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PubMed1998

HIV-1 antigen-specific and -nonspecific B cell responses are sensitive to combination antiretroviral therapy.

We studied how combination antiviral therapy affects B cell abnormalities associated with HIV-1 infection, namely elevated circulating immunoglobulin (Ig)G antibody-secreting cell (ASC) frequencies and hypergammaglobulinemia. Within a few weeks of starting antiviral therapy, there is a marked decline in IgG-ASC frequency in both acutely and chronically infected people, whereas the hypergammaglobulinemia often present during chronic infection is more gradually resolved. These reductions are sustained while HIV-1 replication is suppressed. HIV-1 antigen-specific B cell responses are also affected by therapy, manifested by a rapid decline in circulating gp120-specific ASCs. Anti-gp120 titers slowly decrease in chronically infected individuals and usually fail to mature in acutely infected individuals who were promptly treated with antiretroviral therapy. Long-term nonprogressors have high titer antibody responses to HIV-1 antigens, but no detectable gp120-specific IgG-ASC, and normal (or subnormal) levels of total circulating IgG-ASC. Overall, we conclude that HIV-1 infection drives B cell hyperactivity, and that this polyclonal activation is rapidly responsive to decreases in viral replication caused by combination antiviral therapy.

Antiviral Agents↗

PubMed1989

ELISPOT: a new approach to studying the dynamics of virus-immune system interaction for diagnosis and monitoring of HIV infection.

A new approach to detect and enumerate HIV-specific antibody-secreting cells (ASC) in the peripheral blood was developed using the enzyme-linked immunospot (ELISPOT) methodology. ASC to an HIV envelope recombinant protein were demonstrated in 75% of 16 adults and 72% of 21 children with untreated AIDS or ARC and in 63% of 34 asymptomatically infected adults but in none of the 51 HIV antibody-negative individuals. Only 1 of the 13 adults receiving AZT therapy yielded a positive reaction, and 27% of the 30 infants born to seropositive mothers were found to have HIV-ASC. The number of HIV-ASC in positive individuals varied from 8 to 202 per 10(6) circulating mononuclear cells. The reactivity was specifically inhibited by soluble HIV antigen and was abrogated by cycloheximide, indicating that the observed reaction was the result of de novo synthesis of HIV-specific antibodies. Nonspecific polyclonal B cell activation was unlikely to be responsible for the results observed as no reactivity was found to a common antigen, tetanus toxoid. Since circulating antigen-specific ASC reflect persistent or recent antigenic stimulation, our findings indicate that this new approach could provide a dynamic perspective of the natural course of virus-immune system interactions in individuals infected with HIV, as well as in those undergoing prophylactic or therapeutic interventions.

AIDS-Related Complex↗

PubMed1998

Research notes: ELISPOT assay for detection of antibody secreting cells to infectious bursal disease virus in chickens.

The ELISPOT assay was used to enumerate antibody secreting cells (ASC) in spleens of chickens infected with infectious bursal disease virus (IBDV). In the first experiment, chickens were orally challenged with IBDV. Spleens were collected 14 d later and used for ELISPOT assay. The assay detected 16 to 28 IgG ASC per 10(6) splenocytes and 3 to 6 IgM ASC per 10(6) splenocytes. In the second experiment, chickens were vaccinated against IBDV and orally challenged with IBDV 14 d after vaccination. Spleens were collected 7 d postchallenge. The ELISPOT assay detected 18 to 128 IgG ASC per 10(6) splenocytes and 4 to 6 IgM ASC per 10(6) splenocytes. The results indicated that the ELISPOT assay can be used to measure isotype-specific antibody responses to IBDV or other avian pathogens.

Animals↗

PubMed2005

The polysaccharide antibody response after Streptococcus pneumoniae vaccination is differentially enhanced or suppressed by 3,4-dichloropropionanilide and 2,4-dichlorophenoxyacetic acid.

Propanil (3,4-dichloropropionanilide) and 2,4-D (2,4-dichlorophenoxyacetic acid) are commonly used herbicides that have toxic effects on the immune system. The present study determined the effect of exposure to these chemicals on the immune response to a bacterial vaccine. The antibody responses to the T-independent type 2 antigen, phosphorylcholine (PC) and the T-dependent antigen, pneumococcal surface protein A (PspA) were characterized in C57BL/6 mice after heat-killed Streptococcus pneumoniae (HKSP) immunization and single or mixture herbicide exposure. Propanil exposure significantly increased the number of PC-specific IgM, IgG2b, and IgG3 antibody-secreting B cells (ASC) in the spleen 4-6-fold over control animals in a dose-dependent manner. However, the number of ASC in the bone marrow and serum titers were comparable in control and propanil-treated mice. In contrast, 2,4-D exposure decreased the number of PC-specific IgM and IgG bone marrow ASC 2-3-fold from control animals. The decrease in bone marrow ASC in 2,4-D-treated mice corresponded to a 3-4-fold decrease in PC-specific IgM, IgG2b, and IgG3 serum titers compared to control mice. The number of ASC in the spleens of 2,4-D-treated mice was, however, comparable to control mice. The antibody response to PspA was not affected by any of the treatments. There were no mixture interactions between the two herbicides in any of the responses measured. These results characterize the primary PC-specific antibody response in the bone marrow, spleen, and serum after HKSP vaccination and herbicide exposure. The differential effects of propanil and 2,4-D on the antibody response to a bacterial vaccine demonstrate the potential of chemical exposure to augment or suppress immune responses to vaccines and infectious diseases.

2,4-Dichlorophenoxyacetic Acid↗

PubMed1992

Ultrastructural effect of L-ascorbic acid 2-phosphate on cultured keratocytes.

I studied the effect of L-ascorbic acid 2-phosphate (P-Asc), a long-acting derivative of L-ascorbic acid, on the fine structures of cultured rabbit keratocytes. The results showed that cells cultured with 0.1 mM P-Asc for 30 days were more markedly multilayered than those grown without P-Asc. Dilation of the cisternae of the endoplasmic reticulum in the control cells indicated an accumulation of protein (probably procollagen). In addition, many lysosome-like structures, which may degrade underhydroxylated procollagen, were observed in the cytoplasm of the control cells. A slight increment of free ribosomes was also found within the control cells. P-Asc enhanced the multilayerization of cultured keratocytes. We conclude that the changes seen in the cytoplasm are due to the effect of P-Asc acting as vitamin C.

Animals↗

PubMed1992

Correlation of abdominal trauma index and injury severity score with abdominal septic complications in penetrating and blunt trauma.

The Abdominal Trauma Index (ATI) was designed to stratify patients with penetrating injuries, and has been used to classify patients with blunt trauma. The Injury Severity Score (ISS) was originally designed to stratify victims of blunt trauma, and it has also been used for victims of penetrating trauma. We attempted to validate the use of ISS and ATI for both penetrating and blunt trauma. A total of 592 penetrating and 334 blunt trauma patients who underwent laparotomy over a 5-year period were evaluated. The overall rate of abdominal sepsis was 7.5% for blunt trauma and 7.6% for penetrating trauma. Mortality (excluding deaths within 48 hours) was 7% for blunt trauma and 1% for penetrating trauma. In the penetrating injury population, an ATI value greater than 15 and an ATI value greater than 25 were significantly associated with abdominal septic complications (ASCs) (p less than 0.001, both comparisons). An ISS greater than or equal to 16 was also associated with ASCs (p less than 0.001). The ASC rate for gunshots was higher than that for stab wounds (11% vs. 2%; p less than 0.001). In the blunt group, an ATI value greater than 15 and an ATI value greater than 25 were associated with ASCs (p less than 0.01 and p less than 0.001, respectively). The association of ASCs and ISS was linear with increasing ISS in patients with blunt abdominal trauma.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Injuries↗

PubMedDate not supplied

Subjective symptomatology of asthma in an outpatient population.

Characteristics of subjective symptomatology of asthma were examined within a group of 132 adult asthma patients receiving medical care in a university-based, ambulatory clinic setting. Patients responded to 36 symptom descriptions or adjectives associated with asthma which were included in a modified version of the Asthma Symptoms Checklist (ASC). A principal components exploratory factor analysis was conducted and five factors were identified. The five factors measured 1) panic-fear, 2) airways obstruction, 3) hyperventilation, 4) fatigue, and 5) irritability. Psychometric properties of the factor scores were satisfactory. The reliabilities were high, standard deviations were large, and differences in factor mean scores conformed to clinical experience. Correlational analyses support the construct validity of the ASC, especially the panic-fear factor. An important outcome of this study was to verify the ASC factor structure in an outpatient setting. The ASC was confirmed as a valuable instrument for use in self-management programs for adults with asthma. The five ASC factors represent highly stable components of subjective symptomatology of asthma among diverse adult patient populations and geographical settings.

Adaptation, Psychological↗

PubMed1999

Enzyme-linked immunospot assay for the diagnosis of active Treponema pallidum infection during the various stages of syphilis.

BACKGROUND: Specific serologic assays for syphilis cannot differentiate current infections from past infections and are inefficient to monitor efficacy of antibiotic therapy. GOAL: To develop a new immunologic assay for the identification of active Treponema pallidum infection during the various stages of syphilis. STUDY DESIGN: Peripheral blood mononuclear cells obtained from patients with syphilis in an STD clinic were tested for T. pallidum-specific circulating antibody-secreting cells (ASC) by an enzyme-linked immunospot assay (ELISPOT). RESULTS: Specific ASC were demonstrated in all six patients with primary syphilis and in 14 of 16 patients diagnosed with secondary syphilis. ASCs were undetectable in five patients 8 to 16 days after appropriate therapy, but persisted in one case that was considered treatment failure. Among the 13 patients diagnosed with latent syphilis, six (46%) demonstrated ASC, reflecting antigenic stimulation. CONCLUSION: The ELISPOT assay is effective for the diagnosis of primary and secondary syphilis. The presence of circulating ASC suggests persistent active infection in some patients during the latent disease stage.

Adolescent↗

PubMedDate not supplied

Inhibition by analogues of L-tyrosine transport by B16/F10 melanoma cells.

The effect of a number of L-tyrosine (L-Tyr) analogues on L-Tyr uptake by B16/F10 malignant melanocytes is reported. This amino acid can be taken up by two of the most ubiquitous transport systems found in animals cells, L and presumably ASC. L-Tyr analogues devoid of the amino group, like p-hydroxyphenyl pyruvic acid and related compounds, and L-Tyr analogues devoid of the carboxyl group, such as tyramine, do not affect L-Tyr uptake. The other aromatic amino acids, L-Phe and L-Trp, and the L-Tyr analogues DL-m-Tyr, L-diiodotyrosine and L-dopa, strongly inhibit the uptake of L-Tyr. This suggests that these chemicals are transported more efficiently than L-Tyr. The ASC system does not show stereospecificity, but the L system has greater affinity for L-Tyr than for D-Tyr. The ASC system also has greater affinity for tyrosine isomers with the hydroxyl group in the ortho and meta positions. The presence of a methyl group at the alpha-carbon of L-Tyr and L-dopa also increases the affinity of the ASC system for these agents. In contrast, alpha-methylation decreases the affinity of the L system in comparison to L-Tyr. Finally, L-Tyr esters do not inhibit, but stimulate the transport of L-Tyr, mainly by the ASC system.

Amino Acid Transport Systems↗

PubMed2001

Which side effects really matter? Screening for common and distressing side effects of antipsychotic medications.

As a class, the newer antipsychotics are less likely to cause EPS but continue to have a range of other, non-EPS, side effects. Most standardized scales for side effects of antipsychotics emphasize the physical findings of the motor abnormalities of extrapyramidal symptoms (EPS). There is a need for screening instruments that include both EPS and non-EPS side effects. This article discusses the development of a screening instrument called the Approaches to Schizophrenia Communication (ASC). Initially derived from other subjective screening measures, the ASC was specifically designed to address the following issues pertaining to side effect evaluation of antipsychotics: 1) to cover all common and distressing side effects from antipsychotics, not just EPS, and 2) to screen for perceived distress, rather than the objective severity of the side effect. These two characteristics of the ASC make it possible for it to be given directly to the patient (the ASC Self-Report Version) or to be administered by mental health clinicians who do not have to be extensively trained in side-effect assessments (the ASC Clinician Interview version).

Journal Article↗

PubMed2001

Antioxidant systems and O(2)(.-)/H(2)O(2) production in the apoplast of pea leaves. Its relation with salt-induced necrotic lesions in minor veins.

The present work describes, for the first time, the changes that take place in the leaf apoplastic antioxidant defenses in response to NaCl stress in two pea (Pisum sativum) cultivars (cv Lincoln and cv Puget) showing different degrees of sensitivity to high NaCl concentrations. The results showed that only superoxide dismutase, and probably dehydroascorbate reductase (DHAR), were present in the leaf apoplastic space, whereas ascorbate (ASC) peroxidase, monodehydroascorbate reductase (MDHAR), and glutathione (GSH) reductase (GR) seemed to be absent. Both ASC and GSH were detected in the leaf apoplastic space and although their absolute levels did not change in response to salt stress, the ASC/dehydroascorbate and GSH to GSH oxidized form ratios decreased progressively with the severity of the stress. Apoplastic superoxide dismutase activity was induced in NaCl-treated pea cv Puget but decreased in NaCl-treated pea cv Lincoln. An increase in DHAR and GR and a decrease in ASC peroxidase, MDHAR, ASC, and GSH levels was observed in the symplast from NaCl-treated pea cv Lincoln, whereas in pea cv Puget an increase in DHAR, GR, and MDHAR occurred. The results suggest a strong interaction between both cell compartments in the control of the apoplastic ASC content in pea leaves. However, this anti-oxidative response does not seem to be sufficient to remove the harmful effects of high salinity. This finding is more evident in pea cv Lincoln, which is characterized by a greater inhibition of the growth response and by a higher rise in the apoplastic hydrogen peroxide content, O(2)(.-) production and thiobarbituric acid-reactive substances, and CO protein levels. This NaCl-induced oxidative stress in the apoplasts might be related to the appearance of highly localized O(2)(.-)/H(2)O(2)-induced necrotic lesions in the minor veins in NaCl-treated pea plants. It is possible that both the different anti-oxidative capacity and the NaCl-induced response in the apoplast and in the symplast from pea cv Puget in comparison with pea cv Lincoln contributes to a better protection of pea cv Puget against salt stress.

Adaptation, Physiological↗

PubMed2003

Zonal changes in ascorbate and hydrogen peroxide contents, peroxidase, and ascorbate-related enzyme activities in onion roots.

Onion (Allium cepa) roots growing hydroponically show differential zonal values for intra- (symplastic) and extra- (apoplastic) cellular ascorbate (ASC) and dehydroascorbate (DHA) contents and for related enzyme activities. In whole roots, ASC and DHA concentrations were higher in root apex and meristem and gradually decreased toward the root base. Guaiacol peroxidase, ASC peroxidase, monodehydroascorbate oxidoreductase, DHA reductase, catalase, and glutathione reductase activities showed differential activity patterns depending on the zone of the root and their apoplastic or symplastic origin. An in vivo staining of peroxidase activity also revealed a specific distribution pattern along the root axis. Using electron microscopy, hydrogen peroxide was found at different locations depending on the root zone but was mainly located in cell walls from epidermal and meristematic cells and in cells undergoing lignification. A balanced control of all of these molecules seems to exist along the root axis and may be directly related to the mechanisms in which the ASC system is involved, as cell division and elongation. The role of ASC on growth and development in relation to its presence at the different zones of the root is discussed.

Ascorbate Peroxidases↗

PubMed2006

Dehydroascorbate reductase affects leaf growth, development, and function.

Ascorbic acid (Asc) is a major antioxidant in plants that detoxifies reactive oxygen species (ROS) and maintains photosynthetic function. Expression of dehydroascorbate reductase (DHAR), responsible for regenerating Asc from an oxidized state, regulates the cellular Asc redox state, which in turn affects cell responsiveness and tolerance to environmental ROS. Because of its role in Asc recycling, we examined whether DHAR is important for plant growth. Suppression of DHAR expression resulted in a preferential loss of chlorophyll a, a lower steady state of Rubisco as measured by the amount of the large subunit of Rubisco (RbcL), and a lower rate of CO(2) assimilation. As a consequence, a slower rate of leaf expansion and reduced foliar dry weight were observed. In addition, an accelerated rate of loss of chlorophyll, RbcL, light-harvesting complex II, and photosynthetic functioning was observed in mature leaves, resulting in premature leaf aging. Reduced growth rate as measured by plant height and leaf number was consistent with the DHAR-mediated reduction of photosynthetic function. Increasing DHAR expression maintained higher levels of chlorophyll, RbcL, light-harvesting complex II, and photosynthetic functioning, resulting in delayed leaf aging. The effect of DHAR expression on leaf aging inversely correlated with the level of lipid peroxidation, indicating that DHAR functions to protect against ROS-mediated damage. These observations support the conclusion that through its Asc recycling function, DHAR affects the level of foliar ROS and photosynthetic activity during leaf development and as a consequence, influences the rate of plant growth and leaf aging.

Ascorbic Acid↗

PubMed1991

Functional characterization of SV40-transformed adherent synovial cells from rheumatoid arthritis.

A total of 14 transformed cell clones were obtained by micro-injecting origin-defective SV40 DNA into three types of cloned adherent synovial cells (ASC) (dendritic cells (DCs), macrophage-like cells (MCs), and fibroblast-like cells (FCs)) from two rheumatoid arthritis patients (five DC clones (SV40-DCs), five MC clones (SV40-MCs) and four FC clones (SV40-FCs)). All the transformed cell nuclei expressed SV40-specific T antigen. The cells which formed a colony had a few times shorter doubling time than the original cells. IL-1 alpha, IL-1 beta and prostaglandin E2 were detected in the culture supernatant from the unstimulated transformed cells like untransformed cells. The SV40-DCs showed the most potent accessory cell function in oxidative mitogenesis assay among the three types of SV40-ASCs. Granulocyte macrophage colony stimulatory factor (GM-CSF) was detected only in the culture supernatant from the SV40-MCs without stimulation. Extensive phenotypic analysis revealed relatively cell-specific markers. SV40-DCs were HLA-DP+ and glial fibrillary acidic protein positive. SV40-MCs stained positive for 5'-nucleotidase and nonspecific esterase. These transformed ASCs retained much of the original cellular physiology of rheumatoid arthritis (RA) ASCs and may be a useful tool for characterizing the role of ASCs in the pathogenesis of RA.

Adult↗

PubMed1991

Tissue distribution of mucosal antibody-producing cells specific for respiratory syncytial virus in severe combined immune deficiency (SCID) mice engrafted with human tonsils.

Groups of C.B-17 SCID mice were reconstituted intraperitoneally with human tonsillar mononuclear cells (hu-TMC) from children seropositive for antibody to respiratory syncytial virus (RSV) and subsequently challenged intraperitoneally with inactivated RSV or sham-immunized. The synthesis and the distribution characteristics of human antibody to RSV in various murine tissues were studied using an enzyme-linked immunospot assay (ELISPOT). No specific antibody was observed in sham-immunized animals. In contrast, mice engrafted with hu-TMC exhibited the appearance of specific human antibody secreting cells (hu-ASC) after i.p. immunization with inactivated RSV. RSV-specific hu-ASC were detected only in animals engrafted with cells from donors seropositive for antibodies to Epstein-Barr virus. Hu-TMC engrafted mice showed RSV-specific IgM and, in lower numbers, IgG hu-ASC in several tissues including the lungs. Numbers of RSV-specific IgA hu-ASC were low, however, and detected only in the lung. No RSV-specific hu-ASC were detected in the intestine. These data demonstrate for the first time that hu-TMC-SCID chimeras respond to immunization with viral antigen. Furthermore, the results suggest that hu-TMC engraft in lungs but not in the intestinal tissue.

Adolescent↗

PubMed2005

HPV triage of women with atypical squamous cells of undetermined significance: a 3-year experience in an Italian organized programme.

OBJECTIVE: The purpose of our study was to determine if Hybrid Capture II assay (HCII) on Liquid Based Cytology (LCB) improves the accuracy (higher sensitivity, similar specificity) than the repeat conventional Pap smear in smears with Atypical Squamous Cell (ASC) of Undetermined Significance diagnosis. METHODS: HPV testing was used to manage women, especially the older ones, with cervical abnormalities detected through our triennial organized screening in order to avoid unnecessary colposcopy and excessive follow-up if the woman is HPV negative. The HPV DNA Triage was offered without any charge to 909 women with ASC. The Bethesda System was used for the classification of these equivocal cytological findings and more precisely the 1991 version (ASCUS) until the summer 2001 (315 cases) and the new one 2001 classification (ASC-US and ASC-H) after this date (594 cases). The presence or absence of a cervical intraepithelial neoplasia of grade I or worse [CIN1+], and of grade II or worse [CIN2+], was confirmed by biopsy. RESULTS: The HPV DNA Triage showed a good accuracy (specificity over 94%, sensitivity of 37% and PPV for CIN2+ lesions around 30%). The higher values of ASC-H lesions (.462) for the sensitivity for CIN 2+ probably signify that this lesion is already a SIL. CONCLUSIONS: Our data were comparable with those recently published on the meta-analysis by Arbyn et al., confirming the promising approach of our guidelines for the treatment of these patients even in terms of Health Technology Assessment (HTA).

Adult↗

PubMed2004

Adenosquamous carcinoma of the head and neck: criteria for diagnosis in a study of 12 cases.

AIMS: Adenosquamous carcinoma (ASC) of the head and neck is an unusual neoplasm in which a general consensus with regard to diagnostic criteria has not yet been reached. In this study we report the clinicopathological results of 12 ASCs, with special attention to their histological and immunohistochemical characteristics in order to define this neoplasm more precisely. METHODS AND RESULTS: All the patients were male with a peak incidence in the sixth decade of life. The tumours were located most frequently in the larynx and oral cavity, followed by the nasal cavity and pharynx. ASCs had two distinct histological components. The most extensive one was an usual keratinizing squamous cell carcinoma, arising from the surface epithelium, where characteristically severe dysplasia or carcinoma in situ was found in all cases. The second component was an adenocarcinoma, usually displayed in the deepest areas of the tumour. Evidence of origin from salivary or seromucinous glands was not found. Immunohistochemical studies demonstrated in most cases positivity of glandular differentiated areas for carcinoembryonic antigen (CEA) (11/12), CK7 (9/12) and CAM5.2 (7/12), whereas the squamous cell component was unreactive or reacted only focally for these markers. High-molecular-weight cytokeratin 34BE12 was positive in both components and CK20 was always negative. All cases showed high expression of Ki67 antigen. Most of them had overexpression of p53 (8/12) and DNA aneuploidy (10/12). Fifty percent of patients with ASC died of disease after a mean period of 23 months (range 12-35 months). CONCLUSIONS: ASC of the head and neck is an aggressive neoplasm that originates in the surface epithelium of the upper respiratory tract. Severe dysplasia or carcinoma in situ is usually found and its recognition helps to make the diagnosis. In addition to mucin stains, positive immunoreactivity for CEA, CK7 and CAM5.2 helps to identify the glandular component.

Adult↗

PubMed2005

Adenoid basal carcinoma of the uterine cervix: report of two cases with reference to adenosquamous carcinoma.

Adenoid basal carcinoma (ABC) of the uterine cervix is a rare neoplasm with excellent prognosis. Differential diagnosis between ABC and an ABC-like lesion of adenosquamous cell carcinoma (ASC) of the cervix is important due to their contrasting prognosis. Reported herein are two cases of ABC that have been compared with seven ASC exhibiting ABC-like lesions from approximately 2600 resected uterine cervical malignancies diagnosed at Shikoku Cancer Center. The two ABC were incidentally found in the uterine cervix of 69-year-old and 59-year-old Japanese women due to cervical intraepithelial neoplasia grade 3 and to squamous cell carcinoma, respectively. The ABC consisted of infiltrating nests of basaloid cells with low nuclear atypia. The patients remained alive without recurrence for 9 years and 18 months, respectively. An ABC-like lesion was defined as basaloid cell nests simulating ABC, but with some features indicating malignant potential. However, the differential diagnosis was sometimes difficult because two of seven ABC-like lesions were originally diagnosed as ABC. Immunohistochemically, cytokeratin 7 was negative for the basaloid cells of two ABC, but positive for six of six ABC-like lesions of ASC, while cytokeratin 8 was positive for both ABC and ASC. This cytokeratin pattern might provide a good tool for distinguishing between ABC and an ABC-like lesion of ASC when the histological findings are equivocal.

Adult↗