Effects of bursectomy and thymectomy on the development of resistance to Cryptosporidium baileyi in chickens

 Comparisons were made between the course of infection with Cryptosporidium baileyi in normal chickens and in chickens with functional deficiencies in either B-lymphocytes (bursectomized) or T-lymphocytes (thymectomized). Bursectomy did not influence the acquired immune response to C. baileyi infection as measured by the oocyst excretion. However, the total oocyst output of bursectomized birds was less than a quarter of that of the controls due to the reduced site for multiplication of the parasite. The total oocyst output of thymectomized chickens was more than 2 times higher and the patency was 2 times longer as compared with control animals. Moreover, thymectomized birds failed to acquire resistance to the challenge infection. These findings attest to the primary role of cell-mediated immunity in the expression of resistance to C. baileyi as opposed to the antibody-mediated mechanisms. Received: 24 March 1995 / Accepted: 16 June 1995     

Method for isolation of kappa-opioid binding sites by dynorphin affinity chromatography

A kappa-opioid receptor subtype was purified from a digitonin extract of frog brain membranes, using affinity chromatography. The affinity resin was prepared by coupling dynorphin (1-10) to AH Sepharose 4B. The purified receptor binds 4,750 pmol [3H]ethylketocyclazocine (EKC) per mg protein (5,600-fold purification over the membrane-bound receptor) with a Kd of 9.1 nM. The addition of cholesterol-phosphatidylethanolamine (2:1) enhanced 3.6-fold the binding activity of the purified material, which gives a purification very close to the theoretical. The purified receptor protein exhibits high affinity for kappa-selective ligands. The purified fraction shows one major band (65,000 Mr) in sodium dodecyl sulfate (SDS) gel electrophoresis.     

Eosinophilic fasciitis is clinically distinguishable from the eosinophilia-myalgia syndrome and is not associated with L-tryptophan use

Induration of the skin develops in a majority of patients with the eosinophilia-myalgia syndrome associated with L-tryptophan, and bears striking clinical and histopathological resemblance to eosinophilic fasciitis (EF). These similarities have led to the suggestion that eosinophilia-myalgia syndrome and EF are the same disease. To study the relationship of eosinophilia-myalgia syndrome and EF, we ascertained the prevalence of L-tryptophan use in a cohort of patients with EF, and compared their clinical and laboratory findings to those of patients with eosinophilia-myalgia syndrome associated cutaneous involvement. None of 11 patients who were diagnosed as having EF between 1970 and 1989 used L-tryptophan containing preparations prior to the onset of their illness. Marked clinical and laboratory test differences were observed between patients with EF and eosinophilia-myalgia syndrome. Patients with eosinophilia-myalgia syndrome had a more acute onset, more severe symptoms, higher frequency of rash and of pulmonary, cardiac, gastrointestinal, neurologic, myopathic and thyroid involvement compared to patients with EF. Corticosteroid therapy resulted in improvement of cutaneous involvement in 88% of patients with EF but it was only partially successful in patients with eosinophilia-myalgia syndrome. Hospitalization and fatalities occurred only among patients with eosinophilia-myalgia syndrome. These observations demonstrate that eosinophilia-myalgia syndrome is a more severe disease with multisystemic involvement that can be clinically distinguished from EF. In contrast to eosinophilia-myalgia syndrome, EF is not associated with L-tryptophan ingestion.     

Effects of estrone on the biliary excretion of xenobiotics

The effect on the biliary excretion of exogenous organic anions and the mechanism of action of estrone has been studied. Female Wistar rats weighing 180-200 g were pretreated with estrone (2.5 mg/kg ip daily for 4 days). This produced a significant decrease in the biliary flow and biliary excretion of bromcresol green and amaranth. Administration of taurocholate did not abolish the depressing effect of estrone; however, phenobarbital given in combination with estrone decreased or prevented the effects of estrone on the biliary excretion rate of bromcresol green and amaranth. These results indicate that changes in the bile salt independent fraction might be responsible for the effects of estrone on the biliary flow and biliary excretion of xenobiotics.     

Cerebral Effects of a Single Dose of Intravenous Vinpocetine in Chronic Stroke Patients: A PET Study

The effects of vinpocetine (Cavinton) on the cerebral glucose metabolism of chronic stroke patients are studied with positron emission tomography. The regional and global cerebral metabolic rates of glucose (C MR91 u) and the kinetic constants related to them are quantified before and after single-dose intravenous vinpocetine treatment. These measurements are completed with transcranial Doppler sonography and single photon emission computed tomography to explore the possible mechanisms underlying the resulting changes in glucose uptake and metabolism in the brain. The authors' findings indicate that a singledose vinpocetine treatment, although it does not affect significantly the regional or global metabolic rates of glucose, improves significantly the transport of glucose (both uptake and release) through the blood-brain barrier in the whole brain, the entire contralateral hemisphere, and in the brain tissue around the infarct area of the symptomatic hemisphere. These changes are in accord with increased blood flow in the entire contralateral hemisphere as well as decreased blood flow velocity and increased peripheral vessel resistance in the entire symptomatic hemisphere.     

Biochemical bases of the antifertility action of the nonsteroidal antiandrogen niphtolid

The study was made of biosynthesis and levels of nucleic acids and proteins in the head of epididymis as well as of the fertility of intact mature male rats under antiandrogenic exposure to nonsteroid antiandrogenic compound niphtolid. Niphtolid given per os in a dose of 25 micrograms/kg during 8 or 30 days decreased the mass of the organ and its concentrations of DNA, RNA and proteins. The above mentioned alterations seemed to be caused by inhibited inclusion of labeled precursors into biopolymers. A long-term intake of antiandrogen (10 micrograms/kg of body mass daily for a six-months period) was followed by developing transient infertility. The possibility to use niphtolid-like compounds both alone and in combination with antigonadotrophic drugs for fertility regulation is assumed.     

Cell surface markers, inositol phosphate levels and membrane potential of lymphocytes from young and old human patients

It is well known that most physiological functions change with aging, including the immune response. Data concerning the aging of lymphocyte subpopulations are conflicting. The antigen density of peripheral blood lymphocytes has been determined by fluorescently tagged OKT-3, OKT-4, OKT-8, OKT-11 and OKM1 monoclonal antibodies in a carefully selected aged (over 87 years) population, and compared to that of young subjects. A substantial difference was found in the percentage distribution of OKT8 and OKM1 subsets. The volume of lymphocytes of the elderly population was significantly less than that of the young. The effect of various monoclonal antibodies on phosphatidylinositol breakdown has also been studied. It was found that only OKT3, acting through the CD3 antigen receptor, was able to induce inositol phosphate formation in both young and elderly, although in the latter population this occurred at a lower level. Because the plasma membrane plays a regulatory role in this process, an important and sensitive functional parameter, the membrane potential, was also monitored and influenced by changing the extracellular K+ concentration. The lymphocytes of the elderly population responded less sensitively to changes in extracellular potassium concentration.     

Preferential localisation of red cell vacuoles to pathologically shaped human red blood cells

The percentage of pitted erythrocytes and Howell-Jolly bodies in peripheral blood samples of 51 individuals following posttraumatic splenectomy and 20 patients splenectomized because of various haematological diseases differed significantly from each other (p less than 0.001) and from that of healthy controls (p less than 0.001). The percentage of pitted erythrocytes was significantly higher in pathologically shaped red blood cells (RBCs) (acanthocytes, schizocytes, elliptocytes) than in normal discoid shaped RBCs (p less than 0.001). As the number of pits per RBC showed great individual variations, a scoring system for the evaluation of pitted RBCs is proposed.