Morphogenesis of the ostrich (Struthio camelus) trachea and lung in different embryonic and fetal stages.

The ostrich (Struthio camelus) is an important wild species highlighted in national and international livestock industry. This research was conducted to analyze the development of the ostrich respiratory system during fetal and embryonic stages. A total of 50 fertile ostrich eggs were collected from commercial farms and then incubated at 36.00 - 37.00 ˚C and 25.00 ± 2.00% humidity for 40 days. Sections were taken on days 13, 22, 26, 30, 36, and 42 of incubation from the lung and the cranial, middle, and caudal parts of the neck after decapitation of ostrich embryos and blood drainage. After fixation, processing, blocking, and sectioning, all samples were stained by Hematoxylin and Eosin, Alcian Blue (AB), Van Gieson, and Periodic acid-Schiff (PAS) techniques. It was concluded that the trachea in the 13-day-old embryo and goblet cells (PAS-positive and AB-positive) had incomplete rings of hyaline cartilage and differentiation of mesenchymal to the loose connective tissue. The bronchial stage of the lung was observed in the 22-day-old embryo, pseudoglandular stage in the 26-day-old embryo, and parabrachial and air capillary stage in the 30-day-old embryo. The information obtained from this study will be useful for diagnosing pathologies affecting this vital system and results in improving industrial breeding management.

Transplantation of human adipose-derived stem cells overexpressing LIF/IFN-ß promotes recovery in experimental autoimmune encephalomyelitis (EAE).

Multiple Sclerosis (MS) is the most common demyelinating disease with inflammatory demyelination in the central nerve system. Besides the defect in the myelin repair process, the balance change in inflammatory and anti- inflammatory cytokines is one of the most significant factors in MS pathogenesis. This study aimed at evaluating the effects of co-overexpressing beta interferon (IFN-ß) and Leukemia inhibitory factor (LIF) in human adipose-derived stem cells (IFN-ß/LIF-hADSCs) on the experimental autoimmune encephalomyelitis (EAE). 12 days after the induction of EAE on female mice C57Bl/6 with MOG35-55 and the emergence of primary clinical signs, the IFN-ß/LIF-hADSCs were injected into the mice tail vein of the EAE mice. The mice were sacrificed after 32 days and the spinal cords of the experimental groups were dissected out for the histopathologic and real-time RT-PCR studies. Here, we showed that the clinical scores and infiltration of mononuclear cells of treated mice with IFN-ß/LIF-hADSCs were decreased significantly. Demyelination and the number of Olig2+ and MBP+ cells were significantly increased in the test (IFN-ß/LIF-hADSCs) group. The findings revealed that the pattern of inflammatory and anti- inflammatory cytokines gene expression in the IFN-ß/LIF-hADSCs group was reversed compared to the control group. Overexpression of LIF as a neurotrophic and IFN-ß as an anti-inflammatory cytokine in hADSCs increases the immunomodulatory effect of hADSCs reduces the extent of demyelination, improves the number of Olig2+ cells, and also increases the amount of MBP protein which can increase the production of myelin in EAE model. This, besides hADSCs capacity for proliferation and differentiation, might enhance the treatment efficacy and provide a promising candidate for stem cell-based gene therapy of MS therapy in the future.

Histological and stereological approaches for detection of tissues and fraud in some meat products.

Meat and meat products are highly important sources of protein in the diet. Nowadays, the consumption of meat and meat products has increased owing to modern manufacturing techniques. Due to the economic value of meat, the use of unauthorized tissue is possible in meat products. In some cases, there is fraud in the percentage of meat in meat products to reduce prices. In this study, 34 samples of minced meat, hamburger and sausage were randomly collected from the markets in the northeast of Iran. Then, sections were stained using Hematoxylin and Eosin (H & E), Verhoeff-van-Gieson, Masson's trichrome and periodic acid-Schiff-Alcian blue stains. In this regard, for the first time, the efficacy of stereological technique to determine the percentage of meat listed in sausages and the possible existence of fraud was evaluated. The results showed that, due to the presence of some unusual tissues, histological technique could determine different tissues in meat products. The stereological results of control samples showed a very slight difference; whereas, the results for the samples collected from the city stores showed a distinctive difference regarding the percentage of meat compared to the percentage of label. Skeletal and smooth muscles, blood vessels, nerve, gizzard, adipose tissue, glandular tissue, cartilage, bone, tendon, skin, lymphatic tissues and plant materials were observed. It was confirmed that stereology was a reliable method to determine and confirm the percentage of meat used in meat products.

Ultrastructure characteristics of primordial germ cells in stage X of pheasant (Phasianus colchicus) embryo.

Stage X is one of the formation stages in birds at which the blastoderm area is distinguished by two areas of area pellucida being responsible for formation of embryonic tissues and primordial germ cells, and area opaca forming the extra-embryonic tissues. Primordial germ cells are multi-potent stem cells giving rise to spermatogonia or oogonia. The present study was carried out to describe the characteristics of primordial germ cells in stage X of pheasants' embryo using a transmission electron microscope. The blastoderm was dissected out from embryos which were already incubated for 12 hr. Toluidine blue was used for staining semi-thin sections; lead citrate and uranyl acetate were also used to stain ultra-thin sections. Images of primordial germ cells elucidated that the nucleus was situated eccentrically and had a compact spherical structure. Moreover, the nucleolus appeared elongated and was located eccentrically. The cytoplasm was composed of yolk granules and glycogen particles. Mitochondria were observed as round structures in the cytoplasm. The most important finding was that the primordial germ cells contained yolk granules, mitochondria and small amount of glycogen at this stage.

Application of histological method for detection of unauthorized tissues in meat sausage.

Nowadays, the consumption of meat and meat products has been increased with modern manufacturing techniques. Due to the economic value, the likelihood of using unauthorized tissue is possible in meat products. The aim of this study was to apply morphological methods for detection of unauthorized tissues in meat sausage. In this study, a total number of 20 samples of different types of sausages were randomly collected from markets, in north-east of Iran. Each sample was divided into three equal parts and three paraffin-embedded blocks were prepared from each part (180 blocks). Then the sections were stained using Hematoxylin and Eosin, Masson's trichrome, Periodic acid- Schiff/Alcian blue and Verhoeffe/Van Gieson. A total number of 720 slides were observed using a light microscope. This research showed the use of unauthorized tissues in the sausages which was detected by histological methods. We observed authorized tissues like skeletal muscle fiber (100%), fat tissue (100%) and plant material (97.70%). A wide range of unauthorized tissues were detected including dense connective tissue (6.66%), cartilage (28.30%), bone (8.30%), skin (51.60%), smooth muscle (1.66%) and blood vessels (11.66%). The results of this study confirmed the use of unauthorized tissue in meat sausages in Iran and concluded that the histological methods especially Masson's trichrome staining are a practical technique for routine assessment of authenticity and quality of sausage to protect the consumers from adulteration.

Morphological development of testes in ostrich (Struthio camelus) embryo.

Although the histological structure of ostrich testis has been studied, very little information is currently available on the embryonic development of this organ. The aim of this study was to determine the sequence of the histological changes in diverse components of the testis in ostrich embryo from embryonic day (E) 20 to E42. The main findings were categorized into four histological features, i.e., development of sex cords, interstitial tissue and rete ducts, and the appearance of defective septa. While the lumen of sex cords, tunica albuginea, capsular rete ducts and Leydig cell precursors appeared at E26, the filum-shaped defective septa were visible at E36. The emersion of the lumen in the primary sex cords and formation of capsular rete ducts in the ostrich embryo is considerably different from that in other birds. However, tunica albuginea and Leydig cell precursors appeared in a similar pattern to those of other birds. An interesting observation was that the primordial germ cell (PGC)-like cells were completely distinct, while the capsular rete ducts were formed by trapping of some Sertoli cell aggregations in the tunica albuginea. This suggests that similar to the primary sex cords, the capsular rete ducts may originate from the Sertoli cell aggregations which had corralled some PGCs. Stereological estimations in the ostrich embryo testis showed the major proportion of testis is occupied by the seminiferous tubules, which is unlike the fowl embryo testis.

Microanatomical study of testis in juvenile ostrich (Struthio camelus).

The majority of investigations on the testis, as the main organ of male reproductive system, have been performed in mammalian species, with few studies on bird species. Thus, the structure of the ostrich testis remains largely unknown. The aim of this study was to investigate the microanatomical characteristics of the testis in five juvenile ostriches. A stereological study was performed according to the Delesse principle. The mean volume fraction of the seminiferous tubules was 0.569, and the mean volume of the seminiferous tubules in an average testis was 1.04 cm(3). The Paraffin-embedded sections were stained with hematoxylin and eosin, Masson's trichrome, Alcian blue, and periodic acid-Schiff stains. Histological studies revealed that the spermatogonial stem cells and Sertoli cells were localized inside the seminiferous tubules, close to the basement membrane. Inside the tubules a few meiotic cells up to the spermatozoa stage were located in a centripetal manner. Outside the tubules, one to three layers of euchromatic peritubular myoid cells were present, surrounded by loose interstitial connective tissue. A thick tunica albuginea contained many myoid cells and some rete ducts, with the latter extending from the hilus to the free surface of the testis. Straight seminiferous tubules were distributed in the lateral surfaces and hilar portions of the capsule but were rare in the free surface. These capsular rete ducts may participate in testicular fluid transit from the distal tubules through the capsule.