Biomedical subjects

G Zou

Publications and source records attributed to G Zou.

At least 19 recordsLinked to original sources

PubMed2001

Excellent therapeutic efficacy and minimal late neurotoxicity in children treated with 18 grays of cranial radiation therapy for high-risk acute lymphoblastic leukemia: a 7-year follow-up study of the Dana-Farber Cancer Institute Consortium Protocol 87-01.

BACKGROUND: In the current study, the authors evaluated late neuropsychologic effects 7 years after diagnosis and the long-term survival in a cohort of patients treated for high-risk childhood acute lymphoblastic leukemia (ALL) with cranial radiation therapy. Efficacy and toxicity were evaluated in relation to patient age at diagnosis (age < or > or = 36 months). METHODS: Two hundred and one patients treated for high-risk ALL on the Dana-Farber Cancer Institute Consortium Protocol 87-01 were included, 147 of whom were in continuous complete disease remission and were eligible for cognitive testing. Sixty-one patients consented to undergo testing. All patients received 18 grays (Gy) of cranial radiation as a component of central nervous system treatment. RESULTS: For all 201 patients, the 5-year overall survival (% +/- the standard error) was 82% +/- 2 and the 5-year event-free survival (% +/- the standard error) was 75% +/- 3. Only two patients developed a central nervous system recurrence. Intelligence quotient (IQ) and memory were at the expected mean for age, but performance on a complex figure drawing task was found to be reduced. Children who were age < 36 months at the time of diagnosis were found to have an IQ in the average range, but showed verbal deficits. CONCLUSIONS: The results of the current study demonstrate excellent efficacy of therapy and relatively limited late neurotoxicity on a childhood ALL therapy protocol in which all evaluated patients had received 18 Gy of cranial radiation. Efficacious therapy that includes cranial radiation does not appear to necessarily incur a heightened risk for significant cognitive impairment.

Adolescent↗

PubMed2001

[Summarization of studies on Chinese marine medicinal animal Syngnthus acus].

Syngnthus acus L. is a kind of very important traditional Chinese-medicine from sea. It has plentiful amino acid, protein, trace element, poly-carbon non-saturation fat acid, etc. Syngnthus acus has sexual-hormones-like, anti-cancer and resisting fatigue effects; It can resist fatigue. It can also improve organism immunity and enhance the systolic strength of heart muscle. It can be widely used in many fields such as food field, medical field and aquatic products industry. Its classification, resources, chemical composition and its medical value have been summarized in this article.

Amino Acids↗

PubMed2000

Similar outcome of elderly patients in intergroup trial 0096: Cisplatin, etoposide, and thoracic radiotherapy administered once or twice daily in limited stage small cell lung carcinoma.

BACKGROUND: Elderly patients comprise a significant portion of patients with limited stage small cell lung carcinoma. However, the prognostic importance of age has been controversial, and concern for toxicity often hinders enthusiasm for offering full dose therapy. METHODS: In this retrospective analysis of Intergroup Trial 0096, the authors compared the outcome of patients 70 years or older to those younger than 70 years. Patients received cisplatin 60 mg/m(2), Day 1 and etoposide 120 mg/m(2), Days 1-3 for 4 cycles and either once or twice daily concurrent thoracic radiotherapy to 45 grays. RESULTS: Of 381 patients, 50 (13%) were age 70 years or older. The elderly group did not differ significantly from those younger than 70 years with respect to gender distribution, performance status, or weight loss. Severe hematologic toxicity (Grade 4-5: 61% vs. 84%; P < 0.01) and fatal toxicity (1% vs. 10%; P = 0.01) occurred more often among older patients. There were no differences in the frequency of nonhematologic toxicities. Response rate (88% vs. 80%; P = 0.11), event free survival rate (5 year, 19% vs. 16%; P = 0.18), time to local failure, and duration of response did not differ between groups. Overall survival rates (5 year, 22% vs. 16%; P = 0.05) favored those younger than 70 years. Much of the difference in overall survival rates between age groups occurred within the first 6 months on study. CONCLUSIONS: Elderly patients had similar response and survival rates compared with those younger than 70 years. However, toxicity, particularly hematologic, was greater among the elderly. Selected older patients, such as those with a good performance status, should be considered for optimum treatment approaches.

Age Factors↗

PubMed2000

Immunoglobulin heavy-chain consensus probes for real-time PCR quantification of residual disease in acute lymphoblastic leukemia.

Tumor-related immunoglobulin heavy-chain (IgH) rearrangements are markers for polymerase chain reaction (PCR) detection of minimal residual disease (MRD) in B-cell malignancies. Nested PCR with patient IgH allele-specific oligonucleotide primers can detect 1 tumor cell in 10(4) to 10(6) normal cells. In childhood acute lymphoblastic leukemia (ALL), persistence of PCR-detectable disease is associated with increased risk of relapse. The clinical significance of qualitative PCR data can be limited, however, because patients can harbor detectable MRD for prolonged periods without relapse. Recent studies indicate that a quantitative rise in tumor burden identifies patients who are at high risk for relapse. Therefore, an efficient and reliable PCR method for MRD quantification is needed for ALL patients. We have developed a real-time PCR method to quantify MRD with IgH V(H) gene family consensus fluorogenically labeled probes. With this method, a small number of probes can be used to quantify MRD in a large number of different patients. The assay was found to be both accurate and reproducible over a wide range and capable of detecting approximately 1 tumor cell in 5 x 10(4) normal cells. We demonstrate that this methodology can discriminate between patients with persistence of MRD who relapse and those who do not. This technique is generally applicable to B-cell malignancies and is currently being used to quantify MRD in a number of prospective clinical studies at our institution. (Blood. 2000;95:2651-2658)

Base Sequence↗

PubMed2000

Biased Brownian dynamics for rate constant calculation.

An enhanced sampling method-biased Brownian dynamics-is developed for the calculation of diffusion-limited biomolecular association reaction rates with high energy or entropy barriers. Biased Brownian dynamics introduces a biasing force in addition to the electrostatic force between the reactants, and it associates a probability weight with each trajectory. A simulation loses weight when movement is along the biasing force and gains weight when movement is against the biasing force. The sampling of trajectories is then biased, but the sampling is unbiased when the trajectory outcomes are multiplied by their weights. With a suitable choice of the biasing force, more reacted trajectories are sampled. As a consequence, the variance of the estimate is reduced. In our test case, biased Brownian dynamics gives a sevenfold improvement in central processing unit (CPU) time with the choice of a simple centripetal biasing force.

Biochemistry↗

PubMed1999

Magnetite Nanoparticles Prepared by Precipitation from Partially Reduced Ferric Chloride Aqueous Solutions.

Spherical magnetite particles with mean diameter of about 10 nm or less were prepared by means of a reduction-precipitation method with ferric chloride as starting material, which was partially reduced to ferrous salts by Na2SO3 before alkalinizing with ammonia. It was found that the nature of the product depends strongly on the initial ratio R0 = [Fe3+]0/[SO2-3]0. The most appropriate ratio was 3 as proved by X-ray diffraction analysis on the samples although the initial concentration of ferric chloride can be different. Particle diameter increased from ca. 3 to ca. 11 nm with an increase of the concentration of aqueous ferric chloride from 0.075 to 0.45 mol dm-3. The advantage of this method lies in the formation of a red intermediate during the reduction process, which enables us to prevent the reoxidation of the ferrous ions by adding precipitation agents at the end of the reduction reaction without the protection of nitrogen or argon. Copyright 1999 Academic Press.

Journal Article↗

PubMed1999

[The efficacy of p16, p53 and p21 genes on the proliferation of lung cancer cells in vitro].

OBJECTIVE: Whether the p16, p21 and p53 genes inhibit the proliferation of lung cancer cells after transfecting the genes alone or jointly was examined. METHODS: The p16, p21 and p53 genes mediated by Stearylamine/DOPE (SA liposome) were introduced alone and jointly into the non-small cell lung cancer (NSCLC) cell line A549 and small cell lung cancer (SCLC) SH77. The effect of the genes on the growth of the cells was detected by MTT method at day 1, 3, 5 after gene transfection. RESULTS: The p16, p53 and p21 genes alone mediated by SA liposome can inhibit obviously the growth of NSCLC cell line A549 cells, while the genes were slightly effective on SCLC cell line SH77 cells at day 1, 3, 5 after transfecting the genes. But co-transfecting p16 and p21 or p16 and p53 can enhance the inhibiting effect on both A549 and SH77 cells significantly. CONCLUSIONS: The tumor suppressor genes p16, p53 genes and CDK inhibitor p21 gene may be candidate for gene replacement therapy of NSCLC. Co-transfecting p16 gene and p53 gene may be a better choice.

Carcinoma, Non-Small-Cell Lung↗

PubMed1998

[Separation and determination of naproxen by reversed-phase high performance liquid chromatography].

A reversed-phase HPLC method has been developed for the separation and determination of naproxen and its bromo-substituted compound. These compounds were separated on a Shim-pack CLC ODS column (5 microns, 250 mm x 4.6 mm i.d.) by using a methanol-water (80/20, V/V) solution containing 50 mmol/L lactic acid and adjusted to pH 2.5 with perchloric acid as mobile phase, with flow rate of 0.8 mL/min and UV detection at 271 nm. Benzoic acid was selected as an internal standard. At the concentration range of 5-100 mg/L, the linear internal standard working curves with r > 0.9995 were obtained. The accuracy of this method for naproxen and its bromo-substituted compound were 99.83%-102.07% and 99.00%-100.83%, and RSD were < 2.58% and < 3.64% respectively.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1997

Synthesis of Uniform Ferric Oxide Particles from Deionized Colloids

A modified method was employed to prepare monodispersed colloidal particles of ferric (hydrous) oxide. The method contains three steps: (i) preparation of uniform nuclei of ferric hydrous oxide via a so-called instantaneous nucleation method; (ii) purification of the nuclei suspension via dialysis; (iii) aging of the purified nuclei suspension in a reflux reactor at certain pH. Cubic and pseudocubic alpha-Fe2O3 monodisperse particles which are much smaller than the cubic alpha-Fe2O3 particles obtained from the same reactant through a usual method were produced by aging needle like nuclei at a lower pH. A close-packed three-dimensional QDs (quantum dots) superlattice structure 40 nm in edge length with cubic geometry was formed by self-aggregation between spherical amorphous ferric hydrous oxide nuclei 3-5 nm in diameter. The growth processes of the two kind particles were also illustrated. This study showed an approach to prepare smaller particles from aqueous metal salt solutions in relatively higher concentration, and ordered QDs superlattice structure by controlled self-aggregation of QDs in hydrosol.

Journal Article↗

PubMed1997

A comparative study on morphology and immunohistochemistry of rhabdomyosarcoma and embryonal skeletal muscles.

OBJECTIVE: To investigate the histologic and histogenetic relationship between various types of rhabdomyosarcomas (RMS) and embryonal skeletal muscle (ESM) for further understanding of the histogenesis, classification and pattern of differentiation of RMS. METHODS: Fifty cases of variant types of RMS and 20 cases of ESM at different gestational ages were available. All specimens were stained with HE, PAS, Van Gieson, Masson, phosphotungstic acid hematoxilin and with antibodies for the demonstration of vimentin, desmin, HHF-35 and myoglobin by ABC method. RESULTS: The results showed that the order of positive expression and the intensity of positive reaction of the different immunohistochemical staining were consistent with the degree of differentiation of the tumor and the development of the ESM. It is obvious that each type of RMS is composed of tumor cells in different degree of differentiation and is derived from primitive mesodermal cells which are capable of potential differentiation towards mature skeletal muscles. CONCLUSIONS: Based on the results of this study, an ideal histologic classification of RMS should reflect not only the cell morphology and histologic structures but also the degree of differentiation of the tumor cells.

Adolescent↗

PubMed1997

[The experimental study of Pseudomonas contamination in soft drinks].

Bymeans of this study, we have found out about the situation of Pseudomons contamination in the soft drinks which are manufactured and sold at the area of Nanchang City. In the course of this study, we examined total 416 specimens, in which we found that 69 specimens were positive reaction. The positive rate made up 16.59% of the total specimens. From these 69 positive specimens we separate isolated andidentified the following Pseudomonas 111 strains including 16 different species: P. aeruginosa, 9; P. fluorescens biovars; 11; P. putida biovars, 14; P. syringae pathovars, 5; P. mendocina, 5; P. alcaligenes, 23; P. pseudoalcaligenes, 10; P. cepacia, 17; P. solanacearum, 1; P. testosteroni, 1; P. delafieldii, 3; P. facilis, 6; P. flava 1; P. psenudoflava, 2; P. palleronii, 1; and a new species of Pseudomonas--P. halosensibilis. The achievement of this study will provide scientific basis for working out the standards of food safety control and inspection, raising the level of food hygieneinspection, and directing the drinks menufacturers and selling units to strengthen the food safety control and inspection.

Carbonated Beverages↗

PubMed1995

Nearest-neighbor distribution of interacting biological entities.

In this paper, spatial patterns exhibited in many biological systems are studied, based on the principle of maximum entropy. A general mathematical expression of the nearest-neighbor distribution is derived for a class of interacting biological organisms--structures range from cells in a tissue to trees in a forest.

Animals↗

PubMed1995

Visualization of dynamic simulations of muscle thin filaments.

Following a novel computational formalism, the thin filament of muscle can be modeled by a computational machine containing a large number of finite automata that have one-to-one correspondence with the constituent protein molecules. Computer graphics can be used to visualize the correspondence between the states of finite automata and the configurations of protein molecules according to the structural data. The dynamic simulation of the muscle filament that corresponds to the concurrent state transitions of finite automata can be represented as a sequence of video images. The kinetic and structural knowledge of individual protein molecules is, therefore, integrated into a coherent and functional system. This type of computation and visualization can also be useful for the investigation of molecular structure, function, and interaction in various complex biological systems.

Actin Cytoskeleton↗

PubMed1994

A cellular automaton model for the regulatory behavior of muscle thin filaments.

Regulation of skeletal muscle contraction is achieved through the interaction of six different proteins: actin, myosin, tropomyosin, and troponins C, I, and T. Many experiments have been performed on the interactions of these proteins, but comparatively less effort has been spent on attempts to integrate the results into a coherent description of the system as a whole. In this paper, we present a new way of approaching the integration problem by using a cellular automaton. We assign rate constants for state changes within each constituent molecule of the muscle thin filament as functions of the states of its neighboring molecules. The automaton shows how the interactions among constituent molecules give rise to the overall regulatory behavior of thin filaments as observed in vitro and is extendable to in vivo measurements. The model is used to predict myosin binding and ATPase activity, and the result is compared with various experimental data. Two important aspects of regulation are revealed by the requirement that the model fit the experimental data: (1) strong interactions must exist between two successively bound myosin heads, and (2) the cooperative binding of calcium to the thin filament can be attributed in a simple way to the interaction between neighboring troponin-tropomyosin units.

Actin Cytoskeleton↗

PubMed1994

[A new species of Pseudomonas].

A strain No. 9191 isolated from fruit juice mineral drink is gram-negative short-rod. It differs from reported species of Pseudomonas in morphological, physiological and biochemical characteristics. Main characteristics of No. 9191 are single polar flagelled, oxidase and catalase positive, no acid from glucose but producing alkali, nitrate reduced to nitrite, inability to hydrolize gelatin and starch, arginine dihydrolase absent, no growth in presence of 0.85% NaCl. The G+C mol% of DNA is 65.15. It is named Pseudomonas halosensibilis Zou & Cai nov. sp. by the sensibility property for salt.

Beverages↗

PubMed1991

Sulpiride attenuates ranatensin-M-induced antinociception.

Intracerebroventricular (icv) administration of ranatensin-M (RM), a bombesin-like peptide isolated from the skin of Chinese frog Rana margaratae, produced a dose-dependent prolongation in the hot-plate latency in mice. Naloxone 1, 2, or 10 mg.kg-1 ip failed to antagonize the effects of RM. However, RM-induced antinociception was attenuated by pretreatment with sulpiride (Sul, 100 mg.kg-1, ip), a selective DA2 receptor blocker. Sul (100 mg.kg-1, ip) did not affect hot-plate latencies when administered alone. Sch 23390 (0.2 mg.kg-1, ip), a selective DA1 receptor blocker, did not significantly affect RM-induced antinociception. The results suggest that RM-induced antinociception may be mediated by dopamine neurotransmission within the CNS and that it is mainly the D2 receptor which was involved in this effects.

Amino Acid Sequence↗

PubMed1990

Isolation, chemical and biological characterization of margaratensin, a neurotensin-related peptide from the skin of Rana margaratae.

A new neurotensin (NT)-related peptide, margaratensin, was obtained by Sep-Pak C18 and RP-HPLC from methanol extracts of the skin of Chinese frog Rana margaratae. The structure of the peptide has been determined to be Asp-Lys-Arg-Pro-Tyr-Ile-Leu-His-Glu, which is found to be homologous to the COOH-terminal sequence of NT, but has an extra His-Glu at the COOH-terminus. The synthetic preparation was shown to be indistinguishable from the native peptide during HPLC, amino acid analysis and bioassay. Margaratensin exhibited a hypotensive effect in the rat but the response was weaker than NT. The peptide could induce a potent and reproducible contractile activity on GPI which was different from xenopsin, another NT-related peptide from amphibian skin.

Amino Acid Sequence↗

PubMed1990

Synthesis and biological activity of a new frog skin peptide, ranamargarin.

A new frog skin peptide, ranamargarin depicted as H-Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH2' was synthesized by the conventional method. Comparisons of chemical and biological properties of both the synthetic and natural ranamargarins indicated that they were identical, so the chemical structure of ranamargarin was confirmed. Preliminary pharmacological study showed that ranamargarin was highly selective towards the SP-P subtype receptor.

Amino Acid Sequence↗