Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In Th1 clones, TCR occupancy together with a costimulatory signal from APC results in IL-2 production. TCR occupancy alone results in unresponsiveness (anergy) to antigenic stimulation, a phenomenon that may be important for self-tolerance in vivo. Inasmuch as inositol phosphate production occurs during the induction of anergy other biochemical signals must be necessary for IL-2 production. Here we assess the role of tyrosine-specific protein kinases using the specific inhibitor, genistein. IL-2 secretion and responsiveness were very dependent on tyrosine-specific protein kinase activation and could be completely blocked under conditions where inositol phosphate generation occurred normally. Although anergy induction could also be blocked by inhibition of tyrosine-specific protein kinase activation this probably occurred indirectly via inhibition of inositol phospholipid hydrolysis. The differential susceptibility of IL-2 secretion and anergy induction to inhibition by genistein indicates that positive and negative outcomes of TCR occupancy may be mediated by distinct biochemical pathways.
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PMID:IL-2 secretion and T cell clonal anergy are induced by distinct biochemical pathways. 184 93

NMR spectroscopy has been used to characterize a new renal cell line, TALH-SVE.1, which is derived from the medullary thick ascending limb of Henle's loop. From the 31P-NMR spectrum of a suspension of TALH-SVE cells using the chemical shift of the intracellular inorganic phosphate a value of 7.24 +/- 0.04 for the steady-state intracellular pH (pHi) was determined at pHo = 7.40. In addition, the 31P-NMR spectrum indicated rather high levels of UDPG, a finding confirmed by 1H-NMR spectra of perchloric acid extracts. The 1H-NMR data also demonstrate the presence of 'organic osmolytes' such as inositol, sorbitol, choline and glycerophosphoryl choline (GPC). 13C-NMR spectra of perchloric acid extracts of TALH-SVE cells incubated with [2-13C]- and [3-13 C]alanine were used to determine the relative influx in the Krebs cycle via pyruvate carboxylase (PCB) versus the influx via pyruvate dehydrogenase (PDH). The ratio was 0.41, while about 52% of all acetyl-CoA entering the Krebs cycle was unlabeled. 13C-NMR experiments also indicated that TALH-SVE cells lack gluconeogenic activity. The NMR study presented indicates that TALH-SVE cells possess metabolic pathways similar to those of the parental cells.
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PMID:An NMR spectroscopic characterization of a new epithelial cell line, TALH-SVE, with properties of the renal medullary thick ascending limb of Henle's loop. 184 3

Presentation of Ag to type I CD4+ T cell clones by chemically fixed APC results in the induction of a long-lasting state of proliferative unresponsiveness in the T cell. Ag-specific TCR interactions do occur during this stimulation, as Ag- and Ia molecule-dependent increases in intracellular calcium free ion concentration can be demonstrated, yet free inositol phosphate generation is low and neither IL-2 synthesis nor proliferation occur. The addition of normal allogeneic accessory cells during this stimulation can restore the T cell proliferative response, as well as prevent the induction of unresponsiveness, thus defining an accessory cell-dependent costimulatory activity necessary for proliferation. We have now examined the biochemical effects of this costimulatory activity on early T cell activation. Normal accessory cell costimulatory activity was found to be incapable of augmenting the generation of free inositol phosphate in response to either fixed APC plus Ag or Con A alone. Furthermore, protein kinase C-dependent CD3 gamma-chain phosphorylation occurred in response to either fixed APC plus Ag or Con A alone, and the addition of normal accessory cells had no effect on the level of this phosphorylation. Finally, minimal CD3 zeta-chain tyrosine phosphorylation occurred during the induction of unresponsiveness with Ag and fixed APC alone and this also was not affected by the costimulatory activity. Our results demonstrate that T cell Ag receptor-mediated increases in intracellular calcium free ion concentration and protein kinase C activation occur independently of an accessory cell-derived costimulatory signal. In the absence of this costimulatory signal, these two intracellular second messengers are insufficient to induce a maximal proliferative response and in fact lead to a state of unresponsiveness.
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PMID:An accessory cell-derived costimulatory signal acts independently of protein kinase C activation to allow T cell proliferation and prevent the induction of unresponsiveness. 252 63

The minor phycobiliprotein beta 16.2 was isolated from the APC-core of phycobilisomes from the cyanobacterium Mastigocladus laminosus. Its complete amino-acid sequence and some spectral characteristics are presented. beta 16.2 consists of 169 amino acids and its molecular mass is 19,390 Da. A phycocyanobilin chromophore is covalently bound to a cysteine at position 84 as in all other phycobiliproteins. The first 138 amino acids are highly homologous to the N-terminal part of beta AP (62.5%), whereas the C-terminal part has no homology. The absorption maximum is situated at 624 nm, the fluorescence emission maximum at 644 nm in phosphate buffer, pH 7.0. Both values are slightly redshifted compared with alpha AP and beta AP.
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PMID:The phycobiliprotein beta 16.2 of the allophycocyanin core from the cyanobacterium Mastigocladus laminosus. Characterization and complete amino-acid sequence. 310 45

Vitamin D3 was determined in commercially fortified instant nonfat dried milk by using normal phase high pressure liquid chromatography (HPLC). The sample was extracted with dichloromethane with sodium phosphate tribasic solution added. The sample was cleaned up by using a Sep-Pak silica cartridge and then a microparticulate column containing 10 micrometer Partisil-10 PAC packing material. The final analysis was performed by using a normal phase HPLC system with 10 micrometer LiChrosorb NH2 column. Recovery of vitamin D3 at levels as low as 10000 IU/kg was 97.7% with a standard deviation of 3.9%.
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PMID:High pressure liquid chromatographic determination of vitamin D3 in instant nonfat dried milk. 625 Oct 24

In this multicenter study a nonnarcotic analgesic available for moderate pain, naproxen sodium, 550 mg, was compared to a combination that is used extensively for moderate to severe pain, aspirin, phenacetin, caffeine and codeine phosphate (APC/C) (60 mg of codeine phosphate). Women with pain after major gynecologic surgery reported a similar pattern in pain reduction with the two medications except for a relatively sharper increase in pain intensity between four and six hours after administration of APC/C. A smaller number of patient complaints suggested that naproxen sodium was better tolerated than APC/C.
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PMID:Naproxen sodium vs. a combination of aspirin, phenacetin, caffeine and codeine phosphate for pain after major gynecologic surgery. A multicenter comparison. 637 36

Significant and dramatic progress has been made in the diagnosis and treatment of women with ovarian carcinoma in the last 10 years, the results of which are now just being reflected in an increase in survival and cure rates. In early staged disease (Stage I and II) significant progress has been made concerning our understanding of the sites of subclinical metastasis when at surgery the tumor is clinically limited to the ovary or pelvis. A prospective study of 100 patients with Stages IA to IIB ovarian cancer who underwent restaging within 4 weeks of initial surgery will report this. Moreover, preliminary results of the first randomized therapeutic trials (melphalan versus observation; melphalan versus chromic phosphate [P-32]) in patients surgically staged and found to be Stage IA to IIB carcinoma will be discussed. For Stages IB to III, the 5-year survival rates comparing whole abdominal radiation by the moving strip technique to open field irradiation will be discussed. For advanced (Stage III and IV) ovarian carcinoma, the new techniques in debulking surgery will be illustrated. Finally, the significant progress in response rates, median duration of survival, disease-free survival, and 5-year survival rates made during the past 10 years will be presented. This will be done by comparing a unique group of 117 patients treated with melphalan alone, all of whom have been followed for 5 years or until death, to patients who received cisplatin combination chemotherapy--cyclophosphamide, hexamethylmelamine, Adriamycin (doxorubicin), and cisplatin (CHAD) or cisplatin, Adriamycin, and cyclophosphamide (PAC)--and have now been followed 3.4+ and 4+ years, respectively. What is clearly evident is that in the last decade there has been significant increase in response rates, median duration of survival, 3.4+-, 4+-, and 5-year survival rates and cure rates with the advent of debulking surgery and platinum-containing combination chemotherapy.
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PMID:Ovarian carcinoma. A decade of progress. 638 13

From 1982 through 1989, 56 patients with Stage III epithelial carcinoma of the ovary received intraperitoneal chromic phosphate following chemotherapy and second look (52 pts) or as the only postsurgical management (4 pts). Median follow-up was 48 months (range of 24 to 108 months). The 4 patients treated following primary surgery with P-32 without chemotherapy had microscopic abdominal disease (3 pts) or complete reduction of gross abdominal disease (1 pt), and their 5-year survival was 100%. Of the 52 patients treated with P-32 following PAC chemotherapy, 23 were pathologic negative, 15 had microscopic residual, and 14 had gross residual at second look. The 5-year survival following second look was 75% for negative, 48% for microscopic, and 32% for gross residual. There were 4 Grade 3 GI complications (7%). There were no complications in the 38 patients who received the P-32 within 12 hr of surgery. The use of P-32 as an adjuvant for Stage I and II epithelial carcinoma of ovary has been found to be effective in prior GOG trials. We have expanded the selection criteria in patients with Stage III carcinoma to include those who can be surgically reduced to microscopic residual at primary surgery or second look following chemo reduction. Because of multiple prognostic variables affecting survival in Stage III ovarian cancer, a randomized study with control arm would be necessary to draw firm conclusions regarding the effectiveness of P-32. The 5-year survival in this group of patients compares favorably to published reports.
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PMID:Use of P-32 in stage III epithelial carcinoma of the ovary. 802 Aug 36

Oligonucleotides containing 2'-O-aminopropyl-substituted RNA have been synthesized. The 2'-O-(aminopropyl)adenosine (APA), 2'-O-(aminopropyl)cytidine (APC), 2'-O-(aminopropyl)-guanosine (APG), and 2'-O-(aminopropyl)uridine (APU) have been prepared in high yield from the ribonucleoside, protected, and incorporated into an oligonucleotide using conventional phosphoramidite chemistry. Molecular dynamics studies of a dinucleotide in water demonstrates that a short alkylamine located off the 2'-oxygen of ribonucleotides alters the sugar pucker of the nucleoside but does not form a tight ion pair with the proximate phosphate. A 5-mer with the sequence ACTUC has been characterized using NMR. As predicted from the modeling results, the sugar pucker of the APU moiety is shifted toward a C3'-endo geometry. In addition, the primary amine rotates freely and is not bound electrostatically to any phosphate group, as evidenced by the different sign of the NOE between sugar proton resonances and the signals from the propylamine chain. Incorporation of aminopropyl nucleoside residues into point-substituted and fully modified oligomers does not decrease the affinity for complementary RNA compared to 2'-O-alkyl substituents of the same length. However, two APU residues placed at the 3'-terminus of an oligomer gives a 100-fold increase in resistance to exonuclease degradation, which is greater than observed for phosphorothioate oligomers. These structural and biophysical characteristics make the 2'-O-aminopropyl group a leading choice for incorporation into antisense therapeutics. A 20-mer phosphorothioate oligonucleotide capped with two phosphodiester aminopropyl nucleotides targeted against C-raf mRNA has been transfected into cells via electroporation. This oligonucleotide has 5-10-fold greater activity than the control phosphorothioate for reducing the abundance of C-raf mRNA and protein.
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PMID:2'-O-aminopropyl ribonucleotides: a zwitterionic modification that enhances the exonuclease resistance and biological activity of antisense oligonucleotides. 897 41

We compared the processing and presentation of the model Ag, hen-egg white lysozyme (HEL) expressed in C3.F6 APC as a fusion protein to three different acid hydrolases: cathepsin D, to an unglycosylated form of cathepsin D, and to pepsinogen. As expected from the biology of mannose 6-phosphate (Man-6-P)-containing enzyme, cathepsin D-HEL was delivered to the endosomal/lysosomal system. In contrast, the unglycosylated cathepsin D-HEL was retained in ER/Golgi and some was found in lysosomes. Most of pepsinogen-HEL was rapidly secreted from the APC. All transfectants presented HEL epitopes to T cell hybridomas. Regardless of the main route of traffic of the proteins, the strong I-Ak binding epitope HEL 48-62 was well presented by all. The biochemical forms of this epitope were identical for all. Three other epitopes of HEL that bind I-Ak with less affinity were processed equally well by unglycosylated cathepsin D-HEL and HEL-Ld. The glycosylated cathepsin D-HEL was less efficient in generating the 114-129 epitope. Pepsinogen-HEL was the less efficient of all transfectants in presenting these subdominant epitopes. Soluble cathepsin D-HEL recovered from culture supernatant was strongly immunogenic when added to C3.F6. The uptake was inhibited by free Man-6-P, indicating that the surface Man-6-P receptor can effectively deliver proteins to the class II MHC system.
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PMID:Presentation on class II MHC molecules of endogenous lysozyme targeted to the endocytic pathway. 905


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