Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anticardiolipin antibodies (ACA) frequently appear in patients with autoimmune disorders such as systemic lupus erythematosus, and have also been detected in infections, neoplasia, the primary antiphospholipid syndrome, in association with certain medications and also in those patients without apparent disease. Recently, anticardiolipin antibodies were described in connection with acquired immunodeficiency syndrome (AIDS). 84 human immunodeficiency virus (HIV)-infected patients were examined in order to assess the influence of risk factors for HIV infection and of the stage of HIV-1 infection on the prevalence of IgG-ACA in HIV-seropositive patients. 2 groups were created -- 1 composed of 38 asymptomatic HIV-infected individuals and the other of 46 AIDS patients. A control group of 42 healthy HIV-negative blood donors was also studied. All those in the control group were IgG-ACA-negative. Of the 84 HIV-positive patients, 50 were IgG-ACA positive (59.5%) and 34 IgG-ACA-negative (40.5%). None of the HIV-positive individuals presented any thromboembolic phenomena. There were no significant differences with respect to sex, risk factors, and stage of disease when the presence of IgG-ACA in HIV-positive patients was ascertained. ACA does not appear to be a prognostic marker in HIV-1 infected patients; the presence of IgG-ACA is probably related to HIV-1 infection itself and is indicative of impaired humoral immunity in this group. (author's modified)
Infection
PMID:Anticardiolipin antibodies and acquired immunodeficiency syndrome: prognostic marker or association with HIV infection? 164 88

Human papillomaviruses are a heterogeneous group of DNA tumor viruses associated with hyperplastic (warts, condylomata), dysplastic (CIN and VIN), and malignant lesions (carcinomas) of squamous epithelium. Each HPV type is preferentially associated with specific clinical lesions and has an anatomic site preference for either cutaneous or mucosal squamous epithelium. Infection appears to begin in the basal cells. Early gene expression is associated with acanthosis, and late gene expression is associated with appearance of structural antigens and virions in nuclei of cells of the granular layer, usually koilocytotic cells. Malignant transformation of warts and papillomas appears to be related to a variety of factors: (1) infection by certain HPV types (HPV-5, HPV-8, HPV-16, HPV-18, HPV-31); (2) decreased cellular immunity to HPV-associated antigens; and (3) interaction with cofactors such as other microorganisms or sunlight. Spontaneous regression or successful treatment of the benign lesions appears to depend on either naturally acquired or iatrogenically related stimulation of HPV type-specific immunity. The humoral antibody response to HPV particles may be important in preventing infection. In contrast, the local events surrounding regression of warts and condylomata are primarily associated with specific cell-mediated immunity. Local cell-mediated immune responses, particularly cell-associated soluble mediators and stationary macrophage-like cells, may be especially important in the host's immune response to mucosal infections.
 ...
PMID:Tissue effects of and host response to human papillomavirus infection. 164

Infection of normal human diploid fibroblasts (HF) with the DNA tumor virus simian virus 40 (SV) leads to an extension of lifespan and concomitant increase in the levels of the viral large tumor antigen (T antigen) and the cellular protein p53. The intracellular localization of T antigen and p53 was mostly nuclear in both SVpre-crisis and SVpost-crisis cells, however certain population doubling (PD) of the SVpre-crisis cells exhibited some cytoplasmic staining. The DNA content of SVpre-crisis cells shifted to tetraploidy and the SVpost-crisis cells were near-tetraploid. Quantitation of T antigen and p53 in single cells by flow cytometry demonstrated that for all antibodies tested the levels of T antigen were higher in the SVpre-crisis HF than in the SVpost-crisis. The quantity of p53 increased with increasing age of SVpre-crisis HF, and the levels of p53 were higher in the SVpost-crisis HF populations. Immunoprecipitation of p53, T antigen and complexes demonstrated that all p53 was bound to T antigen in SVpre-crisis HF and SVpost-crisis HF. The SVpre-crisis HF cells showed that 33% of all T antigen was bound to p53, while 67% was free, and the SVpost-crisis HF exhibited 50% free T antigen and 50% bound to p53. The half-life of p53 was similar in all SVpre-crisis HF; however, the half-life was 2-3 times greater in SVpost-crisis HF than in SVpre-crisis HF. These results suggest that the interaction of DNA (ploidy), T antigen, p53 and complexes may be involved in formation of a stable SV40-transformed human cell line.
 ...
PMID:T antigen and p53 in pre- and post-crisis simian virus 40-transformed human cell lines. 165 67

Infection of quiescent BALB/c 3T3 cells with polyomavirus leads to the biphasic accumulation of RNA from several early-response genes. The steady-state levels of RNA of c-fos, c-myc, and c-jun were detected at 0 to 1 and 12 to 30 h after infection but not at 6 h postinfection. Infections with mutant viruses suggest that in the context of a virus infection with other tumor (T) antigens present, large T and middle T antigens are dispensable for the effect and small t antigen is important for the regulation, perhaps in conjunction with large T or middle T antigens. These results are in agreement with those of Zullo et al. (Proc. Natl. Acad. Sci. USA 84:1210-1214). We have further found that this regulation occurs in NIH 3T3 cells and primary mouse embryo fibroblasts. DNA synthesis is not required for this effect. Half-lives of c-fos, c-myc, and c-jun were similarly short at both early and late times after infection, as determined by dactinomycin chase. The regulation of expression occurs at the transcriptional level. Nuclear run-on experiments showed increased rates of transcription both early and late after infection. Also, the polyomavirus early region can transactivate the c-fos promoter in transient transfection assays.
 ...
PMID:Transcriptional regulation of early-response genes during polyomavirus infection. 169 11

Infection of 1-day-old chicks with reticuloendotheliosis virus strain T induces a neoplastic disease that kills the chicks 7 to 14 days postinfection. In association with reticuloendotheliosis-associated virus (REV-A), reticuloendotheliosis virus T (REV-T) induces tumors that are predominantly immunoglobulin M (IgM) negative. We examined a variety of REV-T(REV-A)-induced tumors and tumor-derived cell lines and concluded that the principal IgM-negative tumors that develop in REV-T(REV-A)-infected chicks are neither pre-B or pre-B-pre-T but rather mature T lymphoid and myeloid. Without exception, the immunoglobulin heavy- and light-chain loci were in germ line configuration. Furthermore, the cell lines expressed neither sterile transcripts of the heavy- or light-chain immunoglobulin genes nor elevated levels of c-myb, two characteristics associated with murine pre-B lymphomas. Cell lines were also examined by using monoclonal antibodies for expression of a variety of cell surface markers expressed on B lymphocytes and/or T lymphocytes and/or myeloid cells. These reagents defined two types of IgM-negative tumor cell lines, one CIa+ CT-3+ (T lymphoid) and the other CIa+ CT-3-. By using the same approaches, tumor development was examined following REV-T(REV-A) infection at 1 and 3 weeks post-hatching of cyclophosphamide-treated chicks shown to be devoid of B-lymphoid cells. Again, the tumors that developed were either CIa+ CT-3+ (T lymphoid) or CIa+ CT-3-. Furthermore, the frequency and rate with which IgM-negative tumors developed in cyclophosphamide-treated chicks were not different from those observed in normal chicks. In 3-week-old cyclophosphamide-treated chicks, the presence of CIa+ CT-3- tumors bearing hematopoietic lineage markers, such as CLA-3 and 5M19, are most likely to have been derived from cells within the myeloid lineage.
 ...
PMID:Reticuloendotheliosis virus REV-T(REV-A)-induced neoplasia: development of tumors within the T-lymphoid and myeloid lineages. 170 Aug 31

Four plasma proteins, referred to as positive acute phase proteins because of increases in concentration following inflammatory stimuli, are reviewed: C-reactive protein (CRP), serum amyloid A protein (SAA), alpha 1-acid glycoprotein (AAG), and fibrinogen. The CRP and SAA may increase in concentration as much as 1000-fold, the AAG and fibrinogen approximately twofold to fourfold. All are synthesized mainly in the liver, but each may be produced in a number of extrahepatic sites. The role of cytokines in induction of the acute phase proteins is discussed, particularly the multiple functional capabilities of interleukin-6 (IL-6). Other cytokines that regulate acute phase gene expression and protein synthesis include IL-1, tumor necrosis factor alpha, interferon gamma, as well as other stimulatory factors and cofactors. The physicochemical characteristics of each protein are reviewed together with the molecular biology. For each protein, the known biological effects are detailed. The following functions for CRP have been described: reaction with cell surface receptors resulting in opsonization, enhanced phagocytosis, and passive protection; activation of the classical complement pathway; scavenger for chromatin fragments; inhibition of growth and/or metastases of tumor cells; modulation of polymorphonuclear function; and a few additional diverse activities. The role of plasma SAA is described as a precursor of protein AA in secondary amyloidosis; other functions are speculative. AAG may play an immunoregulatory role as well as a role in binding a number of diverse drugs. In addition to clot formation, new data are described for binding of fibrinogen and fibrin to complement receptor type 3. Finally, the concentration of each protein is discussed in a wide variety of noninfectious and infectious disease states, particularly in connective tissue diseases. The quantification of the proteins during the course of various acute and chronic inflammatory disorders is useful in diagnosis, therapy, and in some cases, prognosis.
 ...
PMID:Properties of four acute phase proteins: C-reactive protein, serum amyloid A protein, alpha 1-acid glycoprotein, and fibrinogen. 170 51

When defined in terms of markers for normal cell lineages, most invasive breast cancer cells correspond to the phenotype of the common luminal epithelial cell found in the terminal ductal lobular units. Luminal epithelial cells cultured from milk, which have limited proliferative potential, have now been immortalized by introducing the gene encoding simian virus 40 large tumor (T) antigen. Infection with a recombinant retrovirus proved to be 50-100 times more efficient than calcium phosphate transfection, and of the 17 cell lines isolated, only 5 passed through a crisis period as characterized by cessation of growth. When characterized by immunohistochemical staining with monoclonal antibodies, 14 lines showed features of luminal epithelial cells and of these, 7 resembled the common luminal epithelial cell type in the profile of keratins expressed. These cells express keratins 7, 8, 18, and 19 homogeneously and do not express keratin 14 or vimentin; a polymorphic epithelial mucin produced in vivo by luminal cells is expressed heterogeneously and the pattern of fibronectin staining is punctate. Although the cell lines have a reduced requirement for added growth factors, they do not grow in agar or produce tumors in the nude mouse. When the v-Ha-ras oncogene was introduced into two of the cell lines by using a recombinant retrovirus, most of the selected clones senesced, but one entered crisis and emerged after 3 months as a tumorigenic cell line.
 ...
PMID:Efficient immortalization of luminal epithelial cells from human mammary gland by introduction of simian virus 40 large tumor antigen with a recombinant retrovirus. 170 84

Biotechnology has been fundamental to exploration and manipulation of life structures and processes at the molecular level. Regulation of expression of specific genes has impacted on understanding of cancer development and immunopathologic diseases. An even greater impact has been the production of new therapeutic molecules. Cytokines have been produced by recombinant DNA technology and are established as effective therapeutic modalities for cancer and infectious diseases. High quality pharmaceutical molecules have been produced which can substantially regulate cell function. Interferons typify this progress and are now licensed for both viral and neoplastic disease in more than 43 countries around the world. It seems certain that by the year 2000, the impact of biotechnology on human medicine will even be wider than that of today. Findings of biotechnology will have implications not only for advancement of human health but also will create debate regarding appropriate use.
 ...
PMID:Biotechnology: its impact on medicine and oncology. 171 79

We present an outline of the complex interplay of oxidants and antioxidants in infectious diseases in general, and in particular with reference to the HIV infection, and subsequent opportunistic infections. Viral and opportunistic infections may directly or indirectly cause an imbalance in prooxidant/antioxidant mechanisms and result in generation of increased steady state concentrations of reactive oxidants. In HIV patients a prooxidant state could lead to a self-perpetuation of infection via stimulated expression of genes carrying the virus genome, and subsequently to immunosuppression, and promotion of initiated cells to neoplastic growth.
 ...
PMID:Oxidative imbalance in HIV infected patients. 176 17

The classical basic concept of the immune system as a defence system per se and immunological surveillance against neoplasia have never been satisfactorily verified experimentally. The reason for this lies in the historic development of immunology in terms of observations of infectious disease and the interpretation of those observations. Thus, based on a complete lack of understanding of immune events, immunization procedures were developed by Pasteur and his contemporaries. The success of some of these immunization methods, influenced by culture and philosophical thoughts, and based on prima facie evidence allowed the next conceptual step to be taken, culminating in the immune surveillance hypothesis. Central to this hypothesis is selection and tolerance to self-antigens. However, immune reactions to self-antigens are evident and clonal selection is not viable because the number of clones required increases as the frequency of chance of a cell belonging to a particular clone decreases. Also, circadian rhythms in the immune response have not been taken into account. In addition, the problems of haemocytopoiesis have not been addressed, in that it is possible for B-lymphocytes to become terminal macrophages and T-lymphocytes to become mast cells, eosinophils and/or basophils constituting 'dead end' cells in an immune response. The initiation of the immune response begins with a tissue-specific T-lymphocyte being stimulated and undergoes replication. This gives rise to a dual functional helper/suppressor cell and a B-lymphocyte. These basic concepts explain the necessity for auto-reactive lymphocytes, that is the autologous mixed lymphocyte reaction (AMR). The AMR is a natural consequence of having tissue-specific lymphocytes to monitor plasma membrane aberrations.
 ...
PMID:Immune response: self-foreignness. 176 19


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>