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1.
Euroasian J Hepatogastroenterol ; 14(1): 81-85, 2024.
Article in English | MEDLINE | ID: mdl-39022205

ABSTRACT

Background: Surgery remains the mainstay in treating intussusception in developing nations. A correspondingly high bowel resection rate exists despite a shift to nonoperative reduction in high-income countries. We aimed to study the clinical profile of the patients with intussusception presenting to our hospital and to assess the clinical and radiological predictors of success or failure of nonoperative management of intussusception. Materials and methods: This prospective study was conducted in the Department of Pediatric Surgery over a period of 3 years and included a total of 118 patients who presenting to our emergency division with features suggestive of intussusception and were managed accordingly either with hydrostatic reduction or by surgical intervention. Results: We observed that the majority of the patients were males (65.5%). The mean age was 13.54 months. Intermittent pain was the most common symptom. Both pain and vomiting did not affect the outcome. Lab parameters like raised total leukocyte counts (TLC), C-reactive protein (CRP) and lactate levels were significantly associated with failure of hydrostatic reduction. Patients with air fluid levels on X-ray were more likely to end up in surgery. Ultrasound findings of bowel wall edema, aperistaltic gut loops and a pathological lead point was associated with failure of hydrostatic reduction as well. The overall success rate of hydrostatic reduction was 85.5%. Conclusion: Hydrostatic reduction of intussusception is a safe and effective method of management of intussusception whenever indicated. Factors that might reduce the chance of its success include continuous pain, irritability, tenderness, deranged lab parameters like TLC, CRP and lactate levels, air fluid levels on X-ray, bowel wall edema, aperistalsis and the presence of a lead point. How to cite this article: Shah JY, Banday I, Hamdani HZ, et al. A Study of Predictors of Failure of Nonoperative Management of Ileocolic Intussusception in Children. Euroasian J Hepato-Gastroenterol 2024;14(1):81-85.

2.
Dalton Trans ; 49(35): 12418-12431, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32852029

ABSTRACT

Catalysis using earth abundant metals is an important goal due to the relative scarcity and expense of precious metal catalysts. It would be even more beneficial to use earth abundant catalysts for the synthesis of common pharmaceutical structural motifs such as pyrrolidine and pyridine. Thus, developing titanium catalysts for asymmetric ring closing hydroamination is a valuable goal. In this work, four sterically encumbered chiral sulfonamides derived from naturally occurring amino acids were prepared. These compounds undergo protonolysis reactions with Ti(NMe2)4 or Ta(NMe2)5 to give monomeric complexes as determined by both DOSY NMR and X-ray crystallography. The resulting complexes are active for the ring closing hydroamination hepta-4,5-dienylamine to give a mixture of tetrahydropyridine and pyrrolidine products. However, the titanium complexes convert 6-methylhepta-4,5-dienylamine exclusively to 2-(2-methylpropenyl)pyrrolidine in higher enantioselectivity than those previously reported, with enantiomeric excesses ranging from 18-24%. The corresponding tantalum complexes were more selective with enantiomeric excesses ranging from 33-39%.

4.
Anat Cell Biol ; 46(2): 122-30, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23869259

ABSTRACT

The present study examined the efficacy of Ocimum basilicum (basil) extract, a natural herb, with antioxidant properties, against testicular toxicity induced by cadmium (Cd), which is one of the most important toxic heavy metals. The intoxicated rats showed significant alterations in the testicular tissue including decreased seminiferous epithelium height and changes in the arrangement of spermatogenic layers. Hypospermatogensis with cytoplasmic vacuolization and pyknotic nuclei were observed. Intertubular hemorrahage and absence of spermatozoa were noted. Decreased cell proliferation was reflected by a decrease in Ki-67 expression, whereas the increase in apoptotic rate was associated with a decrease in the Bcl/Bax ratio. Concomitant treatment with aqueous basil extract led to an improvement in histological, morphometrical and immunohistochemical changes induced by Cd. The beneficial effects of basil extract could be attributed to its antioxidant properties.

5.
Anatomy & Cell Biology ; : 122-130, 2013.
Article in English | WPRIM (Western Pacific) | ID: wpr-188659

ABSTRACT

The present study examined the efficacy of Ocimum basilicum (basil) extract, a natural herb, with antioxidant properties, against testicular toxicity induced by cadmium (Cd), which is one of the most important toxic heavy metals. The intoxicated rats showed significant alterations in the testicular tissue including decreased seminiferous epithelium height and changes in the arrangement of spermatogenic layers. Hypospermatogensis with cytoplasmic vacuolization and pyknotic nuclei were observed. Intertubular hemorrahage and absence of spermatozoa were noted. Decreased cell proliferation was reflected by a decrease in Ki-67 expression, whereas the increase in apoptotic rate was associated with a decrease in the Bcl/Bax ratio. Concomitant treatment with aqueous basil extract led to an improvement in histological, morphometrical and immunohistochemical changes induced by Cd. The beneficial effects of basil extract could be attributed to its antioxidant properties.


Subject(s)
Animals , Rats , Apoptosis , Cadmium , Cell Proliferation , Cytoplasm , Metals, Heavy , Ocimum , Ocimum basilicum , Seminiferous Epithelium , Spermatozoa , Testis
6.
Thromb Res ; 129(6): 760-4, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22225857

ABSTRACT

BACKGROUND: Thiazolidinediones (TZDs) are agonists of PPARγ and exert beneficial metabolic effects in patients with diabetes. They may also affect platelet function. OBJECTIVES: To characterize potential platelet inhibitory effect of pioglitazone alone and in the presence of aspirin. METHODS: 20 normal and 20 diabetic subjects were enrolled in a prospective study. On day 1, a blood sample was obtained at baseline and a second one after ingestion of 30mg of pioglitazone. PRP was prepared and platelet aggregation and release were evaluated using ADP, collagen and arachidonic acid as agonists. Subjects returned at 6-9days later after ingesting a single 81mg dose of aspirin and a third blood sample was obtained. The subjects then again ingested 30mg of pioglitazone and a fourth and final blood sample was obtained. Platelet aggregation and release were measured. PRP was incubated with thrombin to activate platelets, and the serum was separated and assayed for thromboxane B2, TGFß and CD40L RESULTS: Pioglitazone alone did not affect aggregation with arachidonic acid. However, following ingestion of both aspirin and pioglitazone aggregation was significantly decreased compared to aspirin alone (P<0.0001). Pioglitazone also potentiated aspirin-induced inhibition of ATP release using either arachidonic acid or collagen. Following pioglitazone alone, TXB(2) release was 32,719±3,585pg/ml which was significantly reduced compared to baseline (42,075±4,479, P=0.0004). Pioglitazone also potentiated the inhibition of TXB(2) release by aspirin. CONCLUSION: Pioglitazone inhibits platelet function and potentiates the inhibitory effects of aspirin.


Subject(s)
Aspirin/pharmacology , Blood Platelets/drug effects , Diabetes Mellitus/blood , Diabetes Mellitus/drug therapy , Hypoglycemic Agents/pharmacology , Thiazolidinediones/pharmacology , Aspirin/administration & dosage , Blood Platelets/physiology , Case-Control Studies , Drug Synergism , Female , Humans , Hypoglycemic Agents/administration & dosage , Male , Middle Aged , Pioglitazone , Platelet Aggregation/drug effects , Platelet Function Tests , Prospective Studies , Thiazolidinediones/administration & dosage
7.
Wiad Lek ; 56(7-8): 375-7, 2003.
Article in Polish | MEDLINE | ID: mdl-14969168

ABSTRACT

In this work we present a patient, aged 40 with Ramsay Hunt syndrome, who was treated at the Department of Infectious Disease, Medical Academy in Lublin (Poland). The diagnosis of the disease was based on the anamnesis concerning epidemiology of the disease, the course and three major symptoms: facial paralysis, neuralgia, herpetic eruption in the mouth and on the ear. The combined treatment with antiviral drugs and corticosteroids was partially successful and did not resolve the seventh nerve palsy.


Subject(s)
Facial Nerve/physiopathology , Herpes Zoster Oticus , Adrenal Cortex Hormones/administration & dosage , Adult , Antiviral Agents/administration & dosage , Cranial Nerve Diseases/virology , Facial Paralysis/virology , Herpes Zoster Oticus/complications , Herpes Zoster Oticus/diagnosis , Herpes Zoster Oticus/drug therapy , Herpes Zoster Oticus/physiopathology , Humans , Male , Neuralgia/virology , Time Factors , Treatment Outcome
8.
Blood ; 98(7): 2275-8, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11568018

ABSTRACT

To identify the regulatory elements controlling expression of the human CD4 (hCD4) gene in different cell types of the immune system, deletion and chimeric (human/murine) reporter genes were constructed and tested in transgenic (Tg) mice. Regulatory elements required for the proper hCD4 expression in the immature double-positive thymic T cells were identified in the enhancer and in the 3' end of intron 1. Expression of hCD4 in macrophages is controlled by at least 2 sets of regulatory elements: one present in front of exon 1 and the second at the 5' end of intron 1. The hCD4 elements required for expression on both myeloid and lymphoid CD8alpha(+) dendritic cells (DCs) from lymph node and thymus were found to be different from those required for macrophage expression. The results indicate that expression of hCD4 in T cells, macrophages, and DCs is controlled by distinct regulatory elements.


Subject(s)
CD4 Antigens/genetics , Dendritic Cells/metabolism , Genes, Regulator/genetics , Macrophages/metabolism , T-Lymphocytes/metabolism , Animals , Blotting, Northern , CD4 Antigens/metabolism , DNA/metabolism , Flow Cytometry , Gene Expression Regulation/genetics , Humans , Mice , Mice, Transgenic , Tissue Distribution
9.
J Virol ; 75(19): 9378-92, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11533201

ABSTRACT

The human immunodeficiency virus type 1 (HIV-1) Nef protein is an important determinant of AIDS pathogenesis. We have previously reported that HIV-1 Nef is responsible for the induction of a severe AIDS-like disease in CD4C/HIV transgenic (Tg) mice. To understand the molecular mechanisms of this Nef-induced disease, we generated Tg mice expressing a mutated Nef protein in which the SH3 ligand-binding domain (P(72)XXP(75)XXP(78)) was mutated to A(72)XXA(75)XXQ(78). This mutation completely abolished the pathogenic potential of Nef, although a partial downregulation of the CD4 cell surface expression was still observed in these Tg mice. We also studied whether Hck, one of the effectors previously found to bind to this PXXP motif of Nef, was involved in disease development. Breeding of Tg mice expressing wild-type Nef on an hck(-/-) (knockout) background did not abolish any of the pathological phenotypes. However, the latency of disease development was prolonged. These data indicate that an intact PXXP domain is essential for inducing an AIDS-like disease in CD4C/HIV Tg mice and suggest that interaction of a cellular effector(s) with this domain is required for the induction of this multiorgan disease. Our findings indicate that Hck is an important, but not an essential, effector of Nef and suggest that another factor(s), yet to be identified, may be more critical for disease development.


Subject(s)
Genes, nef , HIV Infections/virology , HIV-1/genetics , Protein-Tyrosine Kinases/genetics , Proto-Oncogene Proteins/genetics , Animals , CD4 Antigens/genetics , HIV Infections/genetics , HIV-1/pathogenicity , Humans , Mice , Mice, Transgenic , Mutation , Proto-Oncogene Proteins c-hck , Virulence/genetics , Virus Replication/genetics , src Homology Domains
10.
Immunity ; 15(2): 173-85, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11520454

ABSTRACT

The mechanisms responsible for degeneration of germinal centers (GC) and follicular dendritic cell (FDC) networks during progression to AIDS remain elusive. Here, we show that CD4(+) T cells from CD4C/HIV-1 Tg mice, which develop a severe AIDS-like disease, express low levels of CD40 ligand. Accordingly, GC formation, FDC networks, and immunoglobulin isotype switching are impaired in these animals. However, Tg B cells respond to in vitro CD40 stimulation. Total serum IgG levels are reduced in Tg mice, whereas total IgM levels are increased with a significant amount showing DNA specificity. IFN-gamma- and IL-6-deficient CD4C/HIV Tg mice also develop the AIDS-like disease and produce auto-Ab. Thus, CD4C/HIV Tg mice have immune dysfunction accompanied by autoimmune responses.


Subject(s)
Acquired Immunodeficiency Syndrome/immunology , Autoantibodies/blood , CD4 Antigens/immunology , Germinal Center/immunology , HIV-1/immunology , Acquired Immunodeficiency Syndrome/etiology , Animals , B-Lymphocytes , CD4 Antigens/genetics , Gene Products, nef/immunology , Genes, nef , HIV-1/genetics , Hematopoietic Stem Cells , Immunoglobulin Class Switching , Immunoglobulin M/blood , Interferon-gamma/metabolism , Interleukin-6/metabolism , Lymphocyte Activation , Mice , Mice, Transgenic , Mutation , nef Gene Products, Human Immunodeficiency Virus
12.
Cell ; 95(2): 163-75, 1998 Oct 16.
Article in English | MEDLINE | ID: mdl-9790524

ABSTRACT

Transgenic (Tg) mice expressing the complete coding sequences of HIV-1 in CD4+ T cells and in cells of the macrophage/dendritic lineages develop severe AIDS-like pathologies: failure to thrive/weight loss, diarrhea, wasting, premature death, thymus atrophy, loss of CD4+ T cells, interstitial pneumonitis, and tubulo-interstitial nephritis. The generation of Tg mice expressing selected HIV-1 gene(s) revealed that nef harbors a major disease determinant. The latency and progression (fast/slow) of the disease were strongly correlated with the levels of Tg expression. Nef-expressing Tg thymocytes were activated and alpha-CD3 hyperresponsive with respect to tyrosine phosphorylation of several substrates, including LAT and MAPK. The similarity of this mouse model to human AIDS, particularly pediatric AIDS, suggests that Nef may play a critical role in human AIDS, independently of its role in virus replication.


Subject(s)
Acquired Immunodeficiency Syndrome/virology , F-Box Proteins , Gene Products, nef/genetics , HIV-1/pathogenicity , Ubiquitin-Protein Ligases , Acquired Immunodeficiency Syndrome/mortality , Animals , CD3 Complex/analysis , Cell Cycle Proteins/genetics , DNA, Viral/analysis , Erythrocyte Count , F-Box-WD Repeat-Containing Protein 7 , Flow Cytometry , Gene Expression Regulation, Viral , Genes, Viral , HIV-1/genetics , In Situ Hybridization , Leukocyte Count , Lymphoid Tissue/virology , Mice , Mice, Transgenic , Mutagenesis/physiology , Phenotype , Phosphorylation , RNA, Viral/analysis , Survival Analysis , Thymus Gland/chemistry , Thymus Gland/cytology , Thymus Gland/virology , Tyrosine/metabolism , Virulence , Virus Replication , nef Gene Products, Human Immunodeficiency Virus
13.
Biochem Soc Symp ; 63: 159-65, 1998.
Article in English | MEDLINE | ID: mdl-9513720

ABSTRACT

Mouse mammary tumour virus (MMTV)/neu transgenic mice develop clonal or oligoclonal mammary tumours stochastically. The pathology of these tumours is very similar to that of human breast tumours. Moreover, these mouse tumours metastasize in the lungs. We present evidence that this mouse model of human breast tumours can be instrumental in identifying novel genes of two distinct classes (activated oncogenes or tumour suppressor genes) which may collaborate with the c-erbB-2/neu transgenic oncogene.


Subject(s)
Mammary Neoplasms, Experimental/genetics , Mammary Tumor Virus, Mouse/genetics , Receptor, ErbB-2/genetics , Animals , Breast Neoplasms/genetics , Female , Genes, Tumor Suppressor , Humans , Mammary Neoplasms, Experimental/pathology , Mammary Neoplasms, Experimental/virology , Mice , Mice, Transgenic
14.
J Virol ; 72(1): 121-32, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9420207

ABSTRACT

We have constructed transgenic (Tg) mice expressing the entire human immunodeficiency virus type 1 (HIV-1) coding sequences in cells targeted by HIV-1 infection in humans. These Tg mice developed a severe AIDS-like disease leading to early death (< 1 month). They developed muscle wasting, severe atrophy and fibrosis of lymphoid organs, tubulointerstitial nephritis, and lymphoid interstitial pneumonitis. In addition the expression of RANTES was increased in various tissues of these Tg mice relative to that in the normal controls. Disease appearance was correlated with the levels of transgene expression. The numerous pathologies observed in these mice are remarkably similar to those observed in human AIDS and, more specifically, in pediatric AIDS.


Subject(s)
Acquired Immunodeficiency Syndrome/etiology , HIV-1/pathogenicity , Acquired Immunodeficiency Syndrome/immunology , Acquired Immunodeficiency Syndrome/pathology , Animals , Base Sequence , CD4 Antigens/genetics , Chemokine CCL5/genetics , DNA Primers/genetics , Disease Models, Animal , Female , Gene Expression , Genome, Viral , HIV-1/genetics , HIV-1/immunology , Humans , Immune System/virology , Male , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Transgenic , Mosaicism , Phenotype
15.
Genes Dev ; 10(15): 1930-44, 1996 Aug 01.
Article in English | MEDLINE | ID: mdl-8756350

ABSTRACT

The MMTVD/myc transgenic mice spontaneously develop oligoclonal CD4+CD8+ T-cell tumors. We used provirus insertional mutagenesis in these mice to identify putative collaborators of c-myc. We found that Notch1 was mutated in a high proportion (52%) of these tumors. Proviruses were inserted upstream of the exon coding for the transmembrane domain and in both transcriptional orientations. These mutations led to high expression of truncated Notch1 RNAs and proteins (86-110 kD). In addition, many Notch1-rearranged tumors showed elevated levels of full-length Notch1 transcripts, whereas nearly all showed increased levels of full-length (330-kD) or close to full-length (280-kD) Notch1 proteins. The 5' end of the truncated RNAs were determined for some tumors by use of RT-PCR and 5' RACE techniques. Depending on the orientation of the proviruses, viral LTR or cryptic promoters appeared to be utilized, and coding potential began in most cases in the transmembrane domain. Pulse-chase experiments revealed that the 330-kD Notch1 proteins were processed into 110- and 280-kD cleavage products. These results suggest that Notch1 can be a frequent collaborator of c-myc for oncogenesis. Furthermore, our data indicate that Notch1 alleles mutated by provirus insertion can lead to increased expression of truncated and full-length (330/280-kD) Notch1 proteins, both being produced in a cleaved and uncleaved form.


Subject(s)
Genes, myc , Mammary Tumor Virus, Mouse/genetics , Membrane Proteins/genetics , Moloney murine leukemia virus/genetics , Receptors, Cell Surface , Thymoma/genetics , Transcription Factors , Animals , Base Sequence , Blotting, Northern , DNA Transposable Elements , Gene Expression Regulation, Neoplastic , Membrane Proteins/biosynthesis , Membrane Proteins/metabolism , Mice , Mice, Transgenic , Molecular Sequence Data , Mutagenesis, Insertional , RNA/chemistry , Receptor, Notch1 , Repetitive Sequences, Nucleic Acid , T-Lymphocytes/pathology , Thymoma/pathology , Thymoma/virology , Transcription, Genetic , Tumor Cells, Cultured
16.
J Virol ; 69(1): 60-8, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7983763

ABSTRACT

Pr60gag appears to be the only protein encoded by the murine AIDS (MAIDS)-defective virus. To study the role of Pr60gag or some other sequences of the viral genome in the pathogenicity of the virus, we have generated mutants of the defective viral genome. These mutant defective viruses, prepared as helper-free stocks, were inoculated into susceptible C57BL/6 mice. Mutant Du5H-A virus, which had a stop codon within gag MA(p15), did not induce target cell proliferation or MAIDS. Mutants Du5H-B and -C encoded truncated Pr60gag proteins containing, respectively, MA(p15)-p12 or MA(p15)-p12 and part of CA(p30). These mutants showed a very limited capacity to induce early cell expansion and were poorly pathogenic. Only recombinant (revertant) viruses were recovered from organs of diseased mice inoculated with these two mutants. Mutant Du5H-D was generated by deleting 1.4 kbp of the 3'-end sequences, outside the gag coding region. The levels of RNA and proteins made by this mutant were low. This mutant also reverting frequently but was nevertheless able to induce MAIDS at a low efficiency without reverting. Our results indicate that the Pr60gag protein is necessary and sufficient to induce MAIDS. These data also suggest that the Pr60gag protein needs to be relatively intact to be fully pathogenic. In addition, our study shows a very high reversion rate of some mutants and emphasizes the need to check for the presence of revertant (recombinant) viruses in diseased organs when working with mutants of the MAIDS-defective virus.


Subject(s)
Gene Products, gag/genetics , Genome, Viral , Leukemia Virus, Murine/genetics , Murine Acquired Immunodeficiency Syndrome/virology , Animals , Base Sequence , Cells, Cultured , DNA Primers , Fibroblasts/virology , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Murine Acquired Immunodeficiency Syndrome/metabolism , Mutation , RNA, Viral , Recombination, Genetic
17.
Mol Cell Biol ; 14(2): 1084-94, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8289789

ABSTRACT

The CD4 protein plays a critical role in the development and function of the immune system. To gain more insight into the mechanism of expression of the human CD4 gene, we cloned 42.2 kbp of genomic sequences comprising the CD4 gene and its surrounding sequences. Studies with transgenic mice revealed that a 12.6-kbp fragment of the human CD4 gene (comprising 2.6 kbp of 5' sequences upstream of the transcription initiation site, the first two exons and introns, and part of exon 3) contains the sequences required to support the appropriate expression in murine mature CD4+ CD8- T cells and macrophages but not in immature double-positive CD4+ CD8+ T cells. Expression in CD4+ CD8+ T cells was found to require additional regulatory elements present in a T-cell enhancer fragment recently identified for the murine CD4 gene (S. Sawada and D. R. Littman, Mol. Cell. Biol. 11:5506-5515, 1991). These results suggest that expression of CD4 in mature and immature T-cell subsets may be controlled by distinct and independent regulatory elements. Alternatively, specific regulatory elements may control the expression of CD4 at different levels in mature and immature T-cell subsets. Our data also indicate that mouse macrophages contain the regulatory factors necessary to transcribe the human CD4 gene.


Subject(s)
CD4 Antigens/biosynthesis , Gene Expression , Macrophages/metabolism , Promoter Regions, Genetic , T-Lymphocyte Subsets/metabolism , T-Lymphocytes/metabolism , Animals , Base Sequence , Blotting, Northern , Blotting, Southern , CD4 Antigens/analysis , CD4 Antigens/genetics , CD8 Antigens/analysis , Cloning, Molecular , DNA/analysis , Enhancer Elements, Genetic , Exons , Flow Cytometry , Genomic Library , Humans , Introns , Macrophages/immunology , Mice , Mice, Transgenic , Molecular Sequence Data , Organ Specificity , Regulatory Sequences, Nucleic Acid , Restriction Mapping , Sequence Homology, Nucleic Acid , Spleen/immunology , Spleen/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocytes/immunology , Thymus Gland/immunology , Thymus Gland/metabolism
18.
Res Immunol ; 145(1): 5-16, 1994 Jan.
Article in English | MEDLINE | ID: mdl-7912001

ABSTRACT

CD4 is a cell surface molecule expressed mostly on cells of the T-cell lineage. Studies have shown that this molecule plays an important role in positive and negative selection of T cells in the thymus. It is not surprising therefore, that in T-cell ontogeny, CD4 starts to be expressed on thymocyte subpopulations about to undergo these selection processes. The human CD4 molecule was expressed in mouse thymus ontogeny using a promoter, MMTVD, which targets expression as early as day 14 of ontogeny, prior to expression of endogenous TCR, CD4 and CD8. Thymic ontogeny is delayed in foetal MMTVD-CD4 mice. Human CD4-expressing thymuses show a twofold reduction in cellularity at days 17 and 18 of ontogeny compared with non-transgenic control littermate thymuses, and paradoxically, MMTVD-CD4 thymuses contain more cells in the S and G2/M stages of the cell cycle than control thymuses do. At the cell surface marker level, MMTVD-CD4 thymocytes show a delay in surface expression of CD3, murine CD4 and murine CD8, along with persistent expression of IL2R alpha compared with foetal non-transgenic littermates. Biochemical studies show that, although MMTVD-CD4 thymocytes do not express surface CD3, cytoplasmic CD3 epsilon proteins as well as TCR beta incomplete and complete transcripts are present in foetal day-17 thymocytes. Low levels of surface CD3/TCR expression, however, could partly be due to the low levels of zeta mRNA and proteins detected in these cells. These results suggest that CD4 is not expressed until a certain stage of differentiation not only because it is not yet required for selection processes, but because it can lead to a reversible deregulation of thymocyte development.


Subject(s)
CD4 Antigens/immunology , CD4-Positive T-Lymphocytes/immunology , T-Lymphocytes, Regulatory/immunology , Thymus Gland/immunology , Animals , Antibodies, Monoclonal , CD3 Complex/genetics , CD3 Complex/immunology , Cell Cycle , Cell Differentiation , Flow Cytometry , Gene Expression , Immunoblotting , Mice , Mice, Transgenic , RNA, Messenger/metabolism , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/immunology , Thymus Gland/cytology
19.
Oncogene ; 8(6): 1661-6, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8502486

ABSTRACT

The Vin-1 gene was initially identified as a gene whose expression is altered by the integration of proviruses in the Vin-1 common site of integration in retrovirus-induced rodent T-cell leukemias. We have now isolated the Vin-1 cDNA. Sequencing of the Vin-1 cDNA and Vin-1 exons revealed that the proviruses are integrated at the 5' end of the Vin-1 gene in an inverse transcriptional orientation. The sequence of the Vin-1 gene is identical to that of the recently identified G1-phase cyclin D2 gene. The human homolog of the Vin-1/cyclin D2 gene (CCND2) was mapped to chromosome 12, band p13.3, by in situ hybridization, confirming previous mapping data. Our results strongly support a role of the cyclin D2 gene in oncogenesis and thereby implicate altered cell cycle regulation in transformation.


Subject(s)
Chromosomes, Human, Pair 12 , Cyclins/genetics , Leukemia, T-Cell/genetics , Oncogenes , Proviruses/genetics , Amino Acid Sequence , Animals , Base Sequence , Brain/metabolism , Cell Transformation, Neoplastic , Chromosome Banding , Chromosome Mapping , Cloning, Molecular , Cyclin D2 , DNA, Neoplasm/genetics , DNA, Neoplasm/isolation & purification , Exons , Gene Library , Humans , Mice , Molecular Sequence Data , Multigene Family , Mutagenesis, Insertional , Rats , Restriction Mapping , Sequence Homology, Amino Acid , Spleen/metabolism , Transcription, Genetic , Virus Integration
20.
Mol Cell Biol ; 12(8): 3522-30, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1321339

ABSTRACT

The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to be derived from the progenitor double-positive T cells. These results suggest the existence of similar and common factors in CD4+ CD8- and CD4- CD8+ T cells and support a model of differentiation of CD4+ CD8+ T cells through common signal(s) involved in turning off the expression of the CD4 or CD8 gene.


Subject(s)
CD4 Antigens/genetics , CD4 Antigens/immunology , CD8 Antigens/immunology , Genes, myc , Mammary Tumor Virus, Mouse/genetics , Repetitive Sequences, Nucleic Acid , T-Lymphocytes/immunology , Animals , Antibodies, Monoclonal , Antisense Elements (Genetics) , Flow Cytometry , Humans , Mice , Mice, Nude , Mice, Transgenic , Phenotype , RNA Probes , Restriction Mapping , T-Lymphocyte Subsets/immunology , Thymoma/genetics , Thymoma/immunology , Thymus Gland/immunology , Thymus Neoplasms/genetics , Thymus Neoplasms/immunology , Transcription, Genetic
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