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Around half of the patients with Guillain-Barré syndrome (GBS) present autonomic dysfunction requiring admission to intensive care unit in up to a quarter of patients. Treatment of GBS consists of plasma exchange (PE) and intravenous immunoglobulins (IVIG). Posterior reversible encephalopathy syndrome (PRES) consists in a reversible subcortical vasogenic brain edema caused by endothelial damage triggered by abrupt blood pressure changes. We report on a woman who presented with PRES in the course of GBS treated first with IVIG, and then with PE. The present report underlines the challenge that the clinicians face when these two rare syndromes concur. The literature is not helpful considering that both blood pressure fluctuations and IVIG are reported to be involved in the pathogenesis of PRES. In the present letter, both pathogenic mechanisms and clinical management considerations are discussed.

Intravenous thrombolysis (IVT) is the treatment of choice for most patients with acute ischemic stroke. According to the recently updated guidelines, IVT should be administered in absence of absolute exclusion criteria. We aimed to assess the proportion of ischemic strokes potentially eligible and actually treated with IVT, and to explore the reasons for not administering IVT. We prospectively collected and analyzed data from 1184 consecutive ischemic stroke patients admitted to the 22 Stroke Units (SUs) of the Veneto region from September 18th to December 10th 2017. Patients were treated with IVT according to the current Italian guidelines. For untreated patients, the reasons for not administering IVT were reported by each center in a predefined model including absolute and/or relative exclusion criteria and other possible reasons. Out of 841 (71%) patients who presented within 4.5 h of stroke onset, 704 (59%) had no other absolute exclusion criteria and were therefore potentially eligible for IVT according to the current guidelines. However, only 323 (27%) patients were eventually treated with IVT. Among 861 (73%) untreated patients, 480 had at least one absolute exclusion criterion, 283 only relative exclusion criteria, 56 only other reasons, and 42 a combination of relative exclusion criteria and other reasons. Our study showed that only 46% (323/704) of the potentially eligible patients were actually treated with IVT in the SUs of the Veneto region. All healthcare professionals involved in the acute stroke pathway should make an effort to bridge this gap between eligibility and reality.

Objective To evaluate the effects of obesity-associated inflammation on influenza vaccine responses. Methods In young and elderly individuals, both lean and with obesity, antibody responses to influenza vaccination were measured. Results A decrease in in vivo vaccine responses, circulating switched memory, and transitional B cells and an increase in pro-inflammatory late/exhausted memory B cells were found. In vitro B cell function was measured by activation-induced cytidine deaminase and E47, markers of optimal antibody responses. Moreover, IL-6 production was increased, whereas IL-10 production was decreased in cultures of B cells from individuals with obesity. Markers of immune activation (TNF-α, TLR4, micro-RNAs) in unstimulated B cells were also found increased and were negatively correlated with B cell function. In order to reveal potential mechanisms, we stimulated B cells from lean individuals in vitro with leptin, the adipokine increased in obesity. Leptin increased phospho-STAT3, crucial for TNF-α production, and decreased phospho-AMPK, the energy sensing enzyme upstream of phospho-p38 MAPK and E47. Leptin-induced phospho-STAT3 and phospho-AMPK levels were similar to those in B cells from individuals with obesity. Conclusions These results demonstrate that leptin can be responsible for decreased B cell function in obesity.

Tick borne encephalitis virus infection usually shows a biphasic course. In the first stage of illness symptoms are similar to a flu-like syndrome, then after a defervescence period, fever may represent with neurological manifestations ranging from mild meningitis to severe encephalomyelitis. We report the clinical case of an adult man presented with an acute proximal hyposthenia, severe hyperckemia, clinical and laboratoristic evidence of acute tick borne virus infection. This virus has a favourite tropism for the anterior horn cells of the cervical spine segment. Polio-like syndrome, usually affecting the upper limbs, is the clinical phenotype of an infection of the cervical motoneurons. Usually myelitis is associated to severe encephalitis and a complete diagnosis may be difficult in comatose patients. Rarely, an isolated polio-like syndrome may be the sole neurological complication of tick-borne encephalitis.

Numerous bacterial pathogens use type III secretion systems (T3SSs) or T4SSs to inject or translocate virulence proteins into eukaryotic cells. Several different reporter systems have been developed to measure the translocation of these proteins. In this study, a peptide tag-based reporter system was developed and used to monitor the injection of T3S and T4S substrates. The glycogen synthase kinase (GSK) tag is a 13-residue phosphorylatable peptide tag derived from the human GSK-3β kinase. Translocation of a GSK-tagged protein into a eukaryotic cell results in host cell protein kinase-dependent phosphorylation of the tag, which can be detected with phosphospecific GSK-3β antibodies. A series of expression plasmids encoding Yop-GSK fusion proteins were constructed to evaluate the ability of the GSK tag to measure the injection of Yops by the Yersinia pestis T3SS. GSK-tagged YopE, YopH, LcrQ, YopK, YopN, and YopJ were efficiently phosphorylated when translocated into HeLa cells. Similarly, the injection of GSK-CagA by the Helicobacter pylori T4SS into different cell types was measured via phosphorylation of the GSK tag. The GSK tag provides a simple method to monitor the translocation of T3S and T4S substrates.

The neurological disorder associated with thyroid autoimmunity is an elusive disease that neurologists have learned to recognize in the last few years. The diagnosis is made, after excluding more common diseases, when neuropsychiatric symptoms develop in a patient with high serum concentrations of anti-thyroid antibodies. The clinical presentations of the disease and the many controversial issues surrounding the diagnosis, the pathogenesis, the role of thyroid autoantibodies, and the choice of therapy are reviewed and discussed in the light of the medical literature in English.

Summary Secretion of Yop effector proteins by the Yersinia pes- tis plasmid pCD1-encoded type III secretion system (T3SS) is regulated in response to specific environ- mental signals. Yop secretion is activated by contact with a eukaryotic cell or by growth at 37 ∞ C in the absence of calcium. The secreted YopN protein, the SycN/YscB chaperone and TyeA form a cytosolic YopN/SycN/YscB/TyeA complex that is required to prevent Yop secretion in the presence of calcium and prior to contact with a eukaryotic cell. The mechanism by which these proteins prevent secretion and the subcellular location where the block in secretion occurs are not known. To further investigate both the mechanism and location of the YopN-dependent block, we isolated and characterized several YopN mutants that constitutively block Yop secretion. All the identified amino-acid substitutions that resulted in a constitutive block in Yop secretion mapped to a central domain of YopN that is not directly involved in the interaction with the SycN/YscB chaperone or TyeA. The YopN mutants required an intact TyeA-bind- ing domain and TyeA to block secretion, but did not require an N-terminal secretion signal, an intact chap- erone-binding domain or the SycN/YscB chaperone. These results suggest that a C-terminal domain of YopN complexed with TyeA blocks Yop secretion from a cytosolic, not an extracellular, location. A hypothet- ical model for how the YopN/SycN/YscB/TyeA com- plex regulates Yop secretion is presented.

Summary Yersinia pestis , the causative agent of plague, exports a set of virulence proteins called Yops upon contact with eukaryotic cells. A subset of these Yops is trans- located directly into the cytosol of host cells. In this study, a novel protein tag-based reporter system is used to measure the translocation of Yops into cul- tured eukaryotic cells. The reporter system uses a small bipartite phosphorylatable peptide tag, termed the Elk tag. Translocation of an Elk-tagged protein into eukaryotic cells results in host cell protein kinase- dependent phosphorylation of the tag at a specific serine residue, which can subsequently be detected with phosphospecific antibodies. The YopN, TyeA, SycN, YscB and LcrG proteins function to prevent Yop secretion before host cell contact. The role of these proteins was investigated in the translocation of Elk- tagged YopE (YopE 129 -Elk) and YopN (YopN 293 -Elk) into HeLa cells. Y. pestis yopN , tyeA , sycN and yscB dele- tion mutants showed reduced levels of YopE 129 -Elk phosphorylation compared with the parent strain, indicating that these mutants translocate reduced amounts of YopE. We also demonstrate that YopN 293 - Elk is translocated into HeLa cells and that this pro- cess is more efficient in a Yersinia yop polymutant strain lacking the six translocated effector Yops. Y. pestis sycN and yscB mutants translocated reduced amounts of YopN 293 -Elk; however, tyeA and lcrG mutants translocated higher amounts of YopN 293 -Elk compared with the parent strain. These data suggest that TyeA and LcrG function to suppress the secretion

Our research in the past few years has identified B cell–specific biomarkers able to predict optimal Ab responses in both young and elderly individuals. These biomarkers are activation-induced cytidine deaminase (AID), the enzyme of class switch recombination and somatic hypermutation; the transcription factor E47, crucial for AID expression; and the ability to generate optimal memory B cells. Moreover, we have found that the increased proinflammatory status of the elderly, both in sera and intrinsic to B cells, negatively impacts B cell function. We have now investigated whether particular inflammatory microRNAs (miRs) contribute to decreased E47 and AID in aged B cells. Our data indicate that E47 and AID mRNA stability is lower in stimulated B cells from elderly individuals. We measured the expression of two miRs crucial for class switch recombination, miR-155 and miR-16, in human unstimulated B cells from young and elderly individuals with the rationale that increases in these before stimulation would decrease E47/AID upon cell activation. We found these miRs and B cell–intrinsic inflammation upregulated in aged unstimulated B cells and negatively associated with AID in the same B cells after stimulation with CpG. We propose that the downregulation of AID in aged human B cells may occur through binding of miR-155 to the 3′-untranslated regions of AID mRNA and/or binding of miR-16 to the 3′-untranslated regions of E47 mRNA, as well as at the transcriptional level of less E47 for AID. Our results indicate novel molecular pathways leading to reduced B cell function with aging.

Gram-negative bacteria use type III secretion (TTS) systems to translocate proteins into the extracellular environment or directly into eukaryotic cells. These complex secretory systems are assembled from over 20 different structural proteins, including 10 that have counterparts in the flagellar export pathway. Secretion substrates are directed to the TTS machinery via mRNA and/or amino acid secretion signals. TTS chaperones bind to select secretion substrates and assist in the export process. Recent progress in the understanding of TTS is reviewed.

An unusual case of brachial plexopathy following an alcohol binge is presented. The patient developed numbness and weakness of his right hand and neurophysiological tests demonstrated that the lesion level was at the brachial plexus. MRI of the brachial plexus, cerebrospinal fluid examination and DNA analysis for hereditary neuropathy with liability to pressure palsies were normal. Repeated neurological examination and neurophysiological studies 60 days later were normal. A diagnosis of brachial plexus neuropathy consequent to non-traumatic stretching of the middle and the lower trunks was made.

Many skin infections are caused by Staphylococcus aureus, a bacterial pathogen that produces virulence factors associated with these conditions such as exfoliative toxins A and B (ETA, ETB) and the leukotoxin Panton–Valentine leukocidin (PVL). Herein, we examine the potential of skin-infecting S. aureus to produce virulence factors and their impact on the local immune response. Toxin gene profiles were generated from 188 S. aureus isolated as single infecting organisms from skin lesions and demonstrated a higher potential to express ETA, ETB, and PVL than community isolates (p

In some definite patients, a standard neurophysiological tool may not solve a complete differential diagnosis in common nerve peroneal neuropathy. In this study we have assessed a new simple procedure to study the orthodromic sensory conduction of both the superficial peroneal nerves (SPN) and deep peroneal nerves (DPN) in a heterogeneous group of 55 normal subjects. The mean sensory orthodromic conduction velocity of the SPN was 58.35 m/s. The mean sensory orthodromic conduction velocity of the mixed nerve action potential (MNAP) of the DPN was 55.27 m/s. The sensory conduction velocity, the amplitude of sensory-evoked potentials of SPN and DPN across the fibular head and the normative values are discussed. Our results confirm that these recording methods are easy to repeat and reliable in identifying peroneal neuropathy.

The localization and membrane topology of the Yersinia pestis YscJ lipoprotein, an essential component of the type III secretion apparatus, was investigated. YscJ was demonstrated to be an inner membrane (IM) lipoprotein that is anchored to the periplasmic face of the IM via an N-terminal lipid moiety and via a C-terminal transmembrane (TM) domain. Localization of the N-terminal lipid moiety to the IM occurred regardless of the amino-acid residues found in the +2 or +3 positions. IM localization was dependent upon an intact N-terminal domain (amino acids +1 to +61), suggesting that this region plays a role in YscJ localization. In contrast, the YscJ C-terminal domain and TM domain were not required for IM localization. N-terminal sequence analysis demonstrated that a significant proportion of membrane-localized YscJ lacks N-acylation, the final modification required for Lol-dependent transport of a lipoprotein to the OM. Interestingly, attachment of the N-terminus to the IM was required for YscJ function; however, the YscJ secretion signal and lipo-box could be functionally replaced by the first TM domain of the YscV protein, suggesting that the mechanism of attachment to the IM was not critical.

Post-malaria neurological syndrome (PMNS) is a rare complication of malaria. It follows recovery from an episode of Plasmodium falciparum malaria and is characterised by symptoms and signs of encephalopathy. Patients usually improve without any specific treatment. The pathogenesis is unknown, but it is probably immunologically mediated. The objective of this case study is to describe the first Italian patient with PMNS. A 60-year-old Italian man developed acute P. falciparum malaria after a stay in French Guinea. Twenty days after recovering from malaria, he became confused, developed generalised weakness, limb tremors, shivering and dizziness. These symptoms continued for three days, then resolved spontaneously. Neuroimaging was normal. Cerebrospinal fluid analysis revealed breakdown of the blood/brain barrier, without oligoclonal bands and normal IgG index. Our patient presented a mild diffuse encephalopathy suggestive of a generic activation of the immune system without any specific reaction against antigens within the CNS.

Secretion of Yop effector proteins by the Yersinia pestis plasmid pCD1-encoded type III secretion system (T3SS) is regulated in response to specific environmental signals. Yop secretion is activated by contact with a eukaryotic cell or by growth at 37 degrees C in the absence of calcium. The secreted YopN protein, the SycN/YscB chaperone and TyeA form a cytosolic YopN/SycN/YscB/TyeA complex that is required to prevent Yop secretion in the presence of calcium and prior to contact with a eukaryotic cell. The mechanism by which these proteins prevent secretion and the subcellular location where the block in secretion occurs are not known. To further investigate both the mechanism and location of the YopN-dependent block, we isolated and characterized several YopN mutants that constitutively block Yop secretion. All the identified amino-acid substitutions that resulted in a constitutive block in Yop secretion mapped to a central domain of YopN that is not directly involved in the interaction with the SycN/YscB chaperone or TyeA. The YopN mutants required an intact TyeA-binding domain and TyeA to block secretion, but did not require an N-terminal secretion signal, an intact chaperone-binding domain or the SycN/YscB chaperone. These results suggest that a C-terminal domain of YopN complexed with TyeA blocks Yop secretion from a cytosolic, not an extracellular, location. A hypothetical model for how the YopN/SycN/YscB/TyeA complex regulates Yop secretion is presented.

Background: Hashimoto's encephalopathy (HE) is a condition believed to complicate Hashimoto's thyroiditis (HT). The diagnosis is suspected in the presence of high levels of serum anti-thyroid antibodies. We have recently demonstrated that in patients with HE there is an intrathecal synthesis of anti-thyroid antibodies, and concluded that the diagnosis of HE should be based on this cerebrospinal fluid (CSF) finding. Objective: getting an estimate of the prevalence of the disease, verifying the association with HT and investigating the pathogenetic role of anti-thyroid antibodies. Methods: 34-months prospective study in a hospital setting serving a community of 150,000 people. Patients with unexplained symptoms of acute or subacute encephalopathy or myelopathy or with a history of thyroid disorders were selected for the measurement of anti-thyroid antibodies. In the presence of high serum levels of autoantibodies, the same tests were performed in the CSF. Results: Twelve patients had increased concentrations of serum autoantibodies but HE was diagnosed only in nine patients. The estimated prevalence of HE is 2.1/100,000. Only six HE patients had also HT. Four patients received corticosteroids, five patients were not treated. Five patients improved, four patients spontaneously, one patient after corticosteroids. Repeated CSF examinations showed that the titer of CSF autoantibodies did not correlate with the clinical stage of the disease nor was influenced by corticosteroids. In addition, the course of symptoms was independent of therapy. Conclusions: The association of encephalopathy and high titers of anti-thyroid antibodies is not sufficient to make a diagnosis of HE. Independent of the clinical status of the thyroid gland, the intrathecal synthesis of autoantibodies is a distinctive marker of this elusive condition.

Yersinia pestis, the causative agent of plague, exports a set of virulence proteins called Yops upon contact with eukaryotic cells. A subset of these Yops is translocated directly into the cytosol of host cells. In this study, a novel protein tag-based reporter system is used to measure the translocation of Yops into cultured eukaryotic cells. The reporter system uses a small bipartite phosphorylatable peptide tag, termed the Elk tag. Translocation of an Elk-tagged protein into eukaryotic cells results in host cell protein kinase-dependent phosphorylation of the tag at a specific serine residue, which can subsequently be detected with phosphospecific antibodies. The YopN, TyeA, SycN, YscB and LcrG proteins function to prevent Yop secretion before host cell contact. The role of these proteins was investigated in the translocation of Elk-tagged YopE (YopE129-Elk) and YopN (YopN293-Elk) into HeLa cells. Y. pestis yopN, tyeA, sycN and yscB deletion mutants showed reduced levels of YopE129-Elk phosphorylation compared with the parent strain, indicating that these mutants translocate reduced amounts of YopE. We also demonstrate that YopN293-Elk is translocated into HeLa cells and that this process is more efficient in a Yersinia yop polymutant strain lacking the six translocated effector Yops. Y. pestis sycN and yscB mutants translocated reduced amounts of YopN293-Elk; however, tyeA and lcrG mutants translocated higher amounts of YopN293-Elk compared with the parent strain. These data suggest that TyeA and LcrG function to suppress the secretion of YopN before host cell contact, whereas SycN and YscB facilitate YopN secretion and subsequent translocation.

To report and discuss the neuropsychological deficits and neuroimaging findings in a patient with probable Marchiafava-Bignami disease.A right-handed woman with chronic alcoholism demonstrated mutism, impaired comprehension of spoken language, alexia, and right-handed agraphia. The syndrome of interhemispheric disconnection was manifested by left-handed deficit of constructional ability and agraphia. The patient underwent brain computed tomographic scans, technetium 99 hexylmethylpropylene amineoxime-single photon emission computed tomography, and magnetic resonance imaging (MRI) that also included fluid attenuated inversion recovery images.Clinical neurology department.The patient's symptoms were related to scattered lesions of the corpus callosum and to extensive symmetrical lesions of the centrum semiovale. Only the latter were detected by computed tomographic scans. Results of single photon emission computed tomography did not show areas of focal hypoperfusion. Results of fast spinecho MRI showed all lesions were hyperintense in T1-weighted images and hypointense in T2-weighted images. Fluid attenuated inversion recovery images revealed that periventricular lesions had a hypointense core surrounded by a hyperintense rim; callosal lesions were still hyperintense.We believe that our patient's symptoms are due to the discontinuous affection of the corpus callosum and to the bilateral cutting of the outflow from the cortex. The MRI findings may be interpreted as indicating central necrosis and peripheral demyelination of periventricular lesions and demyelination of the corpus callosum. The combined use of fast spin echo and fluid attenuated inversion recovery MRI reproduced with more accuracy than fast spin echo MRI alone some features of Marchiafava-Bignami disease known from observations at autopsy.