The views expressed in this commentary are solely the responsibility of the authors and they do not necessarily reflect the views, decisions, or policies of the institutions with which they are affiliated.

Although the presence of granulomas can support a diagnosis of Crohn disease, severe inflammation and other abnormalities occur in the proximal gastrointestinal tract in Crohn disease and ulcerative colitis.

No abstract

ThedaytimefastingofRamadanisobservedannuallyby millions of adult Muslims all over the world. Some may have mild, moderate or severe medical conditions. They may seek advice on feasibility and safety of fasting and/ ortheirmanagement.Physiciansoughttohaveaworking knowledgeaboutthereligiousrulesofRamadanfastand theirmedicalimplications.Inthisarticlewepresentaconcise summaryoftheproceedingsofaseriesofsymposia.Their objectivesweretoreviewtheeffectsofRamadanfastingon thehealthofMuslimpatientswithvariouschronicmedical conditionsandtoproposepracticalmanagementstrategies. An initial introductory Islamic perspective on fasting to setthesceneforthefollowingpresentations.Thereligious rulingsexcludingpatientswithacuteandchronicmedical conditionsfromfastingwerehighlighted.Therolesofthe medicalprofessionalinguidingpatientsonbestwaystomake

Acid-base status and renal acid excretion were studied in the Dahl/Rapp salt-sensitive (S) rat and its genetically salt-resistant counterpart (R). S rats developed hypertension while on a very high salt diet (8%) and while on a more physiological salt diet (1%) and remained normotensive while on a very low salt diet (0.08%). Under the high salt diet, intracellular pH measured in freshly isolated thymic lymphocytes using 2',7'-bis (carboxyethyl)-5 (6)-carboxyfluorescein acetomethyl ester, a pH-sensitive dye, was lower in S than in R rats both when measured in the presence of HCO3/CO2 (7.32±0.02 vs. 7.38±0.02, respectively, P < 0.05) and in its absence (7.18±0.04 vs. 7.27±0.02, respectively, P < 0.05). Under the high salt diet, net acid excretion was higher in S than R rats (1,777±111 vs. 1,017±73 gEq/24 h per 100 g body wt, respectively, P < 0.001), and this difference was due to higher rates of both titratable acid and ammonium excretion. Directionally similar differences in intracellular pH and net acid excretion between S and R rats were also observed in salt-restricted animals. In S and R rats placed on a normal salt intake (1%) and strictly pair-fed to control food intake as a determinant of dietary acid, net acid excretion was also higher in S than in R rats (562±27 vs. 329±21 ,uEq/24 h per 100 g, respectively, P < 0.01). No significant difference in either blood pH or bicarbonate levels were found between S and R rats on either the 0.08%, 1%, or 8% salt diets. We conclude that renal acid excretion is augmented in the salt-sensitive Dahl/Rapp rat. Enhanced renal acid excretion may be a marker of increased acid production by cells from subjects with salt-sensitive hypertension. (J. Clin. Invest. 1993. 91:2178-2184 Key words: saltsensitive hypertension * acid excretion * intracellular pH -Na+ / H + antiporter * acid base