Crevicular fluid enzymes from endosseous dental implants and natural teeth

Several neutrophil-derived enzymes that are present in the gingival crevicular fluid have been evaluated for use as risk markers for periodontal disease progression. However, very little information is available about the presence of these enzymes in peri-implant tissues. The purpose of this cross-sectional study was to compare levels of enzymes in gingival crevicular fluid between natural teeth and endosseous dental implants and between well-integrated and failing implants. Scores of plaque and gingivitis were recorded for 68 integrated implants, five failing implants, and 34 natural teeth in 12 completely edentulous and 18 partially edentulous subjects. Samples of gingival crevicular fluid were obtained from these sites using filter paper strips and were assayed for levels of neutral protease, neutrophil elastase, myeloperoxidase, and beta-glucuronidase. Neutral protease levels were higher (P = .066) at moderately to severely inflamed implant sites (Gingival Index of 2, 3) compared to mildly or noninflamed sites (Gingival Index of = 0, 1). Despite the small number (n = 5) of failing implants evaluated in this study, levels of neutrophil elastase, myeloperoxidase, and beta-glucuronidase were significantly higher (P < or = .001) around failing implants compared to successful implants. Neutral protease levels were also elevated around failing implants, but the difference was not statistically significant. Results of this study indicate that neutrophil elastase, myeloperoxidase, and beta-glucuronidase levels in GCF appear to be good candidates for study as risk markers of implant failure.     

The synthetic [Tyr5,12,Lys7]-polyphemusin II peptide (T22) binds to the CD4 cell surface molecule

The [Tyr5,12,Lys7]-polyphemusin II peptide (T22) inhibits HIV-1 replication in lymphocytes. The mechanism of T22 inhibition of HIV-1 replication may involve T22 competition with HIV-1 for attachment sites on the plasma membrane of targeted cells. Here we find that the T22 peptide binds to the CD4 molecule in affinity columns. We also find that antiserum to CD4 inhibits cell attachment to T22. Further CD4+ transfected cells attach to T22 while their parental cells which do not express CD4 do not attach to T22. These data demonstrate that T22 binds to the CD4 molecule and supports the hypothesis that T22 inhibits HIV-1 replication by binding to the cell surface CD4 molecule and inhibiting uptake of the virus.     

Axial strain measurements in skeletal muscle at various strain rates

A noncontact optical system using high speed image analysis to measure local tissue deformations and axial strains along skeletal muscle is described. The spatial resolution of the system was 20 pixels/cm and the accuracy was +/- 0.125 mm. In order to minimize the error associated with discrete data used to characterize a continuous strain field, the displacement data were fitted with a third order polynomial and the fitted data differentiated to measure surface strains using a Lagrangian finite strain formulation. The distribution of axial strain along the muscle-tendon unit was nonuniform and rate dependent. Despite a variation in local strain distribution with strain rate, the maximum axial strain, Exx = 0.614 +/- 0.045 mm/mm, was rate insensitive and occurred at the failure site for all tests. The frequency response of the video system (1000 Hz) and the measurement of a continuous strain field along the entire length of the structure improve upon previous noncontact optical systems for measurement of surface strains in soft tissues.     

Differential diagnosis of a mass in the upper lateral neck

The differential diagnosis and the duration of symptoms are presented for a group of 288 patients encountered over a ten-year period with a mass in the region of the neck behind and below the angle of the mandible. While infections constituted the largest aetiological group (48.3 per cent), 109 cases (37.9 per cent) had some form of neoplasia, with malignancy being found in 48 (16.6 per cent). The duration of symptoms varied widely, only the acute infections having an acceptably short delay prior to hospital admission. The mean symptom duration for all the neoplastic cases was in excess of five months.     

Lactic acid production from molasses by Sporolactobacillus cellulosolvens

Sporolactobacillus cellulosolvens (NCIMB 12173) isolated from an anaerobic digester and characterised biochemically is being reported for homofermentative lactic acid production from molasses in a batch culture. The effect of various process parameters on lactic acid production were optimized. A maximum lactic acid (24.2 g/l) and yield coefficient (0.79) was achieved using 3% (v/v) inoculum of 36 h old culture in molasses medium containing sugars (5%; w/v) supplemented with peptone (2.5 g/l) and (NH4)2SO4 (7.5 g/l), pH 6.5 at 40 degrees C after 72 h of fermentation.     

Gene expression of pituitary adenylate cyclase activating polypeptide (PACAP) in the rat hypothalamus

Pituitary adenylate cyclase activating polypeptide (PACAP) isolated from ovine hypothalamus is considered to be a member of the vasoactive intestinal peptide/glucagon/secretin/growth hormone-releasing hormone family of peptides. Two forms of PACAP, PACAP38 and PACAP27, have been demonstrated in the rat hypothalamus. The PACAP precursor contains another peptide called PACAP-related peptide (PRP), but so far no information on this peptide in tissue exists. We have developed three radioimmunoassays specific for PACAP38, PACAP27 and PRP and demonstrate that all three preproPACAP peptides are expressed in the rat hypothalamus, the PACAP38/PACAP27 ratio being around 60 and the PACAP38/PRP ratio being around 10. HPLC analysis of hypothalamic extract showed that PACAP38 and PACAP27 are found in only one form corresponding to the respective synthetic peptides, whereas PRP eluted in two peaks, the predominant form corresponding to synthetic PRP1-29. The cellular distribution of PACAP38, PACAP27, and PRP and corresponding mRNA in the hypothalamus was determined with immunohistochemistry and in situ hybridization histochemistry. PACAP- and PRP-immunoreactive neuronal perikarya were observed in the medial parvocellular part of the paraventricular nucleus (PVN) in colchicine pretreated rats. Some cell bodies of magnocellular variety were found in the PVN. PACAP mRNA containing cells were observed in moderate numbers in the same parts of the paraventricular nucleus. PACAP- and PRP immunoreactive fibres and varicosities were distributed in the PVN and in the periventricular nucleus. These data show that PACAP38, PACAP27 and PRP are expressed in the parvocellular part of the PVN, implying roles as hypothalamic regulatory peptides.     

Arousal, numbing, and intrusion: symptom structure of PTSD following assault

OBJECTIVE: This study investigated hypotheses concerning the importance of symptoms of numbing in posttraumatic stress disorder (PTSD). METHODS: Symptoms of PTSD were assessed in 72 female rape victims and 86 female victims of nonsexual assault approximately 3 months after the crimes occurred. A principal-components factor analysis of subjects' symptoms was then undertaken. RESULTS: The analysis yielded three factors: arousal/avoidance, numbing, and intrusion. These were somewhat different from the symptom clusters in DSM-III-R, since effortful avoidance and numbing symptoms did not load on the same factor. Numbing symptoms appeared to be particularly important in identifying individuals with PTSD. CONCLUSIONS: The results imply that there are two patterns of posttrauma symptoms, one characterizing PTSD and the second characterizing a phobic reaction.