The effect of enteral carnitine administration in humans

Abstract

We previously determined that the L-carnitine uptake by human duodenal tissue occurs by both active (KT 558 mumol/L) and passive mechanisms. The effects of enteral carnitine was studied in humans. A hamburger meal (345 mumol total carnitine) induced peak jejunal fluid free (unesterified) and short-chain acylcarnitine concentrations (SCAC) of 209 and 130 mumol/L, respectively. Plasma carnitine concentrations and the percent renal reabsorption remained unchanged. By contrast, a pharmacologic dose of free carnitine (25,298 mumol) raised peak intraluminal free and SCAC to 20,660 and 4204 mumol/L. Plasma total carnitine concentrations doubled to 93 mumol/L, and the percent renal reabsorption of free and SCAC declined to 76% and 52%, respectively. In triple-lumen perfusions, 200 mumol carnitine/L was absorbed at 484 nmol.min-1.30 cm-1 jejunum, a rate sufficient for prandial but not pharmacologic assimilation. Our findings indicate that absorption of physiologic and pharmacologic amounts of carnitine occurs predominantly by active transport and passive diffusion, respectively.

Phonemic analysis of Turkish monosyllabic word lists used for speech discrimination (word recognition) tests

“…The decoding process of speech in the brain is not only related with the amplitude, but more importantly it is a mixed function of de-coding of various frequencies in the speech sample, and subsequently but almost concurrently re-synthesizing them for "de-coding" of the articulations. [4][5][6][7][8][9][27][28][29] Therefore, most of the patients present hearing problems as the only difficulty in understanding speech. [8] Frequency specific information is coded in the frequency specific regions of the cochlea, and each fiber originating from the frequency specific regions joins into the cochlear nerve in a very particular localization.…”

“…Speech tests are also very useful during the fitting to prove that the device provided enough frequency spectrums for understanding the speech in daily life. [2,[4][5][6][7][8][9][29][30][31] In short, the clinicians need speech tests to show how the subject recognizes the words for better clinical diagnosis.…”

“…[4][5][6][7][8][9] It has been shown that CVC is the major single-word format in Turkish. [32,33] In the literature there is no clear support for such an assumption that a single word format and particularly CVC is better than the others.…”

“…[2,3] Speech has been used as a stimulus for testing hearing of human beings. [4][5][6][7][8][9] As it is known, speech audiology is a way to evaluate hearing quality and quantity in addition to tonal audiometry, and very essential for hearing device fitting. The important part of the linguistic background above for otolaryngologists and audiologists is that speech audiology has been developed via national languages, which should be based on mother tongue.…”

“…The sub-lists should be compatible with the phonemic balance of the standard spoken language and presented to the subjects with true pronunciation with proper suprasegmental features. [4][5][6][7][8][9][10][11][12][13][14] We previously reported that seven studies, including eight Turkish word lists that were developed for speech audiology, were published in Turkish [15][16][17][18][19][20][21][22] (Table 1). [23] The studies presented their clinic efficiency even if some of them have not been in routine use of audiology departments.…”