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Fulltext Dentinogenic Ghost Cell Tumor in a Sumatran Rhinoceros

Salleh A, Zainuddin ZZ, Tarmizi RMM, Yap CK, Jeng CR, Zamri-Saad M

Animals (Basel), 2021 Apr 20;11(4).
PMID: 33923894 DOI: 10.3390/ani11041173

An adult female Sumatran rhinoceros was observed with a swelling in the left infraorbital region in March 2017. The swelling rapidly grew into a mass. A radiograph revealed a cystic radiolucent area in the left maxilla. In June 2017, the rhinoceros was euthanized. At necropsy, the infraorbital mass measured 21 cm × 30 cm. Samples of the infraorbital mass, left parotid gland, and left masseter muscle were collected for histopathology (Hematoxylin & Eosin, Von Kossa, Masson's trichrome, cytokeratin AE1/AE3, EMA, p53, and S-100). Numerous neoplastic epithelial cells showing pleomorphism and infiltration were observed. Islands of dentinoid material containing ghost cells and keratin pearls were observed with the aid of the two special histochemistry stains. Mitotic figures were rarely observed. All the neoplastic odontogenic cells and keratin pearls showed an intense positive stain for cytokeratin AE1/AE3, while some keratin pearls showed mild positive stains for S-100. All samples were negative for p53 and S-100 immunodetection. The mass was diagnosed as a dentinogenic ghost cell tumor.

Matched MeSH terms: Keratins
Fine needle aspiration cytology of undifferentiated embryonal sarcoma of the liver: a case report

Sharifah NA, Muhaizan WM, Rahman J, Zulfikar A, Zahari Z

Malays J Pathol, 1999 Dec;21(2):105-9.
PMID: 11068415

The cytological features of a rare case of undifferentiated (embryonal) sarcoma of the liver are presented. The cytology smears showed singly dispersed polygonal and spindle cells as well as loose clusters of cells held together in myxoid material. Neoplastic cells were generally large with round, oval or lobulated nuclei. The cytoplasm was variable in amount with ill-defined borders. Occasional multinucleated cells were also present. Hyaline globules were present on sections of the cell block. Immunohistochemical studies performed showed positivity for vimentin, cytokeratin and alpha-1-antitrypsin (AAT) in the tumour cells.

Matched MeSH terms: Keratins/analysis
Ultrasonic technology for value added products from feather keratin

Azmi NA, Idris A, Yusof NSM

Ultrason Sonochem, 2018 Oct;47:99-107.
PMID: 29908610 DOI: 10.1016/j.ultsonch.2018.04.016

Feather keratin is a biomass generated in excess from various livestock industries. With appropriate processing, it holds potential as a green source for degradable biopolymer that could potentially replace current fossil fuel based materials. Several processing methods have been developed, but the use of ultrasonication has not been explored. In this study, we focus on (i) comparing and optimizing the dissolution process of turkey feather keratin through sonication and conventional processes, and (ii) generating a biodegradable polymer material, as a value added product, from the dissolved keratin that could be used in packaging and other applications. Sonication of feather keratin in pure ionic liquids (ILs) and a mixture containing ILs and different co-solvents was conducted under different applied acoustic power levels. It was found that ultrasonic irradiation significantly improved the rate of dissolution of feather keratin as compared to the conventional method, from about 2 h to less than 20 min. The amount of ILs needed was also reduced by introducing a suitable co-solvent. The keratin was then regenerated, analyzed and characterized using various methods. This material holds the potential to be reused in various appliances.

Matched MeSH terms: Keratins/chemistry*
Nasopharyngeal undifferentiated carcinoma with sarcomatoid features: Pitfalls in the immunohistochemistry

Lee M, Son HJ, Kim NY, Kim SJ, Yu IK

Malays J Pathol, 2019 Aug;41(2):201-206.
PMID: 31427557

We present a case of an undifferentiated subtype of non-keratinizing squamous cell carcinoma (NK-SCC) with sarcomatoid features in the nasopharynx in a 69-year-old man who was difficult to diagnose due to spindle-shaped malignant cells. He was admitted because of a right nasal obstruction and right headache, and imaging revealed a heterogeneously enhanced irregularly shaped mass at the nasopharynx. Histopathologically, the tumour was partially organised, and the tumour cells were epithelioid or spindle-shaped. Initially, we erroneously diagnosed the tumour as an angiosarcoma owing to its false-negative immunoreaction for cytokeratins and a mistaken interpretation for CD31. After in situ hybridization for Epstein-Barr virus was positive, a consultation and additional immunostaining (including re-staining for cytokeratin with varying dilutions) were performed, and the diagnosis was revised to NK-SCC with sarcomatoid features. We believe that sarcomatoid features may be observed in nasopharyngeal carcinoma and in this case, immunostaining using various epithelial markers is necessary and careful attention should be paid to the interpretation of immunostaining.

Matched MeSH terms: Keratins
Human cytokeratin 1 plays a role in the interaction of Pteropine orthoreovirus with Hek293 cells but not HeLa cells

Siew ZY, Tan YF, Iswara RP, Wong SF, Wong ST, Tan BK, et al.

Microbes Infect, 2024;26(1-2):105243.
PMID: 38380604 DOI: 10.1016/j.micinf.2023.105243

Pteropine orthoreovirus (PRV) causes respiratory tract infections in humans. Despite its emergence as a zoonotic and respiratory virus, little is known about its cell tropism, which hampers progress in fully understanding its pathogenesis in humans. Hek293 cells are most susceptible to PRV infection, while HeLa cells are the least. Human cytokeratin 1 (CK1) was identified as the protein that interacts with PRV. The immunofluorescence assay and qPCR results revealed prior treatment with anti-CK1 may provide Hek293 cells protection against PRV. The KRT1-knockout Hek293 cells were less susceptible to PRV infection. Further study into the pathogenesis of PRV in humans is needed.

Matched MeSH terms: Keratins
Fulltext The eyes do not see what the mind does not know: an underreported feature in mature cystic teratoma of the ovary

Wong, Y.P., Tan, G.C.

Medicine & Health, 2018;13(2):223-228.
MyJurnal

Mature cystic teratoma is the commonest ovarian germ cell tumour which accounts for 70% of all benign ovarian neoplasms in the reproductive age groups. Being a pluripotent germ cell tumour, mature cystic teratoma has at least two out of three mature embryonic germ cell components: ectoderm, mesoderm and endoderm. The presence of multiple cystic spaces within the tumour wall, also known as pneumatosis cystoides-like appearance is rarely described but a characteristic feature in cystic teratoma of the ovary. Currently, there is little information concerning the mechanism of its formation. Herein, we described an unusual case of ovarian mature cystic teratoma in a 31-year-old pregnant female with multiple sieve-like areas resembling pneumatosis cystoides of the intestine. Macroscopic and histological examination of the ovary revealed features diagnostic of mature cystic teratoma. Intriguingly, multiple cystic spaces of variable sizes were found within the cyst wall histologically. They were lined partially or completely by foamy histiocytes and foreign body type multinucleated giant cells, exhibiting strong CD68 immunoreactivity. Vascular endothelial markers (CD31 and CD34) and epithelial marker (cytokeratin AE1/AE3) were negative. A diagnosis of mature cystic teratoma with pneumatosis cystoides-like feature was rendered. The patient was discharged well with no signs and symptoms of early labour. The etiopathogenesis of this intriguing histological feature is briefly discussed in this article.

Matched MeSH terms: Keratins
Cannon's disease: clinical and diagnostic implications: a case report

Ram S, Siar CH

Dent Update, 2004 Nov;31(9):557-9.
PMID: 15612463

Cannon's disease or white sponge naevus is a relatively rare genetically determined skin disorder. It is inherited as an autosomal dominant trait that displays a high degree of penetrance and expressivity. This article describes cases of Cannon's disease in a mother and her son.

Matched MeSH terms: Keratins/genetics
A clinicopathological and immunohistochemical study of the calcifying epithelial odontogenic tumour (Pindborg tumour) in Malaysians

Ng KH, Siar CH

J Laryngol Otol, 1996 Aug;110(8):757-62.
PMID: 8869610

We reviewed the clinicopathological characteristics of 13 cases of calcifying epithelial odontogenic tumour (CEOT) (Pindborg tumour) diagnosed in the Division on Stomatology, Institute for Medical Research, Kuala Lumpur, over a 29-year period. There were eight female and five male patients. These consisted of eight (61.5 per cent) Malays, three (23.1 per cent) Chinese, one (7.7 per cent) Indian and one (7.7 per cent) Melanau. Their ages at presentation ranged from 19-61 years (mean age, 31.8 years). There were 12 central and one peripheral CEOT. Of these, 76.9 per cent of cases were located in the maxilla, the remaining in the mandible. The commonest clinical diagnosis was a dentigerous cyst (66.7 per cent). Enucleation was the main mode of treatment. Histologically, sheets and strands of polyhedral epithelial cells containing eosinophilic, homogeneous globules with Liesegang rings were observed. One case also showed extensive calcification and clear cell differentiation. Immunohistochemistry revealed a variable keratin staining of the CEOT epithelium, confirming its heterogeneity.

Matched MeSH terms: Keratins/analysis
Characterization of keratin microparticles from feather biomass with potent antioxidant and anticancer activities

Sharma S, Gupta A, Chik SMST, Kee CG, Mistry BM, Kim DH, et al.

Int J Biol Macromol, 2017 Nov;104(Pt A):189-196.
PMID: 28596005 DOI: 10.1016/j.ijbiomac.2017.06.015

In the present study chicken feathers were hydrolyzed by chemical treatment in alkaline conditions. The pH value of feather hydrolyzed solution was amended accordingly the iso-electric precipitation. Two types of keratin microparticles KM1, KM2 were synthesized under acidic conditions at 3.5 and 5.5pH respectively. The synthesized keratin microparticles possessed uniform and round surface by scanning electron microscopy (SEM). The thermal degradation of microparticles were examined by thermogravimetry (TGA). Fourier transform infrared spectroscopy (FTIR) revealed that the extracted keratin retained the most of protein backbone. The microparticles were screened for their in vitro anticancer activities by SRB bioassay towards HeLa, SK-OV-3 and A549 cancer cell lines. Futhermore, their cytotoxicity towards healthy cell lines was analyzed having Malin Darby canine kidney (MDCK) cell lines along with in vitro antioxidant activity using DPPH and ABTS methods KM1 and KM2 showed 200.31±1.01 and 139.73±0.94, 214.16±0.29 and 153.92±0.61, 328.92±3.46 and 200.33±2.48μg/mL of IC50 levels against HeLa, SK-OV-3, and A549 cell lines, respectively. Moreover, KM1 and KM2 demonstrated significant antioxidant potency with IC50 levels 13.15 and 9.02μg/mL as well as 8.96 and 5.60μg/mL in DPPH and ABTS radical scavenging bioassay, respectively.

Matched MeSH terms: Keratins/pharmacology*; Keratins/chemistry*
Molecular strategies to increase keratinase production in heterologous expression systems for industrial applications

Yahaya RSR, Normi YM, Phang LY, Ahmad SA, Abdullah JO, Sabri S

Appl Microbiol Biotechnol, 2021 May;105(10):3955-3969.
PMID: 33937928 DOI: 10.1007/s00253-021-11321-y

Keratinase is an important enzyme that can degrade recalcitrant keratinous wastes to form beneficial recyclable keratin hydrolysates. Keratinase is not only important as an alternative to reduce environmental pollution caused by chemical treatments of keratinous wastes, but it also has industrial significance. Currently, the bioproduction of keratinase from native keratinolytic host is considered low, and this hampers large-scale usage of the enzyme. Straightforward approaches of cloning and expression of recombinant keratinases from native keratinolytic host are employed to elevate the amount of keratinase produced. However, this is still insufficient to compensate for the lack of its large-scale production to meet the industrial demands. Hence, this review aimed to highlight the various sources of keratinase and the strategies to increase its production in native keratinolytic hosts. Molecular strategies to increase the production of recombinant keratinase such as plasmid selection, promoter engineering, chromosomal integration, signal peptide and propeptide engineering, codon optimization, and glycoengineering were also described. These mentioned strategies have been utilized in heterologous expression hosts, namely, Escherichia coli, Bacillus sp., and Pichia pastoris, as they are most widely used for the heterologous propagations of keratinases to further intensify the production of recombinant keratinases adapted to better suit the large-scale demand for them. KEY POINTS: • Molecular strategies to enhance keratinase production in heterologous hosts. • Construction of a prominent keratinolytic host from a native strain. • Patent analysis of keratinase production shows rapid high interest in molecular field.

Matched MeSH terms: Keratins
Loss of PTEN expression is associated with IGFBP2 expression, younger age, and late stage in triple-negative breast cancer

Dean SJ, Perks CM, Holly JM, Bhoo-Pathy N, Looi LM, Mohammed NA, et al.

Am J Clin Pathol, 2014 Mar;141(3):323-33.
PMID: 24515759 DOI: 10.1309/AJCPR11DEAYPTUSL

OBJECTIVES: To investigate the association between PTEN loss and IGFBP2 expression in a series of triple-negative breast cancers and to relate this expression to basal cytokeratin expression and clinicopathologic features.
METHODS: One hundred and one formalin-fixed and paraffin-processed triple-negative breast cancer cases from the University of Malaya Medical Centre were tested immunohistochemically for cytokeratins 5/6 and 14, PTEN, and IGFBP2. The resulting slides were scored for proportion and intensity of staining.
RESULTS: Loss of tumor nuclear and cytoplasmic staining for PTEN occurred in 48.3% of cases and was significantly associated with younger age at diagnosis (47 years compared with 57 years in those without PTEN loss; P = .005). Independent predictors of PTEN loss were late stage at presentation (P = .026), cytokeratin 5/6 positivity (P = .028), and IGFBP2 expression (P = .042). High levels of IGFBP2 expression were seen in 32% of cases; an independent predictor of high levels was cytokeratin 14 negativity (P = .005). PTEN loss and high levels of IGFBP2 expression were associated with poorer survival, but neither of these trends was significant.
CONCLUSIONS: PTEN loss is a frequent event in triple-negative breast cancers and is significantly associated with younger age at onset of breast cancer, late stage, and IGFBP2 expression.

Matched MeSH terms: Keratins/metabolism
Serum IgA cross-reactivity between glycine-alanine repeat sequence of EBNA-1 and keratin or collagen in nasopharyngeal carcinoma

Mathew A, Cheng HM, Sam CK, Prasad U

Clin. Immunol. Immunopathol., 1994 May;71(2):164-8.
PMID: 7514112

Inhibition studies were carried out to study possible cross-reactivity between a peptide fragment of the Epstein-Barr virus nuclear antigen, EBNA-1, and keratin/collagen. The 20-amino acid peptide (pAG), derived from a glycine-alanine repeat region of EBNA-1, uniquely makes up about one-third of the viral protein and is a dominant IgA antigenic epitope in patients with nasopharyngeal carcinoma (NPC). A small percentage of normal human sera (NHS) also binds pAG and this reactivity is examined in this study. Ten percent (2/20) and 13.4% (2/15) of IgA-pAG-positive NPC sera and NHS, respectively, were significantly inhibited by keratin in a competitive ELISA system. Conversely, 31.6% (6/19) and 30.8% (4/13) of IgA-keratin-positive NPC sera and NHS, respectively, were significantly inhibited by pAG. This indicated minimum cross-reactivity between IgA serum antibodies to EBNA-1 and keratin. Using collagen as inhibitor, none of 18 and only 2/13 IgA-pAG-positive NPC sera and NHS, respectively, were inhibited. In the collagen ELISA system, only 2/19 (10.5%) and 4/25 (16%) of IgA-collagen-positive NPC sera and NHS, respectively, were inhibited with pAG. Therefore, cross-reactivity with collagen was also low. IgA-pAG-positive NHS may therefore not be a false positive phenomenon, but whether it may represent an early serological profile related to NPC carcinogenesis remains to be determined.

Matched MeSH terms: Keratins/immunology*
Fulltext Treatments of chicken feather waste

Cheong, Chooi Wei, Siti Aqlima Ahmad, Ooi, Peck Toung, Phang, Lai Yee

The Pertanika Journal of Scholarly Research Reviews, 2017;3(1):32-41.
MyJurnal

Feather waste is a potential renewable source to recover valuable products because it is being a rich source of keratin proteins and amino acids. It can be used to make feather meal, fertilizer and yarn sizing agent. Various treatments have been used to recover the protein from chicken feathers as the keratinous feathers cannot be easily degraded due to its tough structure. This paper reviews the existing treatment methods used to hydrolyze chicken feathers. The treatment methods for feather hydrolysis such as physical, chemical, biological and combined treatments as well as their advantages and challenges are highlighted. The effects of these treatments on feather hydrolysis are complex and vary in regards to the performance of feather hydrolysis and product yielded. Hence, it is important to choose an appropriate treatment method since the type of treatment applied affects the product yielded qualitatively and quantitatively. In addition, the economic assessment and environmental impact of the choice of treatment should be considered also.

Matched MeSH terms: Keratins
An immunohistochemical study of the lining epithelium of odontogenic keratocyst

Siar CH, Ng KH

J Nihon Univ Sch Dent, 1995 Sep;37(3):163-9.
PMID: 7490610

The lining epithelium of 15 cases of odontogenic keratocyst (OKC) was evaluated immunohistochemically. The peroxidase-antiperoxidase technique was applied to study the distribution of polyclonal keratin and S-100 protein while the indirect method was used to examine monoclonal vimentin and desmin reactivity. Consistent positive keratin staining was revealed in the lining epithelium of all 15 OKCs with additional intense staining in the stratum corneum. None of the cases showed vimentin or desmin reactivity within the lining epithelium elements. One of the 15 cysts studied showed positive S-100 protein staining in the nuclei of the lining epithelial cells. The pertinent literature on the immunophenotyping of the lining epithelium of OKC is reviewed.

Matched MeSH terms: Keratins/analysis
'Combined ameloblastoma and odontogenic keratocyst' or 'keratinising ameloblastoma'

Siar CH, Ng KH

Br J Oral Maxillofac Surg, 1993 Jun;31(3):183-6.
PMID: 7685634

Four cases of either combined occurrence of ameloblastoma and odontogenic keratocyst or a rare keratinising variant of ameloblastoma are presented. The cardinal histomorphologic characteristics are simultaneous occurrence of ameloblastomatous epithelial islands with central keratinisation and multiple keratinising cysts. Immunohistochemically the tumour elements were keratin positive and occasionally S-100 protein and desmin positive. Major differential diagnosis of these neoplasms are discussed.

Matched MeSH terms: Keratins/analysis
Unusual granular cell odontogenic tumor. Report of two undescribed cases with features of granular cell ameloblastoma and plexiform granular cell odontogenic tumor

Siar CH, Ng KH

J Nihon Univ Sch Dent, 1993 Jun;35(2):134-8.
PMID: 7692017

Granular cell ameloblastoma (GCA) is a well recognized variant of follicular ameloblastoma with extensive granular cell change. In contrast, plexiform granular cell odontogenic tumor (PGCOT) is a rare and recently described lesion characterized histologically by a monophasic plexiform pattern of granular cells. In this paper, two cases of an unusual granular cell odontogenic tumor exhibiting combined features of these two entities are described along with their immunohistochemical characteristics. The granular cells of both the GCA and PGCOT areas showed similar patterns of expression for keratin and S-100, which differed from those of typical ameloblastoma. No reactivity for desmin or vimentin was noted. The histomorphologic and immunohistochemical features of these hybrid tumors suggest that the granular cells present have a common origin, most probably the odontogenic epithelium.

Matched MeSH terms: Keratins/analysis
Patterns of expression of intermediate filaments and S-100 protein in desmoplastic ameloblastoma

Siar CH, Ng KH

J Nihon Univ Sch Dent, 1993 Jun;35(2):104-8.
PMID: 7692015

Seventeen cases of desmoplastic ameloblastoma were examined immunohistochemically. Immunoperoxidase techniques were applied for detection of keratin, desmin, vimentin and S-100 protein expression in these tumors. The tumor epithelium of desmoplastic ameloblastoma exhibited weak, focal, inconstant keratin staining, weak, variable expression of S-100 protein, desmin immunoreactivity of mild to moderate intensity and vimentin non-reactivity. The pertinent literature on the immunohistochemistry of ameloblastomas is briefly reviewed.

Matched MeSH terms: Keratins/analysis
Orthokeratinised odontogenic keratocysts in Malaysians

Siar CH, Ng KH

Br J Oral Maxillofac Surg, 1988 Jun;26(3):215-20.
PMID: 2456095

The records of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, Malaysia, were reviewed for the incidence of odontogenic keratocysts of the orthokeratinised variety, during the 20-year-period, 1967 to 1986. Nine cases were found. The clinical, histological and radiological features of these cases are reported. Many features were similar to previous reports of this entity but a peak incidence in the second decade of life, an almost even distribution in the maxilla and mandible, and a distinct predilection for the Chinese were observed. It is suggested that these features may be peculiar to Malaysians.

Matched MeSH terms: Keratins
Calcifying and keratinizing ameloblastoma of the maxilla

Siar CH, Ng KH

J Laryngol Otol, 1991 Nov;105(11):971-2.
PMID: 1722237

A case is described of ameloblastoma of maxilla presenting with numerous calcified keratin pearls. The significance of cellular variation in relation to the behavioural potential of the ameloblastoma in general is briefly discussed.

Matched MeSH terms: Keratins
Extraction and application of keratin from natural resources: a review

Chilakamarry CR, Mahmood S, Saffe SNBM, Arifin MAB, Gupta A, Sikkandar MY, et al.

3 Biotech, 2021 May;11(5):220.
PMID: 33968565 DOI: 10.1007/s13205-021-02734-7

Over recent years, keratin has gained great popularity due to its exceptional biocompatible and biodegradable nature. It has shown promising results in various industries like poultry, textile, agriculture, cosmetics, and pharmaceutical. Keratin is a multipurpose biopolymer that has been used in the production of fibrous composites, and with necessary modifications, it can be developed into gels, films, nanoparticles, and microparticles. Its stability against enzymatic degradation and unique biocompatibility has found their way into biomedical applications and regenerative medicine. This review discusses the structure of keratin, its classification and its properties. It also covers various methods by which keratin is extracted like chemical hydrolysis, enzymatic and microbial treatment, dissolution in ionic liquids, microwave irradiation, steam explosion technique, and thermal hydrolysis or superheated process. Special emphasis is placed on its utilisation in the form of hydrogels, films, fibres, sponges, and scaffolds in various biotechnological and industrial sectors. The present review can be noteworthy for the researchers working on natural protein and related usage.

Matched MeSH terms: Keratins

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