Superoxide production by broncho-alveolar cells is diminished in parainfluenza-3 virus treated guinea pigs

Guinea pig airways isolated 4, 8 and 16 days (but not 2 days) after intra-tracheal inoculation with parainfluenza-3 virus In Vivo respond hyperreactive to contractile stimuli. In the present study it is shown that the virus-induced airway hyperresponsiveness is associated with a decreased Superoxide production by broncho-alveolar cells after additional stimulation with parainfluenza-3 virus.

Upper gastrointestinal manifestations in rheumatoid arthritis patients: intrinsic or extrinsic pathogenesis?

Apart from the complication of gastrointestinal vasculitis it is not known whether the upper gastrointestinal (UGI) tract has any special disease characteristics in rheumatoid arthritis (RA). However, oesophageal motility disorders have been reported in 30% of RA patients. Hypergastrinaemia has been found in 23-43% of RA patients, usually in combination with a decreased gastric acid output. Another finding suggestive of a decreased secretory state, namely a decreased level of pepsinogen A, was found in RA patients with the sicca syndrome and in patients with active disease. The risk for peptic ulcer disease with regard to nonsteroidal anti-inflammatory drugs (NSAID) is possibly higher in RA patients than in patients with other rheumatic diseases. These findings suggest that in RA patients intrinsic factors play a role in the pathogenesis of the oesophageal motility disorders, in hypergastrinaemia and hypopepsinogenaemia and the related decreased gastric secretory state, and possibly in the increased susceptibility to NSAID-related ulcers. However, there are also indications that oesophageal motility disorders, hypergastrinaemia, and NSAID-related ulcers in RA are the result of extrinsic factors, mainly the use of NSAIDs. The effects of NSAIDs and gold compounds on infection with Helicobacter pylori, a possible pathogenetic factor in ulcer disease, is discussed. It is clear that the discussion about intrinsic and extrinsic factors as a cause of the UGI manifestations in RA remains an intriguing but difficult subject for further studies.

Campylobacter species identification based on polymorphism of DNA encoding rRNA

Total DNA from five Campylobacter species was digested with a mixture of XhoI and BglII restriction endonucleases and analyzed by Southern hybridization by using a probe complementary to the DNA coding for the 16S rRNA. Each of the Campylobacter species, including C. jejuni, C. coli, C. laridis, C. fetus, and C. upsaliensis, displayed a characteristic pattern. Although some bands may be common to different species, the simplicity of the hybridization pattern enabled us to discriminate among the different species of Campylobacter.

Radiofrequency ablation of ventricular myocardium using active fixation and passive contact catheter delivery systems

This study examined the qualitative and quantitative effects of radiofrequency energy using active fixation and passive contact catheter delivery systems on normal bovine atrium and ventricle and diseased human ventricle in vitro. Two active fixation (custom screw-in or suction electrode) catheters and two passive contact (custom ring or standard electrode) catheters were used with a 500 kHz radiofrequency current generator. Linear regression analysis between lesion dimensions and power output showed excellent correlation coefficients for all catheter delivery systems except the suction catheter. Lesion sizes also increased with duration of radiofrequency energy delivery at low power using the USCI quadripolar catheter. Lesion size in diseased human ventricle was considerably smaller than in the normal ventricle. Comparison of induced lesion dimensions using pulsed and continuous delivery modes showed only minor differences. Tissue impedance was relatively constant during energy delivery. Arcing was associated with a sudden increase in voltage and impedance and a sudden decline in current. This was most frequently observed at high power and with the suction electrode catheter. The use of high (50 W) power output and prolonged application (up to 180 seconds) in atrium and ventricle did not induce perforation. We conclude that a variety of catheter delivery systems can be used for effective radiofrequency energy delivery and ablation in atrial and ventricular myocardium in the pulsed or continuous mode. Impedance changes during radiofrequency ablation cannot be used to guide the extent of ablation but do detect arcing during the procedure.

Active uptake and extravesicular storage of m-iodobenzylguanidine in human neuroblastoma SK-N-SH cells

Radio-iodinated m-iodobenzylguanidine (MIBG), an analogue of the neurotransmitter norepinephrine (NE), is increasingly used in the diagnosis and treatment of neural crest tumors. Active uptake and subsequent retention of MIBG and NE was studied in human neuroblastoma SK-N-SH cells. Neuron-specific uptake of [125I]MIBG and [3H]NE saturated at extracellular concentration of 10(-6) M and exceeded by 20-30-fold that by passive diffusion alone. A minimum of 50% of accumulated MIBG remained permanently stored but the SK-N-SH cells were incapable of retaining recaptured [3H]NE. [125I]MIBG was displaced from intracellular binding sites by unlabeled MIBG with 10-fold higher potency than by unlabeled NE. MIBG stored in SK-N-SH cells was insensitive to depletion by the inhibitor of granular uptake reserpine (RSP) and was not precipitated in a granular fraction by differential centrifugation. Only few electron-dense granules were found in these cells by electron microscopy. In contrast, MIBG storage in PC-12 pheochromocytoma cells which contained many storage granules, was sensitive to RSP and part of accumulated drug was recovered in a granular fraction. Accordingly, storage of MIBG in the SK-N-SH neuroblastoma cells is predominantly extravesicular and thus essentially different from that of biogenic amines in normal adrenomedullary tissue or in pheochromocytoma tumors, while sharing with these tissues a common mechanism of active uptake.

Insulin-like growth factor-1 receptors and insulin-like growth factor-1-like activity in human primary breast cancer

In the current study the authors have investigated whether human primary breast cancer specimens contain insulin-like growth factor-1 (IGF-1) receptors (IGF-1-R) or IGF-1-like activities. Simultaneously, epidermal growth factor (EGF) receptors (EGF-R) and cytosolic estrogen receptor (ER), progesterone receptor (PR), and EGF-like activity were determined. All tumors assayed contained a single class of specific iodine 125 (125I)-IGF-1 binding sites (Kd: median 106, range 48-755 pM; n = 32) with limited capacity (Bmax: median 147, range 19-11,900 fmol/mg membrane protein). Seventy percent of 44 tumors (50% ER+, PR+), displayed specific 125I-EGF binding with a wide range of values (median 13, range 2-215 fmol/mg protein, n = 31). A positive relationship was apparent between the amount of IGF-1-R with ER and PR (Spearman; 2P less than 0.02 and 2P less than 0.01, respectively; n = 32), whereas for EGF-R a negative relationship was observed (for both 2P less than 0.01; n = 44). All tumors contained endogeneous IGF-1-like and EGF-like activities as measured by radioreceptor assay on acid-ethanol extracted cytosols (median 15, range 3-131 ng/mg protein, n = 78 for IGF-1; and median 86, range 26-517 ng/mg protein, n = 142 for EGF). Tumor contents of IGF-1-like and EGF-like activities showed a negative relationship with ER (2P less than 0.1 for IGF-1, n = 78; and 2P less than 0.001 for EGF, n = 142), and with PR (2P less than 0.05, n = 78; and 2P less than 0.001, n = 142). No relationship was observed between the tumor contents of IGF-1-like and EGF-like activities. In conclusion, these data support the view that IGF-1 and EGF can act as autocrine or paracrine growth factors in human breast cancer.

Haptic identification of rotated letters using the left or right hand

The present study investigated the effects of the use of the left and right hands on haptic identification of letters which were presented in either a normal (0 degrees rotation), downward (90 degrees clockwise rotation), upside down (180 degrees rotation), or facing upward (270 degrees rotation) position. Each of the 80 right-handed subjects was given five series of randomly ordered presentations of sets of 8 letters of the alphabet. The subjects were asked to feel and then name each letter correctly as quickly but as accurately as possible. Times showed no effect of hand, but significant effects were found for different sets of letters, degree of rotation and a significant decrease in identification time was observed across the five series. Interactions occurred between hand and rotation as well as set and rotation. Errors showed a significant interaction of hand with degree of rotation; the right was superior at 0 degrees but the left was superior at 90 degrees. The results were discussed in terms of hypotheses of hemisphere function, mental rotation, and stimulus familiarity.

New antihistaminic N-heterocyclic 4-piperidinamines. 2. Synthesis and antihistaminic activity of 1-[(4-fluorophenyl)methyl]-N-(4-piperidinyl)-1H-benzimidazol-2-a mines

The synthesis of a series of 1-[(4-fluorophenyl)methyl]-N-(4-piperidinyl)-1H-benzimidazol-2-ami nes and the preliminary evaluation of their in vivo antihistamine activity are described. The title compounds were obtained starting from either 1, 4, 10, or 55 by different synthetic methods. Substitution on the phenyl nucleus of the benzimidazole ring (84-87) was achieved by two different approaches. The in vivo antihistamine activity was evaluated by the compound 48/80 induced lethality test in rats and the antihistamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. The duration of action was studied in the guinea pig for three compounds (4, 51, and 55). Compound 51, "astemizole", was also studied in histamine- and serotonin-induced cutaneous reaction and for mydriatic activity in the rat and tested for peripheral and central effects not related to histamine antagonism in a variety of systems. Astemizole has been selected for clinical investigation.

New antihistaminic N-heterocyclic 4-piperidinamines. 3. Synthesis and antihistaminic activity of N-(4-piperidinyl)-3H-imidazo[4,5-b]pyridin-2-amines

To study the bioisosteric replacement of a 2-pyridyl ring for a phenyl nucleus in astemizole, a series of N-(4-piperidinyl)-3H-imidazo[4,5-b]pyridin-2-amines was synthesized and evaluated. The title compounds were obtained starting from either 8a or 8b by four synthetic methods. The in vivo antihistamine activity was evaluated by the compound 48/80-induced lethality test in rats and the histamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. Compound 37, the isostere of astemizole, showed the most potent antihistaminic properties in the rat. However, astemizole is superior to 37 as to duration of action and total potency.

New antihistaminic N-heterocyclic 4-piperidinamines. 1. Synthesis and antihistaminic activity of N-(4-piperidinyl)-1H-benzimidazol-2-amines

The synthesis of a series N-(4-piperidinyl)-1H-benzimidazol-2-amines and the preliminary evaluation of their in vitro and in vivo antihistaminic activity are described. Cyclodesulfurization of (2-aminophenyl)thioureas with mercury(II) oxide resulted in 2-aminobenzimidazole intermediates, which were monoalkylated on the endo-nitrogen atom. After deprotection of the piperidine nitrogen atom with 48% aqueous hydrobromic acid solution, the title compounds were obtained by three different methods, viz. alkylation, reductive amination, or oxirane ring-opening reactions. The in vivo antihistaminic activity was evaluated by the compound 48/80 induced lethality test in rats and histamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. The duration of action, for a selected number of compounds, was studied in the guinea pig. The phenylethyl derivatives showed the most potent antihistamine properties after oral administration in both animal species.

Anaplastic seminoma of the testis: ultrastructural analysis of three cases

Three anaplastic seminomas of the testis were examined by transmission electron microscopy, and the ultrastructural features are described for comparison with those reported in other seminomas and related neoplasms. It is concluded that anaplastic seminomas are similar ultrastructurally to classic testicular seminomas, extragondal seminomas, and ovarian dysgerminomas, all of which are less differentiated than spermatocytic seminomas.