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Competing Interests: None declared

Background: Nakaseomyces glabrata , formerly Candida glabrata , is an opportunistic yeast and emerging cause of human infections. The use of broth microdilution (BMD) methodologies for caspofungin (CSP) antifungal susceptibility testing (AFST) against N. glabrata is reported to be prone to high inter-laboratory variation. We aimed to compare CSP MICs of N. glabrata isolates from our institution with those obtained by the Reference Laboratory for the same isolates., Methods: All clinically significant N. glabrata isolates from 2019 to 2021 inclusive were reviewed. AFST was performed locally using the VITEK2 system with the AST-YS08 card, while E-tests were performed at the Mycology Reference Laboratory (MRL), and agreement between these two methods was evaluated - categorical and essential., Results: Forty-one isolates were reviewed during the study period - 30 from blood cultures, seven from intra-operative theatre specimens and four from sterile site drain fluids. Despite an essential agreement of 100 % within ±2 log 2 dilutions, marked discrepancies were noted in interpretative breakpoints between assays with 17 Minor and 16 Major category errors. Categorical agreement was 19.5 %, with the VITEK2 over-estimating resistance. A Mann-Whitney U-test assessed the relationship of MICs across the AFST modalities, and a statistically significant difference was noted, P <0.01, with a higher mean rank for VITKEK2 outputs., Conclusion: While the VITEK2 system is highly applicable, its performance for CSP AFST is unreliable and potentially results in the mis-classification of susceptible isolates as highlighted in our study. The use of VITEK2 AST-YS08 micafungin as a sentinel echinocandin should be explored and/or the evaluation of CSP-specific E-tests as utilized by the MRL. These methods appear more consistent and less prone to the variation seen with BMD for CSP., Competing Interests: The authors declare that there are no conflicts of interest., (© 2023 The Authors.)

In late 2020, the results of CASP14, the 14th event in a series of competitions to assess the latest developments in computational protein structure-prediction methodology, revealed the giant leap forward that had been made by Google's Deepmind in tackling the prediction problem. The level of accuracy in their predictions was the first instance of a competitor achieving a global distance test score of better than 90 across all categories of difficulty. This achievement represents both a challenge and an opportunity for the field of experimental structural biology. For structure determination by macromolecular X-ray crystallography, access to highly accurate structure predictions is of great benefit, particularly when it comes to solving the phase problem. Here, details of new utilities and enhanced applications in the CCP4 suite, designed to allow users to exploit predicted models in determining macromolecular structures from X-ray diffraction data, are presented. The focus is mainly on applications that can be used to solve the phase problem through molecular replacement., (open access.)

Nowadays, progress in the determination of three-dimensional macromolecular structures from diffraction images is achieved partly at the cost of increasing data volumes. This is due to the deployment of modern high-speed, high-resolution detectors, the increased complexity and variety of crystallographic software, the use of extensive databases and high-performance computing. This limits what can be accomplished with personal, offline, computing equipment in terms of both productivity and maintainability. There is also an issue of long-term data maintenance and availability of structure-solution projects as the links between experimental observations and the final results deposited in the PDB. In this article, CCP4 Cloud, a new front-end of the CCP4 software suite, is presented which mitigates these effects by providing an online, cloud-based environment for crystallographic computation. CCP4 Cloud was developed for the efficient delivery of computing power, database services and seamless integration with web resources. It provides a rich graphical user interface that allows project sharing and long-term storage for structure-solution projects, and can be linked to data-producing facilities. The system is distributed with the CCP4 software suite version 7.1 and higher, and an online publicly available instance of CCP4 Cloud is provided by CCP4., (open access.)

Introduction: The need to improve the quality of community mental health services for people with Complex Emotional Needs (CEN) (who may have a diagnosis of 'personality disorder') is recognised internationally and has become a renewed policy priority in England. Such improvement requires positive engagement from clinicians across the service system, and their perspectives on achieving good practice need to be understood., Aim: To synthesise qualitative evidence on clinician perspectives on what constitutes good practice, and what helps or prevents it being achieved, in community mental health services for people with CEN., Methods: Six bibliographic databases were searched for studies published since 2003 and supplementary citation tracking was conducted. Studies that used any recognised qualitative method and reported clinician experiences and perspectives on community-based mental health services for adults with CEN were eligible for this review, including generic and specialist settings. Meta-synthesis was used to generate and synthesise over-arching themes across included studies., Results: Twenty-nine papers were eligible for inclusion, most with samples given a 'personality disorder' diagnosis. Six over-arching themes were identified: 1. The use and misuse of diagnosis; 2. The patient journey into services: nowhere to go; 3. Therapeutic relationships: connection and distance; 4. The nature of treatment: not doing too much or too little; 5. Managing safety issues and crises: being measured and proactive; 6. Clinician and wider service needs: whose needs are they anyway? The overall quality of the evidence was moderate., Discussion: Through summarising the literature on clinician perspectives on good practice for people with CEN, over-arching priorities were identified on which there appears to be substantial consensus. In their focus on needs such as for a long-term perspective on treatment journeys, high quality and consistent therapeutic relationships, and a balanced approach to safety, clinician priorities are mainly congruent with those found in studies on service user views. They also identify clinician needs that should be met for good care to be provided, including for supervision, joint working and organisational support., Competing Interests: The authors have declared that no competing interests exist.

Objectives: In recent years various clinical studies have demonstrated poor outcomes in infections caused by anaerobic bacteria due to inappropriate therapy, directly due to emergence of resistant strains. This is a concern given that many anaerobic infections are treated empirically with metronidazole or a beta-lactam/beta-lactamase inhibitor combinations (e.g., co-amoxiclav, piperacillin-tazobactam). To date there is a paucity of available data on antimicrobial resistance trends of anaerobic bacteria in Ireland, and our study aims to determine such patterns among isolates processed at our institution over the last ten years., Methods: Significant anaerobic bacteria isolated from clinical specimens processed at our laboratory from January 2010 to January 2020 inclusive were reviewed. Bacteria were identified using MALDI-TOF, with E-tests used for antimicrobial susceptibility testing. Data was processed through WHONET., Results: A total of 2098 clinically significant anaerobic bacterial isolates from blood cultures (31%), theatre/intraoperative specimens (30%), aspirates and drain fluid (22%) and wound swabs (17%) were reviewed during the study period; with the majority of isolates being Bacteroides spp (32.79%, n = 688) and Clostridium spp (18.68%, n = 392). With isolates demonstrating well-recognised or inherent resistances excluded, overall resistance to tested antimicrobials was 6.40% to penicillin, 1.71% to metronidazole, 1.43% to co-amoxiclav, 13.63% to clindamycin, 0.43% to piperacillin-tazobactam and 0% to meropenem., Conclusion: Metronidazole and beta-lactam/beta-lactamase inhibitor combinations remain highly efficacious against the majority of anaerobic isolates reviewed, and can safely be used as empiric therapy in suspected anaerobic infections. However, periodic surveillance of resistance trends remains important., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Individuals with Complex Emotional Needs (CEN) services, a working description to refer to the needs experienced by people who may have been diagnosed with a "personality disorder", face premature mortality, high rates of co-morbidity, service user and treatment costs. Service provision for this population is recurrently identified as needing to be transformed: there are serious concerns about quality, accessibility, fragmentation of the service system and the stigma and therapeutic pessimism service users encounter. Understanding clinician perspectives is vital for service transformation, as their views and experiences shed light on potential barriers to achieving good care, and how these might be overcome. In this study, we aimed to explore these views., Methods: We used a qualitative interview design. A total of fifty participants from a range of professions across specialist and generic community mental health services across England who provide care to people with CEN took part in six focus groups and sixteen one-to-one interviews. We analysed the data using a thematic approach., Findings: Main themes were: 1) Acknowledging the heterogeneity of needs: the need for a person-centred care approach and flexibility when working with CEN, 2) 'Still a diagnosis of exclusion': Exploring the healthcare provider-level barriers to providing care, and 3) Understanding the exclusionary culture: exploring the system-based barriers to providing care for CEN. Across these themes, staff highlighted in particular the need for care that was person-centred, relational, empathic, and trauma informed. Major barriers to achieving this are stigmatising attitudes and behaviour towards people with CEN, especially in generic mental health services, lack of development of coherent service systems offering clear long-term pathways and ready access to high quality treatment, and lack of well-developed structures for staff training and support., Discussion: Overall, the findings point towards clinician views as generally congruent with those of service users, reinforcing the need for priorities towards systemwide change to ensure that best practice care is provided for people with CEN. Particularly prominent is the need to put in place systemwide training and support for clinicians working with CEN, encompassing generic and specialist services, and to challenge the stigma still experienced throughout the system., Conclusions: Staff working with this service user group report that delivering best practice care requires services to be flexible, integrated, and sustainably funded, and for staff to be supported through ongoing training and supervision., (© 2022. The Author(s).)

Background: There is consensus that services supporting people with complex emotional needs are part of a mental health care system in which change is needed. To date, service users' views and co-production initiatives have had little impact on the development of interventions and care. This needs to change, and our paper evidences the experiences and perspectives of a diverse range of people on how community services can best address the needs of people with complex emotional needs., Methods: A co-produced qualitative research study. Lived experience researchers led data collection and analysis. Individual interviews were conducted with 30 people across England who had a diverse range of experiences and perspectives of using community services for complex emotional needs. Participants were asked about their experiences of using community services for their mental health, and views on how community services can best address their needs. Thematic analysis was used to analyse the data., Results: Participants reported some experiences of good practice but also of experiences of severely stigmatising interventions, a lack of effective support and service fragmentation. Relational Practice was identified as the central overarching theme and describes how community services can best support people with complex emotional needs. This approach involves care delivered in a non-stigmatising, individualised and compassionate way and care that is trauma-informed. It involves care that is planned collaboratively with service users to ensure their multiple needs are addressed in a flexible, holistic and consistent way which accounts for the long-term and fluctuating nature of their needs., Conclusions: Relational practice approaches have potential to facilitate better community care for people with complex emotional needs. Research and service development are needed to examine how best to implement such approaches across the mental health service system. This work must be co-produced with people with relevant lived experience, their carers and the professionals who support them., (© 2022. The Author(s).)

The radiation-attenuated cercarial vaccine remains the gold standard for the induction of protective immunity against Schistosoma mansoni . Furthermore, the protection can be passively transferred to naïve recipient mice from multiply vaccinated donors, especially IFNgR KO mice. We have used such sera versus day 28 infection serum, to screen peptide arrays and identify likely epitopes that mediate the protection. The arrays encompassed 55 secreted or exposed proteins from the alimentary tract and tegument, the principal interfaces with the host bloodstream. The proteins were printed onto glass slides as overlapping 15mer peptides, reacted with primary and secondary antibodies, and reactive regions detected using an Agilent array scanner. Pep Slide Analyzer software provided a numerical value above background for each peptide from which an aggregate score could be derived for a putative epitope. The reactive regions of 26 proteins were mapped onto crystal structures using the CCP4 molecular graphics, to aid selection of peptides with the greatest accessibility and reactivity, prioritizing vaccine over infection serum. A further eight MEG proteins were mapped to regions conserved between family members. The result is a list of priority peptides from 44 proteins for further investigation in multiepitope vaccine constructs and as targets of monoclonal antibodies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Farias, Vance, Coulson, Vitoriano-Souza, Neto, Wangwiwatsin, Neves, Castro-Borges, McNicholas, Wilson, Leite and Wilson.)

Background: Rehabilitation facilities have among the highest prevalence of multidrug-resistant organism (MDRO) colonization of any inpatient population. There is no formal consensus on how patients with MDROs should be managed in the rehabilitation setting., Aim: The aim of this study was to assess how rehabilitation hospitals throughout Europe manage patients with MDROs, and the impact of MDRO carriage on outcomes., Design: Cross-sectional study., Setting: Online questionnaire distributed to European rehabilitation facilities., Population: European rehabilitation facilities., Methods: A Survey Monkey® questionnaire was designed and circulated to rehabilitation hospitals via the European Union of Medical Specialists, Physical and Rehabilitation Medicine Section., Results: Fifty-four responses were received of which 45 were suitable for analysis. Six out of 26 (23%) countries included in the study reported at least one rehabilitation facility with an estimated MDRO prevalence rate of 31% or higher. Screening of all patients on admission was always carried out in 33% (15 of 45) of facilities. Twenty-five of the 45 facilities (69%), aim to isolate, or cohort patients who have MDROs. Patients with MDROs wait longer for admission (36%, 16 of 45) and in the case of five hospitals admission is refused. Fifty-one percent (23 of 45) of facilities reported that colonization with an MDRO severely or moderately limits rehabilitation outcome., Conclusions: Our research shows that many of the challenges posed by MDROs are common to facilities throughout Europe. We strongly recommend that all patients are screened for MDROs on admission. We stress that any negative impact of a patients MDRO status on their rehabilitation outcome must be minimized., Clinical Rehabilitation Impact: Specific guidance on the management of rehabilitation patients with MDROs, would allow them to partake in a full rehabilitation program, while limiting the spread of MDROs.

Scripting programming languages provide the fastest means of prototyping complex functionality. Those with a syntax and grammar resembling human language also greatly enhance the maintainability of the produced source code. Furthermore, the combination of a powerful, machine-independent scripting language with binary libraries tailored for each computer architecture allows programs to break free from the tight boundaries of efficiency traditionally associated with scripts. In the present work, we describe how an efficient C++ crystallographic library such as Clipper can be wrapped, adapted and generalized for use in both crystallographic and electron cryo-microscopy applications, scripted with the Python language. We shall also place an emphasis on best practices in automation, illustrating how this can be achieved with this new Python module., (© 2017 The Authors Protein Science published by Wiley Periodicals, Inc. on behalf of The Protein Society.)

The close-range interactions provided by covalently linked glycans are essential for the correct folding of glycoproteins and also play a pivotal role in recognition processes. Being able to visualise protein-glycan and glycan-glycan contacts in a clear way is thus of great importance for the understanding of these biological processes. In structural terms, glycosylation sugars glue the protein together via hydrogen bonds, whereas non-covalently bound glycans frequently harness additional stacking interactions. Finding an unobscured molecular view of these multipartite scenarios is usually far from trivial; in addition to the need to show the interacting protein residues, glycans may contain many branched sugars, each composed of more than ten non-H atoms and offering more than three potential bonding partners. With structural glycoscience finally gaining popularity and steadily increasing the deposition rate of three-dimensional structures of glycoproteins, the need for a clear way of depicting these interactions is more pressing than ever. Here a schematic representation, named Glycoblocks, is introduced which combines a simplified bonding-network depiction (covering hydrogen bonds and stacking interactions) with the familiar two-dimensional glycan notation used by the glycobiology community, brought into three dimensions by the CCP4 molecular graphics project (CCP4mg).

Patients with end-stage renal failure undergo regular haemodialysis (HD) and often develop episodes of Staphylococcus aureus bloodstream infection (BSI), which can re-occur. However, clinically, patients on HD, with S. aureus BSI, respond well to treatment, rarely developing overt signs of sepsis. We investigated the contributions of bacterial virulence and cytokine responses to the clinical course of S. aureus BSI in HD and non-HD patients. Seventy patients were recruited, including 27 (38.6 %) patients on HD. Isolates were spa-typed and virulence and antimicrobial resistance gene carriage was investigated using DNA microarray analysis. Four inflammatory cytokines, IL-6, RANTES, GROγ and leptin, were measured in patient plasma on the day of diagnosis and after 7 days. There was no significant difference in the prevalence of genotypes or antimicrobial resistance genes in S. aureus isolates from HD compared to non-HD patients. The enterotoxin gene cluster (containing staphylococcal enterotoxins seg, sei, sem, sen, seo and seu) was significantly less prevalent among BSI isolates from HD patients compared to non-HD patients. Comparing inflammatory cytokine response to S. aureus BSI in HD patients to non-HD patients, IL-6 and GROγ were significantly lower (p = 0.021 and p = 0.001, respectively) in HD patients compared to other patients on the day of diagnosis and RANTES levels were significantly lower (p = 0.025) in HD patients on day 7 following diagnosis. Lowered cytokine responses in HD patients and a reduced potential for super-antigen production by infecting isolates may partly explain the favourable clinical responses to episodes of S. aureus BSI in HD patients that we noted clinically.

The industrial conversion of cellulosic plant biomass into useful products such as biofuels is a major societal goal. These technologies harness diverse plant degrading enzymes, classical exo- and endo-acting cellulases and, increasingly, cellulose-active lytic polysaccharide monooxygenases, to deconstruct the recalcitrant β-D-linked polysaccharide. A major drawback with this process is that the exo-acting cellobiohydrolases suffer from severe inhibition from their cellobiose product. β-D-Glucosidases are therefore important for liberating glucose from cellobiose and thereby relieving limiting product inhibition. Here, the three-dimensional structures of two industrially important family GH3 β-D-glucosidases from Aspergillus fumigatus and A. oryzae, solved by molecular replacement and refined at 1.95 Å resolution, are reported. Both enzymes, which share 78% sequence identity, display a three-domain structure with the catalytic domain at the interface, as originally shown for barley β-D-glucan exohydrolase, the first three-dimensional structure solved from glycoside hydrolase family GH3. Both enzymes show extensive N-glycosylation, with only a few external sites being truncated to a single GlcNAc molecule. Those glycans N-linked to the core of the structure are identified purely as high-mannose trees, and establish multiple hydrogen bonds between their sugar components and adjacent protein side chains. The extensive glycans pose special problems for crystallographic refinement, and new techniques and protocols were developed especially for this work. These protocols ensured that all of the D-pyranosides in the glycosylation trees were modelled in the preferred minimum-energy (4)C1 chair conformation and should be of general application to refinements of other crystal structures containing O- or N-glycosylation. The Aspergillus GH3 structures, in light of other recent three-dimensional structures, provide insight into fungal β-D-glucosidases and provide a platform on which to inform and inspire new generations of variant enzymes for industrial application.

Background: The clinical course of Staphylococcus aureus bloodstream infection is unpredictable and bacterial virulence, host immune response and patient characteristics are among the factors that contribute to the clinical course of infection. To investigate the relationship between cytokine response and clinical outcome, circulating cytokine levels were investigated in response to S. aureus bloodstream infection in patients with different clinical courses of infection., Methods: A prospective study was carried out in 61 patients with S. aureus bloodstream infection and circulating levels of IL-6, GRO-γ, RANTES and leptin were assessed over the course of the infection. Levels were compared in patients with complicated courses of infection (e.g. infective endocarditis) versus uncomplicated courses of S. aureus bloodstream infection and methicillin-resistant S. aureus Vs methicillin-susceptible S. aureus infection., Results: Significantly lower leptin levels (p < 0.05) and significantly higher IL-6 levels (p < 0.05) were detected at laboratory diagnosis in patients with complicated compared to uncomplicated S. aureus bloodstream infection. Significantly higher levels of GRO-γ were associated with MRSA infection compared to MSSA infection., Conclusions: IL-6 may be an early inflammatory marker of complicated S. aureus bloodstream infection. Leptin may be protective against the development of a complicated S. aureus bloodstream infection.

The identification and exploration of (dis)similarities between macromolecular structures can help to gain biological insight, for instance when visualizing or quantifying the response of a protein to ligand binding. Obtaining a residue alignment between compared structures is often a prerequisite for such comparative analysis. If the conformational change of the protein is dramatic, conventional alignment methods may struggle to provide an intuitive solution for straightforward analysis. To make such analyses more accessible, the Procrustes Structural Matching Alignment and Restraints Tool (ProSMART) has been developed, which achieves a conformation-independent structural alignment, as well as providing such additional functionalities as the generation of restraints for use in the refinement of macromolecular models. Sensible comparison of protein (or DNA/RNA) structures in the presence of conformational changes is achieved by enforcing neither chain nor domain rigidity. The visualization of results is facilitated by popular molecular-graphics software such as CCP4mg and PyMOL, providing intuitive feedback regarding structural conservation and subtle dissimilarities between close homologues that can otherwise be hard to identify. Automatically generated colour schemes corresponding to various residue-based scores are provided, which allow the assessment of the conservation of backbone and side-chain conformations relative to the local coordinate frame. Structural comparison tools such as ProSMART can help to break the complexity that accompanies the constantly growing pool of structural data into a more readily accessible form, potentially offering biological insight or influencing subsequent experiments.

We present the case of an immunocompetent male who presented with symptoms of meningitis. Yeasts were seen in two consecutive cerebrospinal fluid samples, which were identified by PCR as Sporobolomyces roseus. This yeast is rarely encountered in clinical settings, and has only previously been seen to cause infection in immunocompromised patients. This case highlights the challenges presented by the identification of an unusual pathogen in an unexpected clinical setting.

Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29/36 (80%) and 33/36 (92%) isolates, respectively.

CCP4mg is a molecular-graphics program that is designed to give rapid access to both straightforward and complex static and dynamic representations of macromolecular structures. It has recently been updated with a new interface that provides more sophisticated atom-selection options and a wizard to facilitate the generation of complex scenes. These scenes may contain a mixture of coordinate-derived and abstract graphical objects, including text objects, arbitrary vectors, geometric objects and imported images, which can enhance a picture and eliminate the need for subsequent editing. Scene descriptions can be saved to file and transferred to other molecules. Here, the substantially enhanced version 2 of the program, with a new underlying GUI toolkit, is described. A built-in rendering module produces publication-quality images.

Background: Women's crisis houses have been developed in the UK as a less stigmatising and less institutional alternative to traditional psychiatric wards., Aims: To examine the effectiveness and cost-effectiveness of women's crisis houses by first examining the feasibility of a pilot patient-preference randomised controlled trial (PP-RCT) design (ISRCTN20804014)., Method: We used a PP-RCT study design to investigate women presenting in crisis needing informal admission. The four study arms were the patient preference arms of women's crisis house or hospital admission, and randomised arms of women's crisis house or hospital admission., Results: Forty-one women entered the randomised arms of the trial (crisis house n = 19, wards n = 22) and 61 entered the patient-preference arms (crisis house n = 37, ward n = 24). There was no significant difference in outcomes (symptoms, functioning, perceived coercion, stigma, unmet needs or quality of life) or costs for any of the groups (randomised or preference arms), but women who obtained their preferred intervention were more satisfied with treatment., Conclusions: Although the sample sizes were too small to allow definite conclusions, the results suggest that when services are able to provide interventions preferred by patients, those patients are more likely to be satisfied with treatment. This pilot study provides some evidence that women's crisis houses are as effective as traditional psychiatric wards, and may be more cost-effective.

Amphiphilic beta-cyclodextrins have been synthesized bearing hexylthio, dodecylthio, and hexadecylthio chains at the 6-positions and glycosylthiocarbamoyl-oligo(ethylene glycol) units at the 2-positions. The glycosyl residues (alpha-D-mannosyl and beta-L-fucosyl) are intended for cell-targeting. Self-assembly of these new amphiphilic glycosylated cyclodextrins in water to form vesicles was investigated by dynamic light scattering and transmission electron microscopy. Selective binding of the hexylthio assemblies to a protein receptor (Lens culinaris lectin) was confirmed by fluorescence spectroscopy.

Progress towards structure determination that is both high-throughput and high-value is dependent on the development of integrated and automatic tools for electron-density map interpretation and for the analysis of the resulting atomic models. Advances in map-interpretation algorithms are extending the resolution regime in which fully automatic tools can work reliably, but at present human intervention is required to interpret poor regions of macromolecular electron density, particularly where crystallographic data is only available to modest resolution [for example, I/sigma(I) < 2.0 for minimum resolution 2.5 A]. In such cases, a set of manual and semi-manual model-building molecular-graphics tools is needed. At the same time, converting the knowledge encapsulated in a molecular structure into understanding is dependent upon visualization tools, which must be able to communicate that understanding to others by means of both static and dynamic representations. CCP4 mg is a program designed to meet these needs in a way that is closely integrated with the ongoing development of CCP4 as a program suite suitable for both low- and high-intervention computational structural biology. As well as providing a carefully designed user interface to advanced algorithms of model building and analysis, CCP4 mg is intended to present a graphical toolkit to developers of novel algorithms in these fields.

One of the most important aspects of macromolecular structure refinement is the use of prior chemical knowledge. Bond lengths, bond angles and other chemical properties are used in restrained refinement as subsidiary conditions. This contribution describes the organization and some aspects of the use of the flexible and human/machine-readable dictionary of prior chemical knowledge used by the maximum-likelihood macromolecular-refinement program REFMAC5. The dictionary stores information about monomers which represent the constitutive building blocks of biological macromolecules (amino acids, nucleic acids and saccharides) and about numerous organic/inorganic compounds commonly found in macromolecular crystallography. It also describes the modifications the building blocks undergo as a result of chemical reactions and the links required for polymer formation. More than 2000 monomer entries, 100 modification entries and 200 link entries are currently available. Algorithms and tools for updating and adding new entries to the dictionary have also been developed and are presented here. In many cases, the REFMAC5 dictionary allows entirely automatic generation of restraints within REFMAC5 refinement runs.

This new package will provide easy-to-use access to crystallographic structure solution, model building and structure analysis. It will be possible for any developer to integrate scientific software into the system.

Adequate use of local anesthetics is an important phase of modern dentistry. Regardless of the care used in administration of local anesthetics, unusual reactions can occur. A case is presented in which posterior superior alveolar administration of two percent Lidocaine 1/100,000 epinephrine resulted in medial rotation of the orbit (esotropia).

Prostaglandins (PG) have been implicated in the genesis of periapical lesions. Periapical specimens from patients with clinical signs and symptoms of chronic and acute apical periodontitis were obtained and immediately frozen in liquid nitrogen. Periradicular tissues from unerupted third molars were frozen and used as controls. The concentration of PGE2 was determined by radioimmunoassay. Low levels of PGE2 were found in the control tissues as compared with those detected in chronic and acute lesions. Significantly higher levels of PGE2 were found in acute lesions than those found in chronic lesions. The results show that acute lesions have higher concentrations of PGE2 than chronic lesions and confirm the role of prostaglandins in the pathogenesis of human periapical lesions.