Sustainable Collagen Film Preparation with Tannins Extracted from Moroccan Pomegranate Byproduct Varieties: Thermal, Structural, and Nanoscaled Studies.

Recently, obtaining collagen films using a cross-linking technique has been a successful strategy. The current investigation used six cross-linker extracts (CE) from six different pomegranate varieties' byproducts to make and characterize collagen-tannin films using acid-soluble collagen (SC). The polymeric film has a yellow hue after CE incorporation. Fourier transform infrared spectroscopy assessed the impact of CE and its successful interaction within the matrix. The shifts verify different interactions between extracts and collagen functional groups, where they likely form new hydrogen bonds, retaining their helix structure without damaging the matrix. Scanning electron microscopy was used to analyze the morphology and fiber size. The average diameter of the fibers was found to be about 3.64 µm. Thermal behaviors (denaturation and degradation) were investigated by thermogravimetric analysis. The weight losses of cross-linked films increased by around 20% compared to non-cross-linked ones. This phenomenon was explained by the absence of telopeptide sections in the collagen helical structure, typically reinforced by lysine and hydroxylysine covalent linkages. Nanoscaled observations were also accomplished using transmission electron microscopy (TEM) on SC and SC-CE. The TEM analysis confirmed the CE polymerization degree effect on the cross-linking density via the overlap sequences, ranging up to 32.38 ± 2.37 nm on the fibril. The prepared biodegradable collagen-tannin film showed higher cross-linking density, which is expected to improve the biomaterial applications of collagen films while exploiting the underrated pomegranate byproducts.

Telocytes inside of the peripheral nervous system - a 3D endoneurial network and putative role in cell communication.

In this paper, we developed the hypothesis concerning the reasons to assimilate endoneurial fibroblast-like dendritic phenotype [shortly termed endoneurial dendritic cells (EDCs)] to the endoneurial telocytes (TCs). We reviewed the literature concerning EDCs status and report our observations on ultrastructure and some immune electron microscopic aspects of the cutaneous peripheral nerves. Our data demonstrate that EDCs long time considered as fibroblasts or fibroblast-like, with an ovoidal nucleus and one or more moniliform cell extensions [telopodes (Tps)], which perform homocellular junctions, also able to shed extracellular microvesicles can be assimilated to TC phenotype. Sometimes, small profiles of basement membrane accompany to some extent Tps. Altogether data resulted from scientific literature and our results strength the conclusion EDCs are really TCs inside of the peripheral nervous system. The inner three-dimensional (3D) network of endoneurial TCs by their homo- and heterocellular communications appears as a genuine cell-to-cell communication system inside of each peripheral nerve.

Analysis of TP53 gene and particular infrastructural alterations in invasive ductal mammary carcinoma.

This study was conducted in order to determine the mutational status of TP53 gene and to determine some particular aspects from ultrastructural level in invasive mammary ductal carcinoma. The cellular signaling pathway involving the TP53 gene acts in biological deoxyribonucleic acid (DNA) repair processes and cell cycle arrest following a signal transmitted to the p53 protein when posttranslational changes occur in the cell due to stress induced in the cell by both intrinsic and extrinsic factors. Cellular stress activates the transcription factor function of the protein that initiates, as the case may be, either DNA repair or programmed cell death (apoptosis). The TP53 gene is commonly mutated in many human cancers and also has a highly polymorphic grade. To determine the mutational status of the exons 4-9 of the TP53 gene, we used extracted DNA from fresh breast tissue, and we analyzed it through direct sequencing. In mammary carcinoma, the mutation frequency of TP53 is running between 20-40% and, in regards the polymorphism, at least 14 different forms were identified, that are associated with cancer risk. The mutation type distribution showed a predominance of deletions and a reduced frequency of substitutions comparing with International Agency for Research on Cancer (IARC) database. Taken in consideration the importance of the tumor associated stroma in tumor development, we have also investigated some particular aspects at the infrastructural level of invasive mammary ductal carcinoma, notably concerning telocytes as tumor stroma interstitial cells by transmission electron microscopy analysis.

Molecular analysis of BRCA1 and BRCA2 genes by next generation sequencing and ultrastructural aspects of breast tumor tissue.

In this paper, we focus our interest on the dynamics alterations of the tumor-stroma interface at the ultrastructural level and to detect BRCA1 and BRCA2 mutations using next generation sequencing (NGS) of breast tumor tissue. Electron microscopic investigation revealed some peculiar infrastructural alterations of the tumor cells per se as well as of the tumor-stroma interface: invadopodia, shedding microvesicles, altered morphology and reduced number of telocytes, different abnormalities of the microvasculature. Tumor suppressor genes BRCA1 and BRCA2 are the genes with most hereditary predisposition to breast and ovarian cancer. An early identification of mutation within these genes is essential for determining classification and therapeutic approach to patients. Genetic tests used to determine mutations in BRCA1 and BRCA2 genes are laborious analysis methods which include, among others, NGS. We analyzed a total of eight samples, in which genomic DNA was amplified using Ion AmpliSeq panel BRCA1 and BRCA2. DNA libraries were created, amplified and sequenced with Ion Torrent Personal Genome Machine. The bio-information data obtained allow us to detect all known pathogenic mutation and uncertain polymorphisms.

Relevant infrastructural alterations in invasive pancreatic ductal adenocarcinoma.

In this study, we focus our interest on some peculiar infrastructural abnormalities detected in a pancreatic cancer case. Our electron microscopic observations underline the high plasticity of the pancreatic parenchyma cells. Tumor pancreatic exocrine lesions are represented by putative ductal and acinar cells, which proliferate and grow in a haphazard pattern, detrimental to endocrine counterpart. The tumor cells do not exhibit neither a pure ductular or ductal nor a pure acinar phenotype, but tumor lesions represented by neoplastic ductal cells with invasive growth are by far prevalently. In our pancreatic cancer case, electron microscopic investigation clearly shows that a plethora of the epithelial cells from the tumor lesions contain large areas of autophagy leading to the pleomorphic inclusions represented by fibrillary÷filamentous inclusions frequently associated with hyaline-amorphous material, and secondary lysosomes. One of the mostly striking and important finding in this report for a case of pancreatic cancer is the high fragility (extensive dissolutions) of plasma membrane of tumor cells leading to pseudo-syncytia formation. Desmosomal junctions are severely altered, almost missing. Plasma membranes showed shedding membrane vesicles. Extravasated inflammatory cells contribute to the dramatic and extensive destructive areas of epithelial cells as well as tumor-stroma counterpart, including the basement membrane. All above severe infrastructural abnormalities, especially down regulation of cell-cell and cell-extracellular matrix adhesions might result in aberrant cell behavior and, consequently, much care should be taken for the postoperatory patient evolution.

Particular molecular and ultrastructural aspects in invasive mammary carcinoma.

Electron microscopic investigations of invasive mammary carcinoma tumors revealed that intercellular junctions, namely desmosomes are severely altered; some desmosomes became internalized. Tumor cells, especially by their invadopodia, generate and disseminate membrane vesicles, including exosomes, inside of peritumoral stroma. Telocytes, a new described interstitial/stromal cell phenotype, considered to play important roles in cell signaling, exhibited a reduced number of hetero-cellular contacts, which suggests a possible perturbation of tissular homeostasis modulation. Signaling PIK3/Akt pathway plays an important role both in carcinogenesis and in proliferation, differentiation, and cell survival. Alteration of this pathway has been observed in many human cancers, often involving an increase in the activity of PIK3CA, p110α catalytic subunit of PI3K. Our study confirms the high prevalence of PIK3CA mutations in breast cancer. In accordance with the results of the largest previous studies, 87.5% of mutations detected by DNA direct sequencing were hot spot mutations, most of them located in the kinase domain. High percentage of mutations detected by high-resolution melting makes the assay an attractive choice for mutation scanning, especially, in samples with low percentage of tumor cell.

Relevant infrastructural alterations in a pancreatic neuroendocrine tumor: an insulinoma case.

In this study, we focus our interest on some peculiar infrastructural abnormalities detected in an insulinoma case. Tumor pancreatic endocrine cells proliferated detrimental to exocrine counterpart, so that extensive areas of prevalent ß-tumor cells can be seen. Two phenotypes of ß-tumor cells can be identified: (1) ß-tumor cells with full euchromatic and nucleolated nuclei and (2) ß-tumor cells with heterochromatic and shrink nuclei. Because of stroma alteration, including basement membrane, cell-extracellular matrix junctions are also compromised. The mostly striking and important finding in this report for a case of insulinoma is the high fragility of plasma membrane of both two phenotypes of ß-tumor cells. Cell-cell junctions, especially desmosomal junctions are severely altered, almost missing, plasma membranes showed shedding membrane vesicles and extensive dissolutions leading to pseudo-syncytia formation. Extravasated blood cells, including inflammatory cells contribute to the dramatic and extensive destructive areas of epithelial cells as well as stroma counterpart. Moreover, also the inner cell cytomembranes exhibit abnormalities: many ß-tumor cells have excessive dilatations of nuclear envelope and endoplasmic reticulum. All above severe infrastructural abnormalities, especially down regulation of cell-cell and cell-extracellular matrix adhesions and plasma membranes fragility might result in aberrant cell behavior and, consequently, much care should be taken for the postoperatory patient evolution.

Infrastructure of the telocytes from tumor stroma in the skin basal and squamous cell carcinomas.

In this paper, we focus our interest on the ultrastructure of telocytes (TCs) present inside of tumor-stroma in basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Tumor-stroma cooperation is necessary for tumor growth, invasive behavior and ectopic development of microtumors. There is a plethora of reports about the role of different stromal cell types in tumor evolution in the human body. In this line, almost nothing is known about the recently identified interstitial cell type called telocyte (TC). To our best knowledge, this is the first study to publish TCs in malignant tumors, namely BCC and SCC. Here, we described the infrastructural aspects of TCs as well as their relationships with other tumor stroma components. TC from the tumor stroma has cell body where the nucleus is located and exhibits two (rarely more) very long cell extensions of tens (over 60-100 µm) termed telopodes. A telopode appears as an alternation of very thin segments called podomers and dilated segments called podomes, which accommodate mitochondria, rough endoplasmic reticulum, cytoskeleton, caveolae, as well as coated vesicles. TCs establish homocellular junctions leading to a 3-D network inside of peritumoral stroma. TCs may play an important role in intercellular signaling via stromal synapses and shed microvesicle transfer. Comparative evaluation with normal dermal skin showed that telocytes from tumor stroma have a very restraint number of heterocellular junctions. The limitation of TCs heterocellular junctions suggests a possible involvement in induction of cell-cell communication alterations into the peritumoral stroma and, consequently, into the whole tumor mass.