Zooming in on size distribution patterns underlying species coexistence in Baltic Sea phytoplankton.

Scale is a key to determining which processes drive community structure. We analyse size distributions of phytoplankton to determine time scales at which we can observe either fixed environmental characteristics underlying communities structure or competition-driven size distributions. Using multiple statistical tests, we characterise size distributions of phytoplankton from 20-year time series in two sites of the Baltic Sea. At large temporal scales (5-20 years), size distributions are unimodal, indicating that fundamental barriers to existence are here subtler than in other systems. Frequency distributions of the average size of the species weighted by biovolume are multimodal over large time scales, although this is the product of often unimodal short-term (<1 year) patterns. Our study represents a much-needed structured, high-resolution analysis of phytoplankton size distributions, revealing that short-term analyses are necessary to determine if, and how, competition shapes them. Our results provide a stepping-stone on which to further investigate the intricacies of competition and coexistence.

The native bacterioplankton community in the central baltic sea is influenced by freshwater bacterial species.

The Baltic Sea is one of the largest brackish environments on Earth. Despite extensive knowledge about food web interactions and pelagic ecosystem functioning, information about the bacterial community composition in the Baltic Sea is scarce. We hypothesized that due to the eutrophic low-salinity environment and the long water residence time (>5 years), the bacterioplankton community from the Baltic proper shows a native "brackish" composition influenced by both freshwater and marine phylotypes. The bacterial community composition in surface water (3-m depth) was examined at a single station throughout a full year. Denaturing gradient gel electrophoresis (DGGE) showed that the community composition changed over the year. Further, it indicated that at the four extensive samplings (16S rRNA gene clone libraries and bacterial isolates from low- and high-nutrient agar plates and seawater cultures), different bacterial assemblages associated with different environmental conditions were present. Overall, the sequencing of 26 DGGE bands, 160 clones, 209 plate isolates, and 9 dilution culture isolates showed that the bacterial assemblage in surface waters of the central Baltic Sea was dominated by Bacteroidetes but exhibited a pronounced influence of typical freshwater phylogenetic groups within Actinobacteria, Verrucomicrobia, and Betaproteobacteria and a lack of typical marine taxa. This first comprehensive analysis of bacterial community composition in the central Baltic Sea points to the existence of an autochthonous estuarine community uniquely adapted to the environmental conditions prevailing in this brackish environment.

Age and gender differences in VO2max in Swedish obese children and adolescents.

AIM: To describe age and gender differences in estimated maximum oxygen uptake (VO2max) and participation in organized physical activity in Swedish obese children and adolescents, and compare the results with an age-matched reference group representative of the general population. METHODS: Two hundred and nineteen obese children (102 boys, 117 girls, aged 8-16 years, Body Mass Index (BMI) 24.3-57.0 kg.m-2) performed a submaximal bicycle ergometry test and an interview concerning participation in organized physical activity. RESULTS: The obese children had lower relative VO2max (p<0.001) than the reference group. In contrast to the reference group no age or gender differences were detected in the obese children aged 11-13 years and 14-16 years. With increased age (after 11 years) the obese children participated less in organized physical activity than the reference group (p<0.001). In obese adolescents, participation in organized physical activity in leisure time explained 7% and BMI 45% of the variance in relative VO2max. CONCLUSION: The obese children had lower relative VO2max, and participated less in organized physical activity than the reference group. The variance in relative VO2max was primarily explained by BMI. Obese adolescents, especially boys, were found to be at risk of physical inactivity.

Influence of weight loss on pain, perceived disability and observed functional limitations in obese women.

OBJECTIVES: To evaluate the effects of weight reduction by dieting on musculoskeletal pain, perceived disability and observed functional limitations in everyday life. SUBJECTS: : Female outpatients in weight-loss programmes at the Karolinska Hospital, who met the criteria for participating in this study: age 20-65 y and body mass index (BMI) > or =30 kg/m(2). In all, 57 entered the programme studied and 43 completed it. INTERVENTIONS: Diet programmes for 8-12 weeks and thereafter 6688 kJ/day for >52 weeks. MAIN OUTCOME MEASURES: Questionnaires on musculoskeletal symptoms and obesity-specific questions on basic activities of daily living (ADL), mobility, housework, occupational disability and activities outside home. Test protocol developed for observation of functional limitations in obese women. Assessments at baseline, after 12 and after 64 weeks of dieting. RESULTS: In all, 75% completed the study. Weight loss was 14% (14.7+/-6.1 kg) at 12 weeks and, due to a weight relapse, 10% (10.1+/-8.1 kg) at 64 weeks. At the end of the study period, the proportion of current pain from lower backs and feet had normalised. Important perceived improvements were ability to rise from having fallen over, to walk up stairs and to lift heavy things. Most functional limitations improved, such as climbing onto high stools, walking up stairs with grocery bags, doing pedicure, rising from floor or low furniture. The questionnaire results partly followed the weight development, but the observed improvements were long-lasting. CONCLUSIONS: Weight reduction had positive short-term effects on musculoskeletal pain, perceived disability and observed functional limitations. A partial weight relapse had some impact on perceived pain and disability, but not on observed limitations. The maintained improvements may be due to weight loss, but also less pain and increased physical activity.

Parallel DNA template preparation using a vacuum filtration sample transfer device.

Solid-phase techniques have facilitated the handling of biochemical analytes. This has stimulated the development of systems by which large sample panels can be analyzed with high levels of security and quality. We describe a sample transfer device based on the principle of vacuum filtration, which enables parallel handling of 96 samples of analytes bound to Sepharose beads. The tool was employed for strand separation of DNA samples, by attracting the beads to filter probes while passing them between the reagent solutions. The samples were analyzed using Pyrosequencing technology and proved to yield genotyping results of high quality. The presented sample preparation procedure provides an important link in the development of integrated systems for rapid genetic analysis at a low cost. In addition, the same filter could be reused extensively with very low risk for detectable cross-contamination between assays and without any reduction in processing capacity, thus further reducing the cost per analyzed sample.

Impact of overweight and obesity on health-related quality of life--a Swedish population study.

OBJECTIVE: To investigate the impact of overweight and obesity on health-related quality-of-life (HRQL) in the general population in western Sweden. DESIGN: Cross-sectional survey. SUBJECTS: A total of 5633 men and women aged 16-64 y born in Sweden. MAIN OUTCOME MEASURES: Scale and summary component scores of the SF-36 Health Survey. RESULTS: Obese men aged 16-34 y rated their HRQL lower than normal-weight men did on all four physical health scales of the SF-36 and on two of the four mental health scales. Obese women in the same age group rated their health worse than normal-weight women on three of the physical health scales. Thus, in younger men and women the analysis indicated a clearer negative association between obesity and physical health than between obesity and mental health. Obese women aged 35-64 y rated their health worse on all scales than normal-weight women did, while obese men in this age group rated their health worse on only two SF-36 subscales-physical functioning and general health perception. The massively obese men and women suffered from a poor level of HRQL. CONCLUSION: Not only does the level of obesity affect HRQL, the impact of overweight and obesity also differs by age and sex. The importance of aspects of both physical and mental health should be fully recognised.

Perceived disability and observed functional limitations in obese women.

OBJECTIVE: To describe perceived disability in obese women. DESIGN: Comparisons of perceived disability in obese women and in a normal-weight reference group regarding activities of daily life (ADL), mobility, housework and professional work as well as comparisons of perceived disability and observed functional limitations reported in a previous study. SUBJECTS: Fifty-seven consecutively selected obese female outpatients, mean age 44 y (body mass index (BMI) 37 kg/m2) and 22 voluntary referents, mean age 49 y (BMI 22 kg/m2). MAIN OUTCOME MEASURES: A pain questionnaire (for background data) and a disability questionnaire, which is new, detailed and specific with test-retest stability and content- and criterion-referenced validity. Comparisons of results from the questionnaire and a functional test regarding observations of similar functional limitations. RESULTS: The obese women perceived disability to a much higher extent (P<0.003) than did the normal-weight women. The main problems concerned occupational work in strenuous positions, strain and pain, sports, walking outdoors or on stairs, and moderate housework requiring squatting, stooping or lifting. Rising from sofas, pedicure and stress incontinence were problematic. The correlation between perceived disability and functional limitations was fairly good (r(s)=0.56) but ranged widely (r(s)=0.14-0.61). Within the group of obese women the disability neither correlated to BMI nor age, rather to lower-body pain. CONCLUSION: The disability questionnaire conveyed new and detailed information of disability problems in everyday life in obese women. It highlighted the difference between the disability these women may perceive and the functional limitations we can observe and measure. This result is of great clinical relevance in the care of obese women.

Mast cells express functional CD30 ligand and are the predominant CD30L-positive cells in Hodgkin's disease.

Hodgkin's disease (HD) tumours are characterized by the presence of few tumour cells, the Hodgkin and Reed-Sternberg (HRS) cells, surrounded by a large amount of non-neoplastic cells. The role of this cell infiltrate for the development of HD is not known. CD30, belonging to the tumour necrosis factor receptor superfamily, is highly expressed on HRS cells and believed to be involved in tumourigenesis and tumour progression. Tumour samples from 42 patients were immunohistochemically double-stained for tryptase, a mast cell-specific proteinase and CD30 ligand (CD30L). Tryptase-positive mast cells were present in all tumours. Of these cells, 50% expressed CD30L and 66% of the CD30L-positive cells were mast cells. CD30L mRNA in in vitro developed normal mast cells and malignant human and murine mast cell lines was detected using reverse transcription polymerase chain reaction. CD30L protein expressed on human mast cells was detected using flow cytometry. In a co-culture assay, the human mast cell line HMC-1 stimulated thymidine uptake in HRS cell lines, and the stimulation could be blocked using CD30L-specific monoclonal antibodies. In conclusion, mast cells are present in HD tumours and are the predominant CD30L-expressing cells. CD30L-CD30 interaction is a pathway by which mast cells may stimulate DNA synthesis in HRS cells.

Functional limitations linked to high body mass index, age and current pain in obese women.

OBJECTIVE: To describe functional limitations in obese women. DESIGN: Comparisons of functional limitations in obese women and in a normal-weight reference group regarding mobility, balance and housework transport. SETTING: A large room with a corridor and staircase nearby. SUBJECTS: Fifty-seven consecutively selected obese female outpatients, mean age 44 y, body mass index (BMI) 37 kg.m(-2), and 22 voluntary references, mean age 49 y, BMI 22 kg.m(-2). MAIN OUTCOME MEASURES: Pain questionnaire (for background data); a new valid and reliable test protocol measuring activities of daily life (ADL), pain and exertion, heart rate, balance and speed. RESULTS: The patients had problems in performing 13 of 16 actions compared with the references (P-values between 0.05 and 0.001). They moved more slowly and had difficulties and /or pain and exertion in flexibility tasks, balancing, activities at floor level (bending and kneeling), climbing stairs and carrying groceries. BMI (P=0.002), age (P=0.02) and current pain (P=0.02) from the lower body predicted functional limitation. CONCLUSIONS: The functional test reflected functional limitations in obese women, revealing difficulties and perceived pain in ADL. The test protocol can be used to evaluate the effects of training or dieting. For clinical use we recommend considering BMI, age and current pain for use when individualizing advice on training.

Voluntary associations for cancer patients in Sweden: supportive activities.

Our aim was to describe voluntary associations for patients with cancer in Sweden (n=108) and their activities, type and extent of member support, and the associations' collaboration with the health care system. A specially constructed questionnaire with structured and open questions was used for the investigation. The frequency of answers was 89%. The results show in the broadest sense that the associations have two missions. The direct patient-related mission concerns providing patients with support in the form of close proximity, approachability and through distribution of knowledge together with financial and practical support; the indirect patient-related mission deals with activities aimed at improving conditions for patients in general within the health care system and by influencing authorities as well as supporting family members and significant others and providing financing. The associations collaborate with the health care system, although they face difficulties in becoming 'sanctioned' and in establishing positive relationships with the health care community. The associations display a positive attitude towards their cause and the personal gratification that the voluntary work brings. In general, the findings indicate that the associations have a potential to help patients live and cope with their cancer disease.

Nitrogen and the Baltic Sea: managing nitrogen in relation to phosphorus.

The Baltic is a large, brackish sea (4 x 10(5) km2) extending from 54N to approximately 66N, with a fourfold larger drainage area (population 8 x 10(7). Surface salinity (2 to 8 PSU) and hence biodiversity is low. In the last century, annual nutrient loads increased to 10(6) metric tons N and 5 x 10(4) ton P. Eutrophication is evident in the N-limited south, where cyanobacteria fix 2 to 4 x 10(5) ton N each summer, Secchi depths have been halved, and O2-deficient bottom areas have spread. Production remains low in the P-limited north. In nutrient-enriched coastal areas, phytoplankton blooms, toxic at times, and filamentous macroalgae reduce amenity values. Loads need to be reduced of both N, to reduce production, and P, to limit N-fixing cyanobacterial blooms. When large N-load reductions have been achieved locally, algal biomass has declined. So far, P loads have been reduced more than N loads. If this continues, a P-limited Baltic proper may result, very different from previous N-limited conditions. Reaching the management goal of halved anthropogenic N and P loads at minimum cost will require better understanding of biogeochemical nutrient cycles, economic evaluation of proposed measures, and improved stakeholder participation.

An interview study of men discovering testicular cancer.

Testicular cancer affects men between 15 and 45 years old. The aim of this study was to show how men with testicular cancer discover their cancer, react to physical changes, and take action. In the follow-up phase, 21 who had undergone surgery for testicular cancer were interviewed. The results show clearly that the men focus on their physical pain. The progress from the discovery of changes in the testicular glands to medical care can be divided into three phases. In the first phase, "something has happened," the men consider the changes and try to define the reasons. In the second phase, "facing the situation," they consider the situation and decide whether to talk to someone. In the third phase, "seeking medical help," it is a question of seeking help and being confronted by the medical diagnosis. In terms of time, the progression in the current study took from 1 day to 1 year. The men sought help when complications arose that made normal daily functions difficult. Six of the men suspected that the cause of their problems was cancer. Almost half of the participants in this study, including the six who suspected cancer, did not talk to anyone before they decided to seek medical help. The men who did talk to other people did not seek medical help any more quickly than the other men. None of the men routinely inspected their bodies.

Rehabilitation of long-term sick-listed patients in Sweden through techniques of sports medicine.

Sweden has seen a sharp increase in sick-listing recently. A new rehabilitation programme was tested for patients with musculoskeletal pain applying the experiences from sports injury rehabilitation. In this programme, the danger of inactivity was emphasised, and the staff accepted that the process of restoring physical fitness may be accompanied by a temporary increase in pain. During an 11 month period, 101 patients began a 4-week rehabilitation programme. This programme was in action 5 days a week from 9AM to 4PM. Six patients broke off the programme. The remainder were called back for a follow-up 6 months later, a total of 83 patients attending. This follow-up showed that only 22% benefit. Significantly more men than women returned to work. After rehabilitation the patients perceived better health and their living habits normalized. In patients sick-listed for long periods, an intensive period of exercise based largely on sports medicine can lead to return-to-work, also in Sweden.

Intravenous hydroxyethylrutosides combined with long-term oral anticoagulation in atherosclerotic nonreconstructable critical leg ischemia: a retrospective study.

OBJECTIVE: To evaluate in a group of seriously diseased patients with nonreconstructable chronic critical leg ischemia (CLI), treated by a combination of i.v. hydroxyethylrutosides (HR)* and oral anticoagulation (AC) by warfarin, the short-term effects on the cutaneous microvascular blood perfusion of the soles of feet and especially the long-term clinical outcome in terms of amputation and death. DESIGN: A retrospective comparison between two groups of patients, HR + AC and a comparable reference group, fulfilling the same inclusion and exclusion criteria corresponding to the definition of CLI according to the Second European Consensus Document (1991). Clinical follow-up in both groups was made after 1, 3, 6, 12, and 24 months. SETTING: Patients were examined at university departments of clinical physiology with special interest in peripheral vascular disease, in cooperation with colleagues at university departments of surgery, internal medicine and dermatology of Karolinska Hospital, Södersjukhuset and Huddinge Hospital. PATIENTS: A total of seventy patients with CLI according to the definition of the Second European Consensus Document, 1991, ie, besides severe rest pain or ischemic lesions also a toe blood pressure < 30 mg Hg. Group with HR + anticoagulation (AC): 42 patients (19 diabetics, 23 nondiabetics). Reference group: 28 patients (18 diabetics, 10 nondiabetics). For distribution of age and toe blood pressure at baseline, see Table I. INTERVENTIONS: Therapy group: besides ordinary standard therapy, daily HR infusions for a mean period of 3.6 weeks + oral anticoagulation continued to the end of the study at 24 months. A comparable reference group on the same basic therapy but without the combination HR + AC. PARAMETERS IN EVALUATION: Short-term parameters: clinical data, skin temperature, and fluorescein imaging. Long-term outcome: amputation or death. RESULTS: Short-term and long-term results with HR + AC indicated that patients with severe CLI and very poor prognosis benefited in terms of survival and limb salvage from initial therapy with HR infusion combined with long-term oral anticoagulation. Results of this combined treatment seem at least comparable with those with i.v. prostacyclin analogies.

Lifestyle discussion in the provision of health care. An empirical study of patient-physician interaction.

The main issue explored is how patients and physicians communicate about lifestyle in the clinical encounter and what role this talk plays in terms of the outcome of the consultation. The data, collected at two primary health care centers, consist of 42 audiorecorded consultations. The analyses are based on these transcribed dialogues. Our study shows that communication about lifestyle issues is used as a source for determining what health care measures are relevant. Physicians provided a variety of types of information and explicit connections were made between lifestyle and the medical problem by physicians as well as patients. Within the process of reaching decisions on advice or treatment, two forms of interaction appeared referred to here as "paternalism" and "mutuality". In general, the results show that the physicians are very cautious about making explicit medical inferences concerning specific issues of the individual's lifestyle.

Activated transcription of the human neuropeptide Y gene in differentiating SH-SY5Y neuroblastoma cells is dependent on transcription factors AP-1, AP-2alpha, and NGFI.

Activated transcription of the human neuropeptide Y gene (NPY) was investigated in SH-SY5Y neuroblastoma cells at the onset of sympathetic neuronal differentiation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) and serum or by nerve growth factor (NGF). As determined by transient expression, two NGF response elements (REs) were required for transcription induced by NGF in SH-SY5Y cells with stable expression of an exogenous NGF receptor TRK-A gene (SH-SY5Y/trk). TPA treatment in the presence of serum induced NPY transcription in both wild-type SH-SY5Y (SH-SY5Y/wt) and SH-SY5Y/trk cells. A TPA RE (TRE), overlapping the proximal NGF RE, was identified by expression of the v-Jun oncoprotein that enhanced NPY transcription. Suppression of TPA-induced NPY transcription was obtained by expression of a dominant negative Jun protein, selective protein kinase C inhibition, or introduction of a mutated TRE, whereas NGF-induced NPY transcription was inhibited to a lesser degree. The transcription factor AP-2alpha was shown to bind cooperatively to the NPY promoter with either AP-1 or NGFI-A to the shared TRE and NGF RE and to the distal NGF RE, respectively. These results show that transcription factors AP-1, AP-2alpha, and NGFI-A are involved in activated NPY transcription during the onset of neuronal differentiation.

Two non-racemic preparations of a piperidine-based NMDA antagonist with analgesic activity.

(2R,3S,1'R)-3-(1-Hydroxy-2-phosphonoethyl)-2-piperidinecarboxyl ic acid 1 has been synthesized by two different methods. The NMDA receptor binding affinities (Ki values) are 74 nM for compound 1, and 64 nM for the corresponding ketone 2. The analgesic effects were evaluated using the mouse hot-plate test and the mouse formalin model. The ED50 values for the racemates of compounds 1 and 2, using the mouse hotplate and intrathecal injection, were 0.53 and 0.51 nmol, respectively.

Is walking for exercise too exhausting for obese women?

OBJECTIVES: As exhaustion and pain during walking seem to be common problems among obese women, we decided to analyse the relative oxygen cost (% VO2max) in obese women during level walking. SUBJECTS: Fifty-seven obese female outpatients, 44.1 +/- 10.7 y, BMI 37.1 +/- 3.4 kg.m-2. METHODS: Walking tests at a self-selected, comfortable speed were performed indoors. Speed was measured with a speedometer, oxygen consumption (VO2) with the argon-dilution method and oxygen cost was estimated. Heart rate was measured; perceived exertion and pain were assessed with Borg's Category Ratio scale, CR10. Maximum oxygen uptake (VO2max/kg) was predicted from a submaximum bicycle ergometry test. RESULTS: The women walked more slowly, 70.9 +/- 5.6 m.min-1 (P < 0.0001), and had higher VO2, 1.2 +/- 0.2 l.min-1 (P < 0.001), than normals. A majority experienced exertion and some experienced pain. Their VO2max/kg, 21.2 +/- 5.0 ml.kg-1.min-1, was less than for normals (P < 0.0001). The mean % VO2max during walking was 56%, which was higher than in normal subjects 36% (P < 0.0001). Significant correlations between % VO2max and VO2max/kg (P < 0.0001), heart rate during walking (P = 0.0009) and age (P = 0.0081), respectively, were found. CONCLUSION: Very low VO2max/kg in obese women, rather than severe obesity per se, seems the most important factor to cause high % VO2max during walking. This might explain why many obese women perceive the exertion to be excessive and cannot follow the advice of their clinicians to exercise through long and brisk walks.

Acid tolerance response and survival by oral bacteria.

Using 21 species of oral bacteria, representing six acidogenic genera, we undertook to determine whether the pH-limiting exponential growth is related to the ability of the organisms to generate an acid-tolerance response that results in enhanced survival at low pH. The lower pH limit of exponential growth varied by more than two units with that of Neisseria A182 at pH 6.34; growth of Lactobacillus casei RB1014 stopped at pH 3.81, with species of Actinomyces, Enterococcus, Prevotella and Streptococcus falling between these limits. The working hypothesis was that the organisms with the higher pH limits for growth are unable to respond to acidic environments in order to survive, whereas the more aciduric organisms would possess or acquire acid tolerance. Adaptation to acid tolerance was tested by determining whether the prior exposure of exponential-phase cells to a low, sub-lethal pH would trigger the induction of a mechanism that would enhance survival at a pH killing pH 7.5 control cells. The killing pH varied from pH 4.5 for Prevotella intermedia ATCC 25611 to pH 2.3 for the three Lactobacillus casei strains in the study, with the three Streptococcus mutans strains killed at pH 3.0 for 3 h. The adaptation experiments revealed three groups of organisms: non-acid-responders, generally representing strains with the highest terminal pH values; weak acid-responders in the middle of the pH list, generating low numbers of survivors at one or two pH values, and the aciduric, strong responders generating a high number of survivors at pH values in the range 6.0 to 3.5, but not at pH 7.5. Predominant among the latter group were the S. mutans and Lactobacilli casei strains, with the most significant adaptive response exhibited by S. mutans LT11 and S. mutans Ingbritt, involving a process that required protein synthesis. Time course experiments with the latter organisms indicated that 90-120 min was required after exposure to the triggering pH before the acid response was fully functional. These results indicate that the sudden exposure of strains of oral streptococci and lactobacilli, as well as Enterococcus faecalis, to pH values between 6.0 and 3.5 results in the induction of an acid tolerance response that enhances the survival of these strains at or below pH 3.5.