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1.
Public Health ; 212: 102-110, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36306686

ABSTRACT

BACKGROUND: Little is known about the disease burden of chronic obstructive pulmonary disease (COPD) and asthma in southern China. METHOD: We calculated the mortality, disability-adjusted life-years (DALY), years lived with disability (YLD) and years of life lost (YLL) for COPD and asthma in Guangdong province between 2005 and 2015. We examined the significance of trends of mortality, DALY, YLD and YLL rates for COPD and asthma with the Cochran-Armitage trend test. We also analyzed their association with sociodemographic factors by negative binomial models. RESULT: The age-standardized mortality, DALY, YLD and YLL rates of COPD and asthma decreased significantly in Guangdong, except for an increase of 11.3% in the age-standardized YLD rate of COPD between 2005 and 2015 (all P < 0.05). Compared with females, the respective adjusted mortality rate ratio of males was 2.11 for COPD, and 0.74 for asthma. Compared with other regions, the richest region, Pearl River Delta, had the lowest mortality, DALY, YLD and YLL rate ratios (RR) of COPD and asthma (all P < 0.05). COPD and asthma mortality, DALY, YLD and YLL rates increased substantially with age. Specifically, when compared with the 25-49 years age group, the respective adjusted DALY RR of asthma was 1.91, 2.02 and 22.21 for 0-24, 50-74 and ≥75 years age group; the respective adjusted YLD RR was 2.27, 1.33 and 7.17 for 0-24, 50-74 and ≥75 years age group. CONCLUSIONS: Disease burden of COPD and asthma decreased in Guangdong province in southern China between 2005 and 2015; however, a disproportionate burden of COPD and asthma in terms of age, sex and regions was observed. The relatively high disease burden and high rate of impaired public health from the less developed regions highlight the need for focused policy making to address the problem.


Subject(s)
Asthma , Disabled Persons , Pulmonary Disease, Chronic Obstructive , Male , Female , Humans , Aged , Quality-Adjusted Life Years , Cost of Illness , Pulmonary Disease, Chronic Obstructive/epidemiology , Asthma/epidemiology , China/epidemiology
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(4): 474-478, 2022 Apr 06.
Article in Zh | MEDLINE | ID: mdl-35488546

ABSTRACT

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.


Subject(s)
COVID-19 , Contact Tracing , Cohort Studies , Humans , Incidence , Prospective Studies
3.
Zhonghua Zhong Liu Za Zhi ; 41(5): 393-397, 2019 May 23.
Article in Zh | MEDLINE | ID: mdl-31137176

ABSTRACT

Objective: To estimate the incidence, mortality and characteristics of cancer in Pearl River Delta Area of Guangdong Province between 2009-2013. Methods: Based on five population-based cancer registration data from Guangzhou, Shenzhen, Zhongshan, Jiangmen and Sihui spanning from 2009 to 2013, along with those corresponding population data, the incidence and mortality rates were estimated by gender and age groups. Chinese standard population derived from the 2000 Population Census and Segi's standard population were used for age-standardized incidence and mortality rates. Results: Between 2009 and 2013, the crude cancer incidence rate was 262.50/100 000, 274.76/100 000 in male and 249.49/100 000 in female. After adjusting for Chinese and Segi's standard population, the age-standardized incidence rates were 225.63/100 000 and 219.88/100 000, respectively. The crude mortality rate was 175.51/100 000, 222.92/100 000 in male and 127.46/100 000 in female, respectively. After adjusting for Chinese and Segi's standard population, the age-standardized mortality rates were 116.02 /100 000 and 114.31/100 000, respectively. The incidence rates were at low levels in the population less than 40 years old, thereafter went up rapidly with age especially in male, and then reached the peak in the population aged 80 and above. As with incidence, the mortality rates kept at low levels in the population before their 50 s and then rose up steadily with age until peaking in the 85+ age group. The most common cancers were female breast cancer, lung cancer, colorectal cancer, liver cancer and nasopharyngeal cancer with descending incidence rate. Lung cancer, liver cancer, colorectal cancer, female breast cancer and nasopharyngeal cancer were the top five cancer-attributable causes of death. Conclusions: Currently, Pearl River Delta Area were faced with huge cancer burden. Lung cancer, colorectal cancer, nasopharyngeal cancer, female breast cancer and male liver cancer are predominant cancers and more efforts should be made to fight against them.


Subject(s)
Neoplasms/epidemiology , Adult , Aged , Aged, 80 and over , China/epidemiology , Female , Humans , Incidence , Male , Middle Aged , Neoplasms/mortality , Registries
4.
Article in Zh | MEDLINE | ID: mdl-29294516

ABSTRACT

Objective: To investigate the dynamic expression of placenta growth factor (PlGF) in the lungs and its role in paraquat-induced pulmonary fibrosis and to evaluate the effect of ACEI captopril and AT (1) -receptor blocker losartan on paraquat-induced pulmonary fibrosis. Methods: 84 adult healthy female Sprague-Dawley (SD) rats were randomly divided into four groups of different treatments designated as: Control, PQ alone (PQ) , captopril treatment, losartan treatment. Each group was divided into three subgroups of seven animals each. The animals were killed at either 7, 14 or 28 days after PQ administration. The rats in PQ group, treatment group were treated intragastrically (ig) with PQ (40 mg/kg) and the rats in control group were treated with the same dose of saline at the beginning of the experiment. The treatment group received Captopril (60 mg/kg; ig) or Losartan (10 mg/kg; ig) once a day respectively after PQ administration and the other two groups received saline. At the given timepoint, animals were sacrificed and lungs were harvested. A semiquantitative assay of histological examination, hydroxyproline in lung tissues were used to determine the severity of alveolitis and fibrosis. RT-PCR and immunohistochemistry were used to detect the mRNA and protein expression of PlGF. Results: Inflammatory cell infiltration and fibrotic scores were more prominent in the model group, hydroxyproline contents in lung tissue were significantly increased after PQ administration compared to the control group. Captopril, losartan apparently attenuated the degree of lung injury and pulmonary fibrosis. On 7th, 14th days, the levels of alveolitis in the intervention groups were significantly alleviated as compared with the model group (P<0.05) . On 28th days, the levels of pulmonary fibrosis in the intervention groups were significantly alleviated as compared with model group (P<0.05) . The hydroxyproline contents in the intervention groups were significantly decreased as compared with model group (P<0.01) . PlGF mRNA on day 7, 14, 28 (1.28±0.29vs0.10±0.01、0.80±0.07vs0.10±0.01、0.65±0.13vs0.10±0.01) in the PQ group were all upregulated as compared with that of the control group. PlGF mRNA on day 7, 14, 28 in the captopril and Losartan intervention groups were significantly decreased (0.94±0.04、0.71±0.09、0.52±0.24 and 0.80±0.12、0.66±0.11、0.51±0.03) . PlGF positive expression index on day 7, 14, 28 (2.27±0.34 vs0.13±0.01、1.78±0.41 vs0.14±0.03、1.25±0.69 vs0.13±0.01) in the PQ group were all upregulated as compared with that of the control group. PlGF positive expression index on day 7, 14, 28 in the captopril and Losartan treatment groups were significantly decreased (1.53±0.78、1.17±0.79、0.97±0.61 and 1.36±0.63、1.24±0.80、0.83±0.47) . PlGF positive expression index on day 7 in the two intervention groups were significantly decreased, as compared with PQ group (P<0.05) . Conclusion: PlGF may plays an important role in the development of pulmonary fibrosis following paraquat-induced lung injury in rats. Captopril and losartan had an inhibitory effect on paraquat-induced pulmonary fibrosis, and the effect may be due to inhibition of angiotensin II and, in part, be associated with reduction in PlGF.


Subject(s)
Captopril/pharmacology , Losartan/pharmacology , Paraquat/toxicity , Placenta Growth Factor/metabolism , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/drug therapy , Animals , Female , Lung/metabolism , Lung/pathology , Placenta Growth Factor/drug effects , Random Allocation , Rats , Rats, Sprague-Dawley
5.
Public Health ; 129(9): 1211-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25957853

ABSTRACT

OBJECTIVE: To examine the test-retest reliabilities and relative validities of the Chinese version of short International Physical Activity Questionnaire (IPAQ-S-C), the Global Physical Activity Questionnaire (GPAQ-C), and the Total Energy Expenditure Questionnaire (TEEQ-C) in a population-based prospective study, the Taizhou Longitudinal Study (TZLS). STUDY DESIGN: A longitudinal comparative study. METHODS: A total of 205 participants (male: 38.54%) aged 30-70 years completed three questionnaires twice (day one and day nine) and physical activity log (PA-log) over seven consecutive days. The test-retest reliabilities were evaluated using intra-class correlation coefficients (ICCs) and the relative validities were estimated by comparing the data from physical activity questionnaires (PAQs) and PA-log. RESULTS: Good reliabilities were observed between the repeated PAQs. The ICCs ranged from 0.51 to 0.80 for IPAQ-C, 0.67 to 0.85 for GPAQ-C, and 0.74 to 0.94 for TEEQ-C, respectively. Energy expenditure of most PA domains estimated by the three PAQs correlated moderately with the results recorded by PA-log except the walking domain of IPAQ-S-C. The partial correlation coefficients between the PAQs and PA-log ranged from 0.44 to 0.58 for IPAQ-S-C, 0.26 to 0.52 for GPAQ-C, and 0.41 to 0.72 for TEEQ-C, respectively. Bland-Altman plots showed acceptable agreement between the three PAQs and PA-log. CONCLUSION: The three PAQs, especially TEEQ-C, were relatively reliable and valid for assessment of physical activity and could be used in TZLS.


Subject(s)
Motor Activity , Surveys and Questionnaires , Adult , Aged , China , Female , Humans , Longitudinal Studies , Male , Middle Aged , Reproducibility of Results
6.
Science ; 260(5111): 1130-2, 1993 May 21.
Article in English | MEDLINE | ID: mdl-8493557

ABSTRACT

A potent neurotrophic factor that enhances survival of midbrain dopaminergic neurons was purified and cloned. Glial cell line-derived neurotrophic factor (GDNF) is a glycosylated, disulfide-bonded homodimer that is a distantly related member of the transforming growth factor-beta superfamily. In embryonic midbrain cultures, recombinant human GDNF promoted the survival and morphological differentiation of dopaminergic neurons and increased their high-affinity dopamine uptake. These effects were relatively specific; GDNF did not increase total neuron or astrocyte numbers nor did it increase transmitter uptake by gamma-aminobutyric-containing and serotonergic neurons. GDNF may have utility in the treatment of Parkinson's disease, which is marked by progressive degeneration of midbrain dopaminergic neurons.


Subject(s)
Dopamine/biosynthesis , Mesencephalon/drug effects , Nerve Growth Factors , Nerve Tissue Proteins/pharmacology , Neuroglia/metabolism , Neurons/drug effects , Amino Acid Sequence , Animals , Astrocytes/cytology , Astrocytes/drug effects , Base Sequence , Cell Differentiation/drug effects , Cell Line , Cell Survival/drug effects , Cells, Cultured , Cloning, Molecular , Glial Cell Line-Derived Neurotrophic Factor , Humans , Mesencephalon/cytology , Mesencephalon/metabolism , Molecular Sequence Data , Molecular Weight , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/isolation & purification , Neurons/cytology , Neurons/metabolism , Parkinson Disease/drug therapy , Rats
7.
Science ; 246(4933): 1023-5, 1989 Nov 24.
Article in English | MEDLINE | ID: mdl-2587985

ABSTRACT

Ciliary neurotrophic factor (CNTF) is one of a small number of proteins with neurotrophic activities distinct from nerve growth factor (NGF). CNTF has now been purified and cloned and the primary structure of CNTF from rabbit sciatic nerve has been determined. Biologically active CNTF has been transiently expressed from a rabbit complementary DNA clone. CNTF is a neural effector without significant sequence homologies to any previously reported protein.


Subject(s)
Nerve Growth Factors/genetics , Nerve Tissue Proteins/genetics , Amino Acid Sequence , Animals , Cell Line , Ciliary Neurotrophic Factor , Cloning, Molecular , DNA/genetics , Molecular Sequence Data , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/isolation & purification , Rabbits , Recombinant Proteins/biosynthesis , Sciatic Nerve/metabolism , Transfection
8.
Recent Pat Anticancer Drug Discov ; 13(3): 341-347, 2018.
Article in English | MEDLINE | ID: mdl-29512471

ABSTRACT

BACKGROUND: Paclitaxel (PTX) has remarkable anti-tumor activity, but it causes severe toxicities. There is an urgent need to seek an appropriate pharmacokinetic parameter of PTX to improve treatment efficacy and reduce adverse effects. OBJECTIVE: To evaluate the association of pharmacokinetic parameter TC > 0.05 of paclitaxel (PTX) and its therapeutic efficacy and toxicity in patients with solid tumors. METHODS: A total of 295 patients with ovarian cancer, esophageal cancer, breast cancer, and non-small cell lung cancer (NSCLC), who were admitted to the Tumor Hospital of Shantou University Medical College, China, were recruited for this study. Patients received 3 weeks of PTX chemotherapy. The plasma concentrations of PTX were examined using the MyPaclitaxel™ kit. The patients' PTX TC > 0.05 (the time during which PTX plasma concentration exceed 0.05µmol/L) were calculated based on pharmacokinetic analysis. RESULTS: The results showed that: (1) the concentrations of PTX in these 295 patients ranged from 0.0358-0.127 µmol/L; (2) the PTX TC > 0.05 ranged from 14 to 38h with a median time of 27h; (3) among all treatment cycles, there was a statistically significant difference in the PTX TC > 0.05 between CR+PR and SD+PD; (4) with the increasing value of TC > 0.05, level of leukopenia and leukopenic fever increased; (5) high PTX TC > 0.05 led to the occurrence of neutropenia, neutropenic fever, severe anemia, and severe peripheral neurotoxicity. Taken together, our results indicated that the pharmacokinetic parameter PTX TC > 0.05 was an effective measure of treatment efficacy and toxicity in patients with solid tumors. Maintaining PTX TC > 0.05 at 26 to 30h could improve its efficacy and reduce the incidence of leukopenia, neutropenia, anemia, and peripheral neurotoxicity in these patients. CONCLUSION: PTX TC > 0.05 is a key pharmacokinetic parameter of PTX which should be monitored to optimize individual treatment in patients with solid tumors.


Subject(s)
Antineoplastic Agents, Phytogenic/blood , Antineoplastic Agents, Phytogenic/therapeutic use , Neoplasms/blood , Neoplasms/drug therapy , Paclitaxel/blood , Paclitaxel/therapeutic use , Adult , Aged , Antineoplastic Agents, Phytogenic/adverse effects , China/epidemiology , Female , Humans , Leukopenia/blood , Leukopenia/chemically induced , Leukopenia/epidemiology , Male , Middle Aged , Neoplasms/epidemiology , Neutropenia/blood , Neutropenia/chemically induced , Neutropenia/epidemiology , Paclitaxel/adverse effects , Treatment Outcome
9.
Nucleic Acids Res ; 28(17): 3216-23, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10954588

ABSTRACT

Helicobacter pylori is a gram-negative bacterium, which colonizes the gastric mucosa of humans and is implicated in a wide range of gastroduodenal diseases. The genomic sequences of two H.pylori strains, 26695 and J99, have been published recently. About two dozen potential restriction-modification (R-M) systems have been annotated in both genomes, which is far above the average number of R-M systems in other sequenced genomes. Here we describe a functional analysis of the 16 putative Type II R-M systems in the H. pylori J99 genome. To express potentially toxic endonuclease genes, a unique vector was constructed, which features repression and antisense transcription as dual control elements. To determine the methylation activities of putative DNA methyltransferases, we developed polyclonal antibodies able to detect DNA containing N6-methyladenine or N4-methylcytosine. We found that <30% of the potential Type II R-M systems in H.pylori J99 strain were fully functional, displaying both endonuclease and methyltransferase activities. Helicobacter pylori may maintain a variety of functional R-M systems, which are believed to be a primitive bacterial 'immune' system, by alternatively turning on/off a subset of numerous R-M systems.


Subject(s)
Adenine/analogs & derivatives , Cytosine/analogs & derivatives , DNA Modification Methylases/genetics , Deoxyribonucleases, Type II Site-Specific/genetics , Genes, Bacterial/genetics , Genome, Bacterial , Helicobacter pylori/enzymology , Helicobacter pylori/genetics , Adenine/immunology , Adenine/metabolism , Antibodies/immunology , Cloning, Molecular , Computational Biology , Cytosine/immunology , Cytosine/metabolism , DNA Methylation , DNA Modification Methylases/metabolism , Deoxyribonucleases, Type II Site-Specific/metabolism , Genetic Vectors/genetics , Open Reading Frames/genetics
10.
Neurosci Lett ; 183(3): 147-50, 1995 Jan 09.
Article in English | MEDLINE | ID: mdl-7739781

ABSTRACT

Extracellular ATP is shown to induce catecholamine secretion in bovine chromaffin cells. Our data indicate that cells in culture gradually increase their response to ATP, and we have separated freshly isolated cells on a density gradient and found that the lighter cells develop a much stronger response to ATP than do the heavier cells. To see if the ATP sensitivity is physiological, we have perfused intact adrenal glands. ATP induces a greater secretory response from glands than does acetylcholine without causing preferential secretion of norepinephrine or epinephrine. These data show that the response to ATP found in cultured cells is not an artifact of cell culture, and that ATP co-released with catecholamines from the storage vesicles may have a significant physiological role.


Subject(s)
Adenosine Triphosphate/pharmacology , Adrenal Glands/metabolism , Chromaffin System/metabolism , Epinephrine/metabolism , Norepinephrine/metabolism , Adrenal Glands/cytology , Adrenal Glands/drug effects , Animals , Bradykinin/pharmacology , Cattle , Cell Size/physiology , Cells, Cultured , Centrifugation, Density Gradient , Chromaffin System/cytology , Chromaffin System/drug effects , Chromatography, High Pressure Liquid , Dimethylphenylpiperazinium Iodide/pharmacology
11.
Neurosci Lett ; 182(1): 107-11, 1994 Nov 21.
Article in English | MEDLINE | ID: mdl-7891873

ABSTRACT

Fischer 344 rats were unilaterally injected into the medial forebrain bundle with 6-hydroxydopamine (6-OHDA). Apomorphine-induced rotational behavior was used to select animals whose rotation exceeded 300 turns/h, corresponding to greater than 95% dopamine (DA) depletion in the ipsilateral striatum. Four weeks later, glial cell line-derived neurotrophic factor (GDNF) or vehicle was injected intranigrally ipsilateral to the lesion (0.1-100 micrograms). The highest dose of GDNF tested produced a marked decrease in rotational behavior. This dose also produced levels of DA in the ipsilateral substantia nigra (SN) which were not statistically different from the contralateral side. Vehicle-treated animals showed a marked DA depletion in the ipsilateral SN. These results demonstrate neurochemical and behavioral improvements in unilaterally DA-lesioned rats following intranigral administration of GDNF, suggesting that GDNF may develop into a useful therapy for Parkinson's disease.


Subject(s)
Dopamine/metabolism , Mesencephalon/drug effects , Nerve Growth Factors/pharmacology , Neuroglia/metabolism , Neurons/drug effects , Oxidopamine/pharmacology , Animals , Behavior, Animal/drug effects , Cell Line , Dose-Response Relationship, Drug , Injections , Male , Mesencephalon/pathology , Nerve Growth Factors/metabolism , Rats , Rats, Inbred F344 , Rotation , Stereotyped Behavior/drug effects , Substantia Nigra/physiology
12.
Talanta ; 37(9): 941-5, 1990 Sep.
Article in English | MEDLINE | ID: mdl-18965046

ABSTRACT

A versatile method for the determination of Ag is described. It is based on controlled-potential electrolysis with a tantalum cathode in the presence of lactic acid at pH 2-6. An SCE of double-junction type with sodium formate bridge electrolyte is used as the reference electrode. The role of washing after electrolysis is studied and a novel technique suggested. The standard deviation of the determination is 0.13 mg. A preliminary separation is needed only if W is present. The proposed method has been satisfactorily applied to the analysis of a large number of silver alloys with different compositions.

14.
Eur J Surg Oncol ; 38(12): 1156-60, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23017426

ABSTRACT

OBJECTIVES: This study assessed the maximum standard uptake value of positron emission tomography-computed tomography in patients of pulmonary adenocarcinoma with bronchioloalveolar carcinoma features and whether SUVmax correlates with pathological status, lymph node metastasis, and prognosis. METHODS: We retrospectively reviewed 674 patients diagnosed with non-small-cell lung cancer between January 2002 and June 2009. Patients with clinical stage I-II disease underwent a preoperative PET-CT scan followed by anatomic resection. We reviewed the clinical features of 209 patients with an average follow-up of 87 months. RESULTS: We analyzed clinical variables for 40 patients with BAC features and 169 patients without BAC features. Age, sex, location, and number of dissected lymph nodes, carcinoembryonic antigen level, and lymphovascular invasion had no difference between the two groups. Compared with non-BAC patients, patients with BAC features had a lower SUVmax (2.51 ± 2.02 vs 4.98 ± 4.03, p < 0.001), lower ratio of SUVmax (1.10 ± 0.34 vs 1.22 ± 0.27, p = 0.014), better tumor differentiation (p < 0.001), and smaller tumor size (2.30 ± 1.41 vs 2.97 ± 1.71, p < 0.03). The negative prediction rate was 87.08% for N2 and 80.80% for N1 disease. All patients in the BAC group were alive after the operation. The five-year survival rate of patients without BAC features was 71.2%. CONCLUSIONS: Preoperative SUVmax of PET-CT was more accurate at predicting negative N2 than N1 disease. BAC is associated with markedly better prognosis compared with invasive adenocarcinoma and may be cured with surgical resection Aggressive surgical resection is recommended even for patients with false-negative N2 disease.


Subject(s)
Adenocarcinoma, Bronchiolo-Alveolar/diagnostic imaging , Lung Neoplasms/diagnostic imaging , Positron-Emission Tomography , Adenocarcinoma, Bronchiolo-Alveolar/surgery , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Lung Neoplasms/surgery , Male , Middle Aged , Preoperative Period , Prognosis , Reproducibility of Results , Retrospective Studies
16.
Biochemistry ; 19(22): 5135-40, 1980 Oct 28.
Article in English | MEDLINE | ID: mdl-7459326

ABSTRACT

"Soluble protein factor" (SPF) from hog liver stimulates hepatic microsome-associated squalene epoxidase in the presence of phosphatidylglycerol or phosphatidylserine. When SPF and phosphatidylglycerol are preincubated for 30 min at 37 degrees C before addition to the epoxidase system, this stimulation is abolished. On Sephadex chromatography of the protein--phospholipid mixture, both components appear in the void volume, whereas SPF alone is retarded on the column. These results suggest formation of a SPF--phosphatidylglycerol complex. Treatment of the complex with Tween 80 restores the stimulatory effects of SPF on squalene epoxidase. The stimulation of microsomal squalene epoxidase by SPF was abolished by pretreatment of the membrane with low concentrations of deoxycholate or by solubilizing the enzyme with Triton X-100, implying that an intact membrane system is required for SPF sensitivity. SPF has been purified 1200-fold from hog liver.


Subject(s)
Liver Extracts/pharmacology , Microsomes, Liver/enzymology , Oxygenases/metabolism , Phosphatidylglycerols/pharmacology , Phosphatidylserines/pharmacology , Animals , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Liver Extracts/isolation & purification , Octoxynol , Polyethylene Glycols/pharmacology , Polysorbates/pharmacology , Squalene Monooxygenase , Swine
17.
Comp Biochem Physiol B ; 91(3): 505-9, 1988.
Article in English | MEDLINE | ID: mdl-2466603

ABSTRACT

1. Myelin proteolipid proteins (PLPs) from five animal species were compared immunochemically. In direct electroblot, ELISA or immunodot analyses, anti-bovine PLP antiserum reacted similarly with bovine, guinea-pig, human, mouse and rat myelin PLP. In contrast, antiserum to bovine BPS4, a fragment obtained by chemical cleavage of bovine PLP, reacted strongly only with the bovine protein. 2. In comparable competitive assays in which antisera were preincubated with PLP from different species prior to reaction with bovine PLP, only preincubation with bovine PLP removed the antibody effectively; PLP from other species competed poorly. 3. The deduced primary structure of human, mouse and rat PLP from their cDNA indicates sequence identity. However, these sequences differ from bovine PLP at four residues, two of them within the BPS4 region. The results suggest that, while anti-PLP antiserum fails to differentiate heterologous from homologous antigen, anti-fragment antiserum can be useful for determining structural relatedness of proteins, especially when used in competitive assays.


Subject(s)
Myelin Proteins/immunology , Animals , Cattle , Guinea Pigs , Humans , Immunochemistry , Mice , Myelin Proteolipid Protein , Peptide Fragments/immunology , Rats , Species Specificity
18.
J Biol Chem ; 260(7): 4371-7, 1985 Apr 10.
Article in English | MEDLINE | ID: mdl-3980482

ABSTRACT

Antiserum has been prepared against an isolated polypeptide fragment, designated BPS4, which comprises residues 181-211 of the bovine myelin proteolipid. The antiserum recognizes the intact bovine proteolipid protein but not several other polypeptide fragments within the molecule, nor the myelin basic protein, thus demonstrating specificity of the antiserum. In a competitive enzyme-linked immunosorbent assay, both the major proteolipid and the DM 20 bands observed on sodium dodecyl sulfate-polyacrylamide gels reacted equally well with the antiserum, indicating that the BPS4 segment is present in both molecular species. The rat myelin proteolipid protein cross-reacted with antiserum against the intact bovine protein but showed minimal cross-reactivity with the antiserum against the bovine BPS4 fragment. This was demonstrated in parallel experiments using three types of preparations, namely, sodium dodecyl sulfate-solubilized myelin, delipidated myelin, and isolated proteolipid apoprotein. The difference between the bovine and rat proteins, which presumably reflects amino acid sequence differences, is thus detectable by the antiserum against the polypeptide fragment but not by the antiserum against the intact protein. Isolated bovine myelin membranes did not bind the antiserum in the absence of detergent or without delipidation. On the other hand, in vesicles reconstituted with the intact bovine apoprotein, the BPS4 segment was oriented on the exterior face of the liposome where it was capable of binding antibody and was susceptible to Pronase digestion.


Subject(s)
Antibodies , Myelin Sheath/analysis , Peptide Fragments/immunology , Proteolipids/analysis , Amino Acid Sequence , Amino Acids/analysis , Animals , Cattle , Cross Reactions , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Rats , Species Specificity
19.
Microbios ; 63(255): 109-15, 1990.
Article in English | MEDLINE | ID: mdl-2259286

ABSTRACT

Novozym 234 at a concentration of 1.0 mg/ml yielded 95.5% spheroplasts within 30 min at 37 degrees C, pH 7.0, with 36% regeneration which was the highest level of regeneration observed. Yeast lytic enzyme at a concentration of 1.0 mg/ml yielded 99.8% spheroplasts with only 1.5% regeneration. Glusulase was significantly less active in producing osmotically sensitive cells. All three enzymes yielded significantly higher levels of osmotically sensitive cells when cells were harvested from the mid-logarithmic phase of growth compared with later growth phases. beta-Glucuronidase failed to produce osmotically sensitive cells regardless of the phase of growth from which cells were harvested.


Subject(s)
Saccharomyces/enzymology , Saccharomycetales/metabolism , Cell Wall/metabolism , Enzymes/metabolism , Glucuronidase/metabolism , Multienzyme Complexes/metabolism , Osmolar Concentration , Saccharomycetales/growth & development , Saccharomycetales/ultrastructure , Spheroplasts/physiology , Sulfatases/metabolism
20.
J Biol Chem ; 253(7): 2412-8, 1978 Apr 10.
Article in English | MEDLINE | ID: mdl-344314

ABSTRACT

A major cytochrome b peptide was purified from yeast mitochondria by a procedure involving solubilization in deoxycholic and cholic acids, ammonium sulfate fractionation, proteolytic digestion, and sucrose gradient centrifugation in the presence of Tween 80. The homogeneity of the purified protein was established by the criteria that the product was spectrally pure and yielded a single band on both sodium dodecyl sulfate polyacrylamide gel electrophoresis, and by gel isoelectric focusing. The purified cytochrome b polypeptide had absorption maxima at 562, 532, and 430 nm in the reduced form and at 525 to 570 nm and 419 nm in the oxidized form. The reduced minus oxidized difference spectra revealed absorption bands at 562, 532, and 430 nm at room temperature and 559, 529, and 429 nm at 77 K, respectively. The heme group was identified as protoheme by formation of the reduced pyridine hemochromogen. Treatment of the reduced form with carbon monoxide affected the absorption spectrum, indicating that the isolated hemoprotein was modified compared to native cytochrome b. The apparent molecular weight of the preparation was 28,000 based on sodium dodecyl sulfate polyacrylamide-gel electrophoresis and 28,800 based on sucrose gradient centrifugation. The isolated cytochrome b polypeptide showed a strong tendency to aggregate.


Subject(s)
Cytochromes , Saccharomyces cerevisiae/enzymology , Cytochromes/isolation & purification , Cytochromes/metabolism , Mitochondria/enzymology , Molecular Weight , Peptides/analysis , Spectrophotometry , Temperature
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