Deeply Virtual Compton Scattering at Next-to-Next-to-Leading Order.

Deeply virtual Compton scattering gives access to the generalized parton distributions that encode the information on the transverse position of quarks and gluons in the proton with dependence on their longitudinal momentum. In anticipation of the high-precision experimental data in a broad kinematic range from the Electron-Ion Collider, we have calculated the two-loop, next-to-next-to-leading order (NNLO) deeply virtual Compton scattering coefficient functions associated with the dominant Compton form factors H and E at large energies. The NNLO correction to the imaginary part of H appears to be rather large, up to factor 2 at the input scale Q^{2}=4 GeV^{2} for simple generalized parton distribution models, due to a cancellation between quark and gluon contributions.

Early recovery after surgery for radical cystectomy: comprehensive assessment and meta-analysis of existing protocols.

PURPOSE: Different enhanced recovery after surgery (ERAS) protocols (EP) for radical cystectomy (RC) have been published. Protocols highly differ in number of included items and specific measures. MATERIALS AND METHODS: A systematic review and meta-analysis on EPs in RC were performed using the databases MedLine, Cochrane Library, Web of science, and Google Scholar. The specific ERAS measures of the protocols were extracted, analyzed, and compared. Pooling of available outcome data was performed for length of stay, complications, readmission rate, and time to defecation. RESULTS: The search yielded a total of 860 studies of which 25 studies were included in qualitative and 22 in quantitative analysis. Oral bowel preparation (BP) was omitted in 24/25 (96%) EPs, optimized fluid management was administered in 22/25 (88%) EPs and early mobilization (postoperative day 1) in 21/25 (84%). Gum chewing (n = 12, 46%), metoclopramide (n = 11, 44%), and alvimopan (n = 6, 24%) were the most common measures to prevent postoperative ileus. Our meta-analysis revealed a significant benefit in favor of EPs for the outcome parameters length of stay [mean difference (MD) - 3.46 d, 95% confidence interval (CI) - 4.94 to - 1.98, p < 0.01], complications [Odds ratio (OR) = 0.76, 95% CI 0.61-0.94, p = 0.01] and time to defecation (MD - 1.37 d, 95% CI - 2.06 to - 0.69, p < 0.01). Readmission rate did not show a significant difference (OR = 0.73, 95% CI 0.52-1.03, p = 0.07). CONCLUSION: Current EPs focus on omitting oral BP, early mobilization, and optimized fluid management while they differ in methods preventing postoperative ileus. Our meta-analysis revealed a benefit in introducing these protocols into clinical practice.

[Primary Prevention in General Medical Practice: A Survey]. / Primärprävention in der Allgemeinarztpraxis: Eine Befragung.

AIM OF THE STUDY: According to the German social insurance code §20 Sec. 1, statutory health insurance companies can reimburse up to 80% of costs incurred by primary prevention programs in physical activity, nutrition, stress management and drug consumption. Whether and how many general practitioners (GPs) provide their patients with information on such programs as part of their own practice is unknown. In this study, we investigate to which primary prevention programs primary care physicians refer their patients and whether they take into account reimbursability of programs. METHODS: Between November 2010 and February 2011, all GPs with a practice in Berlin (n=1 168) received a questionnaire that assessed if patients were referred to prevention programs and the type of programs they were referred to, if they ensured they are reimbursable and if they themselves offered prevention programs. Descriptive statistics and multivariate logistic regression was used for analysis. RESULTS: Of 474 respondents (response rate: 41%), 67% were female. Of the respondents, 22% offered reimbursable prevention programs and 42% at out-of-pocket expense. Patients were referred to reimbursable programs by 63%. GPs younger than 50 were twice as likely to offer reimbursable programs in their practice compared to those older than 50 (OR=1.7; 95% KI 1.1-2,8; p-value 0.025). CONCLUSION: A successful implementation of the new German prevention law needs awareness among GPs about reimbursable prevention programs, which may be lacking in some groups.

[Preventive advice-giving: self-assessment of general practitioners in Brandenburg]. / Präventive Beratung: Selbsteinschätzungen Brandenburger Hausärzte.

INTRODUCTION: Improving individual health behaviour is a promising approach especially in cardiovascular prevention. In general practice, preventive advice-giving is hitherto put into practice insufficiently. The study explores which role general practitioners are willing and able to play in behaviour-oriented prevention. METHODS: 50% of general practitioners in Brandenburg (n=748) were randomly selected for the study. A standardised questionnaire was mailed to them in which their attitudes towards preventive advice-giving were measured using Likert scaling. Participation was anonymous. RESULTS: 37% of the physicians answered the questionnaire. Almost all of them see it as their responsibility to inform patients about possible reduction of lifestyle-dependent health risks and to motivate them accordingly. Self-assessment concerning advisory skills is predominantly positive (best for physical activity, worst for smoking cessation and sexual risk behaviour advice). Time resources for behaviour-oriented prevention are sparse. For this reason, the delegation of many advisory tasks to physician assistants is regarded positively. CONCLUSION: Most physicians see themselves as willing and able to perform behaviour-oriented prevention. Nevertheless, realising this task seems to be difficult, e. g., concerning the frame conditions of general practice. The role of general practitioners in prevention and health promotion should be defined more accurately.

Finite-t and target-mass corrections to deeply virtual compton scattering.

We carry out the first complete calculation of kinematic power corrections ~t/Q(2) and ~m(2)/Q(2) to the helicity amplitudes of deeply virtual Compton scattering. This result removes an important source of uncertainties in the quantum chromodynamics predictions for intermediate momentum transfers Q(2) ~ 1-10 GeV(2) that are accessible in the existing and planned experiments. In particular, the finite-t corrections are significant and must be taken into account in the data analysis.

Kinematic power corrections in off-forward hard reactions.

We develop a general approach to the calculation of kinematic corrections ∝t/Q(2), m(2)/Q(2) in hard processes which involve momentum transfer from the initial to the final hadron state. As the principal result, the complete expression is derived for the time-ordered product of two electromagnetic currents that includes all kinematic corrections to twist-four accuracy. The results are immediately applicable, e.g., to the studies of deeply virtual Compton scattering.

The lipoprotein of the outer membrane of Escherichia coli: a B-lymphocyte mitogen.

The lipoprotein of the outer membrane of Escherichia coli is a B-cell mitogen in mice. Polyclonal activation of B lymphocytes was measured by an increase in thymidine uptake, by the development of plaque-forming cells against densely coupled trinitrophenylated sheep red cells, and by selectively increased rates of synthesis and secretion of leucine-labeled IgM. Murein-free and muropeptides-containing lipoprotein are effective in B-cell activation, while free murein is inactive. Removal of ester-linked fatty acids from the amino-terminal end of the lipoprotein by alkaline hydrolysis abolishes the mitogenicity of the lipoprotein. B lymphocytes from high responder (C3H/Tif and BALB/c nu/nu) or from low responder (C3H/HeJ) mice to the mitogen lipopolysaccharide (LPS) both respond well to the lipoprotein. Anti-immunoglobulin antibodies inhibit the mitogenic stimulation of B cells by lipoprotein. A complex of structures including the Ig-receptor molecules, the LPS receptor, and the lipoprotein receptor appear involved in the regulation of mitogenic stimulation of B cells to proliferation and differentiation to IgM-secreting cells.

Counseling overweight patients: analysis of preventive encounters in primary care.

OBJECTIVE: The increasing prevalence of obesity requires particularly primary care providers to take action. The aim of this study was to analyze general practitioners (GPs) encounters with overweight and obese patients in primary care to test the hypothesis that patients with a BMI ≥ 30 kg/m² would have longer consultations focusing on lifestyle-related issues like nutrition and physical activity than those with a BMI < 30 kg/m². DESIGN: Cross sectional comparison of audiotaped encounters of patients with a BMI ≥ 30 kg/m² and those with a BMI < 30 kg/m². SETTING: Twelve GP surgeries in Berlin, Germany. PARTICIPANTS: Fifty patients who agreed to have preventive check-up encounters audiotaped. MAIN OUTCOME MEASURES: Based on the Roter Interaction ANALYSIS: System (RIAS) we assessed duration of encounter and the prevalence of GP statements regarding cardiovascular risks, nutrition and physical activity. RESULTS: An increased BMI was found to be a predictor for the length of encounters (P = 0.01), whereas the content of talks was mainly determined by the individual of GP and sex of the GP. Statements regarding cardiovascular risks were most frequent, followed by those regarding nutrition and physical activity. In this study the assessed physiological parameters were not associated with the specific contents of preventive encounters like nutrition or physical activity (P > 0.05). CONCLUSIONS: Our results indicate that GPs rarely use the check-up program to conduct lifestyle consultations with obese patients. Barriers to lifestyle counseling and possible solutions are discussed with a view to promoting individualized and target management of overweight patients.

Bacterial solutions to the iron-supply problem.

The insolubility of Fe3+ necessitates special mechanisms for iron acquisition in most organisms. Bacteria use siderophores to chelate Fe3+ and iron in heme, hemoglobin, transferrin and lactoferrin, and employ novel mechanisms for receptor-dependent iron transport and iron-regulated gene expression. These mechanisms involve transfer of energy from the cytoplasmic membrane to the outer membrane to drive active transport and might induce transcription of transport genes by transmitting a signal from the cell surface.

[The general practitioner's part in the initiation of diagnostic procedures in prostate cancer]. / Die Rolle des Hausarztes bei der Initiierung der Diagnostik des Prostatakarzinoms.

AIM: The aim of the study is the analysis of diagnostic procedures performed by general practitioners (GPs) leading to the detection of prostate cancer (PCA). PATIENTS AND METHODS: A retrospective evaluation was performed on all 406 patients who underwent ultrasound-supported transrectal multibiopsy of the prostate in our department between January 2004 and August 2005. The GPs were interviewed by use of standardised questionnaires concerning the indication for specific examinations, referrals to the specialist, the clinical findings and results, and the GPs own urological qualification. The rate of returned questionnaires was 72.9 % (105 of 144 GPs), therefore a study group (SG) of 295 patients (72.7 %) was formed. The mean age was 67.2 (40 - 90) years. RESULTS: In 190 patients (64.4 %) primary diagnostic measures were performed by the GP herself/himself. All the other patients had already been in urological specialist treatment (n = 43), were either referred directly to an urologist for primary diagnostics (n = 42) or were diagnosed during a hospital stay (n = 3). The reasons for the performed diagnostic measures were not to be found in 17 cases. In 50.8 % of all cases the initiation of preventive medical check-ups or determination of PSA levels was done at the patient's own request. 91 of 176 digital rectal examinations (DRE) performed by GPs showed suspect findings, leading to referral to the urologist in 62 cases. PSA levels of 105 patients measured by the GPs ranged between 0.0 and 1662 ng/mL with a mean level of 29.81 and a median of 6.20 ng/mL. In 75 cases the PSA level led to a referral to the urologist. In the case of 27 patients the referral was decided because of clinical symptoms. In 39.0 % (n = 115) of the SG a PCA was detected by biopsy. In 43.0 % (n = 64) of the patients originally examined by the GPs the suspected diagnosis of a PCA based on a pathological PSA level and/or DRE proved to be correct. The GPs stated in 35.2 % (n = 37) that they had spent a certain period of time in a urological department during their medical training. Concerning referrals and the positive predictive value of DRE, there was no statistically significant different to be found in GPs without urological training. CONCLUSION: Every fifth patient in the study group showed a histologically proven PCA that had initially been suspected by a GP based on a pathological PSA level and/or DRE. This underlines the value of preventive exams in the hands of GPs. In addition, the correct and sensible use of PSA levels controls by GPs as well as a pronounced desire for preventive medical check-ups on the patient's side was shown.

Active transport of an antibiotic rifamycin derivative by the outer-membrane protein FhuA.

BACKGROUND: FhuA, an integral membrane protein of Escherichia coli, actively transports ferrichrome and the structurally related antibiotic albomycin across the outer membrane. The transport is coupled to the proton motive force, which energizes FhuA through the inner-membrane protein TonB. FhuA also transports the semisynthetic rifamycin derivative CGP 4832, although the chemical structure of this antibiotic differs markedly from that of ferric hydroxamates. RESULTS: X-ray crystallography revealed that rifamycin CGP 4832 occupies the same ligand binding site as ferrichrome and albomycin, thus demonstrating a surprising lack of selectivity. However, the binding of rifamycin CGP 4832 is deviant from the complexes of FhuA with hydroxamate-type ligands in that it does not result in the unwinding of the switch helix but only in its destabilization, as reflected by increased B factors. Unwinding of the switch helix is proposed to be required for efficient binding of TonB to FhuA and for coupling the proton motive force of the cytoplasmic membrane with energy-dependent ligand transport. The transport data from cells expressing mutant FhuA proteins indicated conserved structural and mechanistic requirements for the transport of both types of compounds. CONCLUSIONS: We conclude that the binding of rifamycin CGP 4832 destabilizes the switch helix and promotes the formation of a transport-competent FhuA-TonB complex, albeit with lower efficiency than ferrichrome. Active transport of this rifamycin derivative explains the 200-fold increase in potency as compared to rifamycin, which is not a FhuA-specific ligand and permeates across the cell envelope by passive diffusion only.

[DNA sperm methylation in assisted reproductive techniques]. / Méthylation du spermatozoïde en Assistance médicale à la procréation (AMP).

In the last few years, many tests were developed to study the fertilizing properties of the spermatozoa. However none of them was useful to obtain a prognostic factor. Indeed, the integrity of the spermatic DNA is also necessary to a successful fertilization for obtaining a pregnancy. DNA integrity could be evaluated by the measurement of the level of DNA methylation. Indeed, in the mammals, the methylation of the ADN is involved in diverse processes amongst them the regulation of the genome expression during the embryonic development. The objective of this study is to evaluate the impact of the level of methylation of the spermatic DNA in the success of in vitro fertilization (IVF), in terms of rate of fertilization, quality of the embryos and rate of pregnancy. The immunostaining of the 5-methylecytosine, then the quantification by image analysis or with flow cytometry, allowed an objective evaluation of the level of total methylation of spermatic DNA. Our data show that the level of DNA methylation influences neither the fertilization rate nor the embryos quality. On the other hand, the rate of pregnancy is decreased if the total level of DNA methylation is lower than a threshold value. The level of spermatic DNA methylation represents a new parameter of spermatic maturation.

Energy-coupled transport and signal transduction through the gram-negative outer membrane via TonB-ExbB-ExbD-dependent receptor proteins.

Iron in the form of ferric siderophore complexes and vitamin B12 are transported through the outer membrane of Gram-negative bacteria by a mechanism which consumes energy. There is no known energy source in the outer membrane or in the adjacent periplasmic space so that energy is provided by the electrochemical potential across the cytoplasmic membrane. Energy flows from the cytoplasmic into the outer membrane via a complex consisting of the TonB, ExbB and ExbD proteins which are anchored in the cytoplasmic membrane. It is proposed that the TonB--ExbB--ExbD complex opens--via an energized conformation of the TonB protein--channels in the outer membrane, formed by proteins which serves as highly specific binding sites for the various ferric siderophores and vitamin B12. In addition, outer membrane receptors together with the TonB--ExbB--ExbD complex are directly involved in induction of the transcription of ferric citrate and pseudobactin transport genes of Escherichia coli and Pseudomonas putida, respectively.

Enterobacterial hemolysins: activation, secretion and pore formation.

Two types of enterobacterial hemolysins have been studied in detail: the Escherichia coli alpha-hemolysin and the Serratia marcescens hemolysin. Although they have similar properties, they differ entirely in the number and structure of the proteins that determine their hemolytic activities, in the mechanism and the subcellular location of activation and in their secretion mechanisms.

Changes in fluorescence of 8-anilino-1-naphthalene sulfonate after bacteriophage T5 infection of Escherichia coli. Initial fluorescence rise coincides with onset of rubidium efflux.

Escherichia coli cells pre-loaded with 86Rb+ begin to lose 86Rb+ immediately after phage T5 addition. The loss proceeds with negative-exponential (first-order) kinetics for up to approximately 15 min after phage addition. The constant which characterizes the rate of loss increases with increasing numbers of infecting phage per cell. It is known that anaerobic, fermenting cells of E. coli show a two-step increase in 8-anilino-1-naphthalene sulfonate (ANS) fluorescence upon infection with bacteriophage T5; the first rise begins immediately upon phage addition, the second 6 min later. The onset of 86Rb+ release, therefore, is correlated with the first fluorescence rise with respect to timing and response to the multiplicity of infection.

Coincidental deficiency of the posterior arch of the atlas and thalassaemia minor: possible pitfalls in a trauma victim.

Congenital abnormalities of the cervical spine are rare findings in trauma victims. Deficiency of the posterior arch of the atlas and coincidental thalassaemia minor are even more unusual. This case report is about a young female trauma victim with both abnormalities, a combination that has previously not been described in literature. The classification, as proposed by Currarino et al in 1994, and the importance of being aware of these abnormalities are discussed.

[Management of iatrogenic lesions of the spinal accessory nerve]. / Management iatrogener N.-accessorius-Läsionen.

Lesions of the spinal accessory nerve are usually iatrogenic, especially after lymph node extirpation on the neck. Between 1994 and 2003, 31 patients were operated on in the Neurosurgical Department of the University of Ulm for iatrogenic lesions of the XIth cranial nerve. Of 31 patients, 22 had undergone a previous lymph node extirpation, 2 had been injured during a selective peripheral denervation for spasmodic torticollis, and the other 7 patients by different causes. The neurosurgical intervention was performed 0-19 months after trauma (mean 7.2 months). All patients showed paresis/atrophy of the trapezius muscle, and the abduction of the shoulder was markedly reduced. Additional neck and/or shoulder pain was present in 29 of 31 cases. In seven cases, the nerve was compressed by scar tissue and subsequently treated by external neurolysis. Ten patients underwent an end-to-end anastomosis; autologous sural nerve grafting was necessary in 13 cases. After a mean follow-up of 12.6 months, 7 of 31 patients completely recovered. Of 31 patients, 19 experienced partial relief of pain and weakness. Only five patients remained unchanged. The clinical findings after autologous nerve grafting, end-to-end reconstruction, or external neurolysis did not show any significant differences. Microsurgical reconstruction of iatrogenic injury of the spinal accessory nerve is very promising if the interval between trauma and surgical revision is less than 6 months. Up to 12 months, partial recovery can be achieved. Outcome after longer delay is unsatisfactory.

Crystal structure of the antibiotic albomycin in complex with the outer membrane transporter FhuA.

One alternative method for drug delivery involves the use of siderophore-antibiotic conjugates. These compounds represent a specific means by which potent antimicrobial agents, covalently linked to iron-chelating siderophores, can be actively transported across the outer membrane of gram-negative bacteria. These "Trojan Horse" antibiotics may prove useful as an efficient means to combat multi-drug-resistant bacterial infections. Here we present the crystallographic structures of the natural siderophore-antibiotic conjugate albomycin and the siderophore phenylferricrocin, in complex with the active outer membrane transporter FhuA from Escherichia coli. To our knowledge, this represents the first structure of an antibiotic bound to its cognate transporter. Albomycins are broad-host range antibiotics that consist of a hydroxamate-type iron-chelating siderophore, and an antibiotically active, thioribosyl pyrimidine moiety. As observed with other hydroxamate-type siderophores, the three-dimensional structure of albomycin reveals an identical coordination geometry surrounding the ferric iron atom. Unexpectedly, this antibiotic assumes two conformational isomers in the binding site of FhuA, an extended and a compact form. The structural information derived from this study provides novel insights into the diverse array of antibiotic moieties that can be linked to the distal portion of iron-chelating siderophores and offers a structural platform for the rational design of hydroxamate-type siderophore-antibiotic conjugates.

Transcription of the region encoding the ferric dicitrate-transport system in Escherichia coli: similarity between promoters for fecA and for extracytoplasmic function sigma factors.

We have analyzed the molecular mechanism of regulation of the ferric dicitrate transport system in Escherichia coli (Ec), by studying the transcription of the regulatory and structural genes under various environmental conditions, and by determining the location of their transcriptional start points and promoter regions. We report here that the main species observed in Northern hybridization analyses were a 2.5-kb mRNA, encoded by the outer membrane protein receptor gene fecA, and a 1.5-kb mRNA encoded by a region including the fecIR genes. The synthesis of the 2.5-kb fecA mRNA is regulated by both citrate and iron. Furthermore, transcription of fecA is dependent on the presence of FecI. The promoter region for the fecA mRNA, a likely site of action for FecI, is not related to the consensus promoter region for sigma 70 RNA polymerase in Ec K-12. However, it shows greatest similarity with promoters of genes regulated by a new sub-family of sigma factors, i.e., the extracytoplasmic function (ECF) sigma factors, which are associated with the expression of genes involved in extracytoplasmic functions, suggesting that FecI may act as a specialized sigma factor. We also show that the fecB,C,D,E transport genes are linked in operon fashion to fecA. Since the levels of the fecB,C,D,E RNAs are extremely low, as compared to the level of fecA mRNA, it is likely that processing from the 3' end must occur and stop near the end of fecA where a hairpin structure is located.