Comparison of stress transmission in the IMZ implant system with polyoxymethylene or titanium intramobile element: a finite element stress analysis.

Using the finite element method, this study modeled a 4.0 x 13.0-mm IMZ implant, restored with a cast gold crown, to examine the influence of the polyoxymethylene (POM) intramobile element (IME) on the transmission of vertical and oblique forces. Stress concentrations in the bone and in components of the implant system were much greater under a 30-degree load than under an equal vertical load. Stress transmission to bone occurred chiefly in the crestal region, and these stresses were not reduced when the IME was modeled in POM rather than in titanium. Maximum stress concentrations occurred in the fastening screw.     

Influences of central gray matter stimulation on thalamic neuron responses to high- and low-threshold stimulation of trigeminal nerve structures

Responses of the thalamic non-specific medial nuclei and relay ventral posteromedial nucleus neurons evoked by stimulation of the teeth pulp of A alpha and A sigma fibers of infraorbital nerve and caudal nucleus of the spinal trigeminal tract were studied in cats under thiopental-chloralose anesthesia. Three groups of neurons were revealed: low-threshold, high-threshold and convergent. In medial nuclei, 29% of neurons formed the low-threshold group, 12% made up the high-threshold group and 59% were convergent. In the ventral posteromedial nucleus 47% of neurons formed the low-threshold group, 4% made up the high-threshold group and 49% were convergent. Ninety per cent of the medial nuclei neurons and 79% of the ventral posteromedial nucleus neurons responded to stimulation of the caudal nucleus spinal trigeminal tract. The conditioning central gray matter stimulation could suppress responses of low-threshold, high-threshold and convergent neuron groups. In medial nuclei 100% of responses induced by stimulation of teeth pulp and A sigma fibers of the infraorbital nerve were completely suppressed and 86% of responses induced by stimulation of the A alpha fibers of the infraorbital nerve stimulation were also completely suppressed. In the ventral posteromedial nucleus 40% of responses induced by stimulation of teeth pulp and A sigma fibers of the infraorbital nerve were completely suppressed and 26.4% of responses induced by stimulation of the A alpha fibers of the infraorbital nerve were completely suppressed. Conditioning stimulation of the central gray matter suppressed responses evoked by stimulation of the caudal nucleus spinal trigeminal tract and in the most part neurons of the medial nuclei and neuron responses of the ventral posteromedial nucleus. The inhibitory influence of central gray matter stimulation on neuronal responses evoked by stimulation of the caudal nucleus spinal trigeminal tract shows that the central gray matter had a direct influence on the activity of thalamic neurons.     

Transvaginal sonography of cervical width and length during pregnancy.

Transvaginal ultrasonography has been proposed as a reliable method of assessing dimensions of the cervix. The purpose of the current investigation was to establish normative data for cervical width and length during pregnancy. This information may be helpful in predicting patients at risk for preterm birth. A transvaginal 5 or 7.5 MHz transducer was used on 132 consecutive low-risk pregnant women undergoing evaluation for gestational dating purposes. Even in cases of patient obesity or an empty bladder, high resolution was possible and permitted cervical measurement in all but one case. The external cervical width at the vaginal fornices was found to increase with advancing gestation (R = 0.512, P < 0.005). The cervical length from internal os to external os was found not to change with advancing gestation (R = 0.11, P = 0.30). Using these normative data, investigation is recommended to determine whether measuring cervical width and length is useful in predicting preterm labor and delivery.     

Comparison of fetal cerebellar measurements by two different techniques.

We examined 53 fetuses between 15 and 40 weeks of gestation with transverse and coronal sections of the head in order to evaluate the accuracy and reproducibility of the coronal cerebellar diameter. Intraobserver coefficient of variation was less than or equal to 2.2% and the mean interobserver difference was 2.2% (range, 0 to 6%). A positive linear correlation exists between transverse and coronal measurements (coronal diameter = 1.02 x transverse diameter - 0.48; R2 = 0.99; P less than 0.0001). We conclude that the coronal cerebellar diameter is reproducible and accurate and when indicated clinically can be used instead of the transverse cerebellar diameter when the latter is not obtainable because of fetal position.     

Experience in the combined treatment of different clinical forms of chronic bronchitis with new phytotherapeutic mixtures]

As many as 68 patients suffering from chronic bronchitis (CB) were subjected to combined treatment by new mixtures of medicinal herbs given per os and by inhalation. Administration of the first (antiseptic) or the second (broncholytic) mixture was determined by the clinical variant of CB. In 81% of cases, the method produced a beneficial effect, contributing to the shortening of the times of the patients' treatment in the hospital. The long-term results were also positive, allowing the simultaneous use of the phytotherapeutic mixtures per os and by inhalation in the treatment of CB patients.     

Age-linked prognostic categorization based on a new histologic grading system of neuroblastomas. A clinicopathologic study of 211 cases from the Pediatric Oncology Group.

Histologic sections (minimum of four sections per patient) from 211 patients with neuroblastoma were reviewed. The tumors were resected before therapy, which was standardized according to age and stage. Low mitotic rate (MR) (less than or equal to ten per ten high-power fields) and calcification emerged as the most significant prognostic features after statistical analysis by stepwise log-rank tests (P less than 0.0001 and P = 0.0065, respectively). Histologic Grades 1, 2, and 3 were defined on the basis of the presence of both, any one, or none of these two prognostic features, respectively (Grade 3 had absence of low MR, i.e., these tumors had high MR [greater than ten per ten high-power fields]). Statistically significant differences in survival were observed in the grades after adjusting for age and stage (P less than 0.001). The degree of differentiation, although significant by itself, was no longer significant after adjusting for the grades. Age groups (less than or equal to 1 versus greater than 1 year of age), which also emerged as an independent prognostic feature (P less than 0.001), were linked with the grades to define two risk groups as follows: (1) a low-risk (LR) group consisting of patients in both age groups with Grade 1 tumors and patients 1 year of age or younger with Grade 2 tumors and (2) a high-risk (HR) group consisting of patients older than 1 year of age with Grade 2 tumors and patients in both age groups with Grade 3 tumors. The difference in survival between LR (160 cases) and HR groups (51 cases) was statistically significant (P less than 0.001). Concordance between these LR and HR groups and the Shimada classification was observed in 84% of cases. The new histologic grading system has the following advantages: (1) use of familiar terminology and histologic features in the grading system and (2) relative ease of assessment because the degree of differentiation does not need to be determined. The grading system should be tested on a new data set with an appropriate histologic sample of similar size to confirm these results.     

Cellular and humoral reactivity pattern to the mycobacterial heat shock protein HSP65 in adjuvant arthritis susceptible and resistant Wistar rats.

We have analyzed the cellular and humoral immunity to the mycobacterial 65 KDa heat shock protein (hsp65) in a group of Freund's Adjuvant-immunized rats with a limited susceptibility to Adjuvant arthritis. According to the arthritis indices during the period of study (35 days), two different groups of rats could be distinguished; a) autoimmune Adjuvant arthritic rats (AA), and b) Non-arthritic animals (NA), including both rats which did not display any disease symptoms and rats suffering mild transient inflammation. The cellular response to the immunizing agent (Mycobacterium tuberculosis) or the mitogen Concanavalin A was comparable between both groups of rats. However, we detected an impaired cellular response to the individual hsp65 antigen in the animals that did not develop the disease. On the contrary, the level of hsp65-specific antibodies was much higher in NA animals than in AA rats suggesting a protective role for the hsp65 specific antibodies.     

Clonorchis-associated cholangiocarcinoma: a report of two cases with unusual manifestations.

Two cases of Clonorchis-associated cholangiocarcinoma are described along with their cholangiographic features to illustrate the spectrum of pathology ascribed to the injurious effects of the flukes on the bile duct epithelium. This includes adenomatous hyperplasia, extensive fibrosis, and carcinoma. The first case was also complicated by hepatic abscesses, left hepatic lobar atrophy, gastrobiliary and biliarocutaneous fistulae. The second case features an unusually dilated pancreatic duct containing pancreaticoliths that was found later to consist of hyperplastic bile duct epithelium, presumably carried by worm migration in the biliary tree. Liver sections from both patients showed typical features of hepatic clonorchiasis with the cancer. A knowledge of the wide spectrum of clinical presentation of clonorchiasis, particularly cholangiocarcinoma, might aid Western physicians in averting this serious sequela through prompt eradication of the helminthic infection and early recognition and treatment of its complications.     

Effect of diltiazem on silent myocardial ischemia]

Thirty-four patients with coronary heart disease who had silent myocardiac ischemic episodes as evidenced by long-term ECG monitoring were examined. Silent ST-segment elevations and depressions were encountered 2.7- and 4.9-fold as compared to manifest ones. The fact that the CHD patients had silent ST-segment depressions and/or prolonged high-amplitude silent ST-segment elevations suggests a grave severity of abnormal myocardial processes. There was a reduction in the number, duration of silent ST-segment elevations and depression episodes and in the amplitude of silent ST-segment depressions. This may indirectly indicate that the agent affects predominantly coronary blood flow and coronary vascular tone.