Electron beam ion sources for use in second generation synchrotrons for medical particle therapy

Cyclotrons and first generation synchrotrons are the commonly applied accelerators in medical particle therapy nowadays. Next generation accelerators such as Rapid Cycling Medical Synchrotrons (RCMS), direct drive accelerators, or dielectric wall accelerators have the potential to improve the existing accelerator techniques in this field. Innovative accelerator concepts for medical particle therapy can benefit from ion sources which meet their special requirements. In the present paper we report on measurements with a superconducting Electron Beam Ion Source, the Dresden EBIS-SC, under the aspect of application in combination with RCMS as a well proven technology. The measurements indicate that this ion source can offer significant advantages for medical particle therapy. We show that a superconducting EBIS can deliver ion pulses of medically relevant ions such as protons, C(4 +) and C(6 +) ions with intensities and frequencies required for RCMS [S. Peggs and T. Satogata, "A survey of Hadron therapy accelerator technology," in Proceedings of PAC07, BNL-79826- 2008-CP, Albuquerque, New Mexico, USA, 2007; A. Garonna, U. Amaldi et al., "Cyclinac medical accelerators using pulsed C(6 +)/H2(+) ion sources," in Proceedings of EBIST 2010, Stockholm, Sweden, July 2010]. Ion extraction spectra as well as individual ion pulses have been measured. For example, we report on the generation of proton pulses with up to 3 × 10(9) protons per pulse and with frequencies of up to 1000 Hz at electron beam currents of 600 mA.

UV filters for hair protection

Synopsis Hair damage, caused by sunlight, and the possibility to protect hair against sunlight by means of cosmetic formulations was studied. For this, five UV-filters were tested: benzophenone-3 (UV-A/UV-B); benzophenone-4 (UV-A/UV-B); phenylbenzimidazole sulfonic acid (UV-B); butylmethoxydibenzoylmethane (UV-A); octyl dimethyl PABA (UV-B). The stability of the UV-filters was tested as pure substances as well as in two cosmetic formulations: a setting lotion and a shine spray. The degree of decolouration and stress strain behaviour were determined. The benzophenones had the best protection ability both on colour and on morphology. Stability data and UV-spectra are discussed.

Production of low-Z ions in the Dresden superconducting electron ion beam source for medical particle therapy

We report on experiments with a new superconducting electron beam ion source (EBIS-SC), the Dresden EBIS-SC, with the objective to meet the main requirements for their application in particle-therapy facilities. Synchrotrons as well as innovative accelerator concepts, such as high-gradient linacs which are driven by a large-current cyclotron (CYCLINACS) and direct drive RF linear accelerators may benefit from the advantages of EBISs in regard to their functional principle. First experimental studies of the production of low-Z ions such as H(+), H(2)(+), H(3)(+), C(4+), and C(6+) are presented. Particular attention is paid to the ion output, i.e., the number of ions per pulse and per second, respectively. Important beam parameters in this context are, among others, ion pulse shaping, pulse repetition rates, beam emittance, and ion energy spread.

Optical control of coherent interactions between electron spins in InGaAs quantum dots

Coherent interactions between spins in quantum dots are a key requirement for quantum gates. We have performed pump-probe experiments in which pulsed lasers emitting at different photon energies manipulate two distinct subsets of electron spins within an inhomogeneous InGaAs quantum dot ensemble. The spin dynamics are monitored through their precession about an external magnetic field. These measurements demonstrate spin precession phase shifts and modulations of the magnitude of one subset of oriented spins after optical orientation of the second subset. The observations are consistent with results from a model using a Heisenberg-like interaction with μeV strength.

Short time ion pulse extraction from the Dresden electron beam ion trap

We present measurements of the extraction of short time pulses of highly charged ions (4 keV, Ar(16+)) from the Dresden electron beam ion trap. Thereby the dependence of the extractable ionic charge on the extraction regime was investigated. The ion extraction time was varied between 20 ns and 1 micros. Furthermore the production of carbon ions and the influence of the extraction regime on the pulse widths was investigated to obtain information about the suitability of the Dresden EBIS-A in synchrotron based particle therapy facilities.

Diagnosis-prescribing surveys in 2000, 2002 and 2005 in Swedish general practice: consultations, diagnosis, diagnostics and treatment choices

The aim of this study is to present diagnostic patterns, diagnostics used and antibiotic treatment in relation to guidelines in 3 repeated diagnosis-prescription studies conducted simultaneously in general practice in 5 Swedish counties, during 1 week in November 2000, 2002 and 2005. General practitioners (GPs) at the participating health centres were asked to complete a form for all patients with symptoms of an infectious disease. During the studied periods a total of 15,371 consultations was registered. Consultations with GPs diagnosed as respiratory tract infection (RTI), especially consultations for sore throat, decreased considerably between y 2000 and 2005. The percentage of patients allocated an RTI diagnosis and prescribed an antibiotic declined significantly from 54% to 49% and the decline was most pronounced among children. Penicillin V remained the dominant antibiotic prescribed throughout the study periods. For lower urinary tract infections there was a significant change in choice of prescribed antibiotics with an increase for pivmecillinam and nitrofurantoin and a decrease for trimethoprim, in accordance with recommendations. The results indicate a quite close adherence to current guidelines, with changes in the pattern of consultations as well as in the management of infectious diseases in general practice in Sweden.

A novel form of autosomal recessive hereditary spastic paraplegia caused by a new SPG7 mutation

BACKGROUND

Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous neurodegenerative disorder characterized by progressive spastic paraparesis of the lower limbs.

OBJECTIVE

To identify the genotype and characterize the phenotype in a family with a novel form of complicated autosomal recessive hereditary spastic paraparesis (ARHSP).

METHODS

Six subjects of a Turkish family were examined by clinical evaluation, detailed neuropsychological testing, neurophysiologic studies, MRI, diffusion tensor imaging (DTI), and mutation analysis of SPG7 gene.

RESULTS

Three individuals were affected by a juvenile-onset form of complicated ARHSP due to the missense mutation c.2075G>C in exon 15 of the SPG7 gene in the homozygous state, substituting serine with threonine at codon 692. As additional clinical features, cerebellar syndrome, supranuclear palsy, and cognitive impairment, particularly disturbance of attention and executive functions, were found. MRI showed cerebellar atrophy and mild frontal cerebral atrophy. DTI revealed bilateral disturbance of white matter integrity in corticospinal tracts, frontal lobes, and the midbrain.

CONCLUSIONS

The new SPG7 gene mutation leads to a novel complicated autosomal recessive hereditary spastic paraparesis phenotype that widens the spectrum of different brain systems that are optionally affected in hereditary spastic paraplegia (HSP). In this novel phenotype, spastic paraparesis is related to cerebral damage of corticospinal tracts. Impairment of attention and executive functions is due to white matter loss in frontal lobes. Furthermore, supranuclear palsy is caused by white matter damage in the midbrain. This multisystem affection, which was detected by the use of diffusion tensor imaging, may reflect a mitochondrial dysfunction that contributes to the underlying pathogenesis of SPG7-HSP.

Early-onset ALS with long-term survival associated with spastin gene mutation

The authors report a 73-year-old patient with a natural history of early-onset ALS for 49 years presenting with limb and bulbar amyotrophy and a pyramidal syndrome. Analysis of the locus SPG4 identified a heterozygous duplication mutation (c.304_309dupGCCTCG) within exon 1 of the spastin gene. We propose that sequence alterations of spastin may comprise a genetic risk factor in a greater spectrum of motor neuron disorders including clinical variants of ALS.

The use of CRP tests in patients with respiratory tract infections in primary care in Sweden can be questioned

A diagnosis-antibiotic prescribing study was performed in 5 counties in Sweden during 1 week in November in 2000 and 2002 respectively. As a part of the study, the use and results of C-reactive protein (CRP) tests in relation to duration of symptoms and antibiotic prescribing in 6778 patients assigned a diagnosis of respiratory tract infections were analysed. In almost half (42%) of the patients, a CRP test was performed. The majority of CRP tests (69%) were performed in patients assigned diagnosis upper respiratory tract infection, where the test is not recommended. Overall, there was a minor decrease in antibiotic prescribing when CRP was used (41%), in comparison to 44% of the patients where no CRP was performed (p < 0.01). Patients assigned diagnoses implying a bacterial aetiology were prescribed antibiotics irrespective of result of CRP or length of symptoms before consultation. For patients assigned viral diagnoses, antibiotic prescribing increased with increasing duration of symptoms and increasing value of CRP. The use of CRP decreased antibiotic prescribing in patients assigned to viral diagnoses and with longstanding symptoms (p < 0.001). However, 59% of the patients assigned viral diagnoses with CRP > or = 25 received antibiotics, which seems to indicate a misinterpretation of CRP and a non-optimal use of antibiotics.

Upper respiratory tract infections in general practice: diagnosis, antibiotic prescribing, duration of symptoms and use of diagnostic tests

A diagnosis/antibiotic prescribing study was performed in 5 counties in Sweden for 1 week in November 2000. As part of this study, the characteristics and clinical management of patients with upper respiratory tract infections (n = 2899) in primary care were analyzed. Almost half of the patients were aged < 15 y and one-fifth of the patients consulted out of hours. Of all patients seeking primary care for upper respiratory tract infections, 56.0% were prescribed an antibiotic. Almost all patients who were given the diagnoses streptococcal tonsillitis, acute otitis media or acute sinusitis were prescribed antibiotics, compared to 10% of patients with common cold or acute pharyngitis. The most frequently prescribed antibiotic was penicillin V (79.2%) and this was even more pronounced out of hours, when the diagnoses otitis media and streptococcal tonsillitis were more frequently used. In patients with common cold and acute pharyngitis, the percentage who received antibiotics increased with increasing length of symptoms and increasing CRP levels. In patients with acute pharyngitis or streptococcal tonsillitis, antibiotics were prescribed less frequently provided streptococcal tests were performed. The management of patients with upper respiratory tract infections in general practice seems to be in good agreement with current Swedish guidelines. However, the study indicates some areas for improvement. The diagnosis of acute sinusitis seems to have been overestimated and used only to justify antibiotic treatment.

[STRAMA questionnaire on general practitioners' knowledge concerning antibiotics and resistance. Lack of time impedes exchange of information]

The Uppsala county regional group of the Swedish Strategic Programme for the Rational Use of Antimicrobial Agents and Surveillance of Resistance (STRAMA) sent a questionnaire to all the general practitioners in the county concerning their knowledge of antibiotics and bacterial resistance. The questionnaire also asked which sources were used for information on these topics, and inquired as to their views concerning the services provided by the local clinical microbiological laboratory. A third part of the questionnaire contained descriptions of three patients with infectious diseases, and each general practitioner was asked to indicate appropriate diagnostic tests and/or antibiotic treatment. The questionnaire was completed by 70% (100/145). The general awareness of which antibiotics to use for empirical treatment of urinary tract infection was good. Awareness of antibiotic resistance in S. pyogenes, H. influenzae, S. pneumoniae and MRSA was moderately good (59-80%). About 60% thought it was difficult to find information concerning resistance and use of antibiotics. Lack of time was the main reason for not being able to seek such information actively. The regional STRAMA-group believes that this kind of survey followed by reporting back of results with informative comments on the topics concerned is a useful model for education.

Less difference between office and ambulatory blood pressure in women than in men both before and during antihypertensive treatment

In 199 subjects (56% women) with a diastolic blood pressure (BP) of 95-115 mmHg, 5 mg of either amlodipine or felodipine extended release (ER) was given for 4 weeks following 4 weeks of placebo-treatment. BP was measured by conventional clinic BP technique and by 24-h ambulatory BP monitoring (Spacelab 90202/90207). Men and women had identical clinic BP at baseline and it was lowered equally much by 4 weeks of treatment (men: 158/101 and 147/93, women: 159/102 and 149/93 mmHg, respectively). However, ambulatory BP was higher in women than in men both before and after treatment (men: 145/91 and 134/85, women: 149/95 and 140/89 mmHg, respectively, p < 0.05 for both comparisons). The difference between clinic BP and daytime ambulatory BP was higher in men than in women (systolic men: 8.1 +/- 14, women: 3.7 +/- 15 mmHg, respectively, p = 0.04; diastolic men: 5.5 +/- 8.0, women: 2.1 +/- 8.3 mmHg, p = 0.004). The correlation between the treatment effect measured by ambulatory and clinic BP was poor (systolic r = 0.26, p < 0.0001; diastolic r = 0.17, p = 0.03) and was unaffected by exclusion of subjects with normal ambulatory BP. The poor correlation between treatment effects measured as clinic and ambulatory BP is intriguing, and suggests that using ambulatory BP instead of clinic BP for monitoring the treatment of hypertension could affect the clinical outcome.

Effect of amlodipine versus felodipine extended release on 24-hour ambulatory blood pressure in hypertension

Amlodipine and felodipine are calcium antagonists of the dihydropyridine type. The elimination half-life of amlodipine is longer than that of felodipine. To study whether the different elimination rates of the drugs were reflected in different duration of blood pressure (BP) control, we compared amlodipine and felodipine extended release (ER) by both conventional clinic BP 24 h after drug intake and 24 h ambulatory BP monitoring (ABPM), with special reference to nighttime and morning blood pressure. Two hundred and sixteen patients with primary hypertension (supine diastolic BP, 95 to 115 mm Hg) were randomized to receive amlodipine or felodipine ER in a multicenter study. The starting dose of both drugs was 5 mg. If the target clinic diastolic BP (90 mm Hg) had not been achieved after 4 weeks the dose was increased to 10 mg. Twenty-four-hour ABPM was performed with the subjects taking placebo medication before randomization and after 4 and 8 weeks undergoing active treatment. Significantly more patients responded after 4 weeks of treatment with amlodipine (50%) as compared with felodipine (33%) (P = .013). ABPM during daytime (07:00 to 23:00) was similar during both treatments, but nighttime systolic (P = .026) and diastolic (P = .019) BP was more effectively reduced by amlodipine than by felodipine. After 8 weeks 82% achieved the target pressure with amlodipine and 69% with felodipine (P = .036 for the difference). Amlodipine seems to be more effective than felodipine when the drugs are compared in the same dose, with regard to the effect on clinic BP 24 h after dosing and to ambulatory BP during the night. The longer elimination half-life of amlodipine as compared to felodipine is the probable reason for this finding.

Recurrence rate of streptococcal pharyngitis related to hygienic measures

OBJECTIVE

To test the hypothesis that treatment failures of streptococcal pharyngotonsillitis may be caused by reinfection by the patients' own streptococci remaining on a toothbrush or in the bedclothes.

DESIGN

To elucidate the role of streptococcal contamination of the environment, hygienic measures regarding change of toothbrush and bed linen and washing of toys were given to half of the patients/families. Throat specimens were taken from all the patients before treatment with phenoxymethylpenicillin for 5 days, and the patients were followed-up for 1 month. At a home visit after 6-10 days, throat specimens were taken from the patients and all permanent residents of the home. Environmental samples were taken from pillowcases, floors, toothbrushes, dummies, and toys.

SETTING

Six health care centres.

SUBJECTS

114 patients of all ages suffering from group A streptococcal pharyngotonsillitis, and 289 family members.

MEASUREMENTS AND MAIN RESULTS

54 patients/families received hygiene instructions. The total number of recurrences was 40 (35%). There was no difference in treatment failure rate between patients/families that had taken or not taken hygienic measures.

CONCLUSIONS

Hygienic measures have no decisive influence on the risk of recurrence of streptococcal pharyngotonsillitis.

Acid-catalyzed plasmenylcholine hydrolysis and its effect on bilayer permeability: a quantitative study

This laboratory has previously shown (Anderson, V.C. and Thompson, D.H. (1992) Biochim. Biophys. Acta 1109, 33-42; Thompson, D.H., Gerasimov, O.V., Wheeler, J.J., Rui, Y. and Anderson, V.C. (1996) Biochim. Biophys. Acta 1279, 25-34), that plasmenylcholine (1-alk-1'-enyl-2-palmitoyl-sn-glycero-3-phosphocholine; PlsPamCho) liposomes release hydrophilic contents upon photooxidation or acid-catalyzed hydrolysis. We now report the kinetics and chemical mechanism of the acid-catalyzed reaction and its effect on calcein leakage rates. Hydrolysis of the plasmenylcholine vinyl ether linkage generates fatty aldehydes and 1-hydroxy-2-palmitoyl-sn-glycero-3-phosphocholine (lysolipid); HPLC and 1H-NMR experiments establish that the former is readily air-oxidized to fatty acids, while the latter undergoes rapid acid-catalyzed rearrangement to 1-palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine. Lysolipid formation obeys first order kinetics, yielding observed pseudo-first order rate constants that are pH-dependent. Bimolecular hydrolysis rate constants, k(bi), have also been determined. Calcein release rates from plasmenylcholine liposomes are strongly dependent on both the dihydrocholesterol (DHC) content and the extent of PlsPamCho hydrolysis within the bilayer. DHC-free plasmenylcholine liposomes (38 degrees C, pH 2.5) require < 5% PlsPamCho hydrolysis to effect > 50% calcein release within 10 min. The presence of > or = 25 mol% DHC, however, greatly reduces the observed calcein release rate; nearly 30% PlsPamCho hydrolysis is required to effect 50% calcein release over a 70-min period in 6:4 PlsPamCho/DHC liposomes. Bacteriochlorophyll a-sensitized photooxidation of plasmenylcholine liposomes also produces fatty aldehyde and another intermediate, tentatively described as 1-formyl-2-palmitoyl-sn-glycero-3-phosphocholine, that hydrolyzes to form the 1-hydroxy lysolipid. These results have important implications for the quantitative description of lysolipid effects on membrane permeability and on the design of triggerable liposomes for drug delivery.

The role of household contacts in the transmission of group A streptococci

The intrafamilial spread and recurrence of group A beta-haemolytic streptococci (GAS) infections was investigated. The evaluation was based on 114 patients and their families treated with penicillin for 5 days and followed for 1 month. GAS of the same T-type as that of the isolate from the index case were found in other family members in 33% of the families. Genetic finger-printing using RFLP was performed on 33 of the isolates. The mothers dominated among the index cases, 40 patients experienced recurrences, 27 of them were clinical 28 recurrences occurred within 10 days after the end of treatment. Of 20 T-typed patients with early clinical treatment failures, infected family members were detected in 16 families (p < 0.001). In 19% of the patients GAS could be isolated from the nose. These patients had more ill family members than did other patients. An extensive intrafamilial streptococcal spread was found. Most recurrences of GAS pharyngotonsillitis after penicillin treatment are probably due to "ping pong" infection from family members.

Independent association between fasting plasma insulin and ambulatory blood pressure in 50-year-old women

The aim of the present study was to investigate correlations between fasting insulin and ambulatory blood pressure in healthy 50-year-old women. Sixty-five women without anti-hypertensive medication were investigated at a Primary Health Care Centre in Enköping, Sweden. Fasting plasma insulin, office blood pressure and heart rate were measured as well as ambulatory blood pressure and heart rate (Spacelab 90202). Log-transformed insulin correlated with all blood pressure recordings (r = 0.3-0.5; p < 0.05) but only with night-time heart rate (r = 0.3; p < 0.05). In multiple regression analyses log-insulin still correlated with night-time systolic blood pressure and heart rate, but not with the other blood pressure variables, after elimination of the influence of body mass index. We conclude that fasting plasma insulin shows an obesity-independent correlation with night-time systolic blood pressure and heart rate in healthy women, possible indicators of a "basic" sympathetic nervous outflow in muscle tissue during sleep.

Local and systemic immune response in Helicobacter pylori-associated chronic gastritis before and after treatment

Ten patients with Helicobacter pylori-associated chronic gastritis were given combination therapy for 6 weeks with a bismuth subnitrate-containing compound and bacampicillin. The eradication rate was 40% 6 weeks after the end of treatment. Two patients remained H. pylori-negative at long-term follow-up after 6 and 17 months; that is, H. pylori was only eradicated in 20% of the patients after long-term observation. By dot blot and immunoblotting both urease and an urease-associated heat shock protein (HSP62) were found to be specific and constant immunodominant H. pylori antigens. The immunohistologic pattern showed induced expression of HLA-DR and HSP62, but not of ICAM-1, in all but two biopsy specimens of gastric epithelial cells. This study suggests i) that long-term observation is important when evaluating the efficacy of anti-H. pylori therapy; ii) that the immune defense mechanisms in the gastric mucosa differ from those in inflammatory conditions affecting other organs, where ICAM-1 and HLA-DR seem to be governed by a common regulator; and iii) that the immunopathologic effects of H. pylori may be caused by autologous and/or bacterial HSPs, which act as triggering factors in the development and persistence of the chronic inflammation in the gastric mucosa.

Postural effects on diastolic blood pressure are differently recorded by a non-invasive ambulatory blood pressure monitor and a standard auscultatory device

The aim of this study was to determine the influence of change of posture on blood pressure as recorded with an automatic ambulatory blood pressure monitor and a standard auscultatory device. The blood pressure difference between sitting and supine and between standing and supine posture was 1.1/3.9 and 6.5/6.3 mmHg, respectively, for the monitor recordings, and 0.7/6.7 and 7.9/14.8 mmHg, respectively, for the standard recordings. All differences were significant, except the systolic blood pressure difference between sitting and supine posture. There were no significant differences in systolic blood pressure between monitor and standard recordings in any posture. The corresponding differences in diastolic blood pressure were significant in sitting (-4.6 mmHg) and standing postures (-10.3 mmHg), but not in supine posture (-1.8 mmHg). It is concluded that a change of posture contributes to blood pressure variability, and agreement between diastolic blood pressure in supine subjects, as recorded by an ambulatory monitor and a standard device, does not necessarily mean agreement in standing (or sitting) subjects.

Short-term variation in blood pressure determines the accuracy of simultaneous and sequential recordings in the validation of blood pressure measuring devices

Short-term intradevice variation of BP was determined by means of consecutive BP recordings. The intradevice variation was mainly the result of spontaneous, random variation in BP and was the same for invasive, automated oscillometric and auscultatory random zero meter recordings. We show that the accuracy of simultaneous and sequential recordings, performed according to the recommendation of the British Hypertension Society's protocol for the evaluation of automated BP devices, can be calculated by means of statistical analysis if the intradevice variation of the BP is known. We found, for both sequential and for simultaneous recordings, a close agreement between the expected and the observed proportion of differences that fall within certain specified limits and that it is more favourable for a test device to be evaluated by sequential than by simultaneous recordings.

Cardiovascular risk factors in treated hypertensives--a nation-wide, cross-sectional study in Sweden

Hypertensive patients still face a considerable risk of cardiovascular disease in spite of drug treatment in many studies. This may partly be explained by metabolic disturbances, both primarily linked to hypertension but also secondarily influenced by anti-hypertensive drugs themselves. In order to evaluate residual cardiovascular risk factors we investigated 1915 treated hypertensives (912 males, 1003 females) attending 128 health centres from all parts of Sweden. Mean blood pressure was 148/91 mmHg for males and 151/90 for females, but a substantial proportion of all patients were not well controlled, having a diastolic blood pressures > or = 100 mmHg (17% males, 12% females). Total cholesterol and HDL-cholesterol were 6.03 and 1.25 mmol l-1 for males, and 6.40 and 1.50 for females. The corresponding figures for serum triglycerides were 2.03 and 1.72 mmol l-1, respectively. In all, 38% of the hypertensives had hypercholesterolaemia (> or = 6.5 mmol l-1) and 27% hypertriglyceridaemia (> or = 2.3 mmol l-1). The lipid/lipoprotein findings may also be influenced by the various anti-hypertensive drugs used in Sweden. The prevalence of smoking and diabetes mellitus were 25% and 11% for men, and for women 24% and 9%. In conclusion, Swedish hypertensives show evidence of significant residual cardiovascular risk factors in spite of treatment. This may be of importance for future relative and absolute cardiovascular risk. It is time to re-evaluate the effectiveness of our management and care of hypertensive patients.

Reference values for 24-hour non-invasive ambulatory blood pressure: a population study of men aged fifty

All 50-year-old men (N = 126) living in a defined neighbourhood were invited to undergo 24-hour ambulatory, non-invasive blood pressure (BP) monitoring. The participation rate was 90%. Seven per cent of the subjects were taking antihypertensive drugs and 19% had a current diagnosis of hypertension or had been so diagnosed sometime previously. The 5th, 50th, and 95th percentiles of the subjects' ambulatory BP are presented. On average, daytime, night-time, and 24-hour ambulatory BP were 135/86, 114/68, 128/80 mmHg, respectively, and the average casual BP was 137/86 mmHg. The ambulatory BP in the present study was higher than in previous reference studies. No attempt was made to select the stratified subjects according to casual BP or any other medical or social variable. This and a high participation rate probably account for the difference in ambulatory BP vis-à-vis those found in other reference studies.

Traditional risk-factor profile fails to explain striking geographical differences in IHD mortality among middle-aged men. The project "myocardial infarction in mid-Sweden"

An east-west gradient in cardiovascular mortality has been reported from the region of mid-Sweden. Postal questionnaire studies found that the risk factor distributions among middle-aged men were similar in areas with striking differences in cardiovascular mortality. In this study, 120 randomly selected 50-year-old men in two high mortality communities in the west and 120 men from two low mortality communities in the east were invited to a health survey in which serum lipids and other risk factors were analysed. Total serum cholesterol, LDL-cholesterol, HDL-cholesterol, and triglyceride levels were similar. Among fatty acids, stearic acid was high and arachidonic acid was low in the high mortality area. The levels of other traditional risk factors were the same. After taking these differences into account, the mortality differences remain large.

Effect on sleep--but not on blood pressure--of nocturnal non-invasive blood pressure monitoring

OBJECTIVE

Nocturnal non-invasive ambulatory blood pressure monitoring inevitably causes an undesirable external stimulus due to the cuff pressure and, for some monitors, disturbing compressor sound. The objective of the present study was to determine whether non-invasive automated blood pressure monitoring during sleep provokes arousal and changes in blood pressure and/or heart rate.

DESIGN

Sleep response and blood pressure reaction during and immediately after blood pressure monitoring were studied by means of simultaneous electroencephalography and blood pressure recordings.

METHODS

Blood pressure and electroencephalogram were recorded simultaneously in 24 subjects (10 hypertensive, 14 normotensive). Blood pressure was registered with a non-invasive automatic blood pressure monitor every 20 min. Inflation and deflation of the cuff were registered on one of the electroencephalogram channels by means of a small pressure meter attached to the cuff. For each subject, blood pressure during uninterrupted sleep was compared with that during arousal provoked by the recordings.

RESULTS

Blood pressure recording caused an arousal in 67% of the recordings. During 33% of the recordings, sleep continued. Neither systolic nor diastolic blood pressure differed significantly for recordings during 'uninterrupted sleep' when compared with arousal. Heart rate was significantly faster during arousal than during uninterrupted sleep. Analysed separately, hypertensive subjects showed an overall blood pressure response close to that of normotensive subjects. There was a significant trend towards lower blood pressure, parallel with deeper sleep.

CONCLUSIONS

The results of this study show that non-invasive ambulatory blood pressure monitoring during sleep accurately records basal blood pressure and can distinguish blood pressure during superficial sleep from blood pressure during deep sleep. Sleep is often disturbed by blood pressure monitoring but, irrespective of whether recording provokes arousal, monitored blood pressure is the same.

Two cases of neonatal pneumococcal septicemia

Pneumococci (Streptococcus pneumoniae) infrequently cause neonatal septicemia. An increased number of cases have been reported in recent years, but no increase in the relative incidence among neonatal infections has been noted. Two recent cases that occurred within a short period of time are described. They were found to exhibit most clinical characteristics, previously described, of Group B Streptococci (GBS) septicemia with an early onset, but appear to have a graver prognosis.

Neonatal septicemia caused by pneumococci

Pneumococci (Streptococcus pneumoniae) infrequently cause neonatal septicemia. An increased number of cases have been reported in recent years, but no increase in the relative incidence among neonatal infections has been noted. On the basis of two cases of our own and a review of 40 recently published case reports, the clinical characteristics of pneumococcal septicemia are described and the pathogenesis is discussed. The presenting clinical picture in early-onset pneumococcal septicemia is dominated by respiratory distress, frequently accompanied by leukopenia, and is indistinguishable from that seen in septicemia caused by Group B Streptococci (GBS). The onset is preceded by prelabor rupture of the fetal membranes in almost half of the instances. The mortality is 50%, twice the figure given in recent GBS reports.

Streptococcal throat infection: calculation of test standards and a comparison between an antigen detection test and culture

The standard minimum sensitivity (94%) and minimum specificity (89%) of a group A streptococcus (GAS) test were calculated, assuming that no more than 10% false positive and no more than 2% false negative test results should be allowed. The clinical judgement of the need for immediate antibiotic treatment in tonsillitis/pharyngitis was an unreliable indicator of a GAS aetiology, 20-29% of the results being false positive and 2-10% false negative. The rapid antigen detection test Tandem Icon Strep A was not sensitive enough to be used as a single test, though it was specific enough. The sensitivity of culture almost reached the standard demand. Two combinations of rapid test and culture (sequence testing) were superior to the rapid test, but were not significantly better than culture.

The role of a commercial latex agglutination test in the diagnosis of group B streptococcal infection in neonates

An open prospective multicenter study was conducted in order to evaluate the Wellcogen Strep B latex agglutination test in the diagnosis of group B streptococcal (GBS) infections in neonates. Twenty-three (5.9%) of 391 urine specimens and 5 (1.2%) of 404 sera assayed were positive. The results of the urine tests corresponded to a sensitivity of 0.78 for bacteremic, 0.50 for non-bacteremic and 0.53 for all GBS associated (bacteremic, non-bacteremic and suspected) infections. After 20-25-fold concentration of urine specimens the sensitivity increased to 1.0 for bacteremic, 0.67 for non-bacteremic and 0.78 for all GBS associated infections. The specificity of the test was high (0.93 for concentrated urines), and the predictive value of a positive test (Pvpos) was 0.68. A positive latex test was highly predictive of positive surface cultures for GBS (Pv pos = 0.83 after concentration).

Inoculation of barrier-born pigs with Helicobacter pylori: a useful animal model for gastritis type B

At the age of 8 weeks, 15 barrier-born pigs, specific pathogen free, were inoculated intragastrically with suspensions of 10(7) to 10(10) CFU of Helicobacter pylori after pretreatment with omeprazole. The pigs were observed for up to 12 weeks, endoscopic biopsy specimens were taken, and serum samples were drawn. H. pylori was identified by routine culturing and by staining with an H. pylori-specific monoclonal antibody on cryostat sections of gastric biopsy specimens. In 11 of 15 inoculated pigs, H. pylori was detected throughout the observation period. In these infected pigs, there was an antibody response to H. pylori, as determined in serum by an enzyme immunoassay. Furthermore, the development of superficial, focal gastritis with infiltrates of mononuclear class II antigen-expressing lymphocytes was observed immunohistologically. H. pylori was never detected and an antibody response to H. pylori was not observed in two control pigs. The development of gastritis and the systemic antibody response to H. pylori support the usefulness of this animal model for studies of H. pylori-related human diseases.

Antibody response to Staphylococcus saprophyticus in urinary tract infection

The serological response towards Staphylococcus saprophyticus in young women with symptomatic urinary tract infection was measured with an enzyme-linked immunosorbent assay (ELISA) and a direct agglutination (DA) test. In both assays a marked antibody response was found in 2 of 3 patients with acute pyelonephritis caused by S. saprophyticus. Patients with acute cystitis due to S. saprophyticus or Escherichia coli showed antibody titers comparable to those of healthy controls.

Change in posture during sleep causes errors in non-invasive automatic blood pressure recordings

When measured with automatic non-invasive monitors blood pressure is seen to fluctuate during sleep. The recorded blood pressure is influenced by the vertical distance between the heart level (zero reference) and the level of the brachial artery at the point of compression by the inflated cuff. In 20 randomly selected men, blood pressure was measured every 20 min during the night. The difference between consecutive recordings was 7.6 mmHg +/- 5.7/5.0 (s.d.), range 0-23/0-20 mmHg. The maximum blood pressure difference was 19 +/- 6.8/15 +/- 6.0, range 7-32/6-26 mmHg. These results were compared with the difference in blood pressure recorded on the left arm in 20 volunteers changing posture between four standardized recumbent postures. The posture change caused an average blood pressure difference of 9 +/- 6.1/9 +/- 6.5 mmHg, range 0-28/0-30 mmHg. The maximum blood pressure difference was 15 +/- 5.1/12 +/- 5.5 mmHg, range 5-27/(-)2-23 mmHg recorded between lying supine and lying on the right side. The similarity between differences and the variation in blood pressure during the recumbent posture indicates that changes in posture cause most of the night-time blood pressure variation recorded with non-invasive devices.

Colonization with potentially pathogenic respiratory tract bacteria. A household study

A group of 235 persons (180 adults and 55 children 0-15 years old) recorded symptoms of upper respiratory tract infection daily during two three-month periods (autumn 1986 and spring 1987). Samples for culture were taken from the nasopharynx and throat once during each period. Fifteen per cent of asymptomatic subjects harboured respiratory pathogens in the nasopharynx, as did 28% of those subjects with minor respiratory tract infections and 46% of those with more severe respiratory tract infections. Of children up to seven years of age, 58% were colonized with potential respiratory pathogens, which is important to keep in mind when evaluating culture reports from young children. Adults living with young children were colonized significantly more often than other adults. Branhamella catarrhalis was the most common pathogen.

Association of Campylobacter pylori with induced expression of class II transplantation antigens on gastric epithelial cells

Campylobacter pylori was identified with immunoperoxidase staining and a mouse monoclonal antibody directed against C. pylori in gastric biopsy specimens from 24 patients with gastritis. C. pylori was not found in gastric biopsy specimens from six subjects with histologically normal mucosa. The monoclonal antibody, which was reactive with a surface protein of approximately 20 kilodaltons, was found to be specific for C. pylori, and the immunoperoxidase staining proved to be more sensitive and rapid than culture in detecting the organism. In the tissue specimens where C. pylori was detected with the monoclonal antibody, there was a strong expression of class II transplantation antigens on the epithelial cells and an increased number of T lymphocytes. These findings indicate that C. pylori may initiate local immune responses.

Bacteriological and serological aspects of group A streptococcal pharyngotonsillitis caused by group A streptococci

Several bacteriological and serological variables were studied in connection with a clinical treatment trial in 212 patients with group A streptococcal pharyngotonsillitis. Anaerobic incubation was not superior to incubation in 5% CO2 in air for the detection of group A streptococci. Saliva cultures were inferior to conventional throat cultures in detecting group A streptococci. No strains from patients with recurrences were found to be tolerant to penicillin. In several patients (all asymptomatic), group C and G streptococci were found in follow-up cultures. Group A streptococci serology was more often positive after two months than after one month, also in patients without recurrence.

Throat carrier rates of beta-hemolytic streptococci among healthy adults and children

In order to investigate the carrier rate of beta-hemolytic streptococci throat cultures were obtained every third month from 382 asymptomatic adults and schoolchildren during a 2-year period, altogether 2226 samples. In addition, 300 asymptomatic 4-year-olds were sampled once. The carrier rate of beta-hemolytic streptococci was 19.4%; group A streptococci alone 5.0%. There was no season-dependent variation. In the 3 age groups the carrier rates of group A streptococci were 0.8%, 5.9%, and 11.3%, respectively, with the highest rate among the 4-year-olds. Some of the individuals that were sampled repeatedly seemed to be pharyngeal carriers of group A streptococci, while others never became carriers. Group A streptococci were found significantly more often among 4-year-olds not attending day-care centres compared to those attending such institutions. For group C and G streptococci the influence of age on carrier rates was not similar to that found for group A streptococci. Throat carriership of beta-hemolytic streptococci does not result in clinical infections.

Five versus ten days treatment of group A streptococcal pharyngotonsillitis: a randomized controlled clinical trial with phenoxymethylpenicillin and cefadroxil

216 patients aged greater than or equal to 7 years with febrile group A streptococcal pharyngotonsillitis were randomly assigned to 3 treatment groups receiving either phenoxymethylpenicillin for 5 days followed by placebo for 5 days, phenoxymethylpenicillin for 10 days, or cefadroxil for 10 days. 209 patients completed treatment, 70 subjects in each phenoxymethylpenicillin group and 69 in the cefadroxil group. Within 1 week after completion of the antibiotic treatment significantly more recurrences with the same T-type as the initial streptococcal strain occurred in the 5-day treatment group (27%) as compared with the two 10-day groups (6% and 3%, respectively). The cumulative rate of recurrences (irrespective of T-type) within 2 months from the start of therapy was 55% among patients treated with phenoxymethylpenicillin for 5 days, 24% among those treated for 10 days with this drug and 19% among patients receiving cefadroxil. Obviously, one important factor to avoid recurrence of group A streptococcal pharyngotonsillitis is the length of antibiotic treatment and, in our opinion, it is not advisable to change the current recommendation of 10 days treatment.

Age related variations of serum concentrations of normally occurring IgG antibodies to Clostridium perfringens

In studies using indirect immunofluorescence IgG antibodies to Clostridium perfringens were found in sera from healthy adults. Sera from 236 healthy children were examined. The normally occurring IgG antibodies to C perfringens were found to have an age related variation. Preliminary data suggest that they are not correlated to C perfringens alpha toxin. The antigen(s) against which the antibodies are directed is/are probably part of the cell wall, but its/their exact nature is not known.