UV effect on the cathodo- and thermoluminescence properties of a gem-quality Cr-rich diaspore (α-AlOOH)

This work reports on the cathodoluminescence (CL) and thermoluminescence (TL) properties of gem-quality diaspore samples from Milas/Muğla (Turkey) after 100 h of ultraviolet-C (UVC) exposure. The UVC exposure induces significant changes in the intensity of the CL emission in the range of 400-800 nm that would be mainly associated with photo-oxidation processes of the impurities (Cr³⁺, Ti³⁺, Fe²⁺) that substitute for Al³⁺ in the diaspore (α-AlOOH) lattice. The UVC effect on the 400 nm-TL behavior of beta irradiated samples in the range of 0.1-8 Gy modifies the TL glow curves probably due to both photo-transfer process where electrons release from deeper to shallower traps and redox reactions involving, also, breakages-linkages of chemical bonds. Meanwhile, the 'as received' samples consist of three maxima centered at about 120, 180, and 234 °C, the 100 h UVC-irradiated samples display three maxima at 122, 220 and 270 °C. The physical trapping parameters (intensity and peak position, trap depth and pre-exponential factor) for each TL curve were estimated by using a computerized glow curve analysis program.

Circadian Variations in Natural Coagulation Inhibitors Protein C, Protein S and Antithrombin in Healthy Men: A Possible Association with Interleukin-6

Recent observations describe an increase in platelet aggregability and a decrease in fibrinolytic activity in the early morning hours. To determine whether anticoagulant proteins also show such a circadian variation we measured protein C (PC), protein S (PS), antithrombin (AT) and heparin cofactor-II (HC-II) levels on venous plasma samples taken from 10 healthy men at three-hour intervals throughout a 24-hour period. To investigate the possible temporal mapping of circadian periodicity, we also measured plasma levels of beta-thromboglobulin (β-TG) as an indicator of platelet activation, and interleukin-6 (IL-6) as one of the possible regulatory factors that drive this rhythm.

Blood samples were drawn at 6 a.m., 9 a.m., noon, 3 p.m., 6 p.m., 9 p.m. and midnight. PC, IL-6 and β-TG were measured by ELISA, PS and AT by latex immune assay and HC-II by chromogenic substrate method. A significant circadian variation was found in PC, PS, AT, β-TG and IL-6, but not in HC-II levels. PC, PS, IL-6 and β-TG were at their peaks at 6 a.m., and nadirs at a time from noon to midnight. AT peak was at 6 p.m. and nadir at noon. The regression of PS on IL-6 was significant. Although the fluctuations of PS and AT were within the normal ranges during the day, some PC levels of two subjects were below the lower normal limit (0.70).

These data indicate that PC, PS, and AT show a marked circadian periodicity as the other components of the blood coagulation and fibrinolytic system do. The similar trends in plasma concentrations of PC, PS, β-TG and IL-6 may be coincidental, but could reflect a common regulatory mechanism or an effect on each other. The clinical implications of these physiological changes in coagulation inhibitors and the role of IL-6 in the anticoagulant response deserve further studies.

Evaluated gas production cross-section data for natural titanium irradiated with protons at energies up to 3 GeV

Evaluated proton, deuteron, triton, 3He and 4He production cross-section data were prepared for natural titanium irradiated with protons at the energy up to 3 GeV. The evaluated data were obtained from the analysis of results of nuclear model calculations, available measured, and systematic data. The calculations of gas production cross-sections were carried out using the intranuclear cascade model (INC), the pre-equilibrium exciton model, geometry dependence hybrid (GDH) model, Weisskopf-Ewing (WE) model, and the Hauser-Feshbach model. CASCADE, TALYS, ALICE/ASH, and ALICE/HMS codes were used for calculations. Available experimental and systematic data, model calculations were used to evaluate gas production cross-section. The evaluation was carried out using statistical methods implemented in the BEKED code package developed at KIT/INR. The evaluated cross-sections were compared with the data from evaluated data libraries.

The efficacy of endoscopic ultrasonography in local staging of rectal tumors

BACKGROUND/AIMS

The purpose of this study was to research the efficacy and reliability of endoscopic rectal ultrasonography in local staging (T and N stages) of rectal tumors.

MATERIALS AND METHODS

This retrospective study was carried out by the Department of Gastroenterology, İzmir Atatürk Training and Research Hospital, which is tertiary level. Thirty-one patients with adenocarcinoma were included in the study. The patients found operable according to computed tomography underwent preoperative local staging by endoscopic ultrasonography. Radial endoscopic ultrasonography and T and N stages were evaluated.

RESULTS

It was observed that endoscopic rectal ultrasonography had 80.6% accuracy, 93.4% sensitivity, and 96.5% specificity in T stage; 70% accuracy, 70% sensitivity, and 86% specificity in the detection of presence of lymph node; and 76% accuracy, 100% sensitivity, and 22% specificity in the detection of the nature of lymph node.

CONCLUSIONS

In this study, it was observed that endoscopic rectal ultrasonography is an efficient and reliable method in the detection of local lymph node and the depth of invasion of rectal tumors (T staging), although it is not reliable enough to determine the characteristics of lymph nodes.

Does presence of common bile duct stones in patients with acute biliary pancreatitis affect the severity of illness or laboratory findings?

BACKGROUND/AIMS

To determine the effect of stone within the common bile duct, on the severity of acute biliary pancreatitis.

MATERIAL AND METHODS

This is a prospective and cross sectional study which was conducted at a tertiary care hospital including 103 patients. Serum biochemical values and white blood cell counts at the first 12th and 72nd hours of presentation were evaluated. The patients were grouped according to the presence or absence of common bile duct stones which were diagnosed by endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography. Besides, the patients were classified as mild and severe acute pancreatitis according to the data provided by computed tomography (Balthazar scoring) and clinical assessment and blood samples.

RESULTS

Among the 103 patients with acute biliary patients, radial endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography revealed stones and/or sludge within the common bile duct or ampulla in 41 (39.8%) patients. There was not any persistent common bile duct stone in 62 (60.2%) patients. Severe pancreatitis developed in 9 (22%) of 41 patients who were determined to have stones by endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography, and in 13 (21%) of 62 patients who were not. There was no difference in the incidence of progressing to severe acute biliary patients between patients with and without common bile duct stones (p=0.45).

CONCLUSION

Presence of common bile duct stones do not correlate with the severity of acute biliary pancreatitis.

Evaluation of flow and structure abnormalities of splanchnic system veins in cirrhotic patients without portal hypertension

AIM

The aim of this study was to evaluate hemodynamic and anatomic alterations of the splanchnic venous system and the efficiency and safety of color Doppler radial endosonography in the assessment of cirrhotic patients by comparing Child A cirrhotic patients without portal hypertension findings versus a non-cirrhotic group.

METHODS

The study was carried out between January 2009 and February 2010; the study population was 38 cirrhotic patients without portal hypertension and 140 control patients.

RESULTS

Hepatopedal flow was monophasic in all the control patients; the flow pattern was chaotic and irregular in 8% of the cirrhotic patients; in the cirrhotic patients the portal vein diameter was increased and the flow velocity reduced; no differences in flow volume were observed between the two groups. Splenic vein diameter and flow velocity were normal. In the majority of the Child A cirrhotic patients without portal hypertension, no changes were seen in portal vein diameter or flow volume; in some patients no significant increase portal vein diameter was observed and showed the flow volumes were unchanged.

CONCLUSION

Radial Doppler endosonography may be efficient and safe for assessing the splanchnic system.

Technetium-99m hexamethyl propylene amine oxime-labeled leukocyte scintigraphy at three different times in active ulcerative colitis: comparison with colonoscopy and clinico-biochemical parameters in the assessment of disease extension and severity

OBJECTIVE

In this study, our objective was to define the usefulness of technetium-99m hexamethyl propylene amine oxime (Tc-99m HMPAO)-labeled leukocyte scintigraphy at three different time points in the assessment of disease extension and severity in patients with active ulcerative colitis (UC).

METHODS

Twenty-one consecutive patients (10 women, 11 men; mean age 42.4 +/- 12 years) with active UC were prospectively studied. All patients were diagnosed by colonoscopy and histopathology prior to inclusion. Scintigraphy was performed at 1 h, 2 h, and 4 h after Tc-99m HMPAO-labeled leukocyte injection. Clinic-biochemical activity score, total colonoscopic activity score, and total scintigraphic activity score at 1 h, 2 h, and 4 h were calculated for each patient.

RESULTS

Sensitivity, specificity, and accuracy values of Tc-99m HMPAO-labeled leukocyte scintigraphy were calculated as follows, respectively: 1 h imaging 86%, 73%, and 83%; 2 h imaging 89%, 74%, and 86%; 4 h imaging 90%, 58%, and 83% in the detection of active inflammatory segments. Even though no statistically significant difference was found between 1 h, 2 h, and 4 h imaging with respect to the sensitivity, specificity of labeled leukocyte scintigraphy, the largest area under the curve value was found for 2 h imaging.

CONCLUSIONS

Tc-99m HMPAO-labeled leukocyte scintigraphy has been found to be correlated well with colonoscopy in the assessment of both the extension and severity of UC. We recommend 2 h scintigraphic imaging because it provides the largest area under the curve value and decreases the number of false-positive results.

Hepatic epithelioid hemangioendothelioma treated with orthotopic liver transplantation: a case report

Hepatic epithelioid hemangiendothelioma is a rare vascular tumor. The clinical course is unpredictable and different treatment modalities are offered depending on the patients condition. Orthotopic liver tranplantation is the choice of treatment in diffuse cases without metastases. A 32 year old woman was admitted to hospital with multiple mass lesions diagnosed by ultrasonography of the liver. Physical examination was normal except for a painless hepatomegaly, and her biochemical tests were within the normal range. Computed tomographic scanning showed the presence of multiple lesions in both lobes, some of which were accompanied by a small degree of calcification. Although these findings were suggestive of hepatic epithelioid hemangioendothelioma, ultrasonographic guided fine needle aspiration biopsy failed to diagnose the exact nature of the lesions. The diagnosis of hepatic epithelioid hemangioendothelioma was confirmed by diagnostic laparotomy and immunohistochemical examination of the specimen by FVIII-RAg, CD34 and CD 31 markers. The patient was treated by orthotopic liver transplantation and had no evidence of tumor 18 months after transplantation. The problems in differential diagnosis and treatment options are discussed in this report of the first case of this rare tumor, treated by orthotopic liver transplantation in Turkey.

The epidemiology of acute respiratory failure in critically ill patients(*)

STUDY OBJECTIVES

To describe the risk factors for the development of and mortality resulting from acute respiratory failure (ARF) in a large patient population.

DESIGN

A substudy of a prospective, multicenter, observational cohort study, which was designed to validate the sequential organ failure assessment score.

SETTING

Forty ICUs in 16 countries.

PATIENTS

All critically ill patients who were admitted to one of the participating ICUs during a 1-month period were observed until the end of their hospital course.

MEASUREMENTS AND RESULTS

Of the 1,449 patients who were enrolled into the study, 458 (32%) were admitted to an ICU with ARF, as defined by a PaO(2)/fraction of inspired oxygen ratio of < 200 mm Hg and the need for respiratory support. Patients who presented with ARF were older than the other patients (63 vs 57 years, respectively; p < 0.001) and more commonly had an infection (47% vs 20%, respectively; p < 0.001). The length of ICU stay was longer (6 vs 4 days, respectively; p < 0.001) and the ICU mortality rate was more than double (34% vs 16%, respectively; p < 0.001) in ARF patients compared to non-ARF patients. Of the 991 patients who were admitted to an ICU without ARF, 352 (35%) developed ARF later during the ICU stay. The independent risk factors for the development of ARF were infection developing in the ICU (odds ratio [OR], 7.59; 95% confidence interval [CI], 5.08 to 11.33) or present on ICU admission (OR, 2.3; 95% CI, 1.68 to 3.16), the presence of neurologic failure on ICU admission (OR, 2.73; 95% CI, 1.90 to 3.91), and older age (OR, 1.70; 95% CI, 1.30 to 2.22). Of all 810 patients with ARF, 253 (31%) died. The independent risk factors for death were multiple organ failure following ICU admission, history of hematologic malignancy, chronic renal failure or liver cirrhosis, the presence of circulatory shock on ICU admission, the presence of infection, and older age.

CONCLUSIONS

The present study stresses that ARF is common in the ICU (56% of all patients) and that a number of extrapulmonary factors are related to the risk of development of ARF and to mortality rate in these patients.

Intravenous single-dose tramadol versus meperidine for pain relief in renal colic

BACKGROUND AND OBJECTIVE

Comparison of the effectiveness of tramadol with meperidine given intravenously to emergency patients with suspected renal colic.

METHODS

A double-blind, randomized clinical trial was performed in the Emergency Department of a tertiary-care university hospital. Consecutive patients with suspected renal colic (n = 47) were randomized to receive intravenously an initial dose of tramadol 50 mg (n = 23) or meperidine 50 mg (n = 24). After 30 min, additional doses of meperidine 50 mg were given intravenously as a rescue medication in an open fashion. Pain relief was assessed using a 10 cm visual analogue scale, the primary outcomes being pain relief at 15 and 30 min after the analgesics. Secondary outcomes were the frequency of rescue meperidine use and the development of side-effects.

RESULTS

Visual analogue scale pain scores after 15 and 30 min decreased in both tramadol and meperidine groups (P < 0.05). However, pain relief was better in the meperidine group at the 15 and 30 min evaluations (P < 0.05). Only 11 patients (48%), initially receiving meperidine, needed more meperidine compared with 16 patients (67%) initially receiving tramadol. Both drugs were well tolerated with no adverse effects occurring in either group.

CONCLUSIONS

Meperidine 50 mg was superior to tramadol 50 mg for acute pain relief in patients with suspected renal colic when given intravenously. Because many patients in both groups received supplemental meperidine and the response to tramadol alone cannot be predicted, clinicians may want to choose higher doses of meperidine alone or other alternative combinations.

Magnesium efficacy in magnesium deficient and nondeficient patients with rapid ventricular response atrial fibrillation

We assessed the effect of magnesium sulphate (MgSO4) on lowering the rate in ventricular atrial fibrillation (AF), and evaluated the effect of this therapy in magnesium (Mg) deficient and nondeficient patients. This experimental clinical study was performed on 34 patients with rapid AF (ventricular rate [VR] > 120/minute) presenting to the emergency department of a tertiary care university hospital. Patients with systolic blood pressure < or = 100 mmHg, Hb level < or = 11.8, saO2 of < or = 96%, BUN > or = 40 or creatine > or = 1.8 were excluded (n = 15). Nineteen patients were given an initial 2 g MgSO4 bolus i.v. and a 1 g/hour continuous infusion over 6 hours. To evaluate the presence of Mg deficiency, urine was collected from the onset of treatment and continued for the next 24 hours, and the excretion rate of administered Mg was calculated. Ventricular rates were obtained at baseline, after MgSO4 bolus, and every 15 minutes for the first hour. The decrease in the VR was statistically significant at 15, 30 and 60 minutes after Mg therapy (p = 0.0025, p < 0.001, p > 0.001). There was no difference in the response to Mg therapy between Mg deficient and nondeficient patients at 15, 30 or 60 minutes after therapy (p = 0.41, p = 0.28, p = 0.08). It is concluded that i.v. MgSO4 has a statistically significant but clinically limited effect on VR and this effect did not differ between patients with and without Mg deficiency.

Strong vasopressor support may be futile in the intensive care unit patient with multiple organ failure

OBJECTIVE

The aim of the study was to determine the prognosis in patients who needed norepinephrine treatment in our institution in relation to the degree of organ failure and the evolution of the disease process.

DESIGN

Retrospective case note analysis of outcome of those patients who needed norepinephrine according to our institutional regimen.

PATIENTS

A total of 100 consecutive patients admitted to our 31-bed medical-surgical intensive care unit (ICU) who were treated with norepinephrine for severe hypotension and evidence of end-organ hypoperfusion unresponsive to both fluid resuscitation and dopamine treatment at 20 microg/kg/min.

MEASUREMENTS

The degree of organ dysfunction at the time of starting norepinephrine treatment was assessed by the sequential organ failure assessment (SOFA) score. The time before starting norepinephrine treatment was defined as the time elapsed between ICU admission and that of starting norepinephrine administration. The patients were defined as survivors or nonsurvivors according to their ICU outcome.

RESULTS

There were relationships between mortality and the degree of organ dysfunction and mortality and the duration of ICU stay before starting norepinephrine treatment. The mortality rate was 100% in the 30 patients with a total SOFA score of >12 and a delay before starting norepinephrine treatment of >1 day. The mortality rate of the other patients was 63%. The lowest mortality was seen in patients with lower SOFA scores and early norepinephrine administration after admission.

CONCLUSIONS

Both the time of starting norepinephrine treatment after admission to the ICU and the degree of organ dysfunction have an important bearing on subsequent outcome. Although norepinephrine may be a lifesaving catecholamine in some cases, its administration to patients who have already developed multiple organ failure during their stay in the ICU is associated with a poor outcome.

Circadian variations in natural coagulation inhibitors protein C, protein S and antithrombin in healthy men: a possible association with interleukin-6

Recent observations describe an increase in platelet aggregability and a decrease in fibrinolytic activity in the early morning hours. To determine whether anticoagulant proteins also show such a circadian variation we measured protein C (PC), protein S (PS), antithrombin (AT) and heparin cofactor-II (HC-II) levels on venous plasma samples taken from 10 healthy men at three-hour intervals throughout a 24-hour period. To investigate the possible temporal mapping of circadian periodicity, we also measured plasma levels of beta-thromboglobulin (beta-TG) as an indicator of platelet activation, and interleukin-6 (IL-6) as one of the possible regulatory factors that drive this rhythm. Blood samples were drawn at 6 a.m., 9 a.m., noon, 3 p.m., 6 p.m., 9 p.m. and midnight. PC, IL-6 and beta-TG were measured by ELISA, PS and AT by latex immune assay and HC-II by chromogenic substrate method. A significant circadian variation was found in PC, PS, AT, beta-TG and IL-6, but not in HC-II levels. PC, PS, IL-6 and beta-TG were at their peaks at 6 a.m., and nadirs at a time from noon to midnight. AT peak was at 6 p.m. and nadir at noon. The regression of PS on IL-6 was significant. Although the fluctuations of PS and AT were within the normal ranges during the day, some PC levels of two subjects were below the lower normal limit (0.70). These data indicate that PC, PS, and AT show a marked circadian periodicity as the other components of the blood coagulation and fibrinolytic system do. The similar trends in plasma concentrations of PC, PS, beta-TG and IL-6 may be coincidental, but could reflect a common regulatory mechanism or an effect on each other. The clinical implications of these physiological changes in coagulation inhibitors and the role of IL-6 in the anticoagulant response deserve further studies.