v-Myb represses the transcription of Ets-2

The v-Myb oncogene causes monoblastic leukemia and transforms only myelomonocytic cells in culture. The v-Myb protein is nuclear and binds to specific DNA sequences. To identify genes regulated by v-Myb, we utilized primary cells transformed by a retrovirus encoding a v-Myb-estrogen receptor (ER) fusion protein. The Ets-2 gene was not expressed in v-Myb-ER transformed cells in the presence of estradiol, but was expressed within 4 h after estradiol withdrawal. The expression of Ets-2 also increased dramatically following phorbol ester-induced differentiation of the v-Myb-transformed BM2 cell line. Conversely, CRYP-alpha, encoding a transmembrane tyrosine phosphatase, was expressed in the presence but not the absence of estradiol in v-Myb-ER transformed cells. CRYP-alpha was downregulated during the phorbol ester-induced differentiation of BM2 cells. Although LIM-3 expression was estradiol-inducible in v-Myb-ER transformed monoblasts, LIM-3 was expressed neither in primary yolk sac cells transformed by unfused v-Myb nor in BM2 cells. We conclude that although v-Myb has been intensively studied as a transcriptional activator, v-Myb can repress biologically relevant genes such as Ets-2, which promotes macrophage differentiation. In addition, we have shown that some genes that are regulated by a v-Myb-ER fusion protein may not be relevant to the biological function of the unfused v-Myb protein.

Genotyping of human cystic echinococcosis in Xinjiang, PR China

The Xinjiang Uygur Autonomous Region, multi-ethnic province in northwestern China, is one of the most important foci of human cystic echinococcosis (CE) in the world. Two Echinococcus granulosus genotypes (G1 and G6) are known to infect the intermediate hosts in this area but, to date, the source of the human infection remains unclear. The current study aimed to genetically analyse 67 hydatid cysts removed from 47 CE patients for which epidemiological, clinical and serological data were also recorded. Mitochondrial cox 1 gene sequencing suggested that the E. granulosus G1 genotype is the major source of infection (45/47 CE patients). Nevertheless, for the first time in China, 2 patients were found with hydatid cysts of the G6 genotype. In addition, 45 E. granulosus gravid tapeworms, isolated from 13 dogs, were genotyped. The majority of adult worms (42/45) exhibited the G1 genotype, whereas 3 adult tapeworms with the G6 genotype were found in one dog, that also harboured E. granulosus tapeworms of the G1 genotype. This sympatric occurrence of G1 and G6 genotypes of E. granulosus, not only in the same area but also in the same definitive host, raises the interesting question of putative genetic recombination between these E. granulosus genotypes.

Human cystic echinococcosis in two Mongolian communities in Hobukesar (China) and Bulgan (Mongolia)

In order to investigate the prevalence of human cystic echinococcosis (CE) in traditional Mongolian communities in western Mongolia and Xinjiang (northwest China), studies were carried out between 1995 and 2000, on two ethnically identical populations in Hobukesar (China) and Bulgan (Mongolia). The prevalence of human hepatic CE in the two communities was significantly different. In Hobukesar, human CE prevalence by ultrasound was 2.7% (49/1844), while in Bulgan it was 0.2% (4/1609) (P<0.001). Dog surveys showed that coproantigen-positive rates or dog necropsy positives were similar in both communities (35.0% in Hobukesar and 35.7% in Bulgan). Comparing possible risk factors, there appeared to be some significant differences between the two communities, which might contribute to the observed difference in CE prevalence. These included: the proportion of herdsman or farmers recorded; the proportions of dog ownership and livestock ownership; and the proportion of families practising home slaughter. The presence of a Russian dog-dosing programme up to the mid-1980s may explain the lower prevalence of human CE in the Bulgan population; no similar programme operated in the China-administered Hobukesar community.

Anaphylaxis after hamster bites--identification of a novel allergen

BACKGROUND

Hamsters are popular household pets and anaphylaxis after their bites have described. However, the putative allergen has not been identified.

OBJECTIVE

This study was conducted to identify the allergen causing dwarf hamster (Phodopus sungoris) bite-induced anaphylaxis.

METHODS

Two children with hamster bite-induced anaphylaxis were enrolled. They both had negative results to skin testing and specific IgE to hamster epithelium. However, they were both allergic to Dermatophagoides pteronyssinus (Der p). Identification of the putative IgE-binding allergens from the hamster saliva was performed using immunoblot analysis.

RESULTS

A specific IgE-binding component at 21 kD in the hamster saliva was identified. ELISA inhibition tests showed partial inhibition with Der p.

CONCLUSIONS

The putative allergen from the hamster saliva causing dwarf hamster-induced anaphylaxis was identified. Possible cross-reactivity with Der p was demonstrated. Further studies will be needed to identify the exact nature and function of this allergen.

GNB3 gene C825T and ACE gene I/D polymorphisms in essential hypertension in a Kazakh genetic isolate

The Kazakh inhabitants living in Barkol pasture of northeast China belong to a genetic isolate characterized by ethnically homogeneous and a communal pastoral lifestyle. To investigate whether the polymorphisms in the G-protein beta-3 subunit (GNB3) gene and angiotensin-converting enzyme (ACE) gene are associated with essential hypertension (EH), we carried out a case-control study of 290 hypertensive subjects and 244 normotensive (NT) controls randomly selected from Kazakh populations of Barkol. A previous medical history of diabetes and hypertension, and body mass index (BMI) was recorded. Plasma glucose, triglyceride, and cholesterol were measured. The insertion/deletion (I/D) polymorphism of the ACE gene and the C825T polymorphism of the GNB3 gene were determined by the polymerase chain reaction (PCR) technique. The distributions of genotypes and alleles for the two polymorphisms did not differ significantly between the case and control populations, and odds ratio of EH related to the ACE gene D allele and GNB3 gene T allele was not significantly different from 1.0. Logistic regression analysis shows the variation at the GNB3 and ACE did not have any statistically significant synergistic effect on blood pressure (BP). Stratification of NT and untreated hypertensives according to I/D polymorphism of ACE gene and C825T polymorphism of GNB3 gene disclosed no significant difference across genotypes with respect to BMI, glucose, triglyceride, cholesterol, systolic and diastolic BP. In conclusion, the polymorphisms in the GNB3 gene and ACE gene, solely or combined, did not confer a significantly increased risk for the development of EH in the Kazakh isolate of northeast China.

[Experimental observation on anaphylaxis induced by Echinococcus infection in Meriones unguiculatus]

OBJECTIVE

To observe the anaphylaxis induced by Echinococcus granulosus or E. multilocularis (E. g. and E. m.) infection in Meriones unguiculatus.

METHODS

56 and 48 gerbils were intraperitoneally inoculated with E. g. protoscoleces and E. m. tissue homogenate. After three months, the anaphylactic responses initiated by intraperitoneal challenge injection with E. g. cystic fluids or partially purified antigen or E. m. metacestode homogenate antigen were observed. IgE antibody and direct eosinophilic leukocyte count (DELC) were detected at pre-postchallenge.

RESULTS

The infection rates for E. g and E. m. in 56 and 48 gerbils were 89.3% and 97.9%, respectively. Among these groups, the lowest rate of anaphylaxis was 62.5%, the highest was 100%. The lowest rate of anaphylactic shock was 12.5%, and the highest 16.7%. After the gerbis were infected with E. g. and E. m., both IgE antibody and DELC increased gradually. At 60 min post challenge, IgE antibody level were significantly decreased, while DELC showed a sharp increase.

CONCLUSION

Anaphylaxis could be induced in gerbils by Echinococcus infection followed by a challenge injection. Different antigens lead to different and degrees among the anaphylactic responses in the gerbils, however, there were no significant differences between E. g. and E. m. infections in gerbils.

[Evaluation of diagnostic value of 18 kDa antigen in alveolar echinococcosis]

AIM

To evaluate the 18 kDa antigen in diagnosis of human alveolar echinococcosis.

METHODS

A total of 214 sera from patients with alveolar echinococcosis (AE, 33), cystic echinococcosis (CE, 69), cysticercosis (30) and healthy controls (82) were examined by Western blotting to detect the antibodies against 18 kDa antigen using both antigens from protoscoleces of E. granulosus (Eg) and E. multilocularis (Em). All the sera were tested simultaneously by ELISA to detect the antibodies against hydatid cystic fluid antigens of sheep as a comparison.

RESULTS

The positive rate by ELISA was 93.9% in AE, 85.5% in CE, 50% in cysticercosis and 6.1% in healthy controls, respectively, suggesting a critical cross-reaction and a certain degree of nonspecific reaction. The serum positive rates by Western blotting with the 18 kDa antigen of Eg and Em were 90.9% and 90.9% in AE, 10.1% and 13% in CE, 13.3% and 16.7% in cysticercosis, respectively. No positive was found in the sera from healthy controls.

CONCLUSION

The 18 kDa antigen may be used in the differential diagnosis of AE from CE.

Classification, follow-up and recurrence of hepatic cystic echinococcosis using ultrasound images

Ultrasound image and morphological structure of hepatic cystic echinococcosis (CE) were analysed in 277 human cases (385 hepatic hydatid cysts). These included 65 CE cases from community surveys carried out between 1995 and 2000 in 3 countries (China, Mongolia and Jordan) and 212 cases from a clinical hospital survey from Xinjiang, China. A new simplified WHO ultrasound classification for human CE was assessed, and considered useful. It is proposed that type, size and number in particular need to be included in the ultrasound classification of hepatic CE. For comparative purposes 6 categories of type were classified in the study as Type 0 to Type 5 (T0-T5): T0, univesicular without pathognomonic signs; T1, univesicular with pathognomonic signs; T2, cysts with sagging or floating laminated membrane; T3, cysts containing daughter cysts; T4, solid mass or mixed cysts; and T5, cysts with partial or full calcifications. This differs from the WHO classification wherein Type T3 cysts (daughter cysts present) are considered a pathological stage to occur in general prior to the sagging or floating membrane (T2) stage. Recurrent hydatid cysts in the liver were also studied based on morphological structures observed directly from surgical intervention. Case follow-up over 1-5 years since endocystectomy in the community surveys indicated 10% (2/10) recurrence of cysts in the residual surgical cavity. Recurrent CE included 2 (2/4) cases after percutaneous treatment.

Identification of a novel membrane-associated protein expressed in neurons of the squid and rodent nervous systems

In a previous communication, we reported the isolation of a novel cDNA clone (pA6) from a library constructed from squid axonal mRNAs. The partial cDNA clone contained a unique open reading frame that encoded 84 amino acids and was complementary to a moderately abundant mRNA approximately 550-600 nucleotides in length [Chun et al., J. Neurosci. Res. 49 (1997) 144-153]. In this report, we identify the pA6 gene product, and characterize its expression in the squid and rodent brain. Results of immunoblot analyses conducted in squid, using a polyclonal antibody raised against a synthetic peptide corresponding to the C-terminus of the putative protein, established the presence of two pA6 immunoreactive proteins of approximately 14 kDa and 26 kDa in size. In contrast, mouse brain contained only a single 26-kDa immunoreactive species. In both the squid and mouse brain, the expression of pA6 appears highly selective, being detected in certain neurons but not in non-neuronal cells, as judged by both in situ hybridization and immunocytochemistry. Findings derived from light microscopic, double-label immunohistofluorescence studies indicate that pA6 protein co-localizes with prohibitin, a mitochondrial marker protein. Consistent with these results, electron microscopy localized pA6 immunoreactivity to several membrane compartments to include the outer membrane of mitochondria, as well as to the smooth endoplasmic reticulum and tubulovesicles in dendrites, axons, and axon terminals of neurons in the rat brain. Taken together, these findings indicate that pA6 is a novel, membrane-associated protein, which is expressed in the distal structural/functional domains of neurons in both the invertebrate and vertebrate nervous systems.

[Study on regulators of the cell cycle in cutaneous squamous cell carcinoma]

In order to investigate the relationship between the regulators of cell cycle and cutaneous squamous cell carcinoma(SCC), we used an immunohistochemical staining technique to examine the expression of cyclin D1, p16 and Rb in the paraffin embedded skin cancer tissues of 30 patients with SCC. The positive percentage of cyclin D1, CDK4, p16 and Rb was 66.7%, 53.3%, 33.3%, and 36.7%, respectively. The overexpression of cyclin D1 and CDK4 could be observed frequently in low grade of differentiated cells, especially in marginal cells of the cancer nest. The results indicate that the aberrant expression of positive and negative regulators of the cell cycle may be involved in the carcinogenesis and evolution of SCC.

[Intermittent-pulse treatment of onychomycosis with orally administered itraconazole]

Fifty-four patients received an intermittent regimen of itraconazole (26 of them were finger onychomycosis and 28 toe onychomycosis) and were followed-up for nine months. The result showed that the clinical cure rate of fingernails was 88.5% and the mycologic cure rate was 96.4%, while the clinical cure rate of toes was 82.1% and the mycologic cure rate was 96.4%. Few adverse events were observed by 7.4%, just like nausea, gastric discomfort etc. It suggests that the pulse administration system is highly effective and has a few side-effects.

The overall pattern of cardiac contraction depends on a spatial gradient of myosin regulatory light chain phosphorylation

Evolution of the human heart has incorporated a variety of successful strategies for motion used throughout the animal kingdom. One such strategy is to add the efficiency of torsion to compression so that blood is wrung, as well as pumped, out of the heart. Models of cardiac torsion have assumed uniform contractile properties of muscle fibers throughout the heart. Here, we show how a spatial gradient of myosin light chain phosphorylation across the heart facilitates torsion by inversely altering tension production and the stretch activation response. To demonstrate the importance of cardiac light chain phosphorylation, we cloned a myosin light chain kinase from a human heart and have identified a gain-in-function mutation in two individuals with cardiac hypertrophy.

Mapping the velocity vector onto the spin vector: two-dimensional velocity-selective spin excitation for MR flow imaging

This article presents a two-dimensional velocity-selective spin excitation (2D-VSP) method that enables quantitative imaging of motion in two directions in a single scan, without the need for image subtraction or combination. It is based on the idea of mapping a 2D velocity vector directly onto the transverse magnetization vector, such that the signal intensity reflects the speed of motion, while the signal phase represents the direction of motion. Experimental demonstration is presented in conjunction with an analysis of the accuracy of this method. VSP methods are often limited by inconsistent static signal suppression under variable shim and RF conditions. By using adiabatic RF pulses in a 2D-VSP composite that possesses time-reversal symmetry, consistent background suppression of 30-fold or higher was demonstrated over experimental conditions of +/-200 Hz off-resonance and 30% RF field variation.

[Studies on separation, purification and chemical structure of polysaccharide from Atractylodes macrocephala]

Separation and purification were done by column chromatographic fractionation; HPLC and 13C-NMR were used to determine the chemical structure of polysaccharide from Atractylodes macrocephala Koidz;, The molecular weight of the polysaccharide was estimated to be 1.36 x 10(5) (PSAM-1) and 1.04 x 10(5) (PSAM-2).

Mixed echo train acquisition displacement encoding with stimulated echoes: an optimized DENSE method for in vivo functional imaging of the human heart

Mixed echo train acquisition displacement encoding with stimulated echoes (meta-DENSE) is a phase-based displacement mapping technique suitable for imaging myocardial function. This method has been optimized for use with patients who have a history of myocardial infarction. The total scan time is 12-14 heartbeats for an in-plane resolution of 2.8 x 2.8 mm2. Myocardial strain is mapped at this resolution with an accuracy of 2% strain in vivo. Compared to standard stimulated echo (STE) methods, both data acquisition speed and resolution are improved with inversion-recovery FID suppression and the meta-DENSE readout scheme. Data processing requires minimal user intervention and provides a rapid quantitative feedback on the MRI scanner for evaluating cardiac function. Published 2001 Wiley-Liss, Inc.

[Treatment of severe hepatitis with artificial liver support system and liver transplantation]

OBJECTIVE

To observe and investigate the efficacy of the hybrid artificial liver support system plus liver transplantation in the treatments of patients with severe viral hepatitis.

METHODS

Eight severe viral hepatitis patients with metaphase and advanced stage liver failure received the artificial liver support using a self-command extracorporeal hybrid artificial liver support system and orthotopic liver transplantation after the artificial support for 3-14 days.

RESULTS

The liver failure of the 8 patients was controlled by the hybrid artificial liver support effectively. All patients were successfully bridged to orthotopic liver transplantation. Four out of the eight patients survived after transplantation. Four patients died of pulmonary infection or hepatorenal syndrome.

CONCLUSIONS

Artificial liver support system combined with liver transplantation can be regarded as an efficient measure for the treatment of metaphase and advanced stage patients of severe viral hepatitis.

[Inhibition of cultured human retinal pigment epithelial cell by tissue-type plasminogen activator]

PURPOSE

To study the inhibition effects of human retinal pigment epithelial (RPE) cells by tissue-type plasminogen activator(tPA).

METHODS

The effects of tPA on human RPE cells proliferation were studied by viable cell counting and methyl thiazolyl tetrazolium (MTT) colorimetric assay. Flow cytometry (FCM) analysis was used to examine RPE cell cycles.

RESULTS

The proliferation of human RPE cells could be inhibited by 0.1-3 micrograms/ml tPA (P < 0.05). The effects of inhibition were depended on the drug density and the action time directly (P < 0.01). 5 micrograms/ml tPA was deadly-toxic to human RPE cells. FCM revealed that the cells in S phase increased 9.8% (P < 0.05) and cells in G2M phase decreased 6.6% (P < 0.05), compared to controls.

CONCLUSION

tPA at a certain dose range and period could inhibit human RPE cells proliferation without deadly-toxicity. The human RPE cells growth could be interfered in S phase by tPA.

Immunodiagnostic differentiation of alveolar and cystic echinococcosis using ELISA test with 18-kDa antigen extracted from Echinococcus protoscoleces

Immunoblotting analysis was carried out using crude extracts of Echinococccus multilocularis and E. granulosus. A total of 214 serum samples were examined for the detection of antibody responses against 18-kDa polypeptides (Eg18 and Em18). Of 44 sera from patients with alveolar echinococcosis (AE) 91% were positive against both Eg18 and Em18, compared with 10% and 13%, respectively, of 70 cystic echinococcosis (CE) samples and 13% and 17% of 29 cysticercosis samples. A relatively purified 18-kDa antigen was extracted from E. granulosus protoscoleces and an 18-kDa-ELISA test which is simple, fast and highly sensitive and specific has been established. A comparative ELISA analysis, using the purified 18-kDa antigen and pooled AE and CE serum, indicated that there are significant differences in antibody levels between AE and CE sera. The maximum ratio for the evaluation of AE to CE was 2.26. The 18-kDa-ELISA was positive for 91% (40/44) and 11% (8/70) of AE and CE sera, respectively, and there was no cross-reactivity with cysticercosis sera or healthy controls. The overall diagnostic values of 18-kDa-ELISA for AE sera were sensitivity 91%, specificity 94%, positive predictive value 83% and negative predictive value 97%. We conclude that (i) the 18-kDa antigenic component may not be species specific but (ii) levels of antibody to the 18-kDa antigen are significantly different between AE and CE sera. Therefore, the 18-kDa antigen can be a reliable serological marker for differentiation of AE from CE.

Alternative splicing switches potassium channel sensitivity to protein phosphorylation

Alternative exon splicing and reversible protein phosphorylation of large conductance calcium-activated potassium (BK) channels represent fundamental control mechanisms for the regulation of cellular excitability. BK channels are encoded by a single gene that undergoes extensive, hormonally regulated exon splicing. In native tissues BK channels display considerable diversity and plasticity in their regulation by cAMP-dependent protein kinase (PKA). Differential regulation of alternatively spliced BK channels by PKA may provide a molecular basis for the diversity and plasticity of BK channel sensitivities to PKA. Here we demonstrate that PKA activates BK channels lacking splice inserts (ZERO) but inhibits channels expressing a 59-amino acid exon at splice site 2 (STREX-1). Channel activation is dependent upon a conserved C-terminal PKA consensus motif (S869), whereas inhibition is mediated via a STREX-1 exon-specific PKA consensus site. Thus, alternative splicing acts as a molecular switch to determine the sensitivity of potassium channels to protein phosphorylation.

Cystic echinococcosis in semi-nomadic pastoral communities in north-west China

In order to determine the prevalence of human cystic echinococcosis (CE) in semi-nomadic traditional pastoralist groups in north-west China, 2 large community studies were undertaken in Altai and Tacheng Prefectures in 1990/91 and 1995/96, respectively. The Kekergash community (Altai) comprised mainly ethnic Kazakhs, whereas the Narenhebuke community (Tacheng) comprised mainly Mongolians. Populations were screened for CE by abdominal ultrasound scan (US) and serological tests. The total prevalence of confirmed human CE was higher in Narenhebuke (2.7%, 49/1844) than in Kekergash (0.9%, 17/1861; P < 0.01). Within each community there was no significant difference of CE prevalence between the Kazakh and Mongolian groups, although Han Chinese exhibited twice the rate of CE (4.9%) in Narenhebuke compared to the dominant Mongolian population. For each community, human CE prevalence increased with age and there was a greater risk associated with the practice of home slaughter of livestock. Dogs were screened for Echinococcus granulosus infection and re-infection levels using a highly specific coproantigen test. The proportion of dogs with positive coproantigen tests was significantly higher in Narenhebuke (36.0%, 50/139) compared to Kekergash (17.8%, 16/90). In Narenhebuke the re-infection levels of dogs, as determined by coproantigen positivity, were higher in the winter quarters (49.4%, 39/79) compared to the summer quarters (18.3%, 11/60; P < 0.01). Furthermore, coproantigen re-test positivity was 25% at 3 months and 29.2% at 7 months. Highest dog coproantigen positivity was obtained over the winter period.

[Expression of estrogen receptor beta mRNA in endometrial carcinoma and its significance]

OBJECTIVE

To investigate the expression of estrogen receptor beta (ER beta) mRNA and its significance in endometrial carcinoma.

METHODS

Thirty-six normal and 45 cancer tissue samples of endometrium were obtained, and the RNA was isolated from the tissues by the acid guanidium thiocyanate-phenol-chloroform extraction method. Reverse-transcription polymerase chain reaction (RT-PCR) was used to amplify the ER beta exon 5 wild type mRNA (ER beta WT) and splicing variant mRNA (ER beta E5SV). Electrophoresis of polymerase chain reaction product was performed and the ratio of ER beta E5SV/ER beta WT was calculated. The sequencing of ER beta E5SV and ER beta WT was carried out by express DNA sequencer.

RESULTS

ER beta E5SV and ER beta WT were both expressed in normal endometrium and endometrial cancer tissues. A region of 139 bp from base pair 812 to 950 (the hormone-binding domain) was found to be deleted in ER beta E5SV sequence as compared to ER beta WT. The quantity of ER beta E5SV was more than that of ER beta WT in every normal endometrium, and was less in every endometrial cancer, the ratio of ER beta E5SV/ER beta WT was 2.47 +/- 0.99 in normal endometrium, and 0.55 +/- 0.12 in endometrial cancer (P < 0.0001). The ratio of ER beta E5SV/ER beta WT decreased with the grade from 1 to 3 (P < 0.01).

CONCLUSION

Overexpression of ER beta WT relative to ER beta E5SV may correlate with the genesis of endometrial carcinoma.