Tobacco smoking: a major risk factor for loss of teeth in three 70-year-old cohorts

Oral health was examined in a random sample of 1377 people in three 70-year-old cohorts studied within 5-yr intervals. During the studied period 1971-1983 the prevalence of toothlessness decreased from 52 to 34%. Toothlessness in men was more common in smokers, 48%, and ex-smokers, 32%, than in non-smokers, 20%. Eichner's index was used as a measurement of dental invalidity. This index showed a worse dental state among smokers and ex-smokers compared to non-smokers. Multivariate analyses indicated that tobacco smoking was a major independent risk factor for tooth loss in elderly men.     

Curriculum factors influencing knowledge of communication skills among medical students

Background  

Communication training builds on the assumption that understanding of the concepts related to professional communication facilitates the training. We know little about whether students' knowledge of clinical communication skills is affected by their attendance of communication training courses, or to what degree other elements of the clinical training or curriculum design also play a role. The aim of this study was to determine which elements of the curriculum influence acquisition of knowledge regarding clinical communication skills by medical students.     

Fusobacterium pneumonia and death following uvulo-palato-pharyngoplasty

A case with a fatal outcome caused by infection with Fusobacterium species was seen in a patient recently operated on for heavy snoring with uvulo-palato-pharyngoplasty (UPPP). The mechanism of infection is discussed. It is concluded that a febrile episode seen in patients less than 2 weeks postoperatively should be considered a serious symptom and be treated intensively after thorough examination. © 1994 John Wiley & Sons, Inc.     

Association between vertical development of the cervical spine and the face in subjects with varying vertical facial patterns.

The upper cervical spine and face were compared longitudinally from 6 to 15 years of age in 2 groups of children with low (n = 16) and high (n = 14) MP-SN angles. The purpose of the study was to assess morphological and incremental associations between the vertical development of the cervical spine and the face in subjects with varying vertical facial patterns. Morphological associations were not detected during the observation period. Long faces were found on children with short necks, and short, square faces on those with long necks. Vertical growth of the upper cervical spine and face were weakly correlated in the 6-to-12-year period but strongly correlated later during puberty. The vertical distance between gonion and the body of the second cervical vertebra was remarkable for its constancy during childhood and puberty, indicating that gonion and the second cervical vertebra body were anatomically interrelated. This anatomical relationship strongly suggests that a mutual relationship also exists between vertical growth of the upper cervical spine and the face, especially the lower face. In addition, the lower face had the ability for independent vertical growth that was not coordinated with vertical cervical growth. This was the case in the 6-to-12-year period, but not later.     

Identification and characterization of clonal NK-like cells from channel catfish (Ictalurus punctatus)

TcR alpha, beta, and gamma chain negative cytotoxic NK-like cells were cloned from alloantigen-stimulated PBL obtained from nai;ve channel catfish. Stimulation with allogeneic cells and growth promoting factors are required for their continued in vitro proliferation and cytotoxic activity. These granular cells kill not only the stimulating allogeneic cells, but also unrelated allogeneic targets by a perforin/granzyme-mediated apoptosis pathway. In addition, they are negative for markers that define neutrophils, monocytes/macrophages, and non-specific cytotoxic cells. Although these NK-like clones kill a number of different allogeneic targets, they display interclonal variation in cytotoxicity toward a panel of allogeneic targets, i.e. some clones have no apparent target specificity, while others display a target preference. In addition, flow cytometric analyses revealed that expression of a putative FcmuR, an LFA-1-like molecule, and a putative thymocyte/T cell antigen varies among the different clones, with no clear correlation between surface antigen expression and cytotoxic activity. Although not all clones express a putative FcmuR, it was noted that they all expressed an ITAM containing FcepsilonR gamma chain homolog. This finding suggests that the catfish FcepsilonR gamma chain may potentially be used as an accessory molecule for not only FcmuRs, but also for other unknown activation receptors. These results support the hypothesis that catfish NK-like cells are heterogeneous in terms of target specificities and cell surface phenotype.     

In vitro behavior of sintered powder injection molded Ti-6Al-4V/HA

This article reports the morphology and mechanical properties of sintered powder injection molded Ti-6Al-4V/HA parts in a simulated physiological environment. Sintered Ti-6Al-4V/HA parts were immersed in a simulated body fluid (SBF) with ion concentrations that were comparable to those of human blood plasma for a total period of 12 weeks. At intervals of 2 weeks, the immersed Ti-6Al-4V/HA parts were analyzed with the use of scanning electron microscopy (SEM), X-ray diffractometry (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Mechanical properties such as flexural strength, flexural modulus, compressive strength, and compressive modulus were also evaluated. Results showed that complete dissolution of the more soluble phases such as tricalcium phosphate (TCP), tetracalcium phosphate (TTCP), and calcium oxide (CaO) were found after 2 weeks of immersion in SBF. ICP analysis showed that high calcium concentration release of around 200 ppm was observed in the SBF solution after 2-4 weeks of immersion, indicating that dissolution has taken place. Next, a gradual decrease in calcium concentration release in the SBF solution was observed after immersion for 4-6 weeks, with increasing amounts of calcium phosphate precipitates being observed on the Ti-6Al-4V/HA surface. Mechanical properties such as strength and modulus were found to deteriorate during 2-4 weeks of immersion, followed by gradual increment as the immersion period increased. This study also showed that parts sintered at 1150 C exhibited faster dissolution and precipitation rates than parts sintered at 1050 C in a physiological environment.     

Processing of HA-coated Ti-6Al-4V by a ceramic slurry approach: an in vitro study

Hydroxyapatite-coated titanium alloy composite powders (Ti-6Al-4V/HA) was produced by a ceramic slurry approach. The aim was to evaluate the stability of the coating when subjected to a physiological medium simulated body fluid (SBF). Three consolidation conditions (700 degrees C for 5 h, 700 degrees C for 8 h and 700 degrees C for 11 h) were used in the production of the Ti-6Al-4V/HA composite powders. Results showed that biodissolution followed by apatite precipitation had taken place after soaking in SBF. In addition, it was found that consolidation at 700 degrees C for 5 h resulted in a weak mechanical locking of calcium phosphate on the Ti-6Al-4V surfaces; and the formation of small crystallites, which would increase the dissolution rate.     

Absence of restricted diffusion in adipose tissue capillaries.

Capillary permeability in adipose tissue for 57Co-cyanocobalamin (57Co-B12) was determined by the single injection, external registration method. The capillary diffusion capacity, CDC, (the permeability-surface area product, PS) was 1.1 ml/100 g-min at a capillary extraction of 0.21 and a plasma flow of 6.7 ml/100 g-min. Results were compared to 51Cr-EDTA data from a previous study with similar method and preparation. As CDC(51Cr-EDTA)/CDC(57Co-B12) was 1.81 and as D(51Cr-EDTA)/D(57Co-B12), the ratio between the free diffusion coefficients in water at 37 degrees C, was 1.79, it is concluded that restricted diffusion does not occur in cutaneous tissue for 57Co-B12 as compared to 51Cr-EDTA, i.e., 51Cr-EDTA and 57Co-B12 diffuse across the capillary membrane of adipose tissue at rates proportional to their respective free diffusion coefficients in water. The Pappenheimer equivalent pore radius estimate of 30 A and the Karnovsky interendothelial 40 A slit width are both defective in explaining the experimental data. The transendothelial channel system of fused vesicles (Simionescu, Simionescu and Palade 1975) is a possible structural equivalent for the present findings. The results support the hypothesis that capillaries of continuous type exhibit similar permeation characteristics regardless of the tissue in which they are located.