Mammalian UPF3A and UPF3B can activate nonsense-mediated mRNA decay independently of their exon junction complex binding.

Nonsense-mediated mRNA decay (NMD) is governed by the three conserved factors-UPF1, UPF2, and UPF3. While all three are required for NMD in yeast, UPF3B is dispensable for NMD in mammals, and its paralog UPF3A is suggested to only weakly activate or even repress NMD due to its weaker binding to the exon junction complex (EJC). Here, we characterize the UPF3A/B-dependence of NMD in human cell lines deleted of one or both UPF3 paralogs. We show that in human colorectal cancer HCT116 cells, NMD can operate in a UPF3B-dependent and -independent manner. While UPF3A is almost dispensable for NMD in wild-type cells, it strongly activates NMD in cells lacking UPF3B. Notably, NMD remains partially active in cells lacking both UPF3 paralogs. Complementation studies in these cells show that EJC-binding domain of UPF3 paralogs is dispensable for NMD. Instead, the conserved "mid" domain of UPF3 paralogs is consequential for their NMD activity. Altogether, our results demonstrate that the mammalian UPF3 proteins play a more active role in NMD than simply bridging the EJC and the UPF complex.

Salivary and serum biomarkers of inflammation in a man with metastatic medullary thyroid carcinoma and hyperreactive gingiva: a fourteen year odyssey.

A peripheral (gingival) fibroma, a gingival cyst and hyperplastic gingivitis occurred simultaneously in a man with metastatic medullary thyroid carcinoma (MCT). The gingival growths and hyperplasia appeared to be related to poor oral hygiene rather than to the MTC. Despite the patient's improved oral hygiene, the hyperplastic gingivitis and peripheral fibroma recurred, and a new peripheral fibroma and gingival cyst developed, which prompted reconsideration of a link with the MTC. MTC cells secrete calcitonin (CT), procalcitonin (ProCT) and growth factors; the patient's serum CT and ProCT were several fold higher than normal. The patient's salivary CT and ProCT also were elevated, but α-amylase and epidermal growth factor (EGF) were not, compared to three healthy controls. A possible link between the MTC and gingival hyper-reactivity due to CT and/or ProCT promoting inflammatory cytokines, and the utility of salivary ProCT as an indicator of periodontitis in this patient were explored further. Unstimulated whole saliva and serum were collected from the patient followed by a standard periodontal examination before periodontal treatment, and 3 weeks and 3 months after treatment. This cycle was repeated 7 months after the previous periodontal treatment. The saliva was assayed for ProCT and the serum was assayed for ProCT, high sensitivity C-reactive protein (CRP), interleukin-6 (IL-6) and proadrenomedullin (ProADM). The results were analyzed for correlations among the severity of periodontitis and the biomarkers/cytokines. Only the salivary ProCT was correlated with the severity of periodontitis, i.e. it was higher just before and lower at 3 weeks and 3 months after each periodontal treatment. The patient's salivary ProCT content also was much higher than reported elsewhere. The other biomarkers/cytokines were within normal ranges. Our findings indicate that salivary ProCT is independent of serum ProCT and therefore may be a useful marker for moderate to severe periodontitis in patients with MTC. The greatly elevated salivary and serum CT and ProCT, and a trend toward correlation between the serum CRP and ProCT suggest a pro-inflammatory link between the MTC and the hyperreactive gingiva in this patient. Further studies are warranted to determine whether hyperplastic gingivitis and gingival growths, such as cysts and fibromas, occur with unusual frequency in patients with MTC.

Botryoid odontogenic cyst. Exploration of proliferative activity, apoptosis and expression of TP53 and BCL2 compared to the histologically identical lateral periodontal and gingival cysts.

The botryoid odontogenic cyst (BOC) is a rare, locally more aggressive variant of the usually indolent lateral periodontal cyst (LPC) and gingival cyst (GC). A recent case of BOC provided an opportunity for an exploratory study on the causes of its more aggressive behavior. The limited objective was to see if the BOC was sufficiently different from the other cysts to warrant an investment in a large study. Sections of neutral buffered formalin fixed, paraffin-embedded tissues from the BOC and archival specimens of four GCs, four LPCs and three odontogenic keratocysts (OKCs) were stained using immunohistochemistry for Ki-67, a marker of proliferating cells, caspase-3, a marker of cells undergoing apoptosis, tumor suppressor p53, and the apoptosis inhibitor BCL2. The mean labeling index (LI) of immunoreactive cyst epithelial cells was computed for each antibody and type of cyst. Compared to the LPCs and GCs, the BOC exhibited a moderately larger Ki-67/caspase-3 LI difference, which indicates that the BOC had a net higher rate of growth. We found a much higher level of LI, therefore likely dysregulation of p53. We also found a much higher LI of BCL2. The LIs of p53 and BCL2 in the BOC were similar to and more than twice that of the OKCs, respectively. Although meaningful statistical analysis was precluded by our use of only one case of BOC and a small number of the other cysts, the high p53 and very high BCL2 labeling indices of the BOC offer a potential explanation for its reportedly more aggressive behavior that clearly is worthy of further investigation.

The effect of a new ejection seat headbox and high G garments on head mobility during air combat.

Full coverage anti-G trousers, a chest counter pressure garment for positive pressure breathing for G tolerance, and a smaller ejection seat headbox have been developed for future agile aircraft. The hypotheses that the new headbox might improve, and that the more restrictive high G garments might compromise, pilot head mobility were tested. The RAF institute of Aviation Medicine Hawk aircraft was equipped with a wide angle video camera facing the front seat pilot. Two experimental conditions were compared to the control air combat sortie: 1. standard garments and the smaller headbox; 2. high G garments and the smaller headbox. Data were recorded from five instructor pilots during three scheduled air combat training sorties. Their helmets were marked with 10-mm white dots in a standardized pattern. Software for recording helmet dot positions from single frame video images, and a trigonometric method for calculating head rotation and translation from changes in the helmet dot positions were devised. No differences were found between headboxes or garments at the three extremes of head movements analyzed. Observed neck rotations were similar to maximal seated norms. Optimal head and neck extension is impeded by the ejection seat headbox. Pilots' head movements are not restricted during air combat at moderate G levels.

A kinetic study of sulindac in the elderly.

To study the disposition of the anti-inflammatory drug sulindac, its active sulphide metabolite, and the inactive sulphone metabolite, sulindac (200 mg twice daily) was given to eight elderly subjects for at least 14 consecutive days. The drug was then ceased for 72 hours, and suitable samples were collected to study its elimination. The mean steady-state concentration for sulindac was 5.0 micrograms/ml, for sulindac sulphide was 6.5 micrograms/ml, and for sulindac sulphone was 13.2 micrograms/ml. These are approximately twice the reported steady-state levels for the respective redox forms in healthy young adults. The mean half-lives of sulindac, sulindac sulphide, and sulindac sulphone were 18.3 hours, 22.3 hours, and 54.6 hours, respectively. One patient who had mildly abnormal liver function tests developed more severe abnormalities whilst receiving sulindac. These returned towards normal after cessation of treatment. This patient had the highest steady-state plasma concentration of sulindac sulphone. It is concluded that care should be taken with the use of sulindac in the elderly, and control of patients' symptoms should be attempted with lower doses of the drug before the standard dose of 200 mg twice daily is administered.

Antibiotic-associated colitis caused by Clostridium difficile: relapse and risk factors.

Relapse is a common sequel of antibiotic-associated colitis due to Clostridium difficile. It has been suggested that Cl. difficile may persist in the stools in spite of the resolution of symptoms after treatment and this may cause the relapse. Our study was designed to define the factors that predispose to relapse and to determine if prolonging treatment to clear Cl. difficile from the stools might prevent relapse. Of 60 consecutive patients, 36 with more severe disease required treatment. Treatment with either vancomycin or bacitracin was continued until the results of the examination of stools for cytotoxin became negative and Cl. difficile could no longer be cultured (sensitivity of culture was 10-100 organisms/mL). This was achieved in 35 patients who were then followed for one month. Symptoms reappeared in 10 (28.6%) of the treated patients while Cl. difficile reappeared in the stools of an additional seven patients (20%) without the recurrence of diarrhoea. On comparing those who relapsed with those who did not, the age (67.3 +/- 5.5 years in those who relapsed compared with 51.6 +/- 4.4 years; P less than 0.025, means +/- SE) and a history of recent abdominal surgery (59% of those who relapsed compared with 17%; P less than 0.05) were significantly different. Although those who relapsed had received therapy with multiple antibiotic agents more often, this was not statistically significant. Disease was not more severe in patients who relapsed, nor was it more difficult to clear the pathogen from these patients. The 24 untreated patients did not suffer symptomatic relapse. Continuation of treatment until Cl. difficile apparently is absent from the stools is expensive and does not prevent relapse. Elderly patients and those who have recently undergone abdominal surgery are more likely to suffer a relapse.

Antibiotic-associated colitis due to Clostridium difficile: double-blind comparison of vancomycin with bacitracin.

A randomized double-blind study was carried out in patients with unresolving antibiotic-associated colitis due to Clostridium difficile, to compare the effect of bacitracin (80,000 U/day) with vancomycin (500 mg/day) on the resolution of symptoms, clearance of organism, and prevention of relapse. Forty-two patients with colitis, 9 of whom had a pseudomembrane, were randomized, 21 patients to each treatment group. The two groups were comparable in age, disease severity, and antibiotic exposure. For a 50% reduction in stool frequency the mean times (+/- SE) were 4.1 +/- 0.4 days for bacitracin and 4.2 +/- 0.4 days for vancomycin. Sixteen patients (76%) had symptom resolution after 7 days of treatment with bacitracin, compared with 18 patients (86%) given vancomycin. Patients who failed to respond were crossed over (blind) to the alternative antibiotic, but tended to be refractory to the alternative medication as well. Vancomycin-treated patients had negative toxin (83% vs. 53%, p = 0.04) and negative stool cultures (81% vs. 52%, p = 0.02) more frequently than did those patients given bacitracin. Similar numbers of patients in each group had symptomatic relapse during 1 mo of follow-up, but most of them relapsed yet again after blinded crossover therapy. Although bacitracin was significantly less effective than vancomycin in clearing C. difficile from the stools, both were of similar value in the control of symptoms in a group of patients with predominantly nonpseudomembranous colitis. In view of its low cost, bacitracin is a reasonable first-line alternative to vancomycin in the treatment of antibiotic-associated colitis.

Subendocardial myocardial infarction.

Sixty-one consecutive patients with acute subendocardial myocardial infarction (SEAMI) and 223 consecutive patients with transmural infarction (TMI) seen in a coronary care unit were followed for one year. All patients were less than 70 years of age. The patients with SEAMI had a higher frequency of previous infarction (34% vs 21%, p less than 0.025), less cardiac failure (44% vs 65%, p less than 0.005), and were more often free from arrhythmias (61% vs 31%, p less than 0.001) than patients with TMI. Hospital mortality was less in patients with SEAMI (0% vs 8%, p less than 0.05) but total mortality to one year was similar (15% vs 17%). Amongst patients with SEAMI, two died within two weeks of infarction but all other deaths occurred at least six weeks after infarction. Patients with SEAMI and a history of previous infarction had a higher one year mortality than patients without such a history (29% vs 7%, p less than 0.05). Coronary angiography with a view to coronary artery surgery should be considered in the former group.

Infant vocalizations and their relationship to mature intelligence.

Correlations between infant development tests and later intelligence have been found previously to be very low. Through cluster analysis, six clusters of items were extracted from Bayley's California First Year Mental Scale. One item cluster composed principally of vocalizations did significantly correlate with girls' later intelligence, increasingly so with age, and more highly with verbal than performance scores.