Biomedical subjects

M Giasson

Publications and source records attributed to M Giasson.

10 recordsLinked to original sources

PubMed1998

Effect of therapeutic touch on the well-being of persons with terminal cancer.

The purpose of this study was to examine the effect of three Therapeutic Touch treatments on the well-being of 20 persons with terminal cancer in palliative care. Participants in the experimental group (n = 10) received three noncontact Therapeutic Touch treatments, the duration of which varied between 15 to 20 minutes. Participants in the control group (n = 10) participated in three rest periods. Well-being was measured at preintervention time and immediately postintervention time using the Well-Being Scale, a visual analogue scale measuring pain, nausea, depression, anxiety, shortness of breath, activity, appetite, relaxation, and inner peace. The results of the study support the hypothesis that three noncontact Therapeutic Touch treatments increase sensation of well-being in persons with terminal cancer.

Adult↗

PubMed1997

Colonic transit time after spinal cord injury.

Colonic transit time (CTT) was measured with abdominal radiographs using Chaussade's technique in 30 spinal cord injured patients (ASIA A and B) following ingestion of 20 radiomarkers per day for three days. A significant increase in total CTT (p = 0.0001) and segmental CTT of the right colon (p = 0.0004) and of the left colon (p = 0.0001) was shown. While using on the average only 2.3 films of the abdomen per patient, we obtained results comparable with other radiologic techniques which use radiomarkers to measure CTT. The clinical relevance of these results is not clear and their correlation with intestinal symptoms remains to be investigated.

Adolescent↗

PubMed1996

Multiple nuclear regulatory proteins bind a single cis-acting promoter element to control basal transcription of the human alpha 4 integrin gene in corneal epithelial cells.

Expression of the fibronectin-binding integrin alpha 4 beta 1 has been postulated to be an important event in the process of corneal epithelial wound healing. In a previous study, we identified upstream positive and negative cis-acting regulatory elements that are needed to modulate the transcriptional activity of the human alpha 4 integrin subunit gene promoter in primary cultures of rabbit corneal epithelial cells. We have shown that most of the basal activity directed by this promoter was dependent on the presence of a cis-acting DNA sequence designated the alpha 4.1 element, centered at position -45 relative to the human alpha 4 mRNA start site. Here, we demonstrate that five distinct nuclear regulatory proteins (designated Bp1 to Bp5) from rabbit corneal epithelial cells possess the ability to bind the alpha 4.1 element in a specific manner in vitro. However, when they are combined together, only two of them (Bp2 and Bp5) retained their ability to interact with their specific target sequence in in vitro assays. The apparent molecular masses of the Bp1 to Bp5 proteins were determined and found to be of 91, 74, 59, 45, and 39 kD, respectively. Electrophoretic mobility-shift assays (EMSAs) indicated that only Bp2 also possesses the ability to bind the alpha 4.2 element, a site homologous to alpha 4.1 which plays a minor role in alpha 4 gene expression. Despite the presence of three Ets binding sites in the immediate vicinity of alpha 4.1, competition experiments in EMSA clearly indicate that Bp1, Bp2, Bp4, and Bp5 do not belong to the Ets family of transcription factors. Insertion of both alpha 4.1 and alpha 4.2 upstream from the basal promoter of the mouse p12 gene provided evidence that both elements have the ability to modulate basal expression driven from a heterologous promoter. alpha 4.1 was shown to function as an activator, whereas alpha 4.2 acted as a repressor in a manner that is dependent on its orientation, further stressing the critical regulatory function played by these two elements on alpha 4 gene basal expression.

Animals↗

PubMed1993

Effects of EGF, IL-1 and their combination on in vitro corneal epithelial wound closure and cell chemotaxis.

We investigated the effects of EGF, IL-1 and their combination on closure of wounds inflicted on rabbit corneal epithelial cell cultures and on migration of these cells in microchemotaxis chambers. In vitro corneal epithelial wound closure depended on the applied concentrations of EGF or IL-1. Twenty-four hours after wounding, the smallest wounds were obtained with 50 ng ml-1 of EGF and 1 ng ml-1 of IL-1, respectively. The effect on wound closure of combinations of EGF and IL-1 was additive even at concentrations that were optimal for each growth factor when applied alone. We found that EGF increases the chemotactic migration of rabbit corneal epithelial cells. Cell chemotaxis depended both on the concentration of EGF and on the number of cells applied in the assay. This response to EGF was seen at concentrations that were effective in the wound closure assay. The magnitude of the chemotactic migration response was much smaller with IL-1 than with EGF. Similarly to the observations on wound closure, the effect on cell chemotaxis of combinations of EGF and IL-1 was additive. The ability of EGF, and EGF/IL-1 combinations to modulate corneal epithelial cell chemotactic migration supports migration as a possible biological mechanism of the acceleration of corneal epithelium wound closure by these drugs.

Animals↗

PubMed1990

Topical fibronectin and aprotinin for keratectomy wound healing in rabbits.

We evaluated the effect of fibronectin (an adhesive protein) and aprotinin (a protease inhibitor) as single or combined topical therapies for primary healing and prevention of recurrent corneal epithelial defects in the rabbit keratectomy wound model. The biological activity of the prepared solutions of rabbit plasma fibronectin (0.6 g/L) was suggested by in vitro assays of rabbit corneal epithelial cell adhesion and gelatin-binding affinity. In the first experiment, we compared fibronectin, albumin (a control nonadhesive protein), and saline. In the second and third experiments, fibronectin supplemented with aprotinin, aprotinin alone, and saline were compared; aprotinin was used at concentrations of 40 and 1000 kallikrein inactivating units (KIU) per mililiter. Our results suggest that topical fibronectin, 0.6 g/L, as well as aprotinin at 40- and 1000-KIU/mL concentrations, given alone or in combination, neither promote corneal epithelial wound healing nor prevent recurrent corneal epithelial defects in rabbit keratectomy wounds.

Administration, Topical↗

PubMed1988

Plasma levels of hydroxy-flutamide in patients with prostatic cancer receiving the combined hormonal therapy: an LHRH agonist and flutamide.

The present study describes a method for the measurement of the plasma levels of hydroxy-flutamide (Flu-OH), the biologically active and main circulating metabolite of flutamide. We have observed that two to four hours after oral administration of 250 mg of flutamide to healthy young men, as well as to patients with prostate cancer, the plasma concentration of Flu-OH reaches a peak at approximately 1.7 microM. The plasma concentration of Flu-OH measured at months 6, 12, and 18 of treatment shows a minimal basal level of 3.4 microM with a maximal increase at 6.8 to 8.5 microM at 2 to 4 hours. Since the serum levels of testosterone in these patients are approximately 1 nM, the levels of the active antiandrogen are at a 5000- to 10000-fold excess. However, due to the low affinity of the antiandrogen for the androgen receptor, it is extremely important to maintain this concentration of the antiandrogen in plasma constant.

Adult↗

PubMed1985

Serum immunoglobulin levels following allogeneic bone marrow transplantation.

In order to study the posttransplant evolution of serum immunoglobulin levels, we measured serum IgG, IgA and IgM levels in 50 recipients of allogeneic bone marrow before transplantation and at different intervals thereafter (days 39, 120, 365 and 730). IgG and IgM levels were depressed for 1 year and IgA levels for 2 years posttransplant. Immunoglobulin deficiency was more severe and prolonged in patients with graft versus-host-disease. Hypogammaglobulinemia may contribute to the frequent infections observed in these patients, especially those with chronic graft-versus-host disease.

Adolescent↗

PubMed1984

Selective inhibition of spermatogenesis in the presence of normal libido following combined treatment with an LHRH agonist and testosterone in the dog.

In order to maintain libido in dogs treated with an LHRH agonist, animals were administered with testosterone in a gel form for percutaneous adsorption. Histological aspect of testis indicate a complete blockade of spermatogenesis after treatment with the LHRH agonist and the addition of testosterone to these animals did not restore the spermatogenesis. The measurement of testicular steroid levels showed that following LHRH-A administration, the concentration of androgens in testis remained low in the presence or absence of testosterone supplement. However, the prostate weight as well as the volume of ejaculate returned to normal when testosterone was added and this observation can be correlated with the high amount of androgens in prostate. The present study supports the use of LHRH agonist in combination with testosterone as a selective method for inhibition of spermatogenesis in the male.

Animals↗

PubMedDate not supplied

Reconstructed human cornea produced in vitro by tissue engineering.

The aim of the present study was to produce a reconstructed human cornea in vitro by tissue engineering and to characterize the expression of integrins and basement membrane proteins in this reconstructed cornea. Epithelial cells and fibroblasts were isolated from human corneas (limbus or centre) and cultured on plastic substrates in vitro. Reconstructed human corneas were obtained by culturing epithelial cells on collagen gels containing fibroblasts. Histological (Masson's trichrome staining) and immunohistological (laminin, type VII collagen, fibronectin as well as beta1, alpha3, alpha4, alpha5, and alpha6 integrin subunits) studies were performed. Human corneal epithelial cells from the limbus yielded colonies of small fast-growing cells when cultured on plastic substrates. They could be subcultured for several passages in contrast to central corneal cells. In reconstructed cornea, the epithelium had 4-5 cell layers by the third day of culture; basal cells were cuboidal. The basement membrane components were already detected after 3 days of culture. Integrin stainings, except for the alpha4 integrin, were also positive after 3 days. They were mostly detected at the epithelium-stroma junction. Such in vitro tissue-engineered human cornea, which shows appropriate histology and expression of basement membrane components and integrins, provides tools for further physiological, toxicological and pharmacological studies as well as being an attractive model for gene expression studies.

Cell Division↗

PubMedDate not supplied

[Therapeutic touch].

In the advanced stages of dementia of the Alzheimer's type (DAT), affected persons present body language and various behaviours expressing discomfort: shouting, agitation, irritability, aggressiveness, tense movements. Nursing, up until now, has had few available means to ease this discomfort. The authors of the following article have conducted an experimental study measuring the alleviating effects of therapeutic touch on the discomfort of persons in the advanced stages of DAT. Experimental group subjects (n = 16) received 5 sessions of therapeutic touch lasting 12.4 minutes. Control group subjects (n = 11) received 5 sessions of simple presence lasting 10.3 minutes. The authors measured subject discomfort levels using the Discomfort Scale for Dementias of the Alzheimer's Type (DS-DAT). Results show that discomfort levels of persons in the advanced stages of DAT decreased significantly after 5 therapeutic touch sessions, becoming significantly lower than levels in the control group. If care was focused on the whole person and his or her comfort, tools like therapeutic touch would become available to nurses, allowing them to enhance the quality of life of the people in their care.

Aged↗