The blood-testis barrier (BTB) is a unique ultrastructure in the testis which creates a specialized microenvironment in the seminiferous epithelium for post-meiotic germ cell development and to maintain an immunological barrier. In this report, we have demonstrated unequivocally that a functional and intact BTB is crucial for initiation of spermatogenesis in particular differentiation of spermatogonial stem cells (SSCs). It was shown that adult rats (~300 gm body weight, b.w.) treated with adjudin at 50 (low-dose) or 250 (high-dose) mg/kg b.w. by gavage led to germ cell depletion from the seminiferous tubules and >98% of the tubules were devoid of germ cells by ~2-week and rats became infertile in both groups after the sperm reserve in the epididymis was exhausted. While the population of SSC/spermatogonia in the seminiferous tubules from both groups was similar to normal rats, only rats from the low-dose group were capable of re-initiating spermatogenesis by 20-week and by 30-week, greater than 75% of the tubules displayed normal spermatogenesis and the fertility of these rats rebounded. Detailed analysis by dual-labeled immunofluorescence analysis and a functional BTB integrity assay revealed that in both treatment groups, the BTB was disrupted from 6- to 12-week. However, the disrupted BTB “resealed” in the low, but not in the high, dose group. Our findings illustrate that that SSC/spermatogonia failed to differentiate into spermatocytes beyond Aaligned spermatogonia in the high-dose group with a disrupted BTB. In short, these findings illustrate the critical significance of BTB for re-initiation of spermatogenesis besides SSC and spermatogonia.

Formin 1 confers actin nucleation by generating long stretches of actin microfilaments to support cell movement, cell shape, and intracellular protein trafficking. Formin 1 is likely involved in microtubule (MT) dynamics due to the presence of a MT binding domain near its N terminus. Here, formin 1 was shown to structurally interact with α-tubulin, the building block of MT, and also end-binding protein 1 (a MT plus [+]-end-binding protein that stabilizes MT) in the testis. Knockdown of formin 1 in Sertoli cells with an established tight junction barrier was found to induce down-regulation of detyrosinated MT (a stabilized form of MT), and disorganization of MTs, in which MTs were retracted from the cell cortical zone, mediated through a loss of MT polymerization and down-regulation of Akt1/2 signaling kinase. An efficient knockdown of formin 1 in the testis reduced the number of track-like structures conferred by MTs and F-actin considerably, causing defects in spermatid and phagosome transport across the seminiferous epithelium. In summary, formin1 maintains MT and F-actin track-like structures to support spermatid and phagosome transport across the seminiferous epithelium during spermatogenesis.

We show that there are propagating modes for electromagnetic waves in a periodic array of superconductor and insulator with two-dimensional symmetry. For waves polarized perpendicular to the array, the vector Maxwell equations reduce to a scalar wave equation for the nonvanishing component of electric field. This reduction is still valid if the superconducting component has an anisotropic dielectric tensor, as in the high-T, CuO-based materials. Using the Mattis-Bardeen form for the finite-frequency conductivity of a superconductor below its gap, the wave equation becomes formally identical to a Schrodinger equation. We give numerical examples for the case of a two-dimensional array of air cylinders embedded in a superconducting host. The results suggest that these modes may be observable in a highly anisotropic high-T, superconductor with c axis parallel to the direction of wave polarization.It has been known for several years that periodic dielectric arrays may have photonic band gapsthat is, frequency regimes where electromagnetic waves may not propagateeven if the dielectric functions of both constituents are real and positive. ' These materials are called photonic band-gap materials. Such band gaps may have many applications. For example, they may be useful as new types of electromagnetic filters in difficult-to-

Age, tumour stage, and preoperative serum albumin level were predictors of survival after radical cystectomy. Non-cancer-related death played a crucial role in the overall mortality rate in elderly patients having radical cystectomy for bladder cancer.

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