Keratin Membrane Research Articles

Optimal utilization of waste wool: Preparation of bionic moisture-absorbing keratin membrane with hierarchical porous structure to harvest atmospheric moisture

In addressing the challenge of water scarcity, solar-assisted atmospheric water harvesting (SAWH) has emerged as a promising strategy. Here, we have designed a hierarchical regenerated wool keratin membrane (LiCl@CNMC) that mimics the natural Murray network. Carbon nano tube, serving as solar absorbers, are uniformly deposited on the hierarchical keratin membrane. Hygroscopic salt LiCl is impregnated into the keratin membrane to achieve exceptional water uptake capacity. Under simulated sunlight exposure, the surface temperature can reach 83.5 °C. Furthermore, the LiCl@CNMC membrane exhibits outstanding water absorption (0.79–2.67 g g−1) and desorption performance at 30–80 % RH. The bionic water-collecting membrane can carry out 12 adsorption–desorption cycles every day under outdoor conditions, and yielding 11.92 g g−1 day−1 of clean water. The design of regenerated keratin membrane not only provides a direct way for the regeneration and utilization of keratin materials, but also provides valuable guidance and inspiration for the preparation and application of natural polymers found.

Thiol-ene photoclick reaction: An eco-friendly and facile approach for preparation of MPEG-g-keratin biomaterial.

Wool keratin is a natural material with excellent properties, which is considered as scaffold biomaterial for tissue engineering. Polyethylene glycol can improve the mechanical properties of keratin materials because of its excellent biocompatibility and plasticity. In the present work, poly (ethylene glycol) methyl ether methacrylate (MPEGMA) was grafted onto keratin by thiol‐ene photoclick reaction. The results of FTIR and SDS‐PAGE verified the successful reaction between MPEGMA and keratin. Compared with the keratin, circular dichroism and XRD results showed that the β‐sheet ratio increased in MPEG‐g‐keratin. Additionally, it can be found that the exposure of keratin hydrophobic amino acids increased quickly and the micelle size became larger due to the introduction of MPEG from the results of fluorescence spectroscopy and particle size analysis. The MPEG‐g‐ keratin was formed into a membrane to further study the application of the modified keratin. Compared with the keratin membrane, the flexibility and biocompatibility of modified keratin have been improved. This work provides an eco‐friendly and facile approach for preparation of the keratin biomaterials.

Bilayered PLGA/Wool Keratin Composite Membranes Support Periodontal Regeneration in Beagle Dogs.

Regenerative procedures using guided tissue regeneration (GTR) membrane are presently well-established in periodontal therapy. In this study, bilayered poly(lactic-co-glycolic acid) (PLGA)/wool keratin (WK) composite membranes were prepared for use as GTR membrane by the solvent casting and electrospinning methods. Then, the composite membranes were used to evaluate the effects in guided tissue regeneration in beagle dogs. The results showed that the bottom layer (casting film) of the bilayered PLGA/wool keratin composite membranes was a compact PLGA/wool keratin membrane, and the upper layer (electrospun film) was a loose, porous, three-dimensional, and fibrous PLGA/wool keratin membrane (The wool keratin was at five different levels: 0, 0.5, 1, 2, or 4 wt %). The mechanical properties of the composites were significantly enhanced by the addition of wool keratin. The bilayered PLGA/1.0% wool keratin composite membranes presented the best values of ultimate strength and Young's modulus. All of the bilayered PLGA/wool keratin composite membranes showed high thermal and thermooxidative stabilities. The GTR results showed that the PLGA/1.0% wool keratin composite membranes could effectively promote the periodontal tissue regeneration after 12 weeks, and have a similar effect to the collagen membrane on the regeneration of the periodontal tissue. Thus, the bilayered PLGA/wool keratin composite membranes show great potential to meet the demand for GTR membrane. The study will serve as a foundation for further study of the PLGA/wool keratin membranes for GTR application and the therapy of periodontal disease.

Pure keratin membrane and fibers from chicken feather

In this research, keratin was extracted from the disposable chicken feather using l-cysteine as reducing agent. Then, it was re-dissolved in the sodium carbonate-sodium bicarbonate buffer, and the pure keratin membrane and fiber were fabricated by doctor-blade casting process and wet spinning method, respectively. Scanning electron microscopy (SEM), fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to characterize the chemical and physical properties of resulting powder, membrane and fiber. Compared with the raw chicken feather, the regenerated keratin materials retain its chemical structure and thermal stability, their relative crystallinity is a little different depend on the shaping method, which leads to the difference in moisture regain. The mechanical results show that tensile strength of the keratin membrane researches 3.5MPa, have potential application in biomedical fields. However, the keratin fiber presents low tenacity, i.e. 0.5cN/dtex, this problem should be solved in order to apply the new fiber in textile and material science.

Evaluation of Electrospinning Keratin Membrane with Gelatin Addition in Relation to Nerve Regeneration

Evaluation of Electrospinning Keratin Membrane with Gelatin Addition in Relation to Nerve Regeneration

Pulmonary blastoma: a clinicopathologic study of 3 cases and review of literature

Pulmonary blastoma (PB) is a rare biphasic neoplasm. Surgery is the preferred treatment with no consensus on the role of other therapies. We report the clinicopathologic features of PB in three patients. We reviewed the medical records of patients diagnosed with PB at Jackson Memorial Hospital, Miami, FL, since 2009–2012. The mean age at diagnosis was 53 years; two were male and both were heavy smokers. At diagnosis, all cases were symptomatic; two were stage IV with metastatic disease. Two out of three patients were treated with absolute curative surgical resection and both patients had no evidence of disease. Patient with stage IV and resection relapsed in 28 months, received chemotherapy and then radiation without response and died after 33 months. The other surgical patient has no evidence of disease at the end of this study. The patient with unresectable disease received chemotherapy alone attaining partial response. Pathologically, all cases showed biphasic morphology composed of epithelial and spindle cell stroma with mesenchymal differentiation. Immunohistochemical analysis revealed positivity in all cases for thyroid transcription factor, keratin, and epithelial membrane antigen in the epithelial component and negative in the mesenchymal component. In conclusion, surgery was the most beneficial intervention. Chemotherapy has shown mixed responses which is consistent with the literature. Targeted therapies should be explored as additional treatment options in PB.

Pulmonary blastoma: A clinicopathologic study of three cases.

e19140 Background: Pulmonary blastoma (PB) is a rare biphasic neoplasm representing 0.2-0.5% of pulmonary malignancies. Presentation ranges from asymptomatic to symptoms of advanced pulmonary tumors. Surgery is the preferred treatment with no consensus on the role of other adjuvant therapies. Methods: We report the clinicopathologic features of PB in 3 patients (pts). Retrospective review of medical records of pts diagnosed with PB at Jackson Memorial Hospital, Miami, FL since 2009. Staging performed using the 2009 AJCC system for NSCLC. Cases required pathological diagnosis before inclusion. Variables analyzed were demographics, clinicopathologic presentation, treatments and outcomes. Results: Mean age at diagnosis was 53 years old; 2 were male; Hispanic and Caucasian and 1 African American female. Both males were heavy smokers. At diagnosis, all cases were symptomatic; 1 had hypercalcemia of 12.9 mg/dL and 2 were stage IV with metastatic disease (bone and thyroid). 2/3 where treated with surgical resection and both achieved complete remission (CR); Pt with stage IV and resection relapsed in 28 months, received chemotherapy (3 cycles cisplatin/docetaxel) with progressive disease then radiation (37 Gy) without response and died. The other surgical patient remains in CR. The patient with unresectable disease received chemotherapy (6 cycles carboplatin/docetaxel) attaining partial remission. 2/3 patients remain alive at end of this study. Pathologically, all cases showed biphasic morphology composed of multiple glandular structures with atypical pseudostratified columnar epithelium and cellular stromal component. Immunohistochemical analysis revealed positivity in all cases for thyroid transcription factor (TTF-1), keratin, and epithelial membrane antigen (EMA) in the glandular component. Conclusions: All pts were symptomatic at diagnosis and 2 presented with metastatic disease. All pts had similar morphologically and immunophenotypically. Surgery was the most beneficial intervention in regard to CR and PFS. Chemotherapy has shown mixed responses, thus, larger studies are needed to define the role of chemotherapy in the adjuvant and palliative settings.

Preparation and Properties of Keratin/CMC Blend Membranes

In this work, the wool keratin solution was obtained by a reduction method, and mixed with sodium carboxymethyl cellulose (CMC) solution in order to prepare blend membranes. The structures and mechanical properties of the blend membranes with different keratin/CMC ratios were investigated. It was found the addition of CMC with good molding ability improved the smoothness and enhanced mechanical properties of membranes. The results of instrument analyses showed that the crystallinity, thermal stability and hydration performance of blend membranes were between those of pure keratin and CMC membranes. CMC exhibited good ability to improve the film-forming of keratin membrane.

The Characterization of Porous Structure of Frozen Wool Keratin Membrane

Use the keratin liquid which solved from wool with urea and 2-mercaptoethanol to prepare wool keratin porous membrane at different concentration and frozen temperature. Observe the morphological structure of the membrane by SEM and analyze the SEM pictures. The experimental results indicate that the liquid concentration and frozen temperature are inversely proportional to the porous membrane aperture and porosity, but proportional to the porous membrane density.

Regenerated keratin membrane to match the in vitro drug diffusion through human epidermis

This work aimed to develop membranes made of regenerated keratin and ceramides (CERs) to match the barrier property of the human stratum corneum in in vitro percutaneous absorption studies. The membrane composition was optimized on the basis of the in vitro drug diffusion profiles of ibuprofen, propranolol and testosterone chosen as model drugs on the basis of their different diffusion and solubility properties. The data were compared to those obtained using human epidermis.The ATR-FTIR and SEM analyses revealed that CERs were suspended into the regenerated keratin matrix, even if a partial solubilization occurred. It resulted in the membranes being physically stable after exposure to aqueous buffer and/or mineral oil and the fluxes of ibuprofen and propranolol from these vehicles through membranes and human skin were of the same order of magnitude. The best relationship with human epidermis data was obtained with 180μm-thick membrane containing 1% ceramide III and 1% ceramide VI. The data on the testosterone diffusion were affected by the exposure of the membrane to a water/ethanol solution over a prolonged period of time, indicating that such an organic solvent was able to modify the supermolecular organization of keratin and CERs.The keratin/CER membranes can represent a simplified model to assay the in vitro skin permeability study of small molecules.

In-vitro permeability of the human nail and of a keratin membrane from bovine hooves: prediction of the penetration rate of antimycotics through the nail plate and their efficacy.

In contrast to the partition coefficient octanol/water the molecular size of penetrating drugs has a noticeable influence on the permeability of the human nail plate and a keratin membrane from bovine hooves. The relationship between permeability and molecular weight is founded on well-established theories. The correlation between the permeability of the nail plate and that of the hoof membrane allows a prediction of the nail permeability after determination of the drug penetration through the hoof membrane. The maximum flux of ten antimycotics (amorolfine, bifonazole, ciclopirox, clotrimazole, econazole, griseofulvin, ketoconazole, naftifine, nystatin and tolnaftate) through the nail plate was predicted on the basis of their penetration rates through the hoof membrane and their water solubilities. An efficacy coefficient against onychomycoses was calculated from the maximum flux and the minimum inhibitory concentration. Accordingly, amorolfine, ciclopirox, econazole and naftifine are expected to be especially effective against dermatophytes, whereas in the case of an infection with yeasts only, amorolfine and ciclopirox are promising.

In-vitro permeability of the human nail and of a keratin membrane from bovine hooves: influence of the partition coefficient octanol/water and the water solubility of drugs on their permeability and maximum flux.

Penetration of homologous nicotinic acid esters through the human nail and a keratin membrane from bovine hooves was investigated by modified Franz diffusion cells in-vitro to study the transport mechanism. The partition coefficient octanol/water PCOct/W of the esters was over the range 7 to > 51,000. The permeability coefficient P of the nail plate as well as the hoof membrane did not increase with increasing partition coefficient or lipophilicity of the penetrating substance. This indicates that both barriers behave like hydrophilic gel membranes rather than lipophilic partition membranes as in the case of the stratum corneum. Penetration studies with the model compounds paracetamol and phenacetin showed that the maximum flux was first a function of the drug solubility in water or in the swollen keratin matrix. Dissociation hindered the diffusion of benzoic acid and pyridine through the hoof membrane. Since keratin, a protein with an isoelectric point of about 5, is also charged, this reduction can be attributed to an exclusion of the dissociating substance due to the Donnan equilibrium. Nevertheless, the simultaneous enhancement of the water solubility makes a distinct increase of the maximum flux possible. In order to screen drugs for potential topical application to the nail plate, attention has to be paid mainly to the water solubility of the compound. The bovine hoof membrane may serve as an appropriate model for the nail.

Uterine Tumors Resembling Ovarian Sex Cord Tumors: An Ultrastructural Analysis of 13 Cases

Uterine tumors resembling ovarian sex cord tumors (UTROSCT) are tumors of unclear histogenesis. The authors analyzed the ultrastructural features of 13 UTROSCT and correlated the findings with their immunohistochemical profile. Features included cells with frequent organoid, nested or cord-like arrangement (8), lumen formation (2; one of which showed surface microvilli), nuclei with irregular indentations (8), intermediate filaments (13), prominent paranuclear aggregates (5), cell junctions (9), desmosome-like junctions (2), tonofilaments (2), basal lamina (1), and cytoplasmic lipid droplets (7; prominent in 3). No dense bodies, subplasmalemmal densities or pinocytotic vesicles were seen. Ultrastructural epithelial differentiation was present in 2 tumors (positive for keratin or epithelial membrane antigen). Prominent lipid droplets correlated with sex cord markers positivity in 2 tumors. Ultrastructural features of smooth muscle differentiation were lacking and abundant paranuclear filaments did not correlate with myoid markers. UTROSCT are polyphenotypic neoplasms ultrastructurally with focal epithelial and variable sex cord-like differentiation. These findings suggest that UTROSCT may result from divergent differentiation in endometrial stromal tumors or represent a distinct group of uterine tumors with sex cord-like differentiation that are closer in histogenesis to ovarian sex cord stromal tumors.

Photothermal imaging in 3D surface analysis of membrane drug delivery

Various methods exist for research into the penetration process in the human nail plate and for investigation of dermal drug delivery. Application of spectroscopic methods in this scientific field is gaining importance. However, no method meets all demands of the large variety of applications. An alternative optical technique for the characterisation of samples is the photothermal spectroscopy. Photoacoustic techniques, photothermal radiometry, and photothermal beam deflection spectroscopy (PDS) are non-destructive analytical techniques that take advantage of the so-called photoacoustic and photothermal phenomena. PDS, in conjunction with an appropriate scanner, allows for depth profiling and is a promising technique for studies of three-dimensional drug diffusion into artificial and biological membranes. The objective of this article is to demonstrate the use of PDS imaging for pharmaceutical applications and drug delivery studies, with two experiments being used as examples: the follow-up of lateral dithranol penetration into an artificial membrane and depth-resolved measurement of the distribution of a model drug within a keratin membrane from bovine hoof.

In Vitro Transungual Permeation of Ciclopirox from a Hydroxypropyl Chitosan-Based, Water-Soluble Nail Lacquer

Commercial antimycotic nail lacquers are commonly based on water-insoluble resins. The present study was aimed at evaluating a novel, experimental nail lacquer (P-3051, Polichem SA, Lugano, Switzerland) based on the water-soluble film-forming agent hydroxypropyl chitosan (HPCH). The in vitro permeation of ciclopirox (CPX) from P-3051 and from a commercial, water-insoluble lacquer based on a vinyl resin (Penlac™, Aventis Pharma), was investigated using thin membranes obtained from bovine hooves, an accepted model for human nails. Similar CPX permeation fluxes at steady state through the membranes, but significantly different lag times were observed for P-3051 and Penlac™, when these were tested as dry films. The formulations thus appeared to influence only the time required by CPX to saturate the membrane, and not the final drug concentration gradient in the membrane. Permeation experiments performed on the same membranes and on hairless mouse skin with P-3051 and with a similar, HPCH-free vehicle (ERV), both tested in liquid form, disproved the possibility that HPCH might act as a permeation enhancer for CPX in either substrate. The possible reasons for the greater efficiency of the HPCH vehicle in terms of CPX transfer from the vehicle itself to the keratin membrane are discussed. This effect might be tentatively attributed to a particular affinity of HPCH for the membrane, resulting in intimate contact and strong adhesion of the HPCH lacquer to the keratin substrate.

Lymphoepitheliomalike Carcinoma

Two undifferentiated carcinomas of the endometrium with a prominent inflammatory reaction that were morphologically similar to nasopharyngeal cancers occurred in two patients who had postmenopausal bleeding. Tumor cells in both patients were large with indistinct cytoplasmic borders, vesicular nuclei, and prominent nucleoli, were arranged in sheets, in groups, or singly, and surrounded by an intense inflammatory component of lymphocytes, plasma cells, and karyorrhectic debris. Tumor cells were keratin (AE1/EA3) and epithelial membrane antigen (EMA) positive and leukocyte common antigen (LCA) negative. All three methods used for the detection of Epstein Barr virus (EBV) infection were negative. The first patient (International Federation of Gynecology and Obstetrics [FIGO] stage IVB) received chemotherapy and is alive and free of disease 9 months after diagnosis. The second patient (FIGO stage IIIC) received radiation therapy and chemotherapy 6 months after evidence of extensive retroperitoneal disease and died of disease 1 year after diagnosis. Tumors with these histologic features have been designated as lymphoepitheliomalike carcinomas (LELC) when they occur outside the nasopharynx. LELC can occur in the endometrium and, in this location, may not be associated with EBV infection.

Epithelial differentiation in intraspinal meningiomas

To investigate the epithelial features of intraspinal meningiomas, 25 intraspinal meningiomas and 25 intracranial meningiomas were examined for the presence of pseudopsammoma bodies with hematoxylin-eosin and periodic acid-Schiff staining. In addition, we investigated the expression of keratin and epithelial membrane antigen (EMA) by immunohistochemical methods. Pseudopsammoma bodies were found in 3 of 25 cases of intracranial meningiomas (12%), but no definitive pseudopsammoma bodies were observed the intraspinal meningiomas. Three cases (12%) of intraspinal meningiomas and 9 cases (36%) of intracranial meningiomas, including 3 cases with pseudopsammoma bodies, were immunoreactive for keratin. All 25 (100%) intracranial meningiomas and 20 of 25 (84%) intraspinal meningiomas were reactive for EMA. In the intraspinal meningiomas, 4 of 25 cases (16%) showed no reactivity for EMA. These findings suggest that the origin of certain cell components of meningiomas may be different according to the site of the tumor or that the nature of meningioma may be modified by the local environment.

Novel proteinous microcapsules from wool keratins

Sonication of an aqueous solution of wool keratins in the presence of an organic solvent such as toluene and xylene furnished the spherical microcapsules with about 2–10 mm in diameter and 0.05–0.1 mm in membrane thickness. When oil, fat and dyes were dissolved in the solvent, they were trapped within the vesicles in a yield of more than 90%. Although the other proteins such as a-lactalbumin gave the capsules of the similar dimensions, the keratin capsules were the most tight container. The barrier property of the keratin membrane was discussed in conjunction with high content of a cysteine residue in the keratins.

Parachordoma of the Buttock: An Immunohistochemical Case Study and Review

We report a case of parachordoma occurring in the buttock of a 43-year-old man, and review 20 cases of parachordoma reported in the English literature. The tumor in our case was grossly 3 cm in dimension, solid, lobulated and grayish-white in color. Microscopically, the tumor consisted of epithelioid and spindle cells, and fibromyxoid stroma. The epithelioid cells were immunohistochemically positive for vimentin, S-100 protein, neuron-specific enolase, keratin, carcinoembryonic antigen and epithelial membrane antigen, and negative for HMB45. These findings are similar to those for chordoma rather than extraskeletal myxoid chrondrosarcoma. Although the etiopathogenesis of parachordoma remains obscure, Schwann cells or some other neuron-related cell origin are suspected.

Transmembrane Electron Transfer across a Keratin Membrane and Lipid Bilayers Catalyzed by Manganese Porphyrin Dimers

Abstract Transmembrane electron transfer across S-cyanoethylated keratin (SCEK) and liposomal membranes catalyzed by (1), MnTTP-(CH2)n-MnP(COOMe)3, n = 2, 3, 12 showed that an enhanced electron transfer was observed especially when n = 2 or 3 on (1) in these membranes and imidazole was present.