Assessment of the effectiveness of low-level laser therapy on the hands of patients with rheumatoid arthritis: a randomized double-blind controlled trial.

Assess the effectiveness of low-level laser therapy on pain reduction and improvement in function in the hands of patients with rheumatoid arthritis. A randomized double-blind controlled trial was carried out on 82 patients with rheumatoid arthritis. The experimental group was submitted to the application of laser therapy, whereas the control group received a placebo laser. Aluminum gallium arsenide laser was used, at a wavelength of 785 nm, dose of 3 J/cm(2) and mean power of 70 mW. The groups were homogenous at the beginning of the study with regard to the main variables (p > 0.05). There were no statistically significant differences between groups in most of the measurements taken at the end of the intervention including the primary variables; the following variables were the exceptions: favoring the experimental group-inflammation of the interphalangeal joint of the right thumb (p = 0.012) and perimetry of the interphalangeal joint of the left thumb (p = 0.013); and favoring the control group-flexion of the proximal interphalangeal joint of the right fifth finger (p = 0.021), perimetry of the third proximal interphalangeal joint of the right hand (p = 0.044), grip strength in the left hand (p = 0.010), and the work domain of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire (p = 0.010). We conclude that low-level aluminum gallium arsenide laser therapy is not effective at the wavelength, dosage, and power studied for the treatment of hands among patients with rheumatoid arthritis.

In vitro assessment of antacid efficacy using a computer-controlled 'artificial stomach-duodenum' model reproducing gastroduodenal flux regulation.

We have developed an artificial stomach-duodenum model made up of three compartments representing the stomach, (including a fragment of hog gastric mucosa), the proximal duodenum, and the distal duodenum. Gastroduodenal flow rates are controlled by a microcomputer capable of (1) adjusting gastric emptying and alkaline secretion in the proximal duodenum according to intragastric pH; (2) adjusting pancreatic alkaline secretion according to proximal duodenum pH; and (3) simulating acid response to food ingestion. Antacid drugs were added 90 min after simulated food ingestion in near-physiological or duodenal ulcer conditions. Aluminum phosphate-containing antacids resulted in a persistent antacid effect, due to their adsorption to the gastric mucosa; this prolonged the buffering capacity at pH 2.4 to 120 min. Aluminum+magnesium hydroxides and calcium+magnesium carbonate combinations mainly exerted neutralizing activity, inducing an increase in the gastric emptying rate. In the duodenal ulcer simulation, the pH of the gastric contents was lower and the antacid effect was shorter than in the 'physiological' simulation.

Assessment of mucus glycoprotein erosion by measurement of sialic acid in gastric secretions: pathophysiologic and therapeutic aspects.

The quantification of mucus glycoproteins (GPs) faces paramount difficulties in terms of methods and interpretation. Mucus glycoprotein erosion, however, might be quantified in gastric juice by measurement of GP-bound sialic acid. Basal sialic acid content was low in normal healthy subjects (N) and in nonulcer dyspepsia (NUD) patients. They were five to six times higher in duodenal ulcer (DU), or more in Zollinger-Ellison patients. Pentagastrin stimulation induced a five- to sixfold rise in N and NUD patients although it did not affect DU patient sialic acid contents. Relationships between sialic acid content and pepsin output in DU indicate that pepsin exerts a variable mucolytic activity depending on disease evolution. In addition to pepsin, duodenogastric reflux exerts a potent mucolytic effect. Therapeutically, highly selective vagotomy without recurrent ulcer markedly reduced mucus erosion. The reduction of mucus erosion by protective drugs has been observed in some cases but in other cases sialic acid measurement did not allow to verify a protective effect. Adherent mucus analysis by high-performance liquid chromatography (HPLC) should allow one to appreciate GP fractions qualitatively. Combination of both methods should allow further determination of the mucus protective role, simultaneously investigating the adherent mucus quality and eroded GPs.