the ZnO-defect-related emission from the ZnO NR/PF heterostructure is enhanced to become over thousand times stronger than that from the usual ZnO NR structure. This strong green-yellow emission associated with the ZnO defects, combined with the blue PF-related emission, results in the white-light emission. Enhancement of the ZnO-defect emission is caused by the presence of Zn(OH)(2) at the interface between the ZnO NRs and PF. Fourier transform infrared spectroscopy reveals that the absorption peaks at 3441, 3502, and 3574 cm(-1) corresponding to the OH group are formed at the ZnO NR/PF heterostructure, which confirms the enhancement of defect emission from the ZnO NR/PF heterostructure. The processing procedure revealed in this work is a convenient and low-cost way to fabricate ZnO-based white-light-emitting devices.

Simulation of water molecules inside gold nanotubes of various sizes and temperatures

This study investigates the behavior of water molecules inside Au nanotubes by molecular dynamics. Different sizes of Au nanotubes under three temperatures for three levels of density of Au nanotube have been studied. The structure of each thermodynamic state is analyzed through the characterization of the hydrogen-bond network. An observation of the water molecule distribution reveals that the adsorption of water molecules creates shell-like formation of water near the Au nanotube wall, and such formations are found to be more pronounced within an Au nanotube. Au atoms of different sizes have an affinity for water molecules at different temperatures.

Developmental gene regulatory networks in the zebrafish embryo

The genomic developmental program operates mainly through the regulated expression of genes encoding transcription factors and signaling pathways. Complex networks of regulatory genetic interactions control developmental cell specification and fates. Development in the zebrafish, Danio rerio, has been studied extensively and large amounts of experimental data, including information on spatial and temporal gene expression patterns, are available. A wide variety of maternal and zygotic regulatory factors and signaling pathways have been discovered in zebrafish, and these provide a useful starting point for reconstructing the gene regulatory networks (GRNs) underlying development. In this review, we describe in detail the genetic regulatory subcircuits responsible for dorsoanterior-ventroposterior patterning and endoderm formation. We describe a number of regulatory motifs, which appear to act as the functional building blocks of the GRNs. Different positive feedback loops drive the ventral and dorsal specification processes. Mutual exclusivity in dorsal-ventral polarity in zebrafish is governed by intra-cellular cross-inhibiting GRN motifs, including vent/dharma and tll1/chordin. The dorsal-ventral axis seems to be determined by competition between two maternally driven positive-feedback loops (one operating on Dharma, the other on Bmp). This is the first systematic approach aimed at developing an integrated model of the GRNs underlying zebrafish development. Comparison of GRNs' organizational motifs between different species will provide insights into developmental specification and its evolution. The online version of the zebrafish GRNs can be found at http://www.zebrafishGRNs.org.

Transcranial near-infrared light therapy improves motor function following embolic strokes in rabbits: an extended therapeutic window study using continuous and pulse frequency delivery modes

Photon or near-infrared light therapy (NILT) may be an effective neuroprotective method to reduce behavioral dysfunction following an acute ischemic stroke. We evaluated the effects of continuous wave (CW) or pulse wave (P) NILT administered transcranially either 6 or 12 h following embolization, on behavioral outcome. For the studies, we used the rabbit small clot embolic stroke model (RSCEM) using three different treatment regimens: 1) CW power density of 7.5 mW/cm(2); 2) P1 using a frequency of 300 mus pulse at 1 kHz or 3) P2 using a frequency of 2 ms pulse at 100 Hz. Behavioral analysis was conducted 48 h after embolization, allowing for the determination of the effective stroke dose (P(50)) or clot amount (mg) that produces neurological deficits in 50% of the rabbits. Using the RSCEM, a treatment is considered beneficial if it significantly increases the P(50) compared with the control group. Quantal dose-response analysis showed that the control group P(50) value was 1.01+/-0.25 mg (n=31). NILT initiated 6 h following embolization resulted in the following P(50) values: (CW) 2.06+/-0.59 mg (n=29, P=0.099); (P1) 1.89+/-0.29 mg (n=25, P=0.0248) and (P2) 1.92+/-0.15 mg (n=33, P=0.0024). NILT started 12 h following embolization resulted in the following P(50) values: (CW) 2.89+/-1.76 mg (n=29, P=0.279); (P1) 2.40+/-0.99 mg (n=24, P=0.134). At the 6-h post-embolization treatment time, there was a statistically significant increase in P(50) values compared with control for both pulse P1 and P2 modes, but not the CW mode. At the 12-h post-embolization treatment time, neither the CW nor the P1 regimens resulted in statistically significant effect, although there was a trend for an improvement. The results show that P mode NILT can result in significant clinical improvement when administered 6 h following embolic strokes in rabbits and should be considered for clinical development.

Interaction of hepatitis C virus F protein with prefoldin 2 perturbs tubulin cytoskeleton organization

By use of the yeast two-hybrid system, hepatitis C virus (HCV) F protein was found to interact with a cellular protein named prefoldin 2. The interaction was confirmed by confocal immunofluorescence microscopy as well as coimmunoprecipitation experiments. Prefoldin 2 is a subunit of a hexameric molecular chaperone complex, named prefoldin, which delivers nascent actin and tubulin proteins to the eukaryotic cytosolic chaperonin for facilitated folding. Functional prefoldin spontaneously assembles from its six subunits (prefoldin 1-6). In the yeast three-hybrid system, it was found that expression of HCV F protein impeded the interaction between prefoldin 1 and 2. By performing immunofluorescence experiment and non-denaturing gel electrophoresis, it was shown that expression of HCV F protein resulted in aberrant organization of tubulin cytoskeleton. Since HCV replication requires intact microtubule and actin polymerization, HCV F protein may serve as a modulator to prevent high level of HCV replication and thus contributes to viral persistence in chronic HCV infection.

Identification of Turnip mosaic virus Isolates Causing Yellow Stripe and Spot on Calla Lily

Two virus cultures, RC4 and YC5, were isolated in Taiwan from calla lily (Zantedeschia spp.) cv. Black magic displaying yellow spot and stripe on leaves. Both isolates were mechanically transmitted to various hybrids of Zantedeschia and induced systemic symptoms similar to those observed on diseased Black magic. In addition to Zantedeschia spp., the two virus isolates also infected several cruciferous species and induced mosaic symptoms. Electron microscopy revealed the presence of flexuous virus particles about 750 nm in length. The two isolates were propagated in and purified from mustard plants and were used as immunogens for production of antisera in rabbits. In enzyme-linked immunosorbent assay and sodium dodecyl sulfate-immunodiffusion tests, both antisera reacted strongly with their homologous antigens and with antigens of two Turnip mosaic virus (TuMV) isolates from radish (TuMV-R) and lisianthus (TuMV-L), but not with 21 other different potyviruses tested. In reciprocal tests, antisera against TuMV-R and TuMV-L also reacted strongly with RC4 and YC5 antigens, indicating that these two calla lily isolates are serologically indistinguishable from other known TuMV strains. Cloning and sequence analyses confirmed that both isolates shared 95 to 99% of deduced amino acid sequence identities in the coat protein genes with those of various known TuMV strains. This investigation represents the first record of the natural infection of TuMV in calla lily.

Abolishment of the interaction between cyclin-dependent kinase 2 and Cdk-associated protein phosphatase by a truncated KAP mutant

The cyclin-dependent kinase (Cdk)-associated protein phosphatase (KAP) is a human dual-specificity protein phosphatase that dephosphorylates Cdk2 on a conserved threonine residue, T160, in a cyclin dependent manner. Several aberrant KAP transcripts with characteristic deletion regions have been identified in hepatocellular carcinoma tissues. In this report, we demonstrated that multiple aberrant KAP transcripts were also present in a hepatoblastoma cell line (HepG2), albeit harboring a totally different set of deletions. By performing yeast two-hybrid and co-immunoprecipitation experiments, a KAP-Cdk2 interaction domain located in the amino acid 1-34 region was identified. This interaction domain was different from the major protein interface deduced from crystal structure analysis. Using a yeast three-hybrid system, it was shown that the presence of a truncated KAP mutant encoding this interaction domain abolished the wild-type KAP-Cdk2 interaction. In conclusion, a previously unidentified KAP-Cdk2 interaction domain was discovered. Truncated KAP mutants containing this domain interfered with the wild-type KAP-Cdk2 interaction.

Relationship between reproductive performance and immunity in Taiwan country chickens

Two experiments were conducted to investigate the relationships among reproductive performance, serum gamma-globulin level, carbon clearance ability, and immune responses to phytohemagglutinin and SRBC in the Taiwan Country chicken. In Experiment 1, 480 pullets from 82 sires and 204 dams were used to evaluate the relationship between reproductive performance and immunity. In Experiment 2, 480 pullets, offspring from 55 sires and 173 dams expressing a high or low percentage of serum gamma-globulin and their reciprocal crosses, were used to examine if the level of serum gamma-globulin is associated with reproductive performance and immunity. Results of these experiments indicated that 1) the Taiwan Country chicken had relatively high serum gamma-globulin level compared with those in other reports, 2) serum gamma-globulin level in the Taiwan Country chicken is heritable with an estimate around 0.3 to 0.4, and 3) the high serum gamma-globulin level is genetically associated with low fertility.

Serological and Molecular Characterization of Peanut chlorotic fan-spot virus, a New Species of the Genus Tospovirus

ABSTRACT To clarify the serological relationship of Peanut chlorotic fan-spot virus (PCFV) with other tospoviruses, antisera were produced against the nucleocapsid (N) proteins of this virus and tospoviruses from four serogroups including Tomato spotted wilt virus (TSWV), Impatiens necrotic spot virus (INSV), Groundnut ringspot virus (GRSV), and Watermelon silver mottle virus (WSMoV). In immunodiffusion tests, the antisera only reacted with their homologous antigens. Similar results were noticed in indirect enzyme-linked immunosorbent assay and immunoblot tests, with the exception that strong cross-reactions were observed in heterologous combinations between TSWV and GRSV. The results indicated that the N protein of PCFV is not serologically related to those of the tospoviruses from the four serogroups. To further characterize the virus, viral S double-stranded RNA was extracted from PCFV-infected Chenopodium quinoa and used for cDNA cloning and sequencing. The full-length viral strand of the S RNA was determined to be 2,833 nucleotides, with an inverted repeat at the 5' and 3' ends and two open reading frames in an ambisense arrangement. The 3'-terminal sequence (5'-AUUGCUCU-3') of the viral S RNA is identical to those of other tospoviruses, indicating that PCFV belongs to the genus Tospovirus. The N and the NSs proteins of PCFV share low amino acid identities (22.3 to 67.5% and 19.3 to 54.2%) with those of reported tospoviruses, respectively. The phylogenetic dendrogram of the N gene of PCFV compared with those of other tospoviruses indicates that PCFV is distinct from other tospoviruses. In hybridization analyses, an N gene cDNA probe of PCFV did not react with viral RNAs of TSWV, GRSV, INSV, and WSMoV, and vice versa. Thus, based on these results, we conclude that PCFV is a new tospovirus species.

Serotonin 6 receptor polymorphism in schizophrenia: frequency, age at onset and cognitive function

The relative abundance of serotonin 6 receptor (5HT6) in some limbic regions and the high affinity of some antipsychotics for 5HT6 suggest that the 5HT6 gene might play a role in the pathogenesis of schizophrenic disorders. A recent study reported an association between a C267T polymorphism of the 5HT6 gene and schizophrenia. In order to test whether the 5HT6 gene plays a role in the pathogenesis of schizophrenic disorders, patients (n = 148) and control subjects (n = 160) were genotyped for 5HT6. We also investigated the relationship between genotypes and patients' age at onset and cognitive function in schizophrenic patients. Cognitive function in the patients was evaluated by the Mini-Mental State Examination (MMSE). The results demonstrated no significant differences in genotype or allele frequencies between controls and patients. In the patient group, age at onset and MMSE score did not differ significantly among the three 5HT6 genotpyes. The results of this study suggest that the 5HT6 C267T polymorphism plays no major role in susceptibility to the development of schizophrenia and is not related to cognitive impairment or age at onset in schizophrenic patients. Further studies of the relation between 5HT6 polymorphism and the symptoms and the therapeutic response in schizophrenic patients may help to elucidate the role of 5HT6 in the pathogenesis of schizophrenia.

Phase determination and extension using X-ray multiple diffraction and the maximum-entropy method

The extension of the phases of the structure factors of the organic crystal C(25)H(25)NO(2) from 77 starting individual phases using the maximum-entropy method is reported. These starting phases were determined from 90 experimental triplet phases calculated from 215 measured psi-scan three-beam and four-beam diffraction profiles obtained with a rotating-anode X-ray source, where the psi scans were around the reciprocal-lattice vectors of the 001, 002 and 003 reflections. The extension of the structure factors with phase values was carried out using the maximum-entropy method for 2040 measured two-beam Bragg diffraction intensities with 77 starting phases and the symmetry of the space group as the constraints. Use of structure-factor triplets as constraints for entropy maximization was also attempted. The minimum chi(2) criteria were applied to the maximum-entropy extrapolation to discern the best phase set to be used as the new constraints for the next step of generating new phases. With this phase-extension procedure, more than 100 phases were determined and an electron-density map at 1.97 A was deduced.

Completion of the Genome Sequence of Watermelon silver mottle virus and Utilization of Degenerate Primers for Detecting Tospoviruses in Five Serogroups

ABSTRACT The nucleotide sequence of the L RNA of Watermelon silver mottle virus (WSMoV) was determined. Combined with the previous work on M and S RNAs, the whole genomic sequence of this member of the genus Tospovirus was completed. The L RNA is 8,917 nucleotides in length, with one large open reading frame encoding a translation product of 2,878 amino acids (331.8 kDa) on the viral complementary strand. The L protein shares amino acid identities of only 44.3 and 46.5% with Tomato spotted wilt virus (TSWV) and Impatiens necrotic spot virus, respectively; but an amino acid identity of 91.3% with Peanut bud necrosis virus. Among the sequenced tospoviruses, L protein was the most conserved gene product, whereas the nonstructural S protein was generally the most variable. Comparison of the deduced L protein of WSMoV with those of other members of the family Bunyaviridae revealed that its amino acid sequence includes the reported conserved motifs of RNA-dependent RNA polymerases. To develop a method for detecting tospo-viruses by reverse transcription-polymerase chain reaction (RT-PCR), two pairs of degenerate primers were designed from conserved regions of the L genes and used to amplify the corresponding regions of the L genes from total RNAs extracted from plant tissues infected with five serologically distinct tospoviruses. The DNA fragments obtained were identified as those of tospoviruses by restriction enzyme digestion and DNA sequencing. For field samples, watermelon and wax gourd infected with WSMoV, and lisianthus infected with TSWV were also successfully detected by these two pairs of degenerate primers, with a sensitivity similar to N-gene-specific primers. The results indicated that the RT-PCR with the degenerate primers is a fast and reliable method for detecting tospoviruses in different serogroups.

Anomalous dispersion behavior of multiple-wave X-ray diffraction at absorption edges: determination of phase change at resonance

The effects of anomalous dispersion (resonance) on multiple reflection of x rays and their interference in crystals at atomic absorption edges are studied. Intensity ratios of two inversion-symmetry-related multiple diffractions at or near absorption edges exhibit highly phase-sensitive profiles with strong asymmetric characteristics, unlike those far from the edges. A new resonance perturbation Bethe approach is developed to explain this behavior. This leads to direct determination of the phase change for x-ray reflections at resonance.

Identification of victims of the 1998 Taoyuan Airbus crash accident using DNA analysis

In February 1998 a civilian aeroplane carrying 196 individuals crashed in Taiwan and killed another 6 people on the ground. Although there were dental and medical records, fingerprints, photographic evidence and personal effects to identify some of the victims, DNA analysis was required to further identify severely damaged remains. From the 202 people known to have perished in the plane crash, a total of 685 fragments of human remains were subjected to DNA analysis. The analysis was carried out using nine microsatellite loci, plus amelogenin to cluster the 685 fragments into 202 groups, accounting for all the victims. To establish genetic relatedness of the victims to other victims and living relatives, additional DNA loci were used. In this case the paternity index was increased by using HLA DQA1 plus Polymarker. The same 16 DNA loci were used to test blood samples from 201 relatives to establish parent/child and sibling relationships. With the exception of 19 victims identified by non-genetic evidence, 183 victims were successfully identified by DNA typing with relatively high values of paternity index by the direct or indirect comparison of relatives. The 202 victims were from 37 different families, ranging in size from 2 to 13 members and 74 individuals known to be unrelated to any other victim. The DNA from living relatives was used to identify one member of a family group, from which other victims of the family could be identified. ABO blood group information was further used to confirm genetic relatedness within families. A comparison of the DNA profiling results to the ABO blood group of the victims showed no discrepancies with the exception of two mutations in the FGA locus. In cases of severely damaged victims from a plane crash, DNA analysis proved to be the best choice to identify victims.

DNA short tandem repeat profiling of Chinese population in Taiwan determined by using an automated sequencer

We performed a population study on a Taiwan population using a set of nine short tandem repeat (STR) loci and the amelogenin locus. Allele and genotype frequencies of the STR systems D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820 were determined by polymerase chain reaction followed by automated sequencer analysis. A total of 80 alleles could be observed, using all systems, in a population of 500 individuals. No new intermediate fragments were found in these systems. Allele frequencies showed no deviation from the Hardy-Weinberg equilibrium. The mean exclusion power (MEP) ranged from 0.294 for TPOX to 0.711 for FGA (the combined MEP was > 0.999), the discriminating power (DP) ranged from 0.782 for TPOX to 0.964 for FGA, (the combined DP was > 0.99999999949).

Vaginal lubricants for the infertile couple: effect on sperm activity

OBJECTIVE

To determine the effects of natural vegetable oils and vaginal lubricants on sperm motion and viability.

DESIGN

Four widely used vaginal lubricants (K-Y Jelly, Astroglide, Replens, and Touch) and two vegetable oil products that have been used as vaginal lubricants were purchased through local vendors. Sperm was obtained by masturbation without lubrication from normal, healthy donors. Lubricants were mixed with sperm from individual donors and the effects on sperm motility were determined at 1, 15, 30, and 60 minutes.

SETTING

Southwestern Fertility Associates of The University of Texas Southwestern Medical Center at Dallas.

MAIN OUTCOME MEASURES

Sperm motility was evaluated by manual motility counts and by computer-assisted semen analysis. Sperm viability was evaluated with Hoechst 33258 dye. The effects of the various lubricants were compared with those of a spermicidal agent, Gynol II (negative control) and Ham's F-10 (positive control).

RESULTS

Commercial lubricants inhibited sperm motility by 60-100% after 60 minutes of incubation. Sperm exposed to Replens or Astroglide were nonmotile and nonviable after incubation for 60 minutes, similar to the control, nonoxynol-9 containing product Gynol II. Canola oil had no detrimental effects and was indistinguishable from Ham's F-10 in terms of sperm viability and motility.

CONCLUSIONS

For couples with infertility, the use of vaginal lubricants during intercourse is not recommended. In cases where a lubricant is required, careful selection can maximize sperm motility and viability.

Interferometric phase locking of two electronic oscillators with a cascade electro-optic modulator

An optical-type electrical phase-locked-loop system based on a cascade electro-optic modulator has been demonstrated. By using this technique, a set of optical-type phase detectors, operating at any harmonic frequencies of two applied phase-modulation signals, has been implemented.

Experience of six patients with Vibrio vulnificus septicemia

Vibrio vulnificus, a halophilic lactose fermenting vibrio, is a virulent pathogen for men and is frequently associated with overwhelming infections of areas other than the gastrointestinal tract. We encountered six cases of Vibrio vulnificus septicemia in Veterans General Hospital-Taipei over the past four years. All were admitted through the emergency room and presented with urgent conditions on arrival. The patients also demonstrated preexisting liver function impairment (either hepatic disease or chronic alcohol consumption). Five subjects had an apparent history of exposure to marine environments: one fisherman with pre-existing wounds and four others with previous consumption of poorly cooked seafood. Characteristic hemorrhagic bullous lesions were found in 5 cases. In all, 4 patients (67%) died with three of the cases within 24 hours of hospitalization. Misdiagnosis and delayed treatment were the most common causes. In conclusion, when patients present with sepsis and/or characteristic cutaneous lesions, particulously those with underlying liver disease and a history of marine exposure, clinicians should be alerted to this potentially fatal infection and should commence appropriate assessment and treatment immediately.

Mollaret's meningitis: a case report and literature review

Mollaret's meningitis is a rare syndrome with characteristic features. We present a case with interesting clinical course and cerebrospinal fluid studies. The patient was admitted to Veterans General Hospital-Taipei 6 times between May, 1984 and May, 1991 because of recurrent meningitis (Mollaret's meningitis). No causative etiology was identified although a series of investigations were performed, including studies of the blood and CSF, roentgenogram and nuclear scintinographs. To date, there has been no standard therapeutic modality for this disease. We use aspirin for his symptomatic control with satisfactory result though colchicine has been reported as being effective also.

Overview of viridans streptococcal endocarditis: clinical analysis of 99 cases

A total of 99 cases of viridans streptococcal endocarditis encountered during the period of 1973 and 1990 at the Veterans General Hospital-Taipei were reviewed to evaluate its prognostic factors. Applying strict clinical and laboratory criteria, 24 cases were categorized as definite, 44 probable, 23 possible and 8 likely. The symptoms were frequently subtle and atypical but initial laboratory tests gave useful indications: 69.1% with leukocytosis, 78% with anemia, 58.5% with elevation of LDH level, 88.9% with elevation of ESR value and 100% with elevation of CRP level. Furthermore, 32.4% of the cases demonstrated proteinuria and 67.4% microscopic hematuria. Seventy-three of the subjects had a history of underlying heart disease, predominantly rheumatic heart disease. Histological examination and echocardiography revealed that 51 patients suffered from vegetative endocarditis, 7 (13.7%) of whom were found to have anatomically confirmed vegetations without initial echocardiographic evidence, Vascular events were seen in 61 cases (61.6%): peripheral stigmata (32 cases), cerebral vascular accidents (17 cases), pulmonary embolism (10 cases) and others (2 cases). The overall mortality rate was 18.2%. Congestive heart failure with embolization was the most common cause of death in this group. The presence of vegetation was not well correlated with embolic events. There was no statistically significant association between the mortality and the following characteristics: age, sex, underlying heart disease, evidence of echocardiographically detected vegetations, major surgical intervention and recurrent cases except for embolic events (p less than 0.01). In conclusion, viridans streptococcal endocarditis complicated embolic events usually presented with a fulminant course and a grave outcome.

Non-0:1 Vibrio cholerae bacteremia: a case report and literature review

We reported a case of non-0:1 group Vibrio cholerae septicemia with myelodysplatic syndrome in Taiwan. We also reviewed the other 22 reported cases of non-0:1 Vibrion cholerae septicemia found in the literature regarding its pathogenesis and treatment. The case mortality rate of these 23 cases was 47.8%. Most of them had immunocompromised diseases, particularly liver cirrhosis and hematologic malignancy. Therefore, the most important factor is the host defense. The cholera-like enterotoxin and E1-Tor-like hemolysin also play a major role, but whether the gall bladder plays a role in organ growth is still unclear. The incidence of gastroenteritis is not well understood because of the low incidence of non-0:1 V. cholerae gastroenteritis as compared with other factors such as shell-fish eating. Ampicillin as the sole antibiotic for non-0:1 V. cholerae is not efficacious. Tetracyclines or chloramphenicol is more effective for treatment.

Tetanus: 20 years of clinical experience

Tetanus remains a life-threatening disorder and its fulminating course always presents a challenge to the clinician. We retrospectively evaluated 56 patients with tetanus admitted to VGH-Taipei between 1971 and 1990. All of these patients with tetanus on admission showed typical features, with the most common initial complaints being lockjaw and dysphagia (82.6%). They were diagnosed on clinical identification rather than isolation of the causative agent. The laboratory tests were usually nonspecific and of limited value for diagnosis. Overall, 38 patients were seized with tetanus after an identified wound infection. The most common routes were puncture wound (28.3%) and abrasion wound (19.6%). The majority of patients became symptomatic within 10 days (56.5%) and the shorter interval reflected a more overwhelming course (p less than 0.05). Intravenous drug abusers and larger wounds had a poorer prognosis. The average mortality was 39.1% (18 out of 46 patients; male/female 12/6), with lack of statistical difference between sex and mortality (p greater than 0.5). The course of tetanus in the newborn and elderly was also more deadly (mortality rates of 83.3% and 55.6% respectively). Aspiration pneumonia and subsequent respiratory failure accounted for the most common cause (11 cases, 61.1%) of death. The mortality was still high (28.6%) from 1980-90 even with better supportive care and modern therapeutic equipment.

[Effect of increasing amounts of clonidine during hyperbaric tetracaine spinal anesthesia]

The effect of adding clonidine to hyperbaric tetracaine spinal anesthesia was investigated in 60 ASA class I-II patients scheduled for orthopedic and lower abdominal surgery. The subjects were randomly allocated into 4 groups. All patients received tetracaine 10 mg in 10% glucose solution 2 mL. Patients in group 1 received above medication and were the control group, patients in the other groups received tetracaine plus increasing dosages of clonidine: 15 microgram (Gr.2), 30 microgram (Gr.3), and 45 microgram (Gr.4). The segmental level of sensory loss was tested by the pinprick method using a 23 G needle. The three clonidine groups had significantly increased in the sensory regression time to L1 level (by 42, 47, 60% respectively), and also had significantly increased motor complete recovery time (by 48, 70, 74% respectively), but the incidence of hypotension and bradycardia was increased in the clonidine 0.045 mg group. It is concluded that addition of 15 or 30 microgram clonidine may be useful as a means of increasing the duration of hyperbaric tetracaine spinal anesthesia.