The liver performs many functions, which support metabolism, immunity, digestion, detoxification, vitamin storage, and so on. The liver is the storage organ for fat-soluble vitamins, iron and copper. Six adult healthy guinea pigs of 16-32 weeks of age (Irrespective of sex) were procured from the Department of Laboratory Animal Medicine, TANUVAS as per ethical committee approval. Animals were dissected as per CPCSEA norms and liver pieces were utilized for scanning electron microscopy (SEM) and transmission electron microscopy (TEM) study. The study was performed to document the ultrastructural details of liver of guinea pigs by SEM and TEM. By SEM, the liver parenchyma appeared as lobular with anastomosed one cell thick hepatic cell plates, which appeared as continuous sheets with small to large holes representing sinusoids. The sinusoidal lumen was lined by two types of cells namely endothelial cells and Kupffer cells. Endothelial cells had numerous large and small cytoplasmic fenestrations. Presence of Kupffer cells along with Ito cells were observed in the sinusoids. By TEM, hepatocytes had angular shape with sinusoidal face and bile canalicular face. Hepatocytes had oval nucleus with peripheral heterochromatin and central electron lucent granules and a prominent nucleolus. Bile canaliculi were formed by two adjacent hepatocytes. Fenestrated endothelial cells with flat and elongated shape were found to be in the formation of hepatic sinusoidal wall. A narrow space of Disse was found between the sinusoidal endothelium and hepatocytes. Kupffer cells and pit cells were found within the sinusoidal lumen. Ito cells were found in the space of Disse. RESEARCH HIGHLIGHTS: By scanning electron microscopy, the liver parenchyma appeared as lobular with anastomosed one cell thick hepatic cell plates, which appeared as continuous sheets with small to large holes representing sinusoids. By transmission electron microscopy, hepatocytes had angular shape with sinusoidal face and bile canalicular face. Hepatocytes had oval nucleus with peripheral heterochromatin and central electron lucent granules and a prominent nucleolus.
Copper , Endothelial Cells , Animals , Electrons , Guinea Pigs , Heterochromatin , Iron , Liver/ultrastructure , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Vitamins
Health impact assessment (HIA) practice has expanded across the world, since it was established more than two decades ago. This paper presents a snapshot of current global HIA practice based on the findings of an online questionnaire survey. HIA practitioners from all world regions were invited to participate. A total of 122 HIA practitioners from 29 countries completed the survey, following a broad international outreach effort. The large variety in the types of HIAs conducted, and the application of HIA in various fields reported by respondents, demonstrates that HIA practice has evolved over the past two decades. Although differences in the use of HIA were reported across world regions, an overall increasing trend in global HIA practice can be observed. In order to sustain this upward trend, efforts are needed to address the main barriers in the utilisation of HIA. The establishment of new national and international HIA teaching and training offerings seems to be an obvious strategy to pursue along with the strengthening of policies and legal frameworks that specify the circumstances, under which HIA is required, and to what extent.
Health Impact Assessment , Health Policy , Policy Making , Humans , Policy , Surveys and Questionnaires
The present study aimed to document the seasonal variations in the testicular morphology of the adult guinea fowl (Numida meleagris) under tropical savannah climate of India. The study was conducted in 24 adult healthy guinea cocks. The testes were ovoid in shape throughout the year. The consistency of the testes was moderately firm with great resilience and creamy white in colour during summer and monsoon-I whereas soft in consistency and dull white to yellowish tinge in colour during monsoon-II and winter seasons. The testicular weight, length, width, thickness, volume and circumference were higher during summer and monsoon I than the winter and monsoon II seasons. The mean body weight of the birds did not show significant difference among the seasons. The testicular weight, length, width, thickness, volume and circumference were higher during the summer and monsoon I than the winter and least during monsoon II in the current study. The gonadosomatic index (GSI) and paired testicular weight were high and showed no significant difference during the summer and monsoon-I whereas during winter and monsoon-II, the values were low and showed significant difference between them. The diameter of the seminiferous tubules and its lumen, the diameter of the sustentacular cells (Sertoli cells) were much higher during summer and Monsoon I than winter and monsoon II seasons. The percentage area of interstitial cells and the thickness of the testicular capsule appeared less during the summer and monsoon I seasons. The decreased size of seminiferous tubules, increased amount of cellular debris in the tubular lumen, degenerating germ cells and collapse of seminiferous tubules observed during monsoon II and winter in the present study.
El presente estudio tuvo como objetivo documentar las variaciones estacionales en la morfología testicular de la gallina de Guinea (Numida meleagris) en el clima de la sabana tropical de la India. El estudio se realizó en 24 gallos adultos sanos de Guinea. Los testículos fueron ovoidedurante todo el año. La consistencia de los testículos fue moderadamente firme con gran elasticidad y color blanco cremoso durante el verano y durante el Monzón I, mientras que de consistencia blanda y color blanco pálido a amarillento durante el Monzón II y las temporadas de invierno. El peso testicular, la longitud, el ancho, el grosor, el volumen y la circunferencia fueron más altos durante el verano y el Monzón I en comparación con las temporadas de invierno y Monzón II. El peso corporal medio de las aves no mostró una diferencia significativa entre las estaciones. El peso testicular, la longitud, el ancho, el grosor, el volumen y la circunferencia fueron más altos durante el verano y el Monzón I en comparación con el invierno y menos durante el Monzón II. El índice gonadosomático (GSI) y el peso testicular apareado fue alto y no mostraron diferencias significativas durante el verano y el Monzón I, mientras que durante el invierno y el Monzón II, los valores fueron bajos y mostraron diferencias significativas entre ellos. El diámetro de los túbulos seminíferos y su luz, el diámetro de las células sustentaculares (células de Sertoli) fue mucho mayor durante el verano y el Monzón I que en las estaciones de invierno y el Monzón II. El área de porcentaje de células intersticiales y el grosor de la cápsula testicular aparecieron menos durante las temporadas de verano y Monzón I. Se identificaron en el presente estudio disminución del tamaño de los túbulos seminíferos, el aumento de la cantidad de restos celulares en la luz tubular, la degeneración de las células germinales y el colapso de los túbulos seminíferos observados durante el Monzón II y el invierno.
Animals , Male , Seasons , Testis/anatomy & histology , Galliformes/anatomy & histology
SUMMARY: The morphology of the interstitial tissue of sexually active and resting testis of the guinea fowl were studied. Six adult health birds of active and resting phases of reproductive cycle were used for this study. The interstitial tissue consisted of loose connective tissue, interstitial cells (Leydig cells), few connective cells, blood vessels and adrenergic nerve fibres in the present study in both active and resting testes. The interstitial tissue was compact in sexually active testis whereas, the volume of the tissue was found to be increased in resting testis. The loose connective tissue of the interstitial tissue composed of mainly of collagen fibres and few reticular fibres whereas elastic fibres were absent in both groups studied. The interstitial cells appeared in clusters of a few cells and were relatively less in the active testis than the resting testis. The interstitial cells were pale staining or polygonal cells with euchromatic nuclei with few large lipid droplets in the active testis whereas the cells were flat and highly heterochromatic with numerous small lipid droplets in resting testis. Few macrophages were found only in resting testis. Interstitial cells showed negative reaction to alkaline, acid phosphatases and PAS in both groups studied but positive for lipids. The interstitial tissue was well vascularised with centrally located blood vessels in the active testis whereas the blood vessels were small and inconspicuous in the resting testis. The lymphatic vessels were not identified in both groups studied.
RESUMEN: Se estudió la morfología del tejido conectivo intersticial en testículos sexualmente activos y en reposo de la gallina de Guinea (Numida meleagris). Se utilizaron seis gallinas de Guinea machos adultos sanos, en fase activa y de reposo del ciclo reproductivo. El tejido conectivo intersticial estaba formado por tejido conectivo laxo, células endocrinas intersticiales, pocas células conectivas, vasos sanguíneos y fibras nerviosas adrenérgicas, tanto en testículos activos como en reposo. El espacio intertubular en los testículos sexualmente activos era menor en comparación a los del testículos en reposo. El tejido conectivo laxo estaba compuesto principalmente de fibras colágenas y en menor cantidad de fibras reticulares. Las fibras elásticas estaban ausentes en ambos grupos. Las células endocrinas intersticiales se organizaban en racimos de pocas células y se observaban con menor frecuencia en los testículos sexualmente activos. Las células endocrinas intersticiales de los testículos activos presentaban forma poligonal, citoplasma levemente eosinofílico con algunas gotas lipídicas de gran tamaño en su interior y nucleos redondos con cromatina laxa. Las células intersticiales de los testículos en reposo eran planas y altamente heterocromáticas, con numerosas gotas lipídicas pequeñas en su citoplasma. Las células intersticiales mostraron una reacción negativa a las fosfatasas ácidas, alcalinas y PAS en ambos grupos, Sin embargo presentaron reacción positivas para los lípidos. El tejido conectivo intersticial estaba bien vascularizado con vasos sanguíneos situados centralmente en el testículo activo y vasos sanguíneos pequeños y discretos en el testículo en reposo. Los vasos linfáticos no fueron identificados en los dos grupos estudiados.Los macrófagos fueron observados solo en los testículos en reposo, aunque en escasa cantidad.
Animals , Male , Connective Tissue Cells/ultrastructure , Galliformes/anatomy & histology , Testis/cytology
The present study was aimed to study the light and electron microscopic studies of thymic Hassall's corpuscles was done in various age groups of Nandanam Chicken ranging from day-old to forty weeks. Hassall's corpuscles are special, unique structures present in thymic medulla and also in the cortex of all the age groups of Nandanam chicken (from hatch to forty weeks) in the present study. Size of the Hassall's corpuscles in the medulla is larger than the ones present in the cortical region of thymus. The Hassall's corpuscles are made up of structureless eosinophilic mass surrounded by concentrically arranged reticuloepithelial cells. Under electron microscope, the Hassall's corpuscles were composed of reticuloepithelial cells interconnected by many desmosomes. The epithelial cells had abundance of cytoplasmic fibrils and desmosomes with few mitochondria and ribosomes. The nucleus was oval or round which was slightly indented. The centre of the Hassall's corpuscles was appeared either solid or cystic. The cystic corpuscles had cell debris within the cyst lumen.
The tissue pieces of palatine tonsil were collected from different postnatal age groups of sheep from the Corporation Slaughter House, Perambur, Chennai. The palatine tonsil consisted of a surface epithelium, capsule, tonsillar lobes, crypts, crypt epithelium and tonsillar follicles. The surface epithelium over the palatine tonsil was made up of non-keratinized stratified squamous epithelium in all the postnatal age groups studied. The palatine tonsil was clearly demarcated from the surrounding structures by a distinct connective tissue capsule and one septa dividing the tonsil into two lobes. The surface epithelium was invaginated into the substance of the tonsil to form primary and secondary crypts in each lobe. The crypt epithelium covered the regions of lymphoid follicles became lymphoepithelium. The macrophages were also observed in the epithelium. In the areas of lymphoepithelium the basement membrane was interrupted since lymphocytic infiltration was heavy into the epithelium. Numerous secondary tonsillar follicles with germinal centers separated by interfollicular areas were observed in the palatine tonsil. The tonsillar follicles consisted of a mantle zone, which was heavily populated with small darkly stained lymphocytes. These mantle zones were always oriented towards the crypts. The tonsillar follicles of young sheep showed many medium and small sized lymphocytes, lymphoblasts and also reticulocytes. The reticular cells usually appeared larger than lymphocytes and had a more abundant and organized cytoplasm with vacuoles.
Fueron recolectadas piezas de tejido desde la tonsila palatina de ovejas con diferentes edades postnatales, desde la Corporación Slaughter House, Perambur, Chennai. La tonsila palatina consistía en un epitelio de superficie, cápsula, lóbulos de las tonsilas, criptas, epitelio de las criptas tonsilares y folículos. El epitelio superficial sobre la tonsila palatina estaba compuesto, en todos los grupos estudiados, de epitelio escamoso estratificado no-queratinizado. La tonsila palatina se delimitó claramente de las estructuras circundantes por un tejido conectivo capsular y un septo dividiendo la tonsila en dos lóbulos. El epitelio superficial se invaginó dentro de de la tonsila para formar criptas primarias y secundarias en cada lóbulo. El epitelio de las criptas cubrió las regiones de folículos linfoides transfomándose en linfoepitelo. También se observaron macrófagos en el epitelio. En las áreas de linfoepitelo la membrana basal estaba interrumpida por la infiltración linfocitaria y fue mayor en el epitelio. Fueron observados numerosos folículos tonsilares secundarios con centros germinales separados por áreas interfoliculares. Los folículos tonsilares consistían en una zona del manto que estaba densamente poblada con pequeños linfocitos intensamente teñidos. Estas zonas del manto se orientaron siempre hacia las criptas. Los folículos tonsilares de las ovejas jóvenes mostraron muchos linfocitos de tamaño medianos y pequeños, linfoblastos y también reticulocitos. Las células reticulares usualmente aparecían más grandes que los linfocitos y tenían un citoplasma más abundante y organizado con vacuolas.
Animals , Palatine Tonsil/ultrastructure , Sheep/anatomy & histology , Photomicrography
