A physical approach to modify the hydraulic reactivity of α-tricalcium phosphate powder

A microsized α-tricalcium phosphate (α-TCP) powder was calcined at various temperatures (350 °C < T < 800 °C) for various durations (1–24 h) and the resulting physico-chemical and reactivity changes were measured. Without calcination, the α-TCP powder started reacting within minutes after contacting a 0.2 M Na₂HPO₄ solution as measured by isothermal calorimetry. The overall reaction was finished within a few days. After calcination at 350 °C  T  550 °C for 24 h, no significant changes in the crystalline composition, crystallite size, particle size or specific surface area were noticed. However, the powder reactivity was progressively changed. More specifically, the hydraulic reaction of the powders calcined at 500 and 550 °C only started after 2–3 h whereas the overall hydraulic reaction was only slightly postponed, suggesting that physical or chemical changes had occurred at the particle surface. As mainly physical changes were detected at the particle surface during calcination at 500 °C, it was speculated that the appearance of this reaction delay (= induction time) was due to the disappearance of surface defects during the calcination step, i.e. to the need to create surface defects to induce dissolution and hence reaction.     

Profile and significance of emergency colonic resections

The objectives of this study are to define the distinguishing features between elective and emergency colonic surgery. The records of adult patients who underwent elective and emergent colonic resection over a 4-year period were retrospectively reviewed. Univariate analysis was performed to compare outcomes for elective and emergency procedures and multiple logistic regression analysis was performed to identify the significant predictors of outcome. Three hundred and thirty-eight elective and 147 emergency colonic resections were performed. Diverticular disease was most common in the emergency group (43.5% vs 14.2%, P = 0.001) whereas malignancy predominated in the elective group (56.2% vs 5.4%, P = 0.001). The emergency group accounted for 54.7 per cent and 79.3 per cent of the total morbidity and mortality. Emergency colonic surgery has distinctive features and significance. Emergency surgery for colonic obstruction and total/subtotal resection are associated with higher morbidity and mortality. Diverticular disease compares favorably to other pathologies in postoperative outcome.     

Effect of chronic nicotine administration on the rat lung and liver: beneficial role of melatonin

Cigarette smoking is common in societies worldwide and has been identified as injurious to human health. The current study was designed to investigate the protective effect of melatonin, a radical scavenger and antioxidant, on nicotine-induced oxidative stress and morphological changes in the lung and liver of the rats. Three groups of male rats (controls, nicotine-treated [0.5 mg/kg], and nicotine plus melatonin [10 mg/kg] were used in this study. Levels of lipid peroxidation (LPO) products, superoxide dismutase (SOD) and glutathione (GSH) activity were measured in the tissue homogenates. Immunohistochemical and histological changes were also examined. The results revealed an increase in LPO and decrease in both SOD and GSH activity in the lung and liver homogenates on nicotine-treated rats. Melatonin administration to nicotine-treated rats attenuated the increase in LPO products and restored the SOD activity and GSH levels. The immunohistochemical and histological examination demonstrated marked increase in the immunoreactivity of nitrotyrosine, a specific "footprint" of peroxynitrite, and tissue damage in the lung and liver of nicotine-administered animals. Again, melatonin treatment reduced both nitrotyrosine reactivity and tissue damage associated with nicotine administration. These results, along with previous observations, suggest that melatonin may be useful in combating free radical-induced oxidative stress and tissue injury that is a result of nicotine toxicity.     

Selective spectrophotometric determination of phenolic β-lactam antibiotics

Two simple and selective spectrophotometric methods were developed for the quantitative determination of cefoperazone sodium, cefadroxil monohydrate, cefprozil anhydrous and amoxicillin trihydrate in pure forms as well as in their pharmaceutical formulations. The methods are based on the selective oxidation of these drugs with either Ce (IV) or Fe (III) in acid medium to give an intense yellow coloured product (λ_max=397 nm). The reaction conditions were studied and optimized. Beer's plots were obeyed in a general concentration range of 5–30 μg ml⁻¹ with correlation coefficients not less than 0.9979 for the four drugs with the two reagents. The methods are successfully applied to the analysis of pharmaceutical formulations containing amoxicillin, either alone or in combination with potassium clavulanate, flucloxacillin or dicloxacillin. They were also applied to the analysis of the other three studied drugs in vials, capsules, tablets and suspensions with good recovery; percent ranged from 99.7 (±0.46) to 100.32 (±1.05) in the Ce (IV) method and 99.6 (±0.50) to 100.3 (±1.32) in the Fe (III) method. Interferences from other antibiotics and additives products were investigated.     

SPOP,ZEB-1 and E-cadherin expression in clear cell renal cell carcinoma (cc-RCC): Clinicopathological and prognostic significance

Background

Clear cell renal cell carcinoma (cc-RCC), is a serious cancer regarding; its fatality, liability for metastases and chemoresistance, so identification of recent therapeutic targets to improve the patients prognosis is needed. SPOP is a BTB/POZ domain containing speckle-type POZ protein, has been identified as an E3 ubiquitin ligase component. ZEB1 is an essential epithelial mesenchymal transition (EMT) activator; E-cadherin is a cell adhesion protein that had been detected in normal epithelial cells membrane.

Gadolinium-enhanced MRI features of acute gouty arthritis on top of chronic gouty involvement in different joints

The aims of the current study are to describe gadolinium-enhanced MRI features of an acute flare of established gouty arthritis in different joints and to examine a possible association between serum uric acid and MRI signs indicative of ongoing inflammation and/or structural joint damage as well as association with disease characteristics and laboratory findings. Twenty-seven male patients with established chronic gout agreed to participate, mean age 47.6 years, and mean disease duration in months 43.2 (±31.8). For all patients, detailed demographic, disease characteristics, and laboratory findings were obtained and correlated with MRI findings. In 27 patients with established gout, a total of 50 MRI studies were performed of the following joints: feet joints (n?=?23), ankles (n?=?18), knees (n?=?5), and hand and wrist joints (n?=?4). MRI revealed capsular thickening in 19 patients, bone marrow edema (BME) in 15, soft tissue edema (STE) in 20, joint effusion in 21, bone erosions in 17, cartilaginous erosions in 4, and tenosynovitis in 9 cases. In 17 cases, tophaceous lesions were found. Post contrast MRI showed synovial thickening in seven cases. Positive correlations were observed between serum uric acid levels and the following MRI findings: capsular thickening (r?=?0.552, p?=?0.003), BME (r?=?0.668, p?≤?0.0001), STE (r?=?0.559, p?=?0.002), and tenosynovitis (r?=?0.513, p?=?0.006). Using MRI in chronic gout, important features can be detected like BME, minute cartilaginous erosions, and hypertrophic synovial inflammation in post contrast MR images. Serum uric acid (SUA) was positively correlated with capsular thickening, BME, STE, and tenosynovitis.     

Radiofrequency thermal ablation: the role of MR imaging in guiding and monitoring tumor therapy

Performing RFA procedures under MR imaging involves two distinct processes: interactive guidance of the RF electrode into the targeted tumor and monitoring the effect of therapy. The justification for using MR imaging for electrode guidance is quite similar to its use to guide biopsy and aspiration procedures, where MR imaging offers advantages related to superior soft tissue contrast, multiplanar capabilities, and high vascular conspicuity that facilitate safe and accurate guidance in selected lesions. The major contribution of MR imaging to thermal ablation procedures is its ability to monitor tissue changes associated with the heating process instantaneously, an attribute that is not paralleled by any other currently available imaging modality. Such ability facilitates a controlled approach to ablation by helping to detect inadequately treated tumor foci for subsequent interactive repositioning of the RF electrode during therapy. As such, MR imaging guidance and monitoring enable treatment of the entire tumor on a single-visit basis while avoiding undue overtreatment and preserving often critically needed organ function. Although knowledge of interventional MR imaging concepts and familiarity with its technology and with the related safety issues are indispensable for interventional radiologists attempting thermal ablation procedures in the MR imaging environment, understanding the tissue basis of necrosis imaging is becoming an essential part of the knowledge base for the larger sector of general radiologists who are required to interpret the follow-up MR imaging scans of the increasing number of thermal ablation patients.     

Analysis of survival after laparoscopy in women with endometrial carcinoma

BACKGROUND: The effect of the laparoscopic surgical approach on the survival of women with endometrial carcinoma remains unclear. The objectives of the current study were to assess the effect of laparoscopic surgery on the survival of women with early-stage endometrial carcinoma and to analyze the factors that affect such survival. METHODS: A retrospective review of women presenting with clinical stage I endometrial carcinoma (according to the 1988 International Federation of Gynecology and Obstetrics Staging System) was performed. Women treated with laparoscopy were compared with those treated with laparotomy with regard to their characteristics, surgical procedure, treatment, surgical stage, histology, tumor grade, and recurrence-free and overall survival. Factors affecting survival (surgical approach, histology, grade, and surgical stage) were evaluated using multivariate analysis and survival curves were constructed using Kaplan-Meier analyses. RESULTS: One hundred women underwent laparoscopy and 86 underwent laparotomy. Both groups were similar with regard to age, parity, menopausal status, lymphadenectomy, surgical stage, tumor grade, histology, and postoperative radiation therapy. Women who underwent laparoscopy and those who underwent laparotomy had similar 2-year and 5-year estimated recurrence-free survival rates (93% vs. 94% and 90% vs. 92%, respectively), as well as similar 2-year and 5-year overall survival rates (98% vs. 96% and 92% vs. 92%, respectively). There was no apparent difference with regard to the sites of recurrence between both groups. In univariate and multivariate analyses, surgical stage, tumor grade, and histology (but not the surgical approach) were found to have a significant effect on survival. CONCLUSIONS: Although longer follow-up is needed, the survival of women with early-stage endometrial carcinoma does not appear to be worsened by laparoscopy. Surgical stage, tumor histology, and tumor grade were found to significantly affect survival regardless of the surgical approach used.