Biomedical subjects

Y Ou

Publications and source records attributed to Y Ou.

At least 19 recordsLinked to original sources

PubMed2006

Simian varicella virus gene 61 encodes a viral transactivator but is non-essential for in vitro replication.

Simian varicella virus (SVV) is closely related to varicella-zoster virus (VZV), the causative agent of chickenpox and shingles. The SVV and VZV gene 61 polypeptides are homologs of the HSV-1 ICP0, a viral transactivator which appears to play a role in viral latency and reactivation. In this study, the molecular properties of the SVV 61 were characterized. The SVV open reading frame (ORF) 61 encodes a 54.1-kDa polypeptide with 37% amino acid identity to the VZV 61. Homology to the HSV-1 ICP-0 is limited to a conserved RING finger motif at the amino terminus of the protein. A nuclear localization sequence (nls) at the carboxy-terminus directs the SVV 61 to the cell nucleus, while a SVV 61nls(-) mutant is confined to the cell cytoplasm. The SVV 61 transactivates its own promoter as well as SVV immediate early (IE, ORF 62), early (ORFs 28 and 29), and late (ORF 68) gene promoters in transfected Vero cells. The RING finger and nls motifs are required for efficient SVV 61 transactivation. The SVV 61 has no effect on the ability of the major SVV transactivator (IE62) to induce SVV promoters. Generation and propagation of a SVV gene 61 deletion mutant demonstrated that the SVV 61 is non-essential for in vitro replication. SVV gene 61 is expressed in liver, lung, and neural ganglia of infected monkeys during acute simian varicella.

Amino Acid Sequence↗

PubMed2004

Autoantigens of the nuclear pore complex.

The nuclear envelope (NE) is one of many intracellular targets of the autoimmune response in patients with autoimmune liver disease, systemic lupus erythematosus, and related conditions. In eukaryotic organisms the NE consists of five interconnected regions: an outer nuclear membrane (ONM) that is continuous with the endoplasmic reticulum, an intermembrane or perinuclear space, an inner nuclear membrane (INM) with a unique set of integral membrane proteins, the underlying nuclear lamina, and the pore domains that are regions where the ONM and INM come together. The pore domains are sites of regulated continuity between the cytoplasm and nucleus that are occupied by supramolecular structures, termed nuclear pore complexes (NPCs). Human autoantibodies identified to date bind to specific components in three of the five NE compartments. Autoantigen targets include the lamins A, B, and C of the nuclear lamina, gp210, p62 complex proteins, Nup153, and Tpr within the NPC, and LBR, MAN1, LAP1, and LAP2 that are integral proteins of the INM. Autoantibodies to these NE targets have been shown to be correlated with various autoimmune diseases such as primary biliary cirrhosis, other autoimmune liver diseases and systemic rheumatic diseases. Now that the proteome of the NE is more clearly defined, other autoantibodies to components in this cell compartment are likely to be defined.

Animals↗

PubMed2004

The nuclear pore complex protein Tpr is a common autoantigen in sera that demonstrate nuclear envelope staining by indirect immunofluorescence.

We studied the autoantigen targets of 75 human sera that had antibodies to the nuclear envelope (NE) as identified by indirect immunofluorescence (IIF) on HEp-2 cells. Several different IIF staining patterns could be identified when antibodies to different components of the nuclear membrane (NM) and nuclear pore complexes (NuPC) were identified: a smooth membrane pattern characteristic of antibodies to nuclear lamins, a punctate pattern typical of antibodies to the nuclear pore complex and more complex patterns that included antibodies to nuclear and cytoplasmic organelles. Western immunoblotting of isolated nuclear and NE proteins and immunoprecipitation of radiolabelled recombinant proteins prepared by using the full-length cDNAs of the Translocated promoter region (Tpr), gp210 and p62 were used to identify specific autoantibody targets. Fifty-two of the 75 (70%) sera bound to Tpr, 25 (33%) bound to lamins A, B or C, 15 (20%) reacted with gp210 and none reacted with p62. Sixteen (21%) did not react with any of the NE components tested in our assays. The clinical features of 37 patients with anti-NE showed that there were 34 females and three males with an age range of 16-88 years (mean 59 years). The most frequent clinical diagnosis (9/37 = 24%) was autoimmune liver disease (ALD; two with primary biliary cirrhosis), followed by seven (19%) with systemic lupus erythematosus (SLE), four (11%) with a motor and/or sensory neuropathy, three (8%) with anti-phospholipid syndrome (APS), two with systemic sclerosis (SSc), two with Sjögren's syndrome (SjS), and others with a variety of diagnoses. This report indicates that Tpr, a component of the NuPC, is a common target of human autoantibodies that react with the NE.

Adolescent↗

PubMed2003

Paraneoplastic limbic encephalitis masquerading as chronic behavioural disturbance in an adolescent girl.

AIM: To describe an unusual but treatable cause of behavioural disturbance in adolescence. METHODS: The case is reported of a 15-y-old girl presenting with acute confusion, memory problems and psychotic symptoms following an 18-mo history of change in personality, school failure and running away from home. A review of the literature is also presented. RESULTS: Microbiology, toxicology, computed tomography and magnetic resonance imaging did not show any pathology of the central nervous system. Bilateral ovarian immature teratomas were eventually diagnosed and removed. The rapid improvement in the patient's mental and cognitive functions after corticosteroid treatment and the abnormality shown on the single photon emission computed tomography suggested a diagnosis of paraneoplastic limbic encephalitis. CONCLUSION: Paediatricians and neurologists should be aware of this rare disease entity among the more common conditions of behavioural problems and substance abuse in adolescents.

Adolescent↗

PubMed2002

SCN5A is expressed in human jejunal circular smooth muscle cells.

Tetrodotoxin-resistant Na+currents are expressed in a variety of muscle cells including human jejunal circular smooth muscle (HJCSM) cells. The aim of this study was to determine the molecular identity of the pore-forming alpha-subunit of the HJCSM Na+ channel. Degenerate primers identified a cDNA fragment of 1.5 kb with 99% nucleotide homology with human cardiac SCN5A. The identified clone was also amplified from single smooth muscle cells by reverse transcriptase-polymerase chain reaction (RT-PCR). Northern blot analysis showed expression of full-length SCN5A. Laser capture microdissection was used to obtain highly purified populations of HJCSM cells. RT-PCR on the harvested cells showed that SCN5A was present in circular but not in longitudinal muscle. A similar result was obtained using a pan-Na+ channel antibody. The full-length sequence for SCN5A was obtained by combining standard polymerase chain reaction with 5' and 3' rapid amplification of cDNA end techniques. The intestinal SCN5A was nearly identical to the cardiac SCN5A. The data indicate that SCN5A is more widely distributed than previously thought and encodes the pore-forming alpha-subunit of the tetrodotoxin-resistant Na+ current in HJCSM cells.

Gene Expression Regulation↗

PubMed2002

Non-accidental carbon monoxide poisoning from burning charcoal in attempted combined homicide-suicide.

OBJECTIVE: To describe an emerging form of serious child abuse in combined homicide-suicide in Hong Kong. METHOD: This is a retrospective hospital chart review in a regional hospital in Hong Kong from January to December 2000. RESULTS: Eight children, with a mean age of 7.8 years (range 0.5-11 years), from four families were admitted to hospital because of non-accidental exposure to carbon monoxide when their parents attempted suicide by burning charcoal. A 7-year-old boy died on arrival. His 5.6-year-old sister and another 6-month-old boy had cerebral hypoxia on admission. Hyperbaric oxygen therapy was used in both cases, with rapid improvement, although there were persistent neurological deficits in the girl. The other children in the present study were asymptomatic and none had delayed neurological sequelae. Concomitant use of sedatives was also detected in three of the surviving patients. CONCLUSIONS: Non-accidental poisoning with carbon monoxide appears to be a new means of child abuse with potentially serious consequences. Concomitant intoxication with psychotropic drugs is common in such cases. The reason for parents killing their own children under such circumstances was unclear, but a desire to exact revenge on an estranged partner was suggested.

Adult↗

PubMed2001

SeO(2) induces apoptosis with down-regulation of Bcl-2 and up-regulation of P53 expression in both immortal human hepatic cell line and hepatoma cell line.

An immortal human hepatic cell line HL-7702 and human hepatoma cell line SMMC-7721 were treated with 3-30 microM SeO(2). SeO(2) at 30 microM markedly inhibited cell proliferation and viability, and prompted apoptosis of both normal hepatic and hepatoma cells after 48h treatment. SeO(2) could also down-regulate the Bcl-2 level, greatly in HL-7702 and slightly in SMMC-7721 cells, but up-regulate wild type P53 level a little in HL-7702 and significantly in SMMC-7721 cells. The Bcl-2/P53 value was closely correlated with the apoptotic rate as well as SeO(2) concentrations.

Apoptosis↗

PubMed2001

The cells of the rabbit meniscus: their arrangement, interrelationship, morphological variations and cytoarchitecture.

Four major morphologically distinct classes of cells were identified within the adult rabbit meniscus using antibodies to cytoskeletal proteins. Two classes of cell were present in the fibrocartilage region of the meniscus. These meniscal cells exhibited long cellular processes that extended from the cell body. A third cell type found in the inner hyaline-like region of the meniscus had a rounded form and lacked projections. A fourth cell type with a fusiform shape and no cytoplasmic projections was found along the superficial regions of the meniscus. Using a monoclonal antibody to connexin 43, numerous gap junctions were observed in the fibrocartilage region, whereas none were seen in cells either from the hyaline-like or the superficial zones of the meniscus. The majority of the cells within the meniscus exhibited other specific features such as primary cilia and 2 centrosomes. The placement of the meniscal cell subtypes as well as their morphology and architecture support the supposition that their specific characteristics underlie the ability of the meniscus to respond to different types of environmental mechanical loads.

Animals↗

PubMed2001

[Correlation of the metabolism of oxygen free radical in ovary, uterine muscle and vein blood with the pathogenesis of endometriosis or endometrioma].

OBJECTIVE: To investigate the correlation of metabolism disturbance of oxygen free radical (OFR) with endometriosis and endometrioma, to provide an evidence for the diagnosis and treatment. METHODS: (1) The lipid peroxide (LPO), selenium (Se), superoxide dismutase (SOD) and vitamin E (VE) levels were respectively in the vein blood, ovary tissue of the chocolate cyst wall and chocolate cyst fluid in 32 operated patients with endometriosis (endometriosis group). (2) The levels above were determined separately in 23 operated patients with endometrioma (endometrioma group) and 30 cases of hysteroma (control group). RESULTS: (1) The LPO levels in vein blood and ovary tissue of endometriosis group were (6.357 +/- 1.251) mumol/L and (3.735 +/- 1.546) nmol/g protein. Which significantly higher than those of control group (P < 0.01). On the other hand, the Se. SOD. VE levels in endometriosis group were significantly lower than those in control group (P < 0.01-< 0.05). (2) The LPO level in ovary chocolate cyst fluid was higher than that in vein blood itself and control group. (P < 0.01). (3) The LPO levels in vein blood and uterine muscle of endometrioma was (5.882 +/- 1.711) mumol/L and (2.937 +/- 1.577) nmol/g protein, they were higher-than these in control group (3.547 +/- 1.640) mumol/L, (1.754 +/- 0.833) nmol/g protein, (P < 0.01). While, the Se. VE. SOD level tween the SOD level in uterine muscle tissue of endometriomin vein blood is significantly higher than those in control group (P < 0.01). There is no difference bea and control group (P > 0.05). CONCLUSION: The endome triosis and endometrioma is related to the produce or metabolistic imbalance of oxygen free radical, and so to the increasing of lipid peroxide.

Endometriosis↗

PubMed2001

[Experimental study of interleukin-12 gene vaccines in the treatment of low-load malignant lymphoma (EL4)].

OBJECTIVE: Two kinds of murine interleukin-12 (mIL-12) fusion gene vaccines were used to treat the murine low-load malignant T cell lymphoma EL4 as minimal residual disease (MRD) model. METHODS: C57BL/6 synergistical mice were subcutaneously inoculated with 1 x 10(6) wild-type (wt) EL4 tumor cells as low-load lymphoma model treated with two mIL-12 gene vaccines. Package cell line PA317/12 producing mIL-12 retrovirus (RV) was used as in vivo vaccine and EL4 tumor cells transferred with mIL-12 gene as ex vivo vaccine. RESULTS: In both mIL-12 gene vaccine-treated groups, there was no tumor growth in 50% mice 60 days after inoculation. Nine of these no tumor growth mice were re-challenged with 5 x 10(5) wt EL4 cells, and 5 of them survived without tumors in another 60 days. All control mice died with tumors within one month after inoculation. Among those developed tumors in both vaccine-treated groups, the development of tumors was delayed, the survival period prolonged (P < 0.01), and the tumors size at death smaller (P < 0.05) as compared with the controls. In the long-survived vaccine-treated mice, no residual tumor cells were found by morphological examination. CONCLUSION: Both IL-12 gene vaccines can efficiently eliminate wt EL4 MRD in C57BL/6 mice.

Animals↗

PubMed2001

[Clinical analysis of 62 cases laryngeal papilloma in children].

OBJECTIVE: To investigate the clinical features of laryngeal papilloma in children. METHOD: In a group of 62 patients with laryngeal papilloma in children, the tumors of 28 patients were cut under the direct laryngoscope, 34 patients were treated with laryngeal micro-laser operation. RESULT: The post-operation followup ranged from 2 to 5 years, the cure rate of 2 years was 51.61%. CONCLUSION: The clinical features of this disease include rapid development, a large lesion, and it is often found in the infraglottic cavity. Furthermore, we believe that in order to eliminate the tumors more accurately and decrease recurrence, micro-laser surgery and the use of interferon is very necessary.

Adolescent↗

PubMed2000

Integrating centrosome structure with protein composition and function in animal cells.

The centrosome found in animal cells is a complex and dynamic organelle that functions as the major microtubule organizing center. Structural studies over the past several decades have defined the primary structural features of the centrosome but recent studies are now beginning to reveal structural detail previously unknown. Concurrent with these studies has been an explosion in the identification of the proteins that reside within the centrosome. Our growing understanding of how protein composition integrates with centrosome structure and hence with function is the focus of this review.

Animals↗

PubMed2000

A subset of centrosomal proteins are arranged in a tubular conformation that is reproduced during centrosome duplication.

The centrosome plays a fundamental role in organizing the interphase cytoskeleton and the mitotic spindle, and its protein complexity is modulated to support these functions. The centrosome must also duplicate itself once during each cell cycle, thus ensuring the formation of a bipolar spindle and its continuity through successive cell divisions. In this study, we have used a battery of antibodies directed against centrosomal components to study the general organization of the centrosome during the cell cycle and during the centrosome duplication process. We demonstrate that a subset of centrosomal proteins are arranged together to form a tubular pattern within the centrosome. The tubular conformation defined by these proteins has a polarity and is closed at one end. The centriole complement of the centrosome is normally placed near this end. We show that the "wall" of the tube is enriched in proteins such as CDC2, ninein, and pericentrin as well as gamma-tubulin. In addition, a subset of gamma-tubulin is localized to the "lumen" of the tube. We also demonstrate, for the first time, that antibody staining can be used to detect centrosome duplication allowing the identification of duplication intermediates. We show that one product of centrosome duplication is the replication of the tubular structure found within the centrosome. The position of the centriole duplexes prior to and during centrosome duplication is documented and a model of the morphogenesis of the centrosome during the duplication process is proposed.

Animals↗

PubMed2000

Anatomic considerations of costotransverse screw placement in the thoracic spine.

BACKGROUND: Numerous techniques have been reported to restore spinal stability and to correct spinal deformities, including rods with wires/hooks, and rods or plates with pedicular screws. It was thought that posterior fixation of the thoracic spine through the costotransverse joint may be another alternative. METHODS: Nine cadavers were obtained for study of screw fixation of the costotransverse joint for posterior thoracic instrumentation. The entrance point for screw insertion was designed to be at the posterior center of the clubbed extremity of the transverse process. From this point, a 3-mm drill bit was used to create the screw path penetrating the costotransverse joint and the ventral cortex of the rib. Under direct visualization of the costotransverse joint, the drill bit was directed parallel to the sagittal plane and toward the upper portion of the rib. Measurements included the screw path length and sagittal angulation. Also, the distance between the superior borders of the transverse process and the tubercle of the rib and the anatomic relationship of the drill bit exit to the intercostal vessels and nerves were evaluated. RESULTS: The maximum length of the screw path was found at T1 (19.7 mm), whereas the minimum length was noted at T4-T5 (13.9 mm). This value decreased gradually from T1 to T4-T5, and slightly increased to T10. The larger sagittal angles of the screw path were found at the levels of T1-T4 (78-86 degrees ), whereas the smaller were noted at the levels below T5 (53-61 degrees ). The mean distance between the superior borders of the transverse process and the tubercle of the rib was smaller at T1-T5 (0.2-0.4 mm), and significantly increased to T8 (5. 1 mm), and then slightly decreased to T10. The variation of this parameter was remarkable. All of the exit points for the drill bit were located in the upper half of the rib, and away from the intercostal vessels. CONCLUSIONS: The ideal screw orientation is parallel to the sagittal plane, and angled 80-90 degrees relative to the frontal plane for T1-T4 and 50-70 degrees for T5-T10 superiorly, starting at the posterior center of the transverse process. Costotransverse screw fixation in the thoracic spine may be an alternative to pre-existing methods.

Aged↗

PubMed2000

Septic arthritis in hemophilia with central venous catheter: a case report.

A case is reported of septic arthritis in a child with human immunodeficiency virus-negative hemophilia A associated with a Staphylococcus aureus catheter-associated septicemia. The infection occurred in relation to the use of a totally implantable central venous catheter. The organism was eventually eradicated with antibiotics injected via the catheter. With increasing use of such catheters in the hemophilic population, clinicians should be alerted to the possibility of septic arthritis for prompt diagnosis and treatment.

Adolescent↗

PubMed2000

[Therapeutic efficacy of microsphere-entrapped curcuma aromatica oil infused via hepatic artery against transplanted hepatoma in rats].

OBJECTIVE: To observe the therapeutic efficacy of microsphere-entrapped Curcuma aromatica oil (MS-CAO) infused via hepatic artery against transplanted hepatoma in rats. METHODS: One hundred duplicated rats bearing transplanted hepatoma were randomly divided into control group, CAO group, blank microsphere (B-MS) group, high-dose and low-dose MS-CAO groups. Each group included twenty rats. Normal saline (0.2-0.3 ml), CAO (10mg/kg), B-MS (10mg/kg) and MS-CAO (10mg/kg, 5mg/kg) were infused from gastroduodenal artery into hepatic artery, in five groups of rats respectively. The survival periods and the tumor growth rates and necrosis grades were compared in rats among five groups. RESULTS: Compared with the control group of rats, the tumor growth rates were significantly inhibited (1.23% +/- 0.66%, 4.86% +/- 1.47% vs 22.44% +/- 17.81%, F=10.21, P<0.01), the tumor necrosis grades were more extensive (Hc=23.63, P<0.01) and the survival periods were also prolonged (25.50 d +/- 3.89 d, 22.70 d +/- 3.92 d vs 11.70 d +/- 1.89 d, F=36.53, P<0.01) in either high-dose or low-dose MS-CAO group. The therapeutic effects of MS-CAO were superior to either CAO or B-MS. CONCLUSION: The therapeutic efficacy of MS-CAO infused via hepatic artery against hepatoma was much better than that of CAO or B-MS in the rats bearing transplanted hepatoma.

Animals↗

PubMed2000

[Expression of 2.1 kb enhancin gene fragment from Helicoverpa armigera granulosis virus in Escherichia coli].

The 2.1 kb fragment of enhancin gene from Helicoverpa armigera granulosis virus was inserted into vector pQE-30 and expressed successfully in E. coli M15(pREP4). The synergy of expression product(P78) on AcMNPV against the larvae of Plutella xylostella was also studied. The results indicated that the percentage of correct mortality of the larvae increased 27.88%-32.92% in 10 post-infection days.

Baculoviridae↗

PubMed1999

Mapping and characterization of the functional domains of the nucleolar protein RNA helicase II/Gu.

RNA helicase II/Gu (RH-II/Gu) is a nucleolar RNA helicase of the DEAD-box superfamily. In this study, the functional domains of RH-II/Gu molecule were mapped by fusing the protein or its deletion mutants with a green fluorescence protein and subsequently transfecting or microinjecting the recombinant constructs into HeLa cells. In addition to the identification of a nuclear localization signal (NLS) in the N-terminus and a nucleolar targeting signal in the central helicase domain, a hidden NLS and a nucleolar targeting signal were found in the C-terminal arginine/glycine-rich domain. RH-II/Gu colocalized with fibrillarin, a component of the dense fibrillar region of the nucleolus. Overexpression of the entire RH-II/Gu protein or specific domains of the protein in HeLa cells did not interfere with the normal distribution of fibrillarin. However, when the helicase domain was truncated, the distribution pattern of fibrillarin was distorted. Microinjection of the wild-type RH-II/Gu cDNA into the nucleus of HeLa cells did not disrupt normal cell growth. However, when cells were injected with mutant DNA, only a small percentage of HeLa cells progressed through the cell cycle. Analysis of centrosomes in transfected cells demonstrated that most of the mutant-expressing cells were arrested early in the cell cycle. The results suggest that each of the structural domains of RH-II/Gu is necessary for cell growth and cell cycle progression.

Binding Sites↗