Electrophoretic and immunocytochemical analysis of Hsp72 and Hsp73 expression in heat-stressed mouse testis and epididymis.

Objective: One of the most profound events in stressed cells is the synthesis of a highly conserved family of proteins, the 'heat shock proteins' (Hsp). The Hsp70 family is the most diverse, and includes constitutive as well as stress-inducible proteins with overlapping or unique functions in different cell compartments. Elucidation of Hsp70 expression during different stages of spermatogenesis and maturation of germ cells is of particular interest due to their high sensitivity to heat treatment.

Ultrastructural study of cat zona pellucida during oocyte maturation and fertilization.

The mammalian zona pellucida (ZP) is an extracellular glycoprotein structure formed around growing oocytes, ovulated eggs and preimplantation embryos. The specific functions of ZP are highly determined by its morphological structure. Studies on cat oocytes during maturation and after fertilization were undertaken, using routine transmission (TEM) and scanning electron microscopy (SEM).

Role of FGF1, FGF2 and FGF7 in the development of the pancreas from control and streptozotocin-treated hamsters.

Although progress has been made with respect to the growth and transcription factors implicated in pancreatic development, many questions remain unsolved. It has been established that during embryonic life, both endocrine and acinar cells are derived from pancreatic epithelial precursor cells. Growth factors control the proliferation of precursor cells and their ability to differentiate into mature cells, both in pre-natal and in early post-natal life.

Miltefosine decreases the cytotoxic effect of epirubicine and cyclophosphamide on mouse spermatogenic, thymic and bone marrow cells.

A new class of potent anticancer drugs, alkylphosphocholines has been recognized lately. Miltefosine (Hexadecylphosphochlorine, HPC) has been found to express select antineoplastic effect on human breast cancer skin metastases with simultaneous preservation of bone marrow proliferative activity and low clastogenicity. In the current study, we present data about the specific effect of two widely used cytostatics Cyclophosphamide (CP) and Epirubicine (ERb) applied separately or in combination with Miltefosine.

The effect of in vitro fibroblast growth factors on cell proliferation in pancreas from normal and streptozotocin-treated rats.

Fibroblast growth factors (FGFs) are potent mitogens for a wide variety of cells. In the present study we examined the potential morphogenic activities of the growth factors FGF1, FGF2 and FGF7, and cellular processes underlying morphogenesis, in pancreatic cells from streptozotocin diabetic newborn rats. The pancreases from control and diabetic newborn rats were microdissected and cultured in the presence of different doses of FGF1, 2 and 7 for 48 h.

Leukaemia inhibitory factor stimulates proliferation of prospermatogonial stem cells.

The effect of leukaemia inhibitory factor (LIF) on the proliferation of prospermatogonial stem cells was tested in vitro. Pieces of 3-day-old rat testis were cultured in the presence of a range of doses of LIF alone or in combination with 1 ng mL(-1) seminiferous growth factor (SGF). Stimulation of the proliferative activity of quiescent prospermatogonia was detected immunocytochemically with a cell proliferation kit.

Differential effects of prepubertal rat Sertoli cell secreted proteins on somatic testicular and nontesticular cells.

There is little information on the mitogenic and immunoregulatory activities of proteins, secreted by prepubertal Sertoli cells during the stage of meiosis initiation and before creation of the blood-testis barrier. We have previously demonstrated dose-dependent and age-related stimulation of BALB/c 3T3 fibroblasts and quiescent rat prespermatogonia (Kancheva et al., 1990) as well as inhibition of natural killer cell activity of mice, guinea pigs and human lymphocytes (Nikolova et al.

The perinuclear matrix as a structural element of the mouse sperm nucleus.

The mouse sperm nucleus, after the removal of protamines and DNA, consisted of a skeletal structure that conformed to the original nuclear shape. Sperm were extracted with 1% SDS, and the isolated nuclei, along with the enveloping perinuclear theca, were incubated in 25 mM dithiothreitol, and exposed to different reagents in an effort to displace the protamines, P1 and P2. Protamines, labeled with [3H]arginine, were displaced from the nucleus by CaCl2.

Species-specific effect of proteins secreted by cultured pre-pubertal rat Sertoli cells on natural killer cell activity.

The effect of proteins secreted by cultured pre-pubertal rat Sertoli cells (pSCP) on natural killer (NK) cell activity of rat, mice and guinea pig splenocytes and human peripheral blood lymphocytes was estimated. The results indicate that pSCP inhibited, in a dose-dependent manner, NK cell activity of mice, guinea pig and human lymphocytes but did not suppress lysis of YAC-1 target cells by rat NK cells. Species-specific differences in the effect of pSCP on NK cell activity probably result from differences in the binding of proteins within the effector cells.

Effect of orchiopexy on human testicular ultrastructure.

The effect of orchiopexy performed before puberty on the testicular ultrastructure in sexually mature infertile men have been levels, as well as an analysis of spermogram and karyotype was carried out. It was found an elevation of FSH and LH, while T levels were decreased. Disturbances in the ultrastructure of all testicular cell types-germ, Sertoli and Leydig cells are related with the smooth and rough endoplasmic reticulum and mitochondria as well.

Prepubertal rat Sertoli cells secrete a mitogenic factor(s) that stimulates germ and somatic cell proliferation.

Sertoli cells were isolated from prepubertal 6- and 12-day-old rats. The Sertoli cell-conditioned media (SCCM-6 and SCCM-12) can markedly stimulate the proliferation of somatic cells and quiescent rat prespermatogonia in a dose-dependent and an age-related manner. SCCM-12 stimulated cell proliferation of BALB/c 3T3 fibroblasts up to 7-fold over control values, but did not stimulate to the same degree the germ cell mitotic activity.

Ultrastructural alterations in mouse spermatogenic cells after treatment with anticancer drug biocarbazine.

Single doses of anticancer drug biocarbazine (BC)--DTIC synonym--were injected intraperitoneally at 50 and 200 mg/kg body weight to sexually mature BALB/c mice. Among other features previously reported (Martinova et al. 1989) BC causes ultrastructural alterations in spermatogonia and spermatocytes significantly expressed after administration of higher dose.

An immunocytochemical study of the proliferating cell nuclear matrix antigen p125/6.5 during rat spermatogenesis.

In previous studies of proliferating mammalian cells a p125/6.5 nuclear matrix antigen displaying a marked increase in mitotic cells has been identified. This antigen was investigated by immunocytochemistry of cryosections of testes at different stages of postnatal development: newborn, 20 days after birth and sexually mature rats.

Early effect of the anticancer drug biocarbazin (DTIC synonym) on mice spermatogenesis.

Biocarbazin (DTIC synonym) is an anticancer drug acting as a purine analogue, as an alkylating agent, as a SH-group blocker. Biocarbazin administration in doses 50 and 200 mg/kg of body weight to adult male BALB/c mice suppresses the process of spermatogenesis. Seminiferous tubule of the testis displayed dose-dependent histological alterations manifested with decrease of mitotically dividing cells and increase in the number of multinucleated spermatocytes and spermatids.

Testicular ultrastructure in infertile men.

The review shows typical ultrastructural alterations of germ, Sertoli, and Leydig cells in infertile men. Regardless of the cause of infertility, the disruption of the spermatogenic process usually occurs in the pachytene stage of meiotic prophase and in the stages of early spermatid maturation. The disturbances affect the cytoplasm more than the nucleus, and the synaptonemal complexes have shown significant stability even in the severely injured testes.

Histoautoradiographic studies of 3H-thymidine labelled Erysipelothrix rhusiopathiae introduced into albino mice.

S-forms of E. rhusiopathiae were cultivated in a 3H-thimidine-containing medium. A suspension washed three times in succession was intravenously injected into albino mice.

Histoautoradiographic studies on the fate of 3H-thymidine labelled L-forms of E. rhusiopathiae in albino mice.

L-forms of Erysipelotrix rhusiopathiae labelled with 3H-thymidine were intravenously administered to albino mice. Autoradiographic studies of the liver, kidney and spleen were undertaken at periods ranging from 2 minutes to 15 days. On the second minute following the administration of the radioactive material whole labelled microorganisms and chains of silver grains were recovered in the examined organs.