NFAT5 counters long-term IFN-I responses in hematopoietic stem cells to preserve reconstitution potential.

Hematopoietic stem cells (HSCs) readily recover from acute stress, but persistent stress can reduce their viability and long-term potential. Here we show that the nuclear factor of activated T cells 5 (NFAT5), a transcription modulator of inflammatory responses, protects the HSC pool under stress. NFAT5 restrains HSC differentiation to multipotent progenitors (MPPs) after bone marrow transplantation and bone marrow ablation with ionizing radiation or chemotherapy. Correspondingly, NFAT5-deficient HSCs fail to support long-term reconstitution of hematopoietic progenitors and mature blood cells after serial transplant. Evidence from competitive transplant assays shows that these defects are HSC-intrinsic. NFAT5-deficient HSCs exhibit enhanced expression of type I interferon (IFN-I) response genes after transplant, and suppressing IFN-I-receptor prevents their exacerbated differentiation and cell death after reconstitution and improves long-term regeneration potential. Blockade of IFN-I receptor also prevented the overdifferentiation of NFAT5-deficient HSCs after bone marrow ablation. These findings show that long-term IFN-I responses to different hematopoietic stressors drive HSCs towards more differentiated progenitors, and that NFAT5 has an HSC-intrinsic role limiting IFN-I responses to preserve reconstitution potential. Our identification of cell-intrinsic mechanisms that strengthen the resistance of HSCs to stress could help to devise approaches to protect long-term stemness during the treatment of hematopoietic malignancies.

Salt-Sensitive Hypertension of the Renal Tubular Cell-Specific NFAT5 (Nuclear Factor of Activated T-Cells 5) Knockout Mice.

[Figure: see text].

The transcription factor NFAT5 limits infection-induced type I interferon responses.

Type I interferon (IFN-I) provides effective antiviral immunity but can exacerbate harmful inflammatory reactions and cause hematopoietic stem cell (HSC) exhaustion; therefore, IFN-I expression must be tightly controlled. While signaling mechanisms that limit IFN-I induction and function have been extensively studied, less is known about transcriptional repressors acting directly on IFN-I regulatory regions. We show that NFAT5, an activator of macrophage pro-inflammatory responses, represses Toll-like receptor 3 and virus-induced expression of IFN-I in macrophages and dendritic cells. Mice lacking NFAT5 exhibit increased IFN-I production and better control of viral burden upon LCMV infection but show exacerbated HSC activation under systemic poly(I:C)-induced inflammation. We identify IFNß as a primary target repressed by NFAT5, which opposes the master IFN-I inducer IRF3 by binding to an evolutionarily conserved sequence in the IFNB1 enhanceosome that overlaps a key IRF site. These findings illustrate how IFN-I responses are balanced by simultaneously opposing transcription factors.

Regulation of Inflammatory Functions of Macrophages and T Lymphocytes by NFAT5.

The transcription factor NFAT5, also known as TonEBP, belongs to the family of Rel homology domain-containing factors, which comprises the NF-κB proteins and the calcineurin-dependent NFAT1 to NFAT4. NFAT5 shares several structural and functional features with other Rel-family factors, for instance it recognizes DNA elements with the same core sequence as those bound by NFAT1 to 4, and like NF-κB it responds to Toll-like receptors (TLR) and activates macrophage responses to microbial products. On the other hand, NFAT5 is quite unique among Rel-family factors as it can be activated by hyperosmotic stress caused by elevated concentrations of extracellular sodium ions. NFAT5 regulates specific genes but also others that are inducible by NF-κB and NFAT1 to 4. The ability of NFAT5 to do so in response to hypertonicity, microbial products, and inflammatory stimuli may extend the capabilities of immune cells to mount effective anti-pathogen responses in diverse microenvironment and signaling conditions. Recent studies identifying osmostress-dependent and -independent functions of NFAT5 have broadened our understanding of how NFAT5 may modulate immune function. In this review we focus on the role of NFAT5 in macrophages and T cells in different contexts, discussing findings from in vivo mouse models of NFAT5 deficiency and reviewing current knowledge on its mechanisms of regulation. Finally, we propose several questions for future research.

Revisão sistemática da profilaxia para tromboembolismo venoso após artroplastia do joelho: enoxaparina versus rivaroxabana / Systematic review of prophylaxis for venous thromboembolism after knee arthroplasty: enoxaparin versus rivaroxaban

RESUMO A artroplastia total do joelho é um procedimento eletivo, realizado em indivíduos relativamente saudáveis. Porém, devido ao risco inerente de tromboembolismo venoso, são utilizados fármacos para sua profilaxia. O objetivo do presente trabalho foi conduzir uma revisão sistemática da literatura para comparar a eficácia da enoxaparina e da rivaroxabana na prevenção desta complicação e no risco de sangramento intraoperatório. Foi feita uma revisão no site SciELO, Pubmed e Cochrane através dos descritores, artroplastia de joelho, rivaroxabana e enoxaparina através da estratégia de busca PICO. Os critérios de inclusão foram os artigos no período estudado, que comparavam ambas as drogas em cirurgias de artroplastia do joelho. Os critérios de relevância para tornar o estudo elegível foram definidos como: somente artigos publicados a partir 2010 e com casuística com mais de 20 pacientes foram considerados; somente estudos obtidos em sua íntegra foram analisados; somente estudos com seguimento maior do que 12 meses foram considerados relevantes. As variáveis utilizadas para a comparação dos artigos foram as complicações mais comuns no pós-operatório de artroplastias do joelho: tromboembolismo venoso e sangramento. Foi utilizado o Review Man 5.3 para estruturação da revisão. Os autores observaram que nos estudos analisados, considerando tromboembolismo venoso sintomático, a rivaroxabana resultou em maiores benefícios quando comparada com a enoxaparina.

ABSTRACT Total knee arthroplasty is an elective procedure performed on relatively healthy individuals. However, due to the inherent risk of venous thromboembolism, drugs are used for its prophylaxis. The objective of the present study was to conduct a systematic review of the literature to compare the efficacy of enoxaparin and rivaroxaban in preventing this complication and the risk of intraoperative bleeding. We reviewed the SciELO, Pubmed and Cochrane databases with the descriptors knee arthroplasty, rivaroxaban and enoxaparin through the PICO search strategy. Inclusion criteria were the articles during the study period comparing both drugs in knee arthroplasty. Relevant criteria to study eligibility were articles published since 2010 and with a sample of more than 20 patients; studies obtained in their entirety; and studies with follow-up of more than 12 months. The variables used to compare the articles were the most common postoperative complications of knee arthroplasties: venous thromboembolism and bleeding. We used the Review Man software, version 5.3, for structuring the review. In the studies analyzed, considering symptomatic venous thromboembolism, rivaroxaban resulted in higher benefits when compared to enoxaparin.

Macrophage-specific MHCII expression is regulated by a remote Ciita enhancer controlled by NFAT5.

MHCII in antigen-presenting cells (APCs) is a key regulator of adaptive immune responses. Expression of MHCII genes is controlled by the transcription coactivator CIITA, itself regulated through cell type-specific promoters. Here we show that the transcription factor NFAT5 is needed for expression of Ciita and MHCII in macrophages, but not in dendritic cells and other APCs. NFAT5-deficient macrophages showed defective activation of MHCII-dependent responses in CD4+ T lymphocytes and attenuated capacity to elicit graft rejection in vivo. Ultrasequencing analysis of NFAT5-immunoprecipitated chromatin uncovered an NFAT5-regulated region distally upstream of Ciita This region was required for CIITA and hence MHCII expression, exhibited NFAT5-dependent characteristics of active enhancers such as H3K27 acetylation marks, and required NFAT5 to interact with Ciita myeloid promoter I. Our results uncover an NFAT5-regulated mechanism that maintains CIITA and MHCII expression in macrophages and thus modulates their T lymphocyte priming capacity.

NFAT5-Regulated Macrophage Polarization Supports the Proinflammatory Function of Macrophages and T Lymphocytes.

Macrophages are exquisite sensors of tissue homeostasis that can rapidly switch between pro- and anti-inflammatory or regulatory modes to respond to perturbations in their microenvironment. This functional plasticity involves a precise orchestration of gene expression patterns whose transcriptional regulators have not been fully characterized. We had previously identified the transcription factor NFAT5 as an activator of TLR-induced responses, and in this study we explore its contribution to macrophage functions in different polarization settings. We found that both in classically and alternatively polarized macrophages, NFAT5 enhanced functions associated with a proinflammatory profile such as bactericidal capacity and the ability to promote Th1 polarization over Th2 responses. In this regard, NFAT5 upregulated the Th1-stimulatory cytokine IL-12 in classically activated macrophages, whereas in alternatively polarized ones it enhanced the expression of the pro-Th1 mediators Fizz-1 and arginase 1, indicating that it could promote proinflammatory readiness by regulating independent genes in differently polarized macrophages. Finally, adoptive transfer assays in vivo revealed a reduced antitumor capacity in NFAT5-deficient macrophages against syngeneic Lewis lung carcinoma and ID8 ovarian carcinoma cells, a defect that in the ID8 model was associated with a reduced accumulation of effector CD8 T cells at the tumor site. Altogether, detailed analysis of the effect of NFAT5 in pro- and anti-inflammatory macrophages uncovered its ability to regulate distinct genes under both polarization modes and revealed its predominant role in promoting proinflammatory macrophage functions.

Necrolisis epidérmica tóxica: un paradigma de enfermedad crítica / Toxic epidermal necrolysis: a paradigm of critical illness

RESUMEN La necrolisis epidérmica tóxica es una reacción cutánea adversa de tipo inmunológico secundaria en la mayor parte de los casos a la administración de un fármaco. La necrolisis epidérmica tóxica, el síndrome de Steven Johnson y el eritema exudativo multiforme forman parte del mismo espectro de enfermedad. La mortalidad de la necrolisis epidérmica tóxica es alrededor del 30%. La fisiopatología de la necrolisis epidérmica tóxica es semejante en muchos aspectos a la de las quemaduras dérmicas superficiales. La afectación mucosa del epitelio ocular y genital se asocia con secuelas graves si no se trata de forma temprana. Se acepta en general que los pacientes con necrolisis epidérmica tóxica son tratados mejor en unidades de grandes quemados, donde existe experiencia en el manejo de enfermos con pérdida cutánea extensa. El tratamiento es de soporte, eliminación y cobertura con derivados biosintéticos de la piel de las zonas afectadas, tratamiento de la afectación mucosa, y tratamiento inmunosupresor específico. De los tratamientos ensayados sólo se usa actualmente en la mayor parte de los centros la inmunoglobulina G y la ciclosporina A, aun cuando no existe evidencia sólida para recomendar ningún tratamiento específico. Entre los aspectos particulares del tratamiento de esta enfermedad se encuentra la prevención de secuelas relacionadas con la formación de sinequias, los cuidados oculares para prevenir secuelas graves que pueden conducir a la ceguera, y el tratamiento específico inmunosupresor. Un mejor conocimiento de los principios del manejo de la necrolisis epidérmica tóxica llevará a un mejor manejo de la enfermedad, a una mayor supervivencia y una menor prevalencia de las secuelas.

ABSTRACT Toxic epidermal necrolysis is an adverse immunological skin reaction secondary in most cases to the administration of a drug. Toxic epidermal necrolysis, Stevens-Johnson syndrome, and multiform exudative erythema are part of the same disease spectrum. The mortality rate from toxic epidermal necrolysis is approximately 30%. The pathophysiology of toxic epidermal necrolysis is similar in many respects to that of superficial skin burns. Mucosal involvement of the ocular and genital epithelium is associated with serious sequelae if the condition is not treated early. It is generally accepted that patients with toxic epidermal necrolysis are better treated in burn units, which are experienced in the management of patients with extensive skin loss. Treatment includes support, elimination, and coverage with biosynthetic derivatives of the skin in affected areas, treatment of mucosal involvement, and specific immunosuppressive treatment. Of the treatments tested, only immunoglobulin G and cyclosporin A are currently used in most centers, even though there is no solid evidence to recommend any specific treatment. The particular aspects of the treatment of this disease include the prevention of sequelae related to the formation of synechiae, eye care to prevent serious sequelae that can lead to blindness, and specific immunosuppressive treatment. Better knowledge of the management principles of toxic epidermal necrolysis will lead to better disease management, higher survival rates, and lower prevalence of sequelae.

Cervical cancer screening cotesting with cytology and MRNA HPV E6/E7 yields high rates of CIN2+ lesions in young women.

BACKGROUND: European guidelines recommend primary HPV testing for cervical cancer screening. However, the starting age remains to be defined, with an undecided window between 30 and 35 years. This pilot study compares the effectiveness of primary HPV testing to that of cytology for the detection of high-grade (CIN2+) lesions stratified by age. METHODS: Cotesting with LBC cytology and APTIMA® HPV (AHPV) was performed in 5053 women aged 25-65 in an opportunistic screening program in Madrid. AHPV-positive cases were referred to colposcopy and genotyped for HPV16 and 18/45 (AHPV-GT). Results were analyzed stratified in four age groups. RESULTS: 454 cases (9.0%) were AHPV-positive. Women under 35 had a 30.2% CIN2+ rate, compared to 21.9% and 20.4% for women aged 35-44 or 45-54. There was a significant increase (P < .05) in the rate of CIN2+ in AHPV-GT-positive women when compared to that for other HPV types (AHPV-other), being 43.3% versus 15.7%. AHPV-GT-positive women under 35 had significantly higher rates of CIN2+ lesions than any other age-group. The sensitivity of cytology for cervical CIN2+ in APHV-positive women was 60.6%. All 4 carcinomas, including one AHPV-negative endometrial adenocarcinoma, had abnormal cytology. All cervical CIN2+ lesions biopsied were AHPV-positive. CONCLUSIONS: Aptima HPV shows a significantly higher sensitivity for cervical CIN2+ lesions than cytology alone. Unexpectedly, AHPV-positive women under 35 had the highest incidence of CIN2+ lesions, particularly when they are HPV16/18/45-positive. Reconsidering HPV primary screening before the recommended age of 35 is warranted.

Increased risk of malignancy for non-atypical urothelial cell groups compared to negative cytology in voided urine. Morphological changes with LBC.

Liquid-based cytology (LBC) has recently become the preferred method for urine cytology analysis, but differences with conventional cytology (CC) have been observed. The purpose of this study is to analyze these differences and the clinical relevance of non-atypical urothelial cell groups (UCG) in voided urine specimens. Reporting terminology is discussed. Initially, diagnostic categories from 619 LBC and 474 CC samples, reviewed by five different pathologists, were compared (phase 1). Five years after LBC was implemented and applying strict cytologic criteria for UCG diagnosis, 760 samples were analyzed (phase 2) and compared to previous LBC specimens. Diagnostic differences, interobserver variability and clinicopathological correlation with a 6-month follow-up, were analyzed. UCG increased from 6.5% with CC to 20.7% (218%, 3.2 fold, P < 0.0001) with LBC. This difference was not related to interobserver variability. Five years later, the rate of UCG had decreased to 13 2%. While 6% of cases with a negative cytology had urothelial carcinoma (UC) within 6 months of diagnosis, this percentage increased to 15.7% with UCG. The sensitivity of the UCG category for UC was low (30.4%), but the specificity and the negative predictive value (NPV) were high (87.1% and 94%, respectively). LBC increases UCG when compared to CC. This can be corrected with observers experience and using set cytological criteria. Due to its association with carcinoma, the presence of UCG in voided urine should be framed in a diagnostic category other than "negative for malignancy." Diagn. Cytopathol. 2016;44:582-590. © 2016 Wiley Periodicals, Inc.

Cytological Diagnosis of Bilateral Breast Implant-Associated Lymphoma of the ALK-Negative Anaplastic Large-Cell Type. Clinical Implications of Peri-Implant Breast Seroma Cytological Reporting.

The cytological examination of peri-prosthetic breast effusions allowed the diagnosis of bilateral breast-implant ALK-negative anaplastic large cell lymphoma (BI-ALCL) in the case reported. Ten years after reconstructive surgery with bilateral breast implants, a large unilateral seroma developed and was cytologically analyzed. The presence of CD30 and CD4-positive large-sized atypical lymphoid cells exhibiting horseshoe-shaped nuclei and a brisk mitotic activity rendered the diagnosis of BI-ALCL. Similar cells were seen in the peri-prosthetic fluid intraoperatively collected from the contralateral breast. Although initial histological analysis of the capsulectomy specimens showed unilateral tumor, the cytological findings prompted a more thorough tissue sampling, resulting in the diagnosis of bilateral disease. BI-ALCL usually follows an indolent clinical course; however, there are reported cases with an aggressive behavior. While the presence of bilateral disease is a putative risk factor for a bad prognosis, the small number of cases reported precludes a definitive assessment of this risk. Since most BI-ALCL present with late seromas, cytologic analysis of these effusions in women with breast implants should be mandatory. Cytology is a safe tool for diagnosis and follow-up of patients with breast implant-related late seromas, sometimes proven more sensitive than histological analysis. Complete bilateral capsulectomy and a detailed histological analysis should follow a cytological diagnosis of BI-ALCL in a breast effusion in order to avoid false negative diagnoses. Our case constitutes the first published report of a bilateral BI-ALCL diagnosed by cytology. Diagn. Cytopathol. 2016;44:623-627. © 2016 Wiley Periodicals, Inc.

Clear Cell Atypical Fibroxanthoma: Clinicopathological Study of 6 Cases and Review of the Literature With Special Emphasis on the Differential Diagnosis.

Atypical fibroxanthoma (AFX) is an uncommon dermal-based neoplasm arising on the sun-damaged skin of elderly people. Clear cell AFX is a rare variant with only 12 cases reported until the present date, all of them as case reports, except for 1 small series of 3 cases. The authors report 6 new cases and review the literature with special emphasis on the differential diagnosis. The clear cell variant represents 5% of AFX from their files. Histopathologically, it consists of sheets of epithelioid, pleomorphic cells, intermixed with a varying number of giant multinucleated and spindle cells, the latter arranged in a fascicular pattern. All cell types predominantly exhibit a clear, microvacuolated cytoplasm with well-demarcated cell borders. The clinical and immunohistochemical features of this variant are similar to those of the classic type. Clear cell AFX must be differentiated from other cutaneous clear cell neoplasms, some of them with an aggressive clinical behavior, including clear cell melanoma, primary cutaneous and metastatic clear cell carcinomas, clear cell sarcoma, pleomorphic liposarcoma, tumor of perivascular epithelioid cells, and distinctive dermal clear cell mesenchymal neoplasm. The clinical presentation and immunohistochemical profile play a key role in the differential diagnosis.

Statistical analysis on the concordance of the radiological evaluation of fractures of the distal radius subjected to traction / Análise estatística da concordância na avaliação radiológica das fraturas de rádio distal submetidas a tração

The objective of this study was to evaluate the current classifications for fractures of the distal extremity of the radius, since the classifications made using traditional radiographs in anteroposterior and lateral views have been questioned regarding their reproducibility. In the literature, it has been suggested that other options are needed, such as use of preoperative radiographs on fractures of the distal radius subjected to traction, with stratification by the evaluators. The aim was to demonstrate which classification systems present better statistical reliability. RESULTS: In the Universal classification, the results from the third-year resident group (R3) and from the group of more experienced evaluators (Staff) presented excellent correlation, with a statistically significantp-value (p < 0.05). Neither of the groups presented a statistically significant result through the Frykman classification. In the AO classification, there were high correlations in the R3 and Staff groups (respectively 0.950 and 0.800), withp-values lower than 0.05 (respectively <0.001 and 0.003). CONCLUSION: It can be concluded that radiographs performed under traction showed good concordance in the Staff group and in the R3 group, and that this is a good tactic for radiographic evaluations of fractures of the distal extremity of the radius.

Avaliar as classificações atuais da fratura da extremidade distal do rádio, pois as classificações feitas em radiografias tradicionais nas incidências anteroposterior e perfil têm sido questionadas quanto a sua reprodutibilidade e é sugerida pela literatura a necessidade de outras opções, com o uso das radiografias pré-operatórias submetidas a tração de fraturas de rádio distal, estratificados pelos avaliadores, com vistas a demonstrar quais classificações apresentam melhor confiabilidade estatística. RESULTADOS: Na classificação Universal os resultados dos grupos de R3 e Staff apresentaram uma ótima correlação, com um p-valor estatisticamente significativo (p < 0,05). Quando avaliada a classificação de Frykman, nenhum grupo apresentou um resultado estatisticamente significativo. Na classificação AO, nos grupos R3 e Staff, a correlação foi alta (respectivamente 0,950 e 0,800) com um p-valor abaixo de 0,05 (respectivamente < 0,001 e 0,003). CONCLUSÃO: A tração para feitura das radiografias se mostrou com uma boa concordância principalmente nos grupos avaliadores de maior experiência (Staff) e no residente de 3 o ano e é uma boa tática na avaliação radiográfica da fratura da extremidade distal do rádio.

Pleomorphic dermal sarcoma: a more aggressive neoplasm than previously estimated.

BACKGROUND: Pleomorphic dermal sarcoma (PDS) is a rare neoplasm sharing pathological features with atypical fibroxanthoma, but adding tumor necrosis, invasion beyond superficial subcutis or vascular or perineural infiltration. Although its metastatic risk has been estimated to be less than 5%, its real outcome is presently uncertain because of its rarity and to the lack of homogeneous criteria used in reported cases. METHODS: Retrospective clinicopathological study of 18 cases of PDS. RESULTS: The lesions presented as tumors or plaques (size: 7-70 mm) on the head of elderly patients (median: 81 years), without a gender predominance. Histopathologically, they consisted of spindle cells arranged in a fascicular pattern, containing pleomorphic epithelioid and giant multinucleated cells in varying proportions, and usually exhibiting numerous mitotic figures and infiltrative tumor margins. No immunoexpression for cytokeratins, S100 protein, desmin or CD34 was observed. Necrosis and venous invasion were found in three tumors each (17%). Follow-up was available in 15 cases (median: 33 months). Three patients (20%) had local recurrences, all with incomplete primary surgical resections. Three patients (20%) developed distant metastases in the skin, regional lymph nodes and/or lungs and died from the disease. CONCLUSION: Our data suggest that PDS may be a more aggressive neoplasm than previously estimated.

Daniel Alcides Carrión: una visión funcional / Daniel Alcides Carrión: a functional view

Se hace la consideración de Daniel Alcides Carrión, héroe de la Medicina peruana y de la Nación, desde el punto de vista fenomenológico, tanto filosófico como psicológico, considerando más la visión social que un fenómeno individual, bajo las influencias de las corrientes de pensamiento vigentes a fines del siglo XIX. Tanto el romanticismo como el positivismo fueron de origen europeo, pero influenciaron definitivamente en el Perú en la época de Carrión y, seguramente, tuvieron que ver en gran medida con su decisión a la autoexperimentación. Se hace especial mención a su rol pionero como investigador clínico y se remarca la necesidad de completar aquellos acontecimientos que formaron parte del funcionamiento del héroe en el tiempo histórico correspondiente...

A close vision is directed towards Daniel Alcides Carrión, hero of the Peruvian Medicine and the nation, from the point of view of phenomenology, both philosophical and psychological, considering more like a social vision that an individual phenomenon, under the influence of currents of thought prevailing at the late nineteenth century. Both romanticism and positivism were of European origin but definitely influenced in Peru at the time of Carrion and certainly had largely to do with his decision to self-experimentation. Special mention to its pioneering role is made as a clinical researcher and the need to complete those events that were part of the operation of the hero in the corresponding historical period...

Transcriptional regulation of the stress response by mTOR.

The kinase mammalian target of rapamycin (mTOR) is a central regulator of cell growth and proliferation that integrates inputs from growth factor receptors, nutrient availability, intracellular ATP (adenosine 5'-triphosphate), and a variety of stressors. Since early works in the mid-1990s uncovered the role of mTOR in stimulating protein translation, this kinase has emerged as a rather multifaceted regulator of numerous processes. Whereas mTOR is generally activated by growth- and proliferation-stimulating signals, its activity can be reduced and even suppressed when cells are exposed to a variety of stress conditions. However, cells can also adapt to stress while maintaining their growth capacity and mTOR function. Despite knowledge accumulated on how stress represses mTOR, less is known about mTOR influencing stress responses. In this review, we discuss the capability of mTOR, in particular mTOR complex 1 (mTORC1), to activate stress-responsive transcription factors, and we outline open questions for future investigation.

The movement protein (NSm) of Tomato spotted wilt virus is the avirulence determinant in the tomato Sw-5 gene-based resistance.

The avirulence determinant triggering the resistance conferred by the tomato gene Sw-5 against Tomato spotted wilt virus (TSWV) is still unresolved. Sequence comparison showed two substitutions (C118Y and T120N) in the movement protein NSm present only in TSWV resistance-breaking (RB) isolates. In this work, transient expression of NSm of three TSWV isolates [RB1 (T120N), RB2 (C118Y) and non-resistance-breaking (NRB)] in Nicotiana benthamiana expressing Sw-5 showed a hypersensitive response (HR) only with NRB. Exchange of the movement protein of Alfalfa mosaic virus (AMV) with NSm supported cell-to-cell and systemic transport of the chimeric AMV RNAs into N. tabacum with or without Sw-5, except for the constructs with NBR when Sw-5 was expressed, although RB2 showed reduced cell-to-cell transport. Mutational analysis revealed that N120 was sufficient to avoid the HR, but the substitution V130I was required for systemic transport. Finally, co-inoculation of RB and NRB AMV chimeric constructs showed different prevalence of RB or NBR depending on the presence or absence of Sw-5. These results indicate that NSm is the avirulence determinant for Sw-5 resistance, and mutations C118Y and T120N are responsible for resistance breakdown and have a fitness penalty in the context of the heterologous AMV system.

Two basic (hydrophilic) regions in the movement protein of Parietaria mottle virus have RNA binding activity and are required for cell-to-cell transport.

The movement protein (MP) of parietaria mottle virus (PMoV) is required for virus cell-to-cell movement. Bioinformatics analysis identified two hydrophilic non-contiguous regions (R1 and R2) rich in the basic amino acids lysine and arginine and with the predicted secondary structure of an α-helix. Different approaches were used to determine the implication of the R1 and R2 regions in RNA binding, plasmodesmata (PD) targeting and cell-to-cell movement. EMSA (Electrophoretic Mobility Shift Assay) showed that both regions have RNA-binding activity whereas that mutational analysis reported that either deletion of any of these regions, or loss of the basic amino acids, interfered with the viral intercellular movement. Subcellular localization studies showed that PMoV MP locates at PD. Mutants designed to impeded cell-to-cell movement failed to accumulate at PD indicating that basic residues in both R1 and R2 are critical for binding the MP at PD.

NFAT5 induction by the pre-T-cell receptor serves as a selective survival signal in T-lymphocyte development.

The Rel-like transcription factors nuclear factor kappa B (NF-κB) and the calcineurin-dependent nuclear factor of activated T cells (NFATc) control specific points of thymocyte maturation. Thymocytes also express a distinct member of the Rel family, the calcineurin-independent, osmostress response regulator NFAT5. Here we show that IKKß regulates the expression of NFAT5 in thymocytes, which in turn contributes to the survival of T-cell receptor αß thymocytes and the transition from the ß-selection checkpoint to the double-positive stage in an osmostress-independent manner. NFAT5-deficient thymocytes had normal expression and proximal signaling of the pre-T-cell receptor but exhibited a partial defect in ß-chain allelic exclusion and increased apoptosis. Further analysis showed that NFAT5 regulated the expression of the prosurvival factors A1 and Bcl2 and attenuated the proapoptotic p53/Noxa axis. These findings position NFAT5 as a target of the IKKß/NF-κB pathway in thymocytes and as a downstream effector of the prosurvival role of the pre-T-cell receptor.

Myxoinflammatory fibroblastic sarcoma of the face.

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare low-grade tumor of modified fibroblasts, with tendency to local recurrence. This unusual entity typically presents as a slow-growing painless mass in the distal extremities of middle-aged subjects. A 48-year-old woman presented to our clinic with a painless subcutaneous mass in the right temporal region. Excisional biopsy made the rare diagnosis of MIFS. Histologic examination showed the unique features that characterize this lesion: a myxoid component with a superimposed inflammatory infiltrate and the presence of distinctive, large, and bizarre Reed-Stemberg-like cells. A second wide tumor bed resection was performed, achieving clear margins. No adjuvant therapy was administered, and the patient is free of disease at 18 months postoperatively. To the best of our knowledge, this is the first reported case of MIFS presenting in the face. This adds another possibility for differential diagnoses of soft tissue tumors of the face.