Pathophysiology and management of angiotensin-converting enzyme inhibitor-associated refractory hypotension during the perioperative period.

Hypertension is a common chronic condition in many patients requiring anesthesia. Pharmacologic therapy is a mainstay of treatment for hypertension, with angiotensin-converting enzyme (ACE) inhibitors being a frequently prescribed class of drugs. The American College of Cardiology and American Heart Association 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery provide information on many drug classes used in the treatment of hypertension; noticeably absent is a guideline for ACE inhibitors. Literature demonstrates that practice standards vary on whether ACE inhibitor regimens are continued or withheld during the preoperative period. When ACE inhibitor therapy is continued in patients undergoing general anesthesia, varying degrees of hypotension can be seen depending on confounding patient variables and the type of surgical procedure. In some instances, this hypotension can be refractory to traditional interventions such as administration of a fluid bolus, ephedrine, or phenylephrine. Vasopressin and methylene blue have been found to be effective treatments for ACE inhibitor-associated refractory hypotension. With the prevalence of hypertension and use of ACE inhibitors, anesthesia providers are likely to encounter refractory hypotension of this nature. The absence of guidelines regarding ACE inhibitors in the perioperative period contributes to a lack of consistency in practice.

Expression of the ELAV-like protein HuR in human prostate carcinoma is an indicator of disease relapse and linked to COX-2 expression.

The human ELAV-like protein HuR is involved in the stabilization of the mRNAs of a group of genes implicated in the regulation of cellular growth, angiogenesis and rapid inflammatory response. HuR is a nuclear shuttling protein, translocating bound mRNAs from the nucleus to the cytoplasm. We have previously observed an increased expression of cyclooxygenase-2 (COX-2) in prostate cancer while cell culture studies have shown that HuR stabilizes the mRNA of COX-2. Based on these mechanistic data, we aimed to investigate the role of HuR in prostate cancer by a tissue-based analysis combined with functional evaluation using a cell culture approach. Investigating 104 primary prostate carcinomas by immunohistochemistry, we found HuR expression to be shifted from a nuclear staining in normal prostate glands to a cytoplasmic staining in carcinoma tissue (p<0.0001). Cytoplasmic HuR expression was significantly correlated with COX-2 expression (p=0.005). Loss of nuclear HuR expression was an indicator of earlier PSA-relapse both in univariate (p=0.04) and multivariate survival analysis (p=0.04). HuR inhibition by Leptomycin B reduced the inducibility of COX-2 in PC-3 prostate cancer cells. We found that the subcellular localization of HuR is deregulated in a subset of prostate carcinomas, and that this deregulation is linked to an altered expression of the tumorigenic COX-2 protein as well as to an adverse patient prognosis. Our results point to a potential prognostic role of HuR expression in prostate cancer diagnostics and propose HuR as a future therapeutic target in prostate cancer therapy.

Clinical and radiographic evaluation of patients receiving both tooth- and implant-supported prosthodontic treatment after 5 years of function.

PURPOSE: The aim of this research was to assess survival and complication rates of tooth- and implant-supported fixed dental prostheses (FDPs) and single crowns (SCs) after 5 years of function in a specific patient population group who underwent comprehensive prosthetic treatment. MATERIALS AND METHODS: This retrospective study included a convenience sample of 52 patients who met specific inclusion and exclusion criteria and were treated during two specific courses as part of the undergraduate curriculum. The patients' prosthodontic treatment comprised 296 tooth-supported and 37 implant-supported SCs together with 76 tooth-supported and 15 implant-supported FDPs. Pre- and posttreatment clinical examinations included screening for biologic and technical complications, probing pocket depth, bleeding on probing (BoP), and plaque control record (PCR) as well as intraoral radiographs. Information was obtained from the patients about dental hygiene and dental visits, treated complications, and patient satisfaction during the observation period. Descriptive statistics were employed. RESULTS: Forty-five patients were followed for a mean observation period of 5.26 ± 0.47 years. The survival rates were 99.0% for tooth-supported SCs, 98.7% for tooth-supported FDPs, and 100% for implant-supported FDPs and SCs. Loss of vitality was observed in 2.9% of all abutment teeth deemed to be vital initially. Endodontic complications occurred in 5% and root fracture in 2.5% of nonvital abutment teeth. Caries was found in 0.4% of abutments. No framework or implant fractures were observed, but fracture of the veneering ceramic affected 3.8% of FDPs. The mean BoP was 21.5% ± 9.9%, and the mean PCR was 22.8% ± 16.5%. A high satisfaction rating was provided by 82.2% of patients. CONCLUSIONS: High survival and relatively few complication rates were observed for all prescribed FDPs over the observation period.

Influence of white and gray endodontic posts on color changes of tooth roots, composite cores, and all-ceramic crowns.

OBJECTIVE: To evaluate whether post materials affect the color of roots, composite cores, and all-ceramic crowns. METHOD AND MATERIALS: Forty extracted human incisors were divided into four groups. White posts made of zirconia (Zi) or glass fiber (Gf) and gray posts made of titanium (Ti) or carbon fiber (Cf) were randomly assigned to the roots. Composite cores and glass-ceramic crowns were made. The color of the roots, cores, and crowns was captured (Spectroshade). The mean color difference (mDeltaE) among the groups was calculated for the following comparisons: A--root: empty root versus post and core; B--root: post and core with and without cement; C--core: white versus gray posts and cores; D--lower third of crown versus original ceramic ingot; E--center of crown versus ingot. Statistical analysis was performed by ANOVA, Kruskal-Wallis, and Sheffe tests. RESULTS: White, as well as gray posts, induced little changes of the root color (A, B). Gray posts led to a significant discoloration of the cores (C: mDeltaEZi 2.0+/-0.7, mDeltaEGf 1.5+/-0.6, mDeltaETi 12.9+/-5.9, mDeltaECf 11.2+/-5.3; P<.0001, Kruskal-Wallis) resulting in a grayish discoloration of the crowns' lower thirds (D: mDeltaEZi 5.7+/-0.8, mDeltaEGf 6.0+/-1.2, mDeltaETi 3.5+/-1.1, mDeltaECf 3.9+/-0.9; P<.0001, Kruskal-Wallis). In the center of the crowns, all posts and cores induced a similar color difference (E). CONCLUSION: A grayish gingival shadowing cannot be reduced with white posts. In combination with glass-ceramic crowns, white posts and cores are esthetically beneficial.

Lipid globule size in total nutrient admixtures prepared in three-chamber plastic bags.

PURPOSE: The stability of injectable lipid emulsions in three-chamber plastic (3CP) bags, applying the globule-size limits established by United States Pharmacopeia ( USP ) chapter 729, was studied. METHODS: A total of five premixed total nutrient admixture (TNA) products packaged in 3CP bags from two different lipid manufacturers containing either 20% soybean oil or a mixture of soybean oil and medium-chain-triglyceride oil as injectable lipid emulsions were tested. Two low-osmolarity 3CP bags and three high-osmolarity 3CP bags were studied. All products were tested with the addition of trace elements and multivitamins. All additive conditions (with and without electrolytes) were tested in triplicate at time 0 (immediately after mixing) and at 6, 24, 30, and 48 hours after mixing; the bags were stored at 24-26 degrees C. All additives were equally distributed in each bag for comparative testing, applying both globule sizing methods outlined in USP chapter 729. RESULTS: Of the bags tested, all bags from one manufacturer were coarse emulsions, showing signs of significant growth in the large-diameter tail when mixed as a TNA formulation and failing the limits set by method II of USP chapter 729 from the outset and throughout the study, while the bags from the other manufacturer were fine emulsions and met these limits. Of the bags that failed, significant instability was noted in one series containing additional electrolytes. CONCLUSION: Injectable lipid emulsions provided in 3CP bags that did not meet the globule-size limits of USP chapter 729 produced coarser TNA formulations than emulsions that met the USP limits.

Misfit of suprastructures on implants processed by electrical discharge machining or the Cresco method.

OBJECTIVE: To assess the accuracy of fit of frameworks on implants processed with electrical discharge machining (EDM) or the Cresco technique (Astra Tech). METHOD AND MATERIALS: On 12 identical master casts with implants at positions 9(21), 11(23), and 13(25), high-gold alloy frameworks were produced by standard casting procedure. Six frameworks were used for the Cresco technique (group CRE) by employing specific fixed partial denture supports. The remaining 6 frameworks were cast with prefabricated gold copings and served as control. The finished frameworks were screwed onto implant 25 of the corresponding master cast. Dimensions of the marginal gaps were measured at 4 locations on each implant under the scanning electron microscope, applying the replica technique. Subsequently, the control group was processed by EDM (SAE EDM 2000) (group EDM) and analyzed alike. Statistical analysis of the results was performed with Kruskal-Wallis and Mann-Whitney U tests. RESULTS: The mean marginal gaps were measured as follows (CRE/EDM/control): position 25: 0.0 microm/1.0 +/- 1.6 microm/1.5 +/- 2.1 microm; position 23: 5.2 +/- 5.6 microm/18.7 +/- 29.3 microm/23.6 +/- 30.7 microm; and position 21: 36.0 +/- 21.6 microm/40.7 +/- 31.0 microm/46.0 +/- 41.1 microm. The only statistically significant difference was found at location 23 between group CRE on one side and both group EDM and control on the other side. The strong increase of misfit for group CRE from location 23 to location 21 indicates that laser welding is the crucial parameter in this technique. CONCLUSION: The Cresco technique has a potential to reduce the marginal gap between implants and suprastructures.

Overexpression of cyclooxygenase-2 in human prostate carcinoma and prostatic intraepithelial neoplasia-association with increased expression of Polo-like kinase-1.

BACKGROUND: Cyclooxygenases (COX) as well as Polo-like kinases (PLK) are involved in proliferation and cell cycle regulation and have been suggested for preventive and therapeutic approaches in prostate carcinoma. METHODS: In this study, we studied expression and prognostic impact of COX-2 in invasive prostate carcinoma, prostatic intraepithelial neoplasia (PIN), atrophic glands, and normal prostatic glands, and investigated the association between COX-2 and PLK-1. RESULTS: We observed a positivity for COX-2 in 72.1% of PIN and in 44.7% of prostate carcinomas with an overexpression of COX-2 in prostate cancer and PIN compared to benign prostatic tissue (P < 0.0005). Furthermore, we observed a strong correlation between expression of PLK-1 and COX-2 (P < 0.0005). CONCLUSIONS: To our knowledge, this is the first report of a correlation between COX-2 and PLK-1 in a malignant tumor. COX-2 and PLK-1 may be interesting targets for new molecular therapies in prostate cancer.