Mechanisms underlying decreased protein and RNA synthesis in the rat spleen following whole-body X-irradiation.

Whole-body exposure of rats to 1000 R X-rays resulted in decreased rates in protein and RNA syntheses in the spleen from the fourth post-irradiation hour. These changes correspond well with impaired ability of nuclei to polymerise RNA, reduction in template efficiency of chromatin, decrease in the activity of RNA polymerase and inhibition in histone phosphorylation. Protection of the spleen by lead shielding during whole-body exposure to X-rays largely eliminated the observed alterations in protein and nucleic acid synthetic machineries. This suggests that the radiation-induced inhibition in protein and RNA syntheses is mainly due to the direct action of radiation on the spleen itself.     

Apoptosis in the supraspinatus tendon with stage II subacromial impingement

The purpose of this study was to investigate the histopathology, including apoptosis, in the supraspinatus tendon with stage II subacromial impingement. Samples from the critical zone of the supraspinatus tendon were obtained from 5 patients with subacromial impingement syndrome and 10 autopsy cases without shoulder diseases as controls. Three-micrometer-thick sections were cut and stained with hematoxylin-eosin (H-E) for routine histologic examination. Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) method and single-stranded deoxyribonucleic acid (ssDNA) assay in which the frequency of the apoptotic cells was expressed by the apoptotic index. Control supraspinatus tendons showed normal morphology, whereas supraspinatus tendons from shoulders with impingement showed significant mucoid degeneration. Correspondingly, few apoptotic cells were observed in control tendons, whereas a large number of apoptotic cells were observed in the degenerative area of tendons from impingement shoulders. The apoptotic indices were significantly higher in the impingement shoulders (ssDNA, 18.84% +/- 1.75%; TUNEL, 24.92% +/- 2.79%) than in the control shoulders (ssDNA, 5.22% +/- 1.30%; TUNEL, 7.01% +/- 1.05%) (P = .04 for ssDNA and P = .017 for TUNEL). Mechanical impingement seems to cause tendon degeneration and apoptosis of the tendon cells in the supraspinatus tendon in stage II impingement.     

Archform in cleft palate--a computerized tomographic classification

This prospective study was conducted in King George's Medical College, Lucknow, India amongst fifty cleft lip and palate cases to study the various arch forms. The maxillary arch form was traced from Computer Tomograph sections of all the cases pre and post-operatively. The various patterns of arch forms as observed from CT tracings exhibiting U & V shaped with sub-types denominated as posteriorly--convergent (c), divergent (d) and parallel (p). This simplified classification can be used in pediatric dentistry practice.     

Comparative behavioral effects of several anticholinergic agents in rats

Summary The behavioral effects of JB 329 (Ditran) were compared with those of several anticholinergic agents in rats.The tertiary nitrogen-containing compounds (i.e. JB 329, JB 336, atropine, scopolamine) caused an increase in their spontaneous motor activity, decrease in food and water intake and an over-all decrease in the response in the various phases of the multiple schedules of reinforcement (i.e. shock avoidance, fixed-ratio water reinforcement, and time-out). The potency of JB 329 was similar to that of scopolamine and greater than that of JB 336. Atropine was 10 or more times less potent than scopolamine.The quaternary analogues of these drugs showed similar, though very slight, and sometimes reverse effects. The site of action of the tertiary compounds thus appears to be central.Supported by a General Research Support grant and a grant No. UI 00472 from the U. S. Public Health Service.     

Increased incidence of cytoplasmic ANCA (cANCA) and other autoantibodies in leprosy patients from western India

The prevalence of various autoantibodies was studied in 75 leprosy patients comprising eight patients with lepromatous leprosy (LL), 36 patients with borderline lepromatous leprosy (BL) and 31 patients with borderline tuberculoid leprosy (BT), along with 100 normal controls. Certain autoantibodies such as anti-nuclear antibodies (ANA), anti-single stranded DNA (anti-ssDNA) and anti-neutrophil cytoplasmic antibodies (ANCA) were raised among leprosy patients. When ANCA specificities to anti-myeloperoxidase (anti-MPO), anti-proteinase3 (anti-PR3) and anti-lactoferrin (anti-LF) were studied, it was found that the patterns of immunofluorescence such as perinuclear (p-ANCA), cytoplasmic (c-ANCA) and atypical (X-ANCA) and specificity by ELISA to anti-MPO, anti-PR3 and anti-LF varied in the LL, BL and BT groups. However, a higher amount of c-ANCA was observed in 62.5% of leprosy cases, while the incidences of p-ANCA and X-ANCA were lower. The LL group showed a higher incidence of autoantibodies as compared with the BL and BT groups, along with a male preponderance for autoantibody development. Some unusual antibody profiles such as 'X'-ANCA were also observed. The study suggests that autoantibody formation could be quite prevalent and also variable in the spectrum of leprosy cases, and there seems to be a serological overlap among leprosy and autoimmune disease, which could have pathogenetic importance in the leprosy patients developing complications.     

An immunohistochemical method that distinguishes free from complexed SNAP-25

Soluble N-ethylmaleimide-sensitive fusion protein (NSF) attachment protein receptor (SNARE) complexes composed of target (t-) SNAREs syntaxin and SNAP-25 and vesicle SNARE synaptobrevin play an essential role in neurosecretion. It is hypothesized that a transient intermediate complex between the t-SNAREs is formed during the assembly of the ternary complex. The existence of the t-SNARE binary complexes in vivo, however, has not been demonstrated. By using an affinity absorption scheme with preformed syntaxin-SNAP-25 complexes, we isolated antibodies capable of distinguishing free SNAP-25 from those associated with syntaxin. By semiquantitative immunohistochemistry, we estimated that, in cultured cerebellar neurons, the majority of SNAP-25 existed as complexes. Compared with the cultured neurons, PC12 cells expressed significantly less syntaxin, and we found that SNAP-25 was primarily in free forms. In contrast, a PC12 line that stably expressed a recombinant syntaxin showed a marked increase in SNAP-25 complexes. By using fluorescence resonance energy transfer (FRET) techniques, we observed FRET between cyan fluorescence protein-syntaxin and yellow fluorescence protein-SNAP-25 fusion proteins expressed in COS-7 and PC12 cells, suggesting a physiological interaction between syntaxin and SNAP-25. Our results demonstrate that, unlike what was previously hypothesized, syntaxin and SNAP-25 exist preferably as stable binary complexes in neurons. These findings offer novel insight into the mechanisms underlying the initiation and regulation of SNARE complex assembly.