Optical imaging spectroscopy for rapid, primary screening of SARS-CoV-2: a proof of concept.

Effective testing is essential to control the coronavirus disease 2019 (COVID-19) transmission. Here we report a-proof-of-concept study on hyperspectral image analysis in the visible and near-infrared range for primary screening at the point-of-care of SARS-CoV-2. We apply spectral feature descriptors, partial least square-discriminant analysis, and artificial intelligence to extract information from optical diffuse reflectance measurements from 5 µL fluid samples at pixel, droplet, and patient levels. We discern preparations of engineered lentiviral particles pseudotyped with the spike protein of the SARS-CoV-2 from those with the G protein of the vesicular stomatitis virus in saline solution and artificial saliva. We report a quantitative analysis of 72 samples of nasopharyngeal exudate in a range of SARS-CoV-2 viral loads, and a descriptive study of another 32 fresh human saliva samples. Sensitivity for classification of exudates was 100% with peak specificity of 87.5% for discernment from PCR-negative but symptomatic cases. Proposed technology is reagent-free, fast, and scalable, and could substantially reduce the number of molecular tests currently required for COVID-19 mass screening strategies even in resource-limited settings.

IL6/sIL6R regulates TNFα-inflammatory response in synovial fibroblasts through modulation of transcriptional and post-transcriptional mechanisms.

INTRODUCTION: The clinical efficacy of specific interleukin-6 inhibitors has confirmed the central role of IL6 in rheumatoid arthritis (RA). However the local role of IL6, in particular in synovial fibroblasts (SF) as a direct cellular target to IL6/sIL6R signal is not well characterized. The purpose of the study was to characterize the crosstalk between TNFα and IL6/sIL6R signaling to the effector pro-inflammatory response of SF. METHODS: SF lines were stimulated with either TNFα, IL6/sIL6R, or both together, for the time and dose indicated for each experiment, and where indicated, cells were treated with inhibitors actinomycin D, adalimumab, ruxolitinib and cycloheximide. mRNA expression of cytokines, chemokines and matrix metalloproteases (MMPs) were analyzed by quantitative RT-PCR. Level of IL8/CXCL8 and CCL8 in culture supernatants was measured by ELISA. Mononuclear and polymorphonuclear cells migration assays were assessed by transwell using conditioned medium from SF cultures. Statistical analyses were performed as indicated in the corresponding figure legends and a p-value < 0.05 was considered statistically significant. RESULTS: The stimulation of SF with IL6/sIL6R and TNFα, cooperatively promotes the expression of mono- and lymphocytic chemokines such as IL6, CCL8 and CCL2, as well as matrix degrading enzymes such as MMP1, while inhibiting the induction of central neutrophil chemokines such as IL8/CXCL8. These changes in the pattern of chemokines expression resulted in reduced polymorphonuclear (PMN) and increased mononuclear cells (MNC) chemoattraction by SF. Mechanistic analyses of the temporal expression of genes demonstrated that the cooperative regulation mediated by these two factors is mostly induced through de novo transcriptional mechanisms activated by IL6/sIL6R. Furthermore, we also demonstrate that TNFα and IL6/sIL6R cooperation is partially mediated by the expression of secondary factors signaling through JAK/STAT pathways. CONCLUSIONS: These results point out to a highly orchestrated response to IL6 in TNFα-induced SF and provide additional insights into the role of IL6/sIL6R in the context of RA, highlighting the contribution of IL6/sIL6R to the interplay of SF with other inflammatory cells.

Expression analysis of ethylene synthesis and signalling genes in kiwifruit stigmatic arms and their involvement in programmed cell death processes.

Kiwifruit (Actinidia chinensis var. deliciosa (A. Chev) A. Chev.) is a widely cultivated crop due to the nutritional value of its fruits. Its commercialization is related to the fruit size, which is directly linked with the number of seeds and, consequently, with pollination. In this dioecious species pollination is dependent on a short effective pollination period which is related to a Programmed Cell Death (PCD) process. At the same time, this PCD process allows the growth of many pollen tubes. Several studies suggest that ethylene can play an important role in PCD in a number of systems. In this report, we determined the full sequence of the AcACS gene, encoding the enzyme that catalyses a rate-limiting step of the ethylene synthesis. Next, we monitored the expression pattern of this gene as well as of other genes involved in ethylene synthesis (ACO2-5) and signalling (AdERS1a, AdERS1b, AdETR1, AdETR2, AdETR3, AdCTR1, AdCTR2, AdEIL1) in pollinated and non-pollinated stigmatic arms of kiwifruit female flowers. The relative expression patterns observed for AcACS, ACOs and ethylene perception and signalling genes (AdERS1, AdETR1, AdCTR1 and AdEIL1) showed that they are expressed before anthesis. After anthesis, expression of the studied genes was detected earlier in pollinated than in non-pollinated stigmatic arms, as it was previously determined for PCD hallmarks. In addition, the expression pattern of the studied genes showed a clear relationship with the PCD hallmarks described in a previous report in the secretory tissue both in non-pollinated stigmatic arms (related to the short EPP in this species) and in pollinated ones (related to the growth of many pollen tubes during progamic phase). Overall, these results suggest an involvement of ethylene with PCD contributing to the high reproductive success of this species.

Prevalence of Human Papillomavirus Genotypes in Women from Cozumel, Mexico

Background: Human papillomavirus (HPV) subtypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68 have been implicated in the development of cervical cancer (CC). These 13 high risk HPV types have been shown to be present in up to 99.7% of CC samples. In Mexico, this cancer is the leading cause of death from malignancy among women. The aim of this study was to determine the prevalence of different HPV genotypes and investigate epidemiological aspects associated with HPV infection in women from Cozumel. Material and methods: We performed an epidemiological, prospective and cross sectional study with 1,187 who accepted participation in a campaign of screening for CC, during the period 2014 to 2015. Data on epidemiological and socio-economic variables were obtained. Cervical cells were collected for detection of HPV DNA and typing of HPV-positive samples by Multiplex PCR, using a commercial kit for 16 viral genotypes. Results: The overall prevalence of HPV in women from Cozumel was 15.8 % (188/1,187), either single (13.6%) or multiple (2.19 %). The most common HPV types , in descending order of frequency, were 58 (24.5 %), 59 (13.3 %), 39 (12.2 %) and 66 (9.6 %). The most frequent high risk types were HPV-58 and -59 and of low risk HPV types the most common was HPV-6. Number of sexual partners (OR=4.78; 95% CI= 2.73-8.37; P=<0.0001) and age of first coitus (OR=0.51; 95% CI=0.32-0.81; P=<0.0011) were significantly associated with HPV infection. Conclusions: Our data indicate that the overall incidence of high risk HPV infection in Cozumel is low as compared to other studies worldwide, with a different profile of subtypes. However, as expected, risky sexual behavior was found associated with positive cases of HPV. These results highlight the need for establish strategies to prevent HPV acquisition and evaluate the impact of a vaccine application in the Cozumel population.

CD271(+) stromal cells expand in arthritic synovium and exhibit a proinflammatory phenotype.

BACKGROUND: CD271(+) stromal cells (SCs) with multipotent stem cell capacity have been identified in synovial tissues, but their functional significance is unknown. We analyzed the distribution of CD271(+) cells in inflammatory synovial tissues as well as their ex vivo immunomodulatory and inflammatory phenotypes. METHODS: CD271 expression was analyzed by immunohistochemistry in synovial tissues and by flow cytometry in primary adherent synovial cell cultures from rheumatoid arthritis (RA), osteoarthritis (OA), and non-inflammatory control tissues. Isolation of CD271(+) synovial SCs was carried out by magnetic cell sorting. Allogeneic T-cell/SC cocultures were performed to analyze the regulatory capacity of these cells on T-cell proliferation and cytokine production. The production of inflammatory mediators was analyzed in cultures of sorted CD271(+)/(-) SCs. The capacity of CD271(+)/(-) SCs to induce inflammatory cell recruitment in vivo was evaluated in subcutaneous implants in immunodeficient mice. RESULTS: CD271(+) SC were detected in non-inflammatory as well as in arthritic synovial tissues with a specific perivascular distribution. CD271(+) SC density was increased in RA and OA compared with normal synovial tissues. T-cell proliferation and cytokine synthesis were similarly modified by CD271(+) and CD271(-) SCs. Sorted CD271(+) SCs from OA synovial tissues released significantly more interleukin (IL)-6, matrix metalloproteinase (MMP)-1, and MMP-3 than CD271(-) SCs. In immunodeficient mice, implants of CD271(+) SCs induced significantly higher myeloid cell infiltration than CD271(-) SCs. CONCLUSIONS: Our results demonstrate that CD271(+) perivascular SCs expand in RA and OA synovial tissues. CD271(+) cells showed enhanced proinflammatory properties ex vivo and in vivo, whereas immunoregulatory properties were equivalent in CD271(+) and CD271(-) SC.

Developmental, transcriptome, and genetic alterations associated with parthenocarpy in the grapevine seedless somatic variant Corinto bianco.

Seedlessness is a relevant trait in grapevine cultivars intended for fresh consumption or raisin production. Previous DNA marker analysis indicated that Corinto bianco (CB) is a parthenocarpic somatic variant of the seeded cultivar Pedro Ximenes (PX). This study compared both variant lines to determine the basis of this parthenocarpic phenotype. At maturity, CB seedless berries were 6-fold smaller than PX berries. The macrogametophyte was absent from CB ovules, and CB was also pollen sterile. Occasionally, one seed developed in 1.6% of CB berries. Microsatellite genotyping and flow cytometry analyses of seedlings generated from these seeds showed that most CB viable seeds were formed by fertilization of unreduced gametes generated by meiotic diplospory, a process that has not been described previously in grapevine. Microarray and RNA-sequencing analyses identified 1958 genes that were differentially expressed between CB and PX developing flowers. Genes downregulated in CB were enriched in gametophyte-preferentially expressed transcripts, indicating the absence of regular post-meiotic germline development in CB. RNA-sequencing was also used for genetic variant calling and 14 single-nucleotide polymorphisms distinguishing the CB and PX variant lines were detected. Among these, CB-specific polymorphisms were considered as candidate parthenocarpy-responsible mutations, including a putative deleterious substitution in a HAL2-like protein. Collectively, these results revealed that the absence of a mature macrogametophyte, probably due to meiosis arrest, coupled with a process of fertilization-independent fruit growth, caused parthenocarpy in CB. This study provides a number of grapevine parthenocarpy-responsible candidate genes and shows how genomic approaches can shed light on the genetic origin of woody crop somatic variants.

Clinicopathological correlations of podoplanin (gp38) expression in rheumatoid synovium and its potential contribution to fibroblast platelet crosstalk.

INTRODUCTION: Synovial fibroblasts (SF) undergo phenotypic changes in rheumatoid arthritis (RA) that contribute to inflammatory joint destruction. This study was undertaken to evaluate the clinical and functional significance of ectopic podoplanin (gp38) expression by RA SF. METHODS: Expression of gp38 and its CLEC2 receptor was analyzed by immunohistochemistry in synovial arthroscopic biopsies from RA patients and normal and osteoarthritic controls. Correlation between gp38 expression and RA clinicopathological variables was analyzed. In patients rebiopsied after anti-TNF-α therapy, changes in gp38 expression were determined. Platelet-SF coculture and gp38 silencing in SF were used to analyze the functional contribution of gp38 to SF migratory and invasive properties, and to SF platelet crosstalk. RESULTS: gp38 was abundantly but variably expressed in RA, and it was undetectable in normal synovial tissues. Among clinicopathologigal RA variables, significantly increased gp38 expression was only found in patients with lymphoid neogenesis (LN), and RF or ACPA autoantibodies. Cultured synovial but not dermal fibroblasts showed strong constitutive gp38 expression that was further induced by TNF-α. In RA patients, anti-TNF-α therapy significantly reduced synovial gp38 expression. In RA synovium, CLEC2 receptor expression was only observed in platelets. gp38 silencing in cultured SF did not modify their migratory and invasive properties but reduced the expression of IL-6 and IL-8 genes induced by SF-platelet interaction. CONCLUSIONS: In RA, synovial expression of gp38 is strongly associated to LN and it is reduced after anti-TNF-α therapy. Interaction between gp38 and CLEC2 platelet receptor is feasible in RA synovium in vivo and can specifically contribute to gene expression by SF.

Synovial fibroblast hyperplasia in rheumatoid arthritis: clinicopathologic correlations and partial reversal by anti-tumor necrosis factor therapy.

OBJECTIVE: Synovial fibroblast (SF) hyperplasia contributes to the pathogenesis of rheumatoid arthritis (RA), but quantitative information on this process is scarce. This study was undertaken to evaluate the fibroblast-specific marker Hsp47 as a quantitative marker for SFs and to analyze its clinicopathologic correlates and evolution after anti-tumor necrosis factor α (anti-TNFα) therapy. METHODS: Synovial biopsy samples were obtained from 48 patients with RA and 20 controls who were healthy or had osteoarthritis (OA). Twenty-five RA patients who had active disease at the time of biopsy underwent a second biopsy after anti-TNFα therapy. Immunolabeling for Hsp47, inflammatory cells, and vascular cell markers was performed. Hsp47-positive lining and sublining fractional areas were quantified, and their correlation with clinicopathologic variables was analyzed. RESULTS: In normal and diseased synovial tissue, Hsp47 was specifically and uniformly expressed by lining, sublining, and perivascular fibroblasts. Lining SF area was significantly increased in both RA and late OA tissue compared to normal tissue. Sublining SF area was increased in RA tissue but not in late OA tissue compared to normal tissue. Lining SF area was positively correlated with macrophage density, Disease Activity Score in 28 joints, and RA disease duration. In contrast, sublining SF area was negatively correlated with RA disease duration and activity. A significant reduction in lining SF area but not sublining SF area was observed after anti-TNFα therapy. CONCLUSION: Our findings indicate that Hsp47 is a reliable marker for quantifying SFs in human synovial tissue. Our data suggest that lining and sublining SFs undergo different dynamics during the course of the disease. Lining SF expansion parallels the activity and temporal progression of RA and can be partially reversed by anti-TNFα therapy.

CXCL12 gene expression is upregulated by hypoxia and growth arrest but not by inflammatory cytokines in rheumatoid synovial fibroblasts.

OBJECTIVES: CXCL12 is a constitutively expressed chemokine with important homeostatic functions. Increased CXCL12 expression has been observed in several inflammatory conditions, including rheumatoid arthritis (RA). This study was undertaken to identify potential mechanisms of regulation of CXCL12 gene expression by human fibroblasts under normal or inflammatory conditions. METHODS: Synovial fibroblasts (SF) were cultured from RA and osteoarthritis (OA) synovial tissues. CXCL12 mRNA expression was analysed by real time quantitative RT-PCR in RA-SF under different growth conditions, and exposed to hypoxia or to different pro-inflammatory factors. A 5'CXCL12 -1.4 kb promoter region fragment was cloned in a luciferase reporter plasmid and its activity analysed in human fibroblasts. RESULTS: CXCL12 mRNA expression was not constitutively increased in RA- compared to OA-SF. LPS, pro-inflammatory cytokines or growth factors did not induce CXCL12 mRNA expression in SF. Hypoxia and growth arrest by either serum starvation or confluent growth induced CXCL12 mRNA and protein expression in SF. Constitutive and induced expression of CXCL12 in fibroblasts was regulated at the transcriptional level by specific regions of the -1.4 kb promoter. CONCLUSIONS: Pro-inflammatory factors and cytokines do not up-regulate CXCL12 gene expression in SF. Growth arrest and hypoxia are potentially important inducers of CXCL12 expression in human fibroblasts and operate by regulating transcriptional activity of the promoter.

The transcriptional response of normal and rheumatoid arthritis synovial fibroblasts to hypoxia.

OBJECTIVE: Hypoxia is a prominent feature in rheumatoid arthritis (RA) synovium. However, its contribution to the pathogenesis of RA remains unclear. We undertook this study to systematically characterize the changes in gene expression induced by hypoxia in synovial fibroblasts. METHODS: We used microarray expression profiling in paired normoxic and hypoxic cultures of healthy synovial fibroblasts (HSFs) and RA synovial fibroblasts (RASFs). We used Student's paired t-test with Benjamini and Hochberg multiple testing correction to determine statistical significance. Validation of microarray data was performed by quantitative real-time reverse transcription-polymerase chain reaction analysis of selected genes. Biologic pathways differentially modulated by hypoxia in RASFs or HSFs were identified using unsupervised Ingenuity Pathways Analysis. RESULTS: Hypoxia induced significant changes in the expression of a large group of genes in both HSFs and RASFs. In RASFs, we observed a lower number of hypoxia-regulated genes and partial differences in their functional categories. The number of differentially expressed genes in RASFs compared with HSFs was significantly increased by hypoxia. Multiple gene sets involved in energy metabolism, intracellular signal transduction, angiogenesis, and immune and inflammatory pathways were significantly modified, the last in both proinflammatory and antiinflammatory directions. CONCLUSION: These data demonstrate that hypoxia induces significant changes in gene expression in HSFs and RASFs and identify differences between RASF and HSF profiles. The hypoxia-induced gene expression program in synovial fibroblasts identifies new factors and pathways relevant to understanding their contribution to the pathogenesis of chronic arthritis.

Surgical treatment of prosthetic valve endocarditis in patients with double prostheses: is single-valve replacement safe?

OBJECTIVE: Bias against operating on patients with prosthetic valve endocarditis (PVE) who have multiple prostheses may preclude the use of life-saving valve replacement. We investigated the accuracy of the preoperative diagnosis of PVE in patients with both mitral and aortic prosthesis and the safety of single-valve replacement when only one valve seemed infected. METHODS: Patients with a diagnosis of active PVE who had mitral and aortic prosthesis in place were assessed. We looked at the methods for diagnosis, causative agents, indication for valve replacement, operative findings and outcome. RESULTS: Twenty patients, who had both mitral and aortic prostheses and a diagnosis of PVE, were assessed. Streptococci and staphylococci caused 70% of cases. By means of echocardiography, the valves involved were: mitral (11 patients), aortic (six patients), and in three cases both prosthetic valves seemed infected. Surgery was undertaken in 17 patients (85%). The positive predictive value of transesophageal echocardiogram (TEE) for the preoperative diagnosis of the site of infection was 100%. In 13 patients, only the prosthetic valve that seemed infected was replaced. Four of these patients died within a week after the procedure. Nine patients survived the surgical procedure, completed a course of antimicrobial therapy and were followed up for 15.78 months (95% CI: 12.83-18.72). All were considered cured and relapses were not observed. CONCLUSIONS: TEE allowed a diagnosis of site involvement that did correlate with the anatomic diagnosis obtained during the operation. This fact contributed to the management of patients and was of great help in guiding the surgical intervention. Echo-oriented single-valve replacement may be a safe strategy for patients with PVE and double prostheses.

Immature blood vessels in rheumatoid synovium are selectively depleted in response to anti-TNF therapy.

BACKGROUND: Angiogenesis is considered an important factor in the pathogenesis of Rheumatoid Arthritis (RA) where it has been proposed as a therapeutic target. In other settings, active angiogenesis is characterized by pathologic, immature vessels that lack periendothelial cells. We searched for the presence of immature vessels in RA synovium and analyzed the dynamics of synovial vasculature along the course of the disease, particularly after therapeutic response to TNF antagonists. METHODOLOGY/PRINCIPAL FINDINGS: Synovial arthroscopic biopsies from RA, osteoarthritis (OA) and normal controls were analyzed by double labeling of endothelium and pericytes/smooth muscle mural cells to identify and quantify mature/immature blood vessels. To analyze clinicopathological correlations, a cross-sectional study on 82 synovial biopsies from RA patients with variable disease duration and severity was performed. A longitudinal analysis was performed in 25 patients with active disease rebiopsied after anti-TNF-alpha therapy. We found that most RA synovial tissues contained a significant fraction of immature blood vessels lacking periendothelial coverage, whereas they were rare in OA, and inexistent in normal synovial tissues. Immature vessels were observed from the earliest phases of the disease but their presence or density was significantly increased in patients with longer disease duration, higher activity and severity, and stronger inflammatory cell infiltration. In patients that responded to anti-TNF-alpha therapy, immature vessels were selectively depleted. The mature vasculature was similarly expanded in early or late disease and unchanged by therapy. CONCLUSION/SIGNIFICANCE: RA synovium contains a significant fraction of neoangiogenic, immature blood vessels. Progression of the disease increases the presence and density of immature but not mature vessels and only immature vessels are depleted in response to anti-TNFalpha therapy. The different dynamics of the mature and immature vascular fractions has important implications for the development of anti-angiogenic interventions in RA.

[Amyloid goiter secondary to Crohn's disease]. / Bocio amiloide secundario a enfermedad de Crohn.

Secondary amyloidosis is generally caused by malignant tumors or chronic inflammatory diseases. Most cases of secondary amyloidosis are discovered due to proteinuria or nephrotic syndrome caused by renal amyloidosis. Clinically significant thyroid involvement is found in only a small percentage of cases, although a finding of amyloid deposit in autopsies is not infrequent. We present a case of amyloid goiter. The patient was diagnosed with Crohn's disease 7 years previously and had kidney failure of unknown cause. She was referred to our department for a goiter discovered incidentally. The patient finally underwent thyroidectomy due to progressive growth of the thyroid gland with compressive symptoms. The histologic analysis showed thyroid amyloidosis.

Human inflammatory synovial fibroblasts induce enhanced myeloid cell recruitment and angiogenesis through a hypoxia-inducible transcription factor 1alpha/vascular endothelial growth factor-mediated pathway in immunodeficient mice.

OBJECTIVE: Hyperplasia and phenotypic changes in fibroblasts are often observed in chronic inflammatory lesions, and yet the autonomous pathogenic contribution of these changes is uncertain. The purpose of this study was to analyze the intrinsic ability of fibroblasts from chronically inflamed synovial tissue to drive cell recruitment and angiogenesis. METHODS: Fibroblasts from patients with rheumatoid arthritis (RA) or osteoarthritis (OA), as well as fibroblasts from healthy synovial tissue and healthy skin, were cultured and subcutaneously engrafted into immunodeficient mice. Cell infiltration and angiogenesis were analyzed in the grafts by immunohistochemical studies. The role of vascular endothelial growth factor (VEGF), CXCL12, and hypoxia-inducible transcription factor 1alpha (HIF-1alpha) in these processes was investigated using specific antagonists or small interfering RNA (siRNA)-mediated down-regulation of HIF-1alpha in fibroblasts. RESULTS: Inflammatory (OA and RA) synovial fibroblasts, compared with healthy dermal or synovial tissue fibroblasts, induced a significant enhancement in myeloid cell infiltration and angiogenesis in immunodeficient mice. These activities were associated with increased constitutive and hypoxia-induced expression of VEGF, but not CXCL12, in inflammatory fibroblasts compared with healthy fibroblasts. VEGF and CXCL12 antagonists significantly reduced myeloid cell infiltration and angiogenesis. Furthermore, targeting of HIF-1alpha expression by siRNA or of HIF-1alpha transcriptional activity by the small molecule chetomin in RA fibroblasts significantly reduced both responses. CONCLUSION: These results demonstrate that chronic synovial inflammation is associated with stable fibroblast changes that, under hypoxic conditions, are sufficient to induce inflammatory cell recruitment and angiogenesis, both of which are processes relevant to the perpetuation of chronic inflammation.

Cell cycle regulation by FasL and Apo2L/TRAIL in human T-cell blasts. Implications for autoimmune lymphoproliferative syndromes.

The Fas-FasL pathway plays an important role in the homeostasis of mature lymphocytes, with defects causing autoimmune lymphoproliferative syndromes (ALPS). Human T-cell blasts are not sensitive to FasL or Apo2L/TRAIL-induced apoptosis unless they get reactivated, but either of those ligands inhibits their growth in the absence of cell death induction due to a cell cycle arrest in S-G2/M. In the present work, we have studied the mechanism(s) by which FasL or Apo2L/TRAIL regulate T-cell blast cell cycle in healthy donors and in two types of ALPS patients. Our data indicate that in human CD8+ T-cell blasts, Fas ligation, and especially Apo2L/TRAIL induce the p53-dependent decrease in cyclin-B1 levels. However, the induction of the negative cell cycle regulator p21WAF1 by FasL or Apo2L/TRAIL in either CD4+ or CD8+ T-cell blasts seems to be the main regulatory mechanism. This mechanism is dependent on caspase activation and on H2O2 generation. The increase in p21 levels by FasL or Apo2L/TRAIL is concomitant with p53 increases only in CD8+ T-cell blasts, with p21 levels maintained high for longer times than p53 levels. In CD4+ T-cell blasts p21 levels are controlled through a transient and p53-independent mechanism. The present results suggest that the etiology of ALP syndromes could be related not only to defects in apoptosis induction, but also in cell cycle regulation.

Multicystic/cavitated giant left atrial myxomas: a matter of technology?

We present the case of a rare echocardiographic image of a giant cavitated myxoma and the pathologic findings of the cystic mass. The new echocardiographic equipment not only has improved the sensitivity for diagnosis of different pathologies but also has redefined its visual and morphologic characteristics. Although most myxomas are solid masses and some cystic myxomas have been reported, the presence of multiple cavities on echocardiographic exam has exceptionally been described. While cystic changes have been described at autopsy in 14% of cardiac myxomas, its identification with echocardiography is rare. Nowadays, the new echocardiographic equipment has improved the quality and the accuracy to detect and describe intracardiac masses, showing myxomas with cystic cavities in vivo that in the past was a pathologic finding.

Thyrotoxicosis and low iodine uptake in a woman with graves' disease.

Thyrotoxicosis factitia is defined as thyrotoxicosis resulting from exogenous ingestion of thyroid hormone, usually in patients with a psychiatric disorder. Diagnosis can be difficult and this entity should be suspected in patients with high free tiroxine (T4) concentrations, low or suppressed thyroglobulin concentrations, normal urinary iodide excretion and low or suppressed (131)I uptake. To establish the differential diagnosis, thyrotoxicosis factitia must be distinguished from several diseases with low (131)I uptake, such as Graves' disease, subacute thyroiditis, hyperthyroidism due to excessive iodine intake, struma ovarii and metastasis from thyroid cancer. Treatment is based on b-blockers to reduce symptoms and avoid iatrogeny. We present a case of thyrotoxicosis factitia treated in our outpatient clinic.

Microscopic and transcriptome analyses of early colonization of tomato roots by Trichoderma harzianum.

The capacity of the fungus Trichoderma harzianum CECT 2413 to colonize roots and stimulate plant growth was analyzed. Tobacco seedlings (Nicotiana benthamiana) transferred to Petri dishes inoculated with T. harzianum conidia showed increased plant fresh weight (140%) and foliar area (300%), as well as the proliferation of secondary roots (300%) and true leaves (140%). The interaction between strain CECT 2413 and the tomato-root system was also studied during the early stages of root colonization by the fungus. When T. harzianum conidia were inoculated into the liquid medium of hydroponically grown tomato plants (Lycopersicum esculentum), profuse adhesion of hyphae to the plant roots as well as colonization of the root epidermis and cortex were observed. Confocal microscopy of a T. harzianum transformant that expressed the green fluorescent protein (GFP) revealed intercellular hyphal growth and the formation of plant-induced papilla-like hyphal tips. Analysis of the T. harzianum-tomato interaction in soil indicated that the contact between T. harzianum and the roots persisted over a long period of time. This interaction was characterized by the presence of yeast-like cells, a novel and previously undescribed developmental change. To study the molecular mechanism underlying fungal ability to colonize the tomato-root system, the T. harzianum transcriptome was analyzed during the early stages of the plant-fungus interaction. The expression of fungal genes related to redox reactions, lipid metabolism, detoxification, and sugar or amino-acid transport increased when T. harzianum colonized tomato roots. These observations are similar to those regarding the interactions of mycorrhiza and pathogenic fungi with plants.

Autoimmune lymphoproliferative syndrome (ALPS) in a patient with a new germline Fas gene mutation.

Autoimmune lymphoproliferative syndrome (ALPS) is a rare genetic disorder characterized by chronic lymphoproliferation, autoimmune manifestations and expansion of TCRalphabeta+CD4-CD8- lymphocytes. The main pathogenic factor is a defective Fas-mediated apoptosis generally caused by mutations in the Fas gene. This report describes a new heterozygous Fas gene mutation in a boy with clinical and immunological features of ALPS. In vitro, T-cell blasts from the patient are completely resistant to the effects on the anti-Fas cytotoxic mAb CH-11, they also have a higher proliferation rate than T cells from healthy donors, while PHA-induced AICD is normal. The location of the mutation (I246S) found in the intracytoplasmic death domain, and the conservation of that residue in four different species from human suggest that I246 is an essential amino acid for Fas function. The patient has inherited the mutation from his father who also shows defective Fas-mediated apoptosis but the clinical and immunological manifestations are much less severe. These results provide evidence that the penetrance of genetic defects in Fas is variable and that other factors may influence the phenotype of the disease.

A homozygous Fas ligand gene mutation in a patient causes a new type of autoimmune lymphoproliferative syndrome.

Autoimmune lymphoproliferative syndrome (ALPS) is characterized by lymphoproliferation and autoimmune clinical manifestations and is generally caused by defective Fas-mediated apoptosis. This report describes the first homozygous FASL gene mutation in a woman with clinical and immunologic features of ALPS. T-cell blasts from the patient did not induce FasL-mediated apoptosis on Fas-transfected murine L1210 or on Jurkat cells, and activation-induced cell death was impaired. Furthermore, Fas-dependent cytotoxicity was drastically reduced in COS cells transfected with the mutant FasL. In addition, FasL expression on T-cell blasts from the patient was similar to that observed in a healthy control, despite its bearing the high-producer genotype -844C/C in the FASL promoter. Sequencing of the patient's FASL gene revealed a new mutation in exon 4 (A247E). The location of A247E in the FasL extracellular domain and the conservation of the protein sequence of that region recorded in 8 species different from humans support the essential role of FasL COOH terminal domain in Fas/FasL binding. These findings provide evidence that inherited nonlethal FASL abnormalities cause an uncommon apoptosis defect producing lymphoproliferative disease, and they highlight the need for a review of the current ALPS classification to include a new ALPS type Ic subgroup.