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W Zuo

Publications and source records attributed to W Zuo.

At least 19 recordsLinked to original sources
PubMed2001

The LIS1-related protein NUDF of Aspergillus nidulans and its interaction partner NUDE bind directly to specific subunits of dynein and dynactin and to alpha- and gamma-tubulin.

The NUDF protein of Aspergillus nidulans, which is required for nuclear migration through the fungal mycelium, closely resembles the LIS1 protein required for migration of neurons to the cerebral cortex in humans. Genetic experiments suggested that NUDF influences nuclear migration by affecting cytoplasmic dynein. NUDF interacts with another protein, NUDE, which also affects nuclear migration in A. nidulans. Interactions among LIS1, NUDE, dynein, and gamma-tubulin have been demonstrated in animal cells. In this paper we examine the interactions of the A. nidulans NUDF and NUDE proteins with components of dynein, dynactin, and with alpha- and gamma-tubulin. We show that NUDF binds directly to alpha- and gamma-tubulin and to the first P-loop of the cytoplasmic dynein heavy chain, whereas NUDE binds directly to alpha- and gamma-tubulin, to NUDK (actin-related protein 1), and to the NUDG dynein LC8 light chain. The data suggest a direct role for NUDF in regulation of the dynein heavy chain and an effect on other dynein/dynactin subunits via NUDE. The interactions between NUDE, NUDF, and gamma-tubulin suggest that this protein may also be involved in the regulation of dynein function. Additive interactions between NUDE and dynein and dynactin subunits suggest that NUDE acts as a scaffolding factor between components.

Active Transport, Cell Nucleus↗
PubMed2001

The Aspergillus cytoplasmic dynein heavy chain and NUDF localize to microtubule ends and affect microtubule dynamics.

Cytoplasmic dynein is a multisubunit, minus end-directed microtubule motor that uses dynactin as an accessory complex to perform various in vivo functions including vesicle transport, spindle assembly, and nuclear distribution [1]. We previously showed that in the filamentous fungus Aspergillus nidulans, a GFP-tagged cytoplasmic dynein heavy chain (NUDA) forms comet-like structures that exhibited microtubule-dependent movement toward and back from the hyphal tip [2]. Here we demonstrate that another protein in the NUDA pathway, NUDF, which is homologous to the human LIS1 protein involved in brain development [3, 4], also exhibits such dynamic behavior. Both NUDA and NUDF are located at the ends of microtubules, and this observation suggests that the observed dynamic behavior is due to their association with the dynamic microtubule ends. To address whether NUDA and NUDF play a role in regulating microtubule dynamics in vivo, we constructed a GFP-labeled alpha-tubulin strain and used it to compare microtubule dynamics in vivo in wild-type A. nidulans versus temperature-sensitive loss-of-function mutants of nudA and nudF. The mutants showed a lower frequency of microtubule catastrophe, a lower rate of shrinkage during catastrophe, and a lower frequency of rescue. The microtubules in the mutant cells also paused longer at the hyphal tip than wild-type microtubules. These results indicate that cytoplasmic dynein and the LIS1 homolog NUDF affect microtubule dynamics in vivo.

Aspergillus nidulans↗
PubMed2001

Nuclear stopping as a probe for in-medium nucleon-nucleon cross sections in intermediate energy heavy ion collisions.

Using an isospin-dependent quantum molecular dynamics, nuclear stopping in intermediate heavy ion collisions has been studied. The calculation has been done for colliding systems with different neutron-proton ratios in beam energy ranging from 15 MeV/ u to 150 MeV/ u. It is found that, in the energy region from above Fermi energy to 150 MeV/ u, nuclear stopping is very sensitive to the isospin dependence of in-medium nucleon-nucleon cross section, but insensitive to symmetry potential. From this investigation, we propose that nuclear stopping can be used as a new probe to extract the information on the isospin dependence of in-medium nucleon-nucleon cross section in intermediate energy heavy ion collisions.

Journal Article↗
PubMed2001

[Clinical significance of sentinel lymph node biopsy for breast cancer].

OBJECTIVE: To study the significance of sentinel lymph node(SLN) biopsy (SLNB) in determining the extent of axillary dessection for cN0 breast cancer patients. METHODS: In 96 patients with cN0 breast cancer, sentinel lymph nodes identified by patent blue-V or methylene blue staining were excised for biopsy. patients then received operations for breast cancer including axillary dessection. RESULTS: SLN was identified in 91 patients. The total number of SLN identified was one in 54 cases(59.3%), 2 in 23 cases(25.3%) and > or = 3 in 14 cases(15.4%). In 24 of the 91 patients, SLN was positive for metastasis. In 13 the 24 patients, only SLN provided evidence of lymph node metastasis. The sensitivity of SLN biopsy was 87.5%, the specificity was 100%. It had 100% positive predictability and 95.7% negative predictability of lymph node metastasis. The accuracy rate of intraoperative imprint cytology examination of SLN was 92.1%, with a false negative rate of 10.0% and a false positive rate of 7.1%. The accuracy rate of frozen-section examination of SLN was 98.7% during operation, with a false negative rate of 5.0% but without false positive result. Immunohistochemical assay did not help demonstrate metastasis in SLN negative on routine pathologic examination. CONCLUSION: The SLN status can generally be a representation of axillary metastasis, SLNB is useful to determine the extent of axillary dessection in cN0 breast cancer patients. Methylene blue is as effective as patent blue-V in the identification of SLN.

Adult↗
PubMed2000

Dynamics of cytoplasmic dynein in living cells and the effect of a mutation in the dynactin complex actin-related protein Arp1.

Cytoplasmic dynein is a minus-end-directed microtubule motor that participates in multiple cellular activities such as organelle transport and mitotic spindle assembly [1]. To study the dynamic behavior of cytoplasmic dynein in the filamentous fungus Aspergillus nidulans, we replaced the gene for the cytoplasmic dynein heavy chain, nudA, with a gene encoding a green fluorescent protein (GFP)-tagged chimera, GFP-nudA. The GFP-NUDA fusion protein is fully functional in vivo: strains expressing only the GFP-tagged nudA grow as well as wild-type strains. Fluorescence microscopy showed GFP-NUDA to be in comet-like structures that moved in the hyphae toward the growing tip. Retrograde movement of some GFP-NUDA comets after they arrived at the tip was also observed. These dynamics of GFP-NUDA were not observed in cells treated with a microtubule-destabilizing drug, benomyl, suggesting they are microtubule-dependent. The rate of GFP-NUDA tip-ward movement is similar to the rate of cytoplasmic microtubule polymerization toward the hyphal tip, suggesting that GFP-NUDA is associated and moving with the polymerizing ends of microtubules. A mutation in actin-related protein Arp1 of the dynactin complex abolishes the presence of these dynamic GFP-NUDA structures near the hyphal tip, suggesting a targeting role of the dynactin complex.

Aspergillus nidulans↗
PubMed2000

CD34+ cells derived from fetal liver contained a high proportion of immature megakaryocytic progenitor cells.

Endoreplication and maturation of the megakaryocyte (MK) may be retarded or delayed during ontogenesis. In this study, CD34+ cells were isolated from both human fetal liver and adult bone marrow and incubated with thrombopoietin (TPO). The cell number, morphological characteristics, platelet-associated antigen phenotype, maturation stage and DNA ploidy of CD41+ cells were examined from day 0 to day 12 in culture. 1) TPO stimulated the proliferation of fetal liver (FL)-derived CD34+ cells with a mean 73.14-fold increase of CD41+ cells after 12 d in culture. Adult BM-derived CD34+ cells increased only slightly, with a mean 8.18-fold increase of CD41+ cells. 2) Although the membrane phenotype of both FL CD34+-derived MKs and BM CD34+ -derived MKs analyzed with CD41a, CD42a, CD61 and CD34 were similar, all FL CD34+-derived MKs were in maturation stage I and II and in low ploidy (<4N) class. By comparison, BM CD34+ MKs possessed 15% MKs in maturation stage III and IV and with 23% MKs in high ploidy class ( > 4N). 3) Most of cultured FL-derived CD34+ cells did not have a well developed demarcation system (DM) and numerous alpha-granules after 12 d incubation. von Willebrand factor (vWF) appeared earlier on the cultured BM-derived CD34+ cells than on FL-derived CD34+ cells. 4) The expression of both cyclin E and cyclin B1 progressively increased in FL CD34+ cells induced by TPO during 12 d in culture. 5) The expression of cyclin D1 gradually decreased in FL CD34+ cells induced by TPO over 12 d incubation. 6) Immunocytochemical analysis showed that cyclin D3 was detected only in cytoplasm of cultured FL-derived CD34+ cells, whereas in both cytoplasm and nuclei of cultured BM-derived CD34+ cells. These data suggest that FL-derived CD34+ cells contain a high proportion of immature megakaryocytic progenitor cells. It further suggests that TPO can push these progenitor cells into proliferation by upregulating the expression of cyclins B1 and E, and drive a high proportion of cells into megakaryocytic lineage.

Adult↗
PubMed2000

[Evaluation of autonomic nervous function with heart rate variability and cardiovascular reflex tests in type II diabetes mellitus patients].

OBJECTIVE: To evaluate autonomic nervous function in simple diabetes mellitus patients, diabetic nephropathy(DN) patients and diabetes mellitus patients with accompanying coronary heart disease(DC) by studying heart rate variability (HRV) and cardiovascular reflex tests. METHODS: 57 type II diabetes mellitus patients were divided into 3 groups: 29 of simple diabetes mellitus, 17 of DC, and 11 of DN. The three groups were matched to 15 healthy controls for age, HRV and three cardiovascular reflex tests were performed in all the patients. RESULTS: The overall frequency of abnormal autonomic nervous function in 57 diabetes mellitus patients was 45.6%. All the diabetes mellitus groups especially the DN group were lower than a normal control group in time domain indexes and nonlinear dynamics indexes. As the patterns of R-R interval Poincare plots were concerned, the control group was mainly of comet-shaped pattern, the simple diabetes mellitus group was mainly of torpedo-shaped pattern, while the DN group and the DC group had more irregular patterns. CONCLUSION: Decrease in HRV is an early clinical marker for evolving diabetic autonomic neuropathy. This method may be helpful for evaluating organ dysfunction in diabetes mellitus patients.

Adult↗
PubMed2000

[Endometrial nuclear progesterone receptors in infertile women].

OBJECTIVE: To investigate the endometrial nuclear progesterone receptors (PgR) as well as its relationship with retarded endometrial development (RED) in infertile women. METHODS: The progesterone profile, endometrial nuclear progesterone receptors (PgR) and endometrial biopsies were studied by using (125)I radioimmunoassay and immunohistochemical technique in 53 infertile women during median luteal phase. When the endometrial dating lagged 2 days behind the dating as determined by luteinizing hormone (LH) surge, diagnosis of luteal phase defect (LPD) was made. According to progesterone profile and endometrial morphology, the patients were divided into three groups: normal, luteal phase defect (LPD) and pseudocorpus luteum insufficiency (PLI). RESULTS: During median luteal phase, RED were found in all of 24 cases with LPD and PLI, but PgR contents were different in them. Mean progesterone profile of 9 cases of PLI cycles was normal (60.2 nmol/L) but the endometrial nuclear PgR appeared to be prominently lower than in normal cycles during the median luteal phase (P < 0.01). Average progesterone level of 15 cases of LPD cycles were significantly lower (29.9 nmol/L) but endometrial nuclear PgR were similar to normal group (P > 0.05). CONCLUSION: Retarded endometrial development may have different causes. Measurement of endometrial nuclear PgR is of assistance in differential diagnosis.

Adult↗
PubMed1999

Isolation of a new set of Aspergillus nidulans mutants defective in nuclear migration.

In the filamentous fungus Aspergillus nidulans, nuclear migration in the germ tube is mediated by cytoplasmic dynein. We have previously reported the characterization of four nud (nuclear distribution) genes, nudA, nudC, nudF and nudG, involved in this process. The nudA and nudG genes respectively encode for the heavy chain and the 8-kDa light chain of cytoplasmic dynein. In this work, we describe an improved method for the isolation of nud mutants that has led to the identification of at least ten additional nud loci. We have cloned one of the genes, nudK, and determined that it encodes the actin-related protein Arp1, which is a component of the dynactin complex. This provides the first evidence that dynactin is involved in nuclear migration in A. nidulans.

Actins↗
PubMed1999

[The significance of endometrial biopsy during luteal median phase in diagnosis of luteal function].

OBJECTIVE: To investigate the significance of progesterone profile and endometrial biopsy during luteal median phase in diagnosis of luteal function. METHODS: The progesterone profile during median luteal phase and endometrial histology during median and late luteal phase of 53 infertile women with infertile and recurrent abortion for unknown reasons were studied. RESULTS: Retarded endometrial development occurred in the median luteal phase in 24 of the 53 cases, 9 of which lasted into the late phase. The average progesterone profile of these patients was markedly lower compared with the control group (P < 0.05). However, the average progesterone profile remained normal in the other 13 cases, in whom, RED got normalized in the late luteal phase. Endometrial biopsies taken during the median and late luteal phase from the rest of 29 cases were normal. CONCLUSIONS: In patients with retarded endometrial development during the full luteal phase, luteal function was decreased, but in patients with retarded endometrial development only during the median luteal phase, luteal function appeared to be normal.

Abortion, Habitual↗
PubMed1999

[Observation on the clinical symptoms and sporocyst excretion in human volunteers experimentally infected with Sarcocystis hominis].

AIM: To investigate the excretion of sporocysts and clinical manifestations in humans experimentally infected of Sarcocystis hominis. METHODS: Three volunteers were infected by eating raw beef containing cysts of S. hominis. One ingested about 1,567 cysts in skeletal muscles of a naturally infected cattle; two volunteers each ingested about 14,740 cysts from an experimentally infected water buffalo meat. Fecal examination by zinc sulfate flotation method was conducted daily since d4 postinfection (pi). RESULTS: Free sporocysts and oocysts were found in their faeces from d11-40, d12-23, d10-30 pi, and peaked at d18, d14, d14. All of them presented clinical symptoms such as abdominal pain, distension, watery diarrhea and eosinophilia 1 wk approximately 4 wk pi and were spontaneously cured within 29 days pi without taking any medicine. CONCLUSION: All the experimentally infected persons had gastrointestinal symptoms and passed sporocysts and oocysts in faeces 10-12 days after infection and persisted for 11-29 days.

Adult↗
PubMed1998

Overexpression of transforming growth factor beta1 in arterial endothelium causes hyperplasia, apoptosis, and cartilaginous metaplasia.

Uninjured rat arteries transduced with an adenoviral vector expressing an active form of transforming growth factor beta1 (TGF-beta1) developed a cellular and matrix-rich neointima, with cartilaginous metaplasia of the vascular media. Explant cultures of transduced arteries showed that secretion of active TGF-beta1 ceased by 4 weeks, the time of maximal intimal thickening. Between 4 and 8 weeks, the cartilaginous metaplasia resolved and the intimal lesions regressed almost completely, in large part because of massive apoptosis. Thus, locally expressed TGF-beta1 promotes intimal growth and appears to cause transdifferentiation of vascular smooth muscle cells into chondrocytes. Moreover, TGF-beta1 withdrawal is associated with regression of vascular lesions. These data suggest an unexpected plasticity of the adult vascular smooth muscle cell phenotype and provide an etiology for cartilaginous metaplasia of the arterial wall. Our observations may help to reconcile divergent views of the role of TGF-beta1 in vascular disease.

Animals↗
PubMed1998

[Gastro-intestinal reconstruction by substitution of "O" shaped jejunum after total gastrectomy].

OBJECTIVE: To discuss a satisfying method for alimentary continuity reconstruction after total gastrectomy. METHOD: An "O" shaped jejunum pouch or a new "stomach" was constructed in between esophagus and duodenum after total gastrectomy. RESULTS: Thirty-nine cases of gastric malignant tumor were treated by this method. The 3 and 5 years disease free survival rate were 67.7% and 55.6%. All the patients recovered their normal meal habit (3 meals a day) within 6 months postoperatively. Compared with the preoperative and the postoperative (one year after operation), body weight is equal level, increasing and decreasing in 71.1%, 15.8% and 13.1% of the cases respectively. There were no posterior sternal pain and food or digestive fluid reflux, no dumping syndrome in these patients. The volume enlargement of the "new stomach" was observed obviously, especially in "stomach fundus". CONCLUSION: This operation is a satisfying method for alimentary canal reconstruction after total gastrectomy and it is worthy to be recommended in gastric surgery.

Adenocarcinoma↗
PubMed1997

The mouse estrogen receptor-related orphan receptor alpha 1: molecular cloning and estrogen responsiveness.

Estrogen receptor-related orphan receptor alpha 1 is a member of the steroid/thyroid nuclear receptor superfamily. We have previously cloned the human estrogen receptor-related orphan receptor alpha 1 (hERR alpha 1) cDNA and demonstrated that it enhances estrogen responsiveness of the lactoferrin gene promoter in transfected human endometrial carcinoma cells. In the present study, we used the hERR alpha 1 cDNA as a probe and isolated the mouse homologue of ERR alpha 1 from the cDNA libraries of the brain and kidney. Sequence comparison between human and mouse ERR alpha 1 (mERR alpha 1) revealed that the homologies are 89% in nucleotides and 97% in amino acids. By electrophoresis mobility shift assay, we showed that the glutathione S-transferase-mERR alpha 1 fusion protein produced in a bacterial system bound to the human ERR alpha 1 DNA-binding element. Mouse uterine nuclear extract also interacted with this DNA element and produced three complexes in the mobility shift assay, one of which was supershifted by the hERR alpha 1 antiserum. A 2.2 kbp transcript was detected by Northern analysis in all adult mouse tissues tested; however, large variations in the amount of ERR alpha 1 mRNA were found among them. Multiple immunoreactive forms of mouse ERR alpha 1 were detected by Western analysis in non-reproductive tissues, whereas a major 53 kDa protein was found in reproductive tissues such as uterus, cervix and vagina. Diethylstilbestrol (DES) stimulated the expression of ERR alpha 1 mRNA in the uterus of 19-day-old mouse. We showed that DES and estradiol, but not progesterone or dexamethasone, enhanced the level of immunoreactive ERR alpha 1 in the mouse uterus. These results demonstrated that the ERR alpha 1 is an estrogen-responsive gene in the mouse uterus and provides a model system with which to study the biological roles of this nuclear orphan receptor.

Amino Acid Sequence↗
PubMed1997

[Clinical research of nipple-areola preserved mastectomy and one-stage breast reconstruction with rectus abdominis musculocutaneous flaps].

OBJECTIVE: To discuss the method for nipple-areola preserved mastectomy with one-stage breast reconstruction in cancer surgery. METHODS: Because of the merits of sufficient blood supply and plasticity of rectus abdominis musculocutaneous flap, we used one-stage breast reconstruction after modified radical mastectomy. The incision line was covered and the nipple-areola was preserved. The reconstructed breast was naturally in contour. RESULTS: 21 cases were treated from 1990 to 1995, and 18 of them received horizontal-rhombus shaped rectus abdominis musculocutaneous flaps and 3 longitudinal-rhombus flaps for breast reconstruction. Nipple-areola was preserved in 16 cases. Objective evaluation after operation showed that the excellent and satisfied rate reached to 90.5%; and subjective evaluation showed that the excellent and satisfied rate reached to 95.2%. Thirteen cases have been followed up for 3 years, and 9 for 5 years. Three-year survival rate was 100% (13/13), and 5-year 88.9% (8/9). CONCLUSION: The method is recommendable for the treatment of stage I-II breast cancer.

Adenocarcinoma↗
PubMed1996

Developmental change of megakaryocyte maturation and DNA ploidy in human fetus.

Megakaryocytes in fetal livers obtained from 30 water-balloon aborted normal fetuses of 3 to 6 months' gestation, in the bone marrow from the same 30 fetuses, and another 9 fetuses of 7 to 8 months' gestation and in the normal bone marrow of adults were analyzed by immunocytochemical staining for size and maturation stage distribution and by flow cytometry for ploidy distribution simultaneously. In human fetuses, megakaryocytes showed a shift during ontogenesis from smaller towards larger size and from less mature towards a more mature stage with advancement of gestation. This was accompanied by a significant progressive shift to higher ploidy. However, the proportions (78.64%) of hypoploidy (< or = 8N) megakaryocytes in bone marrow of 7-8 months' gestation fetuses was still much higher than that (33.32%) in human adults (p < 0.05), with the proportion of hyperploidy (> or = 16N) megakaryocytes lower than that (67.86%) in human adults. This result indicated that megakaryocyte polyploidization may be retarded or inhibited during development.

Adult↗
PubMed1996

[Comparative study on assessment of tubal patency among tubal insufflation, hydrotubation, hysterosalpingography and chromotubation under laparoscopy].

OBJECTIVES: To compare the diagnostic value of tubal insufflation, hydrotubation, hysterosalpingography (HSG) and chromotubation under laparoscopy for tubal patency assessment. METHODS: Among 258 women who underwent chromofubation during laparoscopy procedures for infertility assessment in our hospital, tubal insufflation were performed in 42 cases, hydrotubation in 70, HSG in 63, both insufflation and hydrotubation in 20, insufflation and HSG in 11, and hydrotubation and HSG in 22. The accuracy of each method was compared with that of chromotubation under laparoscopy. RESULTS: The accuracy rates of hydrotubation (87.1%) and HSG (73.0%) were significantly higher than that of insufflation (50.0%) (P < 0.01, P < 0.05 respectively). Similar results were shown when 2 different procedures in the same patient were compared with laparoscopy. CONCLUSIONS: Tubal insufflation has no longer its place in tubal patency assessment due to its grossly inaccuracy; Both hydrotubation and HSG can be used as screening methods. Laparoscopy is the most accurate procedure in assessing tubal patency, as well as in searching pelvic abnormalities.

Adult↗