Gross, histological and ultrastructural morphology of the aglomerular kidney in the lined seahorse Hippocampus erectus

Histologic evaluation of the renal system in the lined seahorse Hippocampus erectus reveals a cranial kidney with low to moderate cellularity, composed of a central dorsal aorta, endothelial lined capillary sinusoids, haematopoietic tissue, fine fibrovascular stroma, ganglia and no nephrons. In comparison, the caudal kidney is moderately to highly cellular with numerous highly convoluted epithelial lined tubules separated by interlacing haematopoietic tissue, no glomeruli, fine fibrovascular stroma, numerous capillary sinusoids, corpuscles of Stannius and clusters of endocrine cells adjacent to large calibre vessels. Ultrastructural evaluation of the renal tubules reveals minimal variability of the tubule epithelium throughout the length of the nephron and the majority of tubules are characterized by epithelial cells with few apical microvilli, elaborate basal membrane infolding, rare electron dense granules and abundant supporting collagenous matrix.

FUNGAL SYMBIONTS. Global assessment of arbuscular mycorrhizal fungus diversity reveals very low endemism

The global biogeography of microorganisms remains largely unknown, in contrast to the well-studied diversity patterns of macroorganisms. We used arbuscular mycorrhizal (AM) fungus DNA from 1014 plant-root samples collected worldwide to determine the global distribution of these plant symbionts. We found that AM fungal communities reflected local environmental conditions and the spatial distance between sites. However, despite AM fungi apparently possessing limited dispersal ability, we found 93% of taxa on multiple continents and 34% on all six continents surveyed. This contrasts with the high spatial turnover of other fungal taxa and with the endemism displayed by plants at the global scale. We suggest that the biogeography of AM fungi is driven by unexpectedly efficient dispersal, probably via both abiotic and biotic vectors, including humans.

Oral immunostimulation of the oyster Ostrea edulis: Impacts on the parasite Bonamia ostreae

Bioactive compounds were orally administered to the native European oyster Ostrea edulis to evaluate the immune response and the progression of infection of the protozoan parasite Bonamia ostreae. The immunostimulants lipopolysaccharide and zymosan directly administrated to the water column induced an increase in lysozyme activity and the percentage of granulocytes in naïve oysters over a period of 7 days. In another set of experiments, zymosan and curdlan were microencapsulated in alginate and also administered to the water column to naïve and B. ostreae infected O. edulis. Oyster mortality, prevalence and intensity of infection and several immune parameters were evaluated up to 28 days post-administration. Lysozyme activity, nitric oxide production and the expression of galectin, lysozyme and superoxide dismutase increased after 24 h in both infected and uninfected oysters. Zymosan immunostimulated oysters displayed a decrease in the prevalence of B. ostreae infection not attributed to mortalities but which could be associated to the enhanced ability of immunostimulants to evoke an enhanced immune response in the oysters and reduce infection.

Prognostic factors for recurrence after conservative treatment in a series of 119 patients with stage I serous borderline tumors of the ovary

BACKGROUND

The aim of this study was to evaluate prognostic factors for recurrence after conservative treatment of a large series of 'apparent' stage I serous borderline ovarian tumors (SBOTs).

PATIENTS AND METHODS

A review of 119 patients treated conservatively between 2000 and 2009 with follow-up data. All pathological slides were reviewed by the same expert pathologist. Prognostic factors for recurrence were studied (age, histological subtypes and surgical procedure).

RESULTS

Conservative surgical procedures were: unilateral cystectomy (n = 43, 36%); unilateral adnexectomy (UA; n = 50, 42%); bilateral cystectomies (n = 11, 9%) and UA + contralateral cystectomy (n = 15, 13%). Stromal microinvasion and/or a micropapillary pattern was present in 21 (18%) and 13 (11%) patients, respectively. With a median follow-up of 45 months, 38 (32%) patients relapsed (10 also had peritoneal disease in the form of noninvasive implants at the first recurrence). In 2 of these 38 patients, progression-to-invasive disease occurred at the second and third relapse (one patient died to the recurrence). Three prognostic factors for recurrence were identified in the univariate analysis: a young age (< or >30 years old), the type of conservative treatment (adnexectomy versus cystectomy) and tumor bilaterality. In the multivariate analysis, only age remained statistically significant.

CONCLUSION

In this series (the largest reported, to date, on recurrences after the conservative management of stage I SBOT), the risk of relapse was not related to tumor histological subtypes (micropapillary and stromal microinvasion) nor to the use of complete staging surgery. Invasive recurrences were very rare in stage I SBOT, but did occur. A young age, tumor bilaterality and the use of a cystectomy were identified as risk factors for recurrence, suggesting that management of fertility preservation (particularly in very young patients) should be associated with a meticulously conducted follow-up.