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J Lacoste

Publications and source records attributed to J Lacoste.

At least 19 recordsLinked to original sources
PubMed1991

NF-kappa B activity in T cells stably expressing the Tax protein of human T cell lymphotropic virus type I.

The effect of constitutive Tax expression on the interaction of NF-kappa B with its recognition sequence and on NF-kappa B-dependent gene expression was examined in T lymphoid Jurkat cell lines (19D and 9J) stably transformed with a Tax expression vector. Tax expressing T cell lines contained a constitutive level of NF-kappa B binding activity, detectable by mobility shift assay and uv cross-linking using a palindromic NF-kappa B probe homologous to the interferon beta PRDII site. In Jurkat and NC2.10 induction with phorbol esters resulted in the appearance of new DNA binding proteins of 85, 75, and 54 kDa, whereas in Tax expressing cells the 85-kDa protein and a 92-kDa DNA binding protein were constitutively induced. Expression of Tax protein in 19D and 9J resulted in transcription of the endogenous NF-kappa B-dependent granulocyte-macrophage colony stimulating factor gene and increased basal level expression of transfected NF-kappa B-regulated promoters. Nonetheless transcription of both the endogenous and the transfected gene was inducible by PMA treatment. Tax expression in Jurkat T cells may alter the stoichiometry of NF-kappa B DNA binding proteins and thus change the expression of NF-kappa B-regulated promoters.

Cell Line↗
PubMed1991

Stimulation of interferon beta gene transcription in vitro by purified NF-kappa B and a novel TH protein.

The human interferon beta (IFN-beta) regulatory element consists of multiple enhanson domains which are targets for transcription factors involved in inducible expression of the promoter. To further characterize the protein-DNA interactions mediating IFN-beta induction, positive regulatory domain (PRD) II binding proteins were purified from phorbol ester induced Jurkat T-cells and from IFN primed, cycloheximide/polyinosinic-polycytidylic acid treated HeLa S3 cells. From HeLa cells, two major proteins of 52 and 45 kilodaltons (kD) copurified with DNA binding activity, whereas from T-cells, four proteins--a major protein of 52 kD and three minor proteins of 82, 67, and 43-47 kD--were purified. Also, an induction specific DNA binding protein was purified from HeLa cells that interacted with the (AAGTGA)4 tetrahexamer sequence and the PRDI domain. This protein is immunologically distinct from IRF-1/ISGF2. Uninduced or Sendai virus induced HeLa extracts were used to examine transcription in vitro using a series of IFN beta promoter deletions. Deletions upstream of the PRDII element increased transcription in the uninduced extract, indicating predominantly negative regulation of the promoter. A 2-4-fold increase in IFN-beta promoter transcription was observed in Sendai virus induced extracts, and deletion of PRDI and PRDII elements decreased this induced level of transcription. When purified PRDII and tetrahexamer binding proteins were added to the induced extract, a 4-fold increase in transcription was observed. These experiments demonstrate that it is possible to modulate IFN-beta transcription in vitro but indicate that additional proteins may be required to fully activate IFN-beta transcription.

Amino Acid Sequence↗
PubMed1990

Inhibition of HIV-1 transmission by interferon and 3'-azido-3'-deoxythymidine during de novo infection of promonocytic cells.

HIV-1 infection of promonocytic U937 cells was used to examined induction of IFN-alpha/beta gene expression and to determine the inhibitory effects of IFN-alpha 2 and/or AZT on de novo HIV-1 infection, initiated either by coculture of virus-shedding U9-IIIB cells with uninfected cells or by incubation of U937 cells with virus-containing supernatants. Usually 21-28 days were required to transmit virus to greater than 90% of the cell culture. HIV-1 infection did not stimulate constitutive production of endogenous IFN-alpha 1/alpha 2 or IFN-beta genes, although induction of IFN RNA was observed following coinfection with the paramyxovirus Sendai. Exogenous rIFN-alpha 2 treatment decreased the intracellular accumulation of viral RNA 5- to 20-fold as determined by Northern blot analysis and the extracellular levels of HIV-1 as measured by p24 ELISA antigen capture. The effect was most dramatic at a time coincident with the rapid increase in virus spread through the cell culture (Days 10-18). During the fourth week of infection, HIV-1 multiplication was able to overcome the IFN-induced block in virus spread. AZT was not effective in limiting virus spread in the cocultivation experiments. When U937 cells were infected with virus-containing supernatants from U9-IIIB cells, IFN and AZT acted in combination to limit the number of infected cells and to inhibit intracellular accumulation of viral RNA. These experiments suggest that subtle differences in the mode of virus transmission in monocytic cells may alter the efficacy of combination antiretroviral therapy.

Blotting, Northern↗
PubMed1990

Cell-specific differences in activation of NF-kappa B regulatory elements of human immunodeficiency virus and beta interferon promoters by tumor necrosis factor.

Three aspects of the involvement of tumor necrosis factor in human immunodeficiency virus (HIV) pathogenesis were examined. Tumor necrosis factor alpha (TNF-alpha) mRNA production was analyzed by polymerase chain reaction amplification in monocytic U937 cells and in a chronically HIV infected U937 cell line (U9-IIIB). TNF-alpha RNA was undetectable in U937 cells, whereas a low constitutive level was detected in U9-IIIB cells. Paramyxovirus infection induced a 5- to 10-fold increase in the steady-state level of TNF-alpha RNA in U9-IIIB cells compared with U937 cells, suggesting that HIV-infected monocytic cells produced higher levels of TNF-alpha than did normal cells after a secondary virus infection. The effects of TNF-alpha on gene expression were examined by transient expression assays using reporter chloramphenicol acetyltransferase plasmids linked to regulatory elements from the HIV long terminal repeat (LTR) and the beta interferon promoter. In U937 and Jurkat T lymphoid cells, the inducibility of the different hybrid promoters by TNF-alpha or phorbol ester varied in a cell type- and promoter context-specific manner; the levels of gene activity of NF-kappa B-containing plasmids correlated directly with induction of NF-kappa B DNA-binding activity. Although the intact beta interferon promoter was only weakly stimulated by phorbol ester or TNF-alpha, multimers of the PRDII NF-kappa B-binding domain were inducible by both agents. TNF-alpha was able to increase expression of the HIV LTR in T cells, but in monocytic cells, TNF-alpha did not induce the HIV LTR above a constitutive level of activity. This level of NF-kappa B-independent activity appears to be sufficient for virus multiplication, since TNF-alpha treatment had no effect on the kinetics of de novo HIV type 1 (HIV-1) infection and viral RNA production in U937 cells. However, in Jurkat cells, TNF-alpha dramatically enhanced the spread of HIV-1 through the cell population and increased viral RNA synthesis, indicating that in T cells HIV-1 multiplication was stimulated by TNF-alpha treatment.

Base Sequence↗
PubMed1990

Clinical experience with leuprorelin acetate before radiotherapy for prostatic cancer.

A total of 40 patients with stages A2 to C prostatic cancer were treated with leuprorelin acetate depot once a month for 2 months before being treated by pelvic irradiation or radical prostatectomy. In the 32 patients who were evaluable, seven (22%) were classified as minor responders after leuprorelin treatment and 23 (72%) as major responders when assessed by rectal examination. Prostate-specific antigens also returned to normal concentrations (5 ng/ml) in 26/31 (84%) patients. Leuprorelin acetate depot suppressed plasma testosterone concentrations to castration values during treatment, but concentrations returned to normal 2 months after completion of treatment. Following radical treatment, there were three deaths--one postoperative and two due to recurrent disease--but there was no isolated local relapse. It is concluded that the protocol was locally well tolerated and was effective in the treatment of stages B2 and C prostatic cancer patients.

Aged↗
PubMed1988

[Dysuria in women and bladder hypocontractibility].

Urodynamic tests used to analyze 120 cases of non-neurogenic and non-iatrogenic dysuria in women provided data to which the following criteria were applied: maximum output less than 15 ml/s and/or residue greater than 100 ml. Clinical examination, including endoscopy, established a possible obstructive cause in 60 cases (36 patients with prolapse, 12 with urethral stenosis and 12 with cervical disease) the 60 other cases remaining unexplained. The frequency of reduced or absent contractility, 68% in the total population, is still 58% when a cervico-urethral obstruction exists.

Adolescent↗
PubMed1987

[Primary megabladder in adults. Comments apropos of 21 cases].

Based on a review of 21 cases, clinical, urodynamic and therapeutic a of primary megalocystis in adults are discussed. This rare entity is defined as an abnormally large bladder capacity in the absence of any obstruction or neurologic lesion, and without effects on the upper urinary tract. The residue is constant whereas, paradoxically, dysuria may be absent and mictional output normal (8 of the 21 cases). Urodynamic tests distinguished two groups of patients: one in which bladder contractility was still present but decreased rapidly as a function of volume to be excreted, while flow was good; the other in which bladder contractility and flow were altered. Therapeutic possibilities are discussed as a function of results obtained. Depending upon the structural alterations of the bladder wall, medical treatment (cholinergic drugs) are usually ineffective. An interesting solution is the use of abdominal pushes in cases with hypo- or acontractile bladder. Aleatory results of surgery to reduce bladder capacity and/or reinforce bladder contraction suggest its use only as first intention surgery for bladders with retained contractile possibilities. Operations on bladder neck in women carry the risk of incontinence and should be considered only as function of results of other methods, and with the reservation that closure pressure should be at least 80 cm initially. Finally, abstention under surveillance is also an alternative in this context.

Adult↗
PubMed1987

[Urodynamic study of urinary incontinence in women. For what purpose?].

Based on considerable personal experience and a rigorous and critical analysis of case-reports, a highly polemic subject is discussed. This fundamental article, prepared after deliberation and with discernment, is liable to close a debate by sweeping aside certain simplest principles established on bases supposedly scientific to the detriment of clinical observation. Recognition of bladder instability appears to be much more the domain of the an amnesis than of cystometry; transmission failure is a true myth confirmed neither by clinical or surgical findings, and is therefore of no utility for the surgical decision; incontinence due to urgency is perhaps less of an absolute contraindication to surgery than previously considered. It appears artificial to analyze a complex symptom such as urinary incontinence on results of urodynamic data alone, each women possessing a different balance. In contrast, knowledge of certain urodynamic parameters of this balance (particularly closure pressure) can assist prediction of chances of success of surgery. Opponents and proponents of urodynamic exploration of women with urinary incontinence should find in these comments a matter of reflection.

Adult↗
PubMed1987

[Occurrence of IgE-dependent food allergy in asthmatic disease].

The incidence of food allergy has been evaluated in 67 asthmatic patients (allergic asthma: 52, intrinsic asthma: 15). History was positive for post-meals attacks (7), symptoms involving other target organs (61%). Prick tests were found positive in 17/60; intradermal 77/682. Out of 110 human basophil degranulation tests or RAST, performed in 44 patients, 21/15 patients were found positive. Out of 18 inhalation challenges, 7 were positive. Out of 17 food oral challenges, 6 were positive (8 patients). A definite diagnosis of food allergy was accepted for 9 patients. Elimination diet, with 600 mg/day of cromolyn, induced a major improvement in 7 patients within 3 months, with 2 further failures after 1 year. A successful elimination diet was correlated with a positive food challenge. The relative incidence of food allergy in asthmatic adults is discussed (5.8%), as well as a non-immunologic mediated intolerance to food additives in intrinsic asthmatics, the incidence of vegetable allergies in pollen-sensitive patients, the procedures and meaning of inhalation and oral challenges, the relative importance of trophallergens. Food allergy appears to be a variable co-factor in bronchial hyperreactivity.

Asthma↗
PubMed1986

[Cancer of the right kidney and tumor of the right liver].

The true benign nature of a right side of liver tumor was revealed only after postoperative histopathology in a patient with cancer of right kidney. This raises the problem of kidney tumors with liver metastases. The preoperative diagnostic value of liver biopsy under ultrasound guidance is discussed, together with reasonable limits of hepatic excision combined with nephrectomy as a function of single or multiple metastases, their location, and their degree of surgical accessibility.

Aged↗
PubMed1985

[Is iatrogenic vesico-renal reflux a negligible factor in the evolution of recurrent superficial tumors of the bladder?].

The electrocoagulation and resection of superficial tumors of the bladder leads to iatrogenic refluxes. The frequency of subsequent vesical recurrences may thus favor tumoral grafts in the upper urinary tract. Fives cases illustrate this risk. They were treated by ureteral resections and by one bilateral, and two unilateral nephroureterectomies. Should these refluxes be ignored or treated surgically in the event of repeated papillomatous recurrences?

Aged↗
PubMed1985

[Cecocystoplasty. Apropos of 14 cases].

Cystoplasty is the ideal method of bringing back normal urinary flow after cystectomy, and the authors have used this procedure in fourteen cases. The cecum is mobIlized with its vascular pedicle. Bowel continuity is readily and safely restored with the aid of suturing forceps (TA 55, GIA). The cecum is carefully cleaned of all fecal matter. Two UCN join the ureters and the cecum, to which the trigone, the cervix vesicae, or the prostatic or membranous urethra is anastomosed, depending on the case. Three benign cystopathies, four recurrent diffuse papillomatoses and seven vesical carcinomas were treated in this way, with excellent results.

Aged↗
PubMed1977

A nasal functional test: the opeining of mouth during physical effort.

Apart from rare exceptions (cf Voydeville's Thesis, Nancy 1951), nasal airflow resistance has so far been estimated irrespective of variations in air intake needs. The object of the test presented here is to offer a quick, simple and objective method for determining the level of muscular effort at which a given subject spontaneously switches from nasal to buccal respiration. A thin flexible tube (1,5 mm across) is stuck at one end on to the subject's lower lip and the other into a carbon dioxyde analyser. The subject is then made to pedal at a speed at least 30 rev./min. on an ergometric bicycle, while a braking force increasing by 20 W ever two minutes is applied. The emission of carbon dioxyde starts being detected, and graphically recorded, only when the subject starts breathing through his mouth. Results obtained so far show that this threshold can vary as widely as from 80 to 180 W among healthy individuals. Further aplications of this test to both healthy subjects and patients with impaired nasal function would contribute towards throwing light on the still obsure notion of "nasal comfort".

Adult↗