Recurrent abdominal pain in childhood. Relationship to psychological adjustment of children and families: a preliminary study

Chronic abdominal pain in children

Chronic abdominal pain, defined as long-lasting intermittent or constant abdominal pain, is a common pediatric problem encountered by primary care physicians, medical subspecialists, and surgical specialists. Chronic abdominal pain in children is usually functional, that is, without objective evidence of an underlying organic disorder. The Subcommittee on Chronic Abdominal Pain of the American Academy of Pediatrics and the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition has prepared this report based on a comprehensive, systematic review and rating of the medical literature. This report accompanies a clinical report based on the literature review and expert opinion. The subcommittee examined the diagnostic and therapeutic value of a medical and psychological history, diagnostic tests, and pharmacologic and behavioral therapy. The presence of alarm symptoms or signs (such as weight loss, gastrointestinal bleeding, persistent fever, chronic severe diarrhea, and significant vomiting) is associated with a higher prevalence of organic disease. There was insufficient evidence to state that the nature of the abdominal pain or the presence of associated symptoms (such as anorexia, nausea, headache, and joint pain) can discriminate between functional and organic disorders. Although children with chronic abdominal pain and their parents are more often anxious or depressed, the presence of anxiety, depression, behavior problems, or recent negative life events does not distinguish between functional and organic abdominal pain. Most children who are brought to the primary care physician's office for chronic abdominal pain are unlikely to require diagnostic testing. Pediatric studies of therapeutic interventions were examined and found to be limited or inconclusive.

The pressure pain threshold (PPT) of certain muscles in children suffering from recurrent abdominal pain of non-organic origin. An algometric study

The origin of recurrent abdominal pain of "non-organic origin" is believed to be psychogenic in most cases. But the pathogenesis of the pain itself is unknown. To test the hypothesis that recurrent abdominal pain of non-organic origin is related to increased pain sensitivity in the myofascial elements of the abdominal wall itself, an investigation of pain pressure threshold of the abdominal wall, close to the umbilicus, was carried out. Altogether 140 children in the fourth school grade, approximately 11 years old, were tested for pressure pain threshold. Two groups were constituted: one without pain symptoms (no recurrent abdominal pain, chest pains or headache (n = 50)) and one with recurrent abdominal pain (n = 49). The pressure pain threshold differed significantly (p < 0.0001). To support the hypothesis that recurrent abdominal pain is a part phenomenon of a specific pattern of muscular tension and tenderness, the pressure pain threshold was tested in five other muscles, with significant results.

Steady-state kinetic analysis of the quinoprotein methylamine dehydrogenase from Paracoccus denitrificans

A steady-state kinetic analysis was performed of the reaction of methylamine and phenazine ethosulphate (PES) with the quinoprotein methylamine dehydrogenase from Paracoccus denitrificans. Experiments with methylamine and PES as varied-concentration substrates produced a series of parallel reciprocal plots, and when the concentrations of these substrates were varied in a constant ratio a linear reciprocal plot of initial velocity against PES concentration was obtained. Nearly identical values of V/Km of PES were obtained with four different n-alkylamines. These data suggest that this reaction proceeds by a ping-pong type of mechanism. The enzyme reacted with a variety of n-alkylamines but not with secondary, tertiary or aromatic amines or amino acids. The substrate specificity was dictated primarily by the Km value exhibited by the particular amine. A deuterium kinetic isotope effect was observed with deuterated methylamine as a substrate. The enzyme exhibited a pH optimum for V at pH 7.5. The absorbance spectrum of the pyrroloquinoline quinone prosthetic group of this enzyme was also effected by pH at values greater than 7.5. The enzyme was relatively insensitive to changes in ionic strength, and exhibited a linear Arrhenius plot over a range of temperatures from 10 degrees C to 50 degrees C with an energy of activation 46 kJ/mol (11 kcal/mol).

Acinetobacter calcoaceticus genes involved in biosynthesis of the coenzyme pyrrolo-quinoline-quinone: nucleotide sequence and expression in Escherichia coli K-12

Synthesis of the coenzyme pyrrolo-quinoline-quinone (PQQ) from Acinetobacter calcoaceticus requires the products of at least four different genes. In this paper we present the nucleotide sequence of a 5,085-base-pair DNA fragment containing these four genes. Within the DNA fragment three reading frames are present, coding for proteins of Mr 10,800, 29,700, and 43,600 and corresponding to three of the PQQ genes. In the DNA region where the fourth PQQ gene was mapped the largest possible reading frame encodes for a polypeptide of only 24 amino acids. Still, the expression of this region is essential for the biosynthesis of PQQ. A possible role for this DNA region is discussed. Sandwiched between two PQQ genes an additional reading frame is present, coding for a protein of Mr 33,600. This gene, which is probably transcribed in the same operon as three of the PQQ genes, seems not required for PQQ synthesis. Expression of the PQQ genes in Acinetobacter lwoffi and Escherichia coli K-12 led to the synthesis of the coenzyme in these organisms.