The tomato Prf complex is a molecular trap for bacterial effectors based on Pto transphosphorylation

The bacteria Pseudomonas syringae is a pathogen of many crop species and one of the model pathogens for studying plant and bacterial arms race coevolution. In the current model, plants perceive bacteria pathogens via plasma membrane receptors, and recognition leads to the activation of general defenses. In turn, bacteria inject proteins called effectors into the plant cell to prevent the activation of immune responses. AvrPto and AvrPtoB are two such proteins that inhibit multiple plant kinases. The tomato plant has reacted to these effectors by the evolution of a cytoplasmic resistance complex. This complex is compromised of two proteins, Prf and Pto kinase, and is capable of recognizing the effector proteins. How the Pto kinase is able to avoid inhibition by the effector proteins is currently unknown. Our data shows how the tomato plant utilizes dimerization of resistance proteins to gain advantage over the faster evolving bacterial pathogen. Here we illustrate that oligomerisation of Prf brings into proximity two Pto kinases allowing them to avoid inhibition by the effectors by transphosphorylation and to activate immune responses

Biochemical Comparison of Anopheles gambiae and Human NADPH P450 Reductases Reveals Different 2′-5′-ADP and FMN Binding Traits

NADPH-cytochrome P450 oxidoreductase (CPR) plays a central role in chemical detoxification and insecticide resistance in Anopheles gambiae, the major vector for malaria. Anopheles gambiae CPR (AgCPR) was initially expressed in Eschericia coli but failed to bind 2′, 5′-ADP Sepharose. To investigate this unusual trait, we expressed and purified a truncated histidine-tagged version for side-by-side comparisons with human CPR. Close functional similarities were found with respect to the steady state kinetics of cytochrome c reduction, with rates (kcat) of 105 s−1 and 88 s−1, respectively, for mosquito and human CPR. However, the inhibitory effects of 2′,5′-ADP on activity were different; the IC50 value of AgCPR for 2′, 5′ –ADP was significantly higher (6–10 fold) than human CPR (hCPR) in both phosphate and phosphate-free buffer, indicative of a decrease in affinity for 2′, 5′- ADP. This was confirmed by isothermal titration calorimetry where binding of 2′,5′-ADP to AgCPR (Kd = 410±18 nM) was ∼10 fold weaker than human CPR (Kd = 38 nM). Characterisation of the individual AgFMN binding domain revealed much weaker binding of FMN (Kd = 83±2.0 nM) than the equivalent human domain (Kd = 23±0.9 nM). Furthermore, AgCPR was an order of magnitude more sensitive than hCPR to the reductase inhibitor diphenyliodonium chloride (IC50 = 28 µM±2 and 361±31 µM respectively). Taken together, these results reveal unusual biochemical differences between mosquito CPR and the human form in the binding of small molecules that may aid the development of ‘smart’ insecticides and synergists that selectively target mosquito CPR

Synchronous malignant B-cell lymphoma and gastric tubular adenocarcinoma associated with paraneoplastic cutaneous vasculitis: hypereosinophilic syndrome with mixed cryoglobulinemia is an important sign of paraneoplastic syndrome

Gastric adenocarcinoma developing concomitantly with a lymphoma is rare. Furthermore, B-cell lymphoma, originating from lymph nodes, with eosinophilia is extremely rare. We report here a case with a synchronous diffuse large B-cell lymphoma (DLBCL) and an early adenocarcinoma of the stomach. In addition, this case seemed to be associated with paraneoplastic cutaneous vasculitis caused by hypereosinophilic syndrome (HES) with mixed cryoglobulinemia (MC). Many neoplastic diseases that affect internal organs display cutaneous manifestations, which may be the presenting signs and symptoms of the underlying malignancy. In particular, the association between cutaneous vasculitis and malignancy has been widely reviewed, and recently neoplasms have been suggested to produce antigens and the resultant immune complex formations, activating the serum complement, thus cause paraneoplastic vasculitis. In this case, severe eosinophilia and cryoglobulinemia with low complements were observed in a laboratory test. A biopsy specimen from a skin lesion revealed leukocytoclastic vasculitis with severe perivascular infiltration of eosinophils. The cutaneous vasuculitis was considered to be a manifestation of HES with MC, although there were no etiological factors of HES and MC. Therefore, the vasculitis seems to be a symptom of paraneoplastic syndrome in this case. Our finding suggests that the potential presence of malignancies should be kept in mind as a possible underlying disorder especially in the presence of HES with MC; this possibility is interesting also as regards at least part of the pathogenesis for paraneplastic syndrome

Role of mitochondrial raft-like microdomains in the regulation of cell apoptosis

Lipid rafts are envisaged as lateral assemblies of specific lipids and proteins that dissociate and associate rapidly and form functional clusters in cell membranes. These structural platforms are not confined to the plasma membrane; indeed lipid microdomains are similarly formed at subcellular organelles, which include endoplasmic reticulum, Golgi and mitochondria, named raft-like microdomains. In addition, some components of raft-like microdomains are present within ER-mitochondria associated membranes. This review is focused on the role of mitochondrial raft-like microdomains in the regulation of cell apoptosis, since these microdomains may represent preferential sites where key reactions take place, regulating mitochondria hyperpolarization, fission-associated changes, megapore formation and release of apoptogenic factors. These structural platforms appear to modulate cytoplasmic pathways switching cell fate towards cell survival or death. Main insights on this issue derive from some pathological conditions in which alterations of microdomains structure or function can lead to severe alterations of cell activity and life span. In the light of the role played by raft-like microdomains to integrate apoptotic signals and in regulating mitochondrial dynamics, it is conceivable that these membrane structures may play a role in the mitochondrial alterations observed in some of the most common human neurodegenerative diseases, such as Amyotrophic lateral sclerosis, Huntington's chorea and prion-related diseases. These findings introduce an additional task for identifying new molecular target(s) of pharmacological agents in these pathologies

Adolescents' reactions to participating in ethically sensitive research: A prospective self-report study

Background: Conducting psychological research with adolescents is imperative for better understanding, prevention and treatment of mental illness. However there is concern that research addressing topics such as mental illness, substance use and suicidality has potential to distress participants, particularly youth. Method: We administered a questionnaire to 1973 adolescents (13-18 years) at two time points, one year apart. Participants responded to items regarding nonsuicidal self-injury, psychological distress, history of physical and/or sexual abuse, adverse life events, alcohol use, suicidal behaviour, self-efficacy, and coping skills as well as two open-ended questions regarding whether they enjoyed participating in the research and whether participation worried or upset them. Results: Most youth (74 %) enjoyed participation and cited altruistic reasons and a greater self-awareness as reasons. Those reporting being upset by the questionnaire (15 %) reported poorer psychological functioning than their peers. Youth who were upset by their participation at baseline, but who reported enjoying the questionnaire at follow-up reported improved psychosocial functioning over time, while the reverse was true for those who initially enjoyed participation but later reported the questionnaire upset them. Conclusions: Results suggest researchers acknowledge benefits for young people who participate in research, but also be mindful of the potential for distress among the most at risk youth

Symptoms of gastroesophageal reflux disease in severely mentally retarded people: a systematic review

<p>Abstract</p> <p>Background</p> <p>Gastroesophageal reflux disease (GERD) occurs when stomach acid frequently backs up (or refluxes) into the gullet (or esophagus), and it has serious consequences for the quality of life. Usually this is felt as heartburn. Because severely mentally retarded people usually do not utter complaints of heartburn, it requires a high index of suspicion to discover possible GERD. Therefore it is relevant for care professionals such as nurses to have knowledge of those with a higher risk of GERD and of the possible manifestations of GERD.</p> <p>Methods</p> <p>Using a predefined search method, electronic databases were searched for studies relating the presence of symptoms to the presence of GERD. Relevant data were extracted and the methodological quality of the studies assessed. The results of the included studies were synthesized and conclusions about the level of evidence were drawn.</p> <p>Results</p> <p>Nineteen studies were found relating symptoms to the presence of GERD. Only four were of good methodological quality. The studies were very diverse concerning the studied population, the study method, and the kind of symptoms examined. This makes it difficult to synthesize the results of the studies. There is evidence that patients with cerebral palsy, patients using anticonvulsive drugs, and those with an IQ lower than 35 more frequently have GERD. There is also evidence that vomiting, rumination and hematemesis are associated with a higher risk of the presence of GERD, whereas there is no clear scientific evidence that particular behavior symptoms are indicative for GERD.</p> <p>Conclusion</p> <p>The possible manifestations of GERD are many and varied. A guideline will be made for care professionals to aid systematic observation of possible manifestations of GERD.</p

Impact of Macrophage Inflammatory Protein-1α Deficiency on Atherosclerotic Lesion Formation, Hepatic Steatosis, and Adipose Tissue Expansion

Macrophage inflammatory protein-1α (CCL3) plays a well-known role in infectious and viral diseases; however, its contribution to atherosclerotic lesion formation and lipid metabolism has not been determined. Low density lipoprotein receptor deficient (LDLR−/−) mice were transplanted with bone marrow from CCL3−/− or C57BL/6 wild type donors. After 6 and 12 weeks on western diet (WD), recipients of CCL3−/− marrow demonstrated lower plasma cholesterol and triglyceride concentrations compared to recipients of C57BL/6 marrow. Atherosclerotic lesion area was significantly lower in female CCL3−/− recipients after 6 weeks and in male CCL3−/− recipients after 12 weeks of WD feeding (P<0.05). Surprisingly, male CCL3−/− recipients had a 50% decrease in adipose tissue mass after WD-feeding, and plasma insulin, and leptin levels were also significantly lower. These results were specific to CCL3, as LDLR−/− recipients of monocyte chemoattractant protein−/− (CCL2) marrow were not protected from the metabolic consequences of high fat feeding. Despite these improvements in LDLR−/− recipients of CCL3−/− marrow in the bone marrow transplantation (BMT) model, double knockout mice, globally deficient in both proteins, did not have decreased body weight, plasma lipids, or atherosclerosis compared with LDLR−/− controls. Finally, there were no differences in myeloid progenitors or leukocyte populations, indicating that changes in body weight and plasma lipids in CCL3−/− recipients was not due to differences in hematopoiesis. Taken together, these data implicate a role for CCL3 in lipid metabolism in hyperlipidemic mice following hematopoietic reconstitution

Transforming healthcare through regenerative medicine

Regenerative medicine therapies, underpinned by the core principles of rejuvenation, regeneration and replacement, are shifting the paradigm in healthcare from symptomatic treatment in the 20th century to curative treatment in the 21st century. By addressing the reasons behind the rapid expansion of regenerative medicine research and presenting an overview of current clinical trials, we explore the potential of regenerative medicine to reshape modern healthcare

Methylation QTLs in the developing brain and their enrichment in schizophrenia risk loci

We characterized DNA methylation quantitative trait loci (mQTLs) in a large collection (n = 166) of human fetal brain samples spanning 56-166 d post-conception, identifying >16,000 fetal brain mQTLs. Fetal brain mQTLs were primarily cis-acting, enriched in regulatory chromatin domains and transcription factor binding sites, and showed substantial overlap with genetic variants that were also associated with gene expression in the brain. Using tissue from three distinct regions of the adult brain (prefrontal cortex, striatum and cerebellum), we found that most fetal brain mQTLs were developmentally stable, although a subset was characterized by fetal-specific effects. Fetal brain mQTLs were enriched amongst risk loci identified in a recent large-scale genome-wide association study (GWAS) of schizophrenia, a severe psychiatric disorder with a hypothesized neurodevelopmental component. Finally, we found that mQTLs can be used to refine GWAS loci through the identification of discrete sites of variable fetal brain methylation associated with schizophrenia risk variants

The Prevalence and Drug Sensitivity of Tuberculosis among Patients Dying in Hospital in KwaZulu-Natal, South Africa: A Postmortem Study

A postmortem study by Ted Cohen and colleagues reveals a huge toll of tuberculosis among patients dying in hospitals in KwaZulu-Natal, South Africa