The RNA repair proteins RtcAB regulate transcription activator RtcR via its CRISPR-associated Rossmann fold domain

CRISPR-associated Rossmann fold (CARF) domain signaling underpins modulation of CRISPR-Cas nucleases; however, the RtcR CARF domain controls expression of two conserved RNA repair enzymes, cyclase RtcA and ligase RtcB. Here, we demonstrate that RtcAB are required for RtcR-dependent transcription activation and directly bind to RtcR CARF. RtcAB catalytic activity is not required for complex formation with CARF, but is essential yet not sufficient for RtcRAB-dependent transcription activation, implying the need for an additional RNA repair-dependent activating signal. This signal differs from oligoadenylates, a known ligand of CARF domains, and instead appears to originate from the translation apparatus: RtcB repairs a tmRNA that rescues stalled ribosomes and increases translation elongation speed. Taken together, our data provide evidence for an expanded range for CARF domain signaling, including the first evidence of its control via in trans protein-protein interactions, and a feed-forward mechanism to regulate RNA repair required for a functioning translation apparatus.

Early aortic valve replacement improves exercise capacity in truly asymptomatic patients with severe aortic stenosis

Background

Exercise capacity is a strong predictor of morbidity and mortality overall. In severe aortic stenosis (AS) ustained pressure overload during watchful waiting is associated with LV structural and functional deterioration and impaired clinical outcome both pre- and post aortic valve replacement (AVR). The effect of early surgical aortic valve replacement (SAVR) in asymptomatic patients with severe AS and normal left ventricular function on exercise capacity in unknown.

Aim

We investigated whether the early surgical AVR in truly asymptomatic patients with severe aortic stenosis and normal LVEF improves the exercise capacity.

Methods

This is a sub-analysis or the AVATAR trial (NCT02436655), which is international prospective randomized controlled trial that evaluated the safety and efficacy of early SAVR in the treatment of asymptomatic patients with severe AS, according to common criteria (valve area ≤1 cm2 with aortic jet velocity >4 m/s or a mean transaortic gradient ≥40 mm Hg), and with normal left ventricular function. Patients underwent cardiopulmonary exercise testing (supine bicycle, ramp protocol, 15 W/min) at the baseline and 12 months following the randomization. Patients who had positive exercise testing at baseline visit were excluded. We compared the value of workload (in WATs), VO2 max, VO2 AT, VE/VCO2 and PETCO2 slope at the inclusion and at 12 months.

Results

Total of 157 patients (mean age, 67 years; 57% men) were randomly allocated to early surgery (n=78) or conservative treatment (n=79). Mean LVEF and Vmax in early surgery and conservative treatment group were 70% and 4.5m/s and 69% and 4.5m/s, respectively. After 12 months in patients with conservative treatment there was a slight decrease in the values of workload, VO2 max, VO2 AT, VE/VCO2 and PETCO2 slope, but without statistical significance. However operated patients showed a significant increase in workload (115.4±38.4 watts at 12 months vs 104.8±42.2 at inclusion, p=0.038) and VO2 max (19.7±6.8 at 12 months vs 16.2±5.4 at the inclusion, p=0.048), while there was slight increase in the values of VO2 AT, VEVCO2 and PETCO2 but without statistical significance.

Conclusion

Early SAVR improve the functional capacity in asymptomatic patients with severe aortic stenosis and normal left ventricular ejection fraction

Funding Acknowledgement

Type of funding sources: None.

Structures of Class I and Class II Transcription Complexes Reveal the Molecular Basis of RamA-Dependent Transcription Activation

Transcription activator RamA is linked to multidrug resistance of Klebsiella pneumoniae through controlling genes that encode efflux pumps (acrA) and porin-regulating antisense RNA (micF). In bacteria, σ70 , together with activators, controls the majority of genes by recruiting RNA polymerase (RNAP) to the promoter regions. RNAP and σ70 form a holoenzyme that recognizes -35 and -10 promoter DNA consensus sites. Many activators bind upstream from the holoenzyme and can be broadly divided into two classes. RamA acts as a class I activator on acrA and class II activator on micF, respectively. The authors present biochemical and structural data on RamA in complex with RNAP-σ70 at the two promoters and the data reveal the molecular basis for how RamA assembles and interacts with core RNAP and activates transcription that contributes to antibiotic resistance. Further, comparing with CAP/TAP complexes reveals common and activator-specific features in activator binding and uncovers distinct roles of the two C-terminal domains of RNAP α subunit.

Prevalence and risk factors for thyroid cancer in patients with multinodular goitre

BACKGROUND

Rates of thyroid cancer in patients with multinodular goitre (MNG) vary widely, from 3 per cent in older studies to 35 per cent in more recent studies. The purpose of the present study was to evaluate the prevalence of thyroid cancer in patients operated on for MNG, and to determine risk factors for incidental thyroid malignancy.

METHODS

A prospectively developed database of all patients who underwent thyroidectomy for a benign MNG at the high-volume endocrine surgery unit of a tertiary referral university hospital was interrogated.

RESULTS

A total of 3233 patients were analysed, separated into three groups according to their functional thyroid status (hypothyroid, hyperthyroid or euthyroid). There were 2788 women (86.2 per cent); the mean patient age was 56.4 years and mean preoperative disease duration was 106.2 months. Incidental thyroid cancer was identified in 1026 patients (31.7 per cent), of which 917 (89.4 per cent) were papillary cancers. Multivariable regression analysis identified functional thyroid status, younger age, male sex, smaller adenoma size, smaller thyroid glands, Hashimoto's thyroiditis and chronic non-specific thyroiditis as independent risk factors for thyroid cancer.

CONCLUSION

MNG was associated with a considerable rate of incidental thyroid cancer, which has been underestimated. A variety of factors should be taken into account when considering the malignant potential of a presumed benign MNG.

Use of dietary supplements among male fitness club members in Nis, Serbia

Background

Dietary supplements use continues to increase in many countries. They are often used without a full understanding of the potential benefits and risks associated with their use, and without consultation with a health care professional. This study aimed to explore health beliefs and patterns of dietary supplement usage among fitness club participants.

Methods

This cross-sectional study was conducted in fitness clubs of the city of Nis, Serbia. Male adults, age 18-45 years, participated. Data from participants were collected through an original structured, self-administered questionnaire describes the prevalence and type of supplements used, the reasons for using and the information source.

Results

The prevalence of dietary supplement intake among participants was 85.86%. Most participants were between the age of 20 and 40 years, had a college degree (57.1%), non-smokers (80.5%), without chronic disease (86%), perform exercise at least thrice weekly (76.2%) and 63% had at least1 hour. The percentage of participants who had favorable health views on dietary supplements was significantly higher among the supplement users than among the non-users (P < 0.0001). Most participants (76.19%) perform exercise from 3 to 5 times weekly and 82.85% had from 1 to 2 hours exercise duration. The percentage of subjects who think supplements have side effects was significantly higher among the supplement non-users than among the users (p < 0 .05). Proteins (83.33%), amino acids (63.09%) and creatine (52.38%) were the most commonly reported supplements used. The places of buying dietary supplements most mentioned were specialized supplement store (78.57%), online (11.9%) and pharmacy (9.52%).

Conclusions

Male fitness club member are large consumers of dietary supplements. Public health campaigns could be useful to educate Serbian population regarding using dietary supplements during fitness activities.

Key messages

Male fitness club members are large consumers of dietary supplements in Serbia. Public health campaigns are needed to educate fitness participants about using dietary supplements.

Roma child participation in public health policy and practice across Europe

Roma teenagers are often excluded from participation opportunities, when they could be informing a wide range of law, policy and practice. CoE and EU recommendations make it clear that improvements in living conditions can only be achieved through active participation of Roma people. The 2018 Roma Civil Society Monitoring report reinforces that 'it is essential for Roma to be involved not only in narrowly defined 'Roma issues', but also in a wider range of topics and policies'. We address the question of what methods enable Roma children to become involved in influencing health policy and service design, focusing on the case of Bulgaria. A qualitative European survey (Feb - June 2020) in English, French, Spanish and Bulgarian identified professional perspectives on the impact of COVID-19 on children, with a focus on Roma families. Case studies of Roma children's experiences, and examples of their participation, were analysed of these case studies was conducted by the authors (combining sociological, public health and community perspectives). Accuracy of emergent findings were assessed through dialogue with survey participants. Preliminary results indicate that participatory practices that enable Roma children's participation in designing public health policy, services and responses are limited and pre-existing inequalities are deepening. However relevant isolated examples of inclusive participation were identified: information design, peer-administered questionnaires, arts-based activities, dialogue events, and campaigning in Bulgaria and beyond. Inclusive methods that enable Roma teenagers' engagement in health policy and service design are closely tied to methods used with other communities facing discrimination. However, significant structural barriers, related to economic inequalities and anti-gypsyism are additional barriers faced by some Roma children. International exchange of examples of such practices could inform future health promotion practice.

Structural basis of transcription inhibition by the DNA mimic protein Ocr of bacteriophage T7

Bacteriophage T7 infects Escherichia coli and evades the host restriction/modification system. The Ocr protein of T7 was shown to exist as a dimer mimicking DNA and to bind to host restriction enzymes, thus preventing the degradation of the viral genome by the host. Here we report that Ocr can also inhibit host transcription by directly binding to bacterial RNA polymerase (RNAP) and competing with the recruitment of RNAP by sigma factors. Using cryo electron microscopy, we determined the structures of Ocr bound to RNAP. The structures show that an Ocr dimer binds to RNAP in the cleft, where key regions of sigma bind and where DNA resides during transcription synthesis, thus providing a structural basis for the transcription inhibition. Our results reveal the versatility of Ocr in interfering with host systems and suggest possible strategies that could be exploited in adopting DNA mimicry as a basis for forming novel antibiotics.

Bacteria and viruses have long been fighting amongst themselves. Bacteriophages are a type of virus that invade bacteria; their name literally means ‘bacteria eater’. The bacteriophage T7, for example, infects the common bacteria known as Escherichia coli. Once inside, the virus hijacks the bacterium’s cellular machinery, using it to replicate its own genetic material and make more copies of the virus so it can spread. At the same time, the bacteria have found ways to try and defend themselves, which in turn has led some bacteriophages to develop countermeasures to overcome those defences.

Many bacteria, for example, have restriction enzymes which recognise certain sections of the bacteriophage DNA and cut it into fragments. However, the T7 bacteriophage has one well-known protein called Ocr which inhibits restriction enzymes. Ocr does this by mimicking DNA, which led Ye et al. to wonder if it could also interrupt other vital processes in a bacterial cell that involve DNA.

Transcription is the first step in a coordinated process that turns the genetic information stored in a cell’s DNA into useful proteins. An enzyme called RNA polymerase decodes the DNA sequence into a go-between molecule called messenger RNA, and it was here that Ye et al. thought Ocr might jump in to interfere.

To begin, Ye et al. examined the structure of Ocr when it binds to RNA polymerase using an imaging technique called cryo-electron microscopy. Ocr has been well-studied before, its structure previously described, but not when attached to RNA polymerase. The analysis showed that Ocr gets in the way of specific molecules, called sigma factors, that show RNA polymerase where to start transcription. Ocr binds to RNA polymerase in exactly the same pocket as part of sigma factors do, which is also the place where DNA must be to be decoded to make messenger RNA. Ye et al. then performed experiments to show Ocr interfering with binding to RNA polymerase did indeed disrupt transcription. This means Ocr is quite versatile as it interferes with the RNA polymerase of the bacterial host and its restriction enzymes.

Ocr’s strategy of mimicking DNA to interrupt transcription could be adopted as an approach to develop new antibiotics to stop bacterial infections. DNA transcription is an essential cellular process – without it, no cell can replicate and survive – and RNA polymerase is already a validated target for drugs. Following Ocr’s lead could provide a new way to stop infections, if the right drug can be designed to fit.

Participation of disadvantaged school age children (7-18) in health inequality projects

Results

The preliminary finding is that none of the ten selected projects have identified children 7-18 years old as a primary target group. Majority of the projects (4 out of 6) involve sort of relationship building with children, while storytelling is used by a smaller number of projects (2 out of 10). All projects (6 out of 6) involve children just in the implementation phase focusing on educating children and none of them in the project design phase. Moreover, children covered by the implementation are mainly included through schools (8 out of 10) due to a missing parent consent for interacting with most disadvantaged children that are not in schools.

Conclusions

There is a serious lack of awareness on the importance of meaningfully engaging disadvantaged children in health programming processes for decreasing existing health inequalities. Due to a significant lack of meaningful participation of disadvantaged children in majority projects tackling health inequalities of school-age children in Europe there is a serious risk of having these inequalities increased rather than overcome, despite significant financial and human investments.

Key messages

The most disadvantaged children should be meaningfully engaged in design, implementation and evaluation of health inequality projects that are of their immediate concern. There is a need for more in depth research on health inequalities faced by school age children (7-18) that are out of educational system.

Mechanisms of σ54-Dependent Transcription Initiation and Regulation

Cellular RNA polymerase is a multi-subunit macromolecular assembly responsible for gene transcription, a highly regulated process conserved from bacteria to humans. In bacteria, sigma factors are employed to mediate gene-specific expression in response to a variety of environmental conditions. The major variant σ factor, σ54, has a specific role in stress responses. Unlike σ70-dependent transcription, which often can spontaneously proceed to initiation, σ54-dependent transcription requires an additional ATPase protein for activation. As a result, structures of a number of distinct functional states during the dynamic process of transcription initiation have been captured using the σ54 system with both x-ray crystallography and cryo electron microscopy, furthering our understanding of σ54-dependent transcription initiation and DNA opening. Comparisons with σ70 and eukaryotic polymerases reveal unique and common features during transcription initiation.

Functional and pharmacological analysis of agmatine administration in different cerebral ischemia animal models

Agmatine (AgM, 100 mg/kg i.p.) effect was tested in parallel at two animal models of cerebral ischemia - rat MCAO model (60'/24 h, 60'/48 h, 90'/24 h, 90'/48 h) and gerbil global ischemia (10') model, administrated 5 min after reperfusion. Aim was to evaluate AgM effect on functional outcome 24 and 48 h after MCAO on neurological and sensor-motor function, and coordination in rats. AgM administration significantly reduced infarct volume, improved neurological score and improved post-ischemic oxidative status. Results of behavioral tests (cylinder test, beam walking test, and adhesive removal test) have shown very effective functional recovery after AgM administration. Efficiency of AgM administration in gerbils was observed in forebrain cortex, striatum, hippocampus, and cerebellum at the level of each examined oxidative stress parameter (nitric oxide level, superoxide production, superoxide dismutase activity, and index of lipid peroxidation) measured in four different time points starting at 3 h up to 48 h after reperfusion. The highest levels were obtained 6 h after the insult. The most sensitive oxidative stress parameter to AgM was nitric oxide. Additionally, we performed pharmacological analysis of AgM on rat isolated common carotid arteries. The findings imply that mixed population of potassium channels located on the smooth muscle cells was involved in common carotid artery response to AgM, with predominance of inward rectifying K⁺ channels. In our comparative experimental approach, judged by behavioral, biochemical, as well as pharmacological data, the AgM administration showed an effective reduction of ischemic neurological damage and oxidative stress, hence indicating a direction towards improving post-stroke recovery.

Surgical treatment of metastasis to the thyroid gland: a single center experience and literature review

BACKGROUND

Metastasis to the thyroid gland or nonthyroid malignancy (NTM) is rarely an indication for thyroidectomy and constitute 1-3 % of all thyroid carcinomas. NTM has a poor prognosis, due to the advanced stage of the primary tumor. This study aimed to present the incidence, clinical characteristics, and treatment outcome of NTM in a single, high volume center.

CASE SERIES

We retrospectively analyzed all patients who had undergone thyroidectomy at the Center for Endocrine Surgery in Belgrade, during the period from 1995 to 2015. Out of 13,385 patients who were submitted to thyroidectomy, 3,344 (24.2 %) patients had thyroid malignancy. The diagnosis of NTM, based on the histopathological findings, was found in ten patients (0.075 % of all patients who had thyroid surgery, i.e., in 0.3 % of patients with thyroid cancer), with a mean age of 59.5 years. The most frequent primary tumor location in NTM was kidney in four patients, esophagus in two patients, and pharynx, breast and lungs (one case each). Total thyroidectomy was performed in four patients and lobectomy in two patients. Mean survival time following thyroid surgery was 43.2 months.

CONCLUSION

NTM are uncommon, and their prognosis is generally poor and depends on the characteristics of the primary tumor. Nevertheless, in selected cases, surgical treatment of NTM should be considered. HIPPOKRATIA 2018, 22(3): 137-140.

Structures of Bacterial RNA Polymerase Complexes Reveal the Mechanism of DNA Loading and Transcription Initiation

Gene transcription is carried out by multi-subunit RNA polymerases (RNAPs). Transcription initiation is a dynamic multi-step process that involves the opening of the double-stranded DNA to form a transcription bubble and delivery of the template strand deep into the RNAP for RNA synthesis. Applying cryoelectron microscopy to a unique transcription system using σ54 (σN), the major bacterial variant sigma factor, we capture a new intermediate state at 4.1 Å where promoter DNA is caught at the entrance of the RNAP cleft. Combining with new structures of the open promoter complex and an initial de novo transcribing complex at 3.4 and 3.7 Å, respectively, our studies reveal the dynamics of DNA loading and mechanism of transcription bubble stabilization that involves coordinated, large-scale conformational changes of the universally conserved features within RNAP and DNA. In addition, our studies reveal a novel mechanism of strand separation by σ54.

ADIPONECTIN AS A POTENTIAL BIOMARKER OF LOW BONE MINERAL DENSITY IN POSTMENOPAUSAL WOMEN WITH METABOLIC SYNDROME

CONTEXT

Adiponectin is an abundant adipokine, which has antiinflammatory, anti-atherosclerotic and vasoprotective actions, and potential antiresorptive effects on bone metabolism. It seems to be directly involved in the improvement and control of energy homeostasis, protecting bone health and predicting osteoporotic fracture risk.

OBJECTIVE

To examine the relationship between adiponectin level and bone mineral density (BMD) in post-menopausal women with metabolic syndrome (MetS) and low BMD, and to estimate the prognostic significance of adiponectin in osteoporosis.

DESIGN

Clinical-laboratory cross-sectional study including 120 middle-aged and elder women (average 69.18±7.56 years).

SUBJECTS AND METHODS

The anthropometric parameters were measured for all examinees. Lumbar spine and hip BMD, as well as body fat percentage, were measured using a Hologic DEXA scanner. In all subjects serum adiponectin concentration was measured by ELISA method.

RESULTS

The level of adiponectin was significantly positively correlated with BMD-total, BMD of the lumbar spine and BMD of the femoral neck (r=0.618, r=0.521, r=0.567; p<0.01). Levels of adiponectin and BMD are significantly lower in post-menopausal women with MetS and osteoporosis compared to patients with osteopenia (856.87±453.43 vs. 1287.32±405.21 pg/mL, p<0.01; BMD, p<0.05), and the highest values in healthy examinees. A cut-off value of adiponectin level for osteoporosis/osteopenia was 1076.22/1392.74 pg/mL.

CONCLUSIONS

Post-menopausal women with MetS have significantly lower adiponectin level and low BMD compared to healthy examinees. Adiponectin may be an early, significant and independent predictor of developing osteoporosis in women with MetS, especially in post-menopausal period.

Oxidative Stress Intensity in Lens and Aqueous Depending on Age-Related Cataract Type and Brunescense

Purpose

Cataract formation represents a serious problem in the elderly, and has a large impact on healthcare budget. The oxidative stress form and intensity might determine the cataract type and pigmentation, making efforts in the cataract prevention challenge more complex.

Methods

This is a retrospective cross-sectional review of 80 samples of aqueous humor and lens corticonuclear blocks. Aqueous samples were analyzed by the method of antioxidant activity estimation (%iMDA), while lipid peroxides (LP) and total sulfhydryl groups (TSH) were determined in lenses.

Results

Mixed and brunescent cataracts have statistically significant lower values of antioxidative %iMDA and TSH (p<0.001 for both parameters) and higher values of lipid peroxidation (p<0.001). No correlation between LP and TSH with maturity of cortical cataract was found, but there was a significant correlation with the %iMDA (p<0.05).

Conclusions

The role of the oxidative stress in cataractogenesis could not be the same for all cataract types. High level of lipid peroxides in pigmented cataracts may point to the different nature of pigment source than proteins solely, whereas lipid peroxidation and SH groups consumption in cortical cataractogenesis might be of less importance.

Functional Characterization of Key Residues in Regulatory Proteins HrpG and HrpV of Pseudomonas syringae pv. tomato DC3000

The plant pathogen Pseudomonas syringae pv. tomato DC3000 uses a type III secretion system (T3SS) to transfer effector proteins into the host. The expression of T3SS proteins is controlled by the HrpL σ factor. Transcription of hrpL is σ⁵⁴-dependent and bacterial enhancer-binding proteins HrpR and HrpS coactivate the hrpL promoter. The HrpV protein imposes negative control upon HrpR and HrpS through direct interaction with HrpS. HrpG interacts with HrpV and relieves such negative control. The sequence alignments across Hrp group I-type plant pathogens revealed conserved HrpV and HrpG amino acids. To establish structure-function relationships in HrpV and HrpG, either truncated or alanine substitution mutants were constructed. Key functional residues in HrpV and HrpG are found within their C-terminal regions. In HrpG, L101 and L105 are indispensable for the ability of HrpG to directly interact with HrpV and suppress HrpV-dependent negative regulation of HrpR and HrpS. In HrpV, L108 and G110 are major determinants for interactions with HrpS and HrpG. We propose that mutually exclusive binding of HrpS and HrpG to the same binding site of HrpV governs a transition from negative control to activation of the HrpRS complex leading to HrpL expression and pathogenicity of P. syringae.

Evading plant immunity: feedback control of the T3SS in Pseudomonas syringae

Microbes are responsible for over 10% of the global yield losses in staple crops such as wheat, rice, and maize. Understanding the decision-making strategies that enable bacterial plant pathogens to evade the host immune system and cause disease is essential for managing their ever growing threat to food security. Many utilise the needle-like type III secretion system (T3SS) to suppress plant immunity, by injecting effector proteins that inhibit eukaryotic signalling pathways into the host cell cytoplasm. Plants can in turn evolve resistance to specific pathogens via recognition and blocking of the T3SS effectors, so leading to an ongoing co-evolutionary 'arms race' between pathogen and host pairs. The extracytoplasmic function sigma factor HrpL co-ordinates the expression of the T3SS regulon in the leaf-dwelling Pseudomonas syringae and similar pathogens. Recently, we showed that association of HrpL with a target promoter directly adjacent to the hrpL gene imposes negative autogenous control on its own expression level due to overlapping regulatory elements. Our results suggest that by down-regulating T3SS function, this fine-tuning mechanism enables P. syringae to minimise effector-mediated elicitation of plant immunity.

The results of molecular genetic testing for RET proto-oncogene mutations in patients with medullary thyroid carcinoma in a referral center after the two decade period

BACKGROUND

Medullary thyroid carcinoma (MTC) is a type of thyroid neoplasm which originates from parafollicular cells, and it is commonly diagnosed by calcitonin screening. Besides the sporadic form, the heritable form of MTC is characterized by constitutive activation of the RET (REarranged during Transfection) proto-oncogene caused by different mutations.

METHOD

We collected data regarding RET genetic screening performed in the Center for Endocrine Surgery in Belgrade during a 20-year-period. The study group included 249 MTC patients who were genetically tested for RET mutations by Sanger's sequencing method.

RESULTS

Genetic screening of the study population revealed nine different mutations of the RET gene in 42 carriers. The most common mutation was C634F, and it has been detected in 31 % (13/42) of individuals, while C618R, L790F, and S904S were present in only 2 % (1/42) each in the study group. Detected mutations were unequally distributed in different RET gene exons. Among MTC patients, 67 % (28/42) had mutation harbored in exon 11, while the rarest mutation was located in exons 10 and 15, each present in only 2 % (1/42) of patients.

CONCLUSIONS

The RET gene mutation profile has a unique distribution in this study population when compared with the other European populations. The mutations in codon 634 are most common; therefore the cost-reducing genetic screening should primarily target this codon, and if the negative outcome appears, then other codons should be examined in the order that depends on their occurrence. Hippokratia 2016, 20(3): 187-191.

Child and Adolescent Online Mental Health Information: Parent and Adolescent Perspectives to Inform Development of Canadian Mental Health E-Resources for Paediatrics

BACKGROUND: Parents and adolescents are searching online for information about mental health. Google searches are frequently used, but do not always yield accurate and reliable information that is presented in a user-friendly manner. The first step toward the development of a useful online child mental health resource is to examine existing web content and understand parent and adolescent needs from online mental health material.

OBJECTIVES: The objectives of this study are two-fold (i) To conduct an environmental scan of existing online repositories of child and adolescent mental health information with respect to both parent and adolescent friendly content on three identified topic areas for the initial phase of the project (Anxiety, Eating Disorders, Suicide Prevention) (ii) To determine parent and adolescent needs from, and perspectives about, current web-based information with respect to site design, content and limitations to inform the creation of a pediatric hospital based web site with a broad range of information pertaining to child and adolescent mental health.

DESIGN/METHODS: An environmental scan was conducted to assess available online information about three identified topic areas as described above. As the project continues, the scan will be expanded to include other topic areas in child and adolescent mental health. Parallel parent needs assessment surveys were conducted. As our adolescent section was being developed, adolescents were surveyed for their feedback regarding illustrations and presentation of current content.

RESULTS: The environmental scan identified 17 hospital websites for in-depth review. Although some websites had information on diverse mental health topics, few contained comprehensive information on a broad range of topics. For example, only 9 had information about anxiety disorders. Additionally, an overall lack of adolescent specific content was noted. Parent surveys revealed significant interest in a strong stand-alone site where they could access mental health information. Parents also indicated that they would prefer separate parent and teen content areas.

CONCLUSION: Current websites providing information regarding child and adolescent mental health, while plentiful, lack sufficient scope, adolescent-friendly content, and interactivity that limit their utility for parents and families. Development of a high-quality and accessible child and adolescent mental health website requires an interdisciplinary collaboration of experts in mental health, website design, and knowledge dissemination. This study has informed the development of a new online resource, interactive elements of which will be shared as part of the oral presentation.

In vitro and in vivo methodologies for studying the Sigma 54-dependent transcription

Here we describe approaches and methods to assaying in vitro the major variant bacterial sigma factor, Sigma 54 (σ(54)), in a purified system. We include the complete transcription system, binding interactions between σ54 and its activators, as well as the self-assembly and the critical ATPase activity of the cognate activators which serve to remodel the closed promoter complexes. We also present in vivo methodologies that are used to study the impact of physiological processes, metabolic states, global signalling networks, and cellular architecture on the control of σ(54)-dependent gene expression.

Interplay among Pseudomonas syringae HrpR, HrpS and HrpV proteins for regulation of the type III secretion system

Pseudomonas syringae pv. tomato DC3000, a plant pathogenic gram-negative bacterium, employs the type III secretion system (T3SS) to cause disease in tomato and Arabidopsis and to induce the hypersensitive response in nonhost plants. The expression of T3SS is regulated by the HrpL extracytoplasmic sigma factor. Expression of HrpL is controlled by transcriptional activators HrpR and HrpS and negative regulator HrpV. In this study, we analysed the organization of HrpRS and HrpV regulatory proteins and interplay between them. We identified one key residue I26 in HrpS required for repression by HrpV. Substitution of I26 in HrpS abolishes its interaction with HrpV and impairs interactions between HrpS and HrpR and the self-association of HrpS. We show that HrpS self-associates and can associate simultaneously with HrpR and HrpV. We now propose that HrpS has a central role in the assembly of the regulatory HrpRSV complex. Deletion analysis of HrpR and HrpS proteins showed that C-terminal parts of HrpR and HrpS confer determinants indispensable for their self-assembly.

Intermittent or continuous occlusion of hepatic inflow

THE AIM OF THE STUDY

The aim was to compare the effects of intermittent and continuous inflow occlusion on liver I/R injury in an experimental model.

METHOD

The experiment was done using the Wistar rats that underwent continuous and intermittent inflow liver vascular occlusion. Blood and liver tissue samples were taken and parameters of hepatic ischemia/reperfusion injury were analyzed and compared.

RESULTS

Serum activities of ALT, AST and LDH were significantly higher and ALP activity and albumin concentration were markedly lower in rats with continuous liver ischemia. Also, histopathological examination revealed more severe changes in animals with continuous liver vascular occlusion.

CONCLUSION

The results of biochemical assay and histopathological examination were concurrent, both indicating more serious parenchymatous damage caused by continuous hepatic pedicle clamping. Study results clearly demonstrated a better tolerance of the liver to intermittent Pringle maneuver (Tab. 1, Fig. 5, Ref. 9).

Advantages of isolated application of fibrin glue over suture in preservation of second-grade spleen lesion

OBJECTIVES

The aim of this procedure was to assess the safety and efficiency of glue application in the treatment of lienal second-degree lesions, compared with traditional suture method of treatment.

BACKGROUND

The spleen is the most frequently injured intra-abdominal structure regardless of injury mechanisms. Fibrin glue is a useful bio-adhesive for safe and efficient treatment of diffuse parenchymatous spleen haemorrhages.

METHODS

Seventy dogs under intravenous anaesthesia were subdued to spleen incision in length of 5 cm and depth of 2 cm. Forty animals from the experimental group were treated with fibrin glue preservation, and 30 animals from the control group were treated with suture. Removed spleens were histologically analyzed. No animal was sacrificed.

RESULTS

The application of fibrin glue allowed reparation to be accomplished in all cases. The effectiveness of primary repair was registered in 95 %, with only 5 % of cases requiring an application of fibrin omentoplasty. Secondary bleeding was registered only in 1 (2.5 %) case. Preservation with suture is primarily effective only in 40 %, requires additional repair in 23 %, and even 37 % of cases are not feasible. This method is characterized by mortality of 21 %, secondary haemorrhage (32 %), appearance of focal necrosis (42 %) and abscess (11 %).

CONCLUSIONS

Application of FG is a method of choice in cases of second-degree transcapsular spleen lesions and it has a considerable advantage over suture (Tab. 4, Fig. 6, Ref. 24).

Prognostic value of survivin expression in Wilms tumor

PURPOSE

To determine survivin expression patterns in Wilms tumor (WT) and compare it with the expression in normal renal tissue. Also, to analyse cytoplasmic and nuclear survivin expression in relation to histological type, prognostic group and tumor stage.

METHODS

Immunohistochemical expression of survivin was analysed in 59 cases of primary WT and in 10 normal kidney specimens, taken from the same patients, but distant from the tumor.

RESULTS

51 out of 59 cases of WT (86.44%) showed decreased cytoplasmic survivin expression and 4 out of 59 cases of WT (6.78%) showed nuclear overexpression of survivin. There was statistically significant difference in the frequency of decreased cytoplasmic expression of survivin in individual components of WT (p=0.005). Decreased cytoplasmic expression of survivin in epithelial, blastemal and stromal component was found significantly more often in low stage WT compared to high stage WT (Fisher exact test, p=0.0002, p=0.002, p=0.002, respectively). There was no statistically significant difference in the frequency of survivin nuclear overexpression between different stages of WT (Fisher exact test, p=0.564), histological types (Fisher exact test, p=0.915), or between different prognostic groups (Fisher exact test, p=1).

CONCLUSION

Decreased survivin cytoplasmic expression or nuclear overexpression may be related to favorable prognosis of WT.

Can the official soccer game be considered the most important contribution to player's physical fitness level?

AIM

During competitive soccer match play, elite players are subdued to vigorous physical and psychological strains. Thus, some changes in overall physical fitness can be expected. The objective of this paper was to determine whether official games influence physical fitness in soccer players.

METHODS

The participants were divided according to the number of minutes spent in the game as well as according to some additional criteria into starters (STA; N.=33, >1000 minutes spent in the official game) and non-starters (NON; N.=31, <1000 minutes spent in the official game). Both groups participated in the initial (end of pre-season) and in the final testing procedures (one week after the end of the competition period). The total of 24 variables covered players' power performance, kicking the ball, aerobic capacity, agility and flexibility.

RESULTS

The STA group showed positive significant differences (P<0.05) from the NON group in 21 out of 24 variables. The most significant findings of this study point to the fact that official games help in maintaining and improving agility parameters (6 out of 7 tests) as well as in maintaining and improving overall power performance of soccer players which includes sprinting, jumping and kicking the ball.

CONCLUSION

Due to specific physiological and psychological factors, official matches make it possible for the starters to develop the mentioned aspects to a higher level when compared to the non-starting team colleagues.

Diagnostic value of the nuclear matrix protein 22 test and urine cytology in upper tract urothelial tumors

OBJECTIVE

To investigate the diagnostic value of the nuclear matrix protein 22 (NMP22) test in comparison to urine cytology for the detection of upper tract urothelial carcinoma.

PATIENTS AND METHODS

Patients with transitional cell carcinoma of the upper urinary tract (n = 34) and patients with renal calculosis (n = 25) were included in this study. Voided urine samples and separated catheter urine specimens were assayed for NMP22 and cytological examination.

RESULTS

The sensitivity of the NMP22 test in separated and voided urine was 73.2 and 70.5%, respectively, compared to 64.7 and 58.8% of urine cytology. The specificity of the NMP22 test in separated and voided urine was 88 and 92%, respectively, compared to 96 and 96% of urine cytology. The combination of separated and voided urine is the best method because the sensitivity is 79.41% and specificity 88%. There is a high agreement of the NMP22 test in voided and separated urine (kappa = 0.795, p < 0.01), indicating that the voided urine is adequate for diagnosis.

CONCLUSIONS

The NMP22 test has higher sensitivity but lower specificity than cytology. The combination of these two tests could be a very useful diagnostic method for detection of upper urothelial tumors.

Activity map of the Escherichia coli RNA polymerase bridge helix

Transcription, the synthesis of RNA from a DNA template, is performed by multisubunit RNA polymerases (RNAPs) in all cellular organisms. The bridge helix (BH) is a distinct feature of all multisubunit RNAPs and makes direct interactions with several active site-associated mobile features implicated in the nucleotide addition cycle and RNA and DNA binding. Because the BH has been captured in both kinked and straight conformations in different crystals structures of RNAP, recently supported by molecular dynamics studies, it has been proposed that cycling between these conformations is an integral part of the nucleotide addition cycle. To further evaluate the role of the BH, we conducted systematic alanine scanning mutagenesis of the Escherichia coli RNAP BH to determine its contributions to activities required for transcription. Combining our data with an atomic model of E. coli RNAP, we suggest that alterations in the interactions between the BH and (i) the trigger loop, (ii) fork loop 2, and (iii) switch 2 can help explain the observed changes in RNAP functionality associated with some of the BH variants. Additionally, we show that extensive defects in E. coli RNAP functionality depend upon a single previously not studied lysine residue (Lys-781) that is strictly conserved in all bacteria. It appears that direct interactions made by the BH with other conserved features of RNAP are lost in some of the E. coli alanine substitution variants, which we infer results in conformational changes in RNAP that modify RNAP functionality.

Regulation of the co-evolved HrpR and HrpS AAA+ proteins required for Pseudomonas syringae pathogenicity

The bacterial AAA+ enhancer-binding proteins (EBPs) HrpR and HrpS (HrpRS) of Pseudomonas syringae (Ps) activate σ⁵⁴-dependent transcription at the hrpL promoter; triggering type-three secretion system-mediated pathogenicity. In contrast with singly acting EBPs, the evolution of the strictly co-operative HrpRS pair raises questions of potential benefits and mechanistic differences this transcription control system offers. Here, we show distinct properties of HrpR and HrpS variants, indicating functional specialization of these non-redundant, tandemly arranged paralogues. Activities of HrpR, HrpS and their control proteins HrpV and HrpG from Ps pv. tomato DC3000 in vitro establish that HrpRS forms a transcriptionally active hetero-hexamer, that there is a direct negative regulatory role for HrpV through specific binding to HrpS and that HrpG suppresses HrpV. The distinct HrpR and HrpS functionalities suggest how partial paralogue degeneration has potentially led to a novel control mechanism for EBPs and indicate subunit-specific roles for EBPs in σ⁵⁴-RNA polymerase activation.

HrpR and HrpS enhancer-binding proteins of Pseudomonas syringae activate σ⁵⁴-dependent transcription of the HrpL promoter and are required for type-three secretion pathogenicity. Here, the authors demonstrate that, despite being co-regulated, HrpR and HrpS each have distinct functions for activating σ⁵⁴.