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J A Gould

Publications and source records attributed to J A Gould.

15 recordsLinked to original sources
PubMed2001

Identification and characterization of alternatively spliced murine Rgs11 isoforms: genomic structure and gene analysis.

The RGS proteins comprise a large family of proteins which were recently identified as negative Regulators of G-protein Signaling. They have been shown to act as GTPase Activating Proteins (GAPs) towards the G(alpha) subunits of heterotrimeric G-proteins. In addition to this GAP activity, which has been shown to occur through the RGS domain, RGS proteins are likely to possess other functions due to the existence of other domains in these molecules (De Vries and Farquhar, 1999; Hepler, 1999). Here, we report the molecular characterization of the murine Rgs11 gene. The gene encodes a protein with high homology to human RGS11 (79.9%), containing conserved DEP (Dishevelled/EGL-10/Pleckstrin) and GGL (G protein gamma-like) domains. The gene is comprised of at least 13 exons, spanning 8-9 kb. Spliced transcript variants were identified which are co-expressed with 5A3, a transcript that contains the largest ORF. Expression of mouse Rgs11 was found to be restricted to specific tissues with a unique pattern of expression observed in brain.

Alternative Splicing↗
PubMed2000

Methylation-dependent silencing of the testis-specific Pdha-2 basal promoter occurs through selective targeting of an activating transcription factor/cAMP-responsive element-binding site.

In this study, we demonstrate that methylation-dependent repression of the Pdha-2 core promoter is mediated regionally through a consensus activating transcription factor/cAMP-responsive element-binding site located between nucleotides -54 and -62 upstream of the major transcriptional start site. Targeting of the CpG dinucleotide within this cis-element significantly disrupts the ability of this basal promoter to activate gene expression in vitro and completely abolishes promoter activity in vivo. DNase I footprinting experiments indicated that availability of the nuclear factor(s) binding this element is limiting in sexually immature mouse testis, and as such, these factors may play an important role in the coordinate activation of early spermatogenic gene expression. Interestingly, CpG dinucleotides associated with the hypersensitive region flanking the activating transcription factor/cAMP-responsive element-binding site appear to confer some conformational structure on the promoter since mutations at these specific CpG dinucleotides result in elevated basal levels of transcription. This raises the possibility of a potential bifunctional role for CpG dinucleotides in either methylation-dependent or -independent processes. Our data support the notion that hypomethylation and transcription factor recruitment are necessary events that precede gene activation at the early stages of spermatogenesis.

3T3 Cells↗
PubMed1991

Interleukin-2 and high-dose cisplatin in patients with metastatic melanoma: a pilot study.

In this pilot study of metastatic melanoma, interleukin-2 (IL-2) and cisplatin (CDDP) chemotherapy were combined using an alternating schedule designed to explore potential synergism between these modalities. Bolus IL-2 was given at a dose of 600,000 IU/kg intravenously (IV) every 8 hours, days 1 to 5 and 15 to 19, followed by high-dose CDDP administered by two different regimens: (A) 135 to 150 mg/m2 IV bolus over 30 minutes with the chemoprotectant WR-2721 910 mg/m2 or (B) 50 mg/m2 IV over 2 hours every day for 3 days. The trial design allowed an assessment of response to each phase of therapy. Among 27 assessable patients, there were 10 (37%) overall responses, including three (11%) complete responses (CRs) with durations of 9, 16, and 30+ months. Tumor regression was noted in seven patients (partial response [PR], four; minor response [MR], three; response rate [RR], four of 27 [15%]) after IL-2 administration and in 14 patients (PR, 12; MR, two; RR, 12 of 27 [44%]) after CDDP treatment, demonstrating noncrossresistance between the components of the regimen. Major PRs (greater than 90% reduction of tumor burden) or CRs were only seen in patients responding to IL-2. Toxicity during IL-2 therapy was typical for high-dose IL-2 protocols and was reversible. Among the first 20 patients treated with CDDP regimen A, there were eight episodes of grade IV nephrotoxicity (creatinine level greater than 5.0 mg/dL), including three of six patients treated with an initial CDDP dose of 135 mg/m2. This side effect was more frequent among patients with liver metastasis (P less than .05, Fisher's exact test). No significant nephrotoxicity was noted in seven patients treated on regimen B. Although ototoxicity was frequent, minimal bone marrow and neurologic toxicity was noted. There were no treatment-related deaths. This combination showed at least additive activity against melanoma, and the more protracted CDDP schedule was well tolerated. This regimen may serve as a model for future combined immunotherapy and chemotherapy trials in metastatic melanoma.

Adult↗
PubMed1991

Procurement and transplantation of colonized cadaver skin.

Cadaver skin is an important adjunct to burn care. This study was designed to measure the percentage of its contamination prior to grafting and to determine the clinical safety of its use. Cadaveric homografts from 19 donors were harvested, frozen, thawed, and used as a biological dressing. Cultures were obtained at the time of harvest, after incubation in antibiotics, and at actual transplantation. The homografts were 43 per cent, 68 per cent, and 50 per cent contaminant-free, respectively. Two of 14 patients lost their homografts due to infection. However, no patient developed an infection or lost the homograft due to an organism identified during the pretransplantation processing. Therefore, contaminant-free and slightly contaminated cadaver skin can be used safely as homografts.

Adolescent↗
PubMed1990

Nosocomial sepsis associated with interleukin-2.

STUDY OBJECTIVE: To determine the incidence, clinical magnitude, and risk factors for nosocomial bacteremia in patients given interleukin-2 with or without (+/-) lymphokine activated killer (LAK) cells for cancer immunotherapy. DESIGN: Cohort study. SETTING: Clinical study unit of tertiary medical center. PATIENTS: All patients entering the interleukin-2 +/- LAK cancer immunotherapy protocol during a 28-month period. Control groups were patients in a surgical intensive care unit, patients receiving total parenteral nutrition, and patients with solid tumors. MEASUREMENTS AND MAIN RESULTS: Twenty of 107 (19%) interleukin-2-treated patients developed sepsis; in 12 of these patients, sepsis was intravenous catheter-associated. The bacteremia rate among patients receiving total parenteral nutrition, in the surgical intensive care unit, or having solid tumors was 2.8%, 4.1%, and 1.9%, respectively. Staphylococcus aureus was the pathogen in 13 courses; Staphylococcus epidermidis, in 5; and Escherichia coli, in 2. Two patients died; three developed suppurative thrombophlebitis; one developed septic arthritis; one, septic arterial aneurysm; and one, peritonitis with probable meningitis. Colonization with S. aureus increased the risk of S. aureus bacteremia 6.3-fold (95% CI, 2.8 to 14.5; P less than 0.001); skin desquamation at the catheter site increased the relative risk 2.0-fold (95% CI, 1.3 to 3.1; P = 0.031). Both colonization with S. aureus and skin desquamation increased the relative risk of S. aureus bacteremia 14.5-fold (95% CI, 4.1 to 50.9; P less than 0.0001). CONCLUSIONS: Staphylococcal bacteremia is more frequent in patients receiving interleukin-2 therapy and is associated with substantial morbidity and toxic skin reactions.

Adult↗
PubMed1988

Hypothyroidism after treatment with interleukin-2 and lymphokine-activated killer cells.

The development of a goiter and hypothyroidism in a 28-year-old man in whom metastatic melanoma had been treated with interleukin-2 and lymphokine-activated killer cells (LAK cells) prompted us to assess thyroid function in patients undergoing this therapy. Thirty-four patients with advanced neoplasms who had received interleukin-2 and LAK cells were followed for at least four weeks after treatment. Seven patients (21 percent) had laboratory evidence of hypothyroidism, with a decline in the serum thyroxine concentration to below normal (less than or equal to 35 nmol per liter; normal, 65 to 148), a decline in the serum free thyroxine index, and a rise in the serum thyrotropin concentration (peak values, 7.2 to 166 mU per liter; normal, 0.5 to 5.5) 6 to 11 weeks after treatment. Two patients had elevated serum thyrotropin levels before treatment, which increased further after treatment. In two patients, these abnormal values returned to normal within 10 months. All five symptomatic patients had borderline or elevated serum antimicrosomal antibody titers after treatment; two had serum antibodies to thyroglobulin. Five of the seven patients with hypothyroidism (71 percent) but only 5 of the 27 euthyroid patients (19 percent) had evidence of tumor regression (P less than 0.02). None of 11 patients treated with interleukin-2 but not LAK cells had hypothyroidism. We conclude that treatment with interleukin-2 and LAK cells can cause hypothyroidism, possibly by exacerbating preexisting autoimmune thyroiditis, and that it may be associated with a favorable tumor response.

Adult↗
PubMed1987

Studies of short-term secretion of peptides produced by alternative RNA processing.

Alternative RNA processing of the calcitonin gene primary transcript results in production of two peptides, calcitonin and calcitonin gene-related peptide (CGRP). We have used the TT cell line, which produces both peptides, to ascertain whether secretion of peptides produced by alternative RNA processing is under identical regulatory control. Short-term treatment of TT cells with phorbol esters and cAMP analogs caused a rapid and parallel release of both calcitonin and CGRP. The measurement of calcitonin and CGRP mRNA levels during treatment revealed that new RNA synthesis was not required for secretion. Four potential regulators of phorbol ester-mediated and five of cAMP-mediated secretion were identified by incorporation of radioactive phosphate into protein as analysed by two-dimensional polyacrylamide gel electrophoresis and autoradiography. From these results we conclude that calcitonin and CGRP secretion in this human C cell model is not differentially affected by alternative RNA processing for the phorbol ester-, and cAMP-dependent secretory pathways.

Calcitonin↗
PubMed1986

Phase I evaluation of recombinant interleukin-2 in patients with advanced malignant disease.

Seventeen patients with refractory malignant tumors were treated with recombinant human interleukin-2 (IL-2) administered by weekly bolus intravenous (IV) injection in a phase I dose escalation trial. Patients received 10,000 to 1,000,000 U/m2 per injection over a course of 3 to 33 weeks. Toxicity was dose related and consisted primarily of fever, chills, nausea, and vomiting. Hypotension was observed at doses of 500,000 U/m2 or higher and in one instance was sufficiently severe to require pressors. No tumor regression was seen and all patients eventually developed progressive disease. Blood levels of cortisol, ACTH, prolactin, and growth hormone as well as the acute phase reactant C-reactive protein (CRP) increased after the administration of IL-2 in most patients. Serum IL-2 levels in excess of 250 U/mL were detected five minutes after an IV injection of 1,000,000 U/m2, after which the levels declined with a half-life of approximately 25 minutes. No alteration in lymphocyte surface phenotype or enhancement in natural cell-mediated cytotoxicity against natural killer (NK)-sensitive and resistant tumor cell lines was observed when these parameters were measured weekly just before the IL-2 injections. However, a dramatic but transient decline in circulating lymphocytes and NK activity was noted within hours of receiving IL-2. This effect was independent of fever and was not abrogated by pretreatment with ibuprofen or metyrapone. The majority of patients developed serum IgG antibodies of IL-2 detectable with a sensitive enzyme-linked immunosorbent assay (ELISA) and a nitrocellulose dot blot assay. The development of anti-IL-2 antibodies was not associated with symptoms suggestive of serum sickness, reductions in serum complement levels, or deterioration in lymphocyte tumoricidal activity. This investigation provides insight into the in vivo actions of this potent biological response modifier and will assist in the design of future studies with IL-2 administered alone or in conjunction with other treatment modalities.

Adult↗
PubMed1985

Toxicity episodes involving agricultural chemicals and other substances in birds in Victoria, Australia.

A series of case reports detailing observations on toxicity episodes in birds caused by a variety of agricultural chemicals and other substances is presented. These problems arose as a result of ignorance, accident and malicious intent. The episodes involved maldison, monocrotophos, fenitrothion, trichlorofon, dieldrin, chlordane, endrin, metaldehyde, bromadiolone, arsenic, lead and zinc. An unresolved episode where toxicity was implicated is also included.

Animals↗
PubMed1984

Pancreatic degeneration in broilers with runting and stunting syndrome.

A number of plasma biochemical parameters were examined in five outbreaks of runting in broiler chickens. In four of the five outbreaks, runts showed consistent elevations in plasma amylase activity and reductions in glutathione peroxidase activity. In two of the five outbreaks the plasma vitamin E concentration was reduced, as was the activity of plasma alkaline phosphatase. A highly significant number of runted chickens were found to have pancreatic degeneration, elevated plasma amylase activity and reduced plasma glutathione peroxidase activity, compared with non-runted chickens. The implications of these changes are discussed in relation to the aetiology of runting and stunting syndrome and, in particular, the possible involvement of selenium.

Alkaline Phosphatase↗
PubMed1982

Studies on a vaccine against infections bursal disease.

An infectious bursal disease vaccine, registered for use in breeder flocks, was studied for efficacy on the day-old offspring of vaccinated hens and for virulence in susceptible day-old and 6-week-old chickens. When given to susceptible day-old chicks and 6-week-old cockerels, the vaccine was found to induce atrophy and pathology of the bursa of Fabricius similar to that observed in field infections. Chicks vaccinated at day-old had markedly lowered titres in the haemagglutination inhibition test to Newcastle disease virus, when this was given 2 weeks later, but the response of the 6-week-old cockerel was similar to that of control birds. Maternal antibody induced by the vaccine protected chicks against infection at day-old.

Animals↗
PubMedDate not supplied

Review: Pdha-2, past and present.

Pyruvate dehydrogenase (PDH) is a multiunit enzymatic complex essential for the process of generating cellular energy. One of the most important of its subunits is the E1 alpha subunit. Perturbations in the expression of this subunit lead to reduced or lost function of the PDH complex as a whole, resulting in a loss of ATP production. The consequence of such perturbations can lead to neurological abnormalities, lactic acidosis, and in males, death. Pdha-2 codes for the mouse testis isoform of the E1 alpha subunit and maps to chromosome 19 (chromosome 4 in humans). This is a fortuitous evolutionary development because the somatic isoform of the E1 alpha subunit is linked to the X-chromosome, which is not only inactivated early in spermatogenesis but is represented in only half of the haploid spermatid population. Consequently, activation of the testis-specific E1 alpha subunit is essential for the progression of spermatogenesis. Despite its importance, the molecular mechanisms governing the tight tissue- and temporal-specific regulation of Pdha-2 have, until recently, remained poorly understood. In this review, we describe our current understanding of the transcriptional regulation of Pdha-2 and propose potential mechanisms that may play a role in this process.

Adenosine Triphosphate↗