How autistic women are aware of their body and take care of their health? Focus on menstruation cycles and gynecological care

Objective

The combination of femininity and inequality is an increasingly studied in the field of social medicine, even more if the girls or women in question experience conditions of disability or neurodivergence. The onset of menstruation, menarche, constitutes a significant and transformative event in women's lives comprising a true and proper watershed in mental and reproductive health and sexual welfare. The onset of menstruation has a profound effect not just for girls but, in the case of disabled girls, for the whole family. In this scoping review, we have researched the literature in studies which consider the issue of menstruation and autism. The works in scientific literature have been selected which, in the last 5 years, investigated the issue of menstrua-tion for autistic girls and/or women.

Results

Selected studies, although few in number, have all equally evidenced the total lack of in-depth understanding of this theme, notwithstanding the fact that females, girls and women with autism would benefit from specialized services if these existed. Families, girls and women involved, moreover, although not experiencing menstruation per se in a negative light, note a deterioration in their condition particularly in respect of sensorial perception and the intensification of anxious depressive instances. This work highlights the need to deepen the aspects concerning the period in autistic girls/women, up to now the question appears to have been little studied, investigated in an uneven way. We propose a social medical program to improve sexual-affective knowledge and body awareness in autistic people.

Social Skills and Cognitive Training to Support Work-Related Skills and Job Placement in a Group of Autistic Adults : Effectiveness of a Neuropsychological and Social Skills Intervention: A Case Series Study on a Pilot Program

Autistic people may have difficulties in finding and keeping a job. Studies highlight that only 34% of autistic people are employed compared to 54% of people with disability. 58% of people with ASD have never had a job. Social cognition and cognitive strains may also have a significant impact on working life. The primary goal of our project is supporting autistic people through a training program focused on neuropsychological and social skills training to improve participant' job skills. Through an Individual Placement and Support model the project involved various Partners to guide, identify skills and interests, provide cognitive and psychological support for autistic people. Results highlighted neuropsychological training efficacy, especially in inhibitory control and good rate of employment status at the end of the project. Findings are encouraging and underline the importance of a multidisciplinary approach to support autistic people in their work life considering their expectations, needs and inclinations.

Predictive value of computed tomography on surgical resectability in locally advanced pancreatic cancer treated with multiagent induction chemotherapy: Results from a prospective, multicentre phase 2 trial (NEOLAP-AIO-PAK-0113)

PURPOSE

To assess the role of current imaging-based resectability criteria and the degree of radiological downsizing in locally advanced pancreatic adenocarcinoma (LAPC) after multiagent induction chemotherapy (ICT) in multicentre, open-label, randomized phase 2 trial.

METHOD

LAPC patients were prospectively treated with multiagent ICT followed by surgical exploration within the NEOLAP trial. All patients underwent CT scan at baseline and after ICT to assess resectability status according to national comprehensive cancer network guidelines (NCCN) criteria and response evaluation criteria in solid tumors (RECIST) at the local study center and retrospectively in a central review. Imaging results were compared in terms of local and central staging, downsizing and pathological resection status.

RESULTS

83 patients were evaluable for central review of baseline and restaging imaging results. Downstaging by central review was rarely seen after multiagent ICT (7.7%), whereas tumor downsizing was documented frequently (any downsizing 90.4%, downsizing to partial response (PR) according to RECIST: 26.5%). Patients with any downsizing showed no significant different R0 resection rate (37.3%) as patients that fulfilled the criteria of PR (40.9%). The sensitivity of any downsizing for predicting R0 resection was 97% with a negative predictive value (NPV) of 0.88. ROC-analysis revealed that tumor downsizing was a predictor of R0 resection (AUC 0.647, p = 0.028) with a best cut-off value of 22.5% downsizing yielding a sensitivity of 65% and a specificity of 61%.

CONCLUSIONS

Imaging-based tumor downsizing and not downstaging can guide the selection of patients with a realistic chance of R0-resection in LAPC after multi-agent ICT.

Prognostic and predictive value of CA 19-9 in locally advanced pancreatic cancer treated with multiagent induction chemotherapy: results from a prospective, multicenter phase II trial (NEOLAP-AIO-PAK-0113)

BACKGROUND

The prognostic and predictive value of carbohydrate antigen 19-9 (CA 19-9) in locally advanced pancreatic cancer (LAPC) has not yet been defined from prospective randomized controlled trials (RCTs).

PATIENTS AND METHODS

A total of 165 LAPC patients were treated within the NEOLAP RCT for 16 weeks with multiagent induction chemotherapy [ICT; either nab-paclitaxel/gemcitabine alone or nab-paclitaxel/gemcitabine followed by FOLFIRINOX (combination of fluorouracil, leucovorin, irinotecan, and oxaliplatin)] followed by surgical exploration of all patients without evidence of disease progression. CA 19-9 was determined at baseline and after ICT and correlated with overall survival (OS) and secondary R0 resection rate.

RESULTS

From the NEOLAP study population (N = 165) 133 patients (81%) were evaluable for CA 19-9 at baseline and 81/88 patients (92%) for post-ICT CA 19-9 response. Median OS (mOS) in the CA 19-9 cohort (n = 133) was 16.2 months [95% confidence interval (CI) 13.0-19.4] and R0 resection (n = 31; 23%) was associated with a significant survival benefit [40.8 months (95% CI 21.7-59.8)], while R1 resected patients (n = 14; 11%) had no survival benefit [14.0 (95% CI 11.7-16.3) months, hazard ratio (HR) 0.27; P = 0.001]. After ICT most patients showed a CA 19-9 response (median change from baseline: -82%; relative decrease ≥55%: 83%; absolute decrease to ≤50 U/ml: 43%). Robust CA 19-9 response (decrease to ≤50U/ml) was significantly associated with mOS [27.8 (95% CI 18.4-37.2) versus 16.5 (95% CI 11.7-21.2) months, HR 0.49; P = 0.013], whereas CA 19-9 baseline levels were not prognostic for OS. Multivariate analysis demonstrated that a robust CA 19-9 response was an independent predictive factor for R0 resection. Using a CA 19-9 decrease to ≤61 U/ml as optimal cut-off (by receiver operating characteristic analysis) yielded 72% sensitivity and 62% specificity for successful R0 resection, whereas CA 19-9 nonresponders (<20% decrease or increase) had no chance for successful R0 resection.

CONCLUSIONS

CA 19-9 response after multiagent ICT provides relevant prognostic and predictive information and is useful in selecting LAPC patients for explorative surgery.

CLINICAL TRIAL NUMBER

ClinicalTrials.govNCT02125136; https://clinicaltrials.gov/ct2/show/NCT02125136; EudraCT 2013-004796-12; https://www.clinicaltrialsregister.eu/ctr-search/trial/2013-004796-12/results.

Exploring the selective gray matter profile of autism spectrum disorder through Bayes Factor Modeling

Introduction

Despite decades of brain MRI research demonstrating atypical neuroanatomical substrate in patients with autism spectrum disorder (ASD), it remains unclear whether and to what extent disorder-selective neuroanatomical abnormalities occur in this spectrum. This, and the fact that multiple brain disorders report a common neuroanatomical substrate, makes transference and the application of neuroimaging findings into the clinical setting an open challenge.

Objectives

To investigate the selective neuroanatomical alteration profile of the ASD brain, we employed a meta-analytic, data-driven, and reverse inference-based approach (i.e.; Bayes fACtor mOdeliNg).

Methods

Eligible voxel-based morphometry data were extracted by a standardized search on BrainMap and MEDLINE databases (849 published experiments, 131 brain disorders, 22747 clinical subjects, 16572 x-y-z coordinates). Two distinct datasets were generated: the ASD dataset, composed of ASD-related data; and the non-ASD dataset, composed of all other clinical conditions data. Starting from the two unthresholded activation likelihood estimation (ALE) maps, the calculus of the Bayes fACtor mOdeliNg was performed. This allowed us to obtain posterior probability distributions on the evidence of brain alteration specificity in ASD.

Results

We revealed both cortical and cerebellar areas of neuroanatomical alteration selectivity in ASD. Eight clusters showed a selectivity value ≥ 90%, namely the bilateral precuneus, the right inferior occipital gyrus, left lobule IX, left Crus II, right Crus I, and the right lobule VIIIA (Fig. 1).

Conclusions

The identification of this neuroanatomical pattern provides new insights into the complex pathophysiology of ASD, opening attractive prospects for future neuroimaging-based interventions.

Disclosure

No significant relationships.

[Rescue of injured horses, cattle and pigs from manure and cesspools by the large animal rescue service Switzerland and Liechtenstein (GTRD CH/FL)®]

INTRODUCTION

One of the varied tasks of the Large Animal Rescue Service Switzerland and Liechtenstein (GTRD CH/FL)® is the recovery of animals from manure and cesspools. The aim of the present retrospective study was the evaluation of the rescue protocols of the GTRD CH/FL from such operations and the documentation of a rescue procedure. In the past 25 years, a total of 176 animals have been rescued from manure and cesspools. These included 113 cattle, 51 horses and 12 pigs. All animals could be safely rescued with the animal rescue and transport net (TBTN) or the large animal vertical rescue set (GTVBS). The TBTN is used when the opening of the cesspool is large enough to recover the animal in a horizontal position. The GTVBS is particularly suitable for narrow openings, as the recovery in a -vertical position does not require any constructional modification or the enlargement of the cesspool opening. Both rescue harnesses are characterized by reliable handling and allow gentle recovery.

Probation of the offender with high functioning autistic traits and comorbidity. A case study

Introduction

When the Criminal Court Judge applies probation, the offender is entrusted to social assistants for the necessary observation, treatment and support. This case study examines the probation of a young man with high-functioning autistic traits, personality disorder and legal/illegal substance abuse. This young man, who arrived only in adulthood to a diagnosis of autistic traits, is aware only that is non-neurotypical. He does not recognize that he needs treatment for personality disorder, alcohol, substance and drug abuse. He faces a sentence of more than three years in prison but the Judge suspends the criminal trial.

Objectives

Clarify the relationship between high functioning autistic traits, comorbidity with personality disorder and drugs/substance abuse, and crimes committed; also describe the orientation of the Judge and what difficulties arise during the probation.

Methods

Examination of the criminal file and medical documents of the offender, known by social and health services.

Results

The offender correlates the crimes and its frailty with autism and not with antisocial behaviours to gain economic benefits from drug dealing.

Conclusions

The deficit in the social communication and lack of empathy for child victimes, for example, limits the effectiveness of probation. The probation, for a young with high-functioning autistic traits and comorbidity, does not seem to give satisfactory results in terms of rehabilitation and social integration, nor does it produce the extinction of crime.

Comparison of conservative versus surgical therapy for acute appendicitis with abscess in five German hospitals

INTRODUCTION

The aim of this study was to evaluate the effectiveness of initially conservative therapy compared to immediate appendectomy for acute appendicitis with abscess in terms of medical and economic outcomes.

METHODS

Of all the patients treated for appendicitis from January 2009 to December 2017 in five German hospitals, 240 were included in the study. Fifty-three patients received conservative (CON) and 195 patients received surgical (SUR) therapy as initial treatment.

RESULTS

Length of stay was similar (12.5 days in CON vs. 13.3 days in SUR, p = 0.530). Readmission rate was higher in the conservative group (54.7% vs. 6.2%, p < 0.001). The majority (53.7%) of the 41 operations in CON group were appendectomies (22 procedures), 1 (4.5%) of them was in the first hospital stay because of persisting symptoms, 21 (95.5%) after a recovery interval. Seven (33.3%) of the recovery appendectomies were performed due to persisting or recurrent symptoms and 14 (66.7%) due to the request of patient. Twenty-one patients (39.6%) in the CON group did not need surgery. The rates of complication-related operations per patient (0.04 versus 0.58, p < 0.001), conversions of surgical technique (1.9% vs. 34.9%, p = 0.0287), and extended resections (1.9% vs. 31.3%, p < 0.001) were higher in SUR group. Furthermore, morbidity, hospital costs, and loss in quality of life were significantly higher in the surgical group (17.0% vs. 66.2%, p < 0.001; € 5044 vs. € 8457, p < 0.001, and 4.3 days vs. 7.5 days, p < 0.001, CON vs. SUR).

CONCLUSION

Initially, conservative treatment for acute appendicitis with abscess is preferable to immediate surgical treatment in reduction of morbidity, hospital costs, and loss in quality of life.

Mindreading abilities and borderline personality disorder: A comprehensive assessment using the Theory of Mind Assessment Scale

Numerous studies have examined mindreading in borderline personality disorder (BPD). However, the empirical data obtained to date have not facilitated the development of a clear clinical profile of mindreading impairment in BPD due to a lack of consistency or incongruence across studies. One possible explanation for these inconsistencies and divergences in the current literature may lie in the multidimensional character of the mindreading construct; moreover, the heterogeneity of the experimental measures used to assess individuals with BPD mindreading skills may also need to be taken into account. The aim of the present study is to investigate mindreading skills and impairments in patients with BPD through direct comparison of a wide range of mindreading dimensions using a comprehensive semistructured interview, the Theory of Mind Assessment Scale (Th.o.m.a.s.) (Bosco et al., 2009). Our results show that the performance of patients with BPD differs from that of healthy controls only in certain specific dimensions of mindreading. The difficulties encountered by the patients with BPD typically emerge when mindreading tasks require them to disentangle their own subjective mindreading from that of another person, in other words, when they were required to assume an allocentric perspective.

Newborn screening for homocystinurias: Recent recommendations versus current practice

PURPOSE

To assess how the current practice of newborn screening (NBS) for homocystinurias compares with published recommendations.

METHODS

Twenty-two of 32 NBS programmes from 18 countries screened for at least one form of homocystinuria. Centres provided pseudonymised NBS data from patients with cystathionine beta-synthase deficiency (CBSD, n = 19), methionine adenosyltransferase I/III deficiency (MATI/IIID, n = 28), combined remethylation disorder (cRMD, n = 56) and isolated remethylation disorder (iRMD), including methylenetetrahydrofolate reductase deficiency (MTHFRD) (n = 8). Markers and decision limits were converted to multiples of the median (MoM) to allow comparison between centres.

RESULTS

NBS programmes, algorithms and decision limits varied considerably. Only nine centres used the recommended second-tier marker total homocysteine (tHcy). The median decision limits of all centres were ≥ 2.35 for high and ≤ 0.44 MoM for low methionine, ≥ 1.95 for high and ≤ 0.47 MoM for low methionine/phenylalanine, ≥ 2.54 for high propionylcarnitine and ≥ 2.78 MoM for propionylcarnitine/acetylcarnitine. These decision limits alone had a 100%, 100%, 86% and 84% sensitivity for the detection of CBSD, MATI/IIID, iRMD and cRMD, respectively, but failed to detect six individuals with cRMD. To enhance sensitivity and decrease second-tier testing costs, we further adapted these decision limits using the data of 15 000 healthy newborns.

CONCLUSIONS

Due to the favorable outcome of early treated patients, NBS for homocystinurias is recommended. To improve NBS, decision limits should be revised considering the population median. Relevant markers should be combined; use of the postanalytical tools offered by the CLIR project (Collaborative Laboratory Integrated Reports, which considers, for example, birth weight and gestational age) is recommended. tHcy and methylmalonic acid should be implemented as second-tier markers.

The GlpF residue Trp219 is part of an amino-acid cluster crucial for aquaglyceroporin oligomerization and function

The vestibule loop regions of aquaglyceroporins are involved in accumulation of glycerol inside the channel pore. Even though most loop regions do not show high sequence similarity among aquaglyceroporins, loop E is highly conserved in aquaglyceroporins, but not in members of the homologous aquaporins. Specifically, a tryptophan residue is extremely conserved within this loop. We have investigated the role of this residue (Trp219) that deeply protrudes into the protein and potentially interacts with adjacent loops, using the E. coli aqualgyeroporin GlpF as a model. Replacement of Trp219 affects the activity of GlpF and impairs the stability of the tetrameric protein. Furthermore, we have identified an amino acid cluster involving Trp219 that stabilizes the GlpF tetramer. Based on our results we propose that Trp219 is key for formation of a defined vestibule structure, which is crucial for glycerol accumulation as well as for the stability of the active GlpF tetramer.

Copy number variants analysis in a cohort of isolated and syndromic developmental delay/intellectual disability reveals novel genomic disorders, position effects and candidate disease genes

BACKGROUND

Array-comparative genomic hybridization (array-CGH) is a widely used technique to detect copy number variants (CNVs) associated with developmental delay/intellectual disability (DD/ID).

AIMS

Identification of genomic disorders in DD/ID.

MATERIALS AND METHODS

We performed a comprehensive array-CGH investigation of 1,015 consecutive cases with DD/ID and combined literature mining, genetic evidence, evolutionary constraint scores, and functional information in order to assess the pathogenicity of the CNVs.

RESULTS

We identified non-benign CNVs in 29% of patients. Amongst the pathogenic variants (11%), detected with a yield consistent with the literature, we found rare genomic disorders and CNVs spanning known disease genes. We further identified and discussed 51 cases with likely pathogenic CNVs spanning novel candidate genes, including genes encoding synaptic components and/or proteins involved in corticogenesis. Additionally, we identified two deletions spanning potential Topological Associated Domain (TAD) boundaries probably affecting the regulatory landscape.

DISCUSSION AND CONCLUSION

We show how phenotypic and genetic analyses of array-CGH data allow unraveling complex cases, identifying rare disease genes, and revealing unexpected position effects.

Intellectual developmental disorders, autism, and schizophrenia spectrum: New boundaries in the neurodevelopmental perspective

Background and aim

Recent evidences of clinical overlap, familial co-aggregation, and shared genetic alterations support a neurodevelopmental deviation to represent a probable common vulnerability factor not only for the psychiatric disorders included in the meta-structure of neurodevelopmental disorders, but also for other major psychiatric disorders, including schizophrenia.

The present paper reviews the literature to identify (1) positive and negative implications of the increasing enlargement of the group of neurodevelopmental disorders and (2) most useful clinical aspect for re-defining diagnostic boundaries between syndromic groups.

Methods

The search purpose was reached through a systematic mapping of literature.

Results

The last years’ trend to increasingly enlarge the number of psychiatric features comprised in the autism spectrum should be better evaluated for potential negative impact on research and clinical resources for those autistic syndromes more reliable with Kanner's descriptions or associated with lower personal functioning profiles and different level of ID.

Crucial clinical aspects for the differentiation resulted to be age of onset, interest towards others, main positive symptoms, and anatomical anomalies of the central nervous system.

Conclusions

While on one hand the neurodevelopmental perspective might contribute to a better understanding of the multifactorial aetiopathogenetic mechanisms underlying many psychiatric disorders and provide new intervention strategies, on the other hand it might determine a premature abandonment of the traditional nosology and the appearance of very broad spectrum conditions covering all the range of current psychopathology.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Toxoplasmosis, Parvovirus, and Cytomegalovirus in Pregnancy

There are several infections in adults that warrant special consideration in pregnant women given the potential fetal consequences. Among these are toxoplasmosis, parvovirus B19, and cytomegalovirus. These infections have an important impact on the developing fetus, depending on the timing of infection. This article reviews the modes of transmission as well as maternal and neonatal effects of each of these infections. In addition, the article outlines recommended testing, fetal surveillance, and treatment where indicated.

Seronegative Maternal Ocular Myasthenia Gravis and Delayed Transient Neonatal Myasthenia Gravis

Background Myasthenia gravis (MG) is an autoimmune disorder with fluctuating muscle weakness, divided into generalized and localized (ocular) forms. Maternal antibodies to acetylcholine receptors cross the placenta and may cause transient neonatal myasthenia gravis (TNMG). We present a case of seronegative maternal ocular MG and delayed TNMG. Case A 29-year-old G3P1011 underwent cesarean birth of a male infant who developed oxygen desaturation requiring supplemental oxygen on day of life (DOL) 3. Based on the clinical course and after exclusion of other diagnoses, the infant was diagnosed with TNMG. Infant's condition improved spontaneously and he was weaned off supplemental oxygen and discharged home on DOL 12. Conclusion Infants born to mothers with seronegative localized (ocular) MG are also susceptible to TNMG which may be late in onset.

Referral rates in Swiss primary care with a special emphasis on reasons for encounter

QUESTIONS UNDER STUDY

Referrals from primary to secondary care reflect a crucial role of primary care physicians (PCPs). Most referral rates are based on the number of consultations, rather than on the number of problems addressed during consultations (reasons for encounter = RFE). The aim of the study was to update data on consultations, RFE and referrals in Swiss primary care and calculate a referral rate based on RFE rather than on the number of consultations.

METHOD

Cross-sectional study in Swiss primary care. PCPs collected data on consultations on 15 different days in three nonconsecutive months in 2012/2013. Demographic data of patients and up to six RFE per consultation were collected. For each RFE the PCP had to indicate whether a referral was initiated. Data were analysed using descriptive statistics.

RESULTS

Ninety PCPs (18.9% females) participated and 24 774 consultations with 42 890 RFE (corresponding to 1.73 [standard deviation 1.07] RFE per consultation) were recorded. A total of 2 427 RFE (of 2 341 consultations) led to a referral, corresponding to a referral rate of 9.44% (95% confidence interval [CI] 9.08-9.81%) based on consultations and 5.65% (95% CI 5.43-5.87%) based on the number of RFE.

CONCLUSIONS

An average of 1.7 RFE per consultation and a broad clinical spectrum of problems were presented in primary care; nevertheless, 94.3% of all problems were solved in primary care, reflecting the crucial role of PCPs as a coordinator of healthcare.

When two turn into one: evolution of membrane transporters from half modules

The recently increasing number of atomic structures for active transporters has not only revealed strong conservation in the architecture of sequence-unrelated transporter families, but also identified a unifying element called the 'inverted repeat topology,' which is found in nearly all transporter folds to date. Indeed, most membrane transporters consist of two or more domains with similar structure, so-called repeats. It is tempting to speculate that transporters have evolved by duplication of one repeat followed by gene fusion and modification events. An intriguing question is, whether recent genes encoding such a 'half-transporter' still exist as independent folding units. Although it seems likely that the evolution of membrane transport proteins, which harbor internal repeats, is linked to these minimal structural building blocks, their identification in the absence of structural data represents a major challenge, as sequence homology is not an issue. In this review we discuss two protein families, the DedA family and the SWEET family, being potential half-transporters and putative ancestors for two of the most abundant secondary transporter families, the MFS family and the LeuT-fold family.

The Escherichia coli Envelope Stress Sensor CpxA Responds to Changes in Lipid Bilayer Properties

The Cpx stress response system is induced by various environmental and cellular stimuli. It is also activated in Escherichia coli strains lacking the major phospholipid, phosphatidylethanolamine (PE). However, it is not known whether CpxA directly senses changes in the lipid bilayer or the presence of misfolded proteins due to the lack of PE in their membranes. To address this question, we used an in vitro reconstitution system and vesicles with different lipid compositions to track modulations in the activity of CpxA in different lipid bilayers. Moreover, the Cpx response was validated in vivo by monitoring expression of a PcpxP-gfp reporter in lipid-engineered strains of E. coli. Our combined data indicate that CpxA responds specifically to different lipid compositions.

Unawareness of bipolar disorder: the role of the cingulate cortex

Reduced awareness of illness is a well-known phenomenon that has been understudied in remitted patients with bipolar disorder. In particular, the relationship between reduced awareness and executive dysfunction is an intriguing question that has yet to be resolved. The aim of the current study is to analyze the link between reduced awareness, brain dysfunction, and concomitant cognitive-behavioral disturbances from a neurocognitive perspective. In previous studies, we demonstrated the role of the anterior cingulate cortex (ACC) in the unawareness of distinct pathologies that exhibit overlapping symptoms in the context of overlapping circuit-specific dysfunction. Given the clinical importance of the results obtained, the present study considers six aware and four unaware remitted bipolar disorder patients. Cingulate functionality was assessed with functional magnetic resonance imaging while patients performed a go/no-go task. Patients were also studied on an overall cognitive task battery and with behavioral assessment of mood changes in terms of apathy and disinhibited behavior. Unaware patients showed frontoparietal hypo-perfusion, with a significant reduction of task-sensitive activity in the bilateral superior and middle frontal gyrus, putamen, insular, and ACCs.

Die Kristallstruktur des α-Na2S5 / The Crystal Structure of α-Na2S5

Na2S5 has been Synthesized from β-Na2S2 and excess sulfur by a two step reaction. A solid state reaction at 200 °C was carried out, which was then followed by a melting reaction at 500 °C. X-ray investigations on single crystals revealed the structure of the α-modification. The orthorhombic unit cell contains four formula units; the space group is Pnma. The sulfur atoms form unbranched zig-zag-chains S5 2- in cis-conformation

Homologs of the yeast Tvp38 vesicle-associated protein are conserved in chloroplasts and cyanobacteria

Vesicle transfer processes in eukaryotes depend on specific proteins, which mediate the selective packing of cargo molecules for subsequent release out of the cells after vesicle fusion to the plasma membrane. The protein Tvp38 is conserved in yeasts and higher eukaryotes and potentially involved in vesicle transfer processes at the Golgi membrane. Members of the so-called "SNARE-associated proteins of the Tvp38-family" have also been identified in prokaryotes and those belong to the DedA protein family. Tvp38/DedA proteins are also conserved in cyanobacteria and chloroplasts. While only a single member of this family appears to be present in chloroplasts, cyanobacterial genomes typically encode multiple homologous proteins. Mainly based on our understanding of the DedA-homologous proteins of Escherichia coli, it appears likely that the function of these proteins in chloroplast and cyanobacteria involves stabilizing and organizing the structure of internal membrane systems.

Properties of amphiphilic oligonucleotide films at the air/water interface and after film transfer

The self-assembly of amphiphilic hybrid materials containing an oligonucleotide sequence at the air/water interface was investigated by means of pressure-molecular area (Π-A) isotherms. In addition, films were transferred onto solid substrates and imaged using scanning force microscopy. We used oligonucleotide molecules with lipid tails, which consisted of a single stranded oligonucleotide 11 mer containing two hydrophobically modified 5-(dodec-1-ynyl)uracil nucleobases (dU11) at the 5'-end of the oligonucleotide sequence. The air/water interface was used as confinement for the self-assembling process of dU11. Scanning force microscopy of films transferred via Langmuir-Blodgett technique revealed mono-, bi- (Π ≥ 2 mN/m) and multilayer formation (Π ≥ 30 mN/m). The first layer was 1.6 ± 0.1 nm thick. It was oriented with the hydrophilic oligonucleotide moiety facing the hydrophilic substrate while the hydrophobic alkyl chains faced air. In the second layer the oligonucleotide moiety was found to face the air. The second layer was found to cover up to 95% of the sample area. Our measurements indicated that the rearrangement of the molecules into bi- and multiple bilayers happened already at the air/water interface. Similar results were obtained with a second type of oligonucleotide amphiphile, an oligonucleotide block copolymer, which was composed of an oligonucleotide 11 mer covalently attached at the terminus to polypropyleneoxide (PPO).

Co-operation between different targeting pathways during integration of a membrane protein

The Sec and Tat pathways are both required to insert the three hydrophobic domains of the Rieske protein into the membrane.

Membrane protein assembly is a fundamental process in all cells. The membrane-bound Rieske iron-sulfur protein is an essential component of the cytochrome bc₁ and cytochrome b₆f complexes, and it is exported across the energy-coupling membranes of bacteria and plants in a folded conformation by the twin arginine protein transport pathway (Tat) transport pathway. Although the Rieske protein in most organisms is a monotopic membrane protein, in actinobacteria, it is a polytopic protein with three transmembrane domains. In this work, we show that the Rieske protein of Streptomyces coelicolor requires both the Sec and the Tat pathways for its assembly. Genetic and biochemical approaches revealed that the initial two transmembrane domains were integrated into the membrane in a Sec-dependent manner, whereas integration of the third transmembrane domain, and thus the correct orientation of the iron-sulfur domain, required the activity of the Tat translocase. This work reveals an unprecedented co-operation between the mechanistically distinct Sec and Tat systems in the assembly of a single integral membrane protein.

Molecular dissection of TatC defines critical regions essential for protein transport and a TatB-TatC contact site

The twin arginine transport (Tat) system transports folded proteins across the prokaryotic cytoplasmic membrane and the plant thylakoid membrane. TatC is the largest and most conserved component of the Tat machinery. It forms a multisubunit complex with TatB and binds the signal peptides of Tat substrates. Here we have taken a random mutagenesis approach to identify substitutions in Escherichia coli TatC that inactivate protein transport. We identify 32 individual amino acid substitutions that abolish or severely compromise TatC activity. The majority of the inactivating substitutions fall within the first two periplasmic loops of TatC. These regions are predicted to have conserved secondary structure and results of extensive amino acid insertion and deletion mutagenesis are consistent with these conserved elements being essential for TatC function. Three inactivating substitutions were identified in the fifth transmembrane helix of TatC. The inactive M205R variant could be suppressed by mutations affecting amino acids in the transmembrane helix of TatB. A physical interaction between TatC helix 5 and the TatB transmembrane helix was confirmed by the formation of a site-specific disulphide bond between TatC M205C and TatB L9C variants. This is the first molecular contact site mapped to single amino acid level between these two proteins.

Signal integration by the Cpx-envelope stress system

The Cpx-envelope stress system coordinates the expression and assembly of surface structures important for the virulence of Gram-negative pathogenic bacteria. It is comprised of the membrane-anchored sensor kinase CpxA, the cytosolic response regulator CpxR and the accessory protein CpxP. Characteristic of the group of two-component systems, the Cpx system responds to a broad range of stimuli including pH, salt, metals, lipids and misfolded proteins that cause perturbation in the envelope. Moreover, the Cpx system has been linked to inter-kingdom signalling and bacterial cell death. However, although signal specificity has been assumed, for most signals the mechanism of signal integration is not understood. Recent structural and functional studies provide the first insights into how CpxP inhibits CpxA and serves as sensor for misfolded pilus subunits, pH and salt. Here, we summarize and reflect on the current knowledge on signal integration by the Cpx-envelope stress system.

Structural basis for two-component system inhibition and pilus sensing by the auxiliary CpxP protein

Bacteria are equipped with two-component systems to cope with environmental changes, and auxiliary proteins provide response to additional stimuli. The Cpx two-component system is the global modulator of cell envelope stress in gram-negative bacteria that integrates very different signals and consists of the kinase CpxA, the regulator CpxR, and the dual function auxiliary protein CpxP. CpxP both inhibits activation of CpxA and is indispensable for the quality control system of P pili that are crucial for uropathogenic Escherichia coli during kidney colonization. How these two essential biological functions of CpxP are linked is not known. Here, we report the crystal structure of CpxP at 1.45 Å resolution with two monomers being interdigitated like "left hands" forming a cap-shaped dimer. Our combined structural and functional studies suggest that CpxP inhibits the kinase CpxA through direct interaction between its concave polar surface and the negatively charged sensor domain on CpxA. Moreover, an extended hydrophobic cleft on the convex surface suggests a potent substrate recognition site for misfolded pilus subunits. Altogether, the structural details of CpxP provide a first insight how a periplasmic two-component system inhibitor blocks its cognate kinase and is released from it.

Unusual cardioactive peptide (CCAP) from pericardial organs of the shore crab Carcinus maenas

An unusual crustacean cardioactive peptide (CCAP) from the pericardial organs of the shore crab Carcinus maenas has been purified to homogeneity by a two-step reversed-phase HPLC procedure. Manual microsequencing using the 4-(N,N-dimethylamino)azobenzene 4'-isothiocyanate/phenylisothiocyanate double-coupling technique and automated gas-phase sequencing of the oxidized peptide revealed that CCAP is a nonapeptide (M(r) 957) of the sequence Pro-Phe-[unk]Cys-Asn-Ala-Phe-Thr-Gly-Cys-NH(2). We have confirmed the sequence by chemical synthesis of the C-terminally amidated and nonamidated forms of the peptide. The presence of the amide group was indicated by lack of susceptibility to carboxypeptidase A and Y treatment and was confirmed by the observation that the native CCAP comigrated with the amidated synthetic peptide on HPLC. Native and synthetic CCAP displayed high accelerating activity on a semi-isolated crab heart preparation, whereas the nonamidated synthetic peptide was of much lower potency. The effect of CCAP was both inoand chronotropic. The two pericardial organs of one animal yielded 30-40 pmol of extractable CCAP. Its sequence does not resemble that of any known neuropeptide. However, a "mirror-image" similarity to vasopressin is conspicuous.