The knowledge of hereditary predisposition has changed our understanding of Pulmonary Arterial Hypertension. Genetic testing has been widely extended and the application of Pulmonary Arterial ...Hypertension specific gene panels has allowed its inclusion in the diagnostic workup and increase the diagnostic ratio compared to the traditional sequencing techniques. This is particularly important in the differential diagnosis between Pulmonary Arterial Hypertension and Pulmonary Venoocclusive Disease.
Since November 2011, genetic testing is offered to all patients with idiopathic, hereditable and associated forms of Pulmonary Arterial Hypertension or Pulmonary Venoocclusive Disease included in the Spanish Registry of Pulmonary Arterial Hypertension. Herein, we present the clinical phenotype and prognosis of all Pulmonary Arterial Hypertension patients with disease-associated variants in TBX4.
Out of 579 adults and 45 children, we found in eight patients from seven families, disease-causing associated variants in TBX4. All adult patients had a moderate-severe reduction in diffusion capacity. However, we observed a wide spectrum of clinical presentations, including Pulmonary Venoocclusive Disease suspicion, interstitial lung disease, pulmonary vascular abnormalities and congenital heart disease.
Genetic testing is now essential for a correct diagnosis work-up in Pulmonary Arterial Hypertension. TBX4-associated Pulmonary Arterial Hypertension has marked clinical heterogeneity. In this regard, a genetic study is extremely useful to obtain an accurate diagnosis and provide appropriate management.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Enterotoxigenic
(ETEC) strains produce at least one of two types of enterotoxins: the heat-labile (LT) and heat-stable (ST) toxins, which are responsible for the watery secretory diarrhoea that is a ...hallmark of the human ETEC infection. One regulatory system that controls the transcription of virulence genes in pathogenic bacteria is the CpxRA two-component system (TCS). We reported that the
bicistronic operon, which encodes for the A and B subunits of LT, was repressed for the CpxRA TCS by direct binding of CpxR-P from -12 to +6 bp with respect to the transcription start site of
. Moreover, the Cpx-response activation down-regulated the transcription of
genes, and this negative effect was CpxRA-dependent. Our data show that CpxRA TCS is a negative regulator of the LT, one of the main virulence determinants of ETEC.
Different methodological approaches are available to assess DNA methylation biomarkers. In this study, we evaluated two sodium bisulfite conversion-dependent methods, namely pyrosequencing and ...methylation-specific qPCR (MS-qPCR), with the aim of measuring the closeness of agreement of methylation values between these two methods and its effect when setting a cut-off. Methylation of tumor suppressor gene
was evaluated in 80 lung cancer patients from which cytological lymph node samples were obtained. Cluster analyses were used to establish methylated and unmethylated groups for each method. Agreement and concordance between pyrosequencing and MS-qPCR was evaluated with Pearson's correlation, Bland-Altman, Cohen's kappa index and ROC curve analyses. Based on these analyses, cut-offs were derived for MS-qPCR. An acceptable correlation (Pearson's R2 = 0.738) was found between pyrosequencing (PYRmean) and MS-qPCR (NMP; normalized methylation percentage), providing similar clinical results when categorizing data as binary using cluster analysis. Compared to pyrosequencing, MS-qPCR tended to underestimate methylation for values between 0 and 15%, while for methylation >30% overestimation was observed. The estimated cut-off for MS-qPCR data based on cluster analysis, kappa-index agreement and ROC curve analysis were much lower than that derived from pyrosequencing. In conclusion, our results indicate that independently of the approach used for estimating the cut-off, the methylation percentage obtained through MS-qPCR is lower than that calculated for pyrosequencing. These differences in data and therefore in the cut-off should be examined when using methylation biomarkers in the clinical practice.
is a resident of the human gut. However, certain
toxigenic strains exist that secrete the nonribosomal peptide tilivalline (TV) cytotoxin. TV is a pyrrolobenzodiazepine that causes ...antibiotic-associated hemorrhagic colitis (AAHC). The biosynthesis of TV is driven by enzymes encoded by the
and NRPS operons. In this study, we determined the effect of environmental signals such as carbon sources, osmolarity, and divalent cations on the transcription of both TV biosynthetic operons. Gene expression was enhanced when bacteria were cultivated in tryptone lactose broth. Glucose, high osmolarity, and depletion of calcium and magnesium diminished gene expression, whereas glycerol increased transcription of both TV biosynthetic operons. The cAMP receptor protein (CRP) is a major transcriptional regulator in bacteria that plays a key role in metabolic regulation. To investigate the role of CRP on the cytotoxicity of
, we compared levels of expression of TV biosynthetic operons and synthesis of TV in wild-type strain MIT 09-7231 and a Δ
isogenic mutant. In summary, we found that CRP directly activates the transcription of the
and NRPS operons and that the absence of CRP reduced cytotoxicity of
on HeLa cells, due to a significant reduction in TV production. This study highlights the importance of the CRP protein in the regulation of virulence genes in enteric bacteria and broadens our knowledge on the regulatory mechanisms of the TV cytotoxin.
Background:
ALMS1
is a ubiquitous gene associated with Alström syndrome (ALMS). The main symptoms of ALMS affect multiple organs and tissues, generating at last, multi-organic fibrosis in the lungs, ...kidneys and liver. TGF-β is one of the main pathways implicated in fibrosis, controlling the cell cycle, apoptosis, cell migration, cell adhesion and epithelial-mesenchymal transition (EMT). Nevertheless, the role of
ALMS1
gene in fibrosis generation and other implicated processes such as cell migration or cell adhesion
via
the TGF- β pathway has not been elucidated yet.
Methods:
Initially, we evaluated how depletion of
ALMS1
affects different processes like apoptosis, cell cycle and mitochondrial activity in HeLa cells. Then, we performed proteomic profiling with TGF-β stimuli in HeLa
ALMS1
−/− cells and validated the results by examining different EMT biomarkers using qPCR. The expression of these EMT biomarkers were also studied in hTERT-BJ-5ta
ALMS1
−/−. Finally, we evaluated the SMAD3 and SMAD2 phosphorylation and cell migration capacity in both models.
Results:
Depletion of
ALMS1
generated apoptosis resistance to thapsigargin (THAP) and C2-Ceramide (C2-C), and G2/M cell cycle arrest in HeLa cells. For mitochondrial activity, results did not show significant differences between
ALMS1 +/+
and
ALMS1 −/−
. Proteomic results showed inhibition of downstream pathways regulated by TGF-β. The protein-coding genes (PCG) were associated with processes like focal adhesion or cell-substrate adherens junction in HeLa.
SNAI1
showed an opposite pattern to what would be expected when activating the EMT in HeLa and BJ-5ta. Finally, in BJ-5ta model a reduced activation of SMAD3 but not SMAD2 were also observed. In HeLa model no alterations in the canonical TGF-β pathway were observed but both cell lines showed a reduction in migration capacity.
Conclusion:
ALMS1
has a role in controlling the cell cycle and the apoptosis processes. Moreover, the depletion of
ALMS1
affects the signal transduction through the TGF-β and other processes like the cell migration and adhesion capacity.
Three to four months after hospitalisation for COVID-19 pneumonia, the most frequently described alteration in respiratory function tests (RFTs) is decreased carbon monoxide transfer capacity (DL
).
...This is a prospective cohort study that included patients hospitalised because of SARS-CoV-2 pneumonia, three months after their discharge. A clinical evaluation, analytical parameters, chest X-ray, six-minute walk test, spirometry and DL
-DL
analysis were performed. Demographic variables, comorbidities, and variables related to the severity of the admission were recorded.
Two hundred patients completed the study; 59.5% men, age 62 years, 15.5% admitted to the intensive care unit. The most frequent functional alteration, in 27% of patients, was in the DL
-DL
combination. This alteration was associated with age, male sex, degree of dyspnoea, poorer perception of health, and limited ability for physical effort. These patients also presented higher levels of D-Dimer and more residual radiological alterations. In 42% of the patients with diffusion alterations, only reduced DL
was presented, along with lower D-Dimer levels and less capillary volume involvement. The severity of the process was associated with the reduction in DL
-DL
.
The most sensitive RFT for the detection of the sequelae of COVID-19 pneumonia was the combined measurement of DL
-DL
and this factor was related to patient health status and their capacity for physical exertion. In 40% of these cases, there was only a reduction in DL
, a finding that may indicate less pulmonary vascular involvement.
Enterotoxigenic
produces a myriad of adhesive structures collectively named colonization factors (CFs). CS3 is a CF, which is assembled into fine wiry fibrillae encoded by the
gene cluster. In this ...work we evaluated the influence of environmental cues such as temperature, osmolarity, pH, and carbon source on the expression of CS3 genes. The transcription of
major pilin gene was stimulated by growth of the bacteria in colonization factor broth at 37°C; the presence of glycerol enhanced
transcription, while glucose at high concentration, high osmolarity, and the depletion of divalent cations such as calcium and magnesium repressed
expression. In addition, we studied the role of H-NS, CpxRA, and CRP global regulators in CS3 gene expression. H-NS and CpxRA acted as repressors and CRP as an activator of
expression. Under high osmolarity, H-NS, and CpxRA were required for
repression. CS3 was required for both, bacterial adherence to epithelial cells and biofilm formation. Our data strengthens the existence of a multi-factorial regulatory network that controls transcription of CS3 genes in which global regulators, under the influence of environmental signals, control the production of this important intestinal colonization factor.
The acquisition of Salmonella pathogenicity island 2 (SPI-2) conferred on Salmonella the ability to survive and replicate within host cells. The
bicistronic operon, located in SPI-2, encodes the ...SsrAB two-component system (TCS), which is the central positive regulator that induces the expression of SPI-2 genes as well as other genes located outside this island. On the other hand, CpxRA is a two-component system that regulates expression of virulence genes in many bacteria in response to different stimuli that perturb the cell envelope. We previously reported that the CpxRA system represses the expression of SPI-1 and SPI-2 genes under SPI-1-inducing conditions by decreasing the stability of the SPI-1 regulator HilD. Here, we show that under SPI-2-inducing conditions, which mimic the intracellular environment, CpxRA represses the expression of SPI-2 genes by the direct action of phosphorylated CpxR (CpxR-P) on the
regulatory operon. CpxR-P recognized two sites located proximal and distal from the promoter located upstream of
. Consistently, we found that CpxRA reduces the replication of Salmonella enterica serovar Typhimurium inside murine macrophages. Therefore, our results reveal CpxRA as an additional regulator involved in the intracellular lifestyle of Salmonella, which in turn adds a new layer to the intricate regulatory network controlling the expression of Salmonella virulence genes.
SPI-2 encodes a type III secretion system (T3SS) that is a hallmark for the species Salmonella enterica, which is essential for the survival and replication within macrophages. Expression of SPI-2 genes is positively controlled by the two-component system SsrAB. Here, we determined a regulatory mechanism involved in controlling the overgrowth of Salmonella inside macrophages. In this mechanism, CpxRA, a two-component system that is activated by extracytoplasmic stress, directly represses expression of the
regulatory operon; as a consequence, expression of SsrAB target genes is decreased. Our findings reveal a novel mechanism involved in the intracellular lifestyle of Salmonella, which is expected to sense perturbations in the bacterial envelope that Salmonella faces inside host cells, as the synthesis of the T3SS-2 itself.
successfully colonizes host tissues by recognizing and interacting with cholesterol present on membrane-associated lipid rafts. In this study, we evaluated the role of cholesterol in the expression ...of capsule polysaccharide genes of
and its implication in resistance to phagocytosis. Our data revealed that exogenous cholesterol added to
increases macrophage-mediated phagocytosis. To explain this event, the expression of capsular
, and
genes was determined in the presence of cholesterol. Down-regulation of these capsular genes occurred leading to increased susceptibility to phagocytosis by macrophages. In contrast, depletion of cholesterol from macrophage membranes led to enhanced expression of
, and
genes and to capsule production resulting in resistance to macrophage-mediated phagocytosis. Cholesterol-mediated repression of capsular genes was dependent on the RcsA and H-NS global regulators. Finally, cholesterol also down-regulated the expression of genes responsible for LPS core oligosaccharides production and OMPs. Our results suggest that cholesterol plays an important role for the host by reducing the anti-phagocytic properties of the
capsule facilitating bacterial engulfment by macrophages during the bacteria-eukaryotic cell interaction mediated by lipid rafts.
Pulmonary arterial hypertension (PAH) is an infrequent disorder characterized by high blood pressure in the pulmonary arteries. It may lead to premature death or the requirement for lung and/or heart ...transplantation. Genetics plays an important and increasing role in the diagnosis of PAH. Here, we report seven additional patients with variants in
and a review of sixty previously described patients in the literature. Patients described in this study suffered with additional conditions including large septal defects, as described by other groups. Collectively, sixty-seven PAH patients have been reported so far with variants in
, including missense and loss-of-function (LoF) variants. The majority of the loss-of-function variants found in
were detected in the last exon of the gene. Meanwhile, most missense variants were located within exon one, suggesting a probable tolerated change at the amino terminal part of the protein. In addition, we reported two idiopathic PAH patients presenting with the same variant previously detected in five patients by other studies, suggesting a possible hot spot. Research conducted on PAH associated with congenital heart disease (CHD) indicated that variants in
might be particularly prevalent in this subgroup, as two out of our seven additional patients presented with CHD. Further research is still necessary to clarify the precise association between the biological pathway of
and the development of PAH.
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