Effects of new fish oil derivative on fatty acid phospholipid-membrane pattern in a group of Crohn's disease patients

Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods.     

Thyroid function studies in patients with cancer of the larynx: preliminary evaluation

OBJECTIVE: Our goal was to evaluate thyroid function before and after surgery only or radiotherapy plus surgery for laryngeal neoplasms. STUDY DESIGN AND SETTING: The study group consisted of a total of 30 patients with laryngeal cancer (22 treated with surgery only and 8 treated with surgery plus radiotherapy) who were evaluated by ultrasensitive thyroid-stimulating hormone, free T4, and antithyroid antibodies both preoperatively and at 6 and 12 months after surgery. RESULTS: All patients had normal thyroid function before treatment (1 patient had elevated antithyroid autoantibodies); after 1 year, 4 (13.34%) patients were hypothyroid. In 3 patients, it was subclinical (ie, elevated thyroid-stimulating hormone with normal free T4), and in 1 patient, it was symptomatic. CONCLUSION: Our preliminary data suggest that hypothyroidism occurs in a small but substantial proportion of patients undergoing surgery with or without adjuvant radiotherapy for laryngeal cancer. SIGNIFICANCE: Thyroid hormone dosing should be routinely included in the assessment of patients with laryngeal cancer, because it is simple and inexpensive and may allow the early diagnosis and management of hypothyroidism.     

Glutamate-induced calcium signaling in astrocytes

Astrocytes respond to the excitatory neurotransmitter glutamate with dynamic spatio-temporal changes in intracellular calcium [Ca²⁺]_i. Although they share a common wave-like appearance, the different [Ca²⁺]_i changes--an initial spike, sustained elevation, oscillatory intracellular waves, and regenerative intercellular waves--are actually separate and distinct phenomena. These separate components of the astrocytic Ca²⁺ response appear to be generated by two different signal transduction pathways. The metabotropic response evokes an initial spatial Ca²⁺ spike that can propagate rapidly from cell to cell and appears to involve IP₃. The metabotropic response can also produce oscillatory intracellular waves of various amplitudes and frequencies that propagate within cells and are sustained only in the presence of external Ca²⁺. The ionotropic response, however, evokes a sustained elevation in [Ca²⁺]_i associated with receptor-mediated Na⁺ and Ca²⁺ influx, depolarization, and voltage-dependent Ca²⁺ influx. In addition, the ionotropic response can lead to regenerative intercellular waves that propagate smoothly and nondecrementally from cell to cell, possibly involving Na⁺/Ca²⁺ exchange. All these astrocytic [Ca²⁺]_i changes tend to appear wave-like, traveling from region to region as a transient rise in [Ca²⁺]_i. Nevertheless, as our understanding of the cellular events that underlie these [Ca²⁺]_i changes grows, it becomes increasingly clear that glutamate-induced Ca²⁺ signaling is a composite of separate and distinct phenomena, which may be distinguished not based on appearance alone, but rather on their underlying mechanisms. © 1994 Wiley-Liss, Inc.     

Enumeration of S-phase cells in normal rat liver by immunohistochemistry using bromodeoxyuridine-antibromodeoxyuridine system

The visualization of incorporation sites of the thymidine analog bromodeoxyuridine (BrdU) into DNA, detected by immunocytochemistry, has been proposed as an index of the percentage of S-phase cells in a variety of tissues and as an easy, less expensive alternative to autoradiography. This technique has not yet been applied to the study of physiological cell renewal in the normal liver. In the present study, results obtained with this method in the liver of normal young adult rats is reported. BrdU was administered in vivo and subsequent incorporation was detected by the PAP technique using monoclonal anti-BrdU antibodies. The nuclei exhibiting a positive reaction within the liver were few and accounted for about 0.45% of all hepatocytes. Positive cells were located preferentially in zone 1, which contained 82.7% of the labeled cells. Zone 2 contained 15.4%, while only 1.9% of the labeled cells were found in zone 3. Positive-staining Kupffer cell nuclei were rare (about 0.5% of all Kupffer cells) and were distributed randomly in the hepatic lobule. These findings provide quantitative data about hepatocyte renewal in the normal liver in the absence of a growth stimulus. The simplicity and the reproducibility of this technique suggests that further application of this method in situations assessing hepatic regeneration are indicated.     

Pharmacological study of the chicken's monocular optokinetic nystagmus: effects of GABAergic agonist and antagonists.

When injected into the chicken open eye, the GABA-agonist THIP and the GABA-antagonists bicuculline and picrotoxin induced spontaneous eye movements in nasal-temporal (N-T) and in temporal-nasal (T-N) direction, respectively. These spontaneous movements were scarcely modulated by optokinetic stimulation, irrespective of the direction of stimulation. It is suggested that they are due to the suppression of directional selectivity of retinal ganglion cells. When injected into the closed eye, GABAergic drugs did not produce spontaneous nystagmus. THIP provoked a reduction of the N-T component, without modifying the T-N one, while GABA antagonists induced a significant increase in OKN performance, especially for the N-T direction of stimulation. In these conditions, picrotoxin also provoked an increase in the duration of both components of optokinetic after nystagmus, indicating a direct effect of the drug upon the velocity-storage system.