Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0021051 (immunodeficiency)
71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of neuroblastoma cultures with N-methyl-D-aspartate (NMDA) or human immunodeficiency virus type 1 (HIV-1) coat protein, gp120, induces significant cytotoxic effects which are reduced by leupeptin, E-64, N-Ac-Leu-Leu-norleucinal (ALLnL) as well as by N-Ac-Leu-Leu-normethioninal (ALLnM) and this suggests that activation of the Ca(2+)-dependent protease, calpain, is involved. The cell death induced by NMDA and gp120 appears to be of the necrotic type; in fact, analysis of DNA fragmentation by flow cytometry or agarose gel electrophoresis failed to demonstrate signs of apoptosis, such as the presence of apoptotic bodies or internucleosomal cleavage. Similar negative results were also obtained by studying the nuclear morphology of the cells with Hoechst 33258 staining. Altogether the data indicate that neuroblastoma cell death induced by NMDA and gp120 is of the necrotic type and this implicates calpain protease.
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PMID:NMDA and HIV-1 coat protein, GP120, produce necrotic but not apoptotic cell death in human CHP100 neuroblastoma cultures via a mechanism involving calpain. 895 22

Nijmegen breakage syndrome is characterized by a variable T cell and B cell immunodeficiency, growth failure, and an increased risk of malignancy. It is inherited in an autosomal recessive manner and is biochemically related to ataxia-telangiectasia. Cells from a patient with Nijmegen breakage syndrome were unable to arrest cell cycle progression after exposure to ionizing radiation, and BrdU incorporation into newly synthesized DNA was uninhibited, demonstrating that these cells have an aberrant response to radiation exposure. Although gross chromosomal breakage was observed, dinucleotide repeat segments were stable over time, suggesting that other types of DNA stability were not affected. DNA-PK activity, which is mediated by a protein related to the ataxia-telangiectasia gene product and is intimately involved in DNA repair and VDJ recombination, was normal in cells from an NBS patient. Therefore, cells from patients with Nijmegen breakage syndrome have an abnormal response to radiation exposure similar to that seen in ataxia-telangiectasia.
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PMID:Cell cycle checkpoints and DNA repair in Nijmegen breakage syndrome. 900 41

We measured the cellular uptake of 125I-labeled full-length Tat (amino acids 1 to 86) (125I-Tat(1-86)) and 125I-Tat(1-72) (first exon) in human fetal astrocytes, neuroblastoma cells, and human fetal neurons and demonstrated that the uptake of 125I-Tat(1-72) without the second exon was much lower than that of 125I-Tat(1-86) (P < 0.01). This suggests an important role for the C-terminal region of Tat for its cellular uptake. 125I-Tat uptake could be inhibited by dextran sulfate and competitively inhibited by unlabeled Tat but not by overlapping 15-mer peptides, suggesting that Tat internalization is charge and conformationally dependent. Interestingly, one of 15-mer peptides, Tat(28-42), greatly enhanced 125I-Tat uptake. These findings are important for understanding the neuropathogenesis of human immunodeficiency virus type 1 infection and in the potential application of Tat for drug delivery to cells.
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PMID:Molecular determinants for cellular uptake of Tat protein of human immunodeficiency virus type 1 in brain cells. 903 89

Interest in umbilical cord blood as an alternate source of hematopoietic stem cells is growing rapidly. Umbilical cord blood offers the clinician a source of hematopoietic stem cells that is rarely contaminated by latent viruses and is readily available. Moreover, the collection of umbilical cord blood poses no risk to the donor; there is no need for general anesthesia or blood replacement, and the procedure causes no discomfort. Whether cord blood lymphocytes are as likely to cause GVHD as lymphocytes from older individuals is unknown. Current clinical experience would suggest that the incidence may be low. Few of the patients transplanted with umbilical cord blood thus far have developed clinically significant GVHD, including recipients of HLA-disparate grafts. These results and associated laboratory findings pose intriguing possibilities for the future of umbilical cord blood stem cells in the setting of unrelated transplantation. With the marked incidence of grade 2-4 acute GVHD that is currently observed after unrelated bone marrow transplantation, a reduction in incidence or severity would be a major advancement in this field. In the setting of autologous trans-plantation, there are other intriguing possibilities; for example, cord blood may be an optimal source of pluripotential stem cells for gene therapy. The large-scale collection and storage of cord blood stem cells has become a reality. Pilot programs for the banking of unrelated umbilical cord blood have already begun in the United States and Europe. Not only is there the potential for reducing the time from search initiation to the time of donor stem cell acquisition but also there is the potential for reducing the risks associated with unrelated bone marrow transplantation. There is also the hope of remedying the shortage of donors from ethnic and racial backgrounds that are currently underrepresented in most unrelated donor programs. Even with the creation of such banks, it should not be forgotten that the collection of umbilical cord bloods should at least be considered when a child with leukemia, lymphoma, neuroblastoma, marrow failure syndrome, immunodeficiency state, or inborn error of metabolism has a mother who is pregnant. The clinical results to date in small recipients would suggest that it is at least as good as bone marrow; but additional patients and more time will be needed to finalize this conclusion.
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PMID:Allogeneic umbilical cord blood transplantation. 907 4

The aim of the present study was to assess the toxic potential of drugs of abuse and other neuropharmacological agents in the pathogenesis of AIDS dementia complex (ADC), the neurological complication of AIDS. Neuroblastoma and glioblastoma cell lines expressing the dopamine transporter, as well as primary macrophages exposed to human immunodeficiency virus-1 (HIV-1), were used to investigate the possibility of any synergistic effect between the mode of toxicity of such substances and virus exposure. The drugs of abuse used in our experiments were cocaine and morphine, which exert their action, among others, on the dopaminergic system. Effects were compared to treatment with dopamine itself and a typical dopaminergic drug used pharmaceutically, selegiline. In macrophage cultures, glutathione (GSH) was upregulated strongly after treatment with dopamine, morphine or selegiline, and this effect was enhanced when cells were pre-exposed to virus. This upregulation is discussed as a compensatory reaction to an oxidative signal. When hydrogen peroxide plus iron sulfate was used as a strong oxidant in macrophages, GSH concentrations decreased as a result of cell injury. Cell numbers remained constant in all treatment groups. In contrast, in both neuroblastoma and glioblastoma cell lines, the modulation of GSH concentrations by neurotropic substances was accompanied by significant cell loss, which was exacerbated by HIV-1 pretreatment. Selegiline did not change cell numbers when incubated alone. However, when incubated following treatment with HIV-1 cell death was highly significant. Ascorbic acid (AA), included as antioxidant, totally restored cell loss in cultures treated with dopamine. However, no effect was observed in combined treatment of AA and morphine or selegiline. The results demonstrate a synergistic role in cellular toxicity due to neurotropic substances and HIV-1, and suggest that neuropharmacological agents may contribute to the pathogenesis of ADC.
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PMID:Regulation of glutathione and cell toxicity following exposure to neurotropic substances and human immunodeficiency virus-1 in vitro. 937 55

Cervicothoracic lesions are not uncommon in children. All cervicothoracic lesions except superficial lesions extend from the neck to the thorax through the thoracic inlet. Evaluation of this area involves multiple imaging modalities: plain radiography, ultrasonography, nuclear medicine, computed tomography, and magnetic resonance (MR) imaging. However, MR imaging is the method of choice for assessing the full extents of cervicothoracic lesions and their relationships to neurovascular structures. Cervicothoracic lesions can be classified as congenital lesions, inflammatory lesions, benign tumors, malignant tumors, and traumatic lesions. Lymphangioma is the most common cervicothoracic mass in children; other congenital lesions include hemangioma, thymic cyst, and vascular anomalies. Inflammatory adenopathy reactive to tuberculosis, mononucleosis, tularemia, cat-scratch fever, infection with human immunodeficiency virus, or other upper respiratory tract infections can manifest as cervicothoracic lesions; tuberculous abscesses and abscesses of other origins can also be seen. Lipoma, lipoblastoma, aggressive fibromatosis, and nerve sheath tumors (either isolated lesions or those associated with neurofibromatosis) can also occur as cervicothoracic masses. Malignant cervicothoracic tumors include lymphoma, thyroid carcinoma, neuroblastoma, and chest wall tumors (rhabdomyosarcoma, Ewing sarcoma, and neuroectodermal tumor). Traumatic cervicothoracic lesions include pneumomediastinum of traumatic origin, traumatic pharyngeal pseudodiverticulum, esophageal foreign-body granuloma, and cervicothoracic hematoma.
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PMID:Cervicothoracic lesions in infants and children. 1033 90

A significant number of adult male patients with acquired immunodeficiency syndrome develop cerebral atrophy and progressive brain disorders such as dementia complex and neuropsychiatric problems. Upon entering the brain via activated macrophages or microglias, the human immunodeficiency type 1 virus (HIV-1) may produce cytotoxic factors such as HIV-1 envelope protein (gp120) and protease. Owing to significant proteolysis of nonviral proteins, the protease derived from HIV-1 may be detrimental to brain cells and neurons. Our results revealed that HIV-1 protease, at nanomolar concentrations, was as potent as gp120 in causing neurotoxicity in human neuroblastoma neurotypic SH-SY5Y cells. As shown by the Oncor ApopTag staining procedure, HIV-1 protease significantly increased the number of apoptotic cells over the serum-free controls. Moreover, HIV-1 protease-induced neurotoxicity was blocked by a selective protease inhibitor, kynostatin (KNI-272). Antioxidants such as 17beta-estradiol, melatonin, and S-nitrosoglutathione also prevented protease-induced neurotoxicity. These findings indicate that oxidative proteolysis may mediate HIV-1 protease-induced apoptosis and the degeneration of neurons and other brain cells. Centrally active protease inhibitors and antioxidants may play an important role in preventing cerebral atrophy and associated dementia complex caused by HIV-1.
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PMID:Kynostatin and 17beta-estradiol prevent the apoptotic death of human neuroblastoma cells exposed to HIV-1 protease. 1054 79

To infect target cells, the human immunodeficiency virus (HIV) type I (HIV-1) must engage not only the well-known CD4 molecule, but it also requires one of several recently described coreceptors. In particular, the CXCR4 (LESTR/fusin) receptor allows fusion and entry of T-tropic strains of HIV, whereas CCR5 is the major coreceptor used by primary HIV-1 strains that infect macrophages and CD4(+) T-helper cells (M-tropic viruses). In addition, the alpha chemokine SDF1alpha and the beta chemokines MIP1alpha, MIP1beta, and RANTES, natural ligands of CXCR4 and CCR5, respectively, are potent soluble inhibitors of HIV infection by blocking the binding between the viral envelope glycoprotein gp120 and the coreceptors. Approximately two-thirds of individuals with acquired immunodeficiency syndrome (AIDS) show neurologic complications, which are referred to a syndrome called AIDS dementia complex or HIV-1-associated cognitive/motor complex. The HIV-1 coat glycoprotein gp120 has been proposed as the major etiologic agent for neuronal damage, mediating both direct and indirect effects on the CNS. Furthermore, recent findings showing the presence of chemokine receptors on the surface of different cell types resident in the CNS raise the possibility that the association of gp120 with these receptors may contribute to the pathogenesis of neurological dysfunction. Here, we address the possible role of alpha and beta chemokines in inhibiting gp120-mediated neurotoxicity using the human neuroblastoma CHP100 cell line as an experimental model. We have previously shown that, in CHP100 cells, picomolar concentrations of gp120 produce a significant increase in cell death, which seems to proceed through a Ca(2+) - and NMDA receptor-dependent cascade. In this study, we gained insight into the mechanism(s) of neurotoxicity elicited by the viral glycoprotein. We found that CHP100 cells constitutively express both CXCR4 and CCR5 receptors and that stimulation with phorbol 12-myristate 13-acetate down-regulates their expression, thus preventing gp120-induced cell death. Furthermore, all the natural ligands of these receptors exerted protective effects against gp120-mediated neuronal damage, although with different efficiencies. These findings, together with our previous reports, suggest that the neuronal injury observed in HIV-1 infection could be due to direct (or indirect) interactions between the viral protein gp120 and chemokine and/or NMDA receptors.
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PMID:gp120 induces cell death in human neuroblastoma cells through the CXCR4 and CCR5 chemokine receptors. 1082 Jan 98

Inflammatory cytokines and human immunodeficiency virus type 1 (HIV-1) gp120 are considered to play an important role in the pathogenesis of HIV-1-associated CNS disorders. These substances are produced predominantly by HIV-1-infected or activated macrophages and microglia in the brain and induce neural cell death. Cepharanthine is a biscoclaurine alkaloid isolated from Stephania cepharantha Hayata and has been shown to have anti-inflammatory, anti-allergic, and immunomodulatory activities in vivo. We previously reported that this compound could inhibit tumor necrosis factor (TNF)-alpha- or phorbol 12-myristate 13-acetate-induced HIV-1 replication in latently infected U1 cells through the inhibition of nuclear factor-kappaB, a potent inducer of HIV-1 gene expression. In the present study, we demonstrated that cepharanthine suppresses the production of inflammatory cytokines and a chemokine, i.e. TNF-alpha, interleukin (IL)-1beta, IL-6, and IL-8, in human monocytic cell cultures, including primary monocyte/macrophage cultures. This effect of cepharanthine was concentration-dependent, and significant suppression was observed at 0.1 microg/mL. Furthermore, the compound also inhibited TNF-alpha- and gp120-induced death of differentiated human neuroblastoma cells at a concentration of 0.04 to 0.2 microg/mL. It penetrates the blood-brain barrier, and a medicine containing cepharanthine as a major component has been used in Japan for the treatment of patients with chronic inflammatory diseases. Thus, cepharanthine should be investigated further for its therapeutic and prophylactic potential in HIV-1-associated CNS disorders.
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PMID:Suppression of cytokine production and neural cell death by the anti-inflammatory alkaloid cepharanthine: a potential agent against HIV-1 encephalopathy. 1155 20

1. The role of the pro-inflammatory cytokine interleukin-1beta (IL-1beta) in the mechanism of cell death induced by the human immunodeficiency virus type 1 (HIV-1) recombinant coat glycoprotein, gp120 IIIB, has been studied in the human CHP100 neuroblastoma cell line maintained in culture. 2. Death of neuroblastoma cells typically elicited by 10 pM gp120 or by human recombinant IL-1beta (10 ng x ml(-1)) has been minimized by the antagonist of IL-1 receptor, i.e. IL-1ra (0.5 and 50 ng x ml(-1), respectively), an endogenous molecule that antagonizes most of the biological actions of IL-1beta, or by an antibody (5 and 50 ng x ml(-1)) which blocks the human IL-1 receptor type I (IL-1RI). 3. ELISA experiments have established that gp120 enhances immunoreactive IL-1beta levels in the culture medium and this is prevented by exposure to the IL-1 converting enzyme (ICE) inhibitor t-butoxycarbonyl-L-aspartic acid benzyl ester-chloromethylketone [Boc-Asp(OBzl)-CMK] used at a concentration (2.5 microM) which significantly (P<0.001) reduces cell death. 4. Death of CHP100 cells induced by gp120 is also prevented by acetyl-Tyr-Val-Ala-Asp-chloromethylketone (Ac-YVAD-CMK; 10-100 microM), a second inhibitor of ICE, supporting the concept that the viral protein stimulates the conversion of the 31 kDa pro-IL-1beta in to the 17 kDa mature cytokine which is then secreted to cause death. 5. In conclusion, our present data demonstrate that gp120 stimulates the secretion of IL-1beta which then triggers CHP100 neuroblastoma cell death via stimulation of IL-1 receptor type I.
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PMID:HIV-1 coat protein gp120 stimulates interleukin-1beta secretion from human neuroblastoma cells: evidence for a role in the mechanism of cell death. 1170 56


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