In Vitro Evaluation of Non-Protein Adsorbing Breast Cancer Theranostics Based on 19F-Polymer Containing Nanoparticles

Eight fluorinated nanoparticles (NPs) are synthesized, loaded with doxorubicin (DOX), and evaluated as theranostic delivery platforms to breast cancer cells. The multifunctional NPs are formed by self-assembly of either linear or star-shaped amphiphilic block copolymers, with fluorinated segments incorporated in the hydrophilic corona of the carrier. The sizes of the NPs confirm that small circular NPs are formed. The release kinetics data of the particles reveals clear hydrophobic core dependence, with longer sustained release from particles with larger hydrophobic cores, suggesting that the DOX release from these carriers can be tailored. Viability assays and flow cytometry evaluation of the ratios of apoptosis/necrosis indicate that the materials are non-toxic to breast cancer cells before DOX loading; however, they are very efficient, similar to free DOX, at killing cancer cells after drug encapsulation. Both flow cytometry and confocal microscopy confirm the cellular uptake of NPs and DOX-NPs into breast cancer cells, and in vitro 19F-MRI measurement shows that the fluorinated NPs have strong imaging signals, qualifying them as a potential in vivo contrast agent for 19F-MRI

Sacral agenesis: a pilot whole exome sequencing and copy number study

Background: Caudal regression syndrome (CRS) or sacral agenesis is a rare congenital disorder characterized by a constellation of congenital caudal anomalies affecting the caudal spine and spinal cord, the hindgut, the urogenital system, and the lower limbs. CRS is a complex condition, attributed to an abnormal development of the caudal mesoderm, likely caused by the effect of interacting genetic and environmental factors. A well-known risk factor is maternal type 1 diabetes. Method: Whole exome sequencing and copy number variation (CNV) analyses were conducted on 4 Caucasian trios to identify de novo and inherited rare mutations. Results: In this pilot study, exome sequencing and copy number variation (CNV) analyses implicate a number of candidate genes, including SPTBN5, MORN1, ZNF330, CLTCL1 and PDZD2. De novo mutations were found in SPTBN5, MORN1 and ZNF330 and inherited predicted damaging mutations in PDZD2 (homozygous) and CLTCL1 (compound heterozygous). Importantly, predicted damaging mutations in PTEN (heterozygous), in its direct regulator GLTSCR2 (compound heterozygous) and in VANGL1 (heterozygous) were identified. These genes had previously been linked with the CRS phenotype. Two CNV deletions, one de novo (chr3q13.13) and one homozygous (chr8p23.2), were detected in one of our CRS patients. These deletions overlapped with CNVs previously reported in patients with similar phenotype. Conclusion: Despite the genetic diversity and the complexity of the phenotype, this pilot study identified genetic features common across CRS patients

Doença de Fabry : diagnóstico de uma doença rara

Fabry disease (FD) is an X-linked inborn error of glycosphingolipid metabolism due to the deficiency of α-galactosidase A. The progressive accumulation of globotriaosylceramide (Gb3), particularly in the vascular endothelium, leads to renal, cardiac, and cerebrovascular manifestations and early death. Clinical manifestations include the onset of pain and paresthesias in extremities, angiokeratoma and hypohidrosis during childhood or adolescence. Proteinuria and lymphedema occur with increasing age. Severe renal impairment leads to hypertension and uremia. Death usually occurs due to renal failure or cardiac or cerebrovascular disease. Disease presentation may be subtle, and its signs and symptoms are often discounted as malingering or are mistakenly attributed to other disorders, such as rheumatic fever, neurosis, multiple sclerosis, lupus, or petechiae. We present a 46-year-old man who since adolescence has suffered from painful acroparesthesia, disseminated skin angiokeratomas, hypohidrosis and heat intolerance. He was submitted to a thorough investigation with different specialists, but never reached a diagnosis. He started hemodialysis 3 years ago and at the moment is in standby for kidney transplantation. He was enrolled in a Brazilian FD screening and a reduced serum activity of α-galactosidase A (0.0027 nmol/h/mL – reference value 4-22) confirmed the diagnosis of FD He has angiokeratoma at the bottom area, his echocardiogram demonstrated left ventricular hypertrophy and the family history is very rich, as the patient has 15 siblings. This case represents a very common story for FD patients. They usually spend most of their lives trying to find someone who could understand or explain their suffering. These results indicate that FD may be much more common among male dialysis patients than previously recognized. Subsequently, FD should be considered in every patient with unexplained renal disease, especially when cardiac or cerebral complications suggest an underlying multisystemic disorder. Early diagnosis of FD is important because it allows family studies to identify other affected relatives for genetic counseling and therapeutic intervention.A doença de Fabry (DF) é um erro inato do metabolismo dos glicoesfingolipídeos devido à deficiência da α-galactosidase A. O acúmulo progressivo de globotriaosilceramida (Gb3),particularmente no endotélio vascular, leva a manifestações renais, cardíacas e cerebrovasculares e morte precoce. As manifestações clínicas incluem o início, durante a infância ou adolescência, de episódios de dor e parestesias nas extremidades, angioqueratomas e hipohidrose. Com a idade, podem aparecer proteinúria e linfedema. Insuficiência renal grave leva à hipertensão e uremia. O óbito ocorre devido à insuficiência renal ou doença cardíaca ou cerebrovascular. A apresentação da doença pode ser sutil, e seus sinais e sintomas são erroneamente atribuídos a outras doenças, como febre reumática, neurose, esclerose múltipla, lúpus ou petéquias. Relatamos o caso de um paciente masculino com 46 anos que, desde a adolescência, sofre de acroparestesia, angioqueratomas disseminados, hipohidrose e intolerância ao calor. Ele foi submetido a extensa investigação com diferentes especialistas, mas nunca chegou a um diagnóstico. Iniciou hemodiálise há 3 anos e, no momento, está na lista de espera para transplante de rim. Participou de um programa brasileiro de triagem para DF, e uma atividade reduzida de α- galactosidase A (0,0027 nmol/h/mL – valor de referência 4-22) confirmou o diagnóstico de DF. O paciente apresenta angioqueratomas na área do calção, seu ecocardiograma demonstra hipertrofia ventricular esquerda e sua história familiar é rica, pois ele tem 15 irmãos. Este caso representa uma história muito comum entre pacientes com DF. Eles geralmente passam a maior parte de suas vidas tentando encontrar alguém que compreenda ou explique seu sofrimento. Estes resultados indicam que a DF pode ser muito mais comum entre homens que realizam hemodiálise do que antes previsto. Subseqüentemente, a DF deve ser considerada em todo paciente com doença renal sem causa aparente, principalmente quando complicações cardíacas ou cerebrovasculares sugerirem uma doença multissistêmica. O diagnóstico precoce da DF é importante, pois permite estudo familiar para identificar parentes afetados para aconselhamento genético e intervenção terapêutica

Calcium Binding Properties of the Kingella kingae PilC1 and PilC2 Proteins Have Differential Effects on Type IV Pilus-Mediated Adherence and Twitching Motility

Kingella kingae is an emerging bacterial pathogen that is being recognized increasingly as an important etiology of septic arthritis, osteomyelitis, and bacteremia, especially in young children. The pathogenesis of K. kingae disease begins with bacterial adherence to respiratory epithelium, which is dependent on type IV pili and is influenced by two PilC-like proteins called PilC1 and PilC2. Production of either PilC1 or PilC2 is necessary for K. kingae piliation and bacterial adherence. In this study, we set out to further investigate the role of PilC1 and PilC2 in type IV pilus-associated phenotypes. We found that PilC1 contains a functional 9-amino-acid calcium-binding (Ca-binding) site with homology to the Pseudomonas aeruginosa PilY1 Ca-binding site and that PilC2 contains a functional 12-amino-acid Ca-binding site with homology to the human calmodulin Ca-binding site. Using targeted mutagenesis to disrupt the Ca-binding sites, we demonstrated that the PilC1 and PilC2 Ca-binding sites are dispensable for piliation. Interestingly, we showed that the PilC1 site is necessary for twitching motility and adherence to Chang epithelial cells, while the PilC2 site has only a minor influence on twitching motility and no influence on adherence. These findings establish key differences in PilC1 and PilC2 function in K. kingae and provide insights into the biology of the PilC-like family of proteins

Fabry disease: recent advances in pathology, diagnosis, treatment and monitoring

<p>Abstract</p> <p>Background</p> <p>In Fabry disease (α-galactosidase A deficiency) accumulation of Globotriaosylceramide (Gb3) leads to progressive organ failure and premature death. The introduction of enzyme replacement therapy (ERT) was the beginning of a new era in this disorder, and has prompted a broad range of research activities. This review aims to summarize recent developments and progress with high impact for Fabry disease.</p> <p>Methods</p> <p>A Pubmed analysis was performed using the search terms "Fabry disease", "Anderson-Fabry disease", "alpha-galactosidase A" and "Gb3". Of the given publications by 31st January 2009 only original articles recently published in peer reviewed journals were included for this review. Case reports were included only when they comprised a new aspect. In addition we included relevant conference abstracts when the results had not already been published as original articles.</p> <p>Results</p> <p>Apart from Gb3-accumulation cellular and organ specific damages may be related also to inflammatory and immunological consequences. It will be interesting whether this may lead to new therapeutic strategies in the treatment of Fabry disease. Since newborn screening is still difficult in Fabry disease, detection of patients in populations at risk is of great importance. Undiagnosed patients with Fabry disease may still be found in cohorts of subjects with renal diseases, cardiomyopathy and TIA or stroke. Efforts should be undertaken to identify these individuals and initialise ERT in order to hault disease progression. It has also been demonstrated that Gb3-accumulation leads to pre-clinical damages and it is believed that early treatment may be the only possibility so far to prevent irreversible organ damage.</p

Znf202 Affects High Density Lipoprotein Cholesterol Levels and Promotes Hepatosteatosis in Hyperlipidemic Mice

Background: The zinc finger protein Znf202 is a transcriptional suppressor of lipid related genes and has been linked to hypoalphalipoproteinemia. A functional role of Znf202 in lipid metabolism in vivo still remains to be established. Methodology and Principal Findings: We generated mouse Znf202 expression vectors, the functionality of which was established in several in vitro systems. Next, effects of adenoviral znf202 overexpression in vivo were determined in normo- as well as hyperlipidemic mouse models. Znf202 overexpression in mouse hepatoma cells mhAT3F2 resulted in downregulation of members of the Apoe/c1/c2 and Apoa1/c3/a4 gene cluster. The repressive activity of Znf202 was firmly confirmed in an apoE reporter assay and Znf202 responsive elements within the ApoE promoter were identified. Adenoviral Znf202 transfer to Ldlr-/- mice resulted in downregulation of apoe, apoc1, apoa1, and apoc3 within 24 h after gene transfer. Interestingly, key genes in bile flux (abcg5/8 and bsep) and in bile acid synthesis (cyp7a1) were also downregulated. At 5 days post-infection, the expression of the aforementioned genes was normalized, but mice had developed severe hepatosteatosis accompanied by hypercholesterolemia and hypoalphalipoproteinemia. A much milder phenotype was observed in wildtype mice after 5 days of hepatic Znf202 overexpression. Interestingly and similar to Ldl-/- mice, HDL-cholesterol levels in wildtype mice were lowered after hepatic Znf202 overexpression. Conclusion/Significance: Znf202 overexpression in vivo reveals an important role of this transcriptional regulator in liver lipid homeostasis, while firmly establishing the proposed key role in the control of HDL levels

A Machine Learning Approach for Identifying Novel Cell Type–Specific Transcriptional Regulators of Myogenesis

Transcriptional enhancers integrate the contributions of multiple classes of transcription factors (TFs) to orchestrate the myriad spatio-temporal gene expression programs that occur during development. A molecular understanding of enhancers with similar activities requires the identification of both their unique and their shared sequence features. To address this problem, we combined phylogenetic profiling with a DNA–based enhancer sequence classifier that analyzes the TF binding sites (TFBSs) governing the transcription of a co-expressed gene set. We first assembled a small number of enhancers that are active in Drosophila melanogaster muscle founder cells (FCs) and other mesodermal cell types. Using phylogenetic profiling, we increased the number of enhancers by incorporating orthologous but divergent sequences from other Drosophila species. Functional assays revealed that the diverged enhancer orthologs were active in largely similar patterns as their D. melanogaster counterparts, although there was extensive evolutionary shuffling of known TFBSs. We then built and trained a classifier using this enhancer set and identified additional related enhancers based on the presence or absence of known and putative TFBSs. Predicted FC enhancers were over-represented in proximity to known FC genes; and many of the TFBSs learned by the classifier were found to be critical for enhancer activity, including POU homeodomain, Myb, Ets, Forkhead, and T-box motifs. Empirical testing also revealed that the T-box TF encoded by org-1 is a previously uncharacterized regulator of muscle cell identity. Finally, we found extensive diversity in the composition of TFBSs within known FC enhancers, suggesting that motif combinatorics plays an essential role in the cellular specificity exhibited by such enhancers. In summary, machine learning combined with evolutionary sequence analysis is useful for recognizing novel TFBSs and for facilitating the identification of cognate TFs that coordinate cell type–specific developmental gene expression patterns

So what do we really mean when we say that systems biology is holistic?

Background: An old debate has undergone a resurgence in systems biology: that of reductionism versus holism. At least 35 articles in the systems biology literature since 2003 have touched on this issue. The histories of holism and reductionism in the philosophy of biology are reviewed, and the current debate in systems biology is placed in context. Results: Inter-theoretic reductionism in the strict sense envisaged by its creators from the 1930s to the 1960s is largely impractical in biology, and was effectively abandoned by the early 1970s in favour of a more piecemeal approach using individual reductive explanations. Classical holism was a stillborn theory of the 1920s, but the term survived in several fields as a loose umbrella designation for various kinds of anti-reductionism which often differ markedly. Several of these different anti-reductionisms are on display in the holistic rhetoric of the recent systems biology literature. This debate also coincides with a time when interesting arguments are being proposed within the philosophy of biology for a new kind of reductionism. Conclusions: Engaging more deeply with these issues should sharpen our ideas concerning the philosophy of systems biology and its future best methodology. As with previous decisive moments in the history of biology, only those theories that immediately suggest relatively easy experiments will be winners