Single Layer Of Cuboidal Cells Research Articles

Morphogenetic events influencing corneal maturation, development, and transparency: Light and electron microscopic study.

The development of the cornea is a fascinating process. Its dual origin involves the differentiation of surface ectoderm cells and the migration of mesenchymal cells of neural crest origin. This research aimed to demonstrate the morphogenesis of the rabbit cornea from fetal to postnatal life using light- and electron microscopy, and immunohistochemical analysis. There were 27 rabbit embryos and nine rabbits used. The rabbit cornea begins its prenatal development on the twelfth day of gestation. The surface ectoderm differentiates into the corneal epithelium on day 13. Intriguingly, telocytes were visible within the epithelium. The secondary stroma develops on the sixteenth day of gestation by differentiation of keratocytes. At the age of 2 weeks, the lamellae of collagenous fibers become highly organized, and the stroma becomes avascular, indicating that the cornea has become transparent. Bowman's membrane appears on day 23 of pregnancy and disappears on day 30. The Descemet's membrane appears at this time and continues to thicken postnatally. The corneal endothelium appears on the twentieth gestational day as double layer of flattened cells and becomes a single layer of cuboidal cells on day 30. The spaces between the endothelial cells resemble craters. VEGF immunohistochemical expression increases over the course of development, reaching its peak in the first week after birth before decreasing in all corneal layers and becoming negative in the stroma. In conclusion, numerous morphogenetic events contribute to corneal maturation and transparency, allowing the cornea to perform its vital functions.

Papillary renal neoplasm with reverse polarity: A clinicopathological and molecular genetic characterization of 16 cases with expanding the morphologic spectrum and further support for a novel entity.

Papillary renal neoplasm with reverse polarity (PRNRP) is a recently described, rare renal tumor that differs clinically, morphologically, and molecularly from papillary renal cell carcinoma (RCC). To further characterize the pathological spectrum of this rare tumor, in this study, we retrospectively identified 16 cases of PRNRP from three institutions to comprehensively investigate the clinicopathological and molecular genetic features, using immunohistochemistry (IHC), fluorescence in-situ hybridization (FISH), and targeted next-generation sequencing (NGS). The patients included nine men and seven women, with age ranging from 47 to 80 years (median = 67.5 years, mean = 65 years). The tumor size ranged from 0.4 to 9.5 cm in the greatest dimension (median = 1.8 cm, mean = 2.6 cm). Most tumors (12/16) were incidentally identified by imaging studies. By AJCC stage, 15 were categorized as pT1 and 1 was pT2. Follow-up showed no recurrences, metastases, or disease-related deaths in all the 16 patients. Grossly, 14 cases demonstrated at least a partially cystic appearance. Microscopically, all PRNRPs except 1 (case 13) were composed predominantly of thin, branching papillary architecture covered by a single layer of cuboidal cells with finely granular cytoplasm, and low-grade nuclei typically located toward the apical surface away from the basement. Case 13 consisted mostly of solid, densely packed tubules with only a minor papillary component (5%). Other commonly seen histological features included hyalinized or edematous papillae (n = 11), lymphocyte aggregation in fibrovascular cores (n = 10), mast cell infiltration (n = 8), and intralesional hemorrhage (n = 7). Uncommonly seen histological features included lymphoid cuff (n = 4), hemosiderin deposition (n = 5), foci of clear cell change (n = 4), intracytoplasmic vacuoles (n = 4), eosinophilic hobnail cells (n = 2), and infarct-type necrosis (n = 1). Two PRNRPs were concurrent with ipsilateral clear cell papillary RCC and clear cell RCC, respectively. By IHC, the tumors were consistently positive for GATA3, CK7, and PAX8. Fourteen out of 16 tumors showed a basolateral-membranous E-cadherin expression pattern, and 12/16 cases were positive for 34βE12.The expression of AMACR, CD10, and vimentin was either absent or only weak and focal. By targeted NGS, 13/14 evaluated PRNRPs harbored KRAS missense mutations involving c.35G>T resulting in p.G12V (7/13), c.35G>A resulting in p.G12D (4/13), and c.34G>T resulting in p.G12C (2/13). By FISH, 1/15 had gains of chromosomes 7 and 17, and 2/8 male cases had deletion of chromosomes Y. In conclusion, our study confirms that PRNRP is an indolent renal cell neoplasm with unique morphology, consistent immunohistochemical profile, and recurrent KRAS mutation. Our study expands the morphologic spectrum of PRNRP and provides further evidence supporting it as a novel entity.

Ultrastructural Characterization of Salivary Glands, Alimentary Canal and Malpighian Tubules of the Red Shield Bug Carpocoris mediterraneus Tamanini, 1958 (Heteroptera, Pentatomidae).

In this study, the gut structure and excretory system of Carpocoris mediterraneus which is phytophagous insect, were described with light and electron microscopies and discussed in relation to other Heteroptera species. The salivary system has two principal and accessory salivary glands, two principal and accessory gland ducts. The salivary gland and duct wall have a single layer of cuboidal cells. The duct lumen is surrounded by a thick intima layer. In the cytoplasm of the epithelial cells are seen vesicles. The gut includes fore, mid, and hindguts. The foregut consists of a long narrow tubular pharynx which opens into a slightly wider esophagus. The esophagus is thin walled and in turn opens into the midgut. The midgut has four regions (V1–V4). V1–V4 walls have a monolayered epithelium. V1 epithelium is double-nucleated. V1 cytoplasm contains numerous vesicles, secretory granules, spherocrystals, and cytoplasmic inclusions. Rod-shaped bacteria are seen in V4 lumen. The hindgut has pylorus and rectum. Malpighian tubules were attached in the pylorus. Malpighian tubules have a single-layer cuboidal epithelium. In their lumen, there are spherocrystals. The rectum wall has a monolayer of squamous epithelium and muscle layer. Numerous bacteria and uric acid crystals are seen in its lumen.

Biphasic squamoid alveolar renal cell carcinoma: Cytologic features of a rare entity

Biphasic squamoid alveolar renal cell carcinoma is a newly described rare morphologic variant of papillary renal cell carcinoma. Its characteristic histomorphology and immunophenotype have been well described in the literature. Namely, BSARCC is composed of a dual-cell population with nests of larger squamoid cells surrounded by a single layer of cuboidal cells in alveolar arrangements. Invariably, the squamoid component expresses cyclin D1. More recently, MET alterations have been identified within a subset of BSARCC, raising the possibility for targeted MET inhibitor therapy. To the best of our knowledge the cytomorphologic features of BSARCC have yet to be described. Herein we correlate the cytologic features (percutaneous image-guided fine needle aspiration) of BSARCC to its corresponding histomorphology and immunophenotype (core needle biopsy).

Choroid plexus papilloma in a free ranging eared dove (Zenaida auriculata)

Choroid plexus tumors (CPT) are rare neoplasms and histologically classified as choroid plexus papilloma (CPP), atypical choroid plexus papilloma (APP), and choroid plexus carcinoma (CPC). These neoplasms have been described in humans, domestic animals (canine, feline, equine, caprine) and some wild animals (cetaceans and Psittacidae birds). To our best knowledge, herein we report the first CCP in a free-ranging eared dove (Columbiformes; Zenaida auriculata, de Murs 1847). Histologically, the ventricle was dilated, with a papillary proliferation (arboriform pattern) in topography of CP. The neoplasm was well-differentiated, composed by a single layer of cuboidal cells, anchored in a delicate fibrovascular stroma. The neoplastic cells exhibited moderate stroma, with well-defined borders and round nuclei, with vesicular chromatin and inconspicuous nucleoli. Mitotic activity was low (<1 mitosis per 10 high-power fields). Immunohistochemistry for cytokeratin markers (AE1/AE3 antibody) were implemented, however, both neoplastic cells and normal epithelial tissues do not show immunoreactivity.

The kidney of the Nodularia freshwater mussel has a larger filtration-size and counter-current system with improved water excretion compared with the seawater mussel Mytilus.

ABSTRACTHistological studies and magnetic resonance imaging were employed to analyze the kidney structure and function of the freshwater mussel, Nodularia douglasiae. The Nodularia kidney consists of proximal, intermediate and distal tubules. The epithelia of the renal tubules were composed of a single layer of cuboidal cells. The proximal and distal tubules run in opposite directions underneath the pericardial cavity. Molecular weight cut-off (MWCO) values for the kidney filtration were detected by MR tracer injections: gadolinium-diethylenetriaminepentaacetic acid (GdDTPA) at 0.55 kDa, an oligomer-based contrast agent (CH3-DTPA-Gd) at 2.2 kDa, as well as Gd-DTPA-polylysine at 10, 22, and 110 kDa. The T1w-MRI intensity and T1 relaxation rate (R1) of the pericardial cavity and renal tubules increased with tracers smaller than 10 kDa. The other tracers showed only minimal or no increase. Thus, we concluded that the MWCO of the kidney is 22 kDa, 50 times larger than that for the Mytilus living in seawater. Since the R1 values of the renal tubules were similar to those of the pericardial cavity, the kidney did not concentrate filtrated tracers. The slow decay of the magnetic resonance (MR) tracers from the renal tubules indicated a low filtration rate, suggesting that the counter-current system reabsorbs useful solutes without reabsorption of water. The higher MWCO may be beneficial to maintain the tubular oncotic pressure and allow excretion of excess water. In conclusion, a main renal function of the freshwater mussel is the excretion of water, opposite to that of the seawater mussel and vertebrates, which preserve water.

Two cases of non-mucinous cystadenomas of the pancreas with pancreatobiliary phenotype and ovarian-like stroma

BackgroundDiagnosis of cystic tumor of the pancreas is based on the World Health Organization criteria that classify pancreatic cystadenomas into four types: intra-ductal papillary mucinous neoplasms, mucinous cystic neoplasms (MCNs), serous cystic neoplasms, and solid pseudo-papillary neoplasms depending on their secretion and presence of ovarian-like stroma. Recently, Albores-Saavedra identified non-mucinous cystadenomas of the pancreas with pancreato-biliary phenotype and ovarian-like stroma. This precipitated examination of the proportions of these rare tumors in patients treated at Tokushima University Hospital.Case presentationCase 1 was a 40-year-old woman with a cystic tumor in the tail of the pancreas. Computed tomography (CT) revealed a diffuse and non-enhanced cystic tumor in the tail of the pancreas. This tumor was diagnosed as a simple cyst at this point. However, 2 years later, the tumor had increased in size by 3 cm. Thus, laparoscopic distal pancreatectomy was performed. The content of the cyst was serous. The epithelial cells were lined with a single layer of cuboidal cells and the tumor had ovarian-like stroma pathologically. The final pathological diagnosis was non-mucinous cystadenoma of the pancreas with ovarian-like stroma.In Case 2, a cystic tumor in the pancreas was found by medical examination in a woman in her sixties who presented without symptoms. CT showed a 1.5-cm cystic tumor in the tail and body of the pancreas and a septum in the cyst. Nine years later, the tumor had grown to 2.4 cm in diameter and had a clear septum in the cyst. This tumor was diagnosed preoperatively as MCN. Thus, laparoscopic distal pancreatectomy was performed. The cyst contained serous fluid. Microscopic examination showed no ovarian-like stroma and the epithelial cells were lined by a single layer of cuboidal cells. The final pathological diagnosis was non-mucinous cystadenoma of the pancreas with ovarian-like stroma.ConclusionsAccurate preoperative diagnosis of this type of pancreatic cystic tumor may be difficult, although it occurs more often than expected. Non-mucinous cystadenomas of the pancreas with ovarian-like stroma need to be considered as a differential diagnosis.

A retrospective study on ovarian cystectomy

The ovaries are paired gonads in females and are concerned with germ cell maturation, storage and its release. The ovaries are also concerned with steroidogenesis. Ovary is covered by a single layer of cuboidal cells known as germinal epithelium. As per the clinical features of the benign ovarian tumors, benign tumors predominantly manifest in late reproductive age. Methods: This is a retrospective study, where 64 cases of ovarian cyst during the period of Jan 2017 to Jan 2018 at Department of Obstetrics and Gynaecology, KVG Medical College and Hospital, Sullia were included in the study. Analysis of the ovarian cyst cases during this period was done to know the histopathology and clinical symptoms of patients who required the surgery for ovarian cysts. Another objective was to compare the clinical symptoms, ultrasonographic features and histopathology of patients who required the surgery for ovarian cysts. 46 cases were operated laparoscopically and patients who had large mass and unfit for laparoscopic surgery underwent conventional laparotomy. Results: As we analysed retrospectively these 64 cases, there were 30 (46.8%) cases of benign cystic ovarian tumors, of which 12 (18.75%), cases were serous cystadenoma which was the commonest of all in this study. This was followed by mature cystic teratoma in 11 (17.1%) and mucinous cystadenoma 6 (9.37%). We came across only one (1.23%) case of malignant ovarian tumor, which was found in a postmenopausal woman. Borderline malignancy was encountered in 1 patient (1.56%), which was a borderline mucinous tumor. Conclusions: Benign cystic ovarian tumors were common cause of ovarian cysts and of which serous cystadenoma was the commonest. Patients presented with vague symptoms, hence clinical symptoms could not differentiate between the type of cyst. Ultrasonography and histopathology helps us to arrive to definitive diagnosis but however histopathology gives us the final diagnosis.

Gross and Microanatomical Study of the Cornea in Japanese Quail (Coturnix Coturnix Japonica)

The present study was carried out on cornea of the Japanese quail. The cornea was the transparent, non-vascular structure and slightly curved front part of the eye and it covers the anterior chamber, iris and pupil in back side. The cornea was composed of anterior epithelium, bowman’s membrane, substantia propria, descemet’s membrane and posterior epithelium. The anterior epithelium was lined by non-keratinized stratified squamous epithelium of five to six layers of epithelial cells. The bowman’s membrane was observed as an acellular, transparent homogenous layer with numerous collagen fibres, which ran parallel to the corneal surface and placed beneath the anterior epithelium. The thickness of the substantia propria was found to be more than the other layers of the cornea and hence formed the greater part of the cornea. The posterior epithelium which lined the inner side of the descemet’s membrane consisted of a single layer of cuboidal cells. The thickness of the cornea ranged from 110.20±0.209μm to 156.39 ±1.244μm on the right eye ball and 109.70±0.182μm to 156.26±1.199μm on the left eye ball in two week-old to fourteen week-old Japanese quail.

Survivin and NAIP in Human Benign Prostatic Hyperplasia: Protective Role of the Association of Serenoa repens, Lycopene and Selenium from the Randomized Clinical Study.

Benign prostatic hyperplasia (BPH) treatment includes the apoptosis machinery modulation through the direct inhibition of caspase cascade. We previously demonstrated that Serenoa repens (Ser) with lycopene (Ly) and selenium (Se) reawakened apoptosis by reducing survivin and neuronal apoptosis inhibitory protein (NAIP) levels in rats. The aim of this study was to evaluate the effectiveness of Ser-Se-Ly association on survivin and NAIP expression in BPH patients. Ninety patients with lower urinary tract symptoms (LUTS) due to clinical BPH were included in this randomized, double-blind, placebo-controlled trial. Participants were randomly assigned to receive placebo (Group BPH + placebo, n = 45) or Ser-Se-Ly association (Group BPH + Ser-Se-Ly; n = 45) for 3 months. At time 0, all patients underwent prostatic biopsies. After 3 months of treatment, they underwent prostatic re-biopsy and specimens were collected for molecular, morphological, and immunohistochemical analysis. After 3 months, survivin and NAIP were significantly decreased, while caspase-3 was significantly increased in BPH patients treated with Ser-Se-Ly when compared with the other group. In BPH patients treated with Ser-Se-Ly for 3 months, the glandular epithelium was formed by a single layer of cuboidal cells. PSA showed high immunoexpression in all BPH patients and a focal positivity in Ser-Se-Ly treated patients after 3 months. Evident prostate specific membrane antigen (PSMA) immunoexpression was shown in all BPH patients, while no positivity was present after Ser-Se-Ly administration. Ser-Se-Ly proved to be effective in promoting apoptosis in BPH patients.

Anatomical and histological study of the kidneys and salt glands in great flamingos (Phoenicopterus roseus)

This study was designed to explain the anatomy and histology of kidneys and salt glands in Great Flamingos. Eight adult healthy Great Flamingos of both sexes have been used. The results showed that the kidneys in Great Flamingos consist of three separated lobes. The right kidney was longer 8.9±0.3 mm than the left kidney 8.4±0.4mm. The ratio of the kidneys weight to the total body weight was 0.39%. The salt gland was very large crescent shape, and occupied the supraorbital fossa and has 20.8±0.2mm long and 3.9±0.2mm in diameter. The volume of cortex was 60-70% and the medulla was 30-40%. Within the middle region of cortex there were numerous large corpuscles (mammalian type) and few of small corpuscles (reptilian type). There was a variation between the means diameters of mammalian type 59±1µm and reptilian type 42±0.9µm. The proximal and distal convoluted tubules and collecting ducts were lined by simple cuboidal epithelium and their means diameters were 46±0.9, 44±1 and 55.1±0.7µm, respectively. Within medulla the thick and thin segments were arranged at the peripheral zone of medullary cone while the collecting ducts were at the central part of cone and all were lined with simple cuboidal epithelium except thin segments were lined with squamous cells. The salt gland were consisted of lobules surrounded by thick connective tissue capsule and each has mass of branched tubuloacinar secretory unites. The latter were made up by single layer of cuboidal cells. The tubules lead into central duct lined by double layer of cuboidal cells while the main duct lined with stratified cuboidal epithelium. The secretory units of salt gland gave negative reaction to PAS and combined AB (pH 2.5) and PAS stains and this indicate the absence of neutral mucosubstances. The results concluded that the kidneys in great flamingo was small size organ with low relative weight in compare to birds size and the salt glands was active organ.

Nonmucinous Cystadenomas of the Pancreas With Pancreatobiliary Phenotype and Ovarian-Like Stroma

Among 31 benign cystic neoplasms of the pancreas diagnosed as mucinous cystadenomas, we identified 9 (29%) cases of nonmucinous cystadenomas with a pancreatobiliary phenotype and an ovarian-like stroma. Although both cystic tumors belong to the same family, they should be separated because their epithelial lining and cyst fluid are different. The lining cells of the nonmucinous cystadenomas consisted of a single layer of cuboidal cells, similar to the epithelial cells of the normal pancreatic ducts, and were not dysplastic (90%-100% of the lining cells). The cyst fluid was described as serous or clear. The remaining 22 classical mucinous cystadenomas, lined predominantly by mucinous and foveolar epithelium, revealed focal pancreatobiliary epithelium in 86% of the cases, and 6 pancreatic invasive mucinous cystadenocarcinomas failed to show pancreatobiliary differentiation. We believe that these nonmucinous cystadenomas of the pancreas represent a distinctive subset of cystic neoplasms of the pancreas that probably have no malignant potential.

Na+ dependent acid-base transporters in the choroid plexus; insights from slc4 and slc9 gene deletion studies

The choroid plexus epithelium (CPE) is located in the ventricular system of the brain, where it secretes the majority of the cerebrospinal fluid (CSF) that fills the ventricular system and surrounds the central nervous system. The CPE is a highly vascularized single layer of cuboidal cells with an unsurpassed transepithelial water and solute transport rate. Several members of the slc4a family of bicarbonate transporters are expressed in the CPE. In the basolateral membrane the electroneutral Na+ dependent Cl−/HCO3− exchanger, NCBE (slc4a10) is expressed. In the luminal membrane, the electrogenic Na+:HCO3− cotransporter, NBCe2 (slc4a5) is expressed. The electroneutral Na+:HCO3− cotransporter, NBCn1 (slc4a7), has been located in both membranes. In addition to the bicarbonate transporters, the Na+/H+ exchanger, NHE1 (slc9a1), is located in the luminal membrane of the CPE. Genetically modified mice targeting slc4a2, slc4a5, slc4a7, slc4a10, and slc9a1 have been generated. Deletion of slc4a5, 7 or 10, or slc9a1 has numerous impacts on CP function and structure in these mice. Removal of the transporters affects brain ventricle size (slc4a5 and slc4a10) and intracellular pH regulation (slc4a7 and slc4a10). In some instances, removal of the proteins from the CPE (slc4a5, 7, and 10) causes changes in abundance and localization of non-target transporters known to be involved in pH regulation and CSF secretion. The focus of this review is to combine the insights gathered from these knockout mice to highlight the impact of slc4 gene deletion on the CSF production and intracellular pH regulation resulting from the deletion of slc4a5, 7 and 10, and slc9a1. Furthermore, the review contains a comparison of the described human mutations of these genes to the findings in the knockout studies. Finally, the future perspective of utilizing these proteins as potential targets for the treatment of CSF disorders will be discussed.

Paratesticular endometriosis in a man with a prolonged hormonal therapy for prostatic carcinoma

A rare case of paratesticular endometriosis in a 69-year-old male with prostatic carcinoma, who had a history of 9-year hormonal therapy, is presented. The lesion was a multilocular cyst, 5.2 cm × 3.1 cm × 3.0 cm in size, in the left paratestis. The cysts were lined by a single layer of cuboidal cells. A small number of glands were scattered in the underling stroma composed of closely packed small round or ovoid cells with scant cytoplasm resembling endometrial stromal cells, and abundant capillaries. Hemosiderin deposits were observed. Immunohistochemically, the lining cells of the cysts and glands were positive for CAM5.2, vimentin and calretinin, and were negative for CD10, estrogen and progesterone-receptors, indicating mesothelial profiles. The stromal cells expressed vimentin, estrogen- and progesterone-receptors and CD10. The findings indicated stromal endometriosis associated with the tunica vaginalis. Mullerian or endometriotic metaplasia and stromal cell hyperplasia under the influence of prolonged estrogen therapy may be the mechanism of this lesion.

Combined adenomatoid tumor and well differentiated papillary mesothelioma of the omentum

Herein is reported a highly rare case of combined adenomatoid tumor and well differentiated papillary mesothelioma of the omentum. A 45-year-old Japanese man was incidentally found to have a mesenteric mass during abdominal ultrasonography. Grossly, a well-circumscribed and non-encapsulated tumor, measuring 24 × 23 × 22 mm, was located in the omentum with no obvious invasion to the surrounding stomach and pancreas. Microscopically, the tumor consisted of two histological distinct components; the majority of it showed irregular arrangement of numerous cysts lined by a single layer of flattened or epithelioid cells and the multifocal minor component exhibited prominent papillary protrusions lined by a single layer of cuboidal cells with relatively uniform nucleus. Immunohistochemically, the tumor cells were diffusely positive for cytokeratin (AE1/AE3), vimentin, calretinin, D2-40 and WT-1, and negative for epithelial membrane antigen (EMA), desmin, S-100 protein and CD68. Ki-67 labeling index of the tumor cells was <5%. The postoperative course was uneventful, though he has not received any adjuvant therapy. Despite the rarity, recognition of such combined cases of mesothelial lesions is important to prevent overdiagnosis.

Urothelial metaplasia of the seminal vesicles: a report of 2 cases

Although urothelial metaplasia has been reported in the fallopian tube, urothelium in the seminal vesicle has been rarely reported. We report 2 cases of urothelial epithelium in seminal vesicles from radical prostatectomy specimens. One case involved a 63-year-old patient with pT2c prostatic adenocarcinoma (Gleason pattern 3+4; total score, 7). The other case involved a 60-year-old patient with pT2c prostatic adenocarcinoma (Gleason pattern 4+3; total score, 7; with focal Gleason pattern 5). Representative sections of the left seminal vesicles from both patients demonstrated a portion of urothelial epithelium consisting of 3 to 8 cell layers, which included superficial (umbrella), intermediate, and basal cells. An abrupt transition from the normal single layer of cuboidal cells of seminal vesicle to multilayered urothelium was identified in 1 case, and circumferential urothelium was identified in the other case. No urothelial metaplasia was seen in the prostatic tissue. The histogenesis of urothelial metaplasia in the seminal vesicle is unclear, but it possibly is a reaction to mechanical irritation, inflammation, or infection, as has been proposed for urothelial metaplasia in the fallopian tube and squamous metaplasia of the pelvic peritoneum. Nevertheless, a rare congenital malformation cannot be ruled out as an etiology. Clinical follow-up of patients with urothelial cell metaplasia of the fimbriae suggests that it bears no biologic significance, yielding no instances of carcinoma. However, whether there will be an impact on fertility awaits further study.

Serous microcystic adenoma of the pancreatic head: Report of two cases and review of the literature

Serous microcystic adenomas (SMAs), also known as glycogen-rich cystadenomas, are uncommon exocrine tumors mainly involved in the body and tail of the pancreas. In this study, we report two SMA cases of the pancreatic head. In case 1, a 47-year-old woman was referred to our hospital for abdominal bloating and back pain; in case 2, a pancreatic space-occupying lesion was incidentally discovered in an asymptomatic 71-year-old female during an ultrasound. In both cases, a computer tomography scan showed well-demarcated and multilocular cysts in the head of the pancreas, and a central scar and calcifications were noted in case 1. During the exploratory laparotomies, the multiple cystic masses were found in the pancreatic head. A segmental resection of the pancreas and pancreatic jejunal anastomosis were performed. Histologically, the tumors were composed of tiny cysts that were filled with clear fluid and lined by a single layer of cuboidal cells with round, centrally located nuclei and clear cytoplasm, without cellular atypia. Immunohistochemical studies showed that the neoplastic cells were positive for cytokeratin 7 and vimentin but negative for synaptophysin and cytokeratin 20. A postoperative follow-up indicated no recurrence in the patients. We reviewed the literature regarding the etiology, clinical presentation, imaging characteristics, features and management of this lesion.

Comparative effects of estradiol, raloxifene, and genistein on the uterus of ovariectomized mice

To explore the uterine effects of administration of compounds that exert their bone-sparing functions through estrogen receptors, we administered 17beta-E2, raloxifene, or genistein to ovariectomized mice and analyzed the uterus weight and histology 4 weeks after beginning the treatments. Results indicated that raloxifene and genistein have partial agonistic properties on the uterus in estrogen-depleted mice, and that genistein induced apoptosis and several atypias in the glandular epithelium of endometrium, as demonstrated in hematoxylin-eosin-stained histological sections.

Fine structure of the retinal epithelium (RPE) of the emu (Dromaius novaehollandiae)

As part of an ongoing comparative fine structural study, the retinal pigment epithelium (RPE), choriocapillaris and complexus basalis (Bruch's membrane) in the emu (Dromaius novaehollandiae) have been investigated by light and electron microscopy. The RPE consists of a single layer of cuboidal cells joined basally by a series of tight junctions. Basally (sclerally) the RPE cells display numerous deep infoldings while apically (vitreally) plentiful microvillar processes interdigitate with the photoreceptor outer segments. Internally the epithelial cells show a large vesicular nucleus, plentiful smooth endoplasmic reticulum (SER) and numerous polysomes, but very little rough endoplasmic reticulum (RER). Numerous pleomorphic mitochondria are predominantly basally located. In the light-adapted specimens studied, the melanosomes of the RPE are almost exclusively located within the apical processes of these cells. Phagosomes and lysosome-like bodies are also present, as are myeloid bodies which often display ribosomes on their outer surface. Bruch's membrane (complexus basalis) is typical of avian species in that it is pentalaminate and the central lamina densa is displaced towards the choriocapillaris. The choriocapillaris endothelium is attenuated but only minimally fenestrated facing Bruch's membrane. Most of these fenestrations show a single-layered diaphragm but fenestrations with a double-layered diaphragm are not uncommon.

Phenotypic Modulation of Hamster Acinar Cells by Culture in Collagen Matrix

The aim of this study was to assess the effect of different culture conditions on the survival and morphological phenotype of cultured acinar cells. Acinar fragments isolated from hamster pancreas were embedded in rat-tail collagen. Four groups were established: Medium 1—5% NuSerum + basic medium (basic medium = DMEM/F12 supplemented with dexamethasone, 3-isobutyl-2-methylxanthine, and antibiotics); Medium 2—10% NuSerum + basic medium. Medium 3—Medium 2 supplemented with epidermal growth factor and cholera toxin; and Medium 4:—Medium 3 supplemented with soybean trypsin inhibitor. Freshly isolated acinar cells were retrieved morphologically intact. In Medium 1, more than 80% of cells retained a normal histological appearance at 34 days in culture. Immunostaining for amylase was observed at the apical pole of the cells. The remaining cells showed variable degrees of degeneration. In Medium 2, approximately 50% of acinar cells appeared normal at 34 days in culture, while the remainder were severely degenerated. A few cystic structures were also observed. Positive immunostaining for amylase was limited to the cells with a normal histological appearance. The cells grown in Media 3 and 4 had similar courses of morphological changes. After 8 days in culture, most acinar fragments disappeared and were replaced by cystic structures, lined by a single layer of cuboidal cells. Some amylase-positive immunoreactive cells were integral components of the cystic wall. Cellular amylase activity was a function of the different culture media, a more rapid decrease in amylase activity being observed in Media 3 and 4. Uptake of [3H]thymidine did not show any significant differences between the media. It was also found that the ductlike cells cultured in Medium 4 had a limited capacity to redifferentiate into acinar cells. This study shows that the acinar cell phenotype can be maintainedin vitrofor more than 1 month. This study also suggests that ductal-like epithelial structures arise from transformation of acinar cells.