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PubMed2004

Localization of ascorbic acid, ascorbic acid oxidase, and glutathione in roots of Cucurbita maxima L.

To understand the function of ascorbic acid (ASC) in root development, the distribution of ASC, ASC oxidase, and glutathione (GSH) were investigated in cells and tissues of the root apex of Cucubita maxima. ASC was regularly distributed in the cytosol of almost all root cells, with the exception of quiescent centre (QC) cells. ASC also occurred at the surface of the nuclear membrane and correspondingly in the nucleoli. No ASC could be observed in vacuoles. ASC oxidase was detected by immunolocalization mainly in cell walls and vacuoles. This enzyme was particularly abundant in the QC and in differentiating vascular tissues and was absent in lateral root primordia. Administration of the ASC precursor L-galactono-gamma-lactone markedly increased ASC content in all root cells, including the QC. Root treatment with the ASC oxidized product, dehydroascorbic acid (DHA), also increased ASC content, but caused ASC accumulation only in peripheral tissues, where DHA was apparently reduced at the expense of GSH. The different pattern of distribution of ASC in different tissues and cell compartments reflects its possible role in cell metabolism and root morphogenesis.

Amaryllidaceae Alkaloids↗

PubMed1997

The Ascorbate Carrier of Higher Plant Plasma Membranes Preferentially Translocates the Fully Oxidized (Dehydroascorbate) Molecule.

Recently, the uptake of 14C-labeled ascorbate (ASC) into highly purified bean (Phaseolus vulgaris L.) plasma membrane vesicles was demonstrated in our laboratory. However, the question of the redox status of the transported molecule (ASC or dehydroascorbate [DHA]) remained unanswered. In this paper we present evidence that DHA is transported through the plasma membrane. High-performance liquid chromatography analysis of the redox status of ASC demonstrated that freshly purified plasma membranes exhibit a high ASC oxidation activity. Although it is not yet clear whether this activity is enzymatic, it complicates the interpretation of ASC-transport experiments in vitro and in vivo. In an attempt to correlate the ASC redox status to transport of the molecule, the ability of different compounds to reduce DHA was analyzed and their effect on ASC-transport activity tested. Administering of various reductants resulted in different levels of inhibition of ASC uptake (dithiothreitol > dithioerythritol > [beta]-mercaptoethanol > [beta]-mercaptopropanol). Glutathione, cysteine, dithionite, and thiourea did not significantly affect ASC transport. Statistical analysis indicated a strong correlation of the Spearman rank correlation coefficient (Rs) of 0.919 (P = 0.0005, n = 9) between the level of ASC oxidation and the amount of transported molecules into the vesicles. The administering of ASC oxidants such as ferricyanide and ASC oxidase resulted in a stimulated ASC uptake into the plasma membrane vesicles. Together, our results demonstrate that a vitamin C carrier in purified bean plasma membranes translocates DHA from the apoplast to the cytosol.

Journal Article↗

PubMed1992

Antibody-secreting cells in human peripheral blood after oral immunization with an inactivated enterotoxigenic Escherichia coli vaccine.

Vaccine antigen-specific antibody-secreting cell (ASC) responses in peripheral blood of healthy adult volunteers were studied after oral immunization with a prototype enterotoxigenic Escherichia coli (ETEC) vaccine by means of the enzyme-linked immunospot technique. Three doses of vaccine consisting of formalin-killed ETEC bacteria expressing fimbrial colonization factor antigens I and II (CFA/I and CFA/II) in combination with purified cholera toxin B subunit (CTB) were given 2 weeks apart. The ASC responses were detected 7 days after each immunization. Immunoglobulin A (IgA) was the predominant isotype produced by CFA/I- as well as CFA/II-specific ASCs. Moderate CFA/I- and CFA/II-specific IgM-secreting ASC (IgM-ASC) responses were also seen, whereas IgG-ASC responses to either of the CFAs were negligible. The ASC responses to CTB, on the other hand, comprised both IgA- and IgG-ASCs, with few if any specific IgM-ASCs. Almost 90% of the volunteers developed CFA-specific ASC responses after vaccination. Maximal CFA-specific ASC responses were usually observed after a single dose or two doses of vaccine. A third dose of vaccine did not result in increased but rather resulted in decreased magnitudes of CFA-specific ASC responses. Furthermore, it was found that CTB did not function as a mucosal adjuvant, since CFA-specific ASC responses were not enhanced by the simultaneous administration of CTB. These results suggest that two oral doses of ETEC vaccine induce a strong mucosal immune response, as reflected by the presence of large numbers of antigen-specific mucosal B cell immunoblasts in the blood.

Administration, Oral↗

PubMed2005

Should women with atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion, receive reflex human papillomavirus-DNA testing?

BACKGROUND: The 2001 American Society for Colposcopy and Cervical Pathology Consensus Guidelines recommend that women who have Papanicolaou (Pap) smears diagnosed as atypical squamous cells (ASC), cannot exclude high-grade squamous intraepithelial lesion (HSIL) (ASC-H) should be referred for immediate colposcopic examination. The objective of this pilot study was to evaluate whether reflex human papillomavirus (HPV)-DNA testing performed on smears diagnosed as ASC-H may obviate the need for immediate colposcopic examination. METHODS: All ThinPrep Pap smears that were diagnosed as ASC-H or atypical squamous metaplastic cells (ASMT) between 2001-2003 and that had HPV-DNA testing and subsequent histologic and/or cytologic follow-up were evaluated. Those smears that were diagnosed as ASMT were reviewed and reclassified under the 2001 Bethesda System as either ASC of undetermined significance (ASCUS) or ASC-H. Smears that were diagnosed as ASCUS were excluded from the study. RESULTS: The study included of 48 smears that were diagnosed as ASC-H. All patients with biopsy-proven HSIL had positive high-risk (HR)-HPV results (100% negative predictive value). Approximately 80% of patients with ASC-H who had biopsy-proven, low-grade intraepithelial lesion on follow-up had positive HR-HPV results. Among the patients who had ASC-H with negative follow-up, 50% had positive HR-HPV results, and 50% had negative HR-HPV results. CONCLUSIONS: Among patients with ASC-H, a negative HR-HPV result was found to be an excellent predictor of the absence of HSIL. The results of this pilot study suggested that HPV-DNA testing may serve as a means to better select which patients with ASC-H on Pap smear should undergo colposcopic examination. This approach potentially may reduce medical costs and eliminate the need for routine colposcopic examination among patients with ASC-H Pap smears.

Colposcopy↗

PubMed2005

Expression of exogenous or endogenous green fluorescent protein in adipose tissue-derived stromal cells during chondrogenic differentiation.

Pluripotent stem cells within the adipose stromal compartment, termed adipose-derived stromal cells (ASCs), have the potential to differentiate into a variety of cell lineages both in vitro and in vivo. Imaging with expression of exogenous or endogenous green fluorescent protein (GFP) reporters facilitates the detailed research on ASCs' physiological behavior during differentiation in vivo. This study was aimed to confirm whether ASCs expressing GFP still could be induced to chondrogenesis, and to compare the expression of exogenous or endogenous GFP in ASCs during chondrogenic differentiation. ASCs were harvested from inguinal fat pads of normal nude mice or GFP transgenic mice. Monolayer cultures of ASCs from normal mice were passaged three times and then infected with replication-incompetent adenoviral vectors carrying GFP genes. Allowed to recover for 5 days, Ad/GFP infected ASCs were transferred to chondrogenic medium as well as the ASCs from transgenic mice cultured in vitro over the same passages. The level of GFP in transgenic ASCs maintained stable till 3 months after chondrogenic induction. Whereas, high level of GFP expression in Ad/GFP infected ASCs could last for only 8 weeks and then declined stepwise. Important cartilaginous molecules such as SOX9, collagen type I, collagen type II, aggrecan, collagen type X were assessed using immunocytochemistry, RT-PCR, and Western Blot. The results indicated that no matter the GFP was exogenous or endogenous, it did not influence the chondrogenic potential of ASCs in comparison with the normal controls. Moreover, chondrogenic lineages from ASCs also underwent phenotypic modulation called dedifferentiation as a result of long-term culture in monolayers similar to normal chondrocytes.

Adipose Tissue↗

PubMed2003

Cytoprotection against ischemia-induced DNA cleavages and cell injuries in the rat liver by pro-vitamin C via hydrolytic conversion into ascorbate.

To search a regimen for prevention of post-ischemic reperfusional (I/R) injuries, I/R in the liver was induced by 30-min clamping and subsequent unfastening of the portal vein of a rat, which underwent previous i.v. administration with ascorbic acid (Asc) of 1 mg/kg or the autooxidation-resistant pro-vitamin C, 2-O-alpha-D-glucosylated Asc (Asc2G) or 2-O-phosphorylated Asc (Asc2P) of 1 mg Asc equivalent/kg from the viewpoint of utilization of antioxidants that can promptly scavenge I/R-derived reactive oxygen species. The administration with Asc, Asc2P or Asc2G prevented some features of hepatic I/R injuries such as release of hepatic marker enzymes GOT and GPT into the blood vessel, cellular degenerative symptoms including vacuolation and cell fragmentation, and nuclear DNA strand cleavage as detected by TUNEL staining. The preventive effects on I/R injuries were in the order: Asc2G > Asc2P >> Asc. This order of preventive degrees of three anti-oxidants is partly attributable to proper efficiency of conversion to vitamin C and stability in blood stream; Asc2P was moderately converted to a free monoanion form of Asc in human serum, but, in rat serum, so efficiently converted to Asc as to undergo the resultant oxidative decomposition before reaching the liver, whereas Asc2G underwent scarce conversion to Asc in human serum but moderate conversion in rat serum, suggesting that Asc2P might be less cytoprotective against I/R injury than Asc2G in the rat liver in a way different from the human liver. In contrast Asc was so susceptible to autooxidation as to be rapidly decomposed in either rat or human serum. The concentrations of ascorbyl radicals (AscR) in serum were unchanged during I/R for sham-operated rats, but appreciably diminished time-dependently for I/R-operated rats as shown by ESR spectra. A marked increase in serum AscR occurred in rats receiving Asc, Asc2G or Asc2P, but it was time-dependently restored down to the pre-ischemic level of AscR in I/R-operated rats more rapidly than in sham-operated rats. Thus, hepatic I/R injuries were shown to be prevented more markedly by Asc2G or Asc2P than by Asc, which is attributable to efficiencies of both vitamin C conversion and subsequent AscR retention.

Animals↗

PubMed2002

Effect of asymmetric modification on the conformation of ascidiacyclamide analogs.

Ascidiacyclamide (ASC), cyclo(-Ile1-Oxz2-d-Val3-Thz4-)2 (Oxz=oxazoline and Thz=thiazole) has a C2-symmetric sequence, and the relationships between its conformation and symmetry have been studied. In a previous study, we performed asymmetric modifications in which an Ile residue was replaced by Gly, Leu or Phe to disturb the symmetry [Doi et al. (1999) Biopolymers49, 459-469]. In this study, the modifications were extended. The Ile1 residue was replaced by Gly, Ala, aminoisobutyric acid (Aib), Val, Leu, Phe or d-Ile, and the d-Val3 residue was replaced by Val. The structures of these analogs were analyzed by X-ray diffraction, 1H NMR and CD techniques. X-Ray diffraction analyses revealed that the [Ala1], [Aib1] and [Phe1]ASC analogs are folded, whereas [Val1]ASC has a square form. These structures are the first examples of folded structures for ASC analogs in the crystal state and are similar to the previously reported structures of [Gly1] and [Phe1]ASC in solution. The resonances of amide NH and Thz CH protons linearly shift with temperature changes; in particular, those of [Aib1], [d-Ile1] and [Val3]ASCs exhibited a large temperature dependence. DMSO titration caused nonlinear shifts of proton resonances for all analogs and largely affected [d-Ile1] and [Val3]ASCs. A similar tendency was observed upon the addition of acetone to peptide solutions. Regarding peptide concentration changes, amide NH and Thz CH protons of [Gly1]ASC showed a relatively large dependence. CD spectra of these analogs indicated approximately two patterns in MeCN solution, which were related to the crystal structures. However, all spectra showed a similar positive Cotton effect in TFE solution, except that of [Val3]ASC. In the cytotoxicity test using P388 cells, [Val1]ASC exhibited the strongest activity, whereas the epimers of ASC ([d-Ile1] and [Val3]ASCs), showed fairly moderate activities.

Amino Acid Substitution↗

PubMed2002

Increased antioxidant potential of combined topical vitamin E and C against lipid peroxidation of eicosapentaenoic acid in pig skin induced by simulated solar radiation.

PURPOSE: To study the protective effect of topically applied vitamin E (TOC), vitamin C (ASC), or a combination of both, against the lipid peroxidation of eicosapentaenoic acid (EPA) induced by simulated solar radiation (SSR). MATERIAL AND METHODS: EPA (25 nmol cm(-2)) was topically applied to pig skin explants, followed by increasing doses of TOC and ASC, either alone or combined. Epidermal lipid peroxidation was assessed after 15 min of exposure to SSR (resulting in a UVA and UVB dose of 18 and 3 kJ m(-2), respectively). SSR-induced changes in the levels of TOC and ASC were determined in the stratum cornaeum and the viable epidermis. RESULTS: SSR exposure of EPA-treated pig skin resulted in a twofold increase in epidermal lipid peroxidation (p <0.005) which was reduced by topically applied TOC or ASC 60 min before SSR exposure (p <0.05). Compared with TOC (5 nmol cm(-2)), a 400-fold higher ASC dose was needed and only TOC provided complete protection against the lipid peroxidation of EPA. The levels of both TOC and ASC clearly increased in both skin compartments by increasing the applied dose of these two compounds (p <0.05). In contrast to ASC, TOC was consumed by up to 55-70% during SSR exposure (p <0.05). Compared with separate application, combined TOC and ASC efficiently protected against lipid peroxidation of EPA at doses that were five and 200 times lower, respectively. In the presence of low ASC doses, 70-100% of epidermal TOC was regenerated during SSR exposure (p <0.05). CONCLUSIONS: Topically applied TOC and ASC protect against SSR-induced lipid peroxidation of EPA. The synergism between TOC and ASC resulted in a more efficient protection at substantially lower doses of both antioxidants. Co-supplementation of EPA with TOC and/or ASC might improve the beneficial biological effects of EPA.

Administration, Topical↗

PubMed2006

Adipose tissue-derived mesenchymal stem cell yield and growth characteristics are affected by the tissue-harvesting procedure.

BACKGROUND: Adipose tissue contains a stromal vascular fraction that can be easily isolated and provides a rich source of adipose tissue-derived mesenchymal stem cells (ASC). These ASC are a potential source of cells for tissue engineering. We studied whether the yield and growth characteristics of ASC were affected by the type of surgical procedure used for adipose tissue harvesting, i.e. resection, tumescent liposuction and ultrasound-assisted liposuction. METHODS: Frequencies of ASC in the stromal vascular fraction were assessed in limiting dilution assays. The phenotypical marker profile of ASC was determined, using flow cytometry, and growth kinetics were investigated in culture. ASC were cultured under chondrogenic and osteogenic conditions to confirm their differentiation potential. RESULTS: The number of viable cells in the stromal vascular fraction was affected by neither the type of surgical procedure nor the anatomical site of the body from where the adipose tissue was harvested. After all three surgical procedures, cultured ASC did express a CD34+ CD31- CD105+ CD166+ CD45- CD90+ ASC phenotype. However, ultrasound-assisted liposuction resulted in a lower frequency of proliferating ASC, as well as a longer population doubling time of ASC, compared with resection. ASC demonstrated chondrogenic and osteogenic differentiation potential. DISCUSSION: We conclude that yield and growth characteristics of ASC are affected by the type of surgical procedure used for adipose tissue harvesting. Resection and tumescent liposuction seem to be preferable above ultrasound-assisted liposuction for tissue-engineering purposes.

Adipocytes↗

PubMed2002

Activating signal cointegrator 1 is highly expressed in murine testicular Leydig cells and enhances the ligand-dependent transactivation of androgen receptor.

Activating signal cointegrator 1 (ASC-1) has been recently reported as a coactivator of some nuclear receptors. In the present study, we have analyzed the expression of ASC-1 in the mouse testis and investigated its capacity to modulate the transcriptional activity of androgen receptor (AR). We found that although ASC-1 mRNA was ubiquitously expressed at a low level in mouse tissues, a couple of testis-specific mRNAs were expressed in the adult testis. Cloning of one testis-specific variant revealed that the ubiquitous and testis-specific transcripts of ASC-1 share at least the same open reading frame. The expression of the testis-specific ASC-1 mRNAs was developmentally regulated, and the onset of their expression coincided with the initiation of spermatogenesis. In situ hybridization of mouse testis with ASC-1 antisense probe demonstrated predominant expression of ASC-1 in the interstitial Leydig cells that express AR. Moreover, yeast two-hybrid tests and glutathione S-transferase pull-down assays revealed that ASC-1 associates directly with AR and that the hinge domain of AR and a putative zinc-finger motif of ASC-1 are major determinants for their interaction. Transient transfection assays performed by expressing ASC-1 in combination with AR and an androgen-responsive reporter gene showed that ASC-1 moderately alters the induction of the reporter gene. Taken together, these results suggest that ASC-1 may function as an AR coregulator and have a role in testicular functions.

Animals↗

PubMed1995

Induction of compartmentalized B-cell responses in human tonsils.

The capacity of tonsillar and nasal mucosal lymphoid tissues to serve as induction sites of local and/or distant B-cell responses in humans has been examined. The frequencies of vaccine-specific antibody-secreting cells (ASC) in cell suspensions from palatine tonsils (PT) and adenoids were determined after local (intra-tonsillar [i.t.]) and regional (intranasal [i.n.]) immunizations as well as peroral and parenteral immunizations with cholera and tetanus toxoids. While peroral and parenteral immunizations evoked negligible ASC responses in PT, i.t. vaccination induced a substantial ASC response which consisted of immunoglobulin G (IgG) and IgA ASC. Responses were highly restricted to immunized tonsils. Primary immunization in one PT followed by a second immunization of both PT evoked a larger ASC response in the primed tonsil. The latter ASC response was associated with higher frequencies of ASC precursors in primed tonsils. Furthermore, two i.n. immunizations induced only modest ASC responses in PT, although such immunizations evoked high ASC responses in adenoids. However, both i.t. and i.n. routes of immunization induced specific peripheral blood ASC responses, suggesting that a fraction of B cells activated in tonsils or in nasal mucosa may enter the circulation and disseminate to distant organs. These blood ASC responses preceded increases in both IgA and IgG antibody titers in nasal washes and serum samples. However, vaccine-specific ASC were not detected in duodenal cell suspensions from volunteers who had received i.t. or i.n. immunizations. Collectively, these results indicate that tonsils can serve as expression sites of locally induced antibody responses and support the development of immunological memory. Furthermore, tonsils may serve as powerful inductive sites for immune responses expressed in the upper aerodigestive tract.

Adenoids↗

PubMed2002

Immune responses to novel pneumococcal proteins pneumolysin, PspA, PsaA, and CbpA in adenoidal B cells from children.

Studies of mice suggest that pneumococcal proteins, including PspA, pneumolysin, PsaA, and CbpA, are promising vaccine candidates. To determine whether these proteins are good mucosal immunogens in humans, adenoidal lymphocytes from 20 children who had adenoidectomies were isolated and tested by ELISpot for antigen-specific antibody-secreting cells (ASCs). Cells were also cultured for 7 days in the presence of a concentrated culture supernatant (CCS) from a type 14 strain of pneumococcus which contained secreted pneumococcal proteins, including PspA, pneumolysin, PsaA, and CbpA, and then tested by ELISpot. ELISpot assays done on freshly isolated cells detected ASCs to all four antigens in most children studied. However, there were differences both between antigens and between isotypes. The densities of immunoglobulin G (IgG) ASCs against both PsaA and CbpA were significantly higher than those of ASCs for PspA and PdB (pneumolysin toxoid B) (P < 0.001). For all antigens, the numbers of IgA ASCs tended to be lower than those of both IgG and IgM ASCs. The numbers of anti-CbpA and -PsaA IgA ASCs were higher than those of anti-PdB IgA ASCs (P < 0.01). Concentrations of IgA antibodies to PspA and PsaA in saliva correlated with the numbers of IgA ASCs to PspA and PsaA in freshly isolated adenoidal cells, but no such correlation was found between salivary IgG antibody concentrations and IgG ASCs to the four antigens in adenoidal cells. In cultured cells, anti-PspA, -PsaA, and -CbpA IgG ASCs proliferated significantly, but only two of eight samples showed >2-fold increases in anti-CbpA and -PspA IgA ASCs after CCS stimulation. The results suggest that CbpA, PsaA, and PspA may be good upper respiratory mucosal antigens in children. Adenoids may be important inductive sites for memory IgG responses and important sources of salivary IgA. Some protein antigens may also prime for mucosal IgA memory. These data support the effort to explore mucosal immunization against pneumococcal infection.

Adenoids↗

PubMed2003

Apoptosis-associated speck-like protein containing a caspase recruitment domain is a regulator of procaspase-1 activation.

Apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC)/target of methylation-induced silencing/PYCARD represents one of only two proteins encoded in the human genome that contains a caspase recruitment domain (CARD) together with a pyrin, AIM, ASC, and death domain-like (PAAD)/PYRIN/DAPIN domain. CARDs regulate caspase family proteases. We show here that ASC binds by its CARD to procaspase-1 and to adapter proteins involved in caspase-1 activation, thereby regulating cytokine pro-IL-1beta activation by this protease in THP-1 monocytes. ASC enhances IL-1beta secretion into the cell culture supernatants, at low concentrations, while suppressing at high concentrations. When expressed in HEK293 cells, ASC interferes with Cardiak/Rip2/Rick-mediated oligomerization of procaspase-1 and suppresses activation this protease, as measured by protease activity assays. Moreover, ASC also recruits procaspase-1 into ASC-formed cytosolic specks, separating it from Cardiak. We also show that expression of the PAAD/PYRIN family proteins pyrin or cryopyrin/PYPAF1/NALP3 individually inhibits IL-1beta secretion but that coexpression of ASC with these proteins results in enhanced IL-1beta secretion. However, expression of ASC uniformly interferes with caspase-1 activation and IL-1beta secretion induced by proinflammatory stimuli such as LPS and TNF, suggesting pathway competition. Moreover, LPS and TNF induce increases in ASC mRNA and protein expression in cells of myeloid/monocytic origin, revealing another level of cross-talk of cytokine-signaling pathways with the ASC-controlled pathway. Thus, our results suggest a complex interplay of the bipartite adapter protein ASC with PAAD/PYRIN family proteins, LPS (Toll family receptors), and TNF in the regulation of procaspase-1 activation, cytokine production, and control of inflammatory responses.

Adaptor Proteins, Signal Transducing↗

PubMed2004

Decreased dosage of acidified sodium chlorite reduces microbial contamination and maintains organoleptic qualities of ground beef products.

Acidified sodium chlorite (ASC) spray was evaluated at decreased dosages and application rates to determine its efficacy for reducing bacterial contamination on boneless beef trimmings used for production of raw ground beef products while maintaining desirable consumer qualities in the finished ground beef products. Two different applications of ASC (600 ppm applied at a rate of 1.3 oz/lb and 300 ppm applied at a rate of 1 oz/lb) were used to treat boneless beef trimmings before grinding. The effect of ASC treatment on 50/50 lean beef trimmings was greater than on 90/10 trimmings. ASC at 600 ppm reduced both the aerobic plate counts (APC) and Enterobacteriaceae counts (EBC) by 2.3 log CFU/g on 50/50 trimmings, whereas treatment with 300 ppm ASC reduced APC and EBC of 50/50 trimmings by 1.1 and 0.7 log CFU/g, respectively. Ground beef formulations of 90/10 and 73/27 were produced from the treated boneless beef trim and packaged in chubs and in modified atmosphere packaging. The efficacy of ASC spray treatment to inhibit APC and EBC over the shelf life of each ground beef product was monitored. The APC and EBC in ground beef chubs were reduced by 1.0 to 1.5 log CFU/g until day 20. The APC and EBC for products in modified atmosphere packaging were reduced 1.5 to 3.0 log CFU/g throughout their shelf life. Both decreased dosages of ASC were equally effective on 90/10 lean ground beef, but the 300 ppm ASC treatment was slightly better at reducing the EBC of 73/27 ground beef. The organoleptic qualities (color, odor, and taste) of the ground beef products treated with 300 ppm ASC were found to be superior to those treated with 600 ppm ASC. Our results indicated that decreased dosages of ASC reduce contamination and lengthen the shelf life of ground beef. Furthermore, the 300 ppm ASC treatment reduced bacterial counts while maintaining desirable organoleptic ground beef qualities.

Animals↗

PubMed2003

Adenosquamous histology predicts a poor outcome for patients with advanced-stage, but not early-stage, cervical carcinoma.

BACKGROUND: The objective of this study was to compare survival between patients with adenocarcinoma and patients with adenosquamous carcinoma of the cervix. METHODS: Patients who were diagnosed with invasive cervical carcinoma from 1988 to 1999 were identified from the Automated Central Tumor Registry for the United States Military Health Care System. Clinical data, including race, age at diagnosis, histology, tumor grade, disease stage, lymph node status, treatment modality, and survival, were collected. Survival analysis was performed with Kaplan-Meier survival curves and compared using the log-rank test. RESULTS: A total of 273 women were identified, 185 women with a histologic diagnosis of adenocarcinoma (AC) and 88 women with a diagnosis of adenosquamous carcinoma (ASC). Among the women with ASC, only 5% had Grade 1 tumors, and 66% had Grade 3 tumors. By comparison, among the women with AC, 37% had Grade 1 tumors, and 26% had Grade 3 tumors (P < 0.001). There was no difference in the incidence of positive lymph nodes or in the number of patients who underwent radical hysterectomy as primary treatment between patients with ASC and patients with AC. More patients with ASC received radiation therapy (51% vs. 28%) or chemotherapy (29% vs. 12%) as treatment (P < 0.001). Patients who had tumors with ASC histology had a significantly decreased 5-year survival rate compared with patients who had tumors with AC histology (65% vs. 83%; P < 0.002). When patients with early-stage cervical carcinoma (International Federation of Gynecology and Obstetrics [FIGO] Stage I) were examined separately, there was no statistically significant difference in the 5-year survival rate (AC, 89%; ASC, 86%; P = 0.644). However, when patients with advanced-stage disease (FIGO Stages II-IV) were analyzed, ASC was associated with a significant decrease in median and overall survival (P = 0.01). When the results were analyzed by grade, patients who had tumors with ASC histology had a shorter survival compared with patients who had AC histology of any grade; however, this was a significant difference only for patients with Grade 1 tumors: The 5-year survival rate for patients with Grade 1 AC was 93%, compared with 50% for patients with Grade 1 ASC (P < 0.01). CONCLUSIONS: ASC histology appears to be an independent predictor of poor outcome in women with cervical carcinoma compared with their counterparts who have pure AC. The significant decrease in survival was observed only in patients with advanced-stage cervical carcinoma. This decreased survival may be related mainly to the grade of ASC.

Adenocarcinoma↗

PubMed1993

Ascorbic acid inhibition of cytochrome P450-catalyzed uroporphyrin accumulation.

Previous studies on the mechanism of the uroporphyria caused by polyhalogenated aromatic hydrocarbons have indicated a key role of cytochrome P450 of the 1A subfamily in catalyzing uroporphyrinogen (UROgen) oxidation. Here we report that ascorbic acid (ASC) inhibits UROgen oxidation in primary cultures of chick embryo hepatocytes and hepatic microsomes from chickens and mice. In hepatocyte cultures, 0.15 mM ASC totally prevented the accumulation of uroporphyrin (URO) induced by treatment of cells with the combination of 3,4,3',4'-tetrachlorobiphenyl (TCB) and 2-propyl-2-isopropylacetamide (PIA), but had no effect on the induction of protoporphyrin accumulation by PIA and desferrioxamine. However, addition of 5-aminolevulinic acid (ALA) to cultures treated with PIA plus TCB decreased the ability of ASC to prevent URO accumulation, suggesting that the effectiveness of ASC was dependent on the intracellular concentration of ALA or its metabolites. Similarly, when chick hepatocyte cultures were treated with TCB plus exogenous ALA to produce URO accumulation, the effectiveness of ASC was also less than when ALA was produced endogenously. Under this condition, addition of piperonyl butoxide, a P450 inhibitor, increased ASC inhibition of URO accumulation. ASC competitively inhibited the oxidation of UROgen by hepatic microsomes from chicks or mice treated with 3-methylcholanthrene (MC) with Ki for ASC being about 0.1 mM. ASC prevented formation of a 500-nm absorbing compound, probably tetrahydrouroporphyrin, the first intermediate in UROgen oxidation. These results are consistent with ASC preventing URO accumulation in hepatocytes by competitive inhibition of the first step of UROgen oxidation and suggest a new physiological role of ASC, that of maintaining UROgen in the reduced state.

Animals↗

PubMed1995

Enumeration of isotype-specific antibody-secreting cells derived from gnotobiotic piglets inoculated with porcine rotaviruses.

In order to evaluate mucosal antibody responses to rotavirus, an enzyme-linked immunospot (ELISPOT) assay was adapted to enumerate antibody-secreting cells (ASC) in the mesenteric lymph nodes (MLN), lamina propria (LP) of the small intestine and spleens of gnotobiotic pigs orally inoculated with porcine rotaviruses (SB1A and Gottfried). Rotavirus-specific IgM ASC occurred by post-inoculation day (PID) 3, and numbers peaked in spleen and MLN tissues by PID 7 and in intestinal LP by PID 7-14. Numbers of rotavirus specific IgA and IgG ASC in these tissues peaked at PID 14-21. Rotavirus specific IgA ASC were predominant in the gut and IgA to IgG rotavirus specific ASC ratios were highest for all rotavirus antigen coatings in the gut LP. However, the relative ratios of specific IgA to IgG ASC were lower (ratios of 5 to 7) against combined structural and nonstructural viral antigens (rotavirus-infected fixed cell ELISPOT plates) than ratios (13 to 46) against only viral structural antigens (rotavirus-coated ELISPOT plates), indicating that there were proportionately more specific IgG ASC to the nonstructural viral antigens in the LP, the tissue adjacent to the site of rotavirus replication in the intestine. In the node cells (spleen and MLN) rotavirus-specific IgA to IgG ASC ratios were lowest and against the various ELISPOT rotavirus coatings ranged from 0.7 to 4. Gnotobiotic piglets inoculated at different ages with porcine rotaviruses generally showed similar specific immunoglobulin (Ig) ASC responses to rotavirus infection, along with similar diarrhea and virus shedding patterns in the different age groups. However, the numbers of specific IgA ASC in the MLN of 3-4 week old pigs were higher than those of 3-5 day old pigs. Although challenge of SB1A or Gottfried rotavirus-inoculated pigs with SB1A (G4P7) or Gottfried (G4P6) rotavirus revealed a high degree of protection from diarrhea and virus shedding, greater numbers of specific IgM ASC were observed in spleen after challenge of SB1A-inoculated pigs with Gottfried rotavirus (same G type, distinct P type). Thus, by using the ELISPOT technique, we successfully measured intestinal mucosal antibody-related responses to rotavirus in gnotobiotic pigs. Moreover, our results support the use of gnotobiotic piglets as an animal model to evaluate active antibody responses and protection against rotavirus infection and disease.

Animals↗

PubMed2005

Abdominal sacral suspensions: analysis of complications using permanent mesh.

OBJECTIVE: This study was undertaken to determine the complication rates of abdominal sacral suspensions (ASC) using polypropylene mesh and to compare the erosion rates in women who underwent ASC at the time of supracervical hysterectomy (SCH) versus total abdominal hysterectomy (TAH) versus ASC in women who had previously undergone TAH. STUDY DESIGN: A retrospective analysis of patients from the urogynecology practice at North Shore University Hospital, who underwent ASC with polypropylene mesh between March 1997 and July 2004. Office and hospital charts were reviewed for patient demographics, preoperative history and physical examinations, intraoperative and postoperative findings, and complications. Women were stratified into 3 groups: group I: SCH with ASC; group II: TAH with ASC; and group III: ASC alone in women with a history of prior TAH. RESULTS: A total of 121 patients were analyzed and comprised group I, 30.6% (n = 37); group II, 40.5% (n = 49); and group III, 28.9% (n = 35). Four patients (3.3%) had mesh erosions develop. There were no significant differences in age, weight, parity, menopause status, estrogen therapy, previous surgery, or degree of preoperative prolapse between the patients with and without erosions. All the erosions occurred in group II (8.2%, 95% CI (2.3%-19.6%, P = .0389). The intraoperative complication rate was 2.5% and included a cystotomy (n = 2) and a small bowel laceration (n = 1). Immediate postoperative complications included partial SBO/ Ileus (3.5%), febrile morbidity (9.6%), and autologous blood transfusions (1.7%). Long-term complications included persistent vaginal discharge (4.7%), vaginal bleeding (1.6%), dysparuenia (6.3%), and recurrent prolapse (2.5%). There were no significant differences in short- or long-term complications among the 3 groups (P > .05). CONCLUSION: ASC with polypropylene mesh is a safe surgical procedure for vaginal vault prolapse with low complication rates. Mesh erosion occurred in 8.2% of patients who underwent TAH with concurrent ASC. Patients having ASC at the time of TAH had a 7-fold increased risk for mesh erosion compared with patients who underwent SCH with ASC.

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