Dimorphism in cryptophytes-The case of Teleaulax amphioxeia/Plagioselmis prolonga and its ecological implications

Growing evidence suggests that sexual reproduction might be common in unicellular organisms, but observations are sparse. Limited knowledge of sexual reproduction constrains understanding of protist ecology. Although Teleaulax amphioxeia and Plagioselmis prolonga are common marine cryptophytes worldwide, and are also important plastid donors for some kleptoplastic ciliates and dinoflagellates, the ecology and development of these protists are poorly known. We demonstrate that P. prolonga is the haploid form of the diploid T. amphioxeia and describe the seasonal dynamics of these two life stages. The diploid T. amphioxeia dominates during periods of high dissolved inorganic nitrogen (DIN) and low irradiance, temperature, and grazing (winter and early spring), whereas the haploid P. prolonga becomes more abundant during the summer, when DIN is low and irradiance, temperature, and grazing are high. Dimorphic sexual life cycles might explain the success of this species by fostering high genetic diversity and enabling endurance in adverse conditions.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).

Development of a multiperspective optical measuring system for investigating decaying switching arcs at the nozzle exit of circuit breakers

High-voltage gas circuit breakers, which play an important role in the operation and protection of the power grid, function by drawing an arc between two contacts and then extinguishing it by cooling it using a transonic gas flow. Improving the design of circuit breakers requires an understanding of the physical processes in the interruption of the arc, particularly during the zero crossing of the alternating current (the point in time when the arc can be interrupted). Most diagnostic techniques currently available focus on measurement of current, voltage, and gas pressure at defined locations. However, these integral properties do not give sufficient insight into the arc physics. To understand the current interruption process, spatially resolved information about the density, temperature, and conductivity of the arc and surrounding gas flow is needed. Owing to the three-dimensional, unstable nature of the arc in a circuit breaker, especially near current zero, a spatially resolved, tomographic diagnostic technique is required that is capable of freezing the rapid, transient behavior and that is insensitive to the vibrations and electromagnetic interference inherent in the interruption of short-circuit current arcs. Here a new measurement system, based on background-oriented schlieren (BOS) imaging, is presented and assessed. BOS imaging using four beams consisting of white light sources, a background pattern, imaging optics, and a camera permits measurement of the line-of-sight integrated refractive index. Tomographic reconstruction is used to determine the three-dimensional, spatially resolved index of refraction distribution that in turn is used to calculate the density. The quantitative accuracy of a single beam of the BOS setup is verified by using a calibration lens with a known focal length. The ability of the tomographic reconstruction to detect asymmetric features of the arc and surrounding gas flow is assessed semiquantitatively using a nozzle that generates two gas jets, as described in [Exp. Fluids43, 241 (2007)EXFLDU0723-486410.1007/s00348-007-0331-1]. Experiments using a simple model of a circuit breaker, which provides optical access to an ∼1  kA arc that burns between two contacts and is blown through a nozzle system by synthetic air from a high pressure reservoir, are also described. The density in the decaying arc and surrounding gas flow is reconstructed, and the limitations of the technique, which are related to the temporal and spatial resolution, are addressed.

Making metal surfaces strong, resistant, and multifunctional by nanoscale-sculpturing

Surfaces are the crucial and limiting factor in nearly all metal applications, especially when technologically relevant alloys are employed. Insufficient surface properties on the nano- and microscale of metals determine, e.g. metal-polymer composite stability, implant biocompatibility, or corrosion resistance. Conventional surface preparation is just like an arbitrary cut through the metal body optimized for bulk behavior so that such surfaces contain various element mixtures and complex microstructures in which grains and lattice planes vary in their chemical stability from weak to strong. In contrast, the here described novel nanoscale-surface sculpturing based on semiconductor etching knowledge turns surfaces of everyday metals into their most stable configuration, but leaves the bulk properties unaffected. Thus, nanoscale-sculpturing ensures stronger, reliable joints to nearly all materials, reduces corrosion vastly, and generates a multitude of multifunctional surface properties not limited to those shown below.

Stage-specific direct health care costs in patients with cutaneous malignant melanoma

BACKGROUND

Clinical stage at diagnosis is a strong prognostic factor for death in cutaneous malignant melanoma (CMM), with worse prognosis at higher stages. However, few studies have investigated how direct health care cost per patient varies with clinical stage.

OBJECTIVE

The aim of this study was to determine the stage-specific direct health care costs for CMM patients compared to the health care costs in the general population in the County of Östergötland, Sweden.

METHODS

Cutaneous malignant melanoma patients in the County of Östergötland diagnosed 2005-2012 were identified from the Swedish cancer registry. Information on clinical stage was collected from the Swedish Melanoma Register (SMR) and cost data from the Cost per Patient database (CPP) for 1075 CMM patients in Östergötland. CPP contains costs associated with all health care contacts per patient including inpatient, outpatient and primary care. The CMM-related costs were defined as the difference in mean health care costs between CMM patients and general population.

RESULTS

The first year after CMM diagnosis, the average health care costs for CMM patients were 2.8 times higher than in the general population. The health care cost ratio varied from 2.0 (stage I) to 10.1 (stage IV) and the CMM-related costs per patient-year varied from €2 670 (stage I) to €29 291 (stage IV). The mean health care costs decreased over time but remained significantly higher than in the general population for all clinical stages. During the first year after diagnosis, patients in clinical stage III-IV (7% of CMM patients) accounted for 27% of the total CMM-related health care costs.

CONCLUSIONS

The direct health care costs for CMM patients were significantly higher than in the general population independent of clinical stage. CMM patients diagnosed in clinical stage III-IV were associated with particularly high costs and the health care system may save resources by finding CMM patients in earlier stages.

Trends in cutaneous malignant melanoma in Sweden 1997-2011: thinner tumours and improved survival among men

BACKGROUND

Both patient survival and the proportion of patients diagnosed with thin cutaneous malignant melanoma (CMM) have been steadily rising in Sweden as in most Western countries, although the rate of improvement in survival appears to have declined in Sweden at the end of the last millennium.

OBJECTIVES

To analyse the most recent trends in the distribution of tumour thickness (T category) as well as CMM-specific survival in Swedish patients diagnosed during 1997-2011.

METHODS

This nationwide population-based study included 30,590 patients registered in the Swedish Melanoma Register (SMR) and diagnosed with a first primary invasive CMM during 1997-2011. The patients were followed through 2012 in the national Cause of Death Register.

RESULTS

Logistic and Cox regression analyses adjusting for age at diagnosis, tumour site and healthcare region were carried out. The odds ratio for being diagnosed with thicker tumours was significantly reduced (P < 0·001) and the CMM-specific survival significantly improved in men diagnosed during 2007-2011 compared with men diagnosed during 1997-2001 (hazard ratio = 0·81; 95% confidence interval 0·72-0·91; P < 0·001), while the corresponding differences for women were not significant. Women were diagnosed with significantly thicker tumours during 2002-2006 and a tendency towards decreased survival was observed compared with those diagnosed earlier (during 1997-2001) and later (during 2007-2011).

CONCLUSIONS

In Sweden, the CMMs of men are detected earlier over time and this seems to be followed by an improved CMM-specific survival for men. Women are still diagnosed with considerably thinner tumours and they experience a better survival than men.

AEG-1 expression is an independent prognostic factor in rectal cancer patients with preoperative radiotherapy: a study in a Swedish clinical trial

Background:

Preoperative radiotherapy (RT) is widely used to downstage rectal tumours, but the rate of recurrence varies significantly. Therefore, new biomarkers are needed for better treatment and prognosis. It has been shown that astrocyte elevated gene-1 (AEG-1) is a key mediator of migration, invasion, and treatment resistance. Our aim was to analyse the AEG-1 expression in relation to RT in rectal cancer patients and to test its radiosensitising properties.

Methods:

The AEG-1 expression was examined by immunohistochemistry in 158 patients from the Swedish clinical trial of RT. Furthermore, we inhibited the AEG-1 expression by siRNA in five colon cancer cell lines and measured the survival after irradiation by colony-forming assay.

Results:

The AEG-1 expression was increased in the primary tumours compared with the normal mucosa independently of the RT (P<0.01). High AEG-1 expression in the primary tumour of the patients treated with RT correlated independently with higher risk of distant recurrence (P=0.009) and worse disease-free survival (P=0.007). Downregulation of AEG-1 revealed a decreased survival after radiation in radioresistant colon cancer cell lines.

Conclusions:

The AEG-1 expression was independently related to distant recurrence and disease-free survival in rectal cancer patients with RT and could therefore be a marker to discriminate patients for distant relapse.

Abstract P6-07-12: Akt2 expression is associated with good long-term prognosis in estrogen receptor positive breast cancer

Introduction: Akt is a signaling modulator for many cellular processes, including metabolism, cell proliferation, cell survival and cell growth. Three isoforms of Akt have been identified, but only a few studies have concerned the isoform-specific roles in the prognosis of breast cancer patients. The aim of this study was to investigate the prognostic value of Akt1 and Akt2 in estrogen receptor positive (ER+) and estrogen receptor negative (ER−) breast cancer with long-term follow-up.

Material and Methods: The expression of Akt in tumor tissue was analyzed with immunohistochemistry in a cohort of 272 postmenopausal patients with stage II breast cancer. Hazard ratios and 95% confidence intervals were estimated using the Cox's proportional hazards model.

Results: The risk of distant recurrence was reduced for patients with ER+ tumors expressing Akt2 compared to patients with no Akt2 expression (HR = 0.49, 95% CI 0.29–0.82, p = 0.007). When adjusting for important clinical tumor characteristics and treatment, Akt2 was still an independent prognostic factor (HR = 0.38, 95% CI 0.21–0.68, p = 0.001) and the association remained long-term. After more than five years since diagnosis the risk reduction was 57% for patients with Akt2 positive tumors. The prognostic value of Akt2 increased with higher estrogen receptor levels from no effect among patients with ER− tumors to 68% risk reduction for the group with high ER-levels (P for trend= 0.042). Akt1 showed no significant prognostic information.

Magnetizing a complex plasma without a magnetic field

We propose and demonstrate a concept that mimics the magnetization of the heavy dust particles in a complex plasma while leaving the properties of the light species practically unaffected. It makes use of the frictional coupling between a complex plasma and the neutral gas, which allows us to transfer angular momentum from a rotating gas column to a well-controlled rotation of the dust cloud. This induces a Coriolis force that acts exactly as the Lorentz force in a magnetic field. Experimental normal mode measurements for a small dust cluster with four particles show excellent agreement with theoretical predictions for a magnetized plasma.

Availability of insulin pump therapy in clinical practice

AIM

To examine the availability of insulin pump therapy in patients with Type 1 diabetes.

METHODS

Patients using insulin pumps among a cohort of 7224 patients with Type 1 diabetes were studied.

RESULTS

In logistic regression, used to evaluate variables not changing over time among the total cohort, use of insulin pumps varied by outpatient clinic (P<0.001) and sex (P<0.001). Cox regression analysis in 5854 patients with detailed patient data prior to use of an insulin pump showed higher HbA(1c) (P<0.0001), lower creatinine (P=0.002), high and low insulin doses (P<0.0001), younger age (P<0.0001) and female sex (P<0.0001) to be associated with use of an insulin pump. Women were 1.5-fold more likely to start using an insulin pump (hazard ratio 1.52, 95% confidence interval 1.29-1.79) and patients in the 20- to 30-years age range were more than twice as likely to begin use of an insulin pump than patients aged 40-50 years (hazard ratio 8.63, 95% confidence interval 5.91-12.59 and hazard ratio 3.98, 95% confidence interval 2.80-5.64, respectively). A 10-μmol/l higher level of creatinine was associated with a hazard ratio of 0.56 (95% confidence interval 0.39-0.81) of starting use of an insulin pump.

CONCLUSIONS

At 10 hospital outpatient clinics in Sweden, use of insulin pumps therapy varied by clinic. A higher proportion of women began using insulin pumps. Younger patients and patients with fewer complications were also more likely to start using an insulin pump. Further research is needed to confirm these findings in other geographical regions and to understand whether the availability of insulin pumps today is optimized.

Premature birth and low birthweight are associated with a lower rate of reproduction in adulthood: a Swedish population-based registry study

BACKGROUND

The aim of this study was to investigate if individuals born with sub-optimal birth characteristics have reduced probability of reproducing in adulthood.

METHODS

Using population-based registries, the authors included 522 216 males and 494 692 females born between 1973 and 1983 and examined their reproductive status as of 2006. Outcome measure was the hazard ratio (HR) of reproducing. Adjustments were made for socio-economic factors.

RESULTS

Males and females born very premature displayed a reduced probability of reproducing [HR = 0.78, 95% confidence interval (CI): 0.70-0.86 for males; HR = 0.81, CI: 0.75-0.88 for females]. Likewise for very low birthweight (HR = 0.83, CI: 0.71-0.95 for males; HR = 0.80, 95% CI: 0.72-0.89 for females). Individuals born large for gestational age (LGA) displayed no significant changes. Males born small for gestational age (SGA) had a 9% lower reproductive rate (CI: 0.89-0.94) and that reduction increased as the individuals aged. Women born SGA tended to start reproducing at an earlier age.

CONCLUSION

The results suggest that being born with low birthweight, premature or SGA (for males) is associated with a reduced probability of reproducing as an adult. LGA shows no statistically significant relationship with future reproduction.

Comparative SEM and Cathodoluminescence Microanalysis of Porous GaP Structures

Electron microscopy and cathodoluminescence (CL) microanalysis were used for a comparative study of porous layers fabricated by electrochemical etching of n-GaP substrates in a sulfuric acid solution. Both the CL and morphology of porous layers were found to depend upon the anodic current density. At high current density (100 mA/cm2) anodization leads to the formation of so-called current-line oriented pores and an increase in the CL intensity. We observed self-induced voltage oscillations giving rise to a synchronous modulation of the diameter of pores and CL intensity. When the current density decreased to values as low as 1 mA/cm2 the pores began to grow along <111> crystallographic directions and the CL intensity was observed to be lower than that of bulk GaP.

Time dependent effects of adjuvant tamoxifen therapy on cerebrovascular disease: results from a randomised trial

Background:

Tamoxifen has been associated with an increased risk of stroke. There is, however, little information on the effect in the post-treatment period. Using data from the Swedish Breast Cancer Group adjuvant trial of 5 vs 2 years of tamoxifen treatment, we now report both short-term and long-term effects on morbidity as well as mortality because of cerebrovascular disease.

Methods:

Data from the Swedish National Hospital Discharge Registry combined with information from the Swedish Cause of Death Registry was used to define events of disease. Hazard ratios (HRs) were estimated using Cox regression.

Results:

Comparing patients randomised to 5 years of tamoxifen with patients randomised to 2 years of tamoxifen, the incidence of cerebrovascular diseases was increased (HR 1.70, 95% CI 1.05–2.75) during the active treatment phase and reduced after the active treatment period (HR 0.78, 95% CI 0.63–0.96), and the difference in HR between the two time-periods was significant (P=0.0033). The mortality from cerebrovascular diseases was increased during the treatment period (HR 3.18, 95% CI 1.03–9.87) and decreased during the post-treatment period (HR 0.60, 95% CI 0.40–0.90) with a significant difference in HR between the two periods of follow-up (P=0.0066). Similar results were seen for subgroups of cerebrovascular diseases, such as stroke and ischaemic stroke.

Conclusion:

In an adjuvant setting, tamoxifen was associated with an increased risk of cerebrovascular disease during treatment, but a decreased risk in the post-treatment period.

The location of lymphangiogenesis is an independent prognostic factor in rectal cancers with or without preoperative radiotherapy

BACKGROUND

Lymphangiogenesis and angiogenesis are essential for tumour development and progression. The lymphatic vessel density (LVD) and blood vessel density (BVD) and their relationship to outcome have been studied extensively, however the clinical significance of the location of LVD/BVD in tumour is not known. In the present study, the location and degree of LVD/BVD and their relationship to preoperative radiotherapy (RT), clinicopathological, histopathological and biological factors were studied in rectal cancer patients participating in a Swedish clinical trial of preoperative RT.

PATIENTS AND METHODS

The location and degree of LVD/BVD were analysed in primary tumours (n = 138/140) and in their subgroups of non-RT (n = 74) and RT (n = 64/66). Further, the degree of LVD/BVD was examined in the corresponding distant normal mucosa (n = 35/31) and adjacent normal mucosa (n = 72/91). All sections were immunohistochemically examined by using D2-40 and CD34 antibodies.

RESULTS

In the whole series of the patients, a higher LVD at the periphery was related to negative p53 expression (P = 0.03) and favourable survival independent of tumour-node-metastasis stage, differentiation and p53 expression (P = 0.03). LVD was increased in p53-negative tumours after RT (P = 0.01).

CONCLUSION

LVD at the periphery of the tumour was an independent prognostic factor in rectal cancer patients.

Hospitalization in adolescence affects the likelihood of giving birth: a Swedish population-based register study

AIM

To examine the effect of hospitalization during adolescence on the likelihood of giving birth.

METHODS

142 998 women born in 1973-75 were followed with the help of the Swedish Medical Birth Register (MBR) and the Swedish Total Population Register (TPR) up until the end of 2000 with respect to their likelihood of giving birth. All analyses were adjusted for parental socio-economic characteristics and factors related to the studied women's own birth.

RESULTS

The likelihood of giving birth between 20 and 27 years of age was positively affected by hospitalization at least once during adolescence according to the Swedish Hospital Discharge Register (HDR); adjusted hazard ratio (HR) = 1.32, 95% confidence interval: 1.29-1.35. Women hospitalized due to genitourinary diseases, respiratory diseases, abdominal problems and abuse of alcohol and drugs were more likely to have given birth during the study period, while hospitalizations according to cerebral palsy and congenital malformations tended to decrease childbearing. Women hospitalized due to psychiatric diseases had an increase likelihood of given birth at 20-24 years but a reduced thereafter.

CONCLUSION

A majority of the causes of hospitalization during adolescence increased the likelihood of giving birth between ages 20 to 27.

Clinical and biological significance of angiogenesis and lymphangiogenesis in colorectal cancer

BACKGROUND

Angiogenesis and lymphangiogenesis are essential for tumour development and progression. However, in colorectal cancer (CRC), the relationship between angiogenesis and clinical outcome is controversial, and the prognostic significance of lymphangiogenesis is not well examined because of the lack of specific a marker for lymphatic vessels.

AIMS

To evaluate blood microvessel density (MVD) following the proposed standard method for MVD assessment given by the first international consensus and lymphatic vessel density (LVD), and investigate their clinicopathologic and biologic significance in CRC.

METHODS

MVD and LVD in primary tumours (n=210), along with their corresponding adjacent normal mucosa (n=105) and distant normal mucosa (n=27) specimens, were immunohistochemically examined by using CD31 and D2-40 antibodies.

RESULTS

Both MVD and LVD were higher in tumour compared with the corresponding normal mucosa. In tumours, MVD was positively related to particular interesting new cysteine-histidine-rich protein (PINCH) expression (P=0.006), but not with clinicopathologic variables. LVD, in both intratumoural and peritumoural areas of tumours, was reversely related to Dukes' stage. There was no association between MVD or LVD and patients' survival (P>0.05).

CONCLUSIONS

Angiogenesis and lymphangiogenesis occurred in CRC development, but were not related to CRC patient prognosis. PINCH may play a potential role in tumour angiogenesis.

Heterochromatin variants in 109 ovarian cancer patients and 192 healthy subjects

Aberrations of the C-band region of chromosome no. 1 (1qh) were studied in 109 patients with ovarian cancer and 192 healthy subjects. The groups were compared for heterochromatin size variations, intrapair size asymmetry, and inversion. No significant correlation was found between the size of 1qh and ovarian cancer. Heterochromatin size asymmetry was estimated visually and determined by objective measurement of 1qh length or area; the methods show strong correlation. The measurements were normalised by comparison with the length or area of 16p or the entire chromosome no. 1. However, since good reliability was found by simply relating the 1qh size difference to the mean 1qh size, this was considered an appropriate and simpler method of normalisation. Asymmetry indices of length and area measurements correlated well, implying that the simpler method of length measurements can be readily used. 1qh asymmetry, measured objectively or estimated visually, was significantly increased in the cancer patient group. The incidence of C-band inversion was significantly increased in the patient group. Moreover, inversion increased significantly with increasing 1qh asymmetry.

Age-specific direct healthcare costs attributable to diabetes in a Swedish population: a register-based analysis

AIMS

The aim of this population-based study was to explore the age-specific additional direct healthcare cost for patients with diabetes compared with the non-diabetic population.

METHODS

In 1999-2005, patients with diabetes in the Swedish county of Ostergötland (n = 20,876) were identified from an administrative database. Cost data on the healthcare expenditure in primary healthcare, out-patient hospital care and in-patient care for the entire county population (n = approximately 415,000) in 2005 were extracted from a cost per patient (CPP) database, which includes information on all utilized healthcare resources in the county. Data on drug sales were obtained from the Swedish Prescribed Drug Register.

RESULTS

The cost per person was 1.8 times higher in patients with diabetes than in the non-diabetic population, 7.7 times higher in children and 1.3 times higher in subjects aged > 75 years. The additional cost per person for diabetes was euro 1971; euro 3930 and euro 1367, respectively, for children and subjects aged > 75 years. The proportion of total additional diabetes costs attributable to in-patient care increased with age from 25 to 50%; in-patient care was the most expensive component at all ages except in children, for whom visiting a specialist was most expensive. The diabetes-related segment of the total healthcare cost was 6.6%, increasing from 2.0% in children to 10.3% in the age group 65-74 years, declining to 6.2% in the oldest age group.

CONCLUSIONS

The direct medical cost of diabetes varies considerably by age. Knowledge about the influence of age on healthcare costs to society will be important in future planning of diabetes management.

Seasonal variation in the diagnosis of type 1 diabetes in south-east Sweden

With the aim to survey the seasonal pattern of diagnosis of type 1 diabetes we included all 1903 children <16 years of age and who had been diagnosed with type 1 diabetes between 1977 and 2001 in the south-east of Sweden. To investigate the seasonal pattern a mixture of two cosine functions was included in a logistic regression model. There was a clear seasonal variation over the years (p<0.001). Children in the oldest age group (11-15 years) showed the most obvious seasonal variation (p<0.001). Children with a short duration of symptoms had about the same seasonal variation as children with a long duration. Both children with and without an infection 3 months prior to diagnosis showed significant seasonal variation (p<0.001) although the seasonal pattern differed between the two groups (p<0.001). As the incidence of diabetes increased during the 25 years the study period was divided into periods of 5 years and it was only during the two last periods that significant seasonal variation occurred. There is a clear seasonal variation in diagnosis of type 1 diagnosis in children and the results suggest that children with a less aggressive disease process at diagnosis were most responsible for this variation. Children with and without prior infection showed a different seasonal pattern.

Attitude towards remission induction for elderly patients with acute myeloid leukemia influences survival

Combination chemotherapy may induce remission from acute myeloid leukemia (AML), but validated criteria for treatment of elderly are lacking. The remission intention (RI) rate for elderly patients, as reported to the Swedish Leukemia Registry, was known to be different when comparing the six health care regions, but the consequences of different management are unknown. The Leukemia Registry, containing 1672 AML patients diagnosed between 1997 and 2001, with 98% coverage and a median follow-up of 4 years, was completed with data from the compulsory cancer and population registries. Among 506 treated and untreated patients aged 70-79 years with AML (non-APL), there was a direct correlation between the RI rate in each health region (range 36-76%) and the two-year overall survival, with no censored observations (6-21%) (chi-squared for trend=11.3, P<0.001; r2=0.86, P<0.02, nonparametric). A 1-month landmark analysis showed significantly better survival in regions with higher RI rates (P=0.003). Differences could not be explained by demographics, and was found in both de novo and secondary leukemias. The 5-year survival of the overall population aged 70-79 years was similar between the regions. Survival of 70-79-year-old AML patients is better in regions where more elderly patients are judged eligible for remission induction.

Long germanium nanowires prepared by electrochemical etching

Germanium (Ge) nanowires have been produced by electrochemical etching of single-crystalline n-type Ge [100] in a HCl-containing aqueous electrolyte. Macropores could be etched at various etching currents after an optimized procedure for homogeneous pore nucleation was used. Because of the narrow band gap of Ge (0.66 eV), the leakage current through pore walls is much higher than that, for example, in Si, leading to a constant dissolution of the pore walls. At sufficiently high current densities, it is then possible to form nanowires with diameters determined by the width of the space charge region, ranging from roughly 50 to 500 nm, and a length of several hundred micrometers. The role of the space charge region for stabilizing pore formation and in the formation of nanowires will be discussed.

Intergenerational effects of preterm birth and reduced intrauterine growth: a population-based study of Swedish mother-offspring pairs

OBJECTIVE

To estimate the intergenerational effects of preterm birth and reduced intrauterine growth.

DESIGN

Population-based cohort study.

SETTINGS

Mother-first-born offspring pairs recorded in the Swedish Medical Birth Registry.

POPULATION

Children born before 2001 to 38 720 women born in 1973-75.

METHODS

The relationships between the mother's and the child's birth characteristics were estimated using logistic regression analysis. Adjustments were made for smoking habits, body mass index (BMI), and current and childhood socio-economic conditions. Analyses were performed on all mother-offspring pairs and on the pairs for which information on neither of the included background variables was missing (n= 24 520).

MAIN OUTCOME MEASURES

Preterm birth (<37 weeks of gestation) and small for gestational age (SGA) (<-2 SD of the Swedish standard).

RESULTS

Mothers who themselves had been born preterm were not significantly more likely to deliver their own children preterm, compared with those who had been born at term (adjusted OR 1.24, 95% CI 0.95-1.62). Also, preterm birth in the mothers did not influence the occurrence of SGA in the children. However, the odds ratio for giving birth to SGA and preterm children, respectively, was higher among SGA mothers (OR 2.68, 95% CI 2.11-3.41 and OR 1.30, 95% CI 1.05-1.61). Mothers whose intrauterine growth was moderately reduced but who did not meet the criterion of being born SGA were also at higher risk of giving birth to both preterm and SGA children, respectively.

CONCLUSIONS

The present study showed evidence of intergenerational effects of reduced intrauterine growth even when socio-economic factors as well as BMI and smoking were adjusted for. There was, however, no consistent intergenerational effect of preterm birth.

MEAD: an interdisciplinary study of the marine effects of atmospheric deposition in the Kattegat

This paper summarises the results of the EU funded MEAD project, an interdisciplinary study of the effects of atmospheric nitrogen deposition on the Kattegat Sea between Denmark and Sweden. The study considers emissions of reactive nitrogen gases, their transport, transformations, deposition and effects on algal growth together with management options to reduce these effects. We conclude that atmospheric deposition is an important source of fixed nitrogen to the region particularly in summer, when nitrogen is the limiting nutrient for phytoplankton growth, and contributes to the overall eutrophication pressures in this region. However, we also conclude that it is unlikely that atmospheric deposition can, on its own, induce algal blooms in this region. A reduction of atmospheric nitrogen loads to this region will require strategies to reduce emissions of ammonia from local agriculture and Europe wide reductions in nitrous oxide emissions.

Serum cholesterol and testicular cancer incidence in 45,000 men followed for 25 years

In a 25-year follow-up study of 44 864 men with measured serum cholesterol levels, the testicular cancer hazard ratios for the serum cholesterol categories 5.7–6.9 and ⩾7.0 mmol l⁻¹vs the reference category (<5.7 mmol l⁻¹) were 1.3 and 4.5, respectively; P-value for trend=0.005. This highly significant association suggests that high-serum cholesterol is a risk factor for testicular cancer.

The probability of giving birth among women who were born preterm or with impaired fetal growth: a Swedish population-based registry study

The primary aim of this study was to investigate whether women born prematurely or with impaired fetal growth have a reduced probability of giving birth. Using Swedish population-based registries, the authors identified 148,281 women born in 1973-1975 for follow-up until 2001. Of these women, 4.1% were born preterm and 0.32% very preterm, 0.29% were born with a very low birth weight, and 5.4% were small for gestational age. Outcome measures were the hazard ratios for giving birth during the study period. Adjustments were made for socioeconomic factors. Very-low-birth-weight women displayed a reduced probability of giving birth (hazard ratio = 0.74, 95% confidence interval: 0.60, 0.91), most apparent among women aged 25 or more years. There were also tendencies of reduced hazard ratios of giving birth among women born preterm or very preterm in this age interval. Women born small for gestational age (below -2 standard deviations) seemed to be more likely to have given birth (hazard ratio = 1.09, 95% confidence interval: 1.04, 1.14), but when a more extreme group of small-for-gestational-age women (below -3 standard deviations) was defined, the association was less evident (hazard ratio = 1.04, 95% confidence interval: 0.94, 1.16). The results suggest that very-low-birth-weight women and, possibly, women born preterm or very preterm have a reduced probability of giving birth, while the results regarding small for gestational age are less clear.

Identification of characteristic regions and representative stations: a study of water quality variables in the Kattegat

Gradients in nutrient distributions and the effects of eutrophication are common features in most coastal marine areas. These structures occur in aquatic systems due to spatial differences in hydrography, nutrient loading and key biogeochemical processes. Two statistical methods, cluster analysis and probability mapping, have been used in the present study to determine characteristics and patterns in water quality variables. Combined, these two methods provide a useful tool to statistically determine spatial homogeneity and representativity of areas and stations. A case study is presented here in which water quality variables (salinity, dissolved inorganic nitrogen, dissolved inorganic phosphorus and chlorophyll) in surface waters of the Kattegat are analysed for the time period 1993-1997. It was found that morphology, the proximity to sources of nutrient loading from land, nutrient uptake and the infrequent water exchange between the Baltic Sea in the south and the Skagerrak in the north all contribute to create distinct regions of water quality. Regions with concentrations significantly different from the overall mean are identified. In addition to identification of regions with similar characteristics, representative stations (as well as not representative stations) for the respective regions were made. This type of information can be used to design new or revise old monitoring programs.

Space-time clustering of childhood lymphatic leukaemias and non-Hodgkin's lymphomas in Sweden

BACKGROUND

The discussion concerning clusters of childhood leukaemia has mainly been focused on their relation to the time and place of diagnosis. Recently some studies have indicated clustering not only at diagnosis, but also around time and place of birth. Space-time clustering at time of birth could be of special interest if the aetiological agent is of infectious origin and the induction of leukaemia either occurs pre- or perinatally or an infection at that time favours a poor subsequent immune response to the agent.

METHODS

To identify possible space-time clustering we have used the close-pair method of Knox. One-thousand-twenty recorded cases (0-14 years) of childhood acute lymphatic leukaemia and 293 cases (0-14 years) of malignant non-Hodgkin's lymphoma from Sweden between 1973-1996 were analysed. The records include date of birth and of diagnosis as well as addresses at birth and at diagnosis.

RESULTS

A significant excess of case-pairs (25 observed, 14.9 expected, p = 0.01) was observed close in date and place of birth in the 4-14 year age group with acute lymphatic leukaemia (ALL). However there was no statistically significant clustering found around time of diagnosis. When the cases of leukaemia and the non-Hodgkin's lymphomas were combined no statistically significant clustering was obtained neither at birth nor at diagnosis.

CONCLUSIONS

This study strengthens the evidence of space-time clustering around the birth date in children whom later developed ALL. This observation is in support of the hypothesis that pre- or perinatal infections can induce a process leading to ALL.

A moderate intake of wine is associated with reduced total mortality and reduced mortality from cardiovascular disease

OBJECTIVE

The aim of this study was to investigate the effects of the consumption of wine, beer and distilled spirits on total mortality and on mortality from cardiovascular disease.

METHOD

The consumption of wine, beer and distilled spirits was assessed in 1,828 individuals by a psychiatrist. Subjects were selected according to expected level of need for health services, from a random sample of 24,043 individuals aged 18-65 years. Mortality was recorded after 22 years and the results related to those for the individuals not exposed to the factor examined. The results were adjusted for age, expected level of need for health services, total alcohol consumption, gender, body-mass index, tobacco use and social class.

RESULTS

Intake of wine once a week or more (compared with intake of wine less than once a week or not at all) was associated with a relative risk ratio of 0.58 for total mortality (95% CI: 0.40-0.84) and a relative risk ratio of 0.49 for mortality from cardiovascular disease (95% CI: 0.27-0.90). The risk reduction seemed to be confined to those consumers of wine who had an intake of less than 140 grams of alcohol per week and consumed the beverage once a week. Ex-drinkers had an increased relative risk ratio in total mortality compared with lifelong abstainers and individuals who consumed less than 50 grams of alcohol per week (relative risk ratio = 2.64; 95% CI: 1.56-4.49).

CONCLUSIONS

A low to moderate intake of wine seems, unlike the consumption of distilled spirits and beer, to be associated with reduced total mortality and reduced mortality from cardiovascular disease.

Changes in sexual behavior after orthopedic replacement of hip or knee in elderly males--a prospective study

The aim of this study was to investigate two questions: Does arthroplastic surgery affect the patient's status as being sexually active; and if patients are sexually active, does surgery affect their erectile function? The study was designed prospectively and the patients filled in a questionnaire concerning sexuality and erectile function before and 6 months after alloplastic hip-or knee surgery. Ninety-nine males were included, mean age 70.6 y. The results demonstrate that 17% of patients lost a sexual activity that they had preoperatively, and no one regained sexual activity after surgery. A correlation between increasing age and risk of losing sexual activity was demonstrated. 26.1% lost a normal erectile function they had preoperatively, while 6.7% regained normal erections. A similar correlation between increasing age and increased risk was demonstrated. From this study of elderly males undergoing orthopaedic alloplastic surgery it is concluded that the risk of losing sexual activity and erectile capability is increased after surgery, and especially in the group where sexual functions are already impaired.

Efficacy of pamidronate in breast cancer with bone metastases: a randomized, double-blind placebo-controlled multicenter study

PURPOSE

To evaluate the efficacy of pamidronate 60 mg i.v. q 4 weeks in women with advanced breast cancer with skeletal metastases.

PATIENTS AND METHODS

404 woman with skeletal metastases from breast cancer in Sweden and Norway were included in a randomized, placebo-controlled, multicenter study. Except for the study medication, other palliative treatment was chosen at the discretion of the physician. Skeletal related events, i.e. increased pain, treatment of hypercalcemia, pathologic fractures of long bones or pelvis, paralyses due to vertebral compression, palliative radiotherapy for skeletal metastases, surgery on bone and change of antitumor therapy were recorded every third month as well as a self-estimated pain-score using visual Analog Scales and analgesic consumption.

RESULTS

There was a significantly increased time to progression of pain (p < 0.01), to hypercalcemic events (p < 0.05) as well as for the cumulative number of skeletal related events (p < 0.01) in favor for the pamidronate group. No statistically significant reduction of pathologic fractures of long bones or pelvis, or pareses due to vertebral compression occurred. No statistically significant differences were found for the need of radiotherapy and surgery on bone. The pamidronate group faired better regarding performance status (p < 0.05). There was a statistically not significant lower consumption of opioid analgesics in the pamidronate group (p = 0.14).

CONCLUSION

Pamidronate 60 mg i.v. q 4 weeks reduces skeletal events and improves the quality of life in women with bone metastases from breast cancer.

Glutathione S-transferase T1 and M1 genotypes in normal mucosa, transitional mucosa and colorectal adenocarcinoma

Gene codings for glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) are polymorphic in humans with null genotypes present in approximately 20 and 50%, respectively. A significant excess of homozygous null GSTT1 and GSTM1 genotypes has been demonstrated among individuals with certain types of cancers. This finding suggests that GSTT1 and GSTM1 may play a role in tumour susceptibility. However, reports concerning colorectal cancer susceptibility are controversial. In the present study, we used a multiplex polymerase chain reaction (PCR) approach to identify and analyze simultaneously the genotypes of both the genes in 99 patients with colorectal cancer and 109 healthy controls. Compared with the control group, a significant excess of homozygous null genotypes for GSTT1 was found in normal mucosa among the cancer patients, but not for GSTM1. Both genes were more frequently deleted in tumours than in corresponding normal mucosa. Furthermore, GSTT1 null genotype in tumour tissue, was significantly related to old age and to poor differentiation of tumours. GSTM1 null genotype in tumour was more frequent in the rectal tumours compared with tumours of left colon and right colon. Our results suggest that individuals with GSTT1 null genotype may be genetically predisposed for an increased risk of developing colorectal cancer. Allele loss in tumour tissue, which reflects genetic instability, may be considered as a marker for evaluating clinico-pathological characteristics of the cancer patients.

Glutathione S-transferase T1 and M1 genotypes in normal mucosa, transitional mucosa and colorectal adenocarcinoma

Gene codings for glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) are polymorphic in humans with null genotypes present in approximately 20 and 50%, respectively. A significant excess of homozygous null GSTT1 and GSTM1 genotypes has been demonstrated among individuals with certain types of cancers. This finding suggests that GSTT1 and GSTM1 may play a role in tumour susceptibility. However, reports concerning colorectal cancer susceptibility are controversial. In the present study, we used a multiplex polymerase chain reaction (PCR) approach to identify and analyze simultaneously the genotypes of both the genes in 99 patients with colorectal cancer and 109 healthy controls. Compared with the control group, a significant excess of homozygous null genotypes for GSTT1 was found in normal mucosa among the cancer patients, but not for GSTM1. Both genes were more frequently deleted in tumours than in corresponding normal mucosa. Furthermore, GSTT1 null genotype in tumour tissue, was significantly related to old age and to poor differentiation of tumours. GSTM1 null genotype in tumour was more frequent in the rectal tumours compared with tumours of left colon and right colon. Our results suggest that individuals with GSTT1 null genotype may be genetically predisposed for an increased risk of developing colorectal cancer. Allele loss in tumour tissue, which reflects genetic instability, may be considered as a marker for evaluating clinico-pathological characteristics of the cancer patients.