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1.
Article in English | MEDLINE | ID: mdl-34077361

ABSTRACT

Induced hypothermia has been broadly applied in neurological intensive care unit (NICU). Meanwhile, accidental hypothermia is also a threatening condition in daily life. It is meaningful to investigate the influences of temperature change on the cerebral blood flow (CBF). In the present study, temporal laser speckle image contrast analysis (tLASCA) was implemented to study the relative CBF change in cerebral artery, vein and capillary level under mild (35$\circ$C) and moderate (32$\circ$C) hypothermia. Twelve male Sprague-Dawley rats (300±50g) were anesthetized with sodium pentobarbital and randomly assigned to mild and moderate hypothermia groups (n=9 each). Laser speckle imaging trials were acquired from baseline (37$\circ$C), hypothermia (35$\circ$C or 32$\circ$C) and post-rewarming (37$\circ$C) phases. In the mild group, mean CBF in different vessels all increased throughout the hypothermic and post-rewarming phases. On the contrary, mean CBF reduced by 10% to 20% at 32$\circ$C and returned to ~95% of the baseline level during the post-rewarming session in the moderate group. Besides, in the moderate group, a CBF rebound in vein was found in the post-rewarming phase. Our results suggested that the CBF changed differently between mild and moderate hypothermia, which may worth for further study in clinical. And we demonstrated LSI as a promising method to achieve high spatiotemporal resolution CBF change with minimal invasion.

2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(6): 673-678, 2020 Jun 06.
Article in Chinese | MEDLINE | ID: mdl-32842285

ABSTRACT

Objective: To analyze the correlation between the changes of lung function and serum proinflammatory cytokines in workers occupationally exposed to toluene diisocyanate (TDI), and to explore the evaluation index of respiratory toxicity of TDI. Methods: In October 2014, 61 male workers engaged in TDI synthesis process, purification process, packaging process and the above production process in a TDI factory in western China were selected as TDI exposure group; 62 male enterprise managers who were not exposed to TDI and other known allergenic chemicals were selected as control group, which were matched at the age of workers in exposure group. The questionnaire survey obtained information such as gender, length of service, age, occupational history, exposed length of service and so on. The lung function indexes [forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC] and serum levels of interleukin (IL)-1 ß, IL-6, IL-8, tumor necrosis factor (TNF)-α, macrophage inflammatory factor-1 ß, monocyte chemoattractant factor-1 and vascular endothelial growth factor were measured. The urine was collected after the weekend shift, and the concentration of (TDA), the metabolite of TDI, was determined as the index of internal exposure. Spearman rank correlation was used to analyze the correlation between cytokines and lung function indexes, and multivariate linear regression was used to analyze the changes of lung function indexes and cytokines with TDI exposure concentration and time. Results: The median age (P5-P95) of the exposed group and the control group was 36.5 (24.0-51.0) and 38.0 (24.0-50.0) years, respectively. In the exposed group, the median length of service (P5-P95) was 6.94 (0.97-26.33) years, and the median concentration of TDA in urine was 15.56 (2.28-112.16) ng/ml. The three indexes of lung function, FVC, FEV1, FEV1/FVC and the levels of serum IL-8 and TNF-α were significantly lower than those in the control group (P<0.01). With the increase of exposure concentration and exposure time, the level of serum TNF-α, FVC and FEV1 decreased, and showed a good dose-effect and time-effect relationship (all Ptrend values< 0.05). Serum IL-8 and TNF-α were positively correlated with FVC, FEV1 and FEV1/FVC (all P values<0.01). Conclusion: The levels of serum inflammatory factors IL-8 and TNF-α in worker exposed to TDI are related to lung function indexes, which can be used as early evaluation indexes of respiratory toxicity induced by TDI.


Subject(s)
Occupational Exposure , Toluene 2,4-Diisocyanate , Adult , China , Cytokines , Humans , Lung , Male , Middle Aged , Vascular Endothelial Growth Factor A
3.
Zhonghua Gan Zang Bing Za Zhi ; 26(11): 842-846, 2018 Nov 20.
Article in Chinese | MEDLINE | ID: mdl-30616319

ABSTRACT

Objective: To investigates the role of piwi-interacting RNAs (piRNA) in the occurrence and development of hepatocellular carcinoma. Methods: Second-generation small RNA sequencing was performed on cancer and paracancerous tissues, metastatic and non-metastatic liver cancer tissues of patients with liver cancer, and the sequencing data were filtered out for the common RNA sequences to be repeated. The piRNA predictor was used to forecast the possible new piRNA merged with the downloaded known piRNA to screen out distinction. A miRanda algorithm was used to predict the corresponding target genes and functional enrichment analysis. piRNA was selected for experimental functional (migration) analysis. An independent t-test was used to compare means between the two groups. Results: 66 772 piRNAs (known 149) were obtained by sequencing. 241 piRNAs were found in cancer and paracancerous tissues, and 1 634 piRNAs were found in metastatic and non-metastatic tumors. Analysis of the GO and KEGG pathways of the target genes of differential piRNAs revealed that they were mainly involved in cell adhesion. An experimental functional analysis was performed on the selected Pirna (PIR1/97), which showed that it promoted the migration of hepatoma cells (LM3: t = 8.829, P < 0.05; PLC: t = 7.318, P < 0.05). Conclusion: The expression levels of piRNA in hepatocellular carcinoma patients with cancer and paracancerous tissues, metastasis and non-metastatic liver cancer tissues are different and it could be entailed in the metastasis process of hepatocellular carcinoma. Hence, experimental functional analysis is required for research and experimental confirmation.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Profiling/methods , Liver Neoplasms/genetics , RNA, Small Interfering/genetics , Adult , Carcinoma, Hepatocellular/pathology , Gene Expression Regulation, Neoplastic , Humans , Liver Neoplasms/pathology
4.
Zhonghua Er Ke Za Zhi ; 55(2): 115-119, 2017 Feb 02.
Article in Chinese | MEDLINE | ID: mdl-28173649

ABSTRACT

Objective: To explore the association between the phenotype and KCNB1 gene mutation. Method: Clinical information including physical features, laboratory and genetic data of one patient of mental retardation with refractory epilepsy from Department of Pediatrics, Xiangya Hospital in January 2016 was analyzed. This patient was discovered to have KCNB1 gene mutations through whole exome sequencing. Relevant information about KCNB1 gene mutation was searched and collected from Pubmed, CNKI, Human Gene Mutation Database(HGMD) and Online Mendelian Inheritance in Man(OMIM). Searching was done using "KCNB1" as a keyword. Result: A 3.5 years old boy who visited our hospital firstly at the age of 2 years because of development delay came for follow up as he developed seizures.The forms included tonic, clonic seizures and spasm. The condition became more severe 10 months later. Electroencephalogram(EEG) showed high frequency discharge (>85%). He had poor response to multiple anti-epileptic drugs, methylprednisolone and ketogenic diet. At the age of 3, he started to have mental regression. Whole exome-sequencing study (trios) identified a novel heterozygous mutation c. G1136T (p.G379V) in KCNB1, which is not available in the databases mentioned above. This is the first case report of KCNB1 gene mutation in China. Eight cases have been reported so far worldwide and all of them were diagnosed with refractory epilepsy. Those 8 reported cases of encephalopathy were all due to de novo mutation. Conclusion: The main clinical features of patients with KCNB1 mutations include severe to profound intellectual disability, intractable seizures, hypotonia and regression of cognition and motor activity which lead to poor prognosis.


Subject(s)
Epilepsy/genetics , Intellectual Disability/complications , Mutation , Shab Potassium Channels/genetics , Child, Preschool , China , Comorbidity , Developmental Disabilities , Diet, Ketogenic , Electroencephalography , Epilepsy/complications , Humans , Male , Phenotype , Seizures
5.
Article in Chinese | MEDLINE | ID: mdl-27866544

ABSTRACT

Objective: To investigate the effects of chronic exposure to monochloroacetic acid on the lung function and whole blood counts in occupational exposed workers, and provide new markers for occupational health surveillance. Methods: We conducted a cross-sectional molecular epidemiology study of 121 workers who were occupationally exposed to monochloroacetic acid and 69 unexposed workers frequency-matched by age and smoking status from the same geographic region. The lung function was measured by portable lung function instrument, and the lymphocyte subsets were measured by flow cytometry. Linear regression was used to test for differences in the levels of each marker between exposed and control workers. Results: FEV1.0/FVC was significantly decreased in both male and female workers exposed to monochloroacetic acid compared to unexposed workers (P<0.01) after adjusting for potential confounders, which were highly consistent when stratified by smoking status. Among male workers, monochloroacetic acid exposure was associated with significant decrease in the levels of CD8+ T cells (P<0.05) and monocytes (P<0.05) , and these statistically significant differences were observed between exposure and control workers only among smokers, not among non-smokers. However, there were no significant differences in the levels of whole blood cells and lymphocyte subsets between two groups among female workers. Conclusion: The chronic monochloroacetic acid exposure was associated with pulmonary dysfunction and immunosuppression, which mainly occurred among male workers and smokers.


Subject(s)
Lymphocyte Subsets , Acetates , Cross-Sectional Studies , Female , Humans , Lymphocyte Count , Male , Occupational Exposure
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 50(5): 418-22, 2016 May.
Article in Chinese | MEDLINE | ID: mdl-27141897

ABSTRACT

OBJECTIVE: To investigate the effect of occupational toluene diisocyanate(TDI) exposure on matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of metalloproteinase-1(TIMP-1), and analysis of the correlation of MMP-9,TIMP-1,MMP-9/TIMP-1 and lung function. METHODS: In October 2014, based on cluster sampling, we conducted a cross-sectional study in a TDI production factory located in China's western region. 61 exposed workers were recruited from workers engaged in packing, operating and checking. Based on different levels of the external exposure, the packers were classified as high exposed group, while operators and checkers as low exposed group. 58 factory managers, matching age and agent, were selected as controls, having same work intense and not contacting the TDI or other allergens. The questionnaire surveys were used to obtain the agent, age, work age, smoking and drinking, personal and family allergic history, occupational history, and the recent health conditions. The levels of MMP-9 and TIMP-1 in serum of subjects were determind by ELISA. The time weighted average concentrations (8h-TWA) were used to describe the levels of TDI air exposure in working environment. Spearman correlation assay was used to investigate the correlation of MMP-9, TIMP-1, MMP-9/TIMP-1 and lung function, exposure time. RESULTS: 8-hour TWA means of TDI air levels in exposed group, packers, operators and checkers were 0.39, 0.76, 0.25 mg/m(3), respectively . According to the external exposure concentration, the packers were classified as high exposed group, and the operators and checkers were classified as low exposed group. In controls, low exposed group and high exposed group, the levels of MMP-9, respectively, were (807.21±347.70),(586.91±317.50),(388.94±312.01) ng/ml (χ(2)=16.69, P<0.001), respectively, and the P50(P25-P75) of MMP-9/TIMP-1 were 4.67(2.87-6.68), 2.3(1.44-3.48), 1.11(0.59-1.48) (χ(2)=39.42, P<0.001), respectively, and the concentrations of TIMP-1, were (173.44±72.67), (236.12±51.98), (302.81±44.39) ng/ml (F=20.09, P< 0.001), respectively. The levels P50(P25-P75) of FVC, FEV1.0 and FEV1.0/FVC in exposed group were, 92.8% (86.0%-101.8%), 85.5%(76.7%-92.8%), 112.5(108.2-118.5), respectively, which were lower than that in control group (124.3%(107.9%-144.2%), 142.7%(119.1%-155.7%), 129.2(123.5-134))(Z values were 7.70, 8.97, 8.62, and all P<0.001). Spearman rank correlation analysis showed that levels of MMP-9 were positively associated with FEV1.0, and FEV1.0/FVC (r values were 0.27, 0.25, respectively, all P<0.05), and The levels of TIMP-1 were negatively associated with FVC, FEV1.0, and FEV1.0/FVC (r valuse were -0.33, -0.39, -0.39, all P<0.05).The levels of MMP-9 were negatively correlated with exposure time(r=-0.26, P=0.040). The positive correlations of MMP-9/TIMP-1 with FVC, FEV1.0, and FEV1.0/FVC were also found (r valuse were 0.34, 0.44, 0.40, all P<0.05). CONCLUSION: TDI exposure could induce the downs of MMP-9 and MMP-9/TIMP-1 associated with lung functions. The MMP-9 and MMP-9/TIMP-1,in a way, could reflect the respiratory inflammatory injury caused by TDI exposure.


Subject(s)
Matrix Metalloproteinase 9/metabolism , Occupational Exposure/adverse effects , Pulmonary Disease, Chronic Obstructive/metabolism , Tissue Inhibitor of Metalloproteinase-1/metabolism , Toluene 2,4-Diisocyanate/adverse effects , Adult , Aged , China , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , Forced Expiratory Volume , Humans , Lung/metabolism , Lung/pathology , Pulmonary Ventilation , Smoking , Vital Capacity
7.
Mult Scler ; 15(10): 1135-45, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19667008

ABSTRACT

BACKGROUND: Multiple sclerosis (MS) is a chronic, neurological disease characterized by targeted destruction of central nervous system (CNS) myelin. The autoimmune theory is the most widely accepted explanation of disease pathology. Circulating Th(1) cells become activated by exposure to CNS-specific antigens such as myelin basic protein. The activated Th(1) cells secrete inflammatory cytokines, which are pivotal for inflammatory responses. We hypothesize that enhanced production of inflammatory cytokines triggers cellular events within the dorsal root ganglia (DRG) and/or spinal cord, facilitating the development of neuropathic pain (NPP) in MS. NPP, the second worst disease-induced symptom suffered by patients with MS, is normally regulated by DRG and/or spinal cord. OBJECTIVE: To determine gene and protein expression levels of tumor necrosis factor-alpha (TNFalpha) within DRG and/or spinal cord in an animal model of MS. METHODS: Experimental autoimmune encephalomyelitis (EAE) was induced in adolescent female Lewis rats. Animals were sacrificed every 3 days post-disease induction. DRG and spinal cords were harvested for protein and gene expression analysis. RESULTS: We show significant increases in TNFalpha expression in the DRG and of EAE animals at peak disease stage, as assessed by clinical symptoms. CONCLUSION: Antigen-induced production of inflammatory cytokines such as TNFalpha within the DRG identifies a potential novel mechanism for MS-induced NPP.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/metabolism , Ganglia, Spinal/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Disability Evaluation , Disease Progression , Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/physiopathology , Female , Gene Expression , Immunohistochemistry , Multiple Sclerosis/complications , Multiple Sclerosis/metabolism , Pain/etiology , Polymerase Chain Reaction/methods , Rats , Rats, Inbred Lew , Reverse Transcriptase Polymerase Chain Reaction , Spinal Cord/metabolism , Tumor Necrosis Factor-alpha/genetics , Up-Regulation , User-Computer Interface
8.
J Biol Chem ; 260(22): 11986-93, 1985 Oct 05.
Article in English | MEDLINE | ID: mdl-4044585

ABSTRACT

We have analyzed the subcellular localization of 125I-labeled ribonuclease A and ribonuclease S-protein (residues 21-124) after erythrocyte-mediated microinjection into confluent cultures of IMR-90 human lung fibroblasts. Microinjected cells were fractionated by two consecutive Percoll gradients, and the distribution of radioactive ribonuclease A and S-protein was compared to patterns for known enzyme markers. Ribonuclease A is localized in the cytosol immediately after microinjection, but thereafter a portion of the microinjected enzyme is associated with lysosomes. We obtained similar results for ribonuclease S-protein except extensive association with a nonlysosomal intracellular structure is also evident. The effects of ammonium chloride on proteolysis indicate that ribonuclease A and ribonuclease S-protein are degraded at least in part by lysosomal pathways. Degradation of long-lived cellular proteins is inhibited by 17% in the presence of serum and by 35% in the absence of serum. The effects of ammonium chloride on catabolism of microinjected proteins are more variable. Inhibition in the presence and absence of serum ranged between 43 and 64% for both ribonuclease A and ribonuclease S-protein. To quantitatively assess the role of lysosomal and cytosolic pathways in the degradation of microinjected proteins, we have tagged proteins with the inert trisaccharide, [3H] raffinose. The radioactive degradation products of such proteins are completely retained within lysosomes since the lysosomal membrane is impermeable to [3H] raffinose coupled to lysine or small peptides. These studies show that ribonuclease A and S-protein are degraded almost entirely by lysosomes while bovine serum albumin is degraded principally in the cytosol. A mixture of rat liver cytosolic proteins is degraded approximately 60% in the cytosol and 40% by lysosomes confirming that both lysosomal and nonlysosomal pathways of proteolysis are important in confluent human fibroblasts.


Subject(s)
Lysosomes/metabolism , Peptide Fragments/metabolism , Ribonuclease, Pancreatic/metabolism , Ribonucleases/metabolism , Cell Fractionation , Cell Line , Centrifugation, Density Gradient , Cytosol/metabolism , Erythrocytes/metabolism , Fibroblasts/metabolism , Humans , Kinetics , Lysosomes/ultrastructure , Microinjections , Raffinose/metabolism
9.
J Cell Physiol ; 124(1): 1-8, 1985 Jul.
Article in English | MEDLINE | ID: mdl-3930513

ABSTRACT

The relationship between lipoproteins and growth of aortic smooth muscle cells has been a matter of controversy. We therefore reexamined this issue using serum-free defined media methodology. By themselves, LDL or HDL (50-500 micrograms/ml) from normolipemic human or bovine plasma produced little or no growth of homologous aortic smooth muscle cells incubated in serum-free medium that was supplemented with insulin and transferrin to maintain cell viability. In fact, LDL prepared in the absence of an antioxidant (BHT) was toxic to these cells. However, in the presence of maximally effective concentrations of platelet-derived growth factor (PDGF), LDL or HDL consistently increased the growth of homologous smooth muscle cells (up to twofold increased in DNA accumulation in 48 hr). Lipoproteins also augmented the growth response of arterial smooth muscle cells to fibroblast growth factor or epidermal growth factor. The mechanism of this effect was investigated further with HDL, because, in contrast to LDL, HDL apoproteins are water-soluble. Neither HDL delipidated by solvent extraction (apoHDL), purified bovine apoA-I, nor cholesterol added in the form of phospholipid vesicles appreciably increased PDGF-induced growth of bovine smooth muscle cells. However, HDL-like particles reconstituted by sonication of apoHDL with cholesterol and phospholipids did increase the growth of cultures of bovine smooth muscle cells treated with PDGF. Uptake of tritiated thymidine by cultures incubated with partially purified PDGF alone (10 micrograms/ml) was 5,693 +/- 235 dpm/24 hr compared to 10,381 +/- 645 dpm/24 hr (p less than 0.01) in the presence of both PDGF and reconstituted HDL-like particles (250 micrograms protein/ml). Thus both the lipid and protein components of HDL may be necessary for optimal potentiation of growth of mitogen-stimulated cells. These results indicate that lipoproteins from normolipemic sera are not bona fide growth factors but can potentiate the growth of mitogen-stimulated cells, perhaps by supplying exogenous cholesterol required for membrane biogenesis. This finding might be important in arterial injury when the release of PDGF and exposure to plasma lipoproteins could act in concert to stimulate the proliferation of smooth muscle cells.


Subject(s)
Lipoproteins/pharmacology , Muscle, Smooth, Vascular/cytology , Animals , Apolipoprotein A-I , Apolipoproteins A/pharmacology , Butylated Hydroxytoluene/pharmacology , Cattle , Cell Division/drug effects , DNA/analysis , Epidermal Growth Factor/pharmacology , Fibroblast Growth Factors/pharmacology , Humans , Lipoproteins, HDL/pharmacology , Lipoproteins, LDL/pharmacology , Platelet-Derived Growth Factor/pharmacology , Thymidine/metabolism , Time Factors
10.
Prog Clin Biol Res ; 180: 385-94, 1985.
Article in English | MEDLINE | ID: mdl-4034548

ABSTRACT

We are using ribonuclease A (RNase A) as a model protein to study how the degradative rates of proteins are regulated within cells. RNase A and several derivatives can be microinjected into confluent cultures of human fibroblasts using red cell-mediated microinjection. The half-life of RNase A is 80-100 hrs in cells maintained in the presence of serum, and the degradative rate is enhanced approximately two-fold upon serum withdrawal. The ability of fibroblasts to regulate breakdown of this protein depends on a small peptide region within the amino terminal twenty amino acids. This amino terminal peptide from RNase A can be covalently attached to unrelated proteins and will cause their catabolism to become serum responsive. The mechanism of degradation of RNase A involves lysosomal pathways both in the presence and absence of serum, and the enhanced catabolism during serum deprivation results from a two-fold increase in the rate of uptake of the protein by lysosomes. These findings suggest that autophagy, or some other process occuring in serum-deprived cells, can be highly selective.


Subject(s)
Ribonuclease, Pancreatic/metabolism , Fibroblasts/metabolism , Humans , Iodine Radioisotopes , Kinetics , Microinjections , Peptide Fragments/analysis , Ribonucleases/metabolism , Tritium
11.
Am J Anat ; 165(3): 225-48, 1982 Nov.
Article in English | MEDLINE | ID: mdl-6295129

ABSTRACT

Isolated guinea pig adrenocortical cells were maintained in long-term culture in order to perform sequential experiments on the same cell populations. The cells produced fluorogenic steroids, shown by thin-layer chromatography to be at least aldosterone, cortisol, and corticosterone. In addition, they increased production of these steroids when treated with either ACTH or dibutyryl cyclic AMP. Of particular interest was the fact that cultures treated for the initial 24-hour culture period with ACTH maintained enhanced levels of secretion for several days in absence of hormone and had an enhanced response to ACTH later in the culture period. Such enhancement of secretion was not seen following early treatment with dibutyryl cyclic AMP. The fine structure of the ACTH-treated cells was consistent with increased steroidogenesis. They possessed more smooth-surfaced endoplasmic reticulum, larger mitochondrial crystal surfaces, and larger Golgi complexes than the cells in untreated cultures.


Subject(s)
Adrenal Cortex/cytology , Adrenocorticotropic Hormone/pharmacology , Guinea Pigs/anatomy & histology , Steroids/biosynthesis , Adrenal Cortex/drug effects , Adrenal Cortex/metabolism , Adrenal Cortex/ultrastructure , Animals , Bucladesine , Cell Separation , Cells, Cultured , In Vitro Techniques , Male , Time Factors
12.
J Cell Biol ; 94(2): 241-52, 1982 Aug.
Article in English | MEDLINE | ID: mdl-6286688

ABSTRACT

This paper reports a quick, relatively simple and reproducible technique for obtaining populations of zona fasciculata and zona glomerulosa cells up to 80-90% pure, which can be maintained in vitro for study of adrenocortical cell function. Isolated guinea pig adrenocortical cells were separated on a 1-28% bovine serum albumin/Ca++, Mg++-free buffer gradient (wt/vol at 4% increments) using equilibrium density centrifugation (570 g, 30 min). Over 60% of the 8 x 10(5) viable cells/adrenal obtained in the total isolate were recovered after separation. 80% of the zona glomerulosa cells were found in the lower three bands of the gradient. 78% of the zona fasciculata cells were found in the top three bands. Of the cells in the first two bands, 78-91% were zona fasciculata cells, whereas of the cells in the bottom two bands 92-95% were zona glomerulosa cells. The cells retained the morphological characteristics of cells in situ and could be maintained in vitro for periods up to 11 d. They produced a wide variety of steroids, cortisol, corticosterone, aldosterone, 11-beta-hydroxyandrostenedione, deoxycortisol, deoxycorticosterone, cortisone, 18-hydroxycorticosterone, and a product tentatively identified as dehydroepiandrosterone, and they responded to ACTH in a dose-responsive manner with enhanced levels of steroid output. Zona glomerulosa-enriched populations differed from zona fasciculata-enriched populations in their abundant production of aldosterone and in the pattern of steroid production. None of the cultures responded to angiotensin II (100 pg/ml) with increased steroid production.


Subject(s)
Adrenal Cortex/cytology , Adrenal Cortex/metabolism , Adrenal Cortex/ultrastructure , Adrenocorticotropic Hormone/pharmacology , Aldosterone/biosynthesis , Animals , Cell Separation/methods , Cells, Cultured , Centrifugation, Density Gradient , Corticosterone/biosynthesis , Guinea Pigs , Hydrocortisone/biosynthesis , Microscopy, Electron , Microscopy, Phase-Contrast
13.
J Cell Biol ; 91(1): 184-94, 1981 Oct.
Article in English | MEDLINE | ID: mdl-7028761

ABSTRACT

Erythrocyte ghosts loaded with 125I-labeled proteins were fused with confluent monolayers of IMR-90 fibroblasts using polyethylene glycol. Erythrocyte-mediated microinjection of 125I-proteins did not seriously perturb the metabolism of the recipient fibroblasts as assessed by measurements of rates of protein synthesis, rates of protein degradation, or rates of cellular growth after addition of fresh serum. A mixture of cytosolic proteins was degraded after microinjection according to expected characteristics established for catabolism of endogenous cytosolic proteins. Furthermore, withdrawal of serum, insulin, fibroblast growth factor, and dexamethasone from the culture medium increased the degradative rates of microinjected cytosolic proteins, and catabolism of long-lived proteins was preferentially enhanced with little or no effect on degradation of short-lived proteins. Six specific polypeptides were degraded after microinjection with markedly different half-lives ranging from 20 to 320 h. Degradative rates of certain purified proteins (but not others) were also increased in the absence of serum, insulin, fibroblast growth factor, and dexamethasone. The results suggest that erythrocyte-mediated microinjection is a valid approach for analysis of intracellular protein degradation. However, one potential limitation is that some microinjected proteins are structurally altered by the procedures required for labeling proteins to high specific radioactivities. Of the four purified proteins examined in this regard, only ribonuclease A consistently showed unaltered enzymatic activity and unaltered susceptibility to proteolytic attack in vitro after iodination.


Subject(s)
Fibroblasts/metabolism , Proteins/metabolism , Cell Fusion , Cells, Cultured , Culture Media , Erythrocyte Membrane , Humans , Iodoproteins/metabolism , Isoelectric Point , Peptide Hydrolases/metabolism , Protein Biosynthesis , Protein Conformation , Structure-Activity Relationship
15.
Am J Hosp Pharm ; 34(6): 621-9, 1977 Jun.
Article in English | MEDLINE | ID: mdl-327800

ABSTRACT

Various aspects of the cephalosporin antibiotics are reviewed, including mode of action and mechanisms of bacterial resistance, antibacterial activity, clinical pharmacology, adverse reactions, and therapeutic use. There are no important therapeutic differences between the two oral agents, cephalexin and cephradine. For intramuscular injection, cephaloridine has largely been replaced by cefazolin which is equally well tolerated and not as nephrotoxic; further, cefazolin has a relatively long half-life which permits its administration three or four times daily. There are no substantial therapeutic differences among the cephalosporins most commonly used intravenously--cephalothin, cefazolin and cephapirin. However, cefazolin is administered in a lower dosage and somewhat less frequently.


Subject(s)
Bacteria/drug effects , Cephalosporins/pharmacology , Cephalosporins/adverse effects , Cephalosporins/metabolism , Cephalosporins/therapeutic use , Costs and Cost Analysis , Drug Hypersensitivity/etiology , Drug Resistance, Microbial , Humans , Kidney Diseases/chemically induced , Microbial Sensitivity Tests
17.
J Infect Dis ; 135 Suppl: S80-5, 1977 Mar.
Article in English | MEDLINE | ID: mdl-850096

ABSTRACT

Clindamycin and gentamicin were used in combination to treat 107 patients empirically for suspected aerobic-anaerobic sepsis. All patients were seriously ill and required initiation of treatment before results of cultures could be obtained. Infections included intraabdominal sepsis, hospital-acquired aspiration pneumonia, and soft tissue infections. Exudate cultured from 65 patients showed that the prediction of a mixed aerobic-anaerobic flora was correct in 46 patients (71%). Isolates from exudate included Escherichia coli, Bacteroides fragilis, clostridia, peptostreptococci, Proteus species, Klebsiella species, and Staphylococcus aureus. In 29 patients with bacteremia, the most frequent blood culture isolate was B. fragilis. Analysis of response to treatment showed that 92 patients were cured, five could not be evaluated adequately, and 10 failed to respond to therapy. Therapeutic failure primarily resulted from overwhelming sepsis, despite susceptibility of the pathogens to prescribed antibiotics.


Subject(s)
Bacterial Infections/drug therapy , Clindamycin/therapeutic use , Gentamicins/therapeutic use , Adult , Aerobiosis , Aged , Anaerobiosis , Bacteria/isolation & purification , Bacterial Infections/microbiology , Blood/microbiology , Drug Therapy, Combination , Humans , Middle Aged
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