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Biomedical subjects

Q Sun

Publications and source records attributed to Q Sun.

At least 55 records · Page 3Linked to original sources

Rapid fabrication of three-dimensional porous films with biomimetic patterns by natural evaporation of amphiphilic polyacetylene solutions under ambient conditions.

A simple process for fast fabrication of thin films with biomimetic morphological structures from a group of linear homopolymers is developed. Natural evaporation of tetrahydrofuran, chloroform, and hexane-dichloromethane solutions of poly(phenylacetylene)s that contain amino acid and ethylene glycol moieties under ambient conditions instantly produces three-dimensional porous films with structural patterns reminiscent of honeycombs and radiolarian shells. Morphological analysis by optical and electronic microscopy suggests that vesicles of the amphiphilic polymers serve as building blocks in the self-organization to the biomimetic structures.

Acetylene↗

Predictive value of microalbuminuria in medical ICU patients: results of a pilot study.

STUDY OBJECTIVES: To evaluate the predictive value of microalbuminuria in the development of acute respiratory failure (ARF) and multiple organ failure (MOF) in ICU patients. DESIGN: Prospective, observational study. SETTING: A 31-bed, mixed medicosurgical ICU in a university hospital. PATIENTS: All adult medical patients admitted to the ICU over a 2-month period, except those receiving nephrotoxic drugs, or those with urologic trauma resulting in frank hematuria or urinary infection, or with existing chronic renal disease (serum creatinine level > or 2.0 mg/dL). INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Urinary samples for microalbumin measurement were collected at hospital admission and at 8, 24, 48, 72, 96, and 120 h after hospital admission. The severity of illness was assessed by the APACHE (acute physiology and chronic health evaluation) II score calculated on the first ICU day, and the degree of organ dysfunction was assessed using the sequential organ failure assessment (SOFA) score. Acute respiratory failure (ARF) was defined as a SOFA respiratory score > or = 3. Patients were separated into two groups according to the trend in microalbuminuria levels over the first 48 h: patients in group 1 had increasing microalbuminuria levels, and patients in group 2 had decreasing microalbuminuria levels. Group 1 included 14 patients in whom microalbuminuria levels increased from 5.2 +/- 2.0 to 19.0 +/- 3.0 mg/dL. Group 2 included 26 patients in whom microalbuminuria levels decreased from 16.4 +/- 4.0 to 7.8 +/- 3.0 mg/dL. The hospital mortality rate was 43% in group 1 and 15% in group 2 (p < 0.05). The APACHE II score and the SOFA score were higher in group 1 than in group 2. The negative predictive value of increasing microalbuminuria was 100% for the development of ARF and 96% for MOF; the positive predictive value of increasing microalbuminuria was 57% for the development of ARF and 50% for MOF. CONCLUSIONS: Accurate identification of patients destined for ARF and MOF development may enable therapeutic strategies to be applied to limit the disease process. Trend analysis of urinary albumin excretion over the first 48 h of an ICU admission may provide a useful means of identifying such patients. Additional studies need to be performed in larger, mixed patient populations to confirm these findings.

APACHE↗

[Establishment of suc2 signal sequence trap system].

The secretion of proteins depends on the signal peptide located to the N-terminal of the protein precursor. We established a genetic system in yeast to screen cDNA library for the signal peptide encoding sequences. To do it, we mutated genomic suc2 gene (encoding yeast invertase) of EGY48 by one-step gene disruption method, and got yeast cell lines without invertase expression (EGY48-delta suc). To get vector for library screening, we inserted suc2 gene encoding mature peptide of invertase downstream to yeast promoter P-ADH1, and multiple cloning sites for insertion of library is between suc2 and P-ADH1. EGY48-delta suc transformed with the vector can grow on the medium with glucose as carbon source, but not on the medium with raffinose. Signal peptide of suc2 and alpha chain of human interleukin-2 was fused in frame to suc2 gene, then the two resulting vectors were transformed into EGY48-delta suc, all the transformants can grow in the medium with either raffinose or glucose as carbon source. Hence, the system established here can discern cDNA encoding signal peptide from the one not encoding signal peptide.

Amino Acid Sequence↗

[Evaluation on comprehensive benefits of different regulation models of agroforestry ecosystem in snail river beach].

The economic, ecological, social and comprehensive benefits of different regulation models of agroforestry ecosystem in Nangeng river beach were evaluated by AHP. The results showed that agroforestry ecosystem was significantly superior to reed(Phragmites communis) system. Different regulation models of agroforestry ecosystem had different benefits. The sheet-thinning model had the highest economic, social, and comprehensive benefits, and it was the optimal regulation model. For all thinning models, the key approach to further raise benefits was to choose some intercrop variations, which had a high economic value, especially a high ratio of output to input. For no-thinning model, keeping on intercropping was the effective measure to raise the social and comprehensive benefits.

Ecosystem↗

[Eyelid reconstruction with a reversal flow axial preauricular island flap based on the supraorbital artery].

OBJECTIVE: In order to find an ideal flap to reconstruct the eyelid defect, we have explored the possibilities to reconstruct eyelid with a reversal flow axial preauricular island flap based on the supraorbital artery. METHODS: According to Chen's theory on "reversal flow axial flap", we designed and applied the reversal flow axial preauricular island flap based on the supraorbital artery, which could nourish the flap by anastomotic branches between the supraorbital artery and the frontal branch of the superficial temporal artery. RESULTS: We have successfully reconstructed 7 cases of eyelid defect with this method since 1997. The size of the flaps ranged from 4.0 cm x 2.4 cm to 2.0 cm x 1.8 cm and good result were revealed with 1-2 years follow up. CONCLUSIONS: The flap has a stable and reliable blood supplying. It is an ideal flap to reconstruct the eyelid defect for texture and color similarity of the eyelid and preauricular skin.

Adolescent↗

Confirmation of susceptibility gene loci on chromosome 1 in northern China Han families with type 2 diabetes.

OBJECTIVE: To confirm previous effort to identify type 2 diabetes susceptibility genes in a Northern Chinese population by conducting a new genome scan with both an increased number of type 2 diabetes families and a new set of microsatellite markers within the previously localized regions. METHODS: A genome scan method was applied. After multiplexed PCR, electrophoreses, genescan and genotyping analysis, we obtained size information for all loci, and then a further study was done by both parametric and non-parametric linkage analysis to investigate the P values and Z values of these loci. RESULTS: We surveyed 34 microsatellite markers which distributed within 5 regions along chromosome 1, and a total of 12,000 genotypes were screened. Evidence of linkage with diabetes was identified for 8 of the 34 loci. All P values of the 8 loci were lower than 0.05, and the highest Z value was 2.17. A very interesting finding is that all 5 markers at the p- terminal 1p36.3-1p36.23 region, spanning a long range of 16.9 cM, were identified to have a low P value of less than 0.05, which suggests that this region may contain multiple susceptibility genes. Regions 4 and 5 also confirmed the previous findings, and we narrowed these two regions to a 2.7 cM and 2.5 cM regions, respectively. CONCLUSIONS: We further confirmed the results gained in the previous genome-wide scan using an increased number of NIDDM families and a new set of microsatellite markers lying within the initially localized regions. The fact that all 5 loci at the p- terminal region displayed a low P value of less than 0.05 suggests that more than 1 susceptibility gene may reside in this region.

Chromosomes, Human, Pair 1↗

Monoclonal anti-idiotype antibody bearing the internal image of nasopharyngeal carcinoma associated antigen.

OBJECTIVE: To generate and characterize anti-idiotypic monoclonal antibody (Ab2) that bears the internal image of nasopharyngeal carcinoma (NPC) associated antigen. METHODS: Using NPC monoclonal antibody (Ab1) as immunogen, hybridoma cells were obtained by fusion of SP2/0 myeloma cells with immunized murine spleen cells. Positive clones were screened by Sandwich ELISA and a binding inhibition test. To determine whether Ab2 possess the internal image of the original antigen or not, mice were immunized with Ab2. ELISA and the competitive inhibition assay tested anti-anti-idiotypic antibodies (Ab3) in anti-sera. Cell-mediated immunity to tumors induced by Ab2 was investigated by a delayed-type hypersensitivity response and the mouse T-cell proliferation assay. RESULTS: Anti-idiotypic monoclonal antibodies against the monoclonal anti-NPC antibodies FC2 and HNL5 were generated that recognize NPC associated antigens. These Ab2, which were designated 2H4 and 5D3, could inhibit the binding of FC2 or HNL5 to NPC cell lines. Anti-sera from the immunized mice, which contained Ab3, could compete with FC2 or HNL5 for binding with NPC cell by a competitive inhibition assay. Mice immunized with 2H4 or 5D3 coupled with keyhole limpet hemocyanin (KLH), showed a positive and specific delayed-type hypersensitivity (DTH) reaction after stimulation by NPC cells. The mouse T cell proliferative assay indicated that there was a significantly higher proliferative response of the splenocytes in the experimental groups than that in control groups. CONCLUSIONS: Anti-idiotypic antibodies 2H4 and 5D3 are Ab2 beta bearing the internal image of the epitope of NPC associated antigen. Either 2H4 or 5D3 expressing three-dimensional shapes that resemble the structure of natural antigens could induce humoral and cellular immune response.

Animals↗

Therapeutic antitumor response to cervical cancer in mice immunized with U14 vaccines transfected with costimulatory B7 gene.

OBJECTIVE: To investigate the effect of U14 vaccine transfected with the B7 gene in inducing antitumor immune response to murine cervical carcinoma in Chinese 615-strain mice. METHODS: A recombinant retroviral plasmid vector expressing mouse B7-1 gene (pLNSX-mB7) was transfected into 615-strain mouse cervical carcinoma cell line No. 14 (U14) by electroporation to set up a highly-expressed mB7-1 U14 cell clonal strain (B7+ U14). In vivo experiments: (1) B7+ U14 vaccine was primed to protect the 615-strain mice against U14 re-challenge. (2) B7+ U14 vaccine was injected into tumor-bearing mice with different tumor sizes. Lifetimes and tumor sizes were recorded. In vitro cytotoxicity assay: Mice were immunized with B7+ U14 or U14 vaccine and 2 weeks later, spleen cells of those mice were cultured for 2 days. The cytotoxicity of these cells against U14 was detected by 5-diphenyl tetrazolium bromide assay. RESULTS: We obtained several B7-1 high expression clonal U14 lines. In vivo experiment, we did not find tumor growing in 3 of the 6 mice primed by B7+ U14 vaccine during their entire life after re-challenge with U14. The other 3 mice developed tumors and their average survival time was longer than that of the control group (P < 0.01). All 6 mice grew tumors in the control group. When the transplanted tumors became palpable, the mice were randomly divided into 3 groups to be injected with B7+ U14 vaccine. It was effective for tumor-bearing mice only when the tumor diameters were < 3 mm. When the diameters were > or = 3 mm, it was not efficacious to inject B7+ U14 vaccine (P < 0.05). In vitro cytotoxicity assay, cytotoxic T lymphocytes induced by B7+ U14 vaccine had a higher cytotoxicity against U14 than that induced by U14 vaccine (F = 310.8, P < 0.001). CONCLUSIONS: Vaccines of cervical cancer cells transfected with the costimulatory molecule B7 gene can induce antitumor immune protection in host mice against U14 re-challenge. This treatment may cure part of the tumor-bearing mice but be restricted by tumor size. The results suggest that transfecting the B7 gene into cervical cancer as a cell vaccine may be an efficient supplementary method to treat cervical cancer after operation.

Animals↗

[Study on diarrhea disease and Escherichia coli strains harboring HPI pathogenicity island of Yersinia enterolitica in Shandong province].

OBJECTIVE: It was found that some E. coli strains previously identified as entero SLTs-producing and invasive E. coli (ESIEC), harboring HPI pathogenicity island of Yersinia enterolitica. This research was designed to reveal prevalence, susceptible group and clinical features it caused. METHODS: All of the diarrhea patients were from the out-patient units of four hospitals in Shandong province from June to November of 1997. Stool specimen were collected before administration of antibiotics for isolation of enteric bacterial pathogen. Clinical symptoms were recorded at the same time. RESULTS: A total number of 449 enteric pathogenic bacteria strains were detected among stool samples from 671 patients, with isolation rates of Shigella species and diarrheagenic E. coli 25.48% and 15.05% respectively. When irp-2 and ipaB gene fragments were used as DNA probes, 42 of 176 un-identifiable strains were found irp-2(+) and ipaB(-), which were identified as HPI-harboring E. coli. Typical symptoms of the diarrhea caused by HPI-harboring E. coli were described as mild, including abdominal pain, shiver and vapidity. Temperature of the patients was usually normal. Over 6 times of bowel movements per day was frequently observed, of which most were unformed stools with mucous. CONCLUSION: HIP-harboring E. coli was an important diarrheagenic pathogen identified from 671 patients with diarrhea. Shigella was found to be the majority strain.

China↗

Plants, plant pathogens, and microgravity--a deadly trio.

Plants grown in spaceflight conditions are more susceptible to colonization by plant pathogens. The underlying causes for this enhanced susceptibility are not known. Possibly the formation of structural barriers and the activation of plant defense response components are impaired in spaceflight conditions. Either condition would result from altered gene expression of the plant. Because of the tools available, past studies focused on a few physiological responses or biochemical pathways. With recent advances in genomics research, new tools, including microarray technologies, are available to examine the global impact of growth in the spacecraft on the plant's gene expression profile. In ground-based studies, we have developed cDNA subtraction libraries of rice that are enriched for genes induced during pathogen infection and the defense response. Arrays of these genes are being used to dissect plant defense response pathways in a model system involving wild-type rice plants and lesion mimic mutants. The lesion mimic mutants are ideal experimental tools because they erratically develop defense response-like lesions in the absence of pathogens. The gene expression profiles from these ground-based studies will provide the molecular basis for understanding the biochemical and physiological impacts of spaceflight on plant growth, development and disease defense responses. This, in turn, will allow the development of strategies to manage plant disease for life in the space environment.

Brassica napus↗

[Features of breast ultrasound image and its correlation with estradiol and progesterone level in different phases of menstrual cycle in normal women].

OBJECTIVE: To determine the features of the breast ultrasound image and its correlation with estrogen and progestogen level during different phases of menstrual cycle in normal women. METHODS: Breast ultrasound was performed during luteal phase and late follicular phase in 50 women aged 25-45, with normal menstrual cycle and no distinct breast disease. Breast section thickness, ductal width, breast structure and blood flow were measured. Initial time and persistent days of the cyclic breast pain were recorded. Serum estradiol (E2) and progesterone (P) levels were measured by enzyme immunoassay on the day of ultrasound performed. RESULTS: Breast glandular section was thicker (increasing by 7.3%) in luteal phase than that in late follicular phase and breast ductal was wider (increasing by 13%) in late follicular phase than that in luteal phase. However, both of them had no significant difference. Thirty women (60%) experienced cyclic premenstrual mastalgia, lasting 4 days. Twenty four women (48%) had breast structure changes, nineteen (63.3%) of 30 women with cyclic mastalgia, but only 5 (25%) of 20 women without breast pain had breast structure change (chi 2, P < 0.01). Average serum E2 level of women with or without cyclic breast pain in luteal phase were 365.0 pmol/L and 335.3 pmol/L respectively (P > 0.05), serum progesterone level were 73.3 nmol/L and 66.1 nmol/L respectively (P > 0.05). Serum E2 levels of women with or without cyclic breast pain in late follicular phase were 299.9 pmol/L and 385.8 pmol/L respectively (P = 0.05). Average serum E2 levels of women with or without breast structure change in luteal phase were 368.1 pmol/L and 322.7 pmol/L respectively (P < 0.05). Serum P levels were 78.8 nmol/L and 62.2 nmol/L respectively (P = 0.05); Estradiol levels in late follicular phase were 301.9 pmol/L and 364.2 pmol/L respectively (P > 0.05). CONCLUSIONS: Image of breast ultrasound changed following menstrual cycle in normal menstrual women. Breast structure changes is related to breast pain. Breast pain and breast structure changes may be caused by higher E2 and P level in luteal phase and lower E2/P ratio in late follicular phase.

Adult↗

[Effects of 17 beta-estradiol on the release of nitric oxide from HUVEC].

OBJECTIVE: The protective mechanism of 17 beta-estradiol on blood vessels was investigated to provide evidences for clinical use of hormone replacement therapy in postmenopausal women. METHODS: To observe the effects of 17 beta-estradiol (17 beta-E2), testosterone (T), homocysteine (Hcy), 17 beta-E2 combined with T and 17 beta-E2 combined with Hcy on the production of nitric oxide (NO) released from cultured human umbilical endothelial cells (HUVEC) in vitro. RESULTS: Preincubation with 10(-9) mol/L 17 beta-E2 8-48 hours significantly enhanced the release of nitric oxide from HUVEC versus the control, but 10(-9) mol/L T had no effects within 48 hours. Pretreatment with 10(-9)-10(-7) mol/L testosterone for 24 hours had no effects on the release of NO from HUVEC versus the control, but 10(-6), 10(-5) mol/L T significantly reduced the release of NO from HUVEC. HUVEC were treated by 10(-9)-10(-5) mol/L 17 beta-E2 and 10(-9)-10(-5) mol/L T respectively for 24 hours. 10(-9), 10(-8) mol/L T had no effects on the beneficial effect of 17 beta-E2 with regard to the production of NO from HUVEC, while 10(-5) mol/L T greatly attenuated the beneficial effect of 17 beta-E2 with regard to the production of NO from HUVEC. Pretreatment with 10(-4)-10(-3) mol/L Hcy for 24 hours greatly inhibited the release of NO from HUVEC. If treated HUVEC with various concentrations of 17 beta-E2 (10(-9), 10(-7), 10(-5) mol/L) and Hcy for 24 hours simultaneously, 10(-9)-10(-7) mol/L 17 beta-E2 can partly eliminate the effects of Hcy on the released of NO from HUVEC. CONCLUSIONS: T can not enhance the release of NO from HUVECs. The effect of 17 beta-E2 combined with T on the release of NO depends on the concentration of both 17 beta-E2 and T. When 17 beta-E2 and T are in low dose, HUVEC can release more NO. Hcy can inhibit the release of NO from HUVEC, concomitant treatment with a low dose of 17 beta-E2 may eliminate the effects of Hcy on HUVEC.

Cells, Cultured↗

Functional dissection of the dimerization and enzymatic activities of Escherichia coli nitrogen regulator II and their regulation by the PII protein.

The dimeric two-component system transmitter protein NRII (NtrB) of Escherichia coli, product of glnL (ntrB), controls transcription of nitrogen-regulated genes by catalyzing the phosphorylation and dephosphorylation of the transcription factor NRI (NtrC). Previous studies showed that the PII signal transduction protein inhibits the kinase activity of NRII and activates its phosphatase activity. We observed that PII greatly stimulated the NRII phosphatase activity under conditions where the cleavage of ATP was prevented, indicating that the phosphatase activity did not result simply from prevention of the antagonistic NRII kinase activity by PII. Rather, PII was an activator of the phosphatase activity. To study this regulation, we examined the dimerization and enzymatic activities of NRII and various polypeptides derived from NRII, and their regulation by PII. Our results were consistent with the hypothesis that NRII consists of three domains: an N-terminal domain found only in NRII proteins and two domains formed by the conserved transmitter module of NRII, the phosphotransferase/phosphatase/dimerization (central) domain and the kinase domain. All three domains were involved in regulating the kinase and phosphatase activities of NRII. The N-terminal domain was involved in intramolecular signal transduction, and controlled access to the NRII active site for the isolated dimeric central domain added in trans. The central domain was responsible for dimerization and the phosphotransferase and phosphatase activities of NRII, but the latter activity was weak in the isolated domain and was not regulated by PII. The C-terminal kinase domain was responsible for the kinase activity. The PII protein appeared to interact with the isolated transmitter module of NRII, and not with the N-terminal domain as previously thought, since PII dramatically increased the stoichiometry of autophosphorylation of the isolated transmitter module. However, the phosphatase activity of the transmitter module of NRII was low even in the presence of PII, suggesting that the N-terminal domain was necessary for the central domain to assume the conformation necessary for potent phosphatase activity. Also, PII significantly reduced the rate of transphosphorylation of the isolated central domain by the isolated kinase domain, suggesting that PII interacts directly with the kinase domain. We hypothesize that the binding of PII to the kinase domain of NRII results in an altered conformation that is transmitted to the central and N-terminal domains; this causes the central domain to assume the conformation with potent phosphatase activity.

ATP-Binding Cassette Transporters↗

B lymphoblastoid cell lines as efficient APC to elicit CD8+ T cell responses against a cytomegalovirus antigen.

Potent and readily accessible APC are critical for development of immunotherapy protocols to treat viral disease and cancer. We have shown that B lymphoblastoid cell lines (BLCL) that stably express CMV phosphoprotein 65 (BLCLpp65), as a result of retroviral transduction, can be used to generate ex vivo CTL cultures that possess cytotoxicity against CMV and EBV. In this report, we demonstrate that the EBV-specific cytotoxicity in the BLCLpp65-primed culture had a spectrum of EBV-Ag recognition similar to that of the BLCL-primed counterpart, suggesting that retroviral transduction and expression of the CMV Ag would not compromise the Ag-presenting capacity of BLCL. In addition, BLCLpp65 appeared to present multiple natural pp65 epitopes, because pp65-specific CTL, which recognized different CMV clinical isolates, were generated in BLCLpp65-primed cultures from individuals with various HLA backgrounds. Consistent with a polyclonal expansion of virus-specific CTL, T cell lines established from the BLCLpp65-primed CTL cultures expressed different TCR-Vbeta Although most of the virus-specific T cell isolates were CD8+, EBV-specific CD4+ lines were also established from BLCLpp65-primed cultures. Western blot analysis revealed that the CD8+ lines, but not the CD4+ line, expressed granzyme B, consistent with features of classic CTL. Thus, our results suggested that BLCL stably expressing a foreign Ag might be used as a practical APC to elicit CD8+ T cell responses.

Antigen-Presenting Cells↗

Chiral separation by simultaneous use of vancomycin as stationary phase chiral selector and chiral mobile phase additive.

Improved chiral selectivity was observed for numerous compounds when vancomycin was added to the mobile phase on a Chirobiotic-V column. This chiral mobile phase additive (CMPA) is the same chiral selector as that bonded to the stationary phase of this Chirobiotic-V column. A substantial increase in the difference in enthalpy of transfer, deltadeltaH, and in the difference in entropy of transfer, deltadeltaS, for two enantiomers was observed when vancomycin was used as both the mobile phase and the stationary phase chiral selector. The importance of mobile phase composition, analytical column, CMPA concentration was investigated. Also, higher resolution was observed for the separations of acidic compounds when a fluidity enhancing solvent, such as fluoroform, was added into the mobile phase. However, the most commonly used fluidity enhancement solvent, CO2, was ineffective.

Adsorption↗

A phase I-II trial to examine the toxicity of CMV- and EBV-specific cytotoxic T lymphocytes when used for prophylaxis against EBV and CMV disease in recipients of CD34-selected/T cell-depleted stem cell transplants.

Epstein-Barr virus (EBV)-induced lymphoproliferative disease and cytomegalovirus (CMV) infection are major causes of morbidity and mortality in individuals with compromised cellular immunity. Although anti-viral pharmacological agents exist, severe side effects such as myelosuppression often limit the application of these medications. Infusion of ex vivo-expanded, virus-specific cytotoxic T-lymphocytes (CTL) has been proven to be safe and efficacious for the prophylaxis and treatment of EBV and CMV complications. While EBV-specific CTL can be readily and reliably produced with EBV-immortalized B-lymphoblastoid cell lines (BLCL) as stimulators, current protocols for CMV-specific CTL, which use CMV-infected fibroblasts as stimulators, may be associated with alloreactivity and the need for cloning, as well as the potential for exposure to human blood-born infectious agents. Our laboratory has developed a novel system to generate EBV/CMV-bi-specific CTL by co-culturing PBMC with autologous BLCL expressing a CMV protein pp65 (BLCLpp65) (Sun et al., 1999). pp65, an immunodominant CMV antigen, is transduced into BLCL by a recombinant retrovirus MSCVpp65. While low in alloreactivity, BLCLpp65-stimulated CTL are cytolytic to autologous cells infected with EBV or CMV, and this cytotoxicity is mediated by polyclonal, CD8+, MHC Class I-restricted T-cells. Further experiments revealed that retroviral transduction and expression of pp65 do not compromise the capacity of presenting EBV antigens, and T cells stimulated by BLCLpp65 recognize clinical strains of CMV (Sun et al., 2000). These data indicated that BLCLpp65 could substitute for BLCL as antigen presenting cells in adoptive immunotherapy against EBV-LPD, with the benefit of providing protection against CMV reactivation. This protocol is a Phase I/II study to examine the toxicity associated with and the immunologic effects of ex vivo simultaneously expanded EBV- and CMV-specific CTL for prophylaxis against EBV and CMV complications in recipients of CD34 selected/T-cell depleted stem cell transplants (SCT). EBV/CMV-specific CTL will be generated from peripheral blood mononuclear cells (PBMC) of EBV/CMV-seropositive donors in a course of from 21-28 days by weekly stimulation with autologous BLCLpp65. Qualified CTL will be administered to consenting patients at 40, 60, and 80 days post-transpOFF criteria of molecular virology and immunological reconstitution, which include blood levels of pp65 antigen and EBV viral DNA, and virus-specific CTL precursor frequency. Patients will also be tested for replication-competent retrovirus at 3, 6, and 12 month intervals post-transplant to ensure bio-safety.

Adolescent↗

Newly isolated archaerhodopsin from a strain of Chinese halobacteria and its proton pumping behavior.

A strain of extremely salt-loving halobacteria Halobacterium species xz515 from a salt lake in Tibet was isolated. SDS-polyacrylamide gel electrophoresis shows that there is only one protein on claret membrane, which is the same membrane fraction as purple membrane from Halobacterium salinarum, with a molecular weight close to bacteriorhodopsin (br). The purified retinal containing protein from xz515 has an absorption peak at around 550 nm. These facts indicate that it is a br-like protein. The partial sequence determination [H. Wang et al., Chin. Sci. Bull., 45 (2000)] shows that this br-like protein belongs to the archaerhodopsin family. The measurements of light-induced medium pH change in intact cells and cell envelope vesicles of xz515 suggest that this type of archaerhodopsin has a proton pumping function. However, the study about the dynamics of pumped protons across the membrane reveal that the proton release and proton uptake is in reverse order compared to br. The probable reason, attributing to regulating the rate of proton release is discussed.

Archaeal Proteins↗