The effect of comonomer composition, silane heating, and filler type on aqueous TEGDMA leachability in model resin composites

Experimental composites using either bisGMA/TEGDMA or UEDMA/ TEGDMA matrices, quartz or barium glass fillers, and 2 different filler silanization methods were evaluated regarding monomer leachability in distilled water. The leached amount was detected and quantified using gas chromatography. The results showed that twice as much TEGDMA is leached from a bisGMA/TEGDMA based composite than from an UEDMA/ TEGDMA based composite, when both contain 50 wt% TEGDMA. The hypothesis suggested that the higher degree of cure of UEDMA/TEGDMA based composites would be reflected in a lower monomer leaching value, and this hypothesis was supported by the findings. Whether such a correlation exists within groups of UEDMA/TEGDMA based matrices having different degrees of cure was not determined and needs to be investigated in future studies. Variables such as filler composition and silane treatment did not affect the leaching values of TEGDMA in water. That finding suggests that future studies should target differences in matrices, and that the need for considering effects of filler composition and silane treatment methods should not receive the same priority.     

Rh血型不合新生儿溶血病检测方法及应用

产前检测Ｒｈ，Ｄ因子及抗人球蛋白（ｃｏｏｍｂｓ）试验是必要的。测定Ｒｈ，Ｄ因子及抗Ｄ滴度使用木瓜酶方法。通过对１１２６１例孕妇常规检查Ｒｈ，Ｄ因子，发现Ｄ阴性７４例。Ｒｈ，Ｄ阴性妇女占６．５‰。２２例Ｒｈ，Ｄ阴性的孕妇所分娩的新生儿均为Ｒｈ，Ｄ阳性。其中２例孕妇血清抗Ｄ滴度为１∶３２，病情严重，宫内输血无效，胎死宫内。初产妇１３例，占５９％。活产２０例，存活率９０％。Ｒｈ因子及抗人球蛋白试验方法简便、易行，一般医院均可进行。对有流产史、输血史的孕妇检查Ｒｈ因子是十分必要的。在有条件的医院，对Ｒｈ，Ｄ阴性的产妇分娩Ｒｈ，Ｄ阳性的新生儿之后，产妇应预防性注射抗Ｄ免疫球蛋白     

Transarterial embolization of vein of Galen aneurysmal malformation after unsuccessful stereotactic radiosurgery

The authors present three cases of vein of Galen aneurysmal malformations (VGAMs) diagnosed in infancy and submitted by the referring teams for stereotactic radiosurgery as the initial therapy (therapeutic doses ranging between 20–25 Gy and 40–50 Gy to the peak dose). After the conventional follow-up of 18–24 months, no change could be detected in the angioarchitecture of the lesions. All three cases were then referred for endovascular treatment and underwent embolization by the transarterial route using liquid adhesives (N-butyl cyanoacrylate). This resulted in complete anatomical exclusion of the lesion. Regardless of the theoretical efficiency of radiosurgery in the management of brain arteriovenous malformations, the present authors believe that transarterial embolization remains the treatment of choice in VGAMs. It offers a high rate of morphological cure and the best chances for normal neurocognitive development. The time required by radiosurgery to achieve a significant result is too long for developing and maturing brain and may not prevent the negative effects of the lesion, mainly in regard to hemo- and hydrodynamic disorders (atrophy, subcortical calcifications, etc.) created by the VGAM, thus leading to irreversible mental retardation.     

Plasminogen activator is involved in the hCG-induced neutrophil extravasation and vasopermeability increase in the rat testis

The role of proteolytic enzymes in the hCG-induced increase in testicular vasopermeability and neutrophil extravasation was studied using protease inhibitors. An intra-testicular injection of hCG together with incubation medium conditioned by polymorphonuclear leucocytes (PMNs) caused a significant increase in vasopermeability and a coincident extravasation of PMN's from the postcapillary venules in the rat testis. When p-aminobenzamidine, a serine protease inhibitor which inhibits urokinase-type plasminogen activator, was administered together with hCG in the incubation medium, both the permeability increase and PMN extravasation were prevented. Aprotinin, another serine protease inhibitor, and Eglin C, a specific neutrophil elastase and cathepsin G inhibitor were, however, without effect. None of these inhibitors caused any non-specific vascular effects in the testis at the concentrations used. These results support the concept that the hCG-induced increase in vasopermeability in the rat testis is related to extravasation of PMNs and suggest that urokinase-type plasminogen activator is involved in migration of these cells through the postcapillary venular walls.     

The Doppler guide wire: clinical applications in neuroendovascular treatment

The application of Doppler-tipped guide wires to measure blood flow velocity in coronary and peripheral arteries has been described previously as a valuable means of functional assessment in interventional cardiological procedures. In animal studies intravascular Doppler has been used in the cerebrovascular system, and this appears to be an important field of application for this new technique. We used intravascular haemodynamic monitoring by the Doppler guide wire during neuroendovascular procedures in patients with different cerebrovascular diseases and evaluated the clinical feasibility of the method. We found it a safe technique which complements morphological angiographic information with valuable functional data. Further studies may be expected to demonstrate the relation of flow parameters to clinical outcome. Received: 16 January 1996 Accepted: 30 January 1996     

Tubal patency and fertility outcome after expectant management of ectopic pregnancy

Objective: To study tubal patency and fertility outcome of patients with expectantly managed ectopic pregnancy (EP).

Design: A prospective study.

Setting: Department of Obstetrics and Gynecology, Turku University Central Hospital, Turku, Finland.

Patient(s): Thirty patients who wanted to become pregnant again were treated successfully by expectant management of EP.

Intervention(s): Patients were examined with posttreatment hysterosalpingography, and they filled out a questionnaire about their subsequent pregnancies.

Main Outcome Measure(s): Free passage through open lumen showing tubal patency; number of full-term pregnancies and EPs revealing relative rate of subsequent fertility.

Result(s): A free passage through the diseased tube was seen in 93% of the cases (28 of 30). Two of the 24 patients (8.4%) who wanted to become pregnant had an obstruction in the diseased tube. One (4.2%) of them had a normal opposite tube and later had a normal pregnancy. The other (4.2%) had an obstruction in both tubes and subsequently had a repeat EP. One of the 6 patients had an EP (this patient did not want to become pregnant and did not use contraception). However, her posttreatment hysterosalpingography was normal. In total, the subsequent pregnancy rate was 88% (21 of 24), and the rate of repeat EP was 4.2% (1 of 24).

Conclusion(s): Patients who are treated with expectant management have a good long-term fertility outcome. Spontaneous regression of EP does not lead to increased harm or damage to the tube, i.e., the risk for repeat EP is low.     

The short-term stability of student ratings of instruction in medical school

The purpose of this study was to assess the degree of consistency in student ratings of teacher effectiveness during the first year of medical school. Student ratings of teaching effectiveness represent a commonly used source of information that enters into the academic decision-making process. In medical school, student evaluations often represent a major source of information that is used in promotion and tenure decisions. It is essential that the precision of such ratings be ascertained so that decision-makers will know how much confidence to place in this source of information on teaching effectiveness. In this study, each member of a first-year medical school class was randomly assigned a two-digit identification number at the beginning of the spring semester, 1986. As the semester progressed students were asked to evaluate each full-time teacher in three major courses. Multiple instructors were utilized in each course (n = 10). Each teacher was evaluated immediately after lectures during the first (T1) and second (T2) halves of the course. Students evaluated the teacher a third time (T3) as part of the end-of-semester overall course evaluation. The teachers were evaluated on a short eight-item Likert-type scale that identified several key indicators of effective teaching. Students attached their anonymous identification numbers to individual ratings so that their responses could be matched in the analysis. The results indicate that medical students are only moderately consistent in the extent to which they evaluate teachers. This inconsistency varied by course and by instructors within courses.(ABSTRACT TRUNCATED AT 250 WORDS)     

Periodontal conditions among the middle-aged and the elderly in Hong Kong

Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984.