Identifizierung pathogenitätsrelevanter Gene in Candida albicans und Candida dubliniensis

C. albicans ist das häufigste Erregerisolat aus Candidämiepatienten, deren Krankheitsverlauf mit hohen Mortalitätsraten verknüpft ist. In unterschiedlichen Risikogruppen steigt die Wichtigkeit von nicht-albicans Candidosen, so tritt in HIV-seropositiven Patienten Candida dubliniensis häufig in Mischkulturen auf. Obwohl C. dubliniensis der nächste Verwandte von C. albicans und ihre Genetik sehr ähnlich ist, unterscheidet sich er durch seine verminderte Pathogenität. Der Anspruch der vorliegenden Arbeit war der zwischenartliche genetische und phänotypische Vergleich von C. albicans und C. dubliniensis zur Identifikation und Charakterisierung verschiedenartiger virulenzassoziierter Faktoren. Die Bildung von Chlamydosporen als morphologische Struktur ist ein Mittel der klinischen Diagnostik, doch sind sowohl ihre biologische Funktionen als auch die Mechanismen zur molekulargenetischen Regulation weitestgehend unbekannt. Besonderen Regulatoren der Hyphenbildung auch in diesem morphologischen Prozess involviert. Die Initiation der Chlamydosporulation konnte als Hungerantwort kategorisiert werden, die sich durch speziesspezifische Schwellenwerte des Nährstofflimits darstellte und über den Repressor Nrg1 vermittelt wurde. Im Zusammenhang der nährstoffgetriebenen Entwicklungsprozesse konnte die C. dubliniensis-spezifische Chlamydosporen- und Pseudohyphenbildung auf Stickstoffmangelmedium durch die Integration des C. albicans Gens, HMA1 (orf19.2115), zu einem Hefenwachstum verschoben werden. Hma1-negative C. albicans und C. dubliniensis-Mutanten zeigten Veränderungen in ihrer Rapamycinresistenz. Eine deutliche Verkürzung der Filamente trat nur in den C. albicans hma1/-Mutanten auf, die auf oralen Zellen mit einer verminderten Adhärenz und Invasivität korrelierte und in der Attenuierung im Infektionsmodell mündete. Mittels Analysen von orthologen Faktoren konnte C. albicans Hma1 als Threonylcarbamoyladenosin-Dehydratase klassifiziert werden und direkt die Effizienz und Leserahmengenauigkeit der Translation verstärkt. Resümierend konnte hier erstmals die exakte Komposition von tRNA-Basenmodifikationen als ein vollkommen neuartiger, epigenetischer Pathogenitätsmechanismus für pilzliche Humanpathogene beschrieben werden

Packaging of up to 240 subunits of a 17 kDa nuclease into the interior of recombinant hepatitis B virus capsids

AbstractThe icosahedral nucleocapsid of hepatitis B virus (HBV) consists of multiple subunits of a single 183 amino acids (aa) core protein encasing the viral genome. However, recombinant core protein alone also forms capsid-like particles. We have recently shown that a 238 aa protein centrally inserted into the core protein can be displayed on the particle surface. Here we demonstrate that replacement of the C-terminal basic domain by the 17 kDa Staphylococcus aureus nuclease also yields particles but that in these the foreign domains are located in the interior. The packaged nuclease is enzymatically active, and the chimeric protein forms mosaic particles with the wild-type core protein. Hence the HBV capsid is useful as a molecular platform which, dependent on the fusion site, allows foreign protein domains to either be packaged into or be exposed on the exterior of the particle. These results are of relevance for the use of the HBV capsid as a vaccine carrier, and as a target for antiviral therapy

Inpatient management of community-acquired pneumonia at the European Gaza Hospital: a clinical audit

Background Disease severity scores such as CURB-65 are often used to guide the management of patients with community-acquired pneumonia. Early and adequate empirical antibiotic treatment reduces mortality. The aim of this study was to examine the severity assessment and management of patients presenting with community-acquired pneumonia at the European Gaza Hospital in the Gaza Strip and to compare this to the best available evidence. Methods Medical records of all patients admitted to the European Gaza Hospital with a diagnosis of community-acquired pneumonia between Dec 1, 2015, and March 31, 2016, were reviewed retrospectively. Clinical practice was compared with recommendations for severity assessment and the management of community-acquired pneumonia, as reported in guidelines by the National Institute for Health and Care Excellence and the American Thoracic Society

Hepatitis B virus core protein phosphorylation: Identification of the SRPK1 target sites and impact of their occupancy on RNA binding and capsid structure

International audienceHepatitis B virus (HBV) replicates its 3 kb DNA genome through capsid-internal reverse transcription, initiated by assembly of 120 core protein (HBc) dimers around a complex of viral pregenomic (pg) RNA and polymerase. Following synthesis of relaxed circular (RC) DNA capsids can be enveloped and secreted as stable virions. Upon infection of a new cell, however, the capsid disintegrates to release the RC-DNA into the nucleus for conversion into covalently closed circular (ccc) DNA. HBc´s interactions with nucleic acids are mediated by an arginine-rich C terminal domain (CTD) with intrinsically strong non-specific RNA binding activity. Adaptation to the changing demands for nucleic acid binding during the viral life cycle is thought to involve dynamic phosphorylation / dephosphorylation events. However, neither the relevant enzymes nor their target sites in HBc are firmly established. Here we developed a bacterial coexpression system enabling access to definably phosphorylated HBc. Combining Phos-tag gel electrophoresis, mass spectrometry and mutagenesis we identified seven of the eight hydroxy amino acids in the CTD as target sites for serine-argi-nine rich protein kinase 1 (SRPK1); fewer sites were phosphorylated by PKA and PKC. Phosphorylation of all seven sites reduced nonspecific RNA encapsidation as drastically as deletion of the entire CTD and altered CTD surface accessibility, without major structure changes in the capsid shell. The bulk of capsids from human hepatoma cells was similarly highly, yet non-identically, phosphorylated as by SRPK1. While not proving SRPK1 as the infection-relevant HBc kinase the data suggest a mechanism whereby high-level HBc phos-phorylation principally suppresses RNA binding whereas one or few strategic dephosphory-lation events enable selective packaging of the pgRNA/polymerase complex. The tools developed in this study should greatly facilitate the further deciphering of the role of HBc phosphorylation in HBV infection and its evaluation as a potential new therapeutic target. PLOS Pathogens | https://doi.org/10.1371/journal.ppat

Maternal mortality in the Gaza strip: a look at causes and solutions

Background: Maternal mortality is an important health indicator for the overall health of a population. This study assessed the causes and contributing factors to maternal mortality that occurred in the Gaza-Strip between July 2014 and June 2015. Methods: This is a retrospective study that used both quantitative and qualitative data. The data were collected from available medical records, investigation reports, death certificates, and field interviews with healthcare professionals as well as families. Results: A total of 18 maternal mortalities occurred in Gaza between 1st July 2014 and June 30th 2015. Age at time of death ranged from 18 to 44 years, with 44.4% occurring before the age of 35 years. About 22.2% were primiparous, while 55.6% were grand multiparous women. The most common causes of death were sepsis, postpartum haemorrhage, and pulmonary embolism. The most striking deficiency was very poor medical documentation which was observed in 17 cases (94%). In addition, poor communication between doctors and women and their families or among healthcare teams was noticed in nine cases (50%). These were repeatedly described by families during interviews. Further aspects surfacing in many interviews were distrust by families towards clinicians and poor understanding of health conditions by women. Other factors included socioeconomic conditions, poor antenatal attendance and the impact of the 2014 war. Low morale among medical staff was expressed by most interviewed clinicians, as well as the fear of being blamed by families and management in case of adverse events. Substandard care and lack of appropriate supervision were also found in some cases. Conclusions: This study revealed deficiencies in maternity care, some of which were linked to the socioeconomic situation and the 2014 war. Others show poor implementation of clinical guidelines and lack of professional skills in communication and teamwork. Specialised training should be offered for clinicians in order to improve these aspects. However, the most striking deficiency was the extremely poor documentation, reflecting a lack of awareness among clinicians regarding its importance. Local policymakers should focus on systematic application of quality improvement strategies in order to achieve greater patient safety and further reductions in the maternal mortality rate.Background: Maternal mortality is an important health indicator for the overall health of a population. This study assessed the causes and contributing factors to maternal mortality that occurred in the Gaza-Strip between July 2014 and June 2015. Methods: This is a retrospective study that used both quantitative and qualitative data. The data were collected from available medical records, investigation reports, death certificates, and field interviews with healthcare professionals as well as families. Results: A total of 18 maternal mortalities occurred in Gaza between 1st July 2014 and June 30th 2015. Age at time of death ranged from 18 to 44 years, with 44.4% occurring before the age of 35 years. About 22.2% were primiparous, while 55.6% were grand multiparous women. The most common causes of death were sepsis, postpartum haemorrhage, and pulmonary embolism. The most striking deficiency was very poor medical documentation which was observed in 17 cases (94%). In addition, poor communication between doctors and women and their families or among healthcare teams was noticed in nine cases (50%). These were repeatedly described by families during interviews. Further aspects surfacing in many interviews were distrust by families towards clinicians and poor understanding of health conditions by women. Other factors included socioeconomic conditions, poor antenatal attendance and the impact of the 2014 war. Low morale among medical staff was expressed by most interviewed clinicians, as well as the fear of being blamed by families and management in case of adverse events. Substandard care and lack of appropriate supervision were also found in some cases. Conclusions: This study revealed deficiencies in maternity care, some of which were linked to the socioeconomic situation and the 2014 war. Others show poor implementation of clinical guidelines and lack of professional skills in communication and teamwork. Specialised training should be offered for clinicians in order to improve these aspects. However, the most striking deficiency was the extremely poor documentation, reflecting a lack of awareness among clinicians regarding its importance. Local policymakers should focus on systematic application of quality improvement strategies in order to achieve greater patient safety and further reductions in the maternal mortality rate

Domestic violence victims in a hospital setting:prevalence, health impact and patients' preferences - results from a cross-sectional study

Background: Domestic violence (DV) is a widespread yet commonly underdetected problem with severe impact on physical and mental health. To date, only limited information is available on prevalence and detection-rates of victims of DV in hospital settings. Objective: The aim of this study was (a) to assess the prevalence and impact of DV on physical and mental health as well as risk-factors associated with it, (b) to determine how many patients had been asked directly about DV in the hospital and (c) to investigate patients' preferences about being asked about DV in a hospital setting. Methods: Adult inpatients and outpatients at seven somatic departments at the University Hospital Innsbruck (Austria) were included consecutively in this ad-hoc, cross-sectional paper-and-pencil questionnaire-based study. In total, n = 2,031 patients were assessed regarding their experiences with DV. They also reported on whether they had been asked about DV at the hospital and whether they would mind being asked about it. To evaluate the impact of DV on patients' self-reported physical and mental health, odds ratios were calculated using binary logistic regression. Results: DV was reported by 17.4% of patients, with 4.0% indicating current DV exposure. Lifetime DV exposure was associated with a significant risk for both physical and mental health-problems. Only 4.8% of patients with DV exposure had ever been asked about it by hospital staff. While patients with a history of DV were more open to being asked about DV than patients without DV (78.2% vs. 72.9%), overall acceptance was still high (74%). Conclusion: DV is a frequently overlooked problem with detrimental effects on physical and mental health. While high acceptance of DV assessment was found, only a small proportion of affected patients had indeed been assessed for DV. Screening for DV in hospitals may thus increase the number of identified patients

Reconstitution of Nup157 and Nup145N into the Nup84 Complex

About 30 different nucleoporins (Nups) constitute the nuclear pore complex. We have affinity-purified 28 of these nuclear pore proteins and identified new nucleoporin interactions by this analysis. We found that Nup157 and Nup170, two members of the large structural Nups, and the Gly-Leu-Phe-Gly nucleoporin Nup145N specifically co-purified with members of the Nup84 complex. In addition, Nup145N co-enriched during Nup157 purification. By in vitro reconstitution, we demonstrate that Nup157 and Nup145N form a nucleoporin subcomplex. Moreover, we show that Nup157 and Nup145N bind to the heptameric Nup84 complex. This assembly thus represents approximately one-third of all nucleoporins. To characterize Nup157 structurally, we purified and analyzed it by electron microscopy. Nup157 is a hollow sphere that resembles a clamp or a gripping hand. Thus, we could reconstitute an interaction between a large structural Nup, an FG repeat Nup, and a major structural module of the nuclear pore complex

Impact of mastectomy on the social well-being and family dynamics of breast cancer female patients in the Gaza Strip

Background: The impact of mastectomy on social well-being (SWB) and family dynamics (FD) may involve the individual, social role and perception of the usefulness of social and family support affects. The purpose of the current study is to identify that impact and its related implications on SWB and FD. Methods: This was a cross-sectional study in which a total of 173 female patients who had mastectomy in GS hospitals completed a face-to-face questionnaire designed by the researchers; which contains 3 sections including: socio-demographic data, SWB and FD. All measures utilized a five-point Likert-type scale ranging from 1 (worst outcome) to 5 (best outcome). The study was conducted at European Gaza Hospital (n= 60) and Alshifaa Hopsital (n= 113) in the GS from August 2015 to September 2016. The data was analyzed using SPSS software. Results: Among 173 female patients, the mean age was 51 years