Amifostine protective effect on cisplatin-treated rat testis

Cisplatin is a potent drug used in clinical oncology but causes spermatogenesis damage. Amifostine is a drug used against toxicity caused by ionizing irradiation and chemotherapeutic drugs. Since cisplatin provokes fertility and induces germ cell apoptosis and necrosis, we proposed to evaluate the amifostine cytoprotective action on testes of cisplatin-treated rats. Thirty-day-old prepubertal Wistar rats received a single cisplatin dose of 5 mg/kg and were killed after 3, 6, and 12 hr. The hematoxylin-eosin stained testicular sections were submitted to histological, morphometric, and stereological analysis. The terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick end-labeling (TUNEL) method was used to label apoptotic cells. TUNEL-positive and TUNEL-negative germ cells with abnormal nuclear morphology (ANM) were scored. Significant alterations of greater part of the parameters occurred in the cisplatin-treated group (CE) compared to the group that received amifostine before the cisplatin-treatment (ACE); however, testicular weight and volume did not vary between these groups. Tubular diameter was reduced in CE in comparison to ACE rats, while interstitial tissue and lymphatic space volume and volume density were significantly higher in CE rats; interstitial testicular edema probably occurred in cisplatin-treated rats. CE rats showed important histological alterations, which were more accentuated than in ACE rats. The numerical densities of apoptotic germ cells and TUNEL-negative cells with ANM were lower in ACE than in CE rats. In conclusion, the amifostine previously administered to prepubertal rats reduced the testicular damage caused by cisplatin. We conclude that amifostine partially protected the rat seminiferous epithelium against cisplatin toxicity.

Effect of α-tocopherol, taurine and selenium on the attenuation of ischemia/reperfusion injury of splanchnic organs

Background: Splanchnic artery occlusion shock is caused by increased capillary permeability and cellular injury precipitated by oxygen derived free radicals following ischemia and reperfusion of splanchnic organs. The purpose of this study was to assess the role of several well-known oxygen- derived free radical scavengers in ameliorating or preventing this syndrome. Study design: Anesthetized rats were subjected to periods of occlusion of the visceral arteries and reperfusion. Tocopherol, taurine, selenium or a 'cocktail' of these three agents was injected subcutaneously for 4 consecutive days prior to operation. Mean arterial blood pressure was measured throughout the experimental period. Fluorometry and technetium-99m pyrophosphate counting of the visceral organs were performed as well as a histologic grading system for intestinal viability. Results: Final mean arterial blood pressure associated with the 'cocktail' and selenium groups was 79.1 ± 27.4 mmHg and 83.6 ± 17.8 mmHg, respectively. These values were significantly higher than the control group, 40.8 ± 11.4 mmHg (P < 0.05). Similar patterns of the benefit of selenium in contrast with the other groups were obtained with fluorescein perfusion, radioisotopic activity and histologic analysis. Conclusion: Pretreatment with selenium of splanchnic ischemia and reperfusion in the rat improves mean arterial blood pressure and microcirculatory visceral perfusion. Further analysis of the precise protective mechanism of selenium for reperfusion injury will enable visceral organs to withstand the consequences of increased capillary leakage and oxidant injury.

A scanning electron microscopic study of the rete testis of the guinea pig

Scanning electron microscopic (SEM) observations of the structure of the rete testis (RT) of guinea pigs preceded by and complemented with stereomicroscopy and light-microscopic studies showed that the RT of this species is predominantly cavitary. An axial and labyrinth-like morphological pattern was also observed in the RT complex, with partially interconnected chambers and epithelium-lined channels accompanying a connective axis observed in the middle portion of the cranial end of the testis. Characteristics of the chordae retis and bullae retis were also visualized in the guinea pig RT and the results are discussed in terms of the morphological patterns observed in the RT of other mammals and of man.

Morphology of testis and epididymis in an ethanol-drinking rat strain (UChA and UChB)

The objective of the present study was to analyze the prospective alterations of the testis and epididymis in a defined strain of alcoholic rats in order to contribute to our understanding of the effects of chronic alcoholism on reproduction. The testis and epididymis of the animals were submitted to morphological analysis by macroscopy, light microscopy and electron microscopy and to morphometric analysis. The UCh rats showed atrophy of the epithelium and reduction of testis and epididymis weight, liver hypertrophy and fat infiltration and alterations of the hypothalamus-pituitary axis. Ethanol induces changes in the weight and in the epithelium of the testis and epididymis and in the hypothalamus-pituitary axis of the UCh rats.

Laparoscopic evaluation and treatment of the impalpable testis

Objectives: To evaluate the laparoscopic technique as a diagnostic and therapeutic tool in the management of patients with impalpable testis. Material and Methods: Fifty-nine patients with mean age of 6.3 years underwent laparoscopy to evaluate 85 impalpable testes that were classified as absent, canalicular and intra-abdominal. In the case of testicular absence, the procedure was terminated. In the case of canalicular testis, open inguinal exploration was performed. In intra-abdominal testis, either laparoscopic orchiopexy or orchiectomy was performed. According to the length of the vascular pedicle, orchipexy was performed either with or without vascular ligature. Post-operatively, the treated testes were evaluated according to size and location in the scrotum. Results: Seventeen (20%) of the 85 impalpable testes were diagnosed as absent, 21 (24.7%) as canalicular and 47 (55.3%) as intra-abdominal. Of the canalicular testes, 20 were explored by inguinotomy and one by laparoscopy. All the intra-abdominal testes were treated initially by laparoscopy, four being removed due to atrophy, 31 submitted to vascular ligature and 12 to primary orchipexy. Of those submitted to vascular ligature, 22 underwent a second stage orchipexy, of which 18 laparoscopically and 4 by inguinotomy. Of the 18 testes brought to the scrotum by staged laparoscopic orchipexy, 15 (83.3%) presented normal characteristics in the late follow-up, while of the 12 submitted to primary laparoscopic orchipexy, 8 (66.6%) were normal. There were no perioperative or late complications. Conclusions: Laparoscopy is a minimally invasive procedure with low morbidity that enables precise diagnosis of the impalpable testes. When intra-abdominal testes are found, either immediate laparoscopic orchiectomy, or primary and staged orchipexy are possible, with results equivalent to open procedures, with the advantage of smaller surgical incisions and shorter postoperative recovery.

Cytogenetical and histological studies in testis of Tayassu tajacu (Cateto), Tayassu pecari (Queixada) and a natural interspecific hybrid

The karyotype, the histological structure of the testis and the synaptonemal complex (SC) of the mammalian species Tayassu tajacu, Tayassu pecari and of an interspecific male hybrid captured in nature were analysed. The specimens of T. tajacu (2n = 30) and T. pecan (2n = 26) exhibited seminiferous tubules with germ cells in all sperma to genesis stages. In the SC studies both species had a regular structure, easily identified in the autosomes and in the sex chromosomes. The hybrid (2n = 28) had seminiferous tubules with almost all germinal cells in the spermatogonium stage and only a few cells in the primary spermatocyte stage. Gross abnormalities in SC were observed. A few lateral elements showed regular or partially regular synapsis, other lateral elements were synapsed as multivalents, and most axial elements remained unsynapsed. The results suggest that the karyotypes of the parental species have sufficient differentiation to avoid chromosome synapsis. Alternatively, the hypothesis of the existence of genetic incompatibilities between the parental species is discussed.

Effects of contrast material on computed tomographic measurements of lung volumes in patients with acute lung injury

Background. Intravenous injection of contrast material is routinely performed in order to differentiate nonaerated lung parenchyma from pleural effusion in critically ill patients undergoing thoracic computed tomography (CT). The aim of the present study was to evaluate the effects of contrast material on CT measurement of lung volumes in 14 patients with acute lung injury. Method. A spiral thoracic CT scan, consisting of contiguous axial sections of 10 mm thickness, was performed from the apex to the diaphragm at end-expiration both before and 30 s (group 1; n=7) or 15 min (group 2; n=7) after injection of 80 ml contrast material. Volumes of gas and tissue, and volumic distribution of CT attenuations were measured before and after injection using specially designed software (Lungview®; Institut National des Télécommunications, Evry, France). The maximal artifactual increase in lung tissue resulting from a hypothetical leakage within the lung of the 80 ml contrast material was calculated. Results. Injection of contrast material significantly increased the apparent volume of lung tissue by 83 ± 57 ml in group 1 and 102 ± 80 ml in group 2, whereas the corresponding maximal artifactual increases in lung tissue were 42 ± 52 ml and 31 ± 18 ml. Conclusion. Because systematic injection of contrast material increases the amount of extravascular lung water in patients with acute lung injury, it seems prudent to avoid this procedure in critically ill patients undergoing a thoracic CT scan and to reserve its use for specific indications.

The ultrastructure of the guinea pig rete testis

The chambers of the rete testis (RT) of guinea pig are lined by a simple epithelium, whose cells are squamous, cubical and columnar in shape. The epithelial cells with distinct shapes were counted and the quantitative analysis of the number of these cells showed relative predominance of cubical cells. The ultrastructural observations showed predominance of membrane interdigitations among the epithelial cells. These cells present common cytoplasmic organelles. The Golgi complex polarity is typical with observation of electronlucent vesicles on the Golgi cis face closely related to rough endoplasmic reticulum (ER) lamellae, mitochondria and large number of polysomes on the Golgi trans face. These related structures present in Golgi area of RT cells suggest secretory activity which maybe occurs in the RT epithelium. Endocytotic process also occurs in the RT and this function probably concerns the uptake of substances and resorption of seminiferous fluid. Apical cilia present in RT epithelium cells are related with fluid transport and perhaps with chemoreception. Presence of spermatozoa portions enclosed into the cytoplasm of some epithelium cells has been refferred to as spermatophagy. The RT complex is mainly supported by loose connective tissue, with collagen fibres and some Leydig cells. Leydig cells are adjacent to the network channels of the septal part of the RT and apparently are able to secrete inside the RT lumen.

Immune regulatory effect of pHSP65 DNA therapy in pulmonary tuberculosis: Activation of CD8+ cells, interferon-γ recovery and reduction of lung injury

A DNA vaccine based on the heat-shock protein 65 Mycobacterium leprae gene (pHSP65) presented a prophylactic and therapeutic effect in an experimental model of tuberculosis. In this paper, we addressed the question of which protective mechanisms are activated in Mycobacterium tuberculosis-infected mice after immune therapy with pHSP65. We evaluated activation of the cellular immune response in the lungs of infected mice 30 days after infection (initiation of immune therapy) and in those of uninfected mice. After 70 days (end of immune therapy), the immune responses of infected untreated mice, infected pHSP65-treated mice and infected pCDNA3-treated mice were also evaluated. Our results show that the most significant effect of pHSP65 was the stimulation of CD8+ lung cell activation, interferon-γ recovery and reduction of lung injury. There was also partial restoration of the production of tumour necrosis factor-α. Treatment with pcDNA3 vector also induced an immune stimulatory effect. However, only infected pHSP65-treated mice were able to produce significant levels of interferon-γ and to restrict the growth of bacilli.

Cysts reabsorption in the testis of the bee wax pest Achroia grisella (Lepidoptera, Pyralidae) during spermatogenesis

The present paper reports the occurrence of testicular cysts degeneration during spermatogenesis of Achroia grisella, a Lepidoptera with dimorphic spermatogenesis, through ultrastrucutural studies. Signs of cysts degeneration can be detected in the last larval instar but it increases during pupation and early adulthood. The degeneration affects the eupyrene, as well apyrene cysts but it is not always possible to recognize which cysts are degenerating. Some morphological features of cysts degeneration resemble apoptosis.