Worlds apart or two sides of the same coin? Attitudes, meanings, and motives of potential oocyte and sperm donors in Austria.

PURPOSE: Gamete donors and recipients of such donations have been explored by previous studies, which mostly focus on post-donation scenarios. Our study analyses the general willingness to donate oocytes or sperm and focuses on differences between potential female and male donors in attitudes, meanings, and motives in a pre-donation setting. METHODS: An electronic survey (n = 555 students) was used in this anonymous observational study. To enable comparisons between men and women regarding their attitudes, meanings, and motives and their willingness to donate gametes, we designed two separate questionnaires. RESULTS: The sample was divided into three groups based on the willingness to donate: potential donors (n = 133; women: 48.1%, men: 51.9%); doubtful donors (n = 207; women: 75.8%, men: 24.2%); and non-donors (n = 215; women: 68.3%, men: 31.7%). The group of potential male donors (39.2%) was significantly larger than the group of potential female donors (16.9%). Significant differences regarding altruism, the meaning of one's self-worth, and passing on the own genes were found between doubtful and potential donors. Potential donors attached less value to altruism but more value to the enhancement of one's self-worth and passing on one's genes than doubtful donors. The motive of passing on one's genes and altruistic motives were more important to men than to women. CONCLUSION: This study helps to create a better understanding of potential donors in the existing donation framework and supports the evaluation of the given regimes in the context of designing an improved framework.

The impact of previous live births on peripheral and uterine natural killer cells in patients with recurrent miscarriage.

BACKGROUND: Peripheral and uterine natural killer cells (pNK and uNK cells) are key players in the establishment and maintenance of pregnancy and are disturbed in patients with recurrent miscarriage (RM). Different immunologic risk factors have been proposed between patients with primary RM (pRM, no previous live birth) and secondary RM (sRM, ≥ 1 previous live birth). However, so far, the study populations mainly consisted of small subgroups. Therefore, we aimed to analyse pNK and uNK cells in a large, well defined study population within a prospective study. METHODS: In total, n = 575 RM patients (n = 393 pRM, n = 182 sRM) were screened according to a standard protocol for established risk factors as well as pNK and uNK cells. Peripheral blood levels of CD45+CD3-CD56+CD16+ NK cells were determined by flow cytometry and uterine CD56+ NK cells by immunohistochemistry in mid-luteal non-pregnant RM patients. Exclusion of patients with ≥1 established risk factor revealed n = 248 idiopathic RM patients (iRM, n = 167 primary iRM (ipRM), n = 81 secondary iRM (isRM)). RESULTS: Patients with pRM and ipRM showed significant higher absolute numbers and percentages of pNK cells compared to sRM and isRM patients (pRM/ipRM vs sRM/isRM, mean ± SD /µl: 239.1 ± 118.7/244.9 ± 112.9 vs 205.1 ± 107.9/206.0 ± 105.6, p = 0.004/ p = 0.009; mean ± SD %: 12.4 ± 5.5/12.8 ± 5.4 vs 11.1 ± 4.6/11.1 ± 4.3, p = 0.001; p = 0.002). Only patients with isRM showed significantly higher uNK levels compared to patients with ipRM (mean ± SD /mm2 288.4 ± 239.3 vs 218.2 ± 184.5, p = 0.044). CONCLUSIONS: The demonstrated differences in pNK and uNK cells in RM patients depending on previous live birth might indicate differences in NK cell recruitment and potentially different underlying immune disorders between pRM and sRM. As there is an overlap in the distribution of the NK cell results, further studies with focus on NK cell function are needed in order to clearly identify RM patients with distinct immune abnormalities. The clinical relevance of our findings should be interpreted cautiously until specificity and sensitivity are further evaluated.

[Geriatric Trauma Center DGU®: Evaluation of clinical and economic parameters : A pilot study in a german university hospital]. / AltersTraumaZentrum DGU®: Evaluation klinischer und ökonomischer Parameter : Eine Pilotstudie an einer deutschen Universitätsklinik.

BACKGROUND: Previous studies on orthogeriatric models of care suggest that there is substantial variability in how geriatric care is integrated in the patient management and the necessary intensity of geriatric involvement is questionable. OBJECTIVE: The aim of the current prospective cohort study was the clinical and economic evaluation of fragility fracture treatment pathways before and after the implementation of a geriatric trauma center in conformity with the guidelines of the German Trauma Society (DGU). METHODS: A comparison of three different treatment models (6 months each) was performed: A: Standard treatment in Orthopaedic Trauma; B: Special care pathways with improvement of the quality management system and implementation of standard operating procedures; C: Interdisciplinary treatment with care pathways and collaboration with geriatricians (ward round model). RESULTS: In the 151 examined patients (m/w 47/104; 83.5 (70-100) years; A: n = 64, B: n = 44, C: n = 43) pathways with orthogeriatric comanagement (C) improved frequency of postoperative mobilization (p = 0.021), frequency of osteoporosis prophylaxis (p = 0.001) and the discharge procedure (p = 0.024). In comparison to standard treatment (A), orthogeriatric comanagement (C) was associated with lower rates of mortality (9% vs. 2%; p = 0.147) and cardio-respiratory complications (39% vs. 28%; p = 0.235) by trend. In this context, there were low rates of myocardial infarction (6% vs. 0%), dehydration (6% vs. 0%), cardiac dysrhythmia (8% vs. 0%), pulmonary decompensation (28% vs. 16%), electrolyt dysbalance (34% vs. 19%) and pulmonary edema (11% vs. 2%). Duration of stay in an intensive care unit was 29 h (A) and 18 h (C) respectively (p = 0.205), with consecutive reduction in costs. A sole establishment of a special care pathway for older hip fracture patients (B) showed a lower rate of myocardial infarction (A: 11%, B: 0%, C: 0%; p = 0.035). CONCLUSION: There was a clear tendency to a better overall result in patients receiving multidisciplinary orthogeriatric treatment using a ward visit model of orthogeriatric comanagement, with lower rates of cardiorespiratory complications and mortality. While special care pathways could reduce the rate of myocardial infarction in hip fracture patients, costs and revenues showed no difference between all care models evaluated. However, patients with hip fracture or periprosthetic fracture represent cohorts at clinical and economic risk as well.

Health-related quality of life in patients with polycystic ovary syndrome: validation of the German PCOSQ-G.

PURPOSE: Patients with polycystic ovary syndrome (PCOS) report a decreased health-related quality of life (HRQOL) and higher levels of psychological distress. Validated questionnaires are necessary to assess the impact of PCOS on patients' lives. The aim of the present study was to evaluate the German "Polycystic Ovary Syndrome Questionnaire" (PCOSQ-G). METHODS: The psychometric properties of the PCOSQ-G were investigated in PCOS patients with item-total correlation, internal consistency and test-retest reliability. Correlations with the Short-Form-36 Health Survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS-D) were calculated to evaluate the validity of the PCOSQ-G. Discriminatory validity was investigated through a receiver operating characteristic curve and independent sample t tests compared with healthy controls. RESULTS: Good psychometric properties were found for most items. Acceptable to high internal consistency was found for the total score (α = 0.94-0.95) and all subscales (α = 0.70-0.97). High test-retest reliability was found for the total score (0.86) and all subscales (0.81-0.90). The validity analyses showed that the PCOSQ-G total score was positively correlated with both SF-36 summary scales and was negatively correlated with both HADS subscales. Patients reported significantly lower values for the PCOSQ-G total score (p < 0.001) and all subscales, and the PCOSQ-G discriminated well between patients and healthy controls (AUC = 0.81, p < 0.001). CONCLUSIONS: PCOSQ-G is a reliable and valid tool to assess the HRQOL in patients with PCOS and can be used in future clinical research. Patients with PCOS exhibited an impaired HRQOL, which indicates the need for psychosomatic counseling.

Adenomyosis and endometriosis. Re-visiting their association and further insights into the mechanisms of auto-traumatisation. An MRI study.

PURPOSE: In a series of publications, we had developed the concept that uterine adenomyosis and pelvic endometriosis as well as endometriotic lesions at distant sites of the body share a common pathophysiology with endometriosis constituting a secondary phenomenon. Uterine auto-traumatization and the initiation of the mechanism of tissue injury and repair (TIAR) were considered the primary events in the disease process. The present MRI study was undertaken (1) to corroborate this concept by re-visiting, in view of discrepant results in the literature, the association of adenomyosis with endometriosis and (2) to extend our views concerning the mechanisms of uterine auto-traumatization. PATIENTS AND METHODS: MRI was performed in 143 women attending our center, in whom, on the basis of transvaginal sonography (TVS) and historical data, such as documented endometriosis and dysmenorrhea of various degrees of severity, the presence of uterine adenomyosis was suspected. In addition to the measurement of the diameter of junctional zone (JZ) of the anterior and posterior walls in the mid-sagittal plane, the diagnosis of adenomyosis was based on visualization, in that all planes were analyzed with scrutiny. By this method of "visualization" all transient enlargement of the JZ, such as peristaltic waves of the archimyometrium and sporadic neometral contractions that might mimic adenomyotic lesions could be excluded. At the same time, this method allowed to lower the limit of detection in terms of thickness of the JZ for assured diagnosis of adenomyosis. Furthermore, the localizations of the individual lesions, their shapes and patterns were described. RESULTS: With the method of 'visualization', the diagnosis of uterine adenomyosis could be verified in 127 of the 143 patients studied. The prevalence of endometriosis in adenomyosis was 80.6% and the prevalence of adenomyosis in endometriosis was 91.1%. As concluded from their localization within the uterine wall, the adenomyotic lesions predominantly developed in the median region of the upper two-thirds of the uterine wall. Cystic cornual angle adenomyosis was a distinct phenomenon that was only observed in patients suffering from extreme primary dysmenorrhea. Aside from this, the majority of the patients complained of primary dysmenorrhea (80%). On the basis of these findings and the fact that particularly extreme primary dysmenorrhea is associated with high intrauterine pressure, menstrual 'archimetral compression by neometral contraction' has to be considered as an important cause of uterine auto-traumatization in addition to uterine peristalsis and hyperperistalsis. Both mechanical functions of the non-pregnant uterus exert their strongest power in the upper region of the uterus, which is compatible with the predominant localization of the adenomyotic lesions. CONCLUSIONS: The data confirm our previous results of a high association of adenomyosis with endometriosis and vice versa. Our view of the mechanism of uterine auto-traumatization by mechanical functions of the non-pregnant uterus has to be extended, in that 'archimetral compression by neometral contractions' could be realized as the predominant cause of mechanical strain to the non-pregnant uterus. The data of this study confirm our concept of the etiology and pathophysiology of adenomyosis and endometriosis in that the process of chronic proliferation and inflammation is induced at the level of the archimetra by chronic uterine auto-traumatization. Furthermore, with respect to the diagnosis of uterine adenomyosis (and consequently endometriosis) this study shows a high degree of accordance between the findings in real-time TVS and MRI.

Impact of endometriosis on quality of life, anxiety, and depression: an Austrian perspective.

PURPOSE: Several studies on the quality of life in patients with endometriosis have been performed with conflicting results. This cross-section survey examines the influence of endometriosis on the psychological well-being and the quality of life and the incidence of anxiety and depression among these patients, recruited from a tertiary care center in Austria. METHODS: Three standardized questionnaires of 62 patients with endometriosis were evaluated: status of health questionnaire (SF-36), hospital anxiety and depression scale (HADS-D), and endometriosis health profile (EHP-30). Quality of life status (EHP-30) was compared with published samples of the Oxford hospital and the Charite Berlin. Chi-square tests, independent sample t-tests, and one-way independent ANCOVA's were used to compare SF- 36 and HADS- D scores to 61 healthy controls. Pearson product-moment-correlation coefficients were used to investigate correlations between symptoms of depression and anxiety in the patient sample. RESULTS: Moderate to severe anxiety symptoms were found in 29 %; depressive symptoms were present in 14.5 % of the patients. Both symptoms occurred in 12.9 %. We found significant better values in all subscales of the EHP compared to the Oxford and Berlin samples. The control sample showed significant better subjective general health (p < 0.001), vitality (p < 0.001), mental health (p < 0.001), and better emotional role functioning (p < 0.001). Participants age significantly influenced mental health and emotional role functioning. CONCLUSIONS: The impact of endometriosis on life quality in our study was considerably less than in other studies but equivalent to other chronic medical conditions. It could be shown that endometriosis is influenced by biopsychosocial variables. However, the elevated presence of anxiety and depressive symptoms indicates the need of psychosomatic treatment of affective disorders to prevent manifestation.

A first-in-human study of PDC31 (prostaglandin F2α receptor inhibitor) in primary dysmenorrhea.

STUDY QUESTION: What is the safe and pharmacodynamically active dose range for PDC31 (prostaglandin F2α receptor inhibitor) in patients with primary dysmenorrhea (PD)? SUMMARY ANSWER: The 1 mg/kg/h dose of PDC31 appears to be safe and potentially effective in reducing intrauterine pressure (IUP) and pain associated with excessive uterine contractility when given as a 3-h infusion in patients with PD. WHAT IS KNOWN ALREADY: PDC31 has previously been shown to reduce the duration and strength of PGF2α-induced contractions in human uterine myometrial strip models and to delay delivery in animal models of preterm labor. STUDY DESIGN, SIZE, DURATION: This was a prospective, multi-center, dose-escalating first-in-human Phase I study conducted from March 2011 to June 2012. A total of 24 women with PD were enrolled and treated with one of five doses (0.01, 0.05, 0.15, 0.3, 0.5 and 1 mg/kg/h) of PDC31 given as a 3-h infusion. Patients were observed for a further 24 h. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study was conducted at four hospitals in Europe in non-pregnant, menstruating women with PD. Women with PD (n = 24) received PDC31 infused over 3 h within 8-10 h of the onset of menstruation. IUP and pain monitoring through the visual analog scale (VAS) was assessed prior to, during and following the infusion. Patients were observed for dose-limiting toxicities and other adverse events. Pharmacokinetic samples were also taken to profile the drug. MAIN RESULTS AND THE ROLE OF CHANCE: A 3-h infusion of PDC31 was safe up to and including doses of 1 mg/kg/h. Most adverse events were mild (n = 15; 83.3%) and not considered associated with PDC31 (n = 14; 77.8%). PDC31 infusion decreased uterine activity based on IUP and pain (VAS) scores. IUP was decreased by 23% over all dose levels, reaching a minimum at 135-150 min. There appeared to be a dose-dependent effect on IUP, with the high dose group (1 mg/kg/h) showing the largest decrease in IUP. There was a statistically significant linear dose-effect and concentration-effect relationship for several IUP parameters over the evaluation period of 60-180 min. A dose differentiating effect on pain was seen with the two highest doses. PDC31 demonstrated uncomplicated, linear pharmacokinetics with a terminal half-life of ∼2 h. LIMITATIONS, REASONS FOR CAUTION: This was a first-in-human study and exposure to PDC31 was limited for safety reasons. As such, pharmacodynamic parameters were assessed at a two-sided Type I error of 20%, an appropriate level for the exploratory nature of this study without a placebo control arm. This limited the chance of false positive findings to one in five. WIDER IMPLICATIONS OF THE FINDINGS: Like PD, preterm labor is associated with prostaglandin-mediated uterine contractions; therefore, the findings of this study support further development of PDC31 as a treatment for both PD and preterm labor. STUDY FUNDING/COMPETING INTERESTS: This work was funded by PDC Biotech GmbH, Vienna, Austria. B.B., R.M.L., L.W., R.J.S., K.J.B. and C.F.S. received reimbursement for the conduct of this study from PDC Biotech GmbH. W.H., M.S. and R.P.S. are paid consultants for PDC Biotech GmbH. P.G. is a paid consultant and shareholder of PDC Biotech GmbH. TRIAL REGISTRATION NUMBER: NCT01250587 at www.clinicaltrials.gov.

Ultrasonographic assessment of skin thickness in patients with PCOS - a case-control study.

OBJECTIVE: To measure skin thickness in patients with polycystic ovary syndrome (PCOS) in comparison to controls and to examine a possible association with sex steroids, body mass index, lipid profile and hyperinsulinemia. METHODS: Thirty patients with confirmed PCOS were compared to thirty-two women presenting for infertility workup. Skin thickness was measured using high-resolution ultrasound in a standardized area, blood samples were collected once at presentation. RESULTS: Patients with PCOS showed a statistically significant thicker skin than women in the control group (0.95 mm (±0.093 mm) versus 0.85 mm (±0.077 mm, p < 0.0001)). LH, estradiol, testosterone, the free androgen index, triglycerides, cholesterol, LDL-cholesterol and body mass index were significantly increased in PCOS - patients. No correlation between hyperinsulinemia and skin thickness was seen. CONCLUSIONS: PCOS - patients showed a greater skin thickness in comparison to women without PCOS. This might be due to proliferative effects of sex steroids such as estrogens and testosterone and metabolic derangements on skin thickness.

Numerical modeling of microplastic interaction with fine sediment under estuarine conditions.

Microplastic (MP) pollution is an important challenge for human life which has consequently affected the natural system of other organisms. Mismanagement and also careless handling of plastics in daily life has led to an accelerating contamination of air, water and soil compartments with MP. Under estuarine conditions, interactions with suspended particulate matter (SPM) like fine sediment in the water column play an important role on the fate of MP. Further studies to better understand the corresponding transport and accumulation mechanisms are required. This paper aims at providing a new modeling approach improving the MP settling velocity formulation based on higher suspended fine sediment concentrations, as i.e. existent in estuarine turbidity zones (ETZ). The capability of the suggested approach is examined through the modeling of released MP transport in water and their interactions with fine sediment (cohesive sediment/fluid mud). The model results suggest higher concentrations of MP in ETZ, both in the water column as well as the bed sediment, which is also supported by measurements. The key process in the modeling approach is the integration of small MP particles into estuarine fine sediment aggregates. This is realized by means of a threshold sediment concentration, above which the effective MP settling velocity increasingly approaches that of the sediment aggregates. The model results are in good agreement with measured MP mass concentrations. Moreover, the model results also show that lighter small MP particles can easier escape the ETZ towards the open sea.

The assembly-activating protein promotes capsid assembly of different adeno-associated virus serotypes.

Adeno-associated virus type 2 (AAV2) capsid assembly requires the expression of a virally encoded assembly-activating protein (AAP). By providing AAP together with the capsid protein VP3, capsids are formed that are composed of VP3 only. Electron cryomicroscopy analysis of assembled VP3-only capsids revealed all characteristics of the wild-type AAV2 capsids. However, in contrast to capsids assembled from VP1, VP2, and VP3, the pores of VP3-only capsids were more restricted at the inside of the 5-fold symmetry axes, and globules could not be detected below the 2-fold symmetry axes. By comparing the capsid assembly of several AAV serotypes with AAP protein from AAV2 (AAP-2), we show that AAP-2 is able to efficiently stimulate capsid formation of VP3 derived from several serotypes, as demonstrated for AAV1, AAV2, AAV8, and AAV9. Capsid formation, by coexpressing AAV1-, AAV2-, or AAV5-VP3 with AAP-1, AAP-2, or AAP-5 revealed the ability of AAP-1 and AAP-2 to complement each other in AAV1 and AAV2 assembly, whereas for AAV5 assembly more specific conditions are required. Sequence alignment of predicted AAP proteins from the known AAV serotypes indicates a high degree of homology of all serotypes to AAP-2 with some divergence for AAP-4, AAP-5, AAP-11, and AAP-12. Immunolocalization of assembled capsids from different serotypes confirmed the preferred nucleolar localization of capsids, as observed for AAV2; however, AAV8 and AAV9 capsids could also be detected throughout the nucleus. Taken together, the data show that AAV capsid assembly of different AAV serotypes also requires the assistance of AAP proteins.

Hormonal contraception and depression: a survey of the present state of knowledge.

PURPOSE: Depressive symptoms often occur among women of reproductive age. In this article we perform an analysis of existing studies to examine a possible correlation between depression and the use of hormone-based contraceptives. METHODS: The computerized databases MEDLINE/PubMed were searched for studies examining the relation between depressive disorders and hormonal contraception of the years 1976-2010. RESULTS: Data on this topic are limited. At least two confounding variables influence the analysis of the available data and make it difficult to draw firm conclusions: the inconsistent use of the term "depression" and the large number of combined contraceptives which vary in their composition. The association between the use of oral contraceptives and depression is not clear. We found that depression is not a common side effect of hormone-based contraceptives. CONCLUSION: Individual, patient-based decisions with consideration of the individual history and predispositions are recommended when starting oral contraceptives. If depressive symptoms or mood changes occur, decisions regarding discontinuation or medication change need to be made on an individual basis.

Infection control measures in neonatal units: implementation of change in the Gaza-Strip.

Introduction: Low-income countries rarely report infection control measures although they are key to reducing mortality and morbidity in healthcare. This audit examined healthcare personnel's adherence to infection control measures before entry to the NICU and in both minor and major procedures' bundles. Furthermore, it examined the effect of subsequent authorization and dissemination of infection control guidelines followed by education and training sessions on the adherence of healthcare personnel to infection control policies.Methods: This prospective observational study was conducted in two NICUs at two separate hospitals in the Gaza-Strip, Palestine. The initial observation period was June-August 2016 during which healthcare professionals' adherence to infection control policies was assessed by direct observation. This was followed by NICU feedback dissemination and on-site educational and training sessions. Then, the reaudit, following the same protocol, was carried out throughout February 2017.Results: There was a statistically significant improvement in the adherence to infection control measures among healthcare personnel. Significant improvements were found in both minor and major procedure infection control protocols' adherence rates. However, when comparing the general neonatal handling adherence rate between both audits, no significant change was noted.Discussion: This study highlights the effectiveness of using audit feedback and on-site educational and training sessions in the enhancement of adherence to infection control policies, demonstrating significant improvement in areas covered by the staff training program. Therefore, including regular infection control training combined with feedback in the curriculum of healthcare professionals can improve the sustainability of infection control programs. Further studies must examine the impact of such training also on the incidence of healthcare-associated infection rates as well as morbidity and mortality within neonatal units.

Manifestation of migraine in adolescents: Does it change in puberty?

PURPOSE: To analyze the association between pubertal stage, menstrual cycle and migraine attacks in girls with migraine. In addition, headache frequency, accompanying symptoms, duration and onset in relation to the specific phase of the cycle were investigated. METHODS: Girls between 7 and 18 years old, diagnosed with headaches that met "International Classification of Headache Disorders II" diagnostic criteria for migraine without aura, kept a daily headache and menstrual cycle diary over 8 weeks. Ovulatory cycles were identified by weekly progesterone saliva tests. RESULTS: 47 girls participated in the study and were divided into three groups according to Tanner stage and onset of regular menstruation: pre- (n = 16), peri- (n = 19) and post-pubertal (n = 12). A significant difference in migraine frequency was found between pre- and post-pubertal girls (p = 0.005). No significant differences with regard to headache characteristics were detected. Interestingly, a higher frequency of attacks in follicular phase occurred compared to luteal phase in peri- and post-pubertal girls (p = 0.030). CONCLUSION: During puberty, migraine patterns in girls change to a typical adult pattern of migraine in a stepwise manner not clearly related to menarche. The first sign of this transition phase could be the higher frequency of migraine attacks in post-pubertal girls.

Difference imaging reveals ordered regions of RNA in turnip yellow mosaic virus.

BACKGROUND: Turnip yellow mosaic virus (TYMV) is a small icosahedral plant virus with a capsid containing 180 subunits arranged with hexamer-pentamer clustering. Cross-linking studies have indicated extensive contacts between RNA and coat protein, suggesting that substantial parts of the RNA might be icosahedrally ordered. RESULTS: Comparison of maps computed to a Fourier cut-off of 1.5 nm from electron micrographs of ice-embedded specimens of TYMV and of empty capsids produced by freeze-thawing reveals strong inner features around the threefold axes in the virus but not in the empty capsid. Internal features of subunit packing indicate that interhexamer contacts are closer than those between pentamers and hexamers and that pentamer density in the empty capsid is reduced relative to that in the virus. CONCLUSIONS: The differences between virus and empty capsid indicate that substantial parts of the RNA are icosahedrally ordered and that the exit of RNA on freeze-thawing is accompanied by the loss of at least one pentamer unit.

Metabolic performance of the coral reef fish Siganus guttatus exposed to combinations of water borne diesel, an anionic surfactant and elevated temperature in Indonesia.

Jakarta Bay in Indonesia and its offshore island chain, the Thousand Islands, are facing extreme pollution. Surfactants and diesel-borne compounds from sewage and bilge water discharges are common pollutants. However, knowledge of their effects on reef fish physiology is scarce. This study investigated combined and single effects of a) the water accommodated fraction of diesel (WAF-D, determined by Æ©EPA polycyclic aromatic hydrocarbons (PAHs)) and b) the surfactant linear alkylbenzene sulfonate (LAS) on metabolic performance of the coral reef fish Siganus guttatus. Responses to combinations of each pollutant with elevated temperature (+3°C) were determined. Short-term exposure to WAF-D led to a significant decrease in standard metabolic rates, while LAS led to an increase. During combined exposure, metabolic depression was observed. Effects of pollutants were not amplified by elevated temperature. This study highlights the need to reduce import of these pollutants and to avoid negative long-term effects on fish health.

The structure of the H(+)-ATP synthase from chloroplasts and its subcomplexes as revealed by electron microscopy.

The electron microscopic data available on CF(0)F(1) and its subcomplexes, CF(0), CF(1), subunit III complex are collected and the CF(1) data are compared with the high resolution structure of MF(1). The data are based on electron microscopic investigation of negatively stained isolated CF(1), CF(0)F(1) and subunit III complex. In addition, two-dimensional crystals of CF(0)F(1) and CF(0)F(1) reconstituted liposomes were investigated by cryo-electron microscopy. Progress in the interpretation of electron microscopic data from biological samples has been made with the introduction of image analysis. Multi-reference alignment and classification of images have led to the differentiation between different conformational states and to the detection of a second stalk. Recently, the calculation of three-dimensional maps from the class averages led to the understanding of the spatial organisation of the enzyme. Such three-dimensional maps give evidence of the existence of a third connection between the F(0) part and F(1) part.

The structure of Photosystem I from the thermophilic cyanobacterium Synechococcus sp. determined by electron microscopy of two-dimensional crystals.

The structure of the Photosystem I (PS I) complex from the thermophilic cyanobacterium Synechococcus sp. has been investigated by electron microscopy and image analysis of two-dimensional crystals. Crystals were obtained from isolated PS I by removal of detergents with Bio-Beads. After negative staining, either single layers or two superimposed layers with a rotational different orientation were observed. The layers have a rectangular unit cell of 16.0 x 15.0 nm, which contains two PS I monomers. The monomers are arranged alternating up and down in each layer. For double-layer crystals, the images of the two layers could be separately processed by a combination of Fourier-peak-filtering and correlation averaging. Features in the two-dimensional plane can be seen with a resolution up to 1.5-1.8 nm. A model for the PS I structure was obtained by combining three-dimensional reconstructions from three tilt-series. The model shows an asymmetric PS I complex. On one side (presumably the stromal side) there is a 3 nm high ridge. This is most likely comprised of the psaC, psaD and psaE subunits. The other side (presumably the lumenal side) is rather flat, but in the center there is a 3 nm deep indentation, which possibly separates partly the two large subunits psaA and psaB.

Direct indication for the existence of a double stalk in CF0F1.

The H+-ATPase from chloroplasts (CF0F1) was investigated by electron microscopy of negatively stained single molecules followed by image processing. The analysis of about 4700 particles from 72 micrographs gave clear evidence that the membrane-integrated F0 part is connected by at least two stalks to the F1 part. One of the two stalks is more prominent and connects a central part of F1 with a slightly peripheral part of F0. The other stalk connects a peripheral part of F1 to a peripheral part of F0.

Direct visualisation of conformational changes in EF(0)F(1) by electron microscopy.

The isolated H(+)-ATPase from Escherichia coli (EF(0)F(1)) was investigated by electron microscopy of samples of negatively stained monodisperse molecules, followed by single-particle image processing. The resulting three-dimensional maps showed that the F(1)-part is connected by a prominent stalk to a more peripheral part of F(0). The F(1)-part showed stain-accessible cavities inside. In three-dimensional maps from selected particles, a second stalk could be detected which was thinner than the main stalk and is thought to correspond to the stator.Three-dimensional maps of the enzyme in the absence and in the presence of the substrate analogue adenyl-beta, gamma-imidodiphosphate (AMP-PNP) were calculated. Upon binding of AMP-PNP the three-dimensional maps showed no significant changes in the F(0)-part of EF(0)F(1), whereas a major conformational change in the F(1)-part was observed. (1) The diameter of the F(1)-part decreased upon binding of AMP-PNP mainly in the upper half of F(1). (2) Enzyme particles prepared in the presence of AMP-PNP had a pointed cap at the top of the F(1)-part which was missing in its absence. (3) The stain-accessible cavity inside the F(1)-part altered its pattern significantly.