Journal of Cytology & Histology

Tumor stage is the main prognosticator of differentiated thyroid carcinomas, but it needs further stratification for multicentric neoplasms (most frequently papillary thyroid carcinomas, PTC), which frequently present as foci smaller than 1cm and are considered by default as high-risk tumors. Not all cases of multicentric PTC should be considered of high risk and they should be stratified to avoid unnecessary radioiodine ablation in selected cases. Currently, there are known variables for this stratification: size and number of tumor foci, clonal patterns, and specific markers of aggressive behaviour (infiltrative growth, BRAF mutation). In a near future, the identification of a gene expression pattern associated with a higher risk of recurrence would allow us to focus more aggressive treatment appropriately.

Myofibrils in vertebrate cardiac and skeletal muscles are characterized by groups of proteins arranged in contractile units or sarcomeres, which consist of four major components – thin filaments, thick filaments, titin and Zbands. The thin actin/tropomyosin-containing filaments are embedded in the Z-bands and interdigitate with the myosin-containing thick filaments aligned in A-bands. Titin is attached to the Z-band and extends upto the middle of the A-Band. In this mini review, we have addressed the mechanism of myofibril assembly as well as the dynamics and maintenance of the myofibrils in cardiac and skeletal muscle cells. Evidence from our research as well as from other laboratories favors the premyofibril model of myofibrillogenesis. This three-step model (premyofibril to nascent myofibril to mature myofibril) not only provides a reasonable mechanism for sequential interaction of various proteins during assembly of myofibrils, but also suggests why the dynamics of a thin filament protein like tropomyosin is higher in cardiac muscle than in skeletal muscles. The dynamics of tropomyosin not only varies in different muscle types (cardiac vs. skeletal), but also varies during myofibrillogenesis, for example, premyofibril versus mature myofibrils in skeletal muscle. One of the major differences in protein composition between cardiac and skeletal muscle is nebulin localized along the thin filaments (two nebulins/thin filament) of mature myofibrils in skeletal muscle cells, but which is expressed in a minimal quantity (one nebulin/50 actin filaments) in ventricular cardiomyocytes. Interestingly, nebulin is not associated with premyofibrils in skeletal muscle. Our FRAP(Fluorescence Recovery After Photobleaching) results suggest that tropomyosin is more dynamic in premyofibrils than in mature myofibrils in skeletal muscle, and also, the dynamics of tropomyosin in mature myofibrils is significantly higher in cardiac muscle compared to skeletal muscle. Our working hypothesis is that the association of nebulin in mature myofibrils renders tropomyosin less dynamic in skeletal muscle.

Horses have always sparked social and economic interest, awakening in the scientific community an interest in embryology and reproductive biology. To date, little is known about horse embryology because this species has several morphological and physiological characteristics that are peculiar to its own reproductive process. This study describes morphological aspects of developing cardiorespiratory apparatus in equine embryos and fetuses during 20-115 days of gestation. At 21 days, the equine embryo had a forming heart with two chambers and a distinct atrium and ventricle. There was a clear cellular protuberance in the lumen of both chambers and in the region of the endocardium. During this phase, the embryo had a nose rostral to the eyes and dorsal to the mouth, but no speciesspecific characteristics. Only at 40 days did it show external characteristics that were specific to the species, such as a nasal diverticulum. The larynx and pharynx were observed at 26 days of gestation. Additionally, at 26 days, the formation of the epiglottal protrusions was noted, and as embryonic development advanced, cartilage formed, while over the larynx, a non-uniform epithelial lining was observed. At day 30 of gestation, the thyroid and cricoid cartilage were seen, and the formation of the epiglottis was clear. At 45 days, the larynx was completely formed, and the thyroid, cricoid, and cricoarytenoid muscle were identified. Lung tissue was observed in embryos from 24 to 49 days, and then a pseudoglandular transitional phase started between days 50 and 60. At this time, light bronchi and terminal bronchioles were observed and became wider as the lung tissue became more vascularized. Between days 90 and 105, the primary and secondary bronchi were tubular structures composed of columnar epithelium layers. Blood capillaries were observed in the lung. Structures similar to alveoli were not seen. This work contributes to advance knowledge regarding the organogenesis of the cardiorespiratory apparatus in horses.

Aims: Angiogenesis, as measured by degree of micro vessel density, has been associated with tumor progression in many tumor types, but does not always correlate with clinical outcome. Aggressive tumor cells were shown to form blood-conducting tubes not lined by endothelial cells, and this phenomenon was termed vasculogenic mimicry. Merkel cell carcinoma is a very aggressive but rare form of skin cancer, of neuroendocrine origin and with increasing incidence. We investigated the presence of vasculogenic mimicry in Merkel cell carcinoma in the Groene Hart Hospital, The Netherlands between 1990-2012.
Methods: Tumor tissues of all patients diagnosed with primary Merkel cell carcinoma in the period 1990-2012 in the Groene Hart Ziekenhuis were assessed on the presence of vasculogenic mimicry.
Results: We found vasculogenic mimicry in 11 (100%) out of the eleven patients primary diagnosed with Merkel cell carcinoma.
Conclusions: Vasculogenic mimicry is present in all Merkel cell carcinoma we found in our database and appears to be comparable to vasculogenic mimicry described in other tumors. Further investigation to vasculogenic mimicry can probably help us in finding a better understanding of the behaviour of Merkel cell carcinoma consequently a better treatment.

Background: Necromys lasiurus belongs to a group that includes New World rats and mice. The few studies concerning N. lasiurus consider this species to be a good experimental model because they adapt easily and because maintenance in captivity is low-cost. Moreover, Cricetidae are epidemiologically important as vectors of various diseases. The aim of the present study was to describe the macroscopic and microscopic features of embryonic and fetal development in this species.
Methods: Totally, 8 embryos and 12 fetuses were used and allocated in 6 groups. Gestational age was determined by the crown-rump length (CR) and weight. After the gross descriptions, samples were processed for light microscopy.
Results: The groups differed both macroscopically (due the characteristics related to the cervical curve, elongation of limbs and appearance of digits, closing of the auditory canal, blood vessels, elongation of the cranium, appearance of eyelids, skin thickness and coloration) and microscopically (the development of structures that constitute the facial region - mandibular, maxillary and nasal prominences). The structures preceding the appearance of the pituitary, lung, heart, brain cavity, fourth ventricle, liver development, the oral cavity, and layers that make up the cornea, retina, pigmented layer of the retina, and the lens were observed. Ossification of some regions was also observed.
Conclusion: The results showed that embryonic stage is present until day 15 of gestation. After this, during the fetal life the individuals showed a quickly development and maturation of the internal organs. These morphological results in regard to the development of N. lasiurus, can be used as a standard for interpretation of experiments that use this species as a model in science, including too compared with pathological results in disturbed gestations that can affect the normal development.

The current investigation was carried out on the seminal glands of six apparently healthy mature male Buffalo bulls and six immature. The specimens were collected and examined anatomically and histologically after being fixed in 10% buffered neutral formalin. The specimens were subjected to processing till paraffin sections were obtained and stained. The anatomical and histological findings of the seminal glands are varying with age. Anatomically, the immature seminal gland was small sized, flaccid in texture, white in color and measured about 0.80-0.95 gm in weight, 1.95-2.50 cm in length, 1.00-1.15 cm in width and about 0.46-0.60 cm in thickness. Meanwhile, in mature one became larger in size, firm in texture, pale yellow in color, multi-lobulated where had a very large lobules on its outer surface giving, cluster of grapes liked appearance. It measured about 7-8 gm in weight, 5-6 cm in length, 2-2.5 cm in width and about .80-1.3 cm in thickness. Microscopically, the seminal gland was observed consisting of a stroma of connective tissue and a parenchyma of differentiating and undifferentiating acini in immature animal. Meanwhile, in mature one, the parenchyma was consisted of secretory end pieces and well-developed duct system. With advancement of age, the thickness of the capsule and trabeculae increased, also the number of secretory end pieces per unite area increased and the amount of inter-glandular connective tissue stroma reduced.

The present investigation was carried out on the papillary muscles of ten healthy mature dromedary camels. Anatomically, the papillary muscles are muscular projections from the walls of the right and left ventricles into their cavities. They are processing many nipples like processes. The apex of each muscle process is attached to cord-like tendons; chordae tendineae. The latter, are string-like in appearance and are sometimes referred to as "heart strings" that linking the papillary muscles to the tricuspid valve in the right ventricle and the mitral valve in the left ventricle. These cords divided, in turn, into sub branches before attaching to the apex, body and base of the cusp, , preventing eversion of the valve leaflets into the atria during the ventricular contraction. So histologically, there are great invasions of the chordae tendineae to inside the papillary muscles. These chordae tendineae are observed highly branched looked like the tree roots and the finger like projections in between the cardiac muscle fibers within the papillary muscles. Histologically, the papillary muscle is consisting of two major layers; the central myocardium and the peripheral endocardium which act as a capsule. The myocardium has two bundles; the contractile cardiomyocytes bundles and the purkinje cardiomyocytes bundles. The papillary muscles are completely covered externally by a single layer of simple squamous epithelium; endothelium that is reflected from the ventricular endothelium. The latter, is supported by a subendothelial loose connective tissue that is mainly composed of collagen and elastic fibers.

The ovary is an endocrine and exocrine gland that plays primary role in female development and reproductive activities. The proper function of the ovary is influenced by other endocrine glands like the thyroid gland, which is one of the most important endocrine glands of the body that affects many cells all over it .This work is designed to focus on the histological and histochemical changes in adult female albino rat`s ovary that happened due to thyroid gland disorders. Forty five adult female albino rats were used in this study. The rats were isolated from male rat for a month before starting the experiment then they are classified into three groups: control group, taken 0.5 ml physiologic saline orally for three months, hypothyroid group, they were taken carbimazol at a dose of 12 mg / kg B.wt. orally for 3 months, hyperthyroid group, they were taken eltroxin at a dose of 100-ug/ kg. B.wt.. Blood samples were taken for assay of serum T3 and T4. Ovaries were fixed in 10% formol saline and paraffin sections were prepared and stained by different stains: Heamatoxylin and Eosin, Periodic acid Schiff`s reaction, Methyl green pyronine and Masson `s trichrome .The result of the control rats showed the well-known histological pictures and histochemical reactions. The hypothyroid group showed an increased ovarian activity as an increase in the surface epithelial cells, excessive amount of collagen fibers, an increase in the amount of CHO materials and in DNA and RNA content. Regarding the hyperthyroid group there was degenerative changes in the ovarian follicles, decrease amount of collagen fibers and decrease in the amount of CHO materials in the ovarian follicles. The association between ovarian diseases and thyroid gland disorders deserves further attention as normal reproductive function needs approximately normal thyroid secretion.

This is a case of fetal myopericytoma investigated by prenatal ultrasound and confirmed by autopsy and histopathological examination after termination of pregnancy. On antenatal ultrasonography, the fetus of 20 weeks gestation had a single large multicystic neck mass with enhanced Doppler flow. Parents chose to terminate the pregnancy. On autopsy the neck mass was found to be a tumor with numerous vessels with no other associated malformations. Histopathological examination with immunohistochemistry revealed the tumor to bear the characteristics of benign myopericytoma. This is probably the earliest gestation at which fetal myopericytoma has been reported.

The present investigation was performed to clarify the histological features of the left ventricles in the heart of the mature dromedary camel. This investigation was carried out on the left ventricles of six healthy mature camels. Microscopically, the left ventricles is consisted of three major layers or tunics; the internal endocardium, the middle myocardium, and the external epicardium. The endocardium is consisted of three layers; the endothelial layer of simple squamous epithelium, sub-endothelial layer of loose connective tissue and the sub-endocardial layer that connecting the endocardium with the myocardium and housing bundles of the purkinje cardiomyocytes; purkinje fibers. The myocardium, is the middle layer of the ventricular wall, is sandwiched between an outer epicardium, that covers the ventricular wall, and an inner endocardium, that lines the chamber, containing two bundles of cardiac fibers; the working cardiac myocytes (myocardiocytes) and the purkinje bundles. The epicardium is the outer most layer of the ventricular wall. This layer is a relatively thin in comparison with the myocardium and is consisted of a sub-epicardial layer of loose connective tissue which housing many blood vessels, lymph vessels, nerves and adipocytes and mesothelium of simple squamous epithelium.

Introduction: E-cadherin is an intercellular adhesion molecule, whose loss of expression may facilitate the process of cancer invasion and metastasis. Although the expression of E-cadherin has been widely studied in primary breast cancers, little is known about its expression at the corresponding metastatic lymph node. Here we comparatively studied their E-cadherin expression patterns and related them to the pathological data of breast cancer patients.
Methods: Only lymph nodes which were pathologically identified as metastases were included in this study to pair up the primary tumors. The quantitative real-time PCR (Q-RT-PCR) technique was used to assess the Ecadherin RNA expression levels in invasive ductal breast cancer subjects. E-cadherin gene copies were normalized using beta-actin gene copies. ER, PR, cerbB2 expressions in the primary tumor were routinely examined by immunohistochemistry method. Tumor characteristics and number of metastatic lymph nodes were gathered from the pathology reports.
Results: We tried to explore the relationship between E-cadherin expression in 21 primary tumors and their corresponding metastatic lymph nodes. However, the Q-RT-PCR data shows that an aberrant expression exists in both primary tumors and the corresponding lymph nodes (p=0.115), in which metastatic lymph nodes showed slight higher gene copies comparing to primary sites (77.77 ± 94.74vs43.35 ± 40.03, respectively). It is noteworthy that nodal E-cadherin expression was closely but negatively correlated with tumor size (p<0.01, r= -0.775) and number of meta sized lymph nodes (p<0.05, r=- 0.519), as tumor size and number of metastasized lymph nodes were already clinically proven to be important prognostic factors. There was no correlation between ER, PR, cerbB2 status in primary tumors and the nodal E-cadherin expression (p>0.05).
Conclusions: These study shows that E-cadherin expression is aberrant in invasive ductal cancers and their corresponding metastatic lymph nodes. E-cadherin expression in the metastasized lymph node is closely related to tumor size and number of metastasized lymph nodes.

Background: To date it is proved that Alzheimer’s disease (AD) is characterized by a multifactorial etiology which comprises mitochondrial dysfunction, energy depletion, inflammation, and oxidative stress associated with glutathione depletion. All these factors are known to be impacted by beta amyloid protein (Aβ), which is responsible for the activation of amyloidogenic cascade. In the present work a rat intracerebroventricular Aβ(1-40) infusion model of early AD was employed to investigate the effects of Ibuprofen-Glutathione (IBU-GSH) conjugate on morphological modifications, Aβ plaque formation, apoptosis, learning, and memory performance.
Methods: Water maze test was used to evaluate drug administration effects on spatial reference memory, immunohistochemistry was carried out to determine Aβ 1-40, iNOS and caspase-3 expression; semithin sections and ultrastructural analyses, by means of light and transmission electron microscopy, respectively, were realized to evaluate samples morphology; TUNEL analysis to identify apoptotic cells.
Results and Conclusion: Results showed that in the Aβ+IBU-GSH conjugate treated group, long-term memory consolidation at day 12 was improved, while learning appeared slower respect to control. In Aβ-infused rats, a higher number of Aβ plaques, disorganized pyramidal pyknotic cells, apoptotic cells containing fragmented or swollen mitochondria, dilated blood vessels, and a low number of oligodendrocytes along with the high expression of inducible Nitric Oxide Synthase (iNOS) and caspase-3 were put in evidence. The inflammatory state seemed to be reversed by IBU-GSH treatment, as evidenced by a lower number of Aβ plaques and pyknotic cells, and reorganized neurons containing normal mitochondria; despite this, persistent dilated blood vessels, decreased iNOS expression, lower percentage of apoptosis, and weak caspase-3 levels were observed. Thus mitochondria involvement in the AD inflammatory state is here strongly suggested and neuro-protective and anti-apoptotic IBU-GSH conjugate effect could be useful to reduce the AD inflammatory state.

Introduction: Chronic inflammation and duodenal gastric metaplasia (DGM) increase with the presence of Helicobacter pylori (Hp). DGM is considered the earliest change in the development of duodenal ulcer in children with Hp gastritis. Until now, histopathological duodenal changes in children with Hp associated gastritis had not been studied in Mexico, where there is a high gastric Hp prevalence.
Objective: This study aims to describe the histopathological findings of duodenal biopsy in a Mexican children population with Hp-associated gastritis.
Materials and Methods: This cross-sectional, retrospective and analytical study examined, using light microscopy, the gastric and duodenal biopsies from a consecutive series of cases of children with and without Hp gastritis, received from 2000 to 2007. In the duodenal biopsy, active or non-active chronic duodenitis and DGM were observed. The DGM was highlighted with alcian blue/PAS stain.
Results: 306 patients with a histopathological diagnosis of chronic gastritis, 95 with Hp and 211 without Hp, are included in this study. The frequency of chronic duodenitis in patients with chronic gastritis by Hp is 100%. We found the highest gastric Hp frequency (p<0.001) in the group of oldest patients (11 to 16 years). The frequency of DGM was higher (15.7% vs 7.5%) when there was gastric Hp (p<0.019). It was demonstrated that there is no correlation (p>0.05) between Hp-associated chronic gastritis and the following: alteration of villus height/crypt depth ratios, damage to surface enterocytes, loss of brush border, and duodenal ulcer.
Conclusions: In the Mexican children population with and without Hp chronic gastritis studied, chronic duodenitis is a very common histopathological finding. The DGM is related to the presence and density of gastric Hp. To confirm DGM, an ancillary method could be used in the endoscopic duodenal biopsy.

Introduction: The submandibular gland is the largest salivary glands that secrete saliva. Starvation or food deprivation was found to influence all body metabolic activities that are reflected on the structure of many organs including salivary glands.
Aim of the work: This work is aimed to study the possible histological, histochemical and ultrastructural changes of submandibular gland associated with long-term (7 and 14 days) food deprivation.
Materials and Methods: Twenty young male cats were divided into 2 main groups. Group I: served as control, received solid diet for 7 and 14 days. Group II: animals were starved for 7 and 14 days. The cats were sacrificed and specimens from submandibular gland were taken for light and electron microscopic examination.
Results: Light microscopic examination of starved cats revealed distension of secretory units with secretory granules, vacuolated cytoplasm and pyknotic nuclei. The changes were augmented with prolongation of periods of starvation for 14 days. Histochemically, starvation leads to a decrease or alteration in metachromatic staining of secretory granules that tends to be unstained with prolonged period of starvation for 14 days. Ultrastructurally, the secretory granules of acinar and demilunar cells appeared with more electron dense with degeneration of rough endoplasmic reticulum and mitochondria as well as significant accumulation of lipid droplets within these cells and in striated ducts. Conclusion: Results obtained in this study demonstrated that food deprivation for long periods induced marked histological, histochemical and ultrastructural changes in the submandibular gland as well as altered saliva composition with a concomitant decrease in acid and neutral mucosubstances.

In major depression, in both midbrain and hippocampus a hypoactivity of monoamines (serotonin, noradrenalin, dopamine) and a hypoactivity of presynaptic inhibitory neurotransmitters (GABA, glutamate) occurs. Serotonin hypoactivity, which is partly explained by polymorphisms of the serotonin transporter gene, could be as well due to an enhanced presynaptic inhibition carried out by glutaminergic neurons via m5Glu receptors. Noradrenalin hypoactivity is also due to an enhanced presynaptic inhibition exerted, via GABAB receptors, by GABAergic neurons. We derived neural networks from direct and reciprocal correlations between neurotransmitters. The neural networks presented here suggest a multimodal antidepressant pharmacotherapy by combining enhancing and antagonistic antidepressant drugs, for example noradrenalin reuptake inhibitors and GABAB antagonists.

Kaposi’s sarcoma is a frequently seen AIDS-related malignant neoplasm in the head and neck region, especially in the oral cavity, but is rarely described in the HIV-negative and immunocompetent individual. We present the iatrogenic Kaposi’s sarcoma affecting soft palate which developed in a 53-year-old male and discuss their histological features and differential diagnosis.

Intraparenchymal isolated bile ductules (IIBDs) are occasionally recognizable in liver specimens, but their characteristics remain poorly understood. Therefore, we (2 pathologists) attempted to identify IIBDs in 81 hematoxylin and eosin-stained needle biopsy specimens of the liver, and examined the interobserver variation and their clinicopathologic features. Aberrant cytokeratin 7 (CK7) expressions of hepatocytes, known to represent hepatic progenitor cell (HPC) activation, were also evaluated. In each specimen, the mean number of IIBDs counted by us was divided by the number of portal areas, which was defined as the IIBD score. Both pathologists detected IIBDs in 53 specimens (65.4%), indicating that they are not rare. Observed agreement was obtained in 81.5%, and the kappa statistic indicated moderate agreement (kappa: 0.515). Higher IIBD score was closely associated with a higher degree of hepatocytic CK7 expression in all areas (P=0.012), periportal areas (P=0.007), and pericentrilobular vein (CV) areas (P=0.032), but not with age, gender, increased serum levels of liver dysfunction tests, or hepatic steatosis. Ductular reaction was also associated with hepatocytic CK7 expression in all areas (P=0.004), periportal areas (P=0.024), and peri-CV areas (P=0.031). However, there was not a relevant relationship between higher IIBD score and a severe degree of ductular reaction. In non-alcoholic steatohepatitis (NASH) cases, significant IIBD score was correlated with grading score (P=0.043), but not with fibrosis staging score. In viral hepatitis cases, it was not associated with grading or staging score. These results suggested that the development of IIBD can highlight HPC activation, but might be independent of periportal HPCs, also known as “periportal niches”. The presence of IIBDs would be due in part to a hepatic necro-inflammatory state in some conditions, such as NASH.