Tracking capsule activation and crack healing in a microcapsule-based self-healing polymer.

Structural polymeric materials incorporating a microencapsulated liquid healing agent demonstrate the ability to autonomously heal cracks. Understanding how an advancing crack interacts with the microcapsules is critical to optimizing performance through tailoring the size, distribution and density of these capsules. For the first time, time-lapse synchrotron X-ray phase contrast computed tomography (CT) has been used to observe in three-dimensions (3D) the dynamic process of crack growth, microcapsule rupture and progressive release of solvent into a crack as it propagates and widens, providing unique insights into the activation and repair process. In this epoxy self-healing material, 150 µm diameter microcapsules within 400 µm of the crack plane are found to rupture and contribute to the healing process, their discharge quantified as a function of crack propagation and distance from the crack plane. Significantly, continued release of solvent takes place to repair the crack as it grows and progressively widens.

Calcitriol Reduces Albuminuria and Urinary Angiotensinogen Level in Renal Transplant Recipients.

BACKGROUND: Although nonhuman animal models have strongly suggested that vitamin D suppresses the renin-angiotensin system (RAS) and albuminuria, human data are largely lacking. The aim of this study was to examine the relationship between 25-hydroxyvitamin D [25-(OH)D] level and albuminuria and urinary angiotensinogen (UAGT) level in renal transplant recipients (RTRs). We also planned to investigate the effect of calcitriol treatment on albuminuria and UAGT level in these patients. METHODS AND RESULTS: A total of 124 nondiabetic RTRs participated in this study. UAGT level was positively correlated with the urinary albumin-creatinine ratio (UACR) in all patients (r = 0.855; P < .001). The mean UACR (P = .036) and UAGT/urinary creatinine (UCr) level (P = .02) were significantly higher in RTRs with low 25-(OH)D than in RTRs with normal 25-(OH)D level. RTRs with low 25-(OH)D level were randomized to receive either 0.25 µg/d calcitriol (n = 40) or placebo (n = 40). All of the parameters were assessed again 12 months later in both groups. The mean UACR (P = .014) and UAGT/UCr level (P = .012) were significantly lower in the calcitriol group than in the placebo group at the end of the study. CONCLUSIONS: Low 25-(OH)D status may be related to the elevation in albuminuria and UAGT, and calcitriol may have a beneficial effect on albuminuria through the inhibition of intrarenal RAS in RTRs.

Cardiac masses : Experience from a Turkish tertiary center of cardiology.

OBJECTIVE: Cardiac masses comprise a category that includes benign, malignant, and nontumoral mass lesions. The present study aims to share the findings relating to cardiac masses observed at our tertiary cardiology hospital in Turkey. METHODS: The records of patients who presented with cardiac masses and underwent surgery at our institute between 2006 and 2015, and whose tissue samples were sent to a pathology laboratory, were retrospectively reviewed in a consecutive manner. RESULTS: The study included 228 patients with an average age of 52.5 ± 17.3 years. Of the study's subjects, 95 (41.7%) were male and 133 (58.3%) female. The most commonly observed mass was myxoma in 68 patients (29.8%), of whom 20 (29.4%) were male and 48 (70.6%) female. The second most frequently detected mass was pannus, with 38 cases (16.7%) - 10 (26.3%) in males and 28 (73.7%) in females. The third most common cardiac mass was thrombus (16.2%), with 18 cases of thrombi in men (48.6%) and 19 (51.4%) in women. CONCLUSION: The most commonly observed cardiac mass was myxoma and most were localized in the left atrium. The second most frequently detected mass was pannus, which was mostly found on mitral mechanical prosthetic valves. Thrombi were the third most prevalent mass and were commonly localized in the right atrium.

Protective Effect of Micronized Purified Flavonoid Fraction on Ischemia/Reperfusion Injury of Rat Liver.

BACKGROUND: Flavonoids have been subjected to considerable investigation because of its antioxidant and anti-inflammatory properties. However, there is no previously reported study about its effect on hepatic ischemia/reperfusion (I/R). We investigated the effects of micronized purified flavonoid fraction (MPFF) on hepatic I/R injury in rats. METHODS: Thirty rats were recruited in the study as follows: group A, sham operation (n = 10); group B, I/R (n = 10); and group C, I/R+MPFF (n = 10). In group C, rats received (80 mg/kg/day) MPFF by gavage for 3 days before surgery, 30 minutes before ischemia and just before the reperfusion. Blood samples were taken, and serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were measured to assess liver functions. Liver tissues were taken for histological evaluation and to determine the total antioxidant capacity (TAC), catalase (CAT), total oxidant status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO). RESULTS: The present data showed a decrease in AST, ALT, and LDH levels in the MPFF-treated rats when compared with I/R group rats (P < .001 for all). In the MPFF-treated rats, tissue levels of TOS, OSI, and MPO were significantly lower than those in the I/R group (P < .01, P < .001, and P < .05, respectively). Increases in TAC and CAT levels were statistically significant in the MPFF-treated rats compared with the I/R group (P = .01 for both). On the other hand, MPFF attenuated histological alterations that were induced by I/R. CONCLUSIONS: The present study demonstrates that MPFF ameliorates I/R-induced liver damage, probably through antioxidant and anti-inflammatory properties.

Differences in nephrotoxicity risk and renal effects among anti-viral therapies against hepatitis B.

BACKGROUND: Results are conflicting with respect to the renal effects of anti-viral agents used for hepatitis B virus infection. AIM: To compare short and long-term renal effects in real-life settings and to determine risk factors for renal impairment during treatment. METHODS: 2221 treatment-naïve patients were enrolled. Among these, 895 (302 lamivudine, 27 telbivudine, 282 entecavir, 273 tenofovir and 11 adefovir initiated patients) had 'repeated measures' of creatinine (baseline, 1st, 6th, 12th and 24th month of treatment). Telbivudine and adefovir groups were excluded from further analysis because of the low number of patients. We calculated the glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease (MDRD) formula at each time point. Hypophosphataemia was also recorded. Risk factors for renal impairment were analysed. RESULTS: Tenofovir caused a decline in GFR at each time point when compared to baseline levels. However, lamivudine and entecavir did not change GFR. GFR-shifting from ≥90 to 60-89 mL/min/1.73 m(2) was comparable among groups. The proportion of patients whose baseline creatinine increased more than 25% was comparable among all anti-virals. GFR showed a decline in patients who switched from entecavir to tenofovir. One patient with compensated cirrhosis needed to change from tenofovir because of renal safety. Seven and three patients developed transient hypophosphataemia in the tenofovir and lamivudine groups, respectively. CONCLUSIONS: Although tenofovir caused a decline in GFR, differences between the anti-viral agents do not appear to be so impressive. In patients with and without renal risk factors at baseline, there is no impact of anti-virals, including tenofovir.

Is there any relationship between mean platelet volume and varicocele?

Mean platelet volume (MPV) is a parameter that is obtained from an automatic haemogram device during routine blood count and measures platelet reactivity. Increased platelet volume has been considered to be a risk factor for vascular diseases. The aim of this study was to evaluate the relationship between the presence of varicocele and the MPV, platelet count (PLT) and platelet distribution width (PDW) values. We included 264 patients with a diagnosis of varicocele in Group 1, and 220 patients with no varicocele in Group 2. The varicocele diagnosis was performed both with physical examination findings and colour Doppler ultrasonography (CDU). Mean platelet volume values were statistically significantly high (P < 0.001) whereas PLT and PDW values were statistically significantly low (P = 0.011), (P = 0.008) in the varicocele group compared with the control group respectively. However, no significant correlation was found between MPV and PDW in patients diagnosed with varicocele and the varicocele grade on examination and spermatic vein diameter on CDU. Mean platelet volume, which is used widely to measure the size of platelets and indicates platelet reactivity, can provide guidance in the investigation of varicocele pathophysiology and the relevant vascular pathologies.

Irritable bowel syndrome in patients with chronic pruritus of undetermined origin.

BACKGROUND: Chronic pruritus is an important distressing condition that is often refractory to treatment. Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that occurs without an organic cause. OBJECTIVES: We aimed to investigate the relationship between chronic pruritus of undetermined origin (CPUO) and IBS. METHODS: Eighty patients with chronic pruritus (CP) of undetermined origin and fifty healthy control subjects without pruritus were included into the study. All of the participants were examined by a gastroenterologist for concomitant IBS. RESULTS: The frequency of IBS was found higher in patients with CP of undetermined origin (P: 0.02), but we did not observe any significant association between pruritus intensity and either presence of IBS (P: 0.08) or the subtypes of the syndrome (P: 0.40). Furthermore, patients with CP of undetermined origin between 40 and 60 years, female gender and longer duration of the disease were found to be significantly associated with the presence of IBS (P: 0.02, P: 0.01 and P < 0.001). CONCLUSIONS: We found that the frequency of IBS was higher in patients with CP than in healthy controls. Our study is the first report about the relation between CP of undetermined origin and IBS. Further studies with larger numbers of the patients are needed to show association between IBS and CPUO using laboratory tests to define underlying diseases such as lactose intolerance, functional dyspepsia and emotional diseases.

Evaluation of three instruments for laparoscopic cholecystectomy: harmonic scalpel, bipolar vessel sealer, and conventional technique.

AIM: Laparoscopy is the gold standard procedure in the surgery of gall bladder. Harmonic scalpel and bipolar vessel sealer are the other instruments for laparoscopic cholecystectomy. The aim of this study is to compare the effectiveness and safety of the three instruments for laparoscopic cholecystectomy. METHODS: A total of 60 patients were included into the study. Patients were divided into three groups. In Group A, cystic duct and artery were sealed using laparoscopic clips and gall bladder was dissected from the hepatic bed using electrocautery. In Group B, cystic duct and artery were sealed using Harmonic scalpel and gall bladder was dissected from the hepatic bed using Harmonic scalpel. In Group C, cystic duct and artery were sealed using Bipolar vessel sealer and gall bladder was dissected from the hepatic bed using Bipolar vessel sealer. Groups were compared for the following parameters: duration of surgery, amount of drainage, cystic duct opening pressure and cost. RESULTS: The duration of surgery was 31.5 ± 11.1 minutes in Group B, 33.1 ± 10 minutes in Group A, and 36.5 ± 9.9 in Group C; and the difference between Group B and Group C was statistically significant (P<0.04). Cystic duct opening pressure was highest in Group A which was 324.0 ± 23.4 mmHg. For all of these 3 groups total cost was found to be 900$, 2900$, 1800$ for groups A, B, and C; respectively. CONCLUSION: In laparoscopic cholecystectomy different energy source instruments may be safe to use with a cautious dissection and sealing of the cystic duct.

Evaluation of Barrett's esophagus with CK7, CK20, p53, Ki67, and COX2 expressions using chromoendoscopical examination.

Barrett's esophagus (BE) is a complication of chronic gastroesophageal reflux disease and can be diagnosed when there is an endoscopically irregular Z-line and intestinal metaplasia (IM) in a biopsy obtained lower esophagus. It is still not clear whether IM in the gastric cardia or columnar mucosa without IM in the lower esophagus have any significance as BE, which is considered as preneoplastic. The aim of the study was to determine the immunohistochemical features of BE and columnar mucosa in the distal esophagus and also to evaluate the value of chromoendoscopy in the diagnosis of BE in a prospective manner. A total of 12 chromoendoscopic biopsies (six from normal-looking unstained esophagus and six from esophageal mucosa stained with methyl blue suspicious of BE) were taken from 111 cases who underwent endoscopy because of a variety of upper gastrointestinal symptoms. Immunohistochemical analysis was performed using CK7, CK20, p53, Ki67, and cyclooxygenase 2 (COX2). Of the 111 cases, 19 cases with carcinoma (nine adeno, six squamous, four undifferentiated carcinomas) and 17 cases with normal squamous epithelium were excluded, while 75 cases showing columnar epithelium, including 46 (61.3%) with IM and 29 (38,7%) without IM, were further evaluated immunohistochemically. CK7 was observed in surface, crypt, and glandular epithelium, whereas CK20 was expressed in surface and superficial crypt epithelium. No significant difference was observed between the Barrett and non-Barrett type of CK7/20 staining pattern (P > 0,05). Expression of p53 did not show any difference between BE and columnar mucosa without IM, whereas COX2 expression was significantly increased in BE (P < 0.05) in comparison with columnar mucosa without IM. Ki67 expression was significiantly higher both in upper and lower crypts in BE (P < 0.05). The present study showed that a Barrett pattern does not seem to exist; however, the analysis of COX2 expression and the Ki67 proliferation fraction by immunohistochemistry can be used to separate BE from non-Barrett's metaplasia of the distal esophagus. In our point of view, the immunohistochemical detection of p53 expression in Barrett's metaplasia stage is useless as a marker for early detection of high-risk patients.

Evaluation of hemostatic changes using n thromboelastography after crystalloid or colloid fluid administration during major orthopedic surgery

The effects of Ringer lactate, 6% hydroxyethyl starch (HES) (130/0.4) or 4% succinylated gelatin solutions on perioperative coagulability were measured by thromboelastography (TEG). Seventy-five patients (ASA I-III) who were to undergo major orthopedic procedures performed under epidural anesthesia were included in the study. Patients were randomly divided into three groups of 25 each for the administration of maintenance fluids: group RL (Ringer lactate), group HES (6% HES 130/0.4), and group JEL (4% gelofusine solution). Blood samples were obtained during the perioperative period before epidural anesthesia (t1, baseline), at the end of the surgery (t2), and 24 h after the operation (t3). TEG data, reaction time (R), coagulation time (K), angle value (α), and maximum amplitude (MA) were recorded. TEG parameters changed from normal values in all patients. In group RL, R and K times decreased compared to perioperative values while the α angle and MA increased (P < 0.05). In group HES, R and K times increased, however, the α angle and MA decreased (P < 0.05). In group JEL, R time increased (P < 0.05), but K time, α angle and MA did not change significantly. In the present study, RL, 6% HES (130/0.4) and 4% JEL solutions caused changes in the coagulation system of all patients as measured by TEG, but these changes remained within normal limits.

Evaluation of hemostatic changes using n thromboelastography after crystalloid or colloid fluid administration during major orthopedic surgery.

The effects of Ringer lactate, 6% hydroxyethyl starch (HES) (130/0.4) or 4% succinylated gelatin solutions on perioperative coagulability were measured by thromboelastography (TEG). Seventy-five patients (ASA I-III) who were to undergo major orthopedic procedures performed under epidural anesthesia were included in the study. Patients were randomly divided into three groups of 25 each for the administration of maintenance fluids: group RL (Ringer lactate), group HES (6% HES 130/0.4), and group JEL (4% gelofusine solution). Blood samples were obtained during the perioperative period before epidural anesthesia (t1, baseline), at the end of the surgery (t2), and 24 h after the operation (t3). TEG data, reaction time (R), coagulation time (K), angle value (α), and maximum amplitude (MA) were recorded. TEG parameters changed from normal values in all patients. In group RL, R and K times decreased compared to perioperative values while the α angle and MA increased (P < 0.05). In group HES, R and K times increased, however, the α angle and MA decreased (P < 0.05). In group JEL, R time increased (P < 0.05), but K time, α angle and MA did not change significantly. In the present study, RL, 6% HES (130/0.4) and 4% JEL solutions caused changes in the coagulation system of all patients as measured by TEG, but these changes remained within normal limits.