Determination of ultra-low concentrations of gaseous 14C-bearing hydrocarbons produced during corrosion of irradiated steel using accelerator mass spectrometry.

Compound-specific radiocarbon analysis (CSRA) was developed to identify and quantify gaseous 14C-bearing carbon compounds at the pico- to femtomolar concentration range and employed in a corrosion experiment with small specimens of irradiated steel. The approach is based on gas chromatographic separation of single 14C-bearing carbon compounds, their oxidation to 14CO2, sampling with a custom-made fraction collector and quantification by accelerator mass spectrometry (AMS). In addition to CSRA, a method allowing the quantification of the total 14C content of the gas phase was developed and tested. After validation of the two set-ups with standards, the gaseous 14C-bearing carbon compounds produced during alkaline anoxic corrosion of irradiated steel were quantified. Small hydrocarbons (HCs) like methane (14CH4) and ethane (14C2H6) were the only 14C-bearing compounds identified in the gas phase above the detection limit. 14CH4 was the main species (on average 5.4 × 10-14 mol L-1 gas) and contributed >90% to the total 14C content, whereas the concentration of 14C2H6 was much lower (7.9 × 10-16 mol L-1 gas). To our knowledge, this is the first study reporting CSRA of gaseous 14C-bearing HCs produced during anoxic corrosion of irradiated metallic radioactive waste at ultra-low concentrations.

Analysis of 14C-bearing compounds released by the corrosion of irradiated steel using accelerator mass spectrometry.

The combination of ion chromatography (IC) with accelerator mass spectrometry (AMS) was developed to determine the speciation of 14C-(radiocarbon) bearing organic compounds in the femto to pico molar concentration range. The development of this compound-specific radiocarbon analysis (CSRA) of carboxylic acids is reported and the application of the method on a leaching solution from neutron-irradiated steel is demonstrated. The background and the dynamic range of the AMS-based method were quantified. On using 14C-labelled standards, the measurements demonstrate the repeatability of the analytical method and the reproducible recovery of the main target carboxylic acids (i.e., acetate, formate, malonate, and oxalate). The detection limit was determined to be in the mid fmol 14C per L level while the dynamic range of the analytical method covers three orders of magnitude from the low fmol to the mid pmol 14C per L level. Cross contamination was found to be negligible during IC fractionation and was accounted for during eluate processing and 14C detection by AMS. The 14C-bearing carboxylates released from an irradiated steel nut into an alkaline leaching solution were analysed using the CSRA-based analytical method with the aim to check the applicability of the approach and develop appropriate sample preparation. The concentrations of 14C-bearing formate and acetate, the main organic corrosion products, were at a low pmol 14C per L level for convenient dimensions of the alkaline leaching experiment which demonstrates that compound-specific 14C AMS is an extremely sensitive analytical method for analysing 14C-bearing compounds. The content of total organic 14C in solution (TO14C) determined by the direct measurement of an aliquot of the leaching solution agrees well with the sum of the 14C concentrations of the individual carboxylates within the uncertainty of the data. Furthermore, the TO14C content is in good agreement with the calculated value using the corrosion rate determined from the 60Co release and the 14C inventory of the irradiated steel specimen.

Periodontal treatment in private dental practice: a case-based survey.

BACKGROUND: This study aimed to assess the management and referral patterns of Victorian general dental practitioners based on periodontal diagnosis. METHODS: Following ethics approval, Victorian general dental practitioners were invited to complete five randomized text-based periodontitis scenario questionnaires. Based on their diagnosis, respondents were asked for their management options and asked to specify who would perform these treatments. Respondents were also asked about referral procedures. RESULTS: One hundred and thirty-five dentists attempted the survey. Most were in group practice and based in Melbourne. Of the total respondents, 22.5% worked in a practice employing a hygienist. The management of periodontal disease was appropriate, and treatment options increased with severity. As severity increased, patients were more likely to be referred to a periodontist. Periodontal services referred by general dentists to dental hygienists increased with the number of days the hygienists worked within a practice. Over- and underdiagnosis did not markedly affect management. The recommendation of antibiotics, mouthwashes and periodontal surgery varied depending on year and school of graduation. CONCLUSIONS: The general dentists that completed the survey are managing periodontal conditions appropriately and according to current guidelines.

Periodontal diagnosis in private dental practice: a case-based survey.

BACKGROUND: Despite the prevalence of periodontitis in Australia, there are few reports regarding periodontal diagnosis and therapies in the general dental practice setting. This study aimed to assess the degree of diagnostic accuracy in periodontal cases of Victorian general dental practitioners. METHODS: Following ethics approval, dentists were invited to complete a scenario-based questionnaire on the Australian Dental Association Victorian Branch (ADAVB) website. Five text-based clinical scenarios (from a total of 10) were randomly presented, representing patients with a range of disease levels from periodontal health/gingivitis to severe periodontitis, and respondents were asked what examinations they would usually perform. Based upon the presented results of periodontal and radiographic examinations, a periodontal diagnosis was requested. RESULTS: One hundred and thirty-five dentists attempted the survey. Most were in group practice and based in Melbourne; 22.5% of respondents worked in a practice employing a hygienist. The clinical parameters most commonly measured to diagnose periodontal disease were pocket depth and mobility. The majority of respondents diagnosed health, gingivitis and mild periodontitis correctly compared to American Academy of Periodontology guidelines. However, moderate periodontitis tended to be diagnosed as severe. CONCLUSIONS: Dentists in Victoria used appropriate clinical parameters when assessing periodontal disease and were generally accurate in their diagnoses. There is a need for consensus regarding diagnostic definitions.

Systemic alterations in concentrations and distribution of plasma phospholipids in prostate cancer patients.

The relationship between plasma levels of total phospholipids (PL) and/or PL fractions and neoplastic diseases are not fully understood. Therefore, the aim of this study was to analyze concentrations and distribution of plasma phospholipids in patients with prostate cancer (PCa) related to the Gleason score, clinical stage and pathologic grade of prostate cancer. We analyzed plasma phospholipids in 57 newly diagnosed, untreated PCa patients and in 43 age-matched healthy male subjects. Significantly lower (P < 0.01) levels of total plasma PL and all PL classes were found in PCa patients when compared with healthy subjects. The relative concentrations of PL fractions were also changed. Further decrease of total PL and PL fractions was found related to an increase of clinical stadium, pathologic grade, and Gleason score, with phosphatidylethanolamine as the most sensitive plasma PL, the level of which significantly decreased even at the first stage of PCa. Our results showed an altered plasma PL profile in PCa patients, which may contribute to monitoring of the disease progression.

Performance of lactating dairy cows fed corn as whole plant silage and grain produced from genetically modified corn containing event DAS-59122-7 compared to a nontransgenic, near-isogenic control.

The nutritional equivalency of grain plus whole plant silage from genetically modified corn plants containing the DAS-59122-7 (59122) event expressing the Cry34Ab1 and Cry35Ab1 proteins to grain and silage from a near-isogenic corn hybrid without this trait (control) was assessed using lactating dairy cows. Corn plants with event 59122 are resistant to western corn rootworm and tolerant to the herbicide active ingredient glufosinate-ammonium. Effects on feed intake, milk production, and milk composition were determined. The 59122 grain and the control grain were produced in 2005 from isolated plots in Richland, Iowa. Whole plant corn silage for the 59122 and control treatments were grown in isolated plots at the Kansas State University Dairy Center and ensiled in Ag-Bags. Thirty lactating Holstein cows blocked by lactation number, day of lactation, and previous energy-corrected milk production were used in a switchback design. All cows were fed diets that contained 22.7% grain plus 21.3% whole plant silage from either the 59122 or the control hybrid, in addition to 21% wet corn gluten feed, 12.3% protein mix, 8.0% whole cottonseed, and 14.7% alfalfa hay. Each period of the switchback trial included 2 wk for diet adjustment followed by 4 wk for data and sample collection. Milk samples (a.m. and p.m.) collected from 2 consecutive milkings of each collection wk were analyzed for fat, protein, lactose, solids-not-fat, milk urea nitrogen, and somatic cell count. Percentages of milk fat, protein, lactose, and solids-not-fat were not affected by dietary treatment. Yields of milk, 4% fat-corrected milk, energy-corrected milk, solids-corrected milk, and the concentrations and yields of milk fat, milk protein, milk solids, and milk lactose were not significantly different between treatments. Efficiencies of milk, fat-corrected milk, energy-corrected milk, and solids-corrected milk production also were not different when cows were fed crops from 59122 than when they were fed the control hybrid. Milk production efficiency averaged 1.48 and 1.50 kg/kg of dry matter intake for cows fed diets containing the control and 59122 corn, respectively. These data indicate that the nutritional value for milk production was not different between a diet containing grain plus whole plant corn silage produced from a 59122 corn hybrid versus a diet containing grain and corn silage from its near-isogenic control corn hybrid.

Bilateral ureteral obstruction due to primary myelofibrosis caused hyperuricaemia.

In healthy population, uric acid comprises the major component of 10-20% of renal stones. Extreme hiperuricaemia is seen in cancer patients with tumour lysis syndrome (TLS) which is classically associated with haematological malignancies with rapid tumour growth rates such as acute lymphoid leukaemia and high grade lymphomas. Primary melofibrosis (Agnogenic myeloid metaplasia-AMM) is a chronic myeloproliferative disease characterized by splenomegaly, a leukoerythroblastic blood picture, teardrop poikilocytosis and varying degrees of marrow fibrosis. Due to the increased extramedullary haematopoiesis, hiperuricemia may occur. However, TLS in patients with AMM is, according to the available literature, described just in one patient. In this paper we present a case of a 47-year-old male patient who was admitted to the hospital with symptoms of fatigue and small amount of urine, and clinical signs of plethora and enlarged spleen. The laboratory findings showed leuko-and erythrocytosis, increased levels of urea-BUN (32 mmol/l) and creatinine (766 mmol/l) as well as uric acid (920 mmol/l). The immediate abdominal ultrasound confirmed extreme splenomegaly, but also showed bilateral hydronephrosis of grade II-III with two stones in proximal part of right ureter and one in proximal part of left ureter as well as empty bladder. Stones were not seen on plain film. Since the patient was in complete anuria, with further rapid elevation of BUN and creatinine levels, bilateral ureteral stents were applicated together with extensive hydration, urine alkalization and administration of allopurinol which resulted in the complete recovery of kidney function. The bone marrow biopsy was also performed and histopathological diagnosis was: Hypercellulary phase of AMM.

Lipid profile as a prognostic factor in cancer patients.

PURPOSE: The relationship between plasma lipid levels and neoplastic diseases is still unclear. The aim of this study was to analyse the lipid profile of individuals with non-Hodgkin's lymphoma (NHL) or prostate carcinoma (CaP) and to follow serum lipid levels changes in NHL patients according to their response to chemotherapy. PATIENTS AND METHODS: Forty-seven patients with NHL, 57 patients with CaP, two control groups composed of 29 and 43 age- and sex-matched healthy adults, related to NHL and CaP patients, respectively, were included in the study. Follow-up studies of NHL patients were carried out after the 3rd and 6th cycle of chemotherapy. RESULTS: Initial plasma cholesterol (Chol), HDL-cholesterol (HDL-Chol) and phospholipids (PL) values were significantly lower in patients with NHL or CaP than in controls. Following chemotherapy, we noticed a progressive increase in lipid levels in NHL patients with complete remission (CR) and stable disease (SD), and further decrease in patients with the disease progression. CONCLUSION: Decreased plasma Chol, HDL-Chol and PL levels of patients with NHL or CaP can be considered as non-specific prognostic parameters in patients with these malignancies.

[Urethral syndrome in men--chronic pelvic pain syndrome].

INTRODUCTION: Chronic pelvic pain syndrome (CPPS) is defined as pelvis minor pain of nonmalignant nature repeating in different time intervals. Urethral syndrome (US) represents a most poorly defined entity within CPPS. OBJECTIVE: The estimation of US influence on quality-of-life as well as the determination of the way of treatment and therapy optimal length. MATERIAL AND METHODS: A prospective one-year study included 166 men with CPPS, median age of 54 years; they were monitored clinically. During the patient monitoring the NIH-CPSI questionnaire (National Institute of Health-Chronic Prostatis Symptom Index) was used. US was diagnosed in 79 patients (47%), and according to the most intensive pain localization they were divided into three groups. All the patients were treated with alpha adrenergic blockers and non-steroidal anti-inflammatory drugs, and the treatment of the patients with positive urethral smear also included antibiotherapy. The values of total NIH-CPSI, as well as of its individual components were analyzed after three and six months of treatment. RESULTS AND DISCUSSION: The therapy application had a significant influence on the decrease of total NIH-CPSI--23.3% (p < 0.01), pain symptoms (p < 0.0) and urinary difficulties (p < 0.01), and the point values of quality-of-life score were diminished by 0.7 to 1.9 points depending on the group of those monitored (p < 0.01). CONCLUSION: Our study indicated a significant influence of CPPS on quality-of-life and a necessity of a serious approach to patients and their treatment.

Paraneoplastic bleeding disorder due to isolated hypofibrinogenemia: a case report.

An 80 years old male patient was admitted in our hospital with massive haematomas in the left forearm, chest and abdominal wall accompanied by intense back pain symptoms. Laboratory evaluation showed anemia, mild thrombocytopenia and elevated lactate dehydrogenase and alkaline phosphatase levels and normal concentrations of all the other biochemical parameters. Study of the coagulation status demonstrated prolonged thrombin time (TT), low fibrinogen levels--0.98 g/l while plasminogen, antithrombin III (AT III) and protein C levels were found to be within normal range. Computed tomography scans of the head, chest and abdomen showed an enlarged infiltrative prostate, osteolytic bone lesions in vertebras L5-S1 and a large haematoma of the abdominal wall as the only pathologic findings. Very high levels of the prostate specific antigen indicated the possible existence of a prostate carcinoma with metastases to the vertebral column that resulted in elevated alkaline phosphate and lactate dehydrogenase levels. There were no signs of liver involvement and impaired hepatic synthetic function. Based on the results of the laboratory tests we concluded that the cause of the bleeding disorder in our patient was an acquired hypofibrinogenemia, which is a very rare paraneoplastic phenomenon. The patient was treated with daily transfusions of cryoprecipitate with no long-term improvement. Then the specific anti-tumor therapy (ciproteron acetate) was initiated, and two weeks later, fibrinogen concentration and TT returned to normal values.

[Late methylene blue appearance in urine after local treatment of cutaneous fistula in hip osteomyelitis as a first sign of renal failure].

Methylene blue is a dark green crystal. In medicine it is used as water or alcohol solution. Methaemoglobinemia, hypotension, septic shock are some of many diseases that are treated with methylene blue. In surgery methylene blue is used in diagnostic procedures such as a fistula detection or detection of the parathyroids glands, and for the delineation of certain body tissues during surgery. In patient with normal renal function methylene blue is appearing in urine in a few minutes after intravenous administration. In our patient who was 70-year-old we remarked interesting phenomena after we instillation methylene blue into the fistila channel during local treatment of hip osteomyelitis. Methylene blue appeared in urine two days after local treatment, coloring the urine light green and color elimination time was prolonged in few days. These parameters induced as to suspect in renal failure. That was prowed after urological, laboratory and radiology examination.

Understanding hypertension through genetic manipulation in mice.

With the advances in mouse molecular genetics and physiology during the last decade, the mouse has become the animal model of choice for studying the genetic basis of many diseases. Terms such as "transgenic" and "knockout" have become part of a colloquial language used in most research laboratories that are investigating human diseases. These terms refer to the two most commonly used methods for analyzing the function of a gene in vivo: overexpression (transgenic mouse) and deletion (knockout mouse). Both methods have proved to be extremely useful in establishing the importance of specific genes in genetic disorders, such as hypertension. The choice of genes being investigated in relationship to hypertension was governed by the knowledge of systems regulating vascular and renal physiology. Thus, it is not surprising that most of the focus was given to the renin-angiotensin system (RAS). Apart from the RAS, other systems known to regulate vascular tone and/or electrolyte and fluid homeostasis have also been analyzed using transgenic and knockout approaches. This review briefly summarizes some of the mouse models relevant to renal mechanisms of hypertension and then discusses the future of genetic manipulation in mice for studying the genetics of hypertension.

Appropriate tissue- and cell-specific expression of a single copy human angiotensinogen transgene specifically targeted upstream of the HPRT locus by homologous recombination.

Development of experimental models by genetic manipulation in mice has proven to be very useful in determining the significance of particular genes in the development of or susceptibility to hypertension. Advances in molecular genetics, transgenic mouse technology, and physiological measurements in mice provided an opportunity to go a step further and develop models to analyze the physiological significance of specific gene variants potentially causing hypertension. In this report, we describe the development of a human angiotensinogen transgenic mouse model generated by targeting the human angiotensinogen gene upstream of the mouse HPRT locus by homologous recombination. The main benefit of this transgenic mouse model is that the human angiotensinogen gene is inserted into the mouse genome as a single copy at a predefined locus and in a specific orientation-a process that can be repeated utilizing other variants of this gene. We establish the validity of this approach by showing that the hAGT(hprt) mice have normal tissue- and cell-specific expression of the human angiotensinogen gene and normally produce and process the hAGT protein at physiological levels.

[Magnetic stimulation of the motor cortex in healthy persons]. / Magnetna stimulacija motornog korteksa kod zdravih ispitanika.

In 49 healthy volunteers the motor cortex was stimulated transcranially by the intensive short magnetic field and the responses of the m. abductor digiti minimi (m. ADM) in 20 volunteers were recorded and of the m. tibialis anterior (m. TA) in 29 volunteers in relaxation and in mild contraction. In all volunteers by the electric stimulation of the ulnar nerve in the region of the wrist and the peroneal nerve in the region of the fibular capitulum there have been measured the F wave latency, distal latency of M responses and the conduction time of the peripheral motor neuron has been calculated. The difference between the latency of m. ADM and n. TA responses and the conduction time of the peripheral motor nerve represented the central motor conduction time from the motor cortex to the motor neurons of the anterior horns of the spinal cord (C8 and L4 segments). The normative values of the absolute latencies of the muscle responses and the central motor conduction time in the relaxed and contracted muscle are calculated as well as the normatives of the normal differences in latencies and the central motor conduction time between the left and right side of the same subject.