Evidence against solar influence on nuclear decay constants

The hypothesis that proximity to the Sun causes variation of decay constants at permille level has been tested and disproved. Repeated activity measurements of mono-radionuclide sources were performed over periods from 200 days up to four decades at 14 laboratories across the globe. Residuals from the exponential nuclear decay curves were inspected for annual oscillations. Systematic deviations from a purely exponential decay curve differ from one data set to another and are attributable to instabilities in the instrumentation and measurement conditions. The most stable activity measurements of alpha, beta-minus, electron capture, and beta-plus decaying sources set an upper limit of 0.0006% to 0.008% to the amplitude of annual oscillations in the decay rate. Oscillations in phase with Earth's orbital distance to the Sun could not be observed within a 10^-6 to 10^-5 range of precision. There are also no apparent modulations over periods of weeks or months. Consequently, there is no indication of a natural impediment against sub-permille accuracy in half-life determinations, renormalisation of activity to a distant reference date, application of nuclear dating for archaeology, geo- and cosmochronology, nor in establishing the SI unit becquerel and seeking international equivalence of activity standards.

Diagnostic value of quantitative EUS elastography for malignant pancreatic tumors: relationship with pancreatic fibrosis

PURPOSE

EUS elastography has been used to facilitate the diagnosis of pancreatic cancer, but as yet the interpretation of this procedure has been largely subjective. The present study has been designed to validate a quantitative approach for the analysis of EUS elastography, and to assess its relationship with pancreatic fibrosis.

MATERIALS AND METHODS

86 patients with malignant pancreatic masses and 28 control subjects without any evidence of pancreatic diseases were examined by EUS elastography. EUS video sequences were subjected to a quantitative analysis based on mean hue histogram analysis. Pancreatic fibrosis was determined by quantitative morphometry in tissue specimens from 36 patients.

RESULTS

The mean RGB (red, green, blue) value was significantly higher in the cancer patients compared to the controls (14.0 ± 0.4 vs. 11.5 ± 0.9; p = 0.0085), albeit with significant overlap between the groups. In contrast, a much sharper separation between the groups was obtained based on the individual color values for blue, green and red (p < 0.0001, respectively). By these means, 100 % sensitivity and specificity for the distinction between tumor and normal tissue was obtained for the blue color value, while the red and green color values were less discriminative. The fractional fiber content of the tumors was unrelated to the respective hue histogram color values.

CONCLUSION

Quantitative EUS elastography allows for clear differentiation between malignant pancreatic tumors and normal tissue. Using this approach, we demonstrated that the stiffness of pancreatic tumors is largely independent of their fiber content.

[Cardiopulmonary Exercise Testing (CPET) in severe COPD--a multicentre comparison of two test protocols]

Cardiopulmonary exercise testing (CPET) allows a valid evaluation of cardiopulmonary function capability and the recognition of existing limitations in COPD patients. Whereas the measurement of the different parameters of CPET and the evaluation of the results are standardised, this does not apply to the protocols chosen. The aim of this study was to evaluate whether the results of two different exercise protocols were comparable in an outpatient multicentre setting. Ninety COPD patients stages II-IV according to the Gold classification were examined by means of symptom-limited exercise testing on a bicycle with two different ramp protocols (10 Watts vs. 16 Watts/min) within seven days. The results show that a higher acceleration rate of the load was associated with shorter exercise duration and higher achieved exercise capacity. Gas exchange and ventilatory parameters did not show significant differences on comparing both protocols. In pulmonary practices COPD patients of the Gold stages II-IV can be examined safely and with validity by means of CPET. The application of a ramp protocol with a stepwise increase of 16 Watts/minute can be recommended, particularly as for this regimen standardised normal values are available.

Pancreatic diabetes manifests when beta cell area declines by approximately 65% in humans

AIMS/HYPOTHESIS

Diabetes frequently develops in patients with pancreatic disorders. We aimed to determine the lower threshold of beta cell area for diabetes manifestation as well as the impact of insulin sensitivity on glucose homoeostasis in patients with pancreatic diabetes.

METHODS

Eighty-two patients undergoing pancreatic surgery underwent pre-operative oral glucose challenge. Fractional pancreatic beta cell area was determined, and indices of insulin sensitivity and beta cell function were calculated.

RESULTS

HbA1c and glucose levels were similar in patients with high and intermediate beta cell area, but were significantly higher in those with the lowest beta cell area (p < 0.0001). Insulin secretion was reduced only in patients with the lowest beta cell area (p < 0.001). The relative beta cell deficits at the onset of diabetes and impaired glucose tolerance were 64% and 21%, respectively, based on 2 h glucose levels. Deteriorating insulin sensitivity was associated with a small increase in the incidence of diabetes.

CONCLUSIONS/INTERPRETATION

In conclusion, pancreatic diabetes probably develops after a reduction in beta cell area of ~65%. Post-challenge glucose excursions are much more closely related to pancreatic beta cell area than to fasting glycaemia, thereby underlining the usefulness of the OGTT in patients with pancreatic disorders.

Determinants of glucose control in patients with chronic pancreatitis

AIMS/HYPOTHESIS

Diabetes frequently develops in patients with chronic pancreatitis (CP). Partial pancreatectomy has emerged as a treatment option for such patients. We addressed whether the development of diabetes in CP patients is related to pancreatic beta cell area or clinical variables, and which factors predict the diabetes risk after partial pancreatectomy.

METHODS

Fractional beta cell area was determined in pancreatic tissue samples obtained from 114 CP patients undergoing pancreatic surgery and related to measures of glucose control, as well as clinical and anthropometric data. Seventy-four patients without diabetes at the time of surgery were contacted again 2.5 +/- 1.0 years after partial pancreatectomy in order to obtain information about the post-operative development of diabetes.

RESULTS

In the surgical samples in the whole cohort, pancreatic beta cell area was 0.40 +/- 0.06% in patients with and 0.64 +/- 0.06% in those without previously known diabetes (p = 0.039). There was an inverse non-linear relationship between pancreatic beta cell area and fasting glucose concentrations (r = 0.29) as well as HbA(1c) levels (r = 0.36). Nineteen out of 74 previously normoglycaemic patients (26%) developed diabetes over an average period of 2.5 years of follow-up. Pre-operative fasting glucose levels, HbA(1c) and BMI were identified as predictors of diabetes after partial pancreatectomy. However, pancreatic beta cell area did not differ in those who subsequently developed diabetes (0.66 +/- 0.15%) and those who did not (0.62 +/- 0.08%, p = 0.45).

CONCLUSIONS/INTERPRETATION

Hyperglycaemia in CP patients is associated with reduced beta cell area. However, reduced beta cell area does not predict the development of diabetes, suggesting that other factors are more important determinants of alterations in glucose metabolism in patients with CP.

Expression of beta-defensin 4 is increased in human gastritis

BACKGROUND

Infection with Helicobacter pylori (H. pylori) leads to the initiation of innate immune responses with increased antimicrobial peptide (AMP) expression in the gastric epithelium. This study aimed to determine the expression of the novel peptides beta-defensin 4 (hBD-4) and RNase 7 in infectious and non-infectious gastritis. Furthermore, pattern recognition receptors and mechanisms of regulation were characterized.

MATERIALS AND METHODS

Expression of AMPs was quantified by real-time PCR in biopsies obtained from healthy individuals and patients with infectious and non-infectious gastritis as well as in AGS gastric epithelial cells infected with H. pylori. Distribution of hBD-4 in the gastric mucosa was characterized by in-situ hybridisation and immunohistochemistry. The role of Toll-like receptors (TLRs) 2 and 4 and associated signalling pathways was addressed.

RESULTS

hBD-4 was expressed at low levels in gastric epithelial cells and was significantly upregulated in infectious and non-infectious gastritis. Standard eradication but not acid suppression therapy significantly decreased hBD-4 expression. Cytotoxin associated gene (cag)A positive H. pylori significantly increased the expression of hBD-4 whereas cagA negative organisms, non-viable bacteria or culture supernatants had no significant effect. Overexpression and downregulation of TLRs was not associated with an altered hBD-4 expression. However, blocking experiments revealed an essential role for the p38 mitogen-activated protein kinase. RNase7 was inconsistently expressed in biopsies and not significantly upregulated by H. pylori.

CONCLUSIONS

hBD-4 may play a significant role in H. pylori associated gastritis. Inconsistent expression of RNase 7 does not support a pivotal role for this peptide in response to infection with H. pylori.

Metabolic consequences of a 50% partial pancreatectomy in humans

AIMS/HYPOTHESIS

Partial pancreatectomy is frequently performed in patients with pancreatic tumours or chronic pancreatitis, but little is known about the metabolic impact of this intervention. We examined the effects of approximately 50% partial pancreatectomy on glucose homeostasis and insulin secretion.

METHODS

Fourteen patients with chronic pancreatitis, ten patients with pancreatic carcinoma and 13 patients with benign pancreatic tumours or extra-pancreatic masses (control group) underwent 240 min oral glucose tolerance tests before and after pancreatic tail-resection (n = 12), duodenopancreatectomy (n = 19) or duodenum-preserving pancreatic-head resection (n = 6).

RESULTS

Partial pancreatectomy led to a reduction in post-challenge insulin excursions by 49% in chronic pancreatitis patients, 52% in carcinoma patients and 55% in controls (p < 0.05). Nevertheless, post-challenge glucose concentrations were transiently ameliorated after surgery (p < 0.001). In the control participants, pancreatic-head resection caused a transient reduction of post-challenge glycaemia, whereas pancreatic-tail resection increased both fasting and post-challenge glycaemia (p < 0.05). Insulin sensitivity was highest in chronic pancreatitis patients before surgery (p < 0.01), but remained unchanged by the partial pancreatectomy. High pre-operative body weight and elevated fasting glucose levels were associated with poor glycaemic control after surgery.

CONCLUSIONS/INTERPRETATION

Insulin secretion is diminished after pancreatic-head and -tail resection, but post-challenge glucose concentrations can be ameliorated after pancreatic-head resection. These data highlight the unequal impact of different surgical procedures on glucose control and suggest that obesity and high pre-operative glucose levels should be considered as risk factors for the development of hyperglycaemia after pancreatic surgery.

Activity standardisation of 18F and ionisation chamber calibration for nuclear medicine

Primary activity standardisations were performed on solutions of (18)F using 4pibeta-gamma coincidence counting and liquid scintillation counting (LSC) according to the CIEMAT/NIST method. A beta(+)-emission probability of 96.86% was used for both methods. The various standardised (18)F solutions were measured in ionisation chambers of the Physikalisch-Technische Bundesanstalt (PTB) and compared by determining radionuclide calibration factors. Already in 2001 an (18)F solution had been standardised at the PTB and compared with the results of nine national metrology institutes (NMIs), using the ISOCAL IV secondary radionuclide calibrators of the National Physical Laboratory (NPL) as transfer instruments and a (68)Ge check source solution. These results were linked to the International Reference System (SIR) at the Bureau International des Poids et Mesures (BIPM) by aliquots of solutions sent by the Laboratoire National Henri Becquerel (BNM-LNHB) and the NPL. Further on, in 2005, PTB sent an aliquot of an (18)F solution to the SIR for ionisation chamber measurements. A value of the equivalent activity was determined and included in the key comparison database (KCDB). The recent PTB value of the equivalent activity of the SIR is in good agreement with the key comparison reference value determined from five NMIs. These results confirm that the standardisation of (18)F solutions can be achieved with the accuracy required for use in nuclear medicine and, in particular, for applications in positron emission tomography (PET).

Examination of the diagnostic validity of 'headache attributed to whiplash injury': a controlled, prospective study

Acute and chronic headache attributed to whiplash injury are new diagnostic entities in the International Classification of Headache Disorders, second edition. A main objective of the present study was to assess the validity of these nosologic entities by studying the headache pattern in an inception cohort of 210 rear-end car collision victims and in 210 matched controls. Consecutive drivers involved in rear-end collisions were identified from the daily records of the Traffic Police Department of Kaunas, Lithuania. A standard self-report questionnaire was sent to the drivers between 2 and 7 days after the collision, and their passengers were recruited as well. Headache and neck pain were evaluated within 7 days of the collision, at 2 months and 1 year after the collision. A control group of non-traumatized subjects received questionnaires at the time of the selection and 1 year later. Of the 75 collision victims who developed headache within the first 7 days of the collision, 37 had a clinical picture in accordance with the criteria for acute whiplash headache (i.e., concomitant neck pain) and 38 did not. For acute headache after collision, concomitant neck pain was of no relevance to the headache type or its course. In both these subgroups, migraine and tension-type headache could be diagnosed in similar proportions and the prognosis after 2 months and 1 year was also similar. Preexisting headache was a strong prognostic factor in both groups for both acute and chronic pain. Compared with the non-traumatized control group, the 1-year incidence of new or worsened headache, or of headache improvement, was the same. A likely interpretation of the data is that acute headaches after rear-end car collisions mainly represent episodes of a primary headache precipitated by the stress of the situation. We conclude that the nosologic validity of both acute and chronic whiplash headache is poor as the headaches, in accordance with the criteria lack distinguishing clinical features and have the same prognosis compared with headaches in a control group.

Photon–photon coincidences for activity determination: I-125 and other radionuclides

Theory and experiment of photon-photon coincidence counting with distance variation for activity standardisation of radionuclide solutions are described. The activity of an I-125 solution from an international comparison organised by the BIPM in 2004 was determined. The value obtained agrees with other methods within a limit of 0.2%. The extension of this activity standardisation method to other radionuclides such as Cd-109 with I-125 as a tracer nuclide, In-111, Am-241 and I-124 with a radionuclidic impurity of I-125 is studied. Achieved uncertainties of the activities of Cd-109 and In-111 are of the order of 1.5%. The activity values of sources of Am-241 are determined relative to each other. Am-241 is used for checking the measuring system and as a long-lived reference source. After decay of the order of several I-124 half-lives, sources of I-124 with I-125 are measured to determine the I-125 activity portion.

Standardization and nuclear decay data of 65Zn

Standardization by means of 4pibeta-gamma coincidence counting was applied to calibrate a 65Zn solution within the scope of EUROMET project no. 721. The activity result was combined with gamma-ray spectrometry measurements to investigate the photon emission probabilities. The half-life of 65Zn was measured with improved accuracy by means of 4pi ionization chamber measuring systems that were also used for secondary activity determination. In addition, we tested a new secondary standardization procedure by means of liquid scintillation counting.

Activity standardization and nuclear decay data of 109Cd

The activity of a (109)Cd solution has been accurately determined without using (109)Cd nuclear decay data such as emission probabilities. An ampoule containing this calibrated (109)Cd solution was sent to the Bureau International des Poids et Mesures to include the activity result in the database of the International Reference System (SIR). The emission rate of conversion electrons was measured by means of pressurized proportional counters as well as by a liquid scintillation spectrometer. The combination of the results with the photon emission rate measured with the aid of gamma-ray spectrometers yields the activity concentration. The measurement results were also used to deduce emission probabilities with high accuracy. For the 88 keV transition, a photon emission probability of p(gamma)=0.03663(33) and a total internal conversion coefficient of alpha(t)=26.30(25) were determined.

Severe poisoning with sotalol and verapamil. Recovery after 4 h of normothermic CPR followed by extra corporeal heart lung assist

In acute poisoning with beta-blocking drugs and calcium-channel blockers patients may present with serious symptoms. We present a case of life-threatening sotalol and verapamil intoxication in a 29-year-old female suffering from depression. She was admitted to our hospital a few hours after she had taken 3.6 g verapamil and 4.8 g sotalol. On being found the patient was breathing and had a palpable pulse. On admission the patient experienced a cardiovascular collapse and CPR was started. Echocardiography confirmed cardiac standstill. After 4 h of normothermic CPR, extra corporeal heart lung assist (ECHLA) was established. Vasoactive drugs could be stopped after 2 days with ECHLA, and after 5 days the patient was extubated. The patient experienced several complications (intestinal bleeding, transient nerve paralysis, and renal failure due to rhabdomyolysis) but made a complete recovery and started working 6 months after the poisoning. She was no longer depressed.

A controlled prospective inception cohort study on the post-concussion syndrome outside the medicolegal context

In an earlier historical cohort study on the post-concussion syndrome (PCS) in Lithuania, a country in which there are few confounding factors, the validity of this condition as a disease entity could not be confirmed. In order to register the post-traumatic symptoms, the influence of sociodemographic factors, and the effect of expectation on these symptoms more reliably, we performed a controlled prospective study. Three hundred subjects with concussion were followed up with repeated questionnaires for 1 year. For each study subject, a sex- and age-matched control person with minor non-head injury was identified. These controls received similar questionnaires. Headache both after 3 months and after 1 year did not differ significantly between the head-injured participants and the non-head-injured controls. Several other symptoms attributed to PCS did not differ significantly between the groups after 3 months. After 1 year the vast majority of symptoms did not differ significantly. Exceptions were slightly significant differences concerning memory problems, concentration problems, dizziness and tiredness. These differences were insignificant when analysing symptoms in unmarried and/or people with lower education, separately. No relationship between cognitive dysfunction and the severity of concussion was found. Although the possibility of a mild organic brain injury cannot be completely ruled out, our results cast doubt on the validity of PCS as a useful clinical entity, at least for head injuries with loss of consciousness for <15 min. Sociodemographic factors and expectation seem to influence reporting of symptoms after concussion.

Activity standardization by liquid scintillation counting and half-life measurements of

Radioactive 90Y was standardized by means of 4piBeta liquid scintillation efficiency tracing with a two-phototube counting system. The efficiencies of 90Y and the tracer 3H are related by the CIEMAT/NIST method. The dependence of the calculated efficiency on various shape factors and the importance of accurately measuring the radionuclide impurity of 90Sr are discussed. The half-life of 90Y was measured with improved accuracy by means of a liquid scintillation counting and a 4pi ionization chamber measuring system, and an average value T1/2 = 64.053(20) h was found.

Comparison of ionization chamber efficiencies for activity measurements

The calibration of ionization chamber measuring systems in terms of activity is described. The energy-dependent efficiency curves of three chambers at the Bureau International des Poids et Mesures, the National Physical Laboratory and the Physikalisch-Technische Bundesanstalt are determined and compared using a fitting procedure for the experimental radionuclide efficiencies by the Microsoft (MS) EXCEL Solver program. An estimation of the uncertainty of the efficiency curves and the deviations of experimental and calculated radionuclide efficiencies are given. By this fitting method, discrepancies in the efficiency determination can be detected at a level of about one percent. Systematic deviations entering into the calculations either from emission probabilities per decay or from absolute activity standardization are discussed.

Half-life measurements with ionization chambers—A study of systematic effects and results

Accurate half-lives have been determined at the Physikalisch-Technische Bundesanstalt (PTB) using ionization-chamber measuring systems to assure the quality of radioactivity standards over the period of their use as detector calibrants or other purposes such as nuclear medicine and environmental monitoring. Some long-lived radionuclides have been measured for up to 28 years: 85Kr, 90Sr, 108Agm, 133Ba, 152Eu, 154Eu, and more recently 65Zn, 106Ru, 109Cd and 137Cs; short-lived radionuclides have also been studied such as: 18F, 67Ga, 81Rb, 99Mo, 99Tcm, 103Pd, 111In, 123I, 131I, 153Sm, 169Er, 177Lu, 186Re, 188Re, 201Tl, 222Rn and 224Ra. Relative uncertainties of half-life values of the order of 5 x 10(-4) were obtained. These values are compared to the results of other measurements and evaluations, and the limiting systematic effects are discussed.

Sleep apnoea and chronic headache

The objective of this study was to estimate prevalence of headache and body pain among patients referred for suspected sleep apnoea syndrome compared with the occurrence in a large population-based study (the Nord-Trøndelag Health Study). Between 1995 and 1998, ambulatory polysomnography was successfully performed in 421 consecutive patients, 324 of whom completed a questionnaire about sleep-related habits, headache and body pain. Headache and neck pain were more likely among patients admitted for polysomnography compared with the general population (n = 41 340). In the multivariate analyses, this association was mainly restricted to those with frequent complaints (> or =7 days per month). Chronic headache (headache > or = 15 days per month) was seven times more common among individuals with and without confirmed obstructive sleep apnoea syndrome than in the general population. There was no linear dose-response relationship between headache and neck pain and severity of apnoea or oxygen desaturation. Thus, hypoxia per se is less likely to explain the high headache prevalence among patients admitted for polysomnography.

The effects of acetylsalicylic acid on proliferation, apoptosis, and invasion of cyclooxygenase-2 negative colon cancer cells

BACKGROUND

Acetylsalicylic acid (ASA, aspirin), the most common nonsteroidal anti-inflammatory drug (NSAID), has been shown to have a protective effect against the incidence and mortality of colorectal cancer. However, the mechanism of its anticancer function remains unclear. The aim of this study was to determine the effects of acetylsalicylic acid on proliferation, apoptosis, and invasion in human cyclooxygenase-2 (COX-2) negative colorectal cancer cell lines.

MATERIALS AND METHODS

After treatment with various concentrations of ASA, cell proliferation was measured in the human colon cancer cell line SW480. Apoptotic cells were identified by transmission electron microscopy, acridine orange staining, and flow cytometry. The invasive potential of SW480 cells was detected using an in vitro invasion assay. The production of carcinoembryonic antigen was measured by microparticle enzyme immunoassay. Expression of Bcl2, Bax, CD44v6, and nm23 were evaluated by immunocytochemistry.

RESULTS

ASA significantly inhibited the proliferation of SW480 cells and stimulated apoptosis. Production of carcinoembryonic antigen and the invasive potential of SW480 cells were also inhibited by ASA. After treatment with ASA, down-regulation of Bcl2 and CD44v6 expression and up-regulation of nm23 expression were observed in SW480 cells. No obvious effect of ASA was found on Bax expression.

CONCLUSION

Our findings reveal that ASA inhibits the proliferation and promotes apoptosis in the human colon cancer cell line SW480. Down-regulation of Bcl2 expression might represent a potential mechanism by which ASA induces apoptosis in this COX-2 negative colon cancer cell line. Our results also suggest that ASA decreases the invasive potential of these colon cancer cells. Decreased CEA content and CD44v6 expression and elevated nm23 expression may contribute to the effect of ASA on invasive potential of SW480 colon cancer cells.

A controlled historical cohort study on the post-concussion syndrome

In Lithuania, expectation of chronic symptoms after minor head injury is less than in western countries and possibilities for monetary compensation are minimal. Therefore, an opportunity exists to study the post-concussion syndrome (PCS) without several confounding factors present in western societies. We sent questionnaires about symptoms attributed to PCS to 200 subjects who had a concussion with loss of consciousness between 35 and 22 months before the study. For each study subject, a sex- and age-matched control person with minor non-head injury was identified. These controls received similar questionnaires. All the responding post-concussion patients stated that they had had acute headache after the trauma but this headache had disappeared in 96% of cases within 1 month. Headache and dizziness at the time of the questioning were not significantly more prevalent in the patients with concussion than in the controls, and there was no significant difference concerning subjective cognitive dysfunction. Scores of visual analogue scales of symptoms attributed to PCS showed no significant differences except for depression, alcohol intolerance and worry about brain injury, which were more frequent in the concussion group. No specific effect of the head injury was detected when various definitions and different constellations of core symptoms of PCS were used. These findings question the validity of the PCS as a useful clinical entity.

Prevalence and risk factors of hepatitis C virus infection in haemodialysis patients: a multicentre study in 2796 patients

BACKGROUND

Hepatitis C virus (HCV) infection is a significant problem in the management of haemodialysis patients. A high prevalence of HCV infection in haemodialysis patients has been reported. Risk factors such as the number of blood transfusions or duration on haemodialysis have been identified.

AIM

To determine the prevalence of HCV by antibody testing and HCV-RNA determination by polymerase chain reaction (PCR) in haemodialysis patients. Furthermore, liver function tests were performed and epidemiological data were obtained to determine risk factors for HCV in this cohort of patients.

RESULTS

A total of 2796 patients from 43 dialysis centres were enrolled. The overall prevalence of HCV (HCV antibody and/or HCV-RNA positivity) was 7.0% (195 patients). Antibody positivity occurred in 171 patients (6.1%). Viraemia was detectable in 111 patients (4.0%). Twenty four of 111 HCV RNA positive patients (21.6%) were negative for HCV antibodies. Thus 0.8% of the entire study population was HCV positive but could not be diagnosed by routine HCV antibody testing. Major risk factors identified by a standard questionnaire in 1717 of 2796 patients were the number of blood transfusions individuals had received and duration of dialysis, the latter including patients who received no blood transfusions. Sequencing of the 5'untranslated region of the genome showed a dominant genotype 1 (77.6%) within the cohort. Further reverse transcription-PCR of the NS5b and core region were performed to document phylogenetic analysis. Comparing nucleic acid sequences detected by PCR, no homogeneity was found and thus nosocomial transmission was excluded.

CONCLUSIONS

HCV is common in German haemodialysis patients but screening for HCV antibodies alone does not exclude infection with HCV.

Results obtained in the metrological certification of a commercially available radionuclide calibrator

The paper presents the results obtained at IFIN-HH during a metrological certification of the commercially available radionuclide calibrator, the CURIEMENTOR2. Its performance was tested for the radionuclides: 57Co, 99mTc, 131I and 137Cs. The calibration factors determined by the manufacturer and those obtained at IFIN-HH differed by less than 3.5%. New calibration factors were determined for 60Co and 188Re, which have, until now, not been distributed by the manufacturer to the users. Furthermore, the linearity of instrument response and the dependence of measuring geometry were checked and found in accordance with the international accepted standards and legal requirements.

Fitting methods for constructing energy-dependent efficiency curves and their application to ionization chamber measurements

An ionization chamber without and with an iron liner (absorber) was calibrated by a set of radionuclide activity standards of the Physikalisch-Technische Bundesanstalt (PTB). The ionization chamber is used as a secondary standard measuring system for activity at the Slovak Institute of Metrology (SMU). Energy-dependent photon-efficiency curves were established for the ionization chamber in defined measurement geometry without and with the liner, and radionuclide efficiencies were calculated. Programmed calculation with an analytical efficiency function and a nonlinear regression algorithm of Microsoft (MS) Excel for fitting was used. Efficiencies from bremsstrahlung of pure beta-particle emitters were calibrated achieving a 10% accuracy level. Such efficiency components are added to obtain the total radionuclide efficiency of photon emitters after beta decay. The method yields differences of experimental and calculated radionuclide efficiencies for most of the photon-emitting radionuclides in the order of a few percent.

Cellular expression of CCK-A and CCK-B/gastrin receptors in human gastric mucosa

Gastrin stimulates gastric acid secretion in various species, but the role of the structurally related CCK for the peripheral regulation of acid secretion in humans remains controversial. Moreover, species differences in CCK receptor function and expression have been reported. We therefore sought to identify the cellular targets of CCK and gastrin within the human gastric mucosa in situ. Gastric biopsies were collected from 15 patients without gastric disease. Expression of CCK receptor subtypes was detected in individual cells of the gastric mucosa by reverse transcription (RT)-PCR in situ, immunohistochemistry and confocal laser scanning microscopy, using antisera against the CCK-A or CCK-B/gastrin receptor subtype. Both CCK-A and CCK-B receptors were detected in antral and oxyntic mucosa at the mRNA and protein level. In fundic mucosa, CCK-A receptor mRNA and protein mapped to D cells (37.4+/-7.7). Besides, individual chief cells, mucous neck cells and parietal cells (12.3+/-4.7%) expressed CCK-A receptors. CCK-B/gastrin receptor mRNA and protein were detected in parietal cells (57.4+/-11.1%) and in neuroendocrine cells (33.2+/-4.4%) expressing chromogranin A. Furthermore, epithelial cells within the neck of the gastric gland were found to express the CCK-B/gastrin receptor. We conclude that (i) identification of CCK-A receptors on somatostatin producing D cells in humans provide the anatomical basis for a receptor-mediated mode of action of CCK on somatostatin release and (ii) detection of either CCK receptor subtype in the putative stem cell compartment implies a role of CCK in the maintenance of tissue homeostasis in human gastric mucosa.

[Intravenous thrombolytic treatment of acute basilar artery occlusion]

BACKGROUND

Acute stroke with basilar artery occlusion is a serious condition with high mortality and severe disability.

MATERIAL AND METHODS

We describe three patients with acute artery basilar occlusion treated with thrombolytic agent given intravenously.

RESULTS

One patient demonstrated early and considerable clinical improvement parallel to thrombolytic therapy started two and a half hour after ictus, but suffered a new occlusion and died in a "locked-in syndrome". One patient demonstrated moderate clinical improvement after less than six hours and survived with disability. One patient demonstrated no clinical improvement with thrombolytic therapy started six hours after ictus and later died of an injured brainstem. No patients had serious bleeding.

INTERPRETATION

Intravenous, systemic thrombolytic treatment may have a beneficial effect in acute basilar occlusion.

Identification of CCK-B/gastrin receptor splice variants in human peripheral blood mononuclear cells

There is increasing evidence for a direct interaction of the enteric nervous and immune system. Receptors for neuropeptides such as VIP, somatostatin, and substance P have been characterised in human immuno-haematopoietic cells but little is known about the functional significance and expression of receptors for cholecystokinin (CCK) on cells of the immune system. There are only few studies that describe the expression of CCK receptors on human leukaemia-derived cell lines but the receptor structure and function in normal leukocytes have not been clearly established. We therefore sought to determine CCK receptor expression, structure, and function in nontransformed human peripheral blood mononuclear cells.Full-length cDNA clones encoding the human CCK-A and CCK-B/gastrin receptor are expressed in peripheral blood mononuclear cells from healthy volunteers without haematopoietic malignancy. In addition to wild-type CCK-B/gastrin receptor cDNAs, we isolated a splice variant with an in frame insertion of 69 amino acids within its putative third intracellular receptor loop. Dideoxy sequence analysis revealed that the cDNA of this splice variant comprises exons 1-4 but retains intron 4 (207 bp) in the absence of mutations within the splice donor sites. Transient expression of this splice variant in COS-7 cells reveals wild-type affinity for CCK-8, Gastrin-17, and antagonist L-365,260. Affinity for glycine-extended gastrin-17 was not increased when compared to the wild-type CCK-B/gastrin receptor. In vitro, gastrin decreased 3H-thymidine labelling in phytohaemagglutinin-pretreated mononuclear cells at a half-maximally effective concentration of 1.5 nM. We also isolated a cDNA encoding another splice variant of the CCK-B/gastrin receptor with a 158 bp deletion of the entire exon 4 sequence. We conclude that wild-type transcripts of both CCK receptor subtypes and splice variants of the CCK-B/gastrin receptor are expressed in nontransformed human mononuclear cells and that gastrin exhibits antiproliferative effects.

Standardisation and decay data of 177Lu and 188Re

The activity values of 177Lu and 188Re standard sources were measured using the 4pibeta-gamma-coincidence method and by liquid scintillation counting. The X- and gamma-ray emission probabilities per disintegration were determined by means of photon spectrometry with calibrated Ge and Si(Li) detectors and using the pertinent activity values. The half-lives were measured with ionization chambers, yielding T(1/2)(177Lu) = 6.646(5) d and T(1/2)(188Re) = 0.70848(9) d.

The late whiplash syndrome: a biopsychosocial approach

Physicians and other therapists continue to grapple in daily practice with the controversies of the late whiplash syndrome. For decades much of the debate and the approach to this controversial syndrome has centred on the natural history of and progression to chronic pain after acute whiplash injury. Recognising that there is recent epidemiological data that defines the natural history of the acute whiplash injury outside of many of the confounding factors occurring in many western countries, and the lack of evidence for a "chronic whiplash injury", this article will thus introduce the biopsychosocial model, its elements, its advantages over the traditional model, and the practical application of this model. The biopsychosocial model recognises physical and psychological sources of somatic symptoms, but fundamentally recognises that the late whiplash syndrome is not the result of a "chronic injury".

Prophylactic treatment of migraine with angiotensin converting enzyme inhibitor (lisinopril): randomised, placebo controlled, crossover study

OBJECTIVE

To determine the efficacy of an angiotensin converting enzyme inhibitor in the prophylaxis of migraine.

DESIGN

Double blind, placebo controlled, crossover study.

SETTING

Neurological outpatient clinic.

PARTICIPANTS

Sixty patients aged 19-59 years with migraine with two to six episodes a month.

INTERVENTIONS

Treatment period of 12 weeks with one 10 mg lisinopril tablet once daily for one week then two 10 mg lisinopril tablets once daily for 11 weeks, followed by a two week wash out period. Second treatment period of one placebo tablet once daily for one week and then two placebo tablets for 11 weeks. Thirty participants followed this schedule, and 30 received placebo followed by lisinopril.

MAIN OUTCOME MEASURES

Primary end points: number of hours with headache, number of days with headache, number of days with migraine. Secondary end points: headache severity index, use of drugs for symptomatic relief, quality of life and number of days taken as sick leave, acceptability of treatment.

RESULTS

In the 47 participants with complete data, hours with headache, days with headache, days with migraine, and headache severity index were significantly reduced by 20% (95% confidence interval 5% to 36%), 17% (5% to 30%), 21% (9% to 34%), and 20% (3% to 37%), respectively, with lisinopril compared with placebo. Days with migraine were reduced by at least 50% in 14 participants for active treatment versus placebo and 17 patients for active treatment versus run-in period. Days with migraine were fewer by at least 50% in 14 participants for active treatment versus placebo. Intention to treat analysis of data from 55 patients supported the differences in favour of lisinopril for the primary end points.

CONCLUSION

The angiotensin converting enzyme inhibitor, lisinopril, has a clinically important prophylactic effect in migraine.

[Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy]

BACKGROUND

Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (Nasu-Hakola syndrome) (PLO-SL) is an unusual cause of early dementia in which the decline in cognitive function is associated with multiple bone cysts, in particular in hands and feet. About 165 cases of this autosomal recessive hereditary disease have been reported worldwide, mostly from Finland and Japan.

MATERIAL AND METHODS

In this article, case histories of PLO-SL are presented of two brothers who were born to consanguineous parents on an island outside the western coast of Norway. They are the 3rd and 4th patients in Norway described with this disorder.

RESULTS

One of the brothers was diagnosed retrospectively and the diagnosis was not made in the other even when he had fractures without entirely adequate trauma.

INTERPRETATION

It is suspected that the disease is underdiagnosed. For this reason, all patients with polycystic lesions in the skeleton should be evaluated for their mental state and all patients with an etiologically unclear dementia before the age of 50 should be investigated with x-rays of hands and/or feet.

Prevalence of temporomandibular disorders associated with whiplash injury in Lithuania

OBJECTIVE

The purpose of this study was to ascertain the prevalence of symptoms of temporomandibular disorders in whiplash victims in Lithuania and compare it with the prevalence in otherwise healthy control subjects.

STUDY DESIGN

In a controlled historical cohort study in Lithuania, we asked each of 210 victims of vehicular rear-end collisions (at 14-27 months after the accident) to report the presence and frequency of a number of temporomandibular disorder symptoms. The results were compared with those for an age-matched and gender-matched control group, sampled randomly from the local population.

RESULTS

In the accident group, 2.4% of subjects (4/165) reported jaw pain for 1 day or more per month; this compared with 3.3% of the controls (6/180). One (0.6%) of the accident victims and 2 (1.1%) of the controls had daily jaw pain. In both groups there was a low prevalence of jaw sounds, pain in or near the ear(s), jaw locking, tinnitus, and facial pain.

CONCLUSIONS

Unlike whiplash claimants in many Western societies, Lithuanian accident victims do not appear to report the chronic symptoms of temporomandibular disorders despite their acute whiplash injuries.

The best approach to the problem of whiplash? One ticket to Lithuania, please

The Quebec Task Force (QTF) on Whiplash Associated Disorders (WAD)--1995--sent a clear message that we need to re-evaluate the basis for our treatment strategies, and in particular place more emphasis on research to better define these strategies. Judging by many of the clinical strategies currently in use, the Task Force recommendations seem to have been largely ignored three years later. A further compelling reason to re-evaluate our current practices at this time is the finding of much more rapid recovery rates in some cultures, even with little or no therapy. This commentary is a frank consideration of the therapeutic community's responsibility to not only help solve the dilemma of whiplash, but also avoid contributing to the problem. We thus explore a new biopsychosocial model of whiplash, considering the effects of symptom expectation, amplification, and attribution in chronic pain reporting. Based on that model we propose a treatment strategy, and conclude that such strategies provide the only viable approach to this medicolegal and social dilemma.

Pain after whiplash: a prospective controlled inception cohort study

OBJECTIVES

In Lithuania, there is little awareness of the notion that chronic symptoms may result from rear end collisions via the so-called whiplash injury. After most such collisions no contact with the health service is established. An opportunity therefore exists to study post-traumatic pain without the confounding factors present in western societies.

METHODS

In a prospective, controlled inception cohort study, 210 victims of a rear end collision were consecutively identified from the daily records of the Kaunas traffic police. Neck pain and headache were evaluated by mailed questionnaires shortly after the accident, after 2 months, and after 1 year. As controls, 210 sex and age matched subjects were randomly taken from the population register of the same geographical area and evaluated for the same symptoms immediately after their identification and after 1 year.

RESULTS

Initial pain was reported by 47% of accident victims; 10% had neck pain alone, 18% had neck pain together with headache, and 19% had headache alone. The median duration of the initial neck pain was 3 days and maximal duration 17 days. The median duration of headache was 4.5 hours and the maximum duration was 20 days. After 1 year, there were no significant differences between the accident victims and the control group concerning frequency and intensity of these symptoms.

CONCLUSIONS

In a country were there is no preconceived notion of chronic pain arising from rear end collisions, and thus no fear of long term disability, and usually no involvement of the therapeutic community, insurance companies, or litigation, symptoms after an acute whiplash injury are self limiting, brief, and do not seem to evolve to the so-called late whiplash syndrome.

Headache after whiplash: a historical cohort study outside the medico-legal context

Headache is frequently reported as a chronic complaint after whiplash traumas. Criteria have been presented, but it has not been validated whether any specific headache type emerges after a trauma with whiplash mechanism. In a questionnaire-based historical cohort design, 202 adult Lithuanian individuals were interviewed 1-3 years after experiencing a rear-end car collision. The questionnaire was designed so that a diagnosis of migraine and tension-type headache in accordance with the International Headache Society criteria could be made. "Possible cervicogenic headache" was diagnosed according to Sjaastad et al.'s minimal criteria. The diagnostic panorama in those with traumas was compared with that of an age- and sex-matched control group. The introductory questions did not reveal differences in headache frequencies between the traumatized and control groups (p = 0.60). The prevalence of migraine and tension-type headache (both episodic and chronic) was also similar. A higher frequency of possible cervicogenic headache was observed in the traumatized group (10 vs 5), but the difference was not statistically significant (p = 0.28). Sixteen patients in the accident group had headache > 15 days per month, 11 of the 16 had similar complaints before the trauma, while 5 had worsened headache as compared to (the recollected headache) before the trauma. None of the patients with possible cervicogenic headache reported increased headache after the accident. Accordingly, the present results obtained outside the medico-legal context do not confirm that a specific headache pattern emerges 1-3 years after a rear-end car collision.