MyMedR

Unusual form of superficial spreading microinvasive squamous cell carcinoma of uterine cervix involving the endometrium of uterus

Tan GC, Isa MR, Ng SP, Jamil YM

J Obstet Gynaecol Res, 2004 Oct;30(5):363-7.

PMID: 15327449

Microinvasive squamous cell carcinoma of the uterine cervix is a recognized entity and is defined as carcinoma with invasion of less than 5 mm penetration of the stroma and seldom metastasized. Our patient was a 70-year-old, multiparous woman who had a microinvasive, cervical, squamous cell carcinoma. The tumor had spread superficially into the entire endometrial cavity up to the fundus, totally replacing the columnar epithelium. This is an extremely rare phenomenon, with fewer than 20 cases reported so far in the literature.

Matched MeSH terms: Epithelium/pathology

Proliferating cell nuclear antigen (PCNA) expression in oral squamous cell carcinoma - an aid to conventional histological grading?

Zain RB, Sakamoto F, Shrestha P, Mori M

Malays J Pathol, 1995 Jun;17(1):23-30.

PMID: 8907001

Proliferating cell nuclear antigen (PCNA) is a well known marker for cell proliferation. It tends to accumulate in the late G1 and S-phase of the cell cycle. A monoclonal antibody (MoAb) against PCNA is now available and it can react with paraffin-embedded specimens. In the present study, PCNA immunohistochemical staining of 36 cases of oral cancer specimens obtained from surgery were investigated. The results showed differing nuclear staining patterns for PCNA in normal, hyperplastic and dysplastic epithelium, early cancer and 3 levels of differentiation for squamous cell carcinoma of the oral cavity. It appears that PCNA can be a useful marker in delineating normal epithelium and hyperplastic epithelium from dysplasia in the oral cavity. The use of PCNA staining may further emphasize the conventional histopathological grading of well-differentiated, moderately-differentiated and poorly-differentiated oral squamous cell carcinoma but is still dependent on basic criteria as observed without immunostaining. PCNA expression for all grades of squamous cell carcinoma are present at the deep, infiltrative margins.

Matched MeSH terms: Epithelium/pathology

Morphometric analysis of epithelial components and dentinoid formation in non-neoplastic calcifying odontogenic cyst

Ng KH, Siar CH

J Nihon Univ Sch Dent, 1995 Sep;37(3):156-62.

PMID: 7490609

Calcifying odontogenic cysts (COCs) represent a group of lesions that may be broadly classified into two main entities: cysts and neoplasms. In the present study 30 non-neoplastic cystic COCs were examined by a quantitative histological method in an attempt to calibrate the relative distribution of the type of epithelial lining, intensity of ghost cell formation and the amount of dentinoid present. The results showed that there are two main types of cystic COC: an odontoma-producing type and a non-odontoma-producing variant. Morphologically, tooth-like structures were a valid distinguishing feature, while morphometrically the odontoma-producing variant showed a greater amount of luminal and mural dentinoid as well as luminal ghost cells. Demographic analysis also revealed that the odontoma-producing COC occurred in younger patients and showed an even sex distribution, whereas the non-odontoma-producing type was seen in older patients and showed a predilection for females. Both subtypes were more prevalent in the Chinese population and occurred preferentially in the maxilla.

Matched MeSH terms: Epithelium/pathology

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: Epithelium/pathology

Immunohistochemical study of the distribution of S-100 protein in pleomorphic adenomas of minor salivary glands

Siar CH, Ng KH

J Nihon Univ Sch Dent, 1992 Jun;34(2):96-105.

PMID: 1380072

Twelve pleomorphic adenomas of minor salivary gland origin were examined for the distribution of S-100 protein, detected using the peroxidase-antiperoxidase (PAP) method. Strong S-100 protein immunoreactivity was noted in areas containing plasmacytoid cells, stellate and spindle cells against a myxochondroid or hyalinous stroma, and solid epithelial areas. Tubular and duct-like structures showed variable stainability. Stromal tissue and normal salivary glands were generally negative for S-100 protein. These findings were compared with those reported elsewhere.

Matched MeSH terms: Epithelium/pathology

Squamous odontogenic tumor

Yaacob HB

J Nihon Univ Sch Dent, 1990 Sep;32(3):187-91.

PMID: 2230962

The twenty-fifth reported case of squamous odontogenic tumor is presented. The patient was a 39-year-old Chinese Malaysian male. The lesion was asymptomatic and did not recur after excision. It is important to distinguish this type of lesion from squamous odontogenic tumor-like proliferation. The rest of Malassez is thought to be responsible for the histogenesis of the lesion. Better understanding will only be achieved when more cases are reported and studied.

Matched MeSH terms: Epithelium/pathology

Changes in the tissues adjacent to oral squamous cell carcinomas

Yeow CS

Dent J Malaysia Singapore, 1973 May;13(1):51-62.

PMID: 4521126

Matched MeSH terms: Epithelium/pathology

Desmoplastic variant of ameloblastoma in Malaysians

Ng KH, Siar CH

Br J Oral Maxillofac Surg, 1993 Oct;31(5):299-303.

PMID: 8218083

Seventeen cases are reported of desmoplastic variant of ameloblastoma of the jaws observed during the years 1967-1991. There were 12 females and 5 males, and these consisted of 7 Chinese, 6 Malays, 2 Indians, 1 Sikh and 1 Kadazan. Their ages at diagnosis ranged from 21-60 years with a mean of 36.6 years. There were 10 mandibular and 7 maxillary tumours. Of these, 14 cases involved the anterior segment with extension to the premolar region in 5 cases. 60% of cases were radiologically suggestive of fibro-osseous lesions. The main mode of treatment was resection and 1 case presented with recurrence. The findings of this study were compared with those of previous reports.

Matched MeSH terms: Epithelium/pathology

'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: Epithelium/pathology

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: Epithelium/pathology

The combined epithelial odontogenic tumour in Malaysians

Siar CH, Ng KH

Br J Oral Maxillofac Surg, 1991 Apr;29(2):106-9.

PMID: 2049349

The combined epithelial odontogenic tumour represents a hybrid lesion comprising primarily areas of adenomatoid odontogenic tumour intermixed with foci of calcifying epithelial odontogenic tumour. Five such cases retrieved from the files of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, and four others from the existing literature were analysed. A mean age of 18.8 years, a female preponderance (66.7%) with a male to female ratio of 1:2 and predilection for the mandible (55.6%) were observed. All cases were treated by conservative surgery and the lack of recurrence confirmed the innocuous nature of this lesion.

Matched MeSH terms: Epithelium/pathology

POLYPOIDAL CHOROIDAL VASCULOPATHY SECONDARY TO A STABLE CHOROIDAL NEVUS

Wong JG, Lai XJ, Sarafian RY, Wong HS, Smith JB

Retin Cases Brief Rep, 2016;10(3):221-4.

PMID: 26509999 DOI: 10.1097/ICB.0000000000000233

PURPOSE: Choroidal nevus is the most common ocular fundus tumor in adults. Previous studies have widely discussed the features of choroidal neovascularization secondary to nevus and its treatment options. Polypoidal choroidal vasculopathy (PCV) is an exudative chorioretinopathy that is often underdiagnosed. Clinical features, natural history, and treatment response of PCV are distinct from occult choroidal neovascularization. Polypoidal choroidal vasculopathy secondary to choroidal nevus has not been previously documented. We report a patient with a history of stable choroidal nevus who developed a polypoidal lesion at the edge of the nevus lesion.

METHODS: A white woman who presented with a choroidal nevus and clinical features of PCV was examined using fundoscopy, optical coherence tomography, fluorescein angiography, and indocyanine green angiography.

RESULTS: A polypoidal lesion with an associated branching vascular network adjacent to the nevus was demonstrated by optical coherence tomography, fluorescein angiography, and indocyanine green angiography. The patient was asymptomatic and was managed conservatively.

CONCLUSION: Our case showed that PCV developing in association with a stable choroidal nevus. Pathogenic mechanisms of this condition may include chronic degenerative or inflammatory changes at the level of the retinal pigment epithelium resulting in vascular changes. Unlike treatment of occult choroidal neovascularization secondary to nevus, optimal management of PCV secondary to nevus may vary. Indocyanine green angiography is the gold standard for the diagnosis of PCV and is a useful investigation in atypical choroidal neovascularization.

Matched MeSH terms: Retinal Pigment Epithelium/pathology

Effect of mixed infection of Mycoplasma gallinarum and Newcastle disease virus (F strain) on the tracheal epithelium of village chickens

Shah-Majid M

Res Vet Sci, 1996 Sep;61(2):176-8.

PMID: 8880993

The effects of a mixed infection of Mycoplasma gallinarum and Newcastle disease virus (F strain) on the tracheal epithelium of village chickens were investigated and observed by scanning electron microscopy. Day-old village chicks were vaccinated intranasally with F strain Newcastle disease virus and inoculated intratracheally on the same day with 10(8) colony forming units of M gallinarum. In another study the chicks were vaccinated and then infected with M gallinarum seven days later. The first group of chicks was euthanased three, seven, 10, 14 and 21 days after vaccination and infection and the vaccinated chicks were euthanased three, seven, 10 and 14 days after infection. In the chicks vaccinated and infected on the same day, major alterations to the tracheal epithelium were visible three days later. There were fewer ciliated cells and the borders of the non-ciliated cells were prominent. Several depressions had formed in the epithelial surface. At higher magnification, clumps of microvilli were visible on some of the non-ciliated cells. Seven days after vaccination and infection, the tracheal epithelium appeared normal, with an increase in the numbers of ciliated cells, although raised borders were observed on the non-ciliated cells in some areas. No clumping of microvilli or depressions in the epithelial surface were observed. In the chicks infected seven days after vaccination, the tracheal epithelium appeared normal with no visible changes on its surface.

Matched MeSH terms: Epithelium/pathology

Secretory proteostasis of the retinal pigmented epithelium: Impairment links to age-related macular degeneration

Paraoan L, Sharif U, Carlsson E, Supharattanasitthi W, Mahmud NM, Kamalden TA, et al.

Prog Retin Eye Res, 2020 11;79:100859.

PMID: 32278708 DOI: 10.1016/j.preteyeres.2020.100859

Secretory proteostasis integrates protein synthesis, processing, folding and trafficking pathways that are essential for efficient cellular secretion. For the retinal pigment epithelium (RPE), secretory proteostasis is of vital importance for the maintenance of the structural and functional integrity of apical (photoreceptors) and basal (Bruch's membrane/choroidal blood supply) sides of the environment it resides in. This integrity is achieved through functions governed by RPE secreted proteins, which include extracellular matrix modelling/remodelling, angiogenesis and immune response modulation. Impaired RPE secretory proteostasis affects not only the extracellular environment, but leads to intracellular protein aggregation and ER-stress with subsequent cell death. Ample recent evidence implicates dysregulated proteostasis as a key factor in the development of age-related macular degeneration (AMD), the leading cause of blindness in the developed world, and research aiming to characterise the roles of various proteins implicated in AMD-associated dysregulated proteostasis unveiled unexpected facets of the mechanisms involved in degenerative pathogenesis. This review analyses cellular processes unveiled by the study of the top 200 transcripts most abundantly expressed by the RPE/choroid in the light of the specialised secretory nature of the RPE. Functional roles of these proteins and the mechanisms of their impaired secretion, due to age and genetic-related causes, are analysed in relation to AMD development. Understanding the importance of RPE secretory proteostasis in relation to maintaining retinal health and how it becomes impaired in disease is of paramount importance for the development and assessment of future therapeutic advancements involving gene and cell therapies.

Matched MeSH terms: Retinal Pigment Epithelium/pathology

Fulltext Detrimental Effects of UVB on Retinal Pigment Epithelial Cells and Its Role in Age-Related Macular Degeneration

Mahendra CK, Tan LTH, Pusparajah P, Htar TT, Chuah LH, Lee VS, et al.

Oxid Med Cell Longev, 2020;2020:1904178.

PMID: 32855763 DOI: 10.1155/2020/1904178

Retinal pigment epithelial (RPE) cells are an essential part of the human eye because they not only mediate and control the transfer of fluids and solutes but also protect the retina against photooxidative damage and renew photoreceptor cells through phagocytosis. However, their function necessitates cumulative exposure to the sun resulting in UV damage, which may lead to the development of age-related macular degeneration (AMD). Several studies have shown that UVB induces direct DNA damage and oxidative stress in RPE cells by increasing ROS and dysregulating endogenous antioxidants. Activation of different signaling pathways connected to inflammation, cell cycle arrest, and intrinsic apoptosis was reported as well. Besides that, essential functions like phagocytosis, osmoregulation, and water permeability of RPE cells were also affected. Although the melanin within RPE cells can act as a photoprotectant, this photoprotection decreases with age. Nevertheless, the changes in lens epithelium-derived growth factor (LEDGF) and autophagic activity or application of bioactive compounds from natural products can reverse the detrimental effect of UVB. Additionally, in vivo studies on the whole retina demonstrated that UVB irradiation induces gene and protein level dysregulation, indicating cellular stress and aberrations in the chromosome level. Morphological changes like retinal depigmentation and drusen formation were noted as well which is similar to the etiology of AMD, suggesting the connection of UVB damage with AMD. Therefore, future studies, which include mechanism studies via in vitro or in vivo and other potential bioactive compounds, should be pursued for a better understanding of the involvement of UVB in AMD.

Matched MeSH terms: Retinal Pigment Epithelium/pathology

Notch4 overexpression in ameloblastoma correlates with the solid/multicystic phenotype

Siar CH, Nagatsuka H, Chuah KS, Rivera RS, Nakano K, Ng KH, et al.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2010 Aug;110(2):224-33.

PMID: 20659700 DOI: 10.1016/j.tripleo.2010.03.009

Notch signaling has been implicated in cell fate decisions during odontogenesis and tumorigenesis of some odontogenic neoplasms; however, its role in solid/multicystic (SA), unicystic (UA), and recurrent (RA) ameloblastoma remains unclear. The aim of this study was to determine Notch receptor and ligand expressions in these subtypes and to speculate on their significance.

Matched MeSH terms: Epithelium/pathology

Claudin expression and tight junction protein localization in the lining epithelium of the keratocystic odontogenic tumors, dentigerous cysts, and radicular cysts

Siar CH, Abbas SA

Oral Surg Oral Med Oral Pathol Oral Radiol, 2013 May;115(5):652-9.

PMID: 23601220 DOI: 10.1016/j.oooo.2013.02.013

The aim of this study was to evaluate the expression and localization of tight junction proteins (TJPs) or claudins in the keratocystic odontogenic tumor (KCOT) and to correlate with its biological behavior.

Matched MeSH terms: Epithelium/pathology

Peripheral ameloblastoma with clear cell differentiation

Ng KH, Siar CH

Oral Surg. Oral Med. Oral Pathol., 1990 Aug;70(2):210-3.

PMID: 2290651

This report details a case of mandibular peripheral ameloblastoma having a clear cell component. The latter consisted of ovoid cells with vacuolated or clear cytoplasm and vesicular or pyknotic nuclei that may be disposed as discrete clusters or show direct transition from typical acanthomatous areas. Comparison of this lesion with other odontogenic and nonodontogenic tumors that contain clear cells is discussed in the context of the differential diagnosis.

Matched MeSH terms: Epithelium/pathology

Plexiform granular cell odontogenic tumor: unicystic variant

Siar CH, Ng KH, Jalil NA

Oral Surg. Oral Med. Oral Pathol., 1991 Jul;72(1):82-5.

PMID: 1891247

Plexiform granular cell odontogenic tumor of the mandible has recently been described. The cardinal histopathologic feature, as its name suggests, is a monophasic plexiform pattern of granular cells; the principal tumor in the differential diagnosis is granular cell ameloblastoma. Unlike the two previously reported cases of plexiform granular cell odontogenic tumor, which occurred as solid tumors in elderly men, the lesion reported here is a unicystic variant occurring in a middle-aged woman.

Matched MeSH terms: Epithelium/pathology

Wu CL, Hsu WH, Chiang CD, Kao CH, Hung DZ, King SL, et al.

J. Toxicol. Clin. Toxicol., 1997;35(3):241-8.

PMID: 9140317 DOI: 10.3109/15563659709001207

BACKGROUND: Taking Sauropus androgynus, a Malaysian food, to reduce weight began as a fad in Taiwan in 1994. Some advocates of this fad developed pulmonary dysfunction. The aim of this study is to report the lung injury in patients taking Sauropus androgynus.

METHODS: From July 1995 to November 1995, we investigated 104 nonsmoking patients (one male and 103 females) with chest roentgenography, pulmonary function, test, and Technetium 99m-labeled diethylene triamine penta-acetate (Tc-99m DTPA) radioaerosol inhalation lung scintigraphy.

RESULTS: Among the 90 patients receiving Tc-99m DTPA inhalation lung scan, 46 (51.1%) patients had increased clearance of Tc-99m DTPA from lung and 20 (22.2%) patients had inhomogeneous deposition of the submicronic radioaerosol. Eighteen (18/100) patients had obstructive ventilatory impairment in pulmonary function test. Analyzing the results, we found that the patients with respiratory symptoms (n = 42) took more vegetables (p = 0.016), had increased clearance of Tc-99m DTPA (p = 0.010) and had lower FEV1 (p = 0.001), FEV1/FVC (p < 0.001), FEF25-75 (p = 0.001), VC (p = 0.002) and DLCO (p = 0.009) than the patients without respiratory symptoms (n = 62). FEV1 and FEV1/FVC were significantly reduced in patients with severe impairment of alveolar permeability. The cumulative dosage and duration of exposure were significantly associated with the reduction of FEV1 and FEV1/FVC.

CONCLUSION: The lung injury after taking Sauropus androgynus involves alveoli and/or small airways and is manifest as obstructive ventilatory impairment with inhomogeneous aerosol distribution and increased lung epithelial permeability.

Matched MeSH terms: Epithelium/pathology

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