Biomedical subjects

R Dionigi

Publications and source records attributed to R Dionigi.

At least 73 records · Page 4Linked to original sources

PubMed1980

Sequential evaluation of immunoreactivity in patients with melanoma undergoing surgery and adjuvant therapy.

The immunologic profile of 15 patients undergoing surgery and adjuvant chemoimmunotherapy for cutaneous melanoma was studied for a mean period of 18 months. In vivo cellular immunity was assayed by evaluation of delayed hypersensitivity response (DHR) to primary antigen and a panel of recall antigens. In vitro cellular immunity was evaluated to means of total and T-lymphocyte counts in peripheral blood and by the lymphocyte blastogenic response to phytohemagglutinin stimulation. Humoral immunity was assayed by determining the serum levels of IgG, IgA and IgM and of complement components C3c, C4 and Factor B. Phagocytic activity was studied by testing leukocyte chemotaxis, neutrophil phagocytosis and leukocyte random migration. The in vitro parameters were determined preoperatively at diagnosis, 6 times during the first 2 postoperative weeks, and then every month during adjuvant therapy. No correlation was found between DHR and clinico-pathologic stage of tumor, or with subsequent clinical course. Significant depression of total lymphocyte and T-lymphocyte count and blastogenic response of lymphocytes was found at diagnosis. The lymphocyte response to PHA decreased significantly in the early postoperative period but returned to preoperative levels one week after surgery. Periodic fluctuations of lymphocyte blastogenic response and progressive decrease of total lymphocyte counts and T-lymphocyte counts were observed during the 18-month follow-up. No significant alterations of immunoglobulin levels were recorded at diagnosis or during the postoperative period. Complement levels were within normal values preoperatively; in the early postoperative period a transient increase of C3c, C4 and Factor B was recorded, then complement levels progressively decreased. Parameters of phagocytic activity were normal at diagnosis and fluctuated within the normal range throughout the whole period of study.

Adult↗

PubMed1979

Clinical-pharmacological aspects, application and effectiveness of total parenteral nutrition in surgical patients.

The term "total parenteral nutrition" (TPN) refers to the maintenance of an adequate nutritional status, normal body weight and positive nitrogen balance solely by intravenous means. It requires solutions providing calories, amino acids and other nutrients in amounts much greater than those indicated for maintenance of normal body weight. Nutrient solutions have been studied, selected and prepared in our Hospital Pharmacological Service utilizing a sterile closed system, which allows large-volume filtering, sterilizing and bottling devices. For maintenance of weight gain in adults, a basic formula is employed, which provides 1,100 Kcal/1 with pure crystalline amino acids mixed with 50% anhydrous dextrose in water in a ratio of 5.8:1 (160 Kcal:1 g nitrogen). Minerals and vitamins are added to the base solution prior to use and may be increased or decreased by simple addition or omission depending on the patient's condition. This paper is based on 192 surgical patients who received TPN and have been followed in strict cooperation between the Hospital Pharmacological Service and the Surgical Department. The patients, ranging from 23 to 79 years of age, with life threatening diseases and unable to maintain adequate nutrition by the oral route, received TPN through a central catheter inserted via subclavian puncture (146 cases) or through a surgically created internal A-V fistula (46 cases). The condition of the patients generally improved within a few days after starting TPN; and weight gain, wound healing, general improvement and a shorter period of hospitalization were observed. TPN could be efficiently combined with oncologic treatment, and a significant improvement of the patients' performance status and decrease of toxic side-effects due to chemotherapeutic agents were observed. TPN has been successfully applied also in patients with fistulas of the alimentary tract obtaining spontaneous closure and in patients with ulcerative colitis, showing its beneficial effect in allowing complete bowel rest for healing. No major complications or deaths could be attributed to TPN or to the route of administration.

Adult↗

PubMed1979

[Myasthenia gravis. Indications, aims and methods of intensive therapy].

Some recent views on pathophisyology of "myasthenia gravis" are presented. The Authors explain the typical damage of myasthenia gravis, i.e. the progressively reduced muscolar function on the basis of an autoimmune derangement affecting the motor-end plates. The most commonly used types of treatment, both medical (i.e. antiChE, A.C.T.H., steroids and immunodepressant drugs) and surgical (thymectomy) are reviewed. The very important role of Intensive Care for the treatment either of myasthenia gravis "per se" or of possible consequences of some drugs (A.C.T.H. steroids) is also stressed. Finally the Authors present their results about their experience on 36 patients affected by myasthenia gravis and admitted to I.C.U. once (29 patients) or twice or more (7 patients). The Authors describe some practical problems presented by patients during their stay in I.C.U.

Adolescent↗

PubMed1978

Postoperative immunologic monitoring of cancer patients undergoing radical surgery.

Immunologic parameters of cellular immunity in vitro and circulating immunoglobulin levels were evaluated before and after radical surgery in twenty-five patients with localized primary solid tumors. Peripheral blood lymphocyte counts, T-lymphocyte counts and lymphocyte blastogenesis after optimal stimulation with phytohemagglutinin were found significantly depressed at the time of diagnosis. Sequential determinations of immunologic parameters during the postoperative period showed a slight fall of lymphocyte counts and T-lymphocyte counts; subsequently these cell counts progressively returned to preoperative values. The blastogenic response of lymphocytes sharply decreased following surgery and then slowly returned to preoperative levels in one month. No significant alterations of circulating immunoglobulins were detected at diagnosis or during the postoperative period. These findings indicate that patients with localized tumors present impairment of some parameters of cellular immunity preoperatively and that postoperative immunodepression lasts about one month.

Adult↗

PubMed1977

The effects of total parenteral nutrition on immunodepression due to malnutrition.

An experimental study was performed in 16 dogs to investigate the effects of sub-acute malnutrition on humoral and cellular immunity and phagocytic functions and, subsequently, to investigate the ability of total parenteral nutrition (TPN) to restore abnormal immunological variables. Deficiencies of IgG, C3, primary immune response to sheep red blood cells (SRBC),lymphocyte counts, lymphocyte response to phytohemagglutinin (PHA), and neutrophi chemotaxis were found to be caused by malnutrition. Nutritional repletion by means of TPN resulted in a return to normal or supranormal serum concentrations of IgG, IgM, and C3, and the primary immune response to SRVC was prompter and higher. Moreover, TPN resulted in restoration of normal neutrophil chemotactic responses. TPN did not improve lymphocyte response to PHA in these experiments. The study demonstrates that subacute malnutrition results in broad based deficiencies of the immunological response of the type that predispose to infection and that the proper use of TPN can correct most of these abnormalities.

Animals↗

PubMed1976

Histopathological studies on dog lymphoid structures during malnutrition and total parenteral nutrition.

Lymphoid tissues of six malnourished dogs were histologically evaluated and compared to the same lymphoid structures of dogs nutritionally repleted by means of total parenteral nutrition (TPN). The results show that thymus, spleen, lymph nodes and Peyer's patches are markedly atrophic and severely cell depleted in malnourished dogs, and provide evidence that subsequent TPN therapy stimulates and supports lymphoid cell prolipheration, leading to cell repopulation of previously depleted lymphoid structures.

Animals↗

PubMed1975

Cardiac muscle models for both isotonic and isometric contractions.

The choice of a suitable muscle model consistent with the mechanical behaviour of Rat papillary muscle at rest or during isotonic or isometric contraction has been considered. Three different preload levels within the ascending limb of the Frank-Starling curve have been used in five papillary muscles. Series elastic (SE) and parallel elastic (PE) length-tension relationships have been evaluated according to five mechanical muscle models using data from systolic and diastolic quick-release manoeuvres. For each preload level and muscle model, the time course of the force-velocity relationship of the contractile element (CE) has been calculated using a PDP 8/L digital computer. Several mechanical and biological characteristics are considered which exclude four of the five selected muscle models. The Maxwell model with a damper seems to be the most suitable mechanical model for Rat papillary muscle. According to the selected muscle model it seems that VCEmax is dependent on muscle length variation; the reliability of this parameter as an index of myocardial contractility is discussed.

Animals↗

PubMed1974