Biomedical subjects

M M Garriga

Publications and source records attributed to M M Garriga.

6 recordsLinked to original sources

PubMed1991

A combined single-blind, double-blind, placebo-controlled study to determine the reproducibility of hypersensitivity reactions to aspartame.

Aspartame is an O-methyl ester composed of phenylalanine and aspartic acid. After its final approval as a sweetener in 1981, a number of reports of adverse reactions to aspartame appeared in the literature. To explore the pathogenesis of such reactions, we initiated a study in July 1986 to identify subjects with hypersensitivity reactions to aspartame with blinded challenge procedures. The study was closed after 32 months. During that time, we advertised in local newspapers and worked closely with the local community of allergists and dermatologists in an attempt to recruit subjects with hypersensitivity reactions to aspartame. A total of 61 self-referrals and physician referrals were screened, with 20 referrals evaluated in clinic. After this evaluation, 12 patients underwent single- and double-blind challenge with up to 2000 mg of aspartame. No subject with a clearly reproducible adverse reaction to aspartame was identified. In summary, we found that it is difficult to recruit study subjects with a history of hypersensitivity reactions to aspartame and that subjects who believed themselves allergic to aspartame did not have reproducible reactions.

Adult↗

PubMed1990

Mast cells in cutaneous mastocytosis: accumulation of the MCTC type.

Lesional (n = 15) and non-lesional (n = 10) skin of subjects with mastocytosis was analysed for the distribution and concentration of trypase positive, chymase negative mast cells (MCT) and tryptase positive, chymase positive mast cells (MCTC) cells and compared to normal skin (n = 23) and non-lesional skin of subjects with unexplained anaphylaxis or flushing episodes (n = 6). Skin biopsies were fixed in Carnoy's fluid and subjected to double immunohistochemical staining with biotinylated mouse monoclonal anti-chymase antibody followed by alkaline phosphatase-conjugated mouse monoclonal anti-tryptase antibody. MCTC cells were the only type of mast cells seen in all specimens analysed and in each case were more numerous in superficial compared to deep regions of dermis. The concentration (mean +/- s.d.) of mast cells in the superficial dermis of mastocytosis lesions (40 985 +/- 21 772 mast cells/mm3) was significantly increased over that in corresponding areas of non-lesional skin from subjects with mastocytosis (7178 +/- 3607 mast cells/mm3), skin from subjects with idiopathic anaphylaxis or flushing episodes (6974 +/- 3873 mast cells/mm3) and normal skin (7347 +/- 2973 mast cells/mm3). The exclusive presence of MCTC cells in skin lesions of mastocytosis which are characterized by non-malignant hyperplasia of mast cells suggests involvement of local tissue factors in mast cell recruitment and differentiation.

Biopsy↗

PubMed1989

The histamine content of oriental foods.

Several of the symptoms of scombroid poisoning (i.e. histamine toxicity) resemble those observed in people suffering from Chinese restaurant syndrome. Therefore, the histamine content of representative Chinese cuisine, which included 31 common dishes, 12 condiments and 12 basic ingredients from several sources, was measured using a sensitive and specific radioenzymatic assay. A further enzymatic procedure involving diamine oxidase was used to verify that the substance measured was histamine. A total of 184 assays were performed on 57 samples in the study. High levels of histamine were found in the cheeses, which were used as positive controls (863.6 micrograms histamine/g blue cheese and 107.4 micrograms histamine/g Parmesan cheese), and in some common condiments, including tamari (2392.2 micrograms histamine/g sample) and one brand of soy sauce (220.4 micrograms histamine/g sample). The histamine content of four condiments and three common dishes was over 10 micrograms histamine/g sample, while four condiments and 16 common dishes contained less than 1 microgram histamine/g sample. Calculations involving representative amounts of food that can be consumed at a typical oriental meal suggest that, in some cases, histamine intake may approach toxic levels. The results are discussed with regard to the possible role of histamine in reactions associated with restaurant meals.

Animals↗

PubMed1988

A survey of the number and distribution of mast cells in the skin of patients with mast cell disorders.

It has been suggested that patients who present with episodes of unexplained anaphylaxis (UEA) or unexplained flushing (UEF) have systemic mastocytosis (SM), a proposal believed to be supported by the presence of excess mast cell (MC) numbers in the skin of these individuals. To examine this hypothesis, we determined the number and distribution of MCs in the skin of nine normal subjects, nine patients with UEA/UEF, six patients with urticaria pigmentosa (UP), and 14 patients with SM. Skin biopsy specimens of normal subjects contained 38.4 +/- 4 (mean +/- SEM) MCs per square millimeter. Biopsy specimens of patients with UEA/UEF contained 71.8 +/- 13 MCs per square millimeter. Although the numbers were significantly different from numbers in skin of normal subjects (p less than 0.05), similar modest increases in MC numbers are observed in a number of skin conditions. In marked contrast, lesional biopsy specimens of patients with UP contained 596.5 +/- 278 MCs per square millimeter (p less than 0.05, n = 6, compared to MC numbers in the skin of normal subjects), and patients with SM had 720.6 +/- 176 MCs per square millimeter in lesional skin (p less than 0.01, n = 12, compared to normal skin). Patients with UP or SM also had increased MC numbers in nonlesional skin compared to normal skin (168.0 MCs per square millimeter, p less than 0.05, n = 5, and 184.4 MCs per square millimeter, p less than 0.01, n = 10, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Histamine↗

PubMed1988

Aspartame intolerance.

Aspartame is a food additive marketed under the brand name Nutrasweet. Aspartame is a white, odorless, crystalline powder and consists of two amino acids, L-aspartic acid and L-phenylalanine. It is 180 times as sweet as sugar. The Food and Drug Administration (FDA) first allowed its use in dry foods in July 1981 and then approved its use in carbonated beverages in July 1983. It has subsequently been approved for use in a number of materials including multivitamins, fruit juices, stick-type confections, breath mints, and iced tea. The FDA requires the statement "phenylketonurics: contains phenylalanine" on labels of food products containing aspartame because individuals with phenylketonuria (PKU) must restrict their intake of phenylalanine. Aspartame is judged to be free of long-term cancer risks. Aspartame is not stable under certain conditions including baking and cooking, and prolonged exposure to acid conditions. In such situations it loses its sweetness. Products formed from aspartame include its component amino acids (phenylalanine and aspartic acid), methanol, and diketopiperazine (DKP). Animal studies show DKP to be nontoxic. Methanol occurs in small amounts and does not exceed that formed during consumption of many foods including fresh fruits and vegetables. FDA's Center for Food Safety and Applied Nutrition (CFSAN) monitors aspartame's safety in part through reports of adverse reactions. After aspartame was approved for use in carbonated beverages, the FDA received an increased number of reports concerning adverse reactions related to aspartame. The Centers for Disease Control (CDC) reviewed these reports, which included complaints of neurologic, gastrointestinal, andallergic reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Aspartame↗

PubMedDate not supplied

Mastocytosis in infants and children: recognition of patterns of skin disease.

Mastocytosis is a disease characterized by an increase in the number of tissue mast cells and a concomitant increase in mast cell-derived mediators. To demonstrate the spectrum of skin disease in mastocytosis in the pediatric population, five children with mastocytosis and complaints of urticaria (4/5), bullae/vesicles (3/5), abdominal pain (3/5), flushing (2/5), headache (1/5), and bone pain (1/5) are reviewed. Confirmation of the diagnosis of cutaneous mastocytosis was obtained by histologic examination of a biopsy of lesional skin; however, mast cell numbers in lesional skin did not correlate with plasma histamine levels or the extent of cutaneous involvement. Mastocytosis is a diagnosis that must be recognized in the differential diagnosis of pediatric urticarial diseases.

Adult↗