Manganese in apatites,chemical, ligand-field and electron paramagnetic resonance spectroscopy studies

Hydroxapatites precipitated with different amounts of carbonate and Mn²⁺ were studied. Infrared spectra, X-ray diffraction lattice parameters and thermal behaviour indicate that the presence of Mn²⁺ does not have any effect on the formation and properties of the carbonate apatites obtained. Interaction of apatite with a Mn²⁺-containing aqueous solution reveals that the molar uptake of Mn²⁺ by the apatite is higher than the Ca²⁺ released by it. Ligand-field and electron paramagnetic resonance spectroscopy results show that in Mn²⁺-doped Cd₅(PO₄)₃Cl, Mn²⁺ replaces Ca²⁺ in the apatite lattice, but in precipitated carbonate apatite it is in an MnO phase. The conclusion that Mn²⁺ in precipitated carbonate apatites is not incorporated in the apatite crystal is discussed in the light of the size differences between Mn²⁺ and Ca²⁺.     

Correlation of very late activation integrin and CD44 expression with extrarenal invasion and metastasis of renal cell carcinomas

Cell adhesion molecules mediate cell-cell and cell-matrix interactions, and they are thought to play an important role in tumor invasion and metastasis. Altered expression of integrins and CD44 in renal cell carcinoma has been recently demonstrated, but an association with invasive or metastatic behavior has not been reported. We examined very late activation (VLA) integrin and CD44 expression in 37 renal cell carcinomas and correlated adhesion molecule expression with multiple histological and clinical parameters. Most tumors exhibited positive staining for VLA3 (81%). Approximately one third of the tumors stained positively for VLA6 and CD44, and fewer (27%) were positive for VLA2. Only a few tumors were positive for VLA4 (8%) and VLA5 (14%). Most of the tumors exhibiting positive staining showed a combination of membranous and cytoplasmic staining patterns. Low-grade tumors positive for VLA6 showed a tendency for basilar staining of the tumor cells, whereas high-grade tumors exhibited diffuse cytoplasmic staining. All tumors exhibiting weak or strong positive staining for VLA4 or VLA5 showed extrarenal invasion or were known to have developed metastases at the time of nephrectomy. All tumors strongly positive for VLA2 or CD44 showed invasion beyond the renal capsule or metastases. In contrast to a previous study, no association was observed between positive staining and tumor grade. Nor were tumor size, architectural pattern, cell type, or DNA ploidy found to be associated with particular staining patterns. Although many of the invasive tumors showed no difference in VLA integrin or CD44 expression compared with tumors confined to the kidney, increased expression in some of them suggests that these cell adhesion molecules may contribute to the invasive or metastatic phenotype.     

Repeated exposure to the polychlorinated biphenyl (Aroclor 1254) elevates the basal serum levels of corticosterone but does not affect the stress-induced rise

Two-dimensional proton nuclear Overhauser effect (NOESY) spectra were obtained as a function of mixing time for two DNA dodecamers, 5'-CGCGAATTCGCG-3' and 5'-CGCAAATTTGCG-3', in aqueous solutions. The time evolution of cross-peak volumes was quantitatively analyzed based on the approximate solution of the relaxation/exchange equation over a range of mixing times from 30 to 150 ms. Inter-proton distances, involving exchangeable protons in key locations of the structures, were calculated and compared to the distances predicted by the crystal structures. These NMR-derived distances enhance the number of constraints, and their accuracy, for determination of solution structures of the two DNA dodecamers.     

Factors influencing outcome in consultations for chronic pelvic pain

We aimed to document the demographic and clinical characteristics of women referred by primary care physicians for investigation of chronic pelvic pain to a university hospital gynecology outpatient clinic and to test the hypothesis that specific patient features and the quality of doctor/patient communication at the initial consultation would influence pain outcomes. A clinical questionnaire, visual analog scales for pain, and instruments for hostility and the experience of the consultation were administered at the initial clinic attendance to 105 consecutive women. Follow-up pain scores were obtained 6 months later from 98 women. The mean hostility score was highly significantly elevated compared with normative data (p < 0.001). In a logistic regression model, a favorable patient rating of the initial consultation was associated with complete recovery at follow-up and interacted significantly with whether or not exercise was impaired (p < 0.005). For those in whom symptoms persisted, significant factors found by multiple regression models to predict continuing pain levels were the initial level of pain, the number of functions of daily life impaired, endometriosis, and the doctor who carried out the initial consultation. Patient hostility scores and the doctor's level of experience or gender were not significantly associated with continuing pain. This study highlights the importance of good communication as a basis for successful treatment of a group of hostile patients and indicates the influence in individual doctors of subtle attitudinal and personality factors that modify patients' experience of the medical consultation.     

Charge comparison protection of transmission lines-communicationsconcepts

The authors present the basic concepts of a digital approach to the communications requirements of a new transmission line protection scheme. Charge comparison is a new transmission line protection system. It compares local and remote quantities of charge, using a bidirectional communications channel. Charge comparison is a form of current differential relaying. Traditional current differential relaying schemes have three critical communications-related problems: protection is lost if the channel fails, a large channel capacity is required, and precise channel delay compensation is required. In large measure, charge comparison overcomes these three communications-related problems     

Ten-year outcomes for pathologic node-positive patients treated in RTOG 75-06

PURPOSE: This study was conducted to see what fraction of prostate cancer patients with biopsy-proven nodes are free of cancer 10 years after radiation treatment. METHODS AND MATERIALS: RTOG protocol #75-06 included 90 patients with biopsy-proven pelvic nodal involvement treated with radiation. They have been continuously follow-up since treatment. When feasible, current prostate-specific antigen (PSA) levels have been solicited from patients clinically cancer-free (no evidence of disease, NED) at 10 years, to confirm cure. RESULTS: The 10-year survival was 29%, the 10-year clinical NED survival 7%. PSA levels were obtained in 2 of 5 10-year clinical NED patients, they were both less than 0.8 ng/ml. The 2 proven cures were both clinical stage T-3, Gleason Score 6 and 8, and had 2 and 1 positive nodes, respectively. Multivariate analysis showed Gleason sum was significantly associated with clinical survival without disease. CONCLUSION: A small fraction of node-positive patients are cured at 10-year follow-up by radiation therapy (2 of 90 with PSA +3 of 90 by clinical endpoints). Innovative treatment programs should be directed at node-positive patients in an effort to improve the fraction cured.